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Authorship：Last author   Language：Japanese   Publishing type：Research paper (scientific journal)  

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society for Analytical Chemistry  

Potentiometric ammonia gas sensors based on a YSZ solid electrolyte were fabricated. The Pt electrode on the detection side was coated with hexagonal boron nitride (h-BN) powder. Milling treatment of the h-BN powder in ethanol significantly enhanced the EMF response to 30 ppm ammonia gas. The sensor linearly responded to a logarithm of the ammonia concentration, suggesting a mixed-potential mechanism based on a competitive reaction of oxidation of ammonia and reduction of oxygen. The EMF response depended on the milling time
milling for 48 h gave the maximum response. The response enhancement was explained as that the exfoliation of h-BN and B-N bond cleavage induced ammonia adsorption onto the h-BN layer. On the contrary, a milling treatment in water reduced the response to ammonia. The formation of -OH/-NH2 on the h-BN may decrease of the ammonia adsorption. Humidification of ammonia reduced the sensor response to 80% of the response in dry ammonia. Loading Ag on the h-BN powder further enhanced the sensor response, due to that ammonia preferentially adsorbed on Ag particles on a h-BN support.

DOI： 10.2116/bunsekikagaku.68.937

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：ELSEVIER  

The spinel type MgFe2O4 ferrite powder having self-heating ability in an AC magnetic field was prepared by polymerization method in order to investigated the application for thermal coagulation treatment of cancer tissue. The single phase of cubic ferrite structure was obtained for all sample synthesized with different CA/MN (Citric Acid / Metal Nitrate) conditions. The heat-generation-ability was extremely improved at CA/MN=2.0 sample (Delta T = 168 degrees C), however the heat-generation-property decreased with increase in CA/MN ratio. Hysteresis loss value also increased at CA/MN=2.0 sample, it was suggested that the heat-generation-ability of MgFe2O4 powder prepared by polymerization method was depended on hysteresis loss value. (C) 2019 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.matpr.2019.05.287

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Electrochemical Society Inc.  

The growth of Ni grains in sintered 60wt%Ni-BCY anode supports for solid oxide fuel cells and their electrical conductivities were evaluated. The critical grain growth was confirmed in a Ni-BCY disk sintered at a temperature higher than 1450 °C, resulting in a large degree of decline in electrical conductivity. In addition, reducing the Ni content in Ni-BCY did not effectively suppress the Ni grain growth. Addition of GDC into the Ni-BCY (Ni-BCY-GDC) was found to effectively inhibit the Ni grain growth after sintering at 1450 °C, which remarkably enhanced the electrical conductivity compared with those of the Ni-BCY supports. Adding GDC into BCY simultaneously suppressed the grain growth of the BCY. The grain sizes of Ni are in a linear relationship with grain size over volume fraction (r/f) of the oxide phase, implying that the Ni grain growth was prevented by the pinning pressure from the oxide grains.

DOI： 10.1149/09101.1963ecst

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier B.V.  

The Cs ion was partially adsorbed (4.0% in all of the alkali cation sites) on natural mordenite as a simulated decontamination, then heat-treated to immobilize the Cs in the decomposed zeolite. Although the mordenite phase was maintained for the samples even heated at 800 °C, a glassy amorphous phase formed due to the decomposition of the mordenite at 900 °C. In the case of the non-treated sample, 3.6% Cs ion from all of the adsorbed Cs was eluted by a dissolution test in deionized water for 14 days. The elution ratio of the Cs ion decreased by the heat treatment. The Cs ion did not elute when the sample was heated at 1000 °C and higher temperature due to the Cs containment in the glassy phase. Na2CO3 powder was mixed with the mordenite for lowing the glass-forming temperature. The mordenite mixed with Na2CO3 had a lower melting point and immobilized the Cs at 900 °C. The Cs evaporation during the heating was also depressed by the Na2CO3 addition.

DOI： 10.1016/j.jnucmat.2018.05.027

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

In this paper, we report a detailed study of magnetic properties and AC magnetic heat generation characteristics of La0.77Sr0.23MnO3 (LSMO) nanoparticles to investigate appropriate crystallite size with a view to the proper application of self-controlled magnetic hyperthermia treatments of cancer. A series of nanocrystalline LSMO manganite was synthesized through the chemical route called as "polymerized complex method" and then subsequently annealed at the different temperature from 600 to 1400 degrees C to obtain various crystallite size. Phase formation and crystal structure of the prepared powder were determined by the powder X-ray diffraction (XRD) using Rietveld analysis. The XRD patterns reveal that all powder samples are a single phase rhombohedral perovskite-like structure with R (3) over barc space group. The mean crystallite size of prepared particles varied from 19 to 243.8 nm with the increase of the annealing temperature starting from 600 to 1400 degrees C. The field emission scanning electron microscopy (FE-SEM) analysis shows the surface morphology with a strong agglomeration of fine nanoparticles. The Magnetic study reveals that these nanoparticles exhibit ferromagnetic nature with different value of magnetization, coercivity, Curie temperature which is strongly dependent on their crystallite size. The maximum saturation temperature (Ts = 66 degrees C) under AC magnetic field (H = 1.77 kA/m, f = 370 kHz) was found for the crystallite size of 39.5 nm due to its pure single domain phase. Such LSMO nanoparticles, having the higher heating rate, can be used in magnetically induced hyperthermia cancer treatment.

DOI： 10.1016/j.jpcs.2017.09.030

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Electrochemical Society Inc.  

The membranes consisting of samaria-doped cerias, (SmO1.5)0.2(CeO2)0.8 (SDC), containing 10~50 wt% nickel were formed by electrophoretic deposition (EPD). The membranes were examined as SOFC anodes fueled with 6% ammonia. The catalytic activity of ammonia decomposition was higher in the lower Ni contents of 0~30 wt%. The anodic performances were similar between 10~40 wt%. The impedance analysis of the anodes suggested that increase in the Ni content increased the resistance of electrochemical oxidation, and deceased in the low frequency component, which might be assigned to a molecular diffusion process.

DOI： 10.1149/08513.0779ecst

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

The superparamagnetic magnesium ferrite (MgFe2O4) dense nanospheres are synthesized by ultrasonic spray pyrolysis (USP) method from different concentrations of the initial precursor solution. The effect of precursor solution concentration on the particle's size, morphology, and superparamagnetic behavior has been investigated. XRD results confirm that studied precursor concentration (0.06, 0.12 and 0.24 M) exhibited single phase cubic structure. The mean crystallites size (called as primary particles) of 0.06, 0.12 and 0.24 M samples are 9.6, 11.5, 11.0 nm, respectively but the entire nanosphere's diameter (called as secondary particles) increases from 206 to 340 nm with increasing precursor concentration. TEM analysis also reveals that nanospheres consist of densely aggregated crystallites of spherical shape and smooth surface. The value of polydispersity index (PDI) shows narrower size distribution for lower concentration. Magnetic properties indicate the superparamagnetic nature for all samples. Herein, the appropriate induction heat generation rate with better morphology was obtained for 0.06 M concentration. Ion release in the aqueous solution of the composition (about 95% for Mg; 99% for Fe) indicating better stability has been confirmed by ICP-OES test. In this approach, as-synthesized nanospheres are suitable for using as a heating agent in magnetic thermotherapy application. (C) 2017 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.

DOI： 10.1016/j.apt.2017.04.007

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Anode-supported solid oxide fuel cells with a thin layer of proton conducting BaCe0.8Y0.2O3- (BCY) were fabricated by electrophoretic deposition technique using an organic suspension. BCY green films were formed on a graphite-added NiO-BCY substrate. By the classification of particle size distribution by the suitable period of sedimentation yielded a crack-free green film. Sintering of the crack-free green film at 1450 degrees C yielded a dense layer of BCY with the thickness of about 9.2 +/- 0.3 mu m after sintering at 1450 degrees C. The BCY thin film on the NiO-BCY substrate exhibited conductivity of 1.6 x 10(12)S.cm(-1) at 600 degrees C and its activation energy was 0.35 eV. The anode-supported single cell with the BCY thin film resulted in the maximum power density of 74.2mW.cm(-2) at 600 degrees C. (C) 2017 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.17048

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Hydrogen permeation properties of Gd0.1Ce0.9Ox/BaCe0.80Y0.20O3-delta (GDC/BCY) dual-phase membranes were evaluated. Nongalvanic hydrogen permeation was observed for 46 vol% GDC-containing BCY membranes: the permeation rate was 0.30 ml.min(-1).cm(-2) at 800 degrees C. This is almost comparable to the reported value of Ni-BCY cermet (0.50 ml.min(-1).cm(-2)). This nongalvanic hydrogen permeation unambiguously indicates that the BCY-GDC composite functions as a mixed proton-electron conductor in an H-2 reducing atmosphere. From a conductivity analysis, it was deduced that 46 vol% GDC/BCY possesses proton and electron conductivities comparable to the bulk states of BCY and GDC. The composite membrane was stable in an atmosphere switching between H-2 and air. TGA analysis indicated that addition of GDC enhanced the stability of the BCY phase in CO2. (C) 2017 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.16230

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Language：English   Publishing type：Part of collection (book)   Publisher：Elsevier Inc.  

Pearl shells, which are yielded as a waste during jewel pearl culture process at Uwajima sea in Ehime prefecture, Japan, are micro-/nanostructured composite materials alternatively consisting of organic and inorganic CaCO3 layers with nanothicknesses. Micro-/nanosized pearl particles are candidates for Ca nutrients and hydroxyapatite (HAp) formation. Iron oxide nanocubes with surfactant are self-assembled into closed packing structures. The integrated structure of thermal-imprinted glass templates with functional nanoparticles becomes a potential candidate for new therapeutic nanostructures. Magnetic Y3Fe5O12 and Fe3O4 particles prepared by either break down or built-up processes were evaluated for thermal coagulation therapy. The dissolution behavior of micrometer-sized pearl powder was also evaluated in artificial stomach acid at 37°C. Future directions of micro-/nanostructured materials are proposed for biomedical applications.

DOI： 10.1016/B978-0-323-46142-9.00004-9

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Society of Powder Technology  

The decontamination of Cs in rice fields is necessary for the continuation of agriculture in the Fukushima prefecture. A composite material consisting of the Na-P1 type zeolite and magnetite was synthesized from the fly-ash and iron chlorides, because the magnetic collection was possible using this composite material after radioactive Cs+ ion adsorption. The existence of nano-sized magnetites in the polycrystalline zeolite (several micrometers) was confirmed by SEM and TEM observations. By mixing soil with the magnetized Na-P1, with the mass ratio of 10:1, in ammonium oxalate solution for 10 min, more than 80% of radioactive Cs was removed from soil. The composite powder material consisting of mordenite and nano-sized magnetite was also synthesized from a mixed slurry of the diatomite and nanosized magnetite.

DOI： 10.4164/sptj.54.524

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：日刊工業出版プロダクション ; 1955-  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TSINGHUA UNIV PRESS  

Composite powder material of the Y3Fe5O12-nSiC system was synthesized by a reverse coprecipitation method to study its heat generation property in an AC magnetic field. For Y3Fe5O12 (n = 0), the maximum heat generation ability of 0.45 W.g(-1) in an AC magnetic field (370 kHz, 1.77 kA.m(-1)) was obtained for the sample calcined at 1100 degrees C. The SiC addition helped to suppress the particle growth for Y3Fe5O12 at the calcination temperature. The heat generation ability was improved by the addition of the SiC powder, and the maximum value of 0.93 W.g(-1) was obtained for the n = 0.3 sample calcined at 1250 degrees C. The heat generation ability and the hysteresis loss value were proportional to the cube of the magnetic field (H-3). The heat generation ability (W.g(-1)) of the Y3Fe5O12-0.3SiC sample calcined at 1250 degrees C could be expressed by the equation 4.5x10(-4).f.H-3 using the frequency f(kHz) and the magnetic field H(kA.m(-1)).

DOI： 10.1007/s40145-016-0198-9

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Mordenite was synthesized using chemical reagents of amorphous SiO2 and sodium aluminate without the addition of a template agent and a seed powder. The single phase of the mordenite was obtained for the Al/Si ratios of 0.085-0.120 as the starting material in the reaction temperature range of 170-200 degrees C for 24 h. The cation exchange capacity (CEC) was ca. 180-210 cmol/kg and it increased with the Al/Si ratio. The Cs+ adsorption ability from 100ppm Cs+ 100mL solutions of water and seawater for the mordenite (1.0 g) was > 99% and ca. 85-92%, respectively. A composite material consisting of the mordenite and magnetite (10, 20, 30 wt%) was synthesized for the magnetic collection. The total Cs decontamination rates using the magnetic collection material after the Cs+ adsorption in water were also higher than 95% for all the examined magnetite-containing composite materials. (C) 2016 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.15317

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© 2006-2016 Asian Research Publishing Network (ARPN). A white rice husk ash with a silica content of more than 99% was produced from a rice husk by a citric acid treatment before heating the rice husk at 700 °C to 1000 °C. The white ash mostly consisted of an amorphous phase, and cristobalite usually found after heating rice husk was not detected. The amorphous phase was still formed although the rice husk was burned at 1000 °C. These indicated that the citric acid dissolved part of the carbon compounds in the rice husk, followed by releasing of potassium and other alkali cations, and as a result, an amorphous high silica ash was formed without incorporation of crystal phases such as cristobalite. The white rice husk ash was successfully converted into ZSM-5, a zeolite widely used as a catalyst in the petroleum industries.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

The synthesis conditions of a nano-sized magnetite powder using a reverse coprecipitation method were studied in order to control the particle size and the heat generation ability in an AC magnetic field for thermal coagulation therapy. A low temperature reaction and high concentration of the mixed irons as the starting materials in solution increased the particle size of the magnetite powder. The particle size decreased with an increase in the concentration of the coexisting Na+ and Cl- ions. The particle size was enhanced with an increase in the R = Fe2+/(Fe2+ + Fe3+) molar ratio of the divalent iron, and the maximum heat generation ability was obtained at the R = 0.33 molar ratio. The maximum heat generation ability of 0.25-0.28 W.g(-1) in the AC magnetic field (370 kHz, 1.77 kA.m(-1)) was obtained for the magnetite having an ca. 13-14 nm particle size. (C) 2016 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.15183

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Partially Ag-exchanged Na-P1 type zeolites were prepared using an Na-P1 type zeolite and a silver nitrate solution. Emission spectra of the samples prepared at various concentrations of the silver nitrate solution and at various subsequent heat-treatment temperatures were compared. The structure of the Na-P1 type zeolites was changed to an amorphous phase by the heat-treatment at 400 degrees C or higher. When the amorphous materials were irradiated with 254 nm ultraviolet light, these samples showed a high intensity violet luminescence with an emission peak around 390 nm. (C)2016 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.15140

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

A luminescent material free of rare earth elements was prepared from a partially Ag+ exchanged zeolite X. One gram of a commercially available zeolite X (Na+ form) was mixed with 100 mL of AgNO3 aqueous solutions of 2.0 to 50 mmol/L. The mixtures were shaken for 24 h, then the solid products were separated and dried at 50 degrees C. Some of the products were heated at 100 to 800 degrees C in atmospheric air. Luminescence was observed from the products with Ag loadings of 0.5 mmol/g or higher. These products showed yellow luminescence under UV light excitations of 254 and 312 nm. The luminescent products showed two excitation bands with peak maxima at 271 and 311 nm, and a single emission band at 550 nm. The luminescence intensity was low for the 0.5 mmol/g Ag loaded sample, but it significantly increased with the increasing amounts of Ag+ up to a 1.0 mmol/g loading, then a quenching occurred with a further increased Ag+ loading. Heating of the Ag-loaded zeolite X decreased the luminescence intensity. Heating the Ag loaded zeolite X at 800 degrees C resulted in a low blue luminescence intensity due to collapsing the zeolite X structure into an amorphous phase. This study suggested that a luminescent material free of rare earth elements can be fabricated from Ag-exchanged zeolite X without any heat treatment. The highest luminescence intensity was attained at the Ag loading of 1.0 mmol/g, along with a measured internal quantum efficiency of 20.8% (lambda ex. = 311 nm). (C) 2016 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.15199

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：AMER INST PHYSICS  

Al substituted MgAlXFe2-XO4 that have high heat generation ability in the AC magnetic field was obtained by Sol-Gel method. The heat generation ability was improved by Al3+ substitution, the highest heat generation property (Delta T = 127.2 degrees C) was confirmed for X=0.25 sample. This high heat generation ability was depended on hysteresis loss value, the hysteresis loss for X=0.25 samples were significantly increased in the AC magnetic field.

DOI： 10.1063/1.4961342

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

The radioactive decontamination of water, soil and other materials requires cheap and effective adsorbents. Artificial zeolites synthesized from an industrial waste (coal fly ash: Na-P1 type zeolite) and a natural material ( diatomite: mordenite type zeolite) have a high Cs+ adsorptivity in the adsorption experiments using 0.1 g of the zeolite and 50 mL of up to 7.5 mM CsCl. The coexisting cation suppressed the Cs+ adsorption onto the zeolites, and the effect of the suppression was in the order, K+ > Na+ > Ca2+ > Mg2+. A thermodynamic analysis proved that the Cs+ adsorption onto the two zeolites was exothermic favoring a lower temperature. The artificial mordenite showed a greater Cs+ adsorption strength, higher distribution coefficient and lower Delta G degrees, especially at low Cs+ concentrations. Adsorption isotherm analysis by the Langmuir, Freundlich, Temkin and Dubinin-Radushkevich models showed a greater Cs+ adsorption selectivity for the artificial mordenite even at a low pH. (C) 2015 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.123.1065

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

In this paper, we present the synthesized of magnesium ferrite (MgFe2O4) nano -spheres by a single-step ultrasonic spray pyrolysis (USP) technique from the aqueous metal nitrate precursor solution without any organic additives or post annealing processes. The effects of different pyrolysis temperatures on the particles size, morphology and their superparamagnetic behavior have been investigated to evaluate the heat generation efficiency in an AC magnetic field. The X-ray powder diffraction spectra of MgFe2O4 nano-spheres synthesized at the pyrolysis temperatures of 600, 700, 800 and 900 degrees C exhibited single phase cubic structure and obtained mean crystallite size (primary particles) of 4.05, 9.6, 15.97 and 31.48 nm, respectively. Transmission electron microscopy (TEM) confirms that the particles consisted of aggregates of the primary crystallite had densely congested spherical morphology with extremely smooth surface appearance. Field emission electron microscopy (FESEM) reveals that the shape and size of the nano-spheres (secondary particles) does not change significantly but the degree of agglomeration between the secondary particles was reduced with increasing the pyrolysis temperature. The average size and size distribution of nano-spheres measured using electrophoretic scattering photometer have found very low polydispersity index (PK for all samples. The field dependent magnetization studies indicated superparamagnetic nature for the particles having crystallite size i.e. 4.05 and 9.6 nm and exhibited ferromagnetic nature for 15.97 and 3148 nm. It is also demonstrated that, as the pyrolysis temperature increases, the saturation magnetization of the MgFe2O4 nanopowders increases due to enhancement of crystallites. The shift in Curie temperature is well described by the finite-size scaling formula. The magnetically loss heating values of selected samples in crystallite size of 9.6 and 15.97 nm were investigated by measuring the time dependent temperature curves in an external alternating magnetic field (370 kHz, 1.77 kA/m). The more heat generation ability was obtained for 9.6 nm in crystal size because of minimum squareness ratio with coercivity in superparamagnetic range. The results reported in this study are useful to find out of superparamagnetic limit for the preparation of MgFe2O4 nanopowders. (C) 2015 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jmmm.2015.05.029

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

Y3Fe5O12 ferrite powder with addition of La having high heat generation ability in an AC magnetic field was prepared by reverse coprecipitation method. The highest heat generation temperature was obtained for the La 0.3 mol added sample calcined at 1150 degrees C.

DOI： 10.1246/cl.150480

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Sm2O3/SmFeO3 mixed powders were applied to a chemo-resistive VOC (volatile organic compound) gas sensor. The sensor response to 30 ppm toluene gas increased with increasing the Sm2O3 content up to 30 wt%, but decreased by further adding. The addition of Sm2O3 up to 30 wt% also enhanced the catalytic activity for toluene oxidation, as the result of the sensor response. The amount of toluene adsorption increased with increase in the surface Sm concentration. It was concluded that adding Sm2O3 increased the amount of adsorbed VOCs, resulting in the enhancement of the sensor response and the catalytic activity. Furthermore, adding Sm2O3 remarkably shortened the recovery time from the VOCs to air. For the ethanol sensing, adding Sm2O3 was only effective on shortening the recovery time. (C) 2015 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.123.961

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

Ferrimagnetic Y3Fe5O12 powder was synthesized by a reverse coprecipitation method in order to study its heat generation property in an AC magnetic field. An orthorhombic YFeO3 phase having a small particle size (<100 nm) was obtained for the samples calcined at a low temperature. The maximum heat generation ability in an AC magnetic field was obtained for the Y3Fe5O12 ferrite powder by calcination at 1100 degrees C. The heat generation ability was reduced for the samples calcined at a higher temperature. The particle growth with the formation of the cubic single phase might influence the heat generation ability. The heat generation ability and the hysteresis loss value were proportional to the cube of the magnetic field (H-3), because the coercivity value of the B-H curve was proportional to the square of the amplitude of the AC magnetic field (H-2). The heat generation ability (W g(-1)) of the Y3Fe5O12 sample sintered at 1100 degrees C can be expressed by the equation 2.2 x 10(-4).f.H-3 using the frequency (f/kHz) and the magnetic field (H/kA m(-1)), which has the highest heat generation ability of the reported magnetic materials. The hysteresis loss value for the B-H curve agreed with the heat generation ability of the samples calcined at 1100 degrees C and lower temperatures. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

DOI： 10.1016/j.ceramint.2015.03.048

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Mordenite was artificially synthesized using various diatomites for radioactive Cs decontamination. A high CEC (Cation Exchange Capacity) value was obtained when the diatomite had a high Al/Si elemental ratio. The Cs+ adsorption rate from 100 ppm Cs solution for the synthesized mordenite (1.0 g) was ca. 100% and ca. 83% in 100 mL of water and seawater, respectively. The composite powder material consisting of mordenite and nano-sized magnetite was synthesized from a mixed slurry of the diatomite and nano-sized magnetite. Magnetic collection rate for the composite material using a neodymium magnet was larger than 90% for the 20 and 30 wt% magnetite-containing composite materials. The total Cs decontamination rates using magnetic collection after the Cs+ adsorption in water were 92.7% and 97.2% for the 20 and 30 wt% magnetite-containing composite material, respectively. (C) 2015 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.123.129

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：ELSEVIER SCIENCE BV  

Adsorption experiments of Cs+ were carried out by using two natural zeolites, namely mordenite and clinoptilolite. The same experiments were also conducted by using synthetic zeolite A, synthetic zeolite X, and artificial zeolite Na-P1 as references. The purpose of this study was to investigate the potential of natural zeolites on the adsorption of radioactive Cs+. The results indicated that although cation exchange capacity of the natural zeolites was much lower compared to the synthetic and artificial zeolites, the adsorption capacity of Cs+ was much greater than the synthetic and artificial zeolites. The order of the adsorption capacity of Cs+ was mordenite&gt;clinoptilolite&gt; Na-P1 &gt;&gt; zeolite A &gt; zeolite X. It indicates that natural zeolites are promising materials in the removal of radioactive Cs+. 2015 The Authors. Published by Elsevier B.V.

DOI： 10.1016/j.proenv.2015.07.008

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Thermal coagulation therapy using powdered magnetic materials in an alternating (AC) magnetic field has been expected as a treatment of cancerous tissues. For nano-sized superparamagnetic particles, the magnetic energy is mainly converted to a heat generation ability by the rotation of the magnetic moment (Neel relaxation) along with the rotation of the particles (Brownian relaxation). Fe3O4 (magnetite) nanoparticles have been mainly investigated as the candidate material for this type of therapy. In this review, an outline of the ferrite materials having heat generation ability in the AC magnetic field is described for the application of the thermal coagulation therapy. In particular, I focused on the preparation of a nano-sized magnetic material using physical bead milling to develop a magnetic material of Y3Fe5O12 and its high heat generation ability. The preparation of Y3Fe5O12 microspheres with a 20-32 mu m diameter range using the bead-milled powder was also described for the embolization method of cancer treatment. (C) 2014 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.122.237

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Nano-sized Y3Fe5O12-nSmFeO(3) mixed powder (ca. 20 nm in particle size) was prepared by bead-milling using 0.05 mm phi beads for 10 h. For the SmFeO3-free sample (n = 0), the heat generation ability in an AC magnetic field (370 kHz, 1.77 kA.m(-1)) was 0.34 W.g(-1) for the bead-milled sample, and it was increased by a calcination at low temperature. The maximum ability of 0.46 W.g(-1) in an AC magnetic field (370 kHz, 1.77 kA.m(-1)) was obtained for the Y3Fe5O12 (n = 0) sample (36.8 nm in particle size) calcined at 700 degrees C. The heat generation mechanism changed from superparamagnetic to ferrimagnetic due to particle growth at 700 degrees C for the n = 0 sample, because the heat generation ability (W.g(-1)) depended on the cube of the magnetic field. A mixed SmFeO3 phase acted as an impurity for depression of the particle growth for the Y3Fe5O12 particles. The heat generation ability was slightly improved by the addition of SmFeO3 and the maximum value was 0.48 W.g(-1) in an AC magnetic field (370 kHz, 1.77 kA.m(-1)) for n = 0.2 and 0.4 samples. The maximum heat generation ability was decreased for the excessive SmFeO3 mixed sample (n = 0.6). The calcination temperature for the formation of the ferrimagnetic material was increased by the SmFeO3 addition due to the depression of particle growth. (C)2014 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.122.35

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DOI： 10.2109/jcersj2.122.P1-1

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：IOS PRESS  

Nano-sized superparamagnetic Y3Fe5O12 ferrite having a high heat generation ability in an AC magnetic field was prepared by physical bead milling. The highest heat ability in the AC magnetic field was for the fine Y3Fe5O12 powder with a 16-nm crystallite size (the samples were milled for 4 h using 0.1 mm phi beads). The main reason for the high heat generation property of the milled samples was ascribed to an increase in the Neel relaxation of the superparamagnetic material. For the samples milled for 4 h using 0.1 mmf beads, the heat generation ability (W.g(-1)) was estimated using a 3.58 x 10(-4).f.H-2 frequency (f/kHz) and the magnetic field (H/kA.m(-1)), which is the highest reported value of superparamagnetic materials. Furthermore, Y3Fe5O12 microspheres having a 20-32 mu m diameter range were prepared by a spray dryer using the bead-milled nano-sized particles.

DOI： 10.3233/JAE-141763

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Language：Japanese   Publishing type：Research paper (other academic)  

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Y3Fe5O12 microspheres having a 20-32 μm diameter range were prepared by a spray dryer using a bead-milled nanosize powder. The high heat generation ability in an AC magnetic field was obtained by the bead milling of a commercial powder. The yield of the 20-32 μm microspheres was 13.5% after sifting using 20 and 32 μm sieves. The heat generation ability of the microsphere sample was almost the same as that for the bead-milled powder because the temperature enhancement mechanism was the Néel relaxation of the superparamagnetic material. Furthermore, the heat generation ability of the Y3Fe5O12 microsphere was improved by calcination at low temperature. The heat ability increased as a function proportional to the square of the increasing magnetic field for the noncalcined sample and the samples calcined at 600°C. For the samples calcined at 650°C or higher, the heat generation ability increased as a function proportional to the cube of the increasing magnetic field because of the particle growth to form single-domain ferrimagnetic particles. The sample calcined at 650°C showed the maximum heat generation ability(W/g) of 2.4·f·H3, where f and H are the frequency (kHz) and magnetic field (kA/m), respectively. © 2013 The American Ceramic Society.

DOI： 10.1111/jace.12511

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

The Na-P1-type zeolite having a high cation-exchange capacity (CEC) was obtained using the waste coal fly ash from thermal power stations and a 2M NaOH solution at 100 degrees C. The Na-P1-type zeolite was formed with the reaction time of 6h at 100 degrees C, and its CEC value increased with an increase in the reaction time. The addition of a suitable amount of NaAlO2 to the fly ash was also effective for improving the CEC value. A new composite material consisting of the Na-P1-type zeolite and magnetite was synthesized from the fly ash and iron chlorides because the magnetic collection was possible using this composite material after radioactive Cs+ ion adsorption. The existence of nanosized magnetites in the polycrystalline zeolite (several micrometers) was confirmed by TEM observations. The CEC and magnetic property of these composite materials were characterized.

DOI： 10.1111/jace.12557

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Language：Japanese   Publishing type：Research paper (scientific journal)  

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Language：Japanese   Publisher：環境放射能除染学会  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

For the decontamination of radioactive Cs-134 and Cs-137 using magnetic collection, a new composite material consisting of a Na-P1-type zeolite and magnetite was synthesized from the waste fly-ash from thermal power stations and iron chlorides. The presence of nanosized magnetites in the polycrystalline zeolite (several micrometers) was confirmed by TEM observations. The cation-exchange capacity (CEC) and magnetic properties of these composite materials were characterized.

DOI： 10.1246/cl.130123

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DOI： 10.3379/msjmag.1303R011

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

For application as a novel ablation therapy of human cancer, the heating property of a Ti-coated mild steel rod was studied in an AC magnetic field at 300 kHz. When the Ti-tube thickness was as low as 0.1 mm, the specimen, when placed parallel to the magnetic flux direction (theta=0 degrees), exhibited a significant increase in temperature; however, its value gradually decreased with the increasing Ti thickness. In computer simulation images, the high magnetic flux concentration and concurrent large current density were observed around the interface between the mild steel rod and the Ti-tube. The heating property was drastically different at the three inclination angles (theta=0 degrees, 45 degrees, and 90 degrees) to the magnetic flux direction. However, the effect of the inclination angle was markedly reduced in the mild steel rod surrounded by a 0.3 mm thick Ti-tube, suggesting that the non-oriented heating property will be achieved for the prototype ablation needle coated with a Ti layer having the optimum thickness. (c) 2012 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jmmm.2012.11.025

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DOI： 10.3379/msjmag.1303R010

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For the purpose of developing a novel ablation therapy for oral cancer, the heat generation and transfer properties of a Ti-coated carbon steel rod with 20-mm length and 1.8-mm outer diameter were investigated by means of a high-frequency induction technique at 300 kHz. The heat generation measurement performed using water (15 mL) revealed that the difference of the inclination angles (θ = 0°, 45° and 90°) relative to the magnetic flux direction only slightly affects the heating behavior, exhibiting the overlapped temperature curves during an induction time of 1200 s. These results suggest that the effect of the shape magnetic anisotropy is almost eliminated, being convenient for the precise control of the ablation temperature in clinical use. In the experiments utilizing a tissue-mimicking phantom, the heat transfer concentrically occurred in the lateral direction for both the planar surface and a 10-mm deep cross-section. However, the former exhibited a considerably lower increase in temperature (ΔT), probably due to the effect of heat dissipation to the ambient air. No significant heat transfer was found to occur to the lower side of the inserted Ti-coated carbon steel rod, which is situated in the longitudinal direction.

DOI： 10.3390/jfb4010027

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

A superparamagnetic magnetic Y3Fe5O12 ferrite of 20.5 nm in particle size was prepared by bead milling using 0.05 mm phi beads for 10 h. The heat generation ability in an AC magnetic field (370 kHz, 1.77 kA-m(-1)) was 0.34 W.g(-1) for the bead-milled sample and was improved by calcination at low temperature. The main reason for this heat generation property of the milled samples was ascribed to a Neel relaxation of the superparamagnetic material. The maximum ability of 0.46 W.g(-1) in an AC magnetic field (370 kHz, 1.77 kA.m(-1)) was obtained for the sample (36.8 nm in particle size) calcined at 700 degrees C. The heat generation ability was decreased with particle growth when the calcination temperature was higher than 700 degrees C. For the sample calcined at 600 degrees C, the heat generation ability (W.g(-1)) was proportional to the square of the magnetic field (H/kA-m(-1)). In the case of the calcination at 700 degrees C, the heat generation ability (W.g(-1)) depended on the cube of the magnetic field. The heat generation mechanism would change from superparamagnetic to ferrimagnetic due to the pariticle growth at 700 degrees C. (C)2013 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.121.13

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A heteronuclear (NH4)2Sr[FeII(CN) 6] complex having a tetragonal phase was synthesized from Sr(NO 3)2 and (NH4)4[Fe II(CN)6]· nH2O. A single phase of the heteronuclear (NH4)2XLa1-XSr X[Fe(CN)6]·nH2O complex was synthesized by the coprecipitation for two heteronuclear hexacyano complexes of La[Fe III(CN)6]·5H2O and (NH4) 2Sr[FeII(CN)6]. In this chemical method, the X value (Sr content) for the complex was lower than that of the starting material. This (NH4)2XLa1-XSrX[Fe(CN) 6]·nH2O complex was also obtained by a mechanochemical reaction using a planetary ball-mill for two complexes (Total 0.01 mol = ca. 4g) of (1 - X)La-[FeIII(CN)6] ·5H2O and X(NH4)2Sr[Fe II(CN)6] with a small amount (5ml) of methanol. The hydration number calculated from the elemental analysis agreed with the estimated values when a hexagonal single (NH4)0.8La 0.6Sr0.4[Fe(CN)6]·4.2H2O phase formed for X = 0.4. This reaction for X = 0.4 was also possible for the dry process without methanol. In the case of X &gt
0.4, the peaks of the SrFe-complex were observed in the XRD pattern. The perovskite phase was directly formed by the thermal decomposition at a low temperature for the milled X = 0.4 complex. © 2013 The Ceramic Society of Japan.

DOI： 10.2109/jcersj2.121.21

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

A new heteronuclear (NH4)(2)Sr[Fe-II(CN)(6)] complex having a tetragonal phase was synthesized from Sr(NO3)(2) and (NH4)(4)[Fe-II(CN)(6)]center dot nH(2)O. A single phase of the heteronuclear (NH4)(2X)La1 - XSrX[Fe(CN)(6)]center dot nH(2)O complex was synthesized by the coprecipitation of two heteronuclear hexacyano complexes of La[Fe-III(CN)(6)]center dot 5H(2)O and (NH4)(2)Sr[Fe-II(CN)(6)]. The X value (Sr content) for the complex was lower than that of the starting material. The perovskite-type La1 - XSrXFeO3 (-) (alpha) phase was directly formed by the thermal decomposition even at 250 degrees C for 1 h. (C) 2012 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.matlet.2012.06.002

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Nano-sized magnetic Y3Fe5O12 ferrite having a high heat generation ability in an AC magnetic field was prepared by bead milling. A commercial powder sample (non-milled sample) of ca. 2.9 mu m in particle size did not show any temperature enhancement in the AC magnetic field. The heat generation ability in the AC magnetic field improved with a decrease in the average crystallite size for the bead-milled Y3Fe5O12 ferrites. The highest heat ability in the AC magnetic field was for the fine Y3Fe5O12 powder with a 15-nm crystallite size (the samples were milled for 4 h using 0.1 mm phi beads). The heat generation ability of the excessively milled Y3Fe5O12 samples decreased. The main reason for the high heat generation property of the milled samples was ascribed to an increase in the Neel relaxation of the superparamagnetic material. The heat generation ability was not influenced by the concentration of the ferrite powder. For the samples milled for 4 h using 0.1 mm phi beads, the heat generation ability (W g(-1)) was estimated using a 3.58 x 10(-4) fH(2) frequency (f/kHz) and the magnetic field (H/kA m(-1)), which is the highest reported value of superparamagnetic materials. (C) 2012 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jmmm.2012.02.002

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New heteronuclear (NH4)REIII[Fe-II(CN)(6)]center dot nH(2)O complexes (RE = La, Ce, Pr, Nd, Sm, Gd, Dy, Y, Er, Lu) were synthesized and their thermal decomposition products were investigated. The crystal structure of (NH4)RE[Fe-II(CN)(6)]center dot nH(2)O would be a hexagonal unit cell (space group: P6(3)/m), which was the same as that of La[Fe-II(CN)(6)]center dot 5H(2)O. The hydration number n = 4 was estimated by TG results for all the RE complexes. The lattice constants depended on the ionic radius of the RE3+ ion for the heteronuclear complexes. The single phase of the perovskite type materials was directly obtained by decomposition of the heteronuclear complexes for RE = La, Pr, Nd, Sm, and Gd. A mixture of CeO2 and Fe2O3 was formed for RE = Ce because of its oxidation to Ce4+. In the case of RE = Dy, Y, Er, and Lu complexes, the perovskite type materials formed at higher temperature via, mixed oxides such as RE2O3 and RE4Fe5O13 due to the small RE3+ ionic radius. (C) 2011 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

DOI： 10.1016/j.ceramint.2011.10.085

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To develop a novel ablation therapy for human solid cancer, the heating properties of a ferromagnetic carbon steel rod and a prototype Ti-coated needle using this carbon steel rod, were investigated in several high-frequency outputs at 300 kHz. In the former, the heating property was drastically different among the three inclination angles (θ = 0°, 45° and 90°) relative to the magnetic flux direction as a result of the shape magnetic anisotropy. However, the effect of the inclination angles was completely eliminated in the latter. It is considered that the complete non-oriented heating property relative to the magnetic flux direction allows the precise control of the ablation temperature during minimally invasive thermotherapy without a lead-wire connected to a fiber-optic thermometer. This newly designed Ti-coated device will be suitable for clinical use combined with its superior biocompatibility for ablation treatments using high-frequency induction heating.

DOI： 10.3390/jfb3010163

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Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

Background and Aim: We have studied and reported the usefulness of tumor local chemohyperthermia at a low-grade temperature below 43 degrees C with docetaxel-embedded magnetoliposome (DML) and an applied alternating current magnetic field. However, the mechanisms of this treatment and the dynamics of the injected docetaxel were not investigated in our previous study. Thus, we investigated the interaction of chemotherapy and hyperthermia in the treated tumor. Methods: Human MKN45 gastric cancer cells were implanted in the hind limbs of Balb-c/ nu/ nu mice. DML, magnetite-loaded liposome, and docetaxel were injected into the tumors with or without being exposed to an alternating current magnetic field. Docetaxel and tumor necrosis factor-a concentrations, the cell cycle, and cell death rates in the tumor were examined. Results: Docetaxel concentrations were significantly higher in the DML-injected group than in the docetaxel-injected group 3 days after injection. A G2/ M peak was observed 1 day after treatment in the DML-injected and exposed group and the docetaxel-injected group, while it was observed 3 days after treatment in the DML-injected without heating group and the magnetite-loaded liposome group. The tumor cell death rate gradually increased in the DML-injected group, with or without being exposed, while it gradually decreased after its peak in other groups. The tumor necrosis factor-a concentration in the tumor treated with DML with heating remained at a high level on the 7th day after treatment, while it decreased after its peak in other groups. Conclusion: The antitumor effect of this treatment derives from a combination of hyperthermia and chemotherapy locally in the tumor.

DOI： 10.1111/j.1440-1746.2011.06972.x

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We found that the nano-sized Y3Fe5O12 powder prepared by bead milling has the highest heat generation ability in an AC magnetic field of reported superparamagnetic materials. The heat generation ability in an AC magnetic field was strongly improved by a decrease in the average crystallite size of the bead milled samples. The highest heat ability in the AC magnetic field was for the fine Y3Fe5O12 powder with ca. 15nm crystallite size (the samples milled for 4 h using 0.1 mm beads). The reasons for the high heat generation properties of the milled samples are ascribed to an increase in the Neel relaxation of the superparamagnetic material. The heat generation ability (W.g(-1)) can be estimated using a 3.58 x 10(-4)f.H-2 frequency (f/kHz) and the magnetic field (H/kA.m(-1)) for the sample milled for 4 h using 0.1mm phi beads.

DOI： 10.1111/j.1551-2916.2011.04879.x

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For the preparation of precursors for fine perovskite-type (0.05 mol) materials, the metal nitrates were completely dissolved in a water solution (total 100 ml) with organic solvent of ethylene glycol (EG), diethylene glycol (DEG), or glycerin (GL), and then dried at 120 degrees C. In the case of a La-Fe precursor without organic solvent, LaFeO(3) was not the main phase for the calcined materials even at 1000 degrees C. However, the LaFeO(3) single phase was obtained by mixing a small amount of organic solvent EG (&gt;= 10 ml), DEG(&gt;= 5 ml), and GL(&gt;= 5 ml) into the solution. In the case of EG, clear XRD peaks of the LaFeO(3) single phase were obtained by calcination even at 350 degrees C. A higher calcination temperature for the formation of the LaFeO(3) phase was needed with an increase in the amount of the mixed organic solvent. The oxygen in these organic molecules would act to coordinate to the metal ions instead of nitric acid ions to form a quasipolymer containing metal ions in a random position, because the nitrogen elemental ratio in the precursor decreased with the amount of added organic solvent. The elemental distribution of La and Fe was highly homogeneous for the decomposed sample. The La(1-x)Sr(x)MnO(3) system was also examined by this method using GL. A single perovskite-type phase formed even for calcination at 700 degrees C. (C) 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.matchemphys.2011.08.021

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Nano-sized FeFe2O4 ferrite powder having a heat generation ability in an AC magnetic field was prepared by bead milling for a thermal coagulation therapy application. A commercial powder sample (non-milled sample) of ca. 2.0 mu m in particle size showed a temperature enhancement (Delta T) of 3 degrees C in an AC magnetic field (powder weight 1.0g, 370 kHz, 1.77 kA m(-1)) in ambient air. The heat generation ability in the AC magnetic field improved with the milling time, i.e., due to a decrease in the average crystallite size for all the examined ferrites. The highest heat ability (Delta T = 26 degrees C) in the AC magnetic field in ambient air was for the fine FeFe2O4 powder with a 4.7 nm crystallite size (the samples were milled for 6 h using 0.1 mm phi beads). However, the heat generation ability decreased for the excessively milled FeFe2O4 samples having average crystallite sizes of less than ca. 4.0 nm. The heat generation of the samples showed some dependence on the hysteresis loss for the B-H magnetic property. The reasons for the high heat generation properties of the milled samples would be ascribed to an increase in the Neel relaxation of the superparamagnetic material. The hysteresis loss in the B-H magnetic curve would be generated as the magnetic moment rotates (Neel relaxation) within the crystal. The heat generation ability (Wg(-1)) can be estimated using a 1.07 x 10(-4) fH(2) frequency (f, kHz) and the magnetic field (H, kA m(-1)) for the samples milled for 6 h using 0.1 mm phi beads. Moreover, an improvement in the heating ability was obtained by calcination of the bead-milled sample at low temperature. The maximum heat generation (Delta T = 59 degrees C) ability in the AC magnetic field in ambient air was obtained at ca. 5.6 nm for the sample calcined at 500 degrees C. The heat generation ability (Wg(-1)) for this heat treated sample was 2.54 x 10(-4) fH(2). (C) 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.matchemphys.2011.05.061

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We found the most promising powder material for the application of the thermal coagulation therapy for the treatment of cancerous tissues. The maximum heat generation ability (Delta T = 40-77 degrees C, 370 kHz, 1.77 kA.m(-1)) was obtained for the powder materials by the calcination at 1100 degrees C for the Y3 - XGdXFe5O12 system. This Delta T value is higher than ca. Delta T = 30 degrees C in same magnetic field for fine FeFe2O4 particles as the candidate material for this type of therapy. The particle growth with the formation of the cubic single phase might influence to the high heat generation. As an unexpected result, the Gd3Fe5O12 (X=3) has no heat generation ability in an AC magnetic field. (C) 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.matlet.2011.02.034

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Biocompatible hybrid particles composed of hydroxyapatite (Ca-10(PO4)(6)(OH)(2), HAp) and ferrite (gamma-Fe2O3 and Fe3O4) were synthesized using a two-step procedure. First, the ferrite particles were synthesized by co-precipitation. Second, the suspension, which was composed of ferrite particles by a co-precipitation method, Ca(NO3)2, and H3PO4 aqueous solution with surfactant, was nebulized into mist ultrasonically. Then the mist was pyrolyzed at 1000 degrees C to synthesize HAp-ferrite hybrid particles. The molar ratio of Fe ion and HAp was (Fe2+ and Fe3+)/HAp=6. The synthesized hybrid particle was round and dimpled, and the average diameter of a secondary particle was 740 nm. The cross section of the synthesized hybrid particles revealed two phases: HAp and ferrite. The ferrite was coated with HAp. The synthesized hybrid particles show a saturation magnetization of 11.8 emu/g. The net saturation magnetization of the ferrite component was calculated as 32.5 emu/g. The temperature increase in the AC-magnetic field (370 kHz, 1.77 kA/m) was 9 degrees C with 3.4 g (the ferrite component was 1.0 g). These results show that synthesized hybrid particles are biocompatible and might be useful for magnetic transport and hyperthermia studies. (C) 2010 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jmmm.2010.11.080

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Nanosized MgFe2O4-based ferrite powder having heat generation ability in an AC magnetic field was prepared by bead milling and studied for thermal coagulation therapy applications. The crystal size and the particle size significantly decreased by bead milling. The heat generation ability in an AC magnetic field improved with the milling time, i.e. a decrease in crystal size. However, the heat generation ability decreased for excessively milled samples with crystal sizes of less than 5.5nm. The highest heat ability (Delta T34 degrees C) in the AC magnetic field (370kHz, 1.77kA/m) was obtained for fine MgFe2O4 powder having a ca. 6 nm crystalsize (the samples were milled for 6-8 h using 0.1 mm phi beads). The heat generation of the samples was closely related to hysteresis loss, a B-H magnetic property. The reason for the high heat generation properties of the samples milled for 6-8 h using 0.1 mm f beads was ascribed to the increase in hysteresis loss by the formation of a single domain. Moreover, the improvement in heating ability was obtained by calcination of the bead-milled sample at low temperature. In this case, the maximum heat generation (Delta=41 degrees C) ability was obtained for a ca. 11 nm crystal size sample was prepared by crystal growth during the sample calcination. On the other hand, the Delta T value for Mg0.5Ca0.5Fe2O4 was synthesized using a reverse precipitation method decreased by bead milling. (C) 2010 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jmmm.2010.10.010

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The heat generation ability of needle-type materials was studied for the application of thermal coagulation therapy in an AC magnetic field. Although the Ti tube without the MgFe2O4 powder or Ti rod showed poor heat generation abilities in an AC magnetic field, the temperature was significantly increased by the presence of ferrite powder in the Ti tube. We confirmed using a computer simulation that the eddy loss of the Ti tube was increased by the enhanced magnetic flux density due to the ferrite powder in the Ti tube. The heat generation of the ferrite filled Ti tube was increased by utilization of the quenched MgFe2O4 powder from elevated temperature. The relative magnetic permeability of the quenched ferrite was enhanced with the decrease in the inverse ratio of the cubic spinel structure. The heat generation ability was increased with the increase in the relative magnetic permeability of the Ti tube with ferrite powder. The calculated joule loss based on the experimental results showed an agreement with those using the computer simulation. © 2010 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jmmm.2010.08.035

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：IOP PUBLISHING LTD  

The Y3Fe5O12-based ferrite, i.e., Y3-XGdXFe5O12 system was synthesized using a reverse coprecipitation method for application of new thermal coagulation therapy using an AC magnetic field for the treatment of cancerous tissues. The mixed phase of the Y3Fe5O12-type orthorhombic and cubic materials without any impurities were obtained for this systems calcined at low temperature in XRD results. However the orthorhombic phase almost disappeared by the calcination at 1150 degrees C or higher temperature for all the X samples. The calcination temperature strongly influenced the heat generation ability. The maximum heat generation ability (Delta T= 40-63 degrees C, 370kHz, 1.77kA/m) was obtained for the powder materials sintered at 1100 degrees C for the Y3-XGdXFe5O12 system. The particle growth with the formation of the cubic single phase strongly influenced to the heat generation.

DOI： 10.1088/1757-899X/18/9/092010

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：EMERALD GROUP PUBLISHING LIMITED  

Purpose - The purpose of this paper is to develop a ferromagnetic needle adaptable for a novel ablation cancer therapy; the heat generation ability of the mild steel rod embedded into the Ti-tube having a different thickness was investigated in a high-frequency output at 300 kHz.Design/methodology/approach - The outer diameter and length of the Ti-tubes were 1.8 and 20 mm, respectively, while the inner diameter was varied from 1.6 to 0 mm. The mild steel rod was embedded in a Ti-tube for preparing the needle-type specimen. Their heat generation ability was examined by changing the inclination angle to the magnetic flux direction in a high-frequency coil.Findings - When the thickness of the Ti surrounding the mild steel rod was as low as 0.1 mm, the heat generation ability was drastically different among the three inclination angles (theta = 0 degrees, 45 degrees, and 90) to the magnetic flux direction due to the effect of the shape-induced magnetic anisotropy. However, the effect of the inclination angle was almost eliminated in the specimen surrounded by the 0.4 mm thick Ti, suggesting that the non-oriented heat generation property is achieved for the needle-type mild steel rod coated with Ti having the optimum thickness.Originality/value - The prototype ablation needle having a complete non-oriented heat generation ability was fabricated to use in subsequent animal experiments. It is considered that the newly designed Ti-coated device is useful in ablation treatments using a high-frequency induction heating.

DOI： 10.1108/03321641111152739

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

MgFe2O4 microspheres having a 20-32 mu m diameter range were prepared by a spray dryer using bead-milled nano-sized particles. A commercial powder having a several mu m particle size was bead-milled to an approximate 6.2 nm crystallite size. The microspheres were obtained using the spray dryer when the air pressure was low (0.03 MPa). The yield of the MgFe2O4 20-32 mu m microspheres was improved by combination of a low air pressure and high ferrite concentration in the slurry. The heat generation ability in an AC magnetic field (370 kHz, 1.77 kA/m) was improved by the bead milling. (C) 2010 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.118.1207

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Thermal decomposition of the coordination polymer, (NH4)La[Fe-II(CN)(6)]center dot 4.5H(2)O, with a three-dimensional network structure formed by the Fe-II-CN-La-III linkages, was investigated. The decomposition began at around 323 K and proceeded via a few steps to give the anhydride complex, (NH4)La[Fe-II(CN)(6)], at around 523 K. Further heating gave rise to an abrupt collapse of cyanide groups at around 573 K, followed by the initial formation of the perovskite-type oxide, LaFeO3, at 603 K and the completion of the decomposition to produce LaFeO3 at around 898 K. Any formation of the component metal oxides, La2O3 and Fe2O3, was not recognized during the decomposition. From the XRD line broadening using Scherrer's equation, the average size of the thermal decomposition product was evaluated to be 21, 22, 25 and 30 nm at 773, 823, 898 and 1073 K, respectively. The specific surface area of the LaFeO3 particles prepared at 898, 1073 and 1273 K was 13.2, 8.6 and 2.5 m(2) g(-1), respectively. (C) 2010 The Ceramic Society of Japan. All rights reserved

DOI： 10.2109/jcersj2.118.384

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Hyperthermia is a minimally invasive approach to cancer treatment, but it is difficult to heat only the tumor without damaging surrounding tissue. To solve this problem, we studied the effectiveness of chemohyperthermia with docetaxel-embedded magnetoliposomes (DMLs) and an applied alternating current (AC) magnetic field. Human MKN45 gastric cancer cells were implanted in the hind limb of Balb-c/nu/nu mice. Various concentrations of docetaxel-embedded DMLs were injected into the tumors and exposed to an AC magnetic field (n = 6, each). For comparison with hyperthermia alone, magnetite-loaded liposome (ML)-injected tumors were exposed to an AC magnetic field. Furthermore, the results of DML without AC treatment and docetaxel diluted into PBS with AC treatment were also compared (n = 10, each). Tumor surface temperature was maintained between 42 and 43 degrees C. Tumor volume was reduced in the DML group with a docetaxel concentration > 56.8 microg/ml, while a docetaxel concentration > 568.5 microg/ml was required for tumor reduction without hyperthermia. Statistically significant differences in tumor volume and survival rate were observed between the DML group exposed to the magnetic field and the other groups. The tumor disappeared in 3 mice in the DML group exposed to the magnetic field; 2 mice survived over 6 months after treatment, whereas all mice of the other groups died by 15 weeks. Histologically, hyperthermia with DML damaged tumor cells and DML diffused homogeneously. To the best of our knowledge, this is the first report to show that hyperthermia using chemotherapeutic agent-embedded magnetoliposomes has an anticancer effect.

DOI： 10.1002/ijc.24864

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

The metal nitrates were completely dissolved in a mixed solvent (total 100 nil) of ethylene glycol (EG) (0, 5, 10, 15, 25, and 50 ml) and water, and then dried at 120 degrees C to make precursors for the fine LaFeO3 (0.05 mol) material. The main product was not LaFeO3 for the precursor prepared using the nitrate solution containing a small amount of EG (less than 5 ml). The mixed solution of the 10-15 ml EG with water was suitable for the preparation of 0.05 mol LaFeO3. In this case, clear XRD peaks of LaFeO3 single phase were obtained by the calcination even at 350 degrees C using this method. The higher calcination temperature for the formation of the LaFeO3 phase was needed due to the increased EG amount in the solvent. The particle size was ca. 40 nm for the (EG 10 ml) samples calcined at 350-600 degrees C and it increased with an increase in the calcining temperature. (C) 2009 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.117.1048

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

The reactivity of a newly developed oxygen ionic conductor, Nd-9.83(SiO4)(4.5)(AlO4)(1.5)O-2, with alkali carbonates was examined in air and CO2. The reactivity of the developed ionic conductor was substantially lower than that of ZrO2, 3YSZ and 8YSZ in air and also in CO2. It is concluded that this newly developed oxide is more tolerant to the alkali contamination and is applicable as a potentiometric oxygen concentration gas sensor. (C) 2009 The Ceramic society of Japan, All rights reserved.

DOI： 10.2109/jcersj2.117.175

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：INFORMA HEALTHCARE  

Purpose: This study investigated the efficacy of repeated thermotherapy for breast cancer utilising a novel sintered MgFe2O4 needle and alternating current (AC) magnetic field in xenograft animal models mimicking human breast cancer.
Materials and methods: A sintered MgFe2O4 needle and an apparatus to apply an AC magnetic field were prepared for this study. Animals bearing BT-474 tumours (mean (+/- standard deviation) volume, 471 +/- 153 mm(3)) were divided into four groups. A sintered MgFe2O4 needle (length, 5 mm) was placed in the centre of each tumour. An AC magnetic field (amplitude, 4 kA/m; 2 kW; 540 kHz) was applied for 10 min once, twice or three times for the first, second and third groups, respectively, and was not applied for the control group. Temperature during treatment and tumour volume 8 weeks after first treatment were assessed.
Results: Maximum tumour temperature tended to increase in repeated-application groups: group 1, 59.2 +/- 4 degrees C; group 2, 58.9 +/- 3.3 degrees C and 61.2 +/- 8.9 degrees C for the first and second applications; and group 3, 60.4 +/- 4.6 degrees C, 62.1 +/- 7.8 degrees C and 71.1 +/- 6.1 degrees C for the first, second and third applications. Tumour volumes in control, groups 1, 2 and 3 at 8 weeks after treatment were 3633 +/- 2478 mm(3), 3240 +/- 1031 mm(3), 1252 +/- 1289 mm(3) and 0 mm(3), respectively. Tumours were significantly smaller in group 3 than in the control and group 1 at 8 weeks.
Conclusions: The efficacy of repeated inductive heating utilising a sintered MgFe2O4 needle was demonstrated. Thermotherapy using the present method may offer an effective non-surgical treatment for human breast cancer.

DOI： 10.1080/02656730902991459

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：IOS PRESS  

Magnetic metal particles are known to induce heat energy under an alternating magnetic field (AMF). We developed a local tumor-heating device incorporating an MgFe2O4 needle for the purpose of mild ablation for cancer treatment. A needle made from sintered MgFe2O4 particles was embedded in the hepatic or breast tumors. Tumors were then heated by the energy dissipated from the needle exposed to an AMF. We sequentially evaluated histological changes, cellular activity of tumors, and the extent of thermal effect using nicotinamide adenine dinucleotide (NADH) diaphorase and terminal deoxynucleotidyl tranferase-mediated digoxigenin-DUTP nick-end labeling (TUNEL) staining. The mean temperature of the tumor tissue during heating was about 60 degrees C. Nuclei of the tumor cells became hyper-chromatin immediately after heating. The injured area spread progressively until 3 days after heating; when the area was surrounded by fibroblasts (meaning is not clear). Tumors disappeared after treatment without complications. This is the first time that the complete death of tumor cells has been realized by raising the tumor temperature above 60 degrees C using the heat generated by magnetic metal particles exposed to AMF. This device may be useful in the future for local hyperthemic treatment of human cancers.

DOI： 10.3233/BME-2009-0569

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Language：Japanese   Publisher：日本材料科学会  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER SCIENTIFIC PUBLISHERS  

Highly dense NASICON (Na1+xZr2SixP3-xO12, x = 2 and 3) electrolytes were synthesized using a sol-gel method for application in a CO2 as sensor. The conductivity decreased by increasing the x value from 2 and 3. The x = 2 material is reactive to alkali carbonate (M2CO3, M = Li and Na) at 600 degrees C by forming the alkali rich NASICON. In the case of x = 3, the NASICON phase in the mixture with Li carbonate and Na carbonate is stable even at 700 degrees C, since all the alkali ion sites in the NASICON are filled by Na+ ions for x = 3. We confirmed that the EMF drift for the CO2 gas sensor using the x = 3 electrolyte is lower than that using the x = 2 electrolyte.

DOI： 10.1166/sl.2008.544

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA  

New magnetic materials having a potentially high heat generation ability in an ac magnetic field were studied for application in thermal coagulation therapy. The Mg1-xCaxFe2O4 ferrites with X varied from 0 to 1.0 were synthesized using a reverse coprecipitation method. The obtained precursors were calcined at various temperatures in the range of 300-1000 degrees C with the intent to obtain fine ferrite powders. The heat generation in an ac magnetic field was very poor for X = 0. However, the heat generation improved with partial Ca2+ substitution of the Mg2+ sites. The maximum rise in temperature (Delta T) in the ac magnetic field (370kHz, 1.77 kA/m) was ca. 50 degrees C for the samples with 1.0g in weight and 0.2-0.8 in X of Mg1-xCaxFe2O4. Especially, the samples calcined at 800 degrees C showed the highest heat generation. When the Ca2+-substituted samples were calcined at 900 degrees C, the heat generation was reduced due to decomposition into the two phases of the MgFe2O4-type cubic and CaFe2O4-type orthorhombic. In addition, the samples calcined at 300 degrees C also showed a high heat generation. Although the crystal and particle sizes increased with the calcination temperature, they did not influence the heat generation of this system. The heat generation of the samples was closely related to the hysteresis loss. The reason for the high heat generation properties of the samples calcined at 300 and 800 degrees C is ascribed to the increase in the hysteresis loss by distortion of the cubic crystal structure. (c) 2007 Elsevier B.V All rights reserved.

DOI： 10.1016/j.jallcom.2007.07.024

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Language：Japanese   Publisher：ティー・アイ・シィー  

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To study surface behaviors, MgFe2O4 ferrite materials having different grain sizes were synthesized by two different chemical methods, i.e., a polymerization method and a reverse coprecipitation method. The single phase of the cubic MgFe2O4 was confirmed by the X-ray diffraction method for both the precursors decomposed at 600-1000 °C except for a very small peak of Fe2O3 was detected for the samples calcined at 600 and 700 °C by the polymerization method. The crystal size and particle size increased with an increase in the sintering temperature using both methods. The conductance of the MgFe2O4 decreased when the atmosphere was changed from ambient air to air containing 10.0 ppm NO2. The conductance change, C = G(air)/G(10 ppm NO2), was reduced with an increase in the operating temperature. For the polymerization method, the maximum C-value was ca. 40 at 300 °C for the samples sintered at 900 °C. However, the samples sintered at 1000 °C showed a low conductance change in the 10 ppm NO2 gas, because the ratio of the O2 gas adsorption sites on the particle surface is smaller than those of the samples having a high C-value. The low Mg content on the surface affects the low ratio of the gas adsorption sites. For the reverse coprecipitation method, the particle size was smaller than that of the polymerization method. Although a stable conductance was obtained for the sample sintered at 900 and 1000 °C, its conductance change was less than that of the polymerization method. © 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.apsusc.2007.09.024

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：INT INST ANTICANCER RESEARCH  

Background: This study investigated a novel approach for tumor ablation therapy using an alternating magnetic field combined with a sintered MgFe(2)O(4) needle. This method differs from radiofrequency ablation (RFA) by dielectric heating with regard to the heating mechanism and improves some weak points of these conventional thermotherapies. Materials and Methods: Nude mice mimicking human breast cancer BT474 were treated using this method. The extent of tumor death was assessed after ablation. Results: Staining with hematoxylin and eosin showed gradual expansion of the pyknotic area until 48 h after ablation. Nicotinamide adenine dinucleotide diaphorase staining also showed complete tumor death by 48 h after treatment. The ablation area was well controlled and reablation was not necessary. The tumor could be completely controlled using this method without any risk of skin burn. Conclusion: This novel ablation therapy appeared to be more effective and less invasive for treatment of breast cancer treatment than RFA.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

The thermal stability of a mixture of Li2CO3 and rare earth oxide (R2O3) was examined under a dry condition. The heat-treatment of the mixture in CO2 ambience resulted in the formation of rare earth carbonates for R = La, Pr, Nd, Sm, Eu, and Gd except for Ho-Lu and Y. Lithiation of their rare earth dioxymonocarbonate, i.e., R2O2+2x(CO3)(1-x)Li-2x was confirmed for R = La, Pr, Nd, and Sm when the mixture was heated at 900 degrees C. The lithiation degree, x, was increased with an increase in the heat-treatment temperature in CO2 and was lower than 0.3. The stability of lithium rare earth dioxymonocarbonate decreased with the atomic number of the rare earth. The high reactivity of the light rare earth oxides with Li2CO3 would be attributed to that the large R3+-O2- distance for CN = 5 and 6 with an increase in the ionic [R3+]/[O2-] ratio for the rare earth oxides and is very similar with that of the rare earth dioxymonocarbonates. (c) 2007 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.jeurceramsoc.2007.06.013

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Language：English   Publisher：The Ceramic Society of Japan  

Surface morphology of perovskite-type oxide, LaFeO_3, prepared by thermal decomposition of Fe(III) La(III) heteronuclear coordination polymer, La [Fe(CN)_6]・nH_2O, was compared with those of LaFeO_3 obtained by two conventional preparation methods, solid-state reaction of Fe_2O_3 and La_2O_3 and pyrolysis of a co-precipitated {Fe(OH)_3+La(OH)_3} precursor. At 1273 K, the first method gave LaFeO_3 with submicrometer-sized pores being highly ordered. At the same temperature, the LaFeO_3 particles with various sizes from nano-to micrometer in diameter and the highly sintered LaFeO_3 were obtained by solid state reaction and co-precipitation method, respectively.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA  

Carbon dioxide sensing performance of gas sensors using a NASICON (Na3Zr2Si2PO12) solid electrolyte and a Li2CO3-based auxiliary phase was examined. Gradual changes (drifts) in the EMF level with time were observed for the sensor using only Li2CO3 as an auxiliary electrode. A new auxiliary electrode material based on Li2CO3 and Nd2O3 was developed to improve the sensing stability. The mixture of Li2CO3 and Nd2O2+2x(CO3)(1-x)Li-2x was stable to humidity. The Nd2O2+2x(CO3)(1-x)Li-2x phase between an auxiliary electrode and NASICON acted as a stable diffusion boundary layer. For the mixture of Na2CO3 and Nd2O3, a si in i I ar treatment induced formation of only Nd2O2CO3. A higher reactivity of the Li+ ions with Nd2O2CO3 and a lower reactivity of the Na' ions effectively stabilized the diffusion boundary layer. (C) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.snb.2007.03.032

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Surface morphology of perovskite-type oxide, LaFeO3, prepared by thermal decomposition of Fe(III)La(III) heteronuclear coordination polymer, La[Fe(CN)(6)] center dot nH(2)O, was compared with those of LaFeO3 obtained by two conventional preparation methods, solid-state reaction of Fe2O3 and La2O3 and pyrolysis of a co-precipitated [Fe(OH)(3) + La(OH)(3)] precursor. At 1273 K, the first method gave LaFeO3 with sub micro meter-sized pores being highly ordered. At the same temperature, the LaFeO3 particles with various sizes from nano-to micrometer in diameter and the highly sintered LaFeO3 were obtained by solid state reaction and co-precipitation method, respectively.

DOI： 10.2109/jcersj2.115.640

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Surface morphology of perovskite-type oxide, LaFeO3, prepared by thermal decomposition of Fe(III)La(III) heteronuclear coordination polymer, La[Fe(CN)(6)] center dot nH(2)O, was compared with those of LaFeO3 obtained by two conventional preparation methods, solid-state reaction of Fe2O3 and La2O3 and pyrolysis of a co-precipitated [Fe(OH)(3) + La(OH)(3)] precursor. At 1273 K, the first method gave LaFeO3 with sub micro meter-sized pores being highly ordered. At the same temperature, the LaFeO3 particles with various sizes from nano-to micrometer in diameter and the highly sintered LaFeO3 were obtained by solid state reaction and co-precipitation method, respectively.

DOI： 10.2109/jcersj2.115.640

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Language：English   Publisher：The Ceramic Society of Japan  

The heat-treatment of a mixture of Li_2CO_3 and R_2O_3 (R=La and Nd) in CO_2 induced the formation of a rare-earth oxycarbonate followed by the lithium incorporation into the rare-earth oxycarbonate during the heating process. The formed oxycarbonates were related to the hexagonal structure with P6_3mmc. The c-lattice parameter increased and the a-lattice parameter slightly decreased with an increase in the lithiation degree. The lithiation degree y for the R_2O_<2+2y>(CO_3)_<1-y>Li_<2y> system increased with an increase in the heat treatment temperature in CO_2.

DOI： 10.2109/jcersj.115.365

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Other Link： https://jlc.jst.go.jp/DN/JALC/00294201367?from=CiNii

Language：English   Publisher：社団法人日本セラミックス協会  

The heat-treatment of a mixture of Li2CO3 and R 2O3 (R = La and Nd) in CO2 induced the formation of a rare-earth oxycarbonate followed by the lithium incorporation into the rare-earth oxycarbonate during the heating process. The formed oxycarbonates were related to the hexagonal structure with P63mmc. The c-lattice parameter increased and the a-lattice parameter slightly decreased with an increase in the lithiation degree. The lithiation degree y for the R2O2+2y (CO3)1-yLi2y. system increased with an increase in the heat treatment temperature in CO 2.

DOI： 10.2109/jcersj.115.365

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

The heat-treatment of a mixture of Li2CO3 and R2O3 (R = La and Nd) in CO2 induced the formation of a rare-earth oxycarbonate followed by the lithium incorporation into the rare-earth oxycarbonate during the heating process. The formed oxyearbonates were related to the hexagonal structure with P6(3)mmc. The c-lattice parameter increased and the a-lattice parameter slightly decreased with an increase in the lithiation degree. The lithiation degree y for the R2O2+2y(CO3)(1-y)Li-2y system increased with an increase in the heat treatment temperature in CO2.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA  

Novel sensing materials of tri-metallic perovskite oxides, SmFe1-xCoxO3 (x = 0-1.0), were applied for a conductometric O-3 and NO2 gas sensor. Fine particles of the oxides were prepared by pyrolysis of corresponding cyano-complexes, Sm[Fe1-xCox(CN)(6)](.)4H(2)O. The conductivity in air increased with an increase in the Co content. This increment in the conductivity reduced the operating temperature for a reliable conductivity measurement from 250 degrees C for x = 0 to 150, 100 and 80 degrees C for x = 0.05, 0.1 and 0.15, respectively. Furthermore, the measurement at room temperature was possible for x &gt;= 0.2. In 0.4 ppm O-3, a large response (S &gt; 100) was obtained for x =0-0.15 at the above operating temperatures. While in 10 ppm NO2, the elements of x = 0.05-0.5 exhibited the maximal response at 200 degrees C. The Co-added oxides showed good response and recovery behavior, compared to SmFeO3 even at low temperature. (c) 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.snb.2006.06.001

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Language：Japanese   Publisher：化学センサ研究会  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS INC  

The purpose of this study is to elevate the temperature and induce necrosis tumor cells that include ferrite powder to 50-60 degrees C by applying an alternating magnetic field. The achieved temperature is higher when compared to the conventional hyperthermia methods. We performed an experiment in which a high-water content agar phantom that was used as a quasi-tissue had 50 nm-10 mu m magnesium ferrite (MgFe2O4) dispersed in it and was then heated to a level of 190-700 kHz. The results show that the temperature of the phantom is higher for higher frequencies, larger particle sizes, and higher quantities of dispersed ferrite powder. Also, taking into account heat generation due to the magnetic powder, heat generation due to tissue metabolism, and the cooling effect of the blood flow, we solved the thermal equation related to local thermal therapy. Small differences in the distribution of ferrite powder affect the temperature increase of the tissue and the area where cell necrosis is induced.

DOI： 10.1080/01457630701483711

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Language：English   Publisher：Ehime University  

Finer perovskite-type SmFe1-xCoxO3 oxides formed by the thermal decomposition of the corresponding heteronuclear hexacyano complexes. With an increase in the treatment temperature, the particle size increased from 20nm (350oC) to 400nm (1000oC). For SmFeO3 prepared by the pyrolysis of the complex at 900oC, the sensing characteristics were examined for O3, NO2, MEK, EtOH and C6H6. The conductance was responsible to sub-ppm level's ozone and the sensitivity decreased with an increase in the working temperature. The sensitivity to 0.1ppm ozone was ca.1000 at 250oC. The partial replacing of Fe with Co resulted an increase in the conductance and the sensitivity to ozone decreased with an increase in the Co content, i.e., the sensitivity of SmFe0.90Co0.10O3 at 100oC for 0.4ppm ozone was 200.

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Other Link： http://iyokan.lib.ehime-u.ac.jp/dspace/handle/iyokan/1475

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Language：English   Publisher：Japan Society of Applied Physics  

Needle-type materials were studied for the application of thermal coagulation therapy in an AC magnetic field. We found that the Ti tube filled with ferrite powder as the core had a high heat generation ability in an AC magnetic field. Although the Ti tube without the ferrite powder or Ti rod showed poor heat generation abilities, the temperature was significantly increased by the existence of ferrite powder in the tube. In this case, the ferrite powder seems to improve the eddy loss for the Ti tube. The maximum heat generation ability was obtained for the Ti tube that contained MgFe2O 4 powder in the examined Ti tube with some ferrites. © 2006 The Japan Society of Applied Physics.

DOI： 10.1143/jjap.45.8673

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Language：Japanese   Publishing type：Research paper (other academic)   Publisher：日本金属学会  

DOI： 10.2320/materia.45.664

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

Heteronuclear Bi1-xLax [Fe(CN)(6)]center dot nH(2)O complexes were synthesized, and their crystal structures and thermal decomposition process were investigated by X-ray diffraction (XRD), thermogravimetry analysis (TGA), Auger electron spectroscopy (AES) with scanning electron microscope (SEM), and transmission electron microscopy (TEM). The crystal system of the complexes was orthorhombic having n = 4 for x = 0-0.7 and was hexagonal having n = 5 for x = 1.0. Their mixture was confirmed for x = 0.8 and 0.9. The lattice parameters for the orthorhombic increased with increasing the x value for the complexes. The single phase of trimetallic perovskite-type Bi1-xLaxFeO3 was obtained by its thermal decomposition at low temperature. The crystal system was hexagonal for BiFeO3 (x = 0) and orthorhombic for x = 0.1-1.0. In the case of the decomposed perovskite sample, the lattice parameters decreased with increasing x values for Bi1-xLaxFeO3. The particle size was ca. 30 nm for Bi0.2La0.8FeO3 obtained by thermal decomposition at 500 degrees C and it grew with an increase in decomposition temperature. For the Bi0.5La0.5FeO3, AES showed that the elemental distributions of Bi, La, and Fe on the surface were very homogeneous for the sample decomposed at 700 degrees C.

DOI： 10.1007/s10853-006-0326-y

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Language：English   Publisher：公益社団法人日本セラミックス協会  

Reactivity of the mixed powder of Li_2CO_3 with several metal oxides (Y_2O_3, Al_2O_3, ZrO_2, SiO_2 and ZrSiO_4) in synthetic air and 100% CO_2 was examined to develop a high temperature repeatable CO_2 absorbent. The mixture of Li_2CO_3 and Y_2O_3 in molar ratio of 1:1 was stable in CO_2 up to 950℃ but decomposed to form LiYO_2 at around 850℃ in synthetic air (N_2 79%+O_2 21%, CO_2&lt;0.5 ppm). The newly formed LiYO_2 started to absorb the CO_2 at 300℃ with the reaction of 2LiYO_2+CO_2→Li_2CO_3+Y_2O_3. Since the mixture was fairly stable in CO_2 up to 980℃, the reversed reaction directed to CO_2 emission was not observed in CO_2. LiYO_2 is a new material for a CO_2 absorbent available in a wide range of temperature.

DOI： 10.2109/jcersj.114.648

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Reactivity of the mixed powder of Li2CO3 with several metal oxides (Y2O3, Al2O3, ZrO2, SiO2 and ZrSiO4) in synthetic air and 100% CO2 was examined to develop a high temperature repeatable CO2 absorbent. The mixture of Li2CO3 and Y2O3 in molar ratio of 1:1 was stable in CO2 up to 950 degrees C but decomposed to form LiYO2 at around 850 degrees C in synthetic air (N-2 79%+O-2 21%, CO2&lt;0.5 ppm). The newly formed LiYO2 started to absorb the CO2 at 300 degrees C with the reaction of 2LiYO(2)+CO2 -&gt; Li2CO3+Y2O3. Since the mixture was fairly stable in CO2 up to 980 degrees C, the reversed reaction directed to CO2 emission was not observed in CO2. LiYO2 is a new material for a CO2 absorbent available in a wide range of temperature.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

The purpose of this study is to investigate the thermal characteristics of Mg1-XCaXFe2O4 ferrite powder by applying AC magnetic field and to predict the effect of thermal coagulation in vivo. We found that heating characteristics of the ferrite powder became greater as the frequency through the 400 kHz to 700 kHz range. The highest heat generation was attained using 7-15 nm ferrite powder. We also carried out a heat transfer simulation in which we were able to demonstrate that this material has sufficient heat generating characteristics to thermally coagulate a tumor cell and that it is possible to predict the range of the coagulation from the present simulation. (c) 2006 Springer Science + Business Media, Inc.

DOI： 10.1007/s10853-006-6749-7

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA  

The compacted sinters of Ln(9.33+x/3)Si(6-x)Al(x)O(26) (0 &lt;= x &lt;= 2.0), (Ln=La, Nd and Sin) are composed of an apatite-like phase with a hexagonal structure. The existence of Ln(2)SiO(5) was confirmed for x &lt;= 1.0 as a minor product, but its formation was suppressed by the increasing Al-content. The densification of the sinters was also improved by partially replacing Si4+ with Al3+. For all the Ln systems, the highest ionic conductivity was observed at x=1.5 in ambient air. The compacted sinters were used as a potentiometric oxygen sensor. The concentration dependence of EMF was well expressed by the Nernst equation, Delta E-obs=(RT/nF) ln (P-O2(I)/P-O2(II)). Furthermore, the electron number n is comparable to the theoretical value of 4. The sensing characteristics of the sinters are comparable to those of the sensors with 3 and 8 mol% YSZ. (c) 2005 Published by Elsevier B.V.

DOI： 10.1016/j.snb.2005.10.009

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：JAPAN INST METALS  

Amorphous and crystallized calcium phosphate (Ca-P) coatings on Ti substrate have been investigated by X-ray photoelectron spectroscopy (XPS). The Ca-P coating on Ti substrate was performed by radio frequency magnetron sputtering of a sintered hydroxyapatite (HAp) target. As-sputtered Ca-P coating having 1.81 of Ca/P ratio was amorphous. Annealing the as-sputtered amorphous coating at 600 degrees C resulted in crystallized coating into HAp and tetracalcium phosphate (TTCP). The XPS profile of amorphous coating is almost the same as that of annealed coating. The XPS profile of oxygen in the amorphous coating shows that oxygen atom combines with both phosphorus and calcium atoms, indicating the amorphous coating contains fundamental chemical bonds of both HAp and TTCP.

DOI： 10.2320/jinstmet.70.330

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Language：Japanese   Publisher：愛媛大学  

An attempt has been made to obtain a medical material applicable to the ablation therapy of liver cancer. The heating property of the needle-shaped Mg-ferrite (MgFe2O4) prepared using a sintering technique was studied under an external AC magnetic field at 370 kHz. The increase in temperature (ΔT) was as high as 32℃ for the stick of 1.5 mm in diameter, while the complementary use of these three sticks achieved marked ΔT enhancement of 58℃. In a rabbit liver, high-frequency inductive heating of the needle-shaped Mg-ferrite resulted in the local destruction of the tissue due to coagulative necrosis.

CiNii Books

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA  

The heteronuclear Ln[Fe(CN)(6)]center dot nH(2)O (Ln=La, Gd, and Lu) complexes were synthesized by the mixing of (NH4)(3)[Fe(CN)(6)] and Ln(NO3)(3) methanol solutions as a new method. Their thermal decomposition products were then investigated. Although the yield of the Ln[Fe(CN)(6)]center dot nH(2)O complexes was ca. 20% for the well-known method in a water solution, it was improved to ca. 90% using this new method. The X-ray diffraction (XRD) patterns of the complexes agreed with those of the Ln[Fe(CN)(6)]center dot nH(2)O single phase for all the examined Ln systems. The LnFeO(3) single phase was obtained by the thermal decomposition of the synthesized heteronuclear complexes for Ln = La, Gd, and Lu. (c) 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jallcom.2004.11.095

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Language：Japanese   Publisher：化学センサ研究会  

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：The Japan Institute of Metals and Materials  

DOI： 10.2320/materia.45.664

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Language：Japanese   Publisher：公益財団法人 ホソカワ粉体工学振興財団  

DOI： 10.14356/hptf.05511

CiNii Research

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Ceramic Society of Japan  

Reactivity of the mixed powder of Li2CO3 with several metal oxides (Y2O3, Al2O3, ZrO 2, SiO2 and ZrSiO4) in synthetic air and 100%CO2 was examined to develop a high temperature repeatable CO 2 absorbent. The mixture of Li2CO3 and Y 2O3 in molar ratio of 1: 1 was stable in CO2 up to 950°C but decomposed to form LiYO2 at around 850°C in synthetic air (N2 79% + O2 21%, CO2 &lt
0.5 ppm). The newly formed LiYO2 started to absorb the CO2 at 300°C with the reaction of 2LiYO2 + CO2→Li 2CO3 + Y2O3. Since the mixture was fairly stable in CO2 up to 980°C, the reversed reaction directed to CO2 emission was not observed in CO2. LiYO2 is a new material for a CO2 absorbent available in a wide range of temperature.

DOI： 10.2109/jcersj.114.648

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELECTROCHEMICAL SOC JAPAN  

Potentiometric gas sensors using a Ni reference electrode closed in a Na+ conducting Na2O-Al2O3-4SiO(2) glass were investigated for detection Of CO2 and Cl-2 sensing. An electric potential for the reference electrode was fixed by utilization of the Ni reference electrode. For the CO2 Sensor using the Na2CO3 auxiliary phase and Ni reference electrode, the EMF responded to changes in the CO2 gas concentration between 10 ppm and 10000 ppm. The EMF of the CO2 sensor using the Ni reference electrode also responded to a decrease in the O-2 gas concentration. However, the EMF was not fixed when the Pt reference electrode was utilized instead of Ni. The O-2 gas concentration for the reference electrode would be equilibrated by the Ni, NiO, and oxygen diffused from the solid electrolyte. For the Cl-2 gas sensor using the NaCl auxiliary phase, the EMF responded even to low Cl-2 gas concentrations below 10 ppm and also a ppb-level gas under humid conditions.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELECTROCHEMICAL SOC JAPAN  

Potentiometric gas sensors using a Ni reference electrode closed in a Na+ conducting Na2O-Al2O3-4SiO(2) glass were investigated for detection Of CO2 and Cl-2 sensing. An electric potential for the reference electrode was fixed by utilization of the Ni reference electrode. For the CO2 Sensor using the Na2CO3 auxiliary phase and Ni reference electrode, the EMF responded to changes in the CO2 gas concentration between 10 ppm and 10000 ppm. The EMF of the CO2 sensor using the Ni reference electrode also responded to a decrease in the O-2 gas concentration. However, the EMF was not fixed when the Pt reference electrode was utilized instead of Ni. The O-2 gas concentration for the reference electrode would be equilibrated by the Ni, NiO, and oxygen diffused from the solid electrolyte. For the Cl-2 gas sensor using the NaCl auxiliary phase, the EMF responded even to low Cl-2 gas concentrations below 10 ppm and also a ppb-level gas under humid conditions.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA  

The conductance changes of SmFeO3 based p-type gas sensor with ozone in air with and without VOCs were examined. The conductance for this sensor was responsible in sub-ppm levels ozone at the temperatures above 240 degrees C and the sensitivity decreased with an increase in the working temperature. It is expected that the sensitivity in 0.01 ppm ozone estimated to be ca. 10 at 290 degrees C. The sensing characteristic is promising to monitor the environmental air quality regarding with ozone. The conductance for ozone was decreased by the contamination of same levels VOCs. This is mainly due to the decrease in actual concentration of ozone by the reaction with contaminated VOCs. The developed sensor is a very promising candidate for the detection of ozone in sub-ppm levels and for the contaminated levels with several VOCs in monitoring environment. (c) 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.snb.2004.10.059

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Nano-sized FeFe2O4 ferrite powder for local thermal coagulation therapy was synthesized by a reverse coprecipitation method. The crystal diameter for the samples from the reverse coprecipitation method was smaller than that from a normal coprecipitation method. The crystal diameter increased with an increase in the synthesized temperature for both methods. The maximum increasing temperature under the AC magnetic field was at around a 12 nm crystal diameter. The FeFe2O4 powder was oxidized to Fe2O3 by calcination at 600 degrees C in ambient air. The heating ability almost depended on the hysteresis loss value. Although the increased temperature under the AC magnetic field for the fresh FeFe2O4 sample was very close to that for the commercialized MgFe2O4 powder, it was gradually decreased for FeFe2O4 with time in ambient air. (c) 2005 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.materresbull.2005.03.014

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA  

The CO2 sensing characteristics of the Pt,Na2CO3/Na+-electrolyte//YSZ/Pt structure were examined under dry conditions. To achieve a good interconnection between YSZ and a dense electrolyte, the Na2O-Al2O3-4SiO(2) melt was used as the electrolyte. The electrolyte was stable in syn-air and also in 100% CO2. The sensing characteristics were strongly influenced by the preparation scheme of the auxiliary electrode with Na2CO3. For the sensor with the auxiliary electrode of Na2CO3 formed by the heating of a coated Vaseline mixture with Na2CO3, the tendency to increase the emf was depressed. This observed improvement was attributed to the reduced crystallization and aggregation of Na2CO3 particles due to the coexistence of the oxidized Vaseline in the forming procedure. (c) 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.snb.204.11.078

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

The thermal stability of solium aluminium silicates and their reactivity to alkali carbonates were investigated in view of their application as CO2 gas sensors. A nepheline phase was very stable, since the peak position of the X-ray diffraction pattern was hardly influenced by either heat treatment or humidification up to 800 degrees C. A distorted carnegieite phase (like-carnegieite) transformed into the nepheline phase at 500 degrees C under a humid condition, while under a dry condition, it was stable up to 800 degrees C but transformed into the nepheline phase at 900 degrees C. For mixtures with alkali carbonates, the nepheline phase was most stable even under the humid condition at temperatures below 500 degrees C. When the mixtures were heated at NOT, the nepheline phase reverted to the like-carnegieite phase and alkali silicates, such as Na2SiO3, Li2SiO3 and LOA, formed as by-products. For Na2O-Al2O3-4SiO(2) sintering mixtures with Li2CO3, the like-carnegieite phase transformed into the nepheline phase at 500 degrees C. The nepheline phase was stable up to 1000 degrees C even under the humid condition and LOA formed as a by-product.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

Fine Mg1-xCaxFe2O4 ferrite powders for local thermal coagulation therapy were synthesized by a reverse coprecipitation method. The enhancement of temperature under an AC magnetic field was improved by the partial Ca2+ substitution. A high heat ability was obtained for the samples calcined at 300 and 800 degrees C.

DOI： 10.1246/cl.2005.482

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

Selection of ferrite powder was carried out to realize a thermal coagulation technique in which tumors are locally heated by an application of alternating magnetic field from external coils. Magnesium ferrite (MgFe2O4) showed the largest increase in temperature (AT) under an alternating magnetic field in all the ferrites examined. For all the samples, AT value under alternating magnetic field was increased with an increase in frequency (200-500 kHz). The heating ability for the Mg-ferrite was ca. 1.4 W/g under alternating magnetic field of 4.0 kA/m (200 W, 370 kHz). The heating ability in alternating magnetic field was clearly depended on the magnitude of the hysteresis loss for the ferrite powder. (C) 2005 Springer Science + Business Media, Inc.

DOI： 10.1007/s10853-005-5698-x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Ceramic Society of Japan  

The thermal stability of solium aluminium silicates and their reactivity to alkali carbonates were investigated in view of their application as CO 2 gas sensors. A nepheline phase was very stable, since the peak position of the X-ray diffraction pattern was hardly influenced by either heat treatment or humidification up to 800°C. A distorted carnegieite phase (like-carnegieite) transformed into the nepheline phase at 500°C under a humid condition, while under a dry condition, it was stable up to 800°C but transformed into the nepheline phase at 900°C. For mixtures with alkali carbonates, the nepheline phase was most stable even under the humid condition at temperatures below 500°C. When the mixtures were heated at 600°C, the nepheline phase reverted to the like-carnegieite phase and alkali silicates, such as Na2SiO3, Li2SiO3 and Li 4SiO4, formed as by-products. For Na2O-Al 2O3-4SiO2 sintering mixtures with Li 2CO3, the like-carnegieite phase transformed into the nepheline phase at 500°C. The nepheline phase was stable up to 1000°C even under the humid condition and Li2SiO3 formed as a by-product.

DOI： 10.2109/jcersj.113.269

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To develop a monolithic type CO2 gas sensor with Pt,Li 2CO3/Na2O-Al2O3-4SiO 2//YSZ/Pt structure, the reactivity of Li2CO3 and Na2O-Al2O3-4SiO2 (NA4S) was examined. For a newly fabricated sensor with an auxiliary electrode with Li 2CO3, the EMF value increased with time in the initial period and then stable response for CO2 was observed at 460°C. The NA4S was composed with carnegieite-like phase and amorphous SiO2. In the dry condition, the NA4S sinter was stable in air and also in 100 %CO2 but reactive with Li2CO3. Li 2SiO4 and Li2SiO3 phases were detected for NA4S-Li2CO3 mixture heated at around 600°C. For the mixture of amorphous SiO2 and Li 2CO3, Li4SiO4 phase was observed at 600°C in a dry condition and Li2SiO3 phase at 500°C in a humid condition. The observed EMF shifts with time and humidification were interpretable in terms of the formation of lithium silicates and the decomposition of Li4SiO4 to Li 2SiO3.

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Nd10(SiO4)6O3 and Nd 9.33+x/3Si6-xAlxO26 (x=0 to x=2.0) with apatite-type crystal structure were synthesized by the solid-state reaction at 1600°C and the sintered discs were examined by XRD and SEM. Nd 10(SiO4)6O3 and Nd 9.33+x/3Si6-xAlxO26 (x=0 to x=1.0) solid electrolytes contained Nd2SiO5 as a minor product and the content decreased with an increase in the Al content. The single phase was obtained and sinterability was improved for x=1.5. The highest ionic conductivity in air was observed for x=1.5 whose sample was applied for a potentiometric oxygen gas sensor. The concentration dependence of EMF was expressed by the Nernst&#039;s relationship and the electron number was estimated to 4.0 at 400°C and higher. The hysteresis of EMFs in an increasing and the decreasing for O2 gas concentration was also determined and its degree monotonically decreased with an increase in the operating temperature.

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To develop a stable solid-state lithium ionic conductor for potentiometric CO2 gas sensor, LixNd10-xSi6O 27-x (x=1-3) sinters were prepared. The x=2 and 3 sinters formed single phases, while a trace of Li2SiO3 phase was confirmed for x=1. The dense electrolyte was formed for Li2Nd 8Si6O25 by sintering at 1300°C while for the other examined materials, were porous. Li2CO3 mixed with the Li2Nd8Si6O25 was remarkably stable and not decomposed until ca. 950°C. For comparison, single decomposition of the Li2CO3 was observed at 700°C. It is expected that the Li2CO3 phase as an auxiliary electrode formed of the electrolyte with Li2Nd8Si 6O25 is stable at the working temperature of the potentiometric CO2 sensor with the structure of CO2, Pt/Li2CO3/Li+-conductor/Pt, ref. gas. The EMF change was explained by the Nernst&#039;s equation, E=Eo- (RT/nF)ln(Pco2) and the electron number, n, was slightly higher than 2 in the temperature range of 400°C and 500°C.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

Fluorescent properties of Eu(III) in the bulk- and nanocrystals of coordination polymer, Eu[Co(CN)(6)].4H(2)O, were compared with those of EuCl3.6H(2)O. Fluorescent intensity of bulk crystals was greatly enhanced on forming the coordination polymer, whereas that of nanocrystals was little affected. These results were discussed considering the coordination surroundings around Eu(III) located on the crystal surface.

DOI： 10.1246/cl.2004.1182

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

In order to realize a thermal coagulation technique in which tumors are locally heated up to 60-80 degreesC by inductive heating and necrotized, selection of ferrite powder and frequency are performed. We investigate the heating properties by applying AC magnetic field for various ferrite powders (micrometer size of the particles). The temperature rise for Mg-ferrite (MgFe2O4) powder is the largest around 360 kHz in our samples. It has sufficient heating ability for thermal coagulation therapy against cancer. (C) 2003 Elsevier B.V. All rights reserved.

DOI： 10.1016/j/jmmm.2003.12.591

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA  

CO2 sensing characteristics were examined in dry condition for Pt, Li2CO3/Na2O-Al2O3-4SiO(2) (NA4S)/YSZ/Pt structure. The electromotive force (emf) value was linearly increased with logarithm of CO2 concentration in the range of 10-10,000 ppm and the electron number was closed to 2.0. The electron number was hardly changed and the activity of alkali metal oxide in NA4S increased with time. As a reason to increase in the activity, the reaction of Li2CO3 as an auxiliary electrode with SiO2 in NA4S layer and the formation of lithium silicates are considered. The formation of Li2SiO3 was accelerated by using H2O, methanol or ethanol instead of alpha-terpineol as an additive for the mixing of Li2CO3 and silica. It was concluded that to depress the reaction with Li2CO3 and silica, the use of Li2CO3 mixed with alpha-terpineol for an auxiliary electrode was preferable. (C) 2003 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.snb.2003.11.002

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA  

CO(2) sensing characteristics were examined in dry condition for Pt, Na(2)CO(3)/Na(2)O-Al(2)O(3)-4SiO(2)//YSZ/Pt structure. After settled at the working temperature at 460degreesC, emf was gradually decreased with time and then increased. The drift to decrease the emf observed in the initial period is due to the remove of water in Na(2)CO(3) layer with morphological changes. The diffusion of Na ion in Na(2)O-Al(2)O(3)-4SiO(2) layer to YSZ layer is also one of the reason. The increase in the emf observed in the following period is due to the increase in the activity by the reaction of Na(2)CO(3) with SiO(2) in Na(2)O-Al(2)O(3)-4SiO(2) layer. Furthermore, it is confirmed that the reactivity of Na(2)CO(3) with SiO(2) is strongly affected by the preparation method/route of Na(2)CO(3) layer as an auxiliary electrode. (C) 2003 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.snb.2003.11.009

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Language：Japanese   Publisher：愛媛大学  

Selection of ferrite powder and suitable frequency were carried out to realize a thermal coagulation technique in which tumors are locally heated to 60-80℃ by an application of alternating magnetic field from external coils after they are stuffed with ferrite powder. Various ferrite powders were heated by an alternating magnetic field in 80kHz-399kHz. In this frequency range, the largest increase in temperature (ΔT) was obtained for the MgFe_2O_4 in all the samples examined. The ΔT value was almost proportional to the applied power and the weight of the powder. The heating ability for the Mg-ferrite was ca. 86 J・min^&lt;-1&gt;・g^&lt;-1&gt; under AC magnetic field (200W, 370kHz).

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA  

The conductance changes of SmFeO3-based p-type gas sensor and n-type SnO2 gas sensor (TGS2600), with volatile organic compounds (VOCs) and NO2 in air were examined. Prediction of the contaminated levels with VOCs became difficult when NO2 levels were changed and also vice versa. The use of one sensor was poor to detect a level of contaminated air&apos;s quality. By using at least two SmFeO3 sensor operating at a different temperature, prediction of each contaminated level with VOCs and NO2 became possible. Furthermore, by the combination with both sensor sub-ppm levels contamination with VOCs and NO2 was interpretable due to a higher sensitivity of TGS2600 for NO2 and of SmFeO3 for VOCs. (C) 2003 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.snb.2003.08.013

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

The monoclinic phase (P2(1)/n) was formed for 0 less than or equal to x less than or equal to 0.6 and the NASICON-type rhombohedral phase (R3c) was obtained for the region 0.8 less than or equal to x less than or equal to 1.2 in the Li3-2xCr2-xTax(PO4)(3) system. The activation energy for Li+ migration was ca. 0.45 eV for the monoclinic structure and ca. 0.36 eV for the rhombohedral structure. The maximum conductivity of 8.4 x 10(-6) S cm(-1) at 298 K was obtained for x = 0.8 of the Li3-2xCr2-xTax(PO4)(3) system. The conductivity of LiCrTa(PO4)(3) was enhanced about three to five times by the addition of the lithium salt due to the improvement of the sinterablity. The maximum conductivity was 2.4 x 10(-5) S cm(-1) at 298 K for LiCrTa(PO4)(3)-0.2Li(3)BO(3) (C) 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.ssi.2003.11.005

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

Solid-state NO2 sensors based on yttria stabilized zirconia (YSZ), an O2- conductor, combined either with an n- (WO3) or a p-type semiconducting oxide (LaFeO3) or a mixed electronic and ionic conductor (La0.8Sr0.2FeO3) were investigated. Platinum parallel finger electrodes were applied on the surface of tape-casted YSZ layers and attached with gold wires for current collection. Nanocrystalline perovskite powders were prepared using different chemical methods: LaFeO3 by the thermal decomposition of the LaFe-hexacyanide complex, and La0.8Sr0.2FeO3 by a sol-gel route. A sub-micrometric commercial WO3 powder was used. The oxide powders were mixed with a screen-printing oil and deposited on one Pt finger electrode. The presence of the oxide powder makes one of the electrodes different from the other in terms of catalytic activity, specific surface area, gas adsorption and reaction kinetics. Both electrodes were wholly exposed to the same gas atmosphere, without using reference air. The sensors were investigated at fixed temperature (450-700 degreesC) by measuring the electromotive force (EMF) at different concentrations of NO2 and CO in air in the range 20-1000 ppm. A fast and stable response was measured for all the tested sensors. An EMF of opposite sign was measured for p- and n-type semiconducting based sensors upon exposure to the same gas. After increasing the grain size of the nano-structured La0.8Sr0.2FeO3 powder by a heat treatment at 900 degreesC for 4 h, the response to NOx became small, slow and unstable. (C) 2003 Elsevier Ltd. All rights reserved.

DOI： 10.1016/0955-2219(03)00470-9

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Language：Japanese   Publisher：化学センサ研究会  

CiNii Books

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Language：Japanese   Publishing type：Research paper (other academic)  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

A heteronuclear complex, La2Cu(C4O4)(4)(H2O)(16)(.)2H(2)O, was synthesized and its thermal decomposition products were studied. Results of chemical analysis and TGA agreed with theoretical values for La2Cu(C4O4)(4)(H2O)(16)(.)2H(2)O complex. The La2CuO4 single phase having ca. 100 nm in crystal size was obtained by the thermal decomposition at 700 degreesC for 1 h.

DOI： 10.1246/cl.2003.906

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

A heteronuclear complex, La2Cu(C4O4)(4)(H2O)(16)(.)2H(2)O, was synthesized and its thermal decomposition products were studied. Results of chemical analysis and TGA agreed with theoretical values for La2Cu(C4O4)(4)(H2O)(16)(.)2H(2)O complex. The La2CuO4 single phase having ca. 100 nm in crystal size was obtained by the thermal decomposition at 700 degreesC for 1 h.

DOI： 10.1246/cl.2003.906

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Language：Japanese   Publisher：コンパス社  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA  

Finer perovskite-type LnFeO(3) (Ln = La, Nd, Sm, Gd, and Dy) powders were prepared by the thermal decomposition of heteronuclear complexes, Ln[Fe(CN)(6)].nH(2)O. The prepared LnFeO(3) showed a p-type semiconductive behavior and the highest enhancement of conductance due to NO2 exposure was observed for SmFeO3 sensor. The atomic ratio of adsorbed oxygen O-ad increased with the surface coverage of Ln, expressed as Ln/(Ln + Fe). Experimentally, the atomic ratio of Ln/(Ln + Fe) was estimated to around 0.6 and the largest value, 0.65, was observed for SmFeO3. For SmFeO3, the distance between the central Sm ion and nearest four ions of oxygen is comparable with the sum of crystal radius of Sm3+ (C.N. = 6) and O2-, and the distance between Sm ion and fifth and higher oxygen is longer than the expected length form Shannon&apos;s crystal radius. The observed longer length for C.N. = 5 or more is comparable to the length for Sm2+-O bond. The possible valence of Ln ion is directly related with the electron configuration of Ln species and only for Sm the existence of the divalent cation is expected. The divalency of the Sm3+ in the surface layer is suggested by the configurations of coordinated oxygen. The highest sensitivity for NO2 observed for SmFeO3 would be attributed to the formation of Fe defects due to the higher coverage of Ln and the divalency of Sm3+ in SmFeO3. (C) 2003 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0925-4005(03)00328-9

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

The heteronuclear LaNi(dhbaen)(NOAH(2)O)(n) complex was synthesized and its thermal decomposition products were analyzed by differential thermal analysis (TG/DTA), X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, Auger electron spectroscopy (AES) with scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Hexagonal perovskite-type LaNiO3 having fine particle size was obtained by sintering at 600 degreesC. AFS showed,that the elemental distributions of La, Ni, and O on the surface were very homogeneous for the sample decomposed at 900 degreesC. The LaNiO3 decomposed to La3Ni2O7 and NiO when the heating temperature increases up to 1000 degreesC. Heteronuclear LnNi(dhbaen)(NO3)H2O)(n) complexes (with Ln = Pr, Nd, Sm, and Gd) were also synthesized. The perovskite-type LnNiO(3) phase could not be formed by their thermal decomposition. (C) 2003 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0955-2219(02)00350-3

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Language：Japanese   Publisher：化学センサ研究会  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELECTROCHEMICAL SOC INC  

The influence of moisture in a test gas containing Cl-2 was investigated for a Cl-2 gas sensor using a NaCl-RuO2 mixed measuring electrode and a composite Na+ conductor of sodium superionic conductor, 40 wt % (Na2O-Al2O3-4SiO(2)). For dried Cl-2 gas, the electron number (n) for the reaction on the electrodes was 1.86 which was very close to the theoretical value n=2.0. When water vapor was added to the Cl-2 measuring gas, the electromotive force (emf) significantly decreased, since the Cl-2 gas concentration was reduced by the reaction with the H2O gas. Based on the calibration curve observed from the relationship between emf and Cl-2 concentration at 450degreesC under dry conditions, it is suggested that the sensor can determine parts per billion levels of Cl-2 gas under ambient conditions. Experimentally, the observed response time became faster with an increase in the flow rate and mainly depended on the exchange time of the test gas. (C) 2002 The Electrochemical Society.

DOI： 10.1149/1.1477210

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

The heteronuclear Bi1-xLax[Fe(CN)(6)].nH(2)O complexes were synthesized and their crystal structures were investigated by XRD and TGA. The crystal phase was hexagonal (n = 5) for x = 1.0, and orthorhombic (n = 4) for x = 0-0.7 and their mixture (x = 0.8 and 0.9). The lattice constants for the complexes linearly increased with an increase in the x value. The single phase of the trimetallic perovskite-type Bi0.5La0.5FeO3 was obtained by its thermal decomposition at 500degreesC.

DOI： 10.1246/cl.2002.568

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Chemical Society of Japan  

The heteronuclear Bi1-xLax[Fe(CN)6]·nH2O complexes were synthesized and their crystal structures were investigated by XRD and TGA. The crystal phase was hexagonal (n = 5) for x = 1.0, and orthorhombic (n = 4) for x = 0-0.7 and their mixture (x = 0.8 and 0.9). The lattice constants for the complexes linearly increased with an increase in the x value. The single phase of the trimetallic perovskite-type Bi0.5 La0.5FeO3 was obtained by its thermal decomposition at 500°C.

DOI： 10.1246/cl.2002.568

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

CO(2)-gas sensors were fabricated using NASICON-type dense ceramics with new compositions in the Na(3)Zr(2-(X/4))-Si(2-x)P(1+x)O(12) system. The bulk ceramics were prepared from sol-gel-processed powders. Dense electrolytes were obtained for compositions with x = 0.667 and x = 1.333. An improved sinterability was observed with respect to NASICON with conventional composition, which was attributed to liquid-phase sintering. The CO(2)-gas sensors using these dense samples showed a stable electromotive force (emf) response in dry atmosphere that was similar to the theoretical Nernstian value for a two-electron electrochemical reaction. This was observed also for the NASICON sample with composition x = 1.333 that showed a conductivity far lower than that of the NASICON with conventional composition. The emf changed quickly with changes of the CO(2-)gas concentration, and steady-state values were observed. The response time, in adsorption and desorption of CO(2), was very fast, especially at high CO(2) concentrations. The influence of humidity on the CO(2)-sensing performance was investigated. A lower sensitivity and slower response were obtained in humid CO(2) gas, especially at low CO(2) concentrations. CO(2)-sensing measurements at various gas-flow rates were performed to evaluate the reactions occurring at the measuring electrode. The occurrence of a side reaction on the measuring electrode was observed, i.e., the formation of sodium oxides. In dry gas, the reaction took place at low CO(2) concentrations and small now rates, whereas the reaction was strongly enhanced in humid environments and occurred over the entire CO(2) concentration range. However, the sensor performance recovered after switching from humid gas to dry gas. This demonstrated that the humidity affects the emf because of the Na(2)O(x) formation at the electrode, and, thus, the solid electrolyte itself was not degraded by humidity.

DOI： 10.1111/j.1151-2916.2002.tb00136.x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：INST PURE APPLIED PHYSICS  

To develop materials for achieving local hyperthermia, we investigate the heating of various ferrite and metal powders by applying an external AC magnetic field. In comparison with magnetite powder, which has often been used in previous experiments, Mg-ferrite powder is more applicable for achieving local hyperthermia.

DOI： 10.1143/JJAP.41.1620

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

CO(2)-gas sensors were fabricated using NASICON-type dense ceramics with new compositions in the Na(3)Zr(2-(X/4))-Si(2-x)P(1+x)O(12) system. The bulk ceramics were prepared from sol-gel-processed powders. Dense electrolytes were obtained for compositions with x = 0.667 and x = 1.333. An improved sinterability was observed with respect to NASICON with conventional composition, which was attributed to liquid-phase sintering. The CO(2)-gas sensors using these dense samples showed a stable electromotive force (emf) response in dry atmosphere that was similar to the theoretical Nernstian value for a two-electron electrochemical reaction. This was observed also for the NASICON sample with composition x = 1.333 that showed a conductivity far lower than that of the NASICON with conventional composition. The emf changed quickly with changes of the CO(2-)gas concentration, and steady-state values were observed. The response time, in adsorption and desorption of CO(2), was very fast, especially at high CO(2) concentrations. The influence of humidity on the CO(2)-sensing performance was investigated. A lower sensitivity and slower response were obtained in humid CO(2) gas, especially at low CO(2) concentrations. CO(2)-sensing measurements at various gas-flow rates were performed to evaluate the reactions occurring at the measuring electrode. The occurrence of a side reaction on the measuring electrode was observed, i.e., the formation of sodium oxides. In dry gas, the reaction took place at low CO(2) concentrations and small now rates, whereas the reaction was strongly enhanced in humid environments and occurred over the entire CO(2) concentration range. However, the sensor performance recovered after switching from humid gas to dry gas. This demonstrated that the humidity affects the emf because of the Na(2)O(x) formation at the electrode, and, thus, the solid electrolyte itself was not degraded by humidity.

DOI： 10.1111/j.1151-2916.2002.tb00136.x

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Language：Japanese   Publishing type：Research paper (other academic)  

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Language：Japanese   Publisher：ティ-・アイ・シ-  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MARCEL DEKKER INC  

The copper(II)-gadolinium(III) complex of a phenol-based side-off type di-nucleating ligand was newly synthesized, using N, N'-dimethyl-N,N'-ethylene-di(5-bromo-3-formyl-2-hydroxybenzylamine). Structural analysis revealed that one of the two formyl groups is converted into a hemiacetal group and the two dinuclear CuGd units are bridged by the alcoholic oxygens of acetal groups of each unit to construct the tetranuclear (CuGd)(2) core.

DOI： 10.1081/SIM-100107209

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

The heteronuclear LaMn(dhbaen)(OH)(NO3)(H2O)(4) complex was synthesized and perovskite-type hexagonal LaMnO3 was obtained by its thermal decomposition at approximately 700 degreesC, The complex and its decomposition products were analyzed using simultaneous thermogravimetric and differential thermal analysis (TG/DTA), X-ray diffraction (XRD) analysis, Fourier-transform infrared (FTIR) spectroscopy, Auger electron spectroscopy (AES), transmission electron microscopy (TEM) characterization, and specific surface area measurements. Although XRD analysis did not show the peaks of LaMnO3 for the sample sintered at 600 degreesC, the presence of polycrystalline LaMnO3 together with an amorphous phase was confirmed by TEM-selected area diffraction, Particle sizes of the samples decomposed at 600 degrees and 700 degreesC were 20 and 50 nm, respectively, For the conventional solid-state reaction method, XRD results showed the formation of a LaMnO3 single phase for the samples fired above 1000 degreesC, However, AES showed that the elemental distributions of La, Mn, and O on the surface were not homogeneous even for the sample sintered at 1200 degreesC. The thermal decomposition of the heteronuclear complex at low temperatures allows the synthesis of single-phase hexagonal LaMnO3 powders having nanosized particles, homogeneous and free of intragranular pores, which are suitable for electroceramics applications.

DOI： 10.1111/j.1151-2916.2001.tb00776.x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

The thermally decomposed products of the CuRE (dhbaen) (NO3) (dmso)(m)(H2O)(n) complex were investigated by differential thermal analysis (TGA), X-ray diffraction patterns (XRD), energy dispersive X-ray analysis (EDX), and X-ray photoelectron spectroscopy (XPS). A mixed phase of RE2O2SO4 and CuO was formed at a low temperature. The particle size of CuO in the mixed phase was estimated to be 30-90 nm by XRD. When the ionic radius of RE3+ ion is small, the RE2O2SO4 phase decomposed and formed a heterometallic RE2Cu2O5 at 850-1100 degreesC, It appears that one dmso directly interacted with the RE ion (RE-O = S(- CH3)(2)) for the complex and the RE-O = S bond remained as RE2O2SO4 after the decomposition. CuO in the mixed phase did not interact with - SO4 which was confirmed by XPS.

DOI： 10.2109/jcersj.109.1269_419

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

The heteronuclear LaMn(dhbaen)(OH)(NO3)(H2O)(4) complex was synthesized and perovskite-type hexagonal LaMnO3 was obtained by its thermal decomposition at approximately 700 degreesC, The complex and its decomposition products were analyzed using simultaneous thermogravimetric and differential thermal analysis (TG/DTA), X-ray diffraction (XRD) analysis, Fourier-transform infrared (FTIR) spectroscopy, Auger electron spectroscopy (AES), transmission electron microscopy (TEM) characterization, and specific surface area measurements. Although XRD analysis did not show the peaks of LaMnO3 for the sample sintered at 600 degreesC, the presence of polycrystalline LaMnO3 together with an amorphous phase was confirmed by TEM-selected area diffraction, Particle sizes of the samples decomposed at 600 degrees and 700 degreesC were 20 and 50 nm, respectively, For the conventional solid-state reaction method, XRD results showed the formation of a LaMnO3 single phase for the samples fired above 1000 degreesC, However, AES showed that the elemental distributions of La, Mn, and O on the surface were not homogeneous even for the sample sintered at 1200 degreesC. The thermal decomposition of the heteronuclear complex at low temperatures allows the synthesis of single-phase hexagonal LaMnO3 powders having nanosized particles, homogeneous and free of intragranular pores, which are suitable for electroceramics applications.

DOI： 10.1111/j.1151-2916.2001.tb00776.x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

Perovskite-type SmFeO3 powders were prepared by the thermal decomposition of a heteronuclear complex, Sm(Fe(CN)(6)). 4H(2)O and by solid-state reaction between the corresponding single oxides, Sm2O3 and Fe2O3. The thermal decomposition behavior of the complex was studied by thermogravimetric analysis. X-ray diffractometry was used to investigate the structure of the products from the complex thermal decomposition and the formation of SmFeO2 from the oxide mixture. Powders prepared by both methods were used to deposit thick films onto alumina substrates with comb-type gold electrodes. The microstructure and chemical homogeneity of the film surfaces,were investigated by scanning electron microscopy and Auger electron spectroscopy. Thick SmFeO3 single-phase films having a homogeneous elemental distribution on the surface were obtained when powder prepared by thermal decomposition of the complex was used for deposition, even when the powder was fired at low temperature (800 degreesC), Surface chemical analysis was performed by X-ray photoelectron spectroscopy (XPS), The O Is XPS line was deconvoluted into two peaks, attributed to adsorbed oxygen (O-ad) and oxygen in the lattice (O-lattice). Quantitative analysis showed that the surface coverage of iron, expressed as Fe/(Fe + Sm), was larger for the films prepared using the solid-state reacted powder. Although the O-lattice/(Fe + Sm) atomic ratio was not influenced by the processing procedures (and, thus, by iron surface coverage), the amount of O-ad decreased with increasing iron surface coverage, A model of the SmFeO3 surface was used to determine that the outermost layer of the perovskite-type SmFeO3 prepared from the complex consisted mainly of samarium ions that could each bond four adsorbed oxygen ions. A single oxygen ion could adsorb onto an iron ion, and therefore, the content of adsorbed oxygen was lower for the film prepared from the solid state reacted powders, which showed larger iron surface coverage. Electrical conductance measurements, performed with increasing temperature in different gaseous environments, confirmed these findings. Higher conductances and lower activation energies were observed for the films with larger samarium surface coverage.

DOI： 10.1111/j.1151-2916.2001.tb00660.x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

Perovskite-type SmFeO3 powders were prepared by the thermal decomposition of a heteronuclear complex, Sm(Fe(CN)(6)). 4H(2)O and by solid-state reaction between the corresponding single oxides, Sm2O3 and Fe2O3. The thermal decomposition behavior of the complex was studied by thermogravimetric analysis. X-ray diffractometry was used to investigate the structure of the products from the complex thermal decomposition and the formation of SmFeO2 from the oxide mixture. Powders prepared by both methods were used to deposit thick films onto alumina substrates with comb-type gold electrodes. The microstructure and chemical homogeneity of the film surfaces,were investigated by scanning electron microscopy and Auger electron spectroscopy. Thick SmFeO3 single-phase films having a homogeneous elemental distribution on the surface were obtained when powder prepared by thermal decomposition of the complex was used for deposition, even when the powder was fired at low temperature (800 degreesC), Surface chemical analysis was performed by X-ray photoelectron spectroscopy (XPS), The O Is XPS line was deconvoluted into two peaks, attributed to adsorbed oxygen (O-ad) and oxygen in the lattice (O-lattice). Quantitative analysis showed that the surface coverage of iron, expressed as Fe/(Fe + Sm), was larger for the films prepared using the solid-state reacted powder. Although the O-lattice/(Fe + Sm) atomic ratio was not influenced by the processing procedures (and, thus, by iron surface coverage), the amount of O-ad decreased with increasing iron surface coverage, A model of the SmFeO3 surface was used to determine that the outermost layer of the perovskite-type SmFeO3 prepared from the complex consisted mainly of samarium ions that could each bond four adsorbed oxygen ions. A single oxygen ion could adsorb onto an iron ion, and therefore, the content of adsorbed oxygen was lower for the film prepared from the solid state reacted powders, which showed larger iron surface coverage. Electrical conductance measurements, performed with increasing temperature in different gaseous environments, confirmed these findings. Higher conductances and lower activation energies were observed for the films with larger samarium surface coverage.

DOI： 10.1111/j.1151-2916.2001.tb00660.x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Ceramic Society of Japan  

The thermally decomposed products of the CuRE(dhbaen) (NO3) (dmso)m(H2O)n complex were investigated by differential thermal analysis (TGA), X-ray diffraction patterns (XRD), energy dispersive X-ray analysis (EDX), and X-ray photoelectron spectroscopy (XPS). A mixed phase of RE2O2SO4 and CuO was formed at a low temperature. The particle size of CuO in the fixed phase was estimated to be 30-90 nm by XRD. When the ionic radius of RE3+ ion is small, the RE2O2SO4 phase decomposed and formed a heterometallic RE2Cu2O5 at 850-1100°C. It appears that one dmso directly interacted with the RE ion (RE-O = S(-CH3)2) for the complex and the RE-O=S bond remained as RE2O2SO4 after the decomposition, CuO in the mixed phase did not interact with -SO4 which was confirmed by XPS.

DOI： 10.2109/jcersj.109.1269_419

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Ceramic Society of Japan  

The thermally decomposed products of the CuRE(dhbaen) (NO3) (dmso)m(H2O)n complex were investigated by differential thermal analysis (TGA), X-ray diffraction patterns (XRD), energy dispersive X-ray analysis (EDX), and X-ray photoelectron spectroscopy (XPS). A mixed phase of RE2O2SO4 and CuO was formed at a low temperature. The particle size of CuO in the fixed phase was estimated to be 30-90 nm by XRD. When the ionic radius of RE3+ ion is small, the RE2O2SO4 phase decomposed and formed a heterometallic RE2Cu2O5 at 850-1100°C. It appears that one dmso directly interacted with the RE ion (RE-O = S(-CH3)2) for the complex and the RE-O=S bond remained as RE2O2SO4 after the decomposition, CuO in the mixed phase did not interact with -SO4 which was confirmed by XPS.

DOI： 10.2109/jcersj.109.1269_419

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Perovskite-type LaFeO 3 powders were prepared by thermal decomposition of a heteronuclear complex, La[Fe(CN) 6]·4H 2O at 700°C. Powders were deposited as thick films on alumina substrates with comb-type Au electrodes and then sintered in nitrogen or air atmosphere. The surface chemical analysis was performed using X-ray photoelectron spectroscopy (XPS). The O1s XPS line was separated in two peaks attributed to adsorbed oxygen (O ad) and oxygen in the lattice (O lattice) on the surface. The ratio [O ad + O lattice]/[La + Fe] was uninfluenced by the ambient during sintering. The [O lattice]/[La+Fe] atomic ratio decreased and [O ad]/[La+Fe] value increased upon sintering in N 2 atmosphere, as compared with samples sintered in air. It was argued that O ad sites act as adsorption sites for nitrogen dioxide. The increase in O ad sites is effective for enhancing electrical conductivity in nitrogen dioxide.

DOI： 10.2109/jcersj.108.1262_892

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A composite material containing La 2CuO 4 and CuO was directly synthesized by thermal decomposition of a heteronuclear CuLa(dhbaen)(NO 3) -nH 2O complex, where dhbaen is N,N′-bis(3-hydroxysalicylidene)-ethylenediamine. The mean particle size was of the order of 200 nm for a sample decomposing at 800°C. The exposure to 7.8 ppm H 2S at 50°C for 6 d (the exposure gas was alternately changed from air to 7.8 ppm H 2S at 6 h intervals for 6 d) resulted in the formation of copper sulfide and lanthanum sulfate on the surface. At 100°C, the surfaces were mostly covered with both sulfide and sulfate. Lanthanum sulfate and copper sulfide, without copper sulfate, were formed at temperatures below 200°C. Copper sulfate was detected when the sample was exposed at 250°C. For samples exposed at 100°C, the atomic ratio determined by X-ray photoelectron spectroscopy (XPS) for [S (sulfate)]/[La] was 1.6 on the surface and decreased to 0.01 with increasing depth of Ar sputtering on the surface. The ratio of [S (sulfide)]/[Cu] was 0.99 on the surface and decreased to about 0.45 upon Ar sputtering. However, [S(sulfate)]/[La] and [S(sulfide)]/[Cu] ratios on the surface were 0.03 and 0.39, respectively, for single-phase La 2CuO 4 prepared by the solid state reaction method after the exposure. It is concluded that the reactions of Cu and La in La 2CuO 4 with hydrogen sulfide are accelerated by the presence of well-dispersed CuO.

DOI： 10.2109/jcersj.108.1264_1052

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Language：English   Publisher：社団法人日本セラミックス協会  

A composite material containing La_2CuO_4 and CuO was directly synthesized by thermal decomposition of a heteronuclear CuLa(dhbaen)(NO_3)・nH_2O complex, where dhbaen is N, N´-bis(3-hydroxysalicylidene)-ethylenediamine. The mean particle size was of the order of 200 nm for a sample decomposing at 800℃. The exposure to 7.8 ppm H_2S at 50℃ for 6 d (the exposure gas was alternately changed from air to 7.8 ppm H_2S at 6 h intervals for 6 d) resulted in the formation of copper sulfide and lanthanum surface on the surface. At 100℃, the surfaces were mostly covered with both sulfide and sulfate. Lanthanum sulfate and copper sulfide, without copper sulfate, were formed at temperatures below 200℃. Copper sulfate was detected when the sample was exposed at 250℃. For samples exposed at 100℃, the atomic ratio determined by X-ray photoelectron spectroscopy (XPS) for [S(sulfate)]/[La] was 1.6 on the surface and decreased to 0.01 with increasing depth of Ar sputtering on the surface. The ratio of [S(sulfide)]/[Cu] was 0.99 on the surface and decreased to about 0.45 upon Ar sputtering. However, [S(sulfate)]/[La] and [S(sulfide)]/[Cu] ratios on the surface were 0.03 and 0.39, respectively, for single-phase La_2CuO_4 prepared by the solid state reaction method after the exposure. It is concluded that the reactions of Cu and La in La_2CuO_4 with hydrogen sulfide are accelerated by the presence of well-dispersed CuO.

DOI： 10.2109/jcersj.108.1264_1052

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

Sol-gel processed NASICON-type with new compositions in the Na3Zr2-(x/4)Si2-xP1+xO12 system showed an improved sinterability with an increase in the x value. This is attributed to liquid phase sintering. This dense electrolyte system is suitable for the application as gas sensors. The CO2 gas sensors using highly dense x = 0.667 (sample B) and x = 1.333 (sample C) samples show a stable EMF response in dry atmosphere which is very close to the theoretical value. Although a lower sensitivity and slower response were obtained in humid CO2 gas, the sensor performance recovered after switching from humid gas to dry gas.

DOI： 10.1023/A:1008719801695

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

A composite material containing La2CuO4 and CuO was directly synthesized by thermal decomposition of a heteronuclear CuLa(dhbaen)(NO3) nH(2)O complex, where dhbaen is N,N'-bis (3-hydroxysalicylidene)-ethylenediamine. The mean particle size was of the order of 200 nm for a sample decomposing at 800 degreesC. The exposure to 7.8 ppm H2S at 50 degreesC for 6 d (the exposure gas was alternately changed from air to 7.8 ppm H2S at 6 h intervals for 6 d) resulted in the formation of copper sulfide and lanthanum sulfate on the surface. At 100 degreesC, the surfaces were mostly covered with both sulfide and sulfate. Lanthanum sulfate and copper sulfide, without copper sulfate, were formed at temperatures below 200 degreesC, Copper sulfate was detected when the sample was exposed at 250 degreesC. For samples exposed at 100 degreesC, the atomic ratio determined by X-ray photoelectron spectroscopy (XPS) for [S (sulfate)]/[La] was 1.6 on the surface and decreased to 0.01 with increasing depth of Ar sputtering on the surface. The ratio of [S (sulfide]/[Cu] was 0.99 on the surface and decreased to about 0.45 upon Ar sputtering, However, [S(sulfate)]/[La] and [S(sulfide)]/[Cu] ratios on the surface were 0.03 and 0.39, respectively, for single-phase La2CuO4 prepared by the solid state reaction method after the exposure. It is concluded that the reactions of Cu and La in La2CuO4 with hydrogen sulfide are accelerated by the presence of well-dispersed CuO.

DOI： 10.2109/jcersj.108.1264_1052

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

Powders and pellets of new NASICON compositions have been synthesized using a mixed inorganic-organic sol-gel synthesis, by the preliminary formation of a pre-hydrolized TEOS xerogel. The investigated compositions can be described by the general formula Na3Zr2-(x/4)Si2-xP1+xO12, obtained by keeping the Na concentration constant (= 3) at the optimum value reported for ionic conductivity, with x = 0 (the usual NASICON composition), 0.667, and 1.333. The xerogels were calcined at various temperatures in the range 400-1200 degreesC. The powder samples were analyzed by TG/DTA, BET measurements, XRD, and SEM. The powders calcined at 500 degreesC were sintered into pellets at 1100 degreesC for 6 h. The sintering behavior of the pellets was investigated by dilatometric measurements and SEM observations. The sinterability increased with increasing x value. Dense samples of the new compositions were obtained by sintering at only 1100 degreesC. This is attributed to the occurrence of liquid phase sintering. The electrical conductivity of the NASICON sintered bodies was measured by ac impedance spectroscopy. The conductivity decreased with decreasing c(0) lattice parameter of the hexagonal structure or increasing x value. The CO2 gas sensors, using as electrolyte the dense samples of the new NASICON compositions, showed good EMF response that was very close to the theoretical value, even for the sample with x = 1.333 that showed much lower conductivity.

DOI： 10.1023/A:1026543915883

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELECTROCHEMICAL SOC INC  

A composite Na+ conductor of polycrystalline NASICON mixed with glassy Na2O-Al2O3-4SiO(2) (40 wt%) was investigated and used for a Cl-2 gas sensor. The densification of the solid electrolyte was improved by the addition of the glassy material. The sensor probe using the composite electrolyte and RuO2 + NaCl (1:1) measuring electrode produced a rapid electromotive force (EMF) change for the Cl-2 gas concentration below 10 ppm at above 450 degreesC. For the low temperature of 400 degreesC, a slow EMF response was obtained due to the side reaction between the Cl-2, gas and Na2O on the solid electrolyte and/or slow Cl-2, reduction to Cl- ion on the electrode. This sensor EMF value in air was only slightly influenced by the changing of the O-2 or CO2 gas concentration. (C) 2000 The Electrochemical Society. S0013-4651(00)04-083-0. All nights reserved.

DOI： 10.1149/1.1394070

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Language：English   Publisher：社団法人日本セラミックス協会  

Perovskite-type LaFeO_3 powders were prepared by thermal decomposition of a heteronuclear complex, La[Fe(CN)_6]・4H_2O at 700℃. Powders were deposited as thick films on alumina substrates with comb-type Au electrodes and then sintered in nitrogen or air atmosphere. The surface chemical analysis was performed using X-ray photoelectron spectroscopy (XPS). The O1s XPS line was separated in two peaks attributed to adsorbed oxygen (O_&lt;ad&gt;) and oxygen in the lattice (O_&lt;lattice&gt;) on the surface. The ratio [O_&lt;ad&gt;+O_&lt;lattice&gt;]/[La+Fe] was uninfluenced by the ambient during sintering. The [O_&lt;lattice&gt;]/[La+Fe] atomic ratio decreased and [O_&lt;ad&gt;]/[La+Fe] value increased upon sintering in N_2 atmosphere, as compared with samples sintered in air. It was argued that O_&lt;ad&gt; sites act as adsorption sites for nitrogen dioxide. The increase in O_&lt;ad&gt; sites is effective for enhancing electrical conductivity in nitrogen dioxide.

DOI： 10.2109/jcersj.108.1262_892

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Perovskite-type LaFeO3 powders were prepared by thermal decomposition of a heteronuclear complex, La[Fe(CN)(6)]. 4H(2)O at 700 degreesC. Powders were deposited as thick films on alumina substrates with comb-type Au electrodes and then sintered in nitrogen or air atmosphere. The surface chemical analysis was performed using X-ray photoelectron spectroscopy (XPS). The Ols XPS line was separated in two peaks attributed to adsorbed oxygen (O-ad) and oxygen in the lattice (O-lattice) on the surface. The ratio [O-ad + O-lattice]/[La + Fe] was uninfluenced by the ambient during sintering. The [O-lattice]/[La + Fe] atomic ratio decreased and [O-ad]/ [La + Fe] value increased upon sintering in N-2 atmosphere, as compared with samples sintered in air. It was argued that O-ad sites act as adsorption sites for nitrogen dioxide. The increase in O-ad sites is effective for enhancing electrical conductivity in nitrogen dioxide.

DOI： 10.2109/jcersj.108.1262_892

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA  

High-conductivity and high-density samples with new compositions in the NASICON-type electrolyte series, i.e., the Na(3)Zr(2-(x/4))Si(2-x)P(1+x)O(12) system, with x = 0(A), 0.667(B), and 1.333(C) were synthesized using a mixed inorganic-organic sol-gel process. The sinterability was improved with increasing the x value, but the conductivity decreased. Highly dense samples were obtained by sintering at 1100 degrees C. The conductivity decreased with decreasing the c lattice parameter of the hexagonal structure. Nevertheless, the CO(2) gas sensors using the highly dense B and C samples showed good EMF response which is very close to the theoretical value. (C) 2000 Elsevier Science S.A. All rights reserved.

DOI： 10.1016/S0925-4005(99)00293-2

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CERAMIC SOC  

Ultrafine powders of trimetallic orthoferrites containing lanthanum and samarium in various ratios were synthesized by thermal decomposition at low temperatures of the corresponding hexacyano complexes to modulate the functional properties of these perovskite-type oxides. The precursors and their decomposition products were analyzed by simultaneous thermogravimetric and differential thermal analyses, X-ray diffractometry, and Raman spectroscopy. Single-phase trimetallic precursors and oxides were obtained. The crystal structure of the perovskite-type oxides was orthorhombic, and the lattice parameters were affected by the ionic size of the rare-earth elements present in the oxides. Raman spectra showed a broadening of the vibrational bands with increased lanthanum content, This was ascribed to some disorder in the oxygen sublattice, related to distortions of the cation-oxygen coordination, and to a reduction of the orthorhombic distortion in the unit-cell basal plane. Most of the Raman modes above 200 cm(-1), associated with the vibration of oxygen ions, showed a frequency increase with effective cation mass, defined as m(eff) = xm(La) + (1 - x)m(Sm), i.e., with samarium content, This was explained by assuming that the force constants increased with decreased Ln-O and Fe-O interatomic distances observed for high samarium content.

DOI： 10.1111/j.1151-2916.2000.tb01335.x

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Ultrafine powders of trimetallic orthoferrites containing lanthanum and samarium in various ratios were synthesized by thermal decomposition at low temperatures of the corresponding hexacyano complexes to modulate the functional properties of these perovskite-type oxides. The precursors and their decomposition products were analyzed by simultaneous thermogravimetric and differential thermal analyses, X-ray diffractometry, and Raman spectroscopy. Single-phase trimetallic precursors and oxides were obtained. The crystal structure of the perovskite-type oxides was orthorhombic, and the lattice parameters were affected by the ionic size of the rare-earth elements present in the oxides. Raman spectra showed a broadening of the vibrational bands with increased lanthanum content. This was ascribed to some disorder in the oxygen sublattice, related to distortions of the cation-oxygen coordination, and to a reduction of the orthorhombic distortion in the unit-cell basal plane. Most of the Raman modes above 200 cm-1, associated with the vibration of oxygen ions, showed a frequency increase with effective cation mass, defined as meff = xmLa + (1 - x) mSm, i.e., with samarium content. This was explained by assuming that the force constants increased with decreased Ln-O and Fe-O interatomic distances observed for high samarium content.

DOI： 10.1111/j.1151-2916.2000.tb01335.x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

A composite Na+ conductor of polycrystalline NASICON mixed with a glassy Na2O-Al2O3-4SiO(2) (40wt%) was used in Cl-2 gas sensor. The probe using the composite electrolyte and a RuO2+NaCl (1:1) measuring electrode gave rapid EMF changes even for sub-ppm level of Cl-2 gas concentration (below 6 ppm).

DOI： 10.1246/cl.2000.34

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Chemical Society of Japan  

A composite Na+ conductor of polycrystalline NASICON mixed with a glassy Na2O-Al2O3-4SiO2 (40wt%) was used in Cl2, gas sensor. The probe using the composite electrolyte and a RuO2+NaCl (1:1) measuring electrode gave rapid EMF changes even for sub-ppm level of Cl2 gas concentration (below 6 ppm).

DOI： 10.1246/cl.2000.34

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DOI： 10.2109/jcersj.108.1264_1052

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

The heteronuclear LaMn(dhbaen)(OH)(NO3)(H2O), complex was synthesized and perovskite-type hexagonal LaMnO3 was obtained by its thermal decomposition at 700 degrees C. Particle size of the samples decomposed at 600 degrees C and 700 degrees C is ca. 20 nm and 50 nm, respectively.

DOI： 10.1246/cl.1999.1175

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

Ultrafine SmFeO(3) powders were prepared by the thermal decomposition at 700 degrees C of the corresponding hexacyanocomplex, Sm[Fe(CN)(6)]. 4H(2)O. These powders were used for the preparation of pastes which were deposited as thick films on alumina substrates with comb-type Au electrodes. The films were fired at different temperatures in the 800-1000 degrees C range. The content of alpha-terpineol, a component of the organic vehicle, was varied in the range 0.0046-4 wt%, The microstructure, the chemical composition at the surface, the electrical conductivity, and the NO(2) sensing properties of the films were investigated. The content of alpha-terpineol strongly influenced the electrical conductivity and its activation energy, A significant reduction in the NO(2) response was observed for the films containing smaller amounts of alpha-terpineol, together with an increase in conductivity. On the other hand, the largest NO(2) response was observed for the films fired at 1000 degrees C when 4 wt% of alpha-terpineol was used. Such increase in conductivity is attributed to a different oxygen surface layer on the SmFeO(3) surface, which is induced by the decomposition reaction of alpha-terpineol during sintering, The materials processing parameters are thus of primary concern for the NO(2) sensing properties of the SmFeO(3) thick films. The correlations found between activation energy, NO(2) sensitivity, and materials characteristics (influenced by the preparation parameters) are reported. These correlations can be used to design the gas-sensing properties of SmFeO(3) thick films for the optimization of their sensing characteristics.

DOI： 10.1111/j.1151-2916.1999.tb02102.x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

Ultrafine SmFeO(3) powders were prepared by the thermal decomposition at 700 degrees C of the corresponding hexacyanocomplex, Sm[Fe(CN)(6)]. 4H(2)O. These powders were used for the preparation of pastes which were deposited as thick films on alumina substrates with comb-type Au electrodes. The films were fired at different temperatures in the 800-1000 degrees C range. The content of alpha-terpineol, a component of the organic vehicle, was varied in the range 0.0046-4 wt%, The microstructure, the chemical composition at the surface, the electrical conductivity, and the NO(2) sensing properties of the films were investigated. The content of alpha-terpineol strongly influenced the electrical conductivity and its activation energy, A significant reduction in the NO(2) response was observed for the films containing smaller amounts of alpha-terpineol, together with an increase in conductivity. On the other hand, the largest NO(2) response was observed for the films fired at 1000 degrees C when 4 wt% of alpha-terpineol was used. Such increase in conductivity is attributed to a different oxygen surface layer on the SmFeO(3) surface, which is induced by the decomposition reaction of alpha-terpineol during sintering, The materials processing parameters are thus of primary concern for the NO(2) sensing properties of the SmFeO(3) thick films. The correlations found between activation energy, NO(2) sensitivity, and materials characteristics (influenced by the preparation parameters) are reported. These correlations can be used to design the gas-sensing properties of SmFeO(3) thick films for the optimization of their sensing characteristics.

DOI： 10.1111/j.1151-2916.1999.tb02102.x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA  

YBa2Cu3O7-delta powders were prepared by the thermal decomposition of a heteronuclear complex, CuY1/3Ba2/3(dhbaen)(NO3)(1/3)(H2O)(3). The products of the complex thermal decomposition were analyzed by TG-DTA, XRD, SEM-Auger and XPS. The decomposition of the CuY1/3Ba2/3-complex was obtained at about 500 degrees C and the product was a mixture of oxides and carbonates. The formation of YBa2Cu3O7-delta proceeded at 800 degrees C, with a gradual decomposition of the carbonates. A homogeneous distribution of each element, Y, Ba and Cu, was observed for the decomposed CuY1/3Ba2/3-complex by SEM-Auger analysis. The binding energy values of Ba-3d5/2 and O1s photolines from Ba and O in the superconductive lattice did not shift during the sputtering period. Furthermore, the formation of Ba rich regions on the surface was depressed by using the complex as a starting material for homogeneous 123-oxide, YBa2Cu3O7-delta. (C) 1999 Elsevier Science S.A. All rights reserved.

DOI： 10.1016/S0925-8388(99)00076-6

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Language：Japanese   Publisher：新居浜工業高等専門学校  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Chemical Society of Japan  

The heteronuclear LaMn(dhbacn)(OH)(NO3)(H2O)4 complex was synthesized and perovskite-type hexagonal LaMnO3 was obtained by its thermal decomposition at 700 °C. Particle size of the samples decomposed at 600 °C and 700 °C is ca. 20 nm and 50 nm, respectively.

DOI： 10.1246/cl.1999.1175

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Language：Japanese   Publisher：社団法人日本セラミックス協会  

NdFe_&lt;0.5&gt;Co_&lt;0.5&gt;O_3, a trimetallic perovskite-type oxide, was prepared by thermal decomposition of a synthesized heteronuclear complex of Nd[Fe_&lt;0.5&gt;Co_&lt;0.5&gt;(CN)_6]・4H_2O. Using XRD, the perovskite-type phase was detected in the sample heated at 500℃ and the complex was completely decomposed to NdFe_&lt;0.5&gt;Co_&lt;0.5&gt;O_3 at 700℃. Distribution of the elements Nd, Fe, and Co on the surface of the complex that decomposed at 800℃ were homogeneous according to Auger electron spectroscopy(AES) analysis. For a solid-state reaction method using a mixture of single oxides(Nd_2O_3, Fe_2O_3 and CoO), a high heating temperature(&gt;1000℃)is needed to form a single phase of the perovskite-type oxide. Fe-rich and Co-rich regions on the surface were clearly detected even in a mixture calcined at 1100℃. Surface concentration and structure of samples obtained by both methods were investigated by X-ray photoelectron spectroscopy(XPS). For both samples, XPS revealed that the(Fe+Co)/Nd ratio was less than unity.

DOI： 10.2109/jcersj.106.958

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NdFe0.5Co0.5O3, a trimetallic perovskite-type oxide, was prepared by thermal decomposition of a synthesized heteronuclear complex of Nd[Fe0.5Co0.5(CN)6]·4H2O. Using XRD, the perovskite-type phase was detected in the sample heated at 500°C and the complex was completely decomposed to NdFe0.5Co0.5O3 at 700°C. Distribution of the elements Nd, Fe, and Co on the surface of the complex that decomposed at 800°C were homogeneous according to Auger electron spectroscopy (AES) analysis. For a solid-state reaction method using a mixture of single oxides (Nd2O3, Fe2O3 and CoO), a high heating temperature ( &gt; 1000°C) is needed to form a single phase of the perovskite-type oxide. Fe-rich and Co-rich regions on the surface were clearly detected even in a mixture calcined at 1000°C. Surface concentration and structure of samples obtained by both methods were investigated by X-ray photoelectron spectroscopy (XPS). For both samples, XPS revealed that the (Fe+Co)/Nd ratio was less than unity.

DOI： 10.2109/jcersj.106.958

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

NdFe0.5C0.5O3, a trimetallic perovskite-type oxide, was prepared by thermal decomposition of a synthesized heteronuclear complex of Nd[Fe0.5Co0.5(CN)6]. 4H(2)O. Using XRD, the perovskite-type phase was detected in the sample heated at 500 degrees C and the complex was completely decomposed to NdFe0.5Co0.5O8 at 700 degrees C. Distribution of the elements Nd, Fe, and Co on the surface of the complex that decomposed at 800 degrees C were homogeneous according to Auger electron spectroscopy (AES) analysis, For a solid-state reaction method using a mixture of single oxides (Nd2O3, Fe2O3 and CoO), a high heating temperature (&gt;1000 degrees C) is needed to form a single phase of the perovskite-type oxide. Fe-rich and Go-rich regions on the surface were clearly detected even in a mixture calcined at 1100 degrees C. Surface concentration and structure of samples obtained by both methods were investigated by X-ray photoelectron spectroscopy (XPS). For both samples, XPS revealed that the (Fe + Co)/Nd ratio was less than unity.

DOI： 10.2109/jcersj.106.958

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELECTROCHEMICAL SOC INC  

A CO2 gas sensor using a combined solid electrolyte of a Na+ conducting Na2O-Al2O3-4SiO(2) glass and an yttria-stabilized zirconia was prepared, and its sensing properties in dry and wet gases were investigated using a variable flow rate of the test gases. The glassy electrolyte in the sensor was suitable as a CO2 sensing material because of its high density and good contact between the electrolytes. In a dry atmosphere, excellent results were obtained for the CO2 gas concentration dependence of the electromotive force (EMF), expressed by EMF (mV) = 547.5 - 74.0 log [C-CO2/ppm] at 470 degrees C in which the sensitivity of 74.0 mV/decade was in fair agreement with the theoretical value based on a two-electron electrochemical reaction. In the case of wet CO2 gas, the sensitivities and response time were depressed even for a high CO2 gas concentration. The decomposition of Na2CO3 into sodium oxide on the Pt electrode was accelerated in the presence of H2O. The reason for the depression of the sensing properties in a humid condition could be ascribed to its reformation reaction as a side reaction.

DOI： 10.1149/1.1838751

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELECTROCHEMICAL SOC INC  

A CO2 gas sensor using a combined solid electrolyte of a Na+ conducting Na2O-Al2O3-4SiO(2) glass and an yttria-stabilized zirconia was prepared, and its sensing properties in dry and wet gases were investigated using a variable flow rate of the test gases. The glassy electrolyte in the sensor was suitable as a CO2 sensing material because of its high density and good contact between the electrolytes. In a dry atmosphere, excellent results were obtained for the CO2 gas concentration dependence of the electromotive force (EMF), expressed by EMF (mV) = 547.5 - 74.0 log [C-CO2/ppm] at 470 degrees C in which the sensitivity of 74.0 mV/decade was in fair agreement with the theoretical value based on a two-electron electrochemical reaction. In the case of wet CO2 gas, the sensitivities and response time were depressed even for a high CO2 gas concentration. The decomposition of Na2CO3 into sodium oxide on the Pt electrode was accelerated in the presence of H2O. The reason for the depression of the sensing properties in a humid condition could be ascribed to its reformation reaction as a side reaction.

DOI： 10.1149/1.1838751

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA  

The thermal decomposition of a heteronuclear complex, La[Fe(CN)(6)]. nH(2)O, leads to the preparation of nanosized perovskite-type LaFeO3 powders. The exothermic decomposition of the cyanide groups at 300 degrees C, starting abruptly and the formation of LaFeO3 without the presence of single oxides such as La2O3 and Fe2O3 were observed. The formation of LaFeO3 from the complex involves the formation of carbonates and nitrates, which facilitate the formation of nanosized LaFeO3 powders. Concomitantly formed carbonate and nitrate decomposed gradually and the specific surface area of nanosized LaFeO3 increased up to 38 m(2) g(-1) at 350 degrees C. (C) 1998 Elsevier Science S.A. All rights reserved.

DOI： 10.1016/S0925-8388(98)00602-1

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA  

The thermal decomposition of a heteronuclear complex, La[Fe(CN)(6)]. nH(2)O, leads to the preparation of nanosized perovskite-type LaFeO3 powders. The exothermic decomposition of the cyanide groups at 300 degrees C, starting abruptly and the formation of LaFeO3 without the presence of single oxides such as La2O3 and Fe2O3 were observed. The formation of LaFeO3 from the complex involves the formation of carbonates and nitrates, which facilitate the formation of nanosized LaFeO3 powders. Concomitantly formed carbonate and nitrate decomposed gradually and the specific surface area of nanosized LaFeO3 increased up to 38 m(2) g(-1) at 350 degrees C. (C) 1998 Elsevier Science S.A. All rights reserved.

DOI： 10.1016/S0925-8388(98)00602-1

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Language：Japanese   Publisher：The Ceramic Society of Japan  

PbX_2-PbO-SiO_2(X=Cl, Br and I)glasses were prepared and their electrical properties were investigated. The sole carrier for these glasses is the X^- ion, which was estimated from the EMF(electromotive force)of the X_2 gas concentration cell and the electrical properties. The ionic conductivity was enhanced with a decrease in ionic radius and increase in content of the X^- ion the glasses. The conductivities for the glass plates are about one order of magnitude higher than those for the pellets prepared from glass powder. For the X=I system, a maximum conductivity of 4.5×10^<-7> S・cm^<-1> at 373 K was obtained for the composition 0.59PbI_2・0.31PbO・0.10SiO_2. The glass formation region was determined for the PbI_2-PbO-SiO_2 system.

DOI： 10.2109/jcersj.106.645

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Other Link： https://jlc.jst.go.jp/DN/JALC/00370921974?from=CiNii

PbX2-PbO-SiO2 (X=Cl, Br and I) glasses were prepared and their electrical properties were investigated. The sole carrier for these glasses is the X- ion, which was estimated from the EMF (electromotive force) of the X2 gas concentration cell and the electrical properties. The ionic conductivity was enhanced with a decrease in ionic radius and increase in content of the X- ion in the glasses. The conductivities for the glass plates are about one order of magnitude higher than those for the pellets prepared from glass powder. For the X=I system, a maximum conductivity of 4.5 × 10-7 S·cm-1 at 373 K was obtained for the composition 0.59PbI2·0.31PbO·0.10SiO2. The glass formation region was determined for the PbI2-PbO-SiO2 system.

DOI： 10.2109/jcersj.106.645

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

PbX2-PbO-SiO2 (X=Cl, Br and I) glasses were prepared and their electrical properties were investigated. The sole carrier for these glasses is the X- ion, which was estimated from the EMF (electromotive force) of the X-2 gas concentration cell and the electrical properties. The ionic conductivity was enhanced with a decrease in ionic radius and increase in content of the X- ion in the glasses. The conductivities for the glass plates are about one order of magnitude higher than those for the pellets prepared from glass powder. For the X=I system, a maximum conductivity of 4.5 x 10(-7) S cm(-1) at 373 K was obtained for the composition 0.59PbI(2) 0.31PbO 0.10SiO(2). The glass formation region was determined for the PbI2-PbO-SiO2 system.

DOI： 10.2109/jcersj.106.645

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Heteronuclear complexes Ln[FexCo1-x(CN)(6)]4H(2)O (Ln = Pr-Yb) were synthesized and the crystal structures of thermally decomposed complexes were investigated. For Ln = Pr-Gd, only perovskite-type oxides (crystal system: orthorhombic) were formed even when the complexes decomposed at 800 degrees C. The lattice constants (a, b and c) of the oxides increased linearly with increasing Fe/Co ratio. On the other hand, for Ln = Dy-Yb, the Ln(2)O(3) phase was obtained as the major product, especially for lower Fe content. The single phase of the perovskite-type oxide could not be obtained even for x = 1, although the diffraction peaks due to the perovskite structure gradually increased with increasing Fe content. (C) 1998 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0167-2738(98)00015-0

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Language：Japanese   Publishing type：Research paper (other academic)  

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Language：Japanese   Publisher：新居浜工業高等専門学校  

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：WORLD PUBLISHING CORPORATION  

High-conductivity and high-density samples in the NASICON-type electrolyte series, i.e., the Na(3)Z(2-(x/4))Si2-xP1+xO12 system, with x = 0(A), 0.667(B), and 1.333(C) were synthesized using a sol-gel process. The sinterability was improved with increasing the x value, but the conductivity decreased. The CO2 gas sensors using the highly dense B and C samples show good EMF response which is very close to the theoretical value.

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：AMER CERAMIC SOC  

Powders and pellets of new NASICON compositions have been synthesized using a mixed inorganic-organic sol-gel synthesis, by the preliminary formation of a pre-hydrolized TEOS xerogel. The investigated compositions can be described by the general formula Na3Zr2-(x/4)Si2-xP1+xO12 obtained by keeping constant (= 3) the Na concentration at the optimum value reported for ionic conductivity, with x = 0 (the usual NASICON composition), 0.667, and 1.333. The xerogels were calcined at various temperatures in the range 400-800 degrees C. The samples were analyzed by TG/DTA, BET measurements, XRD, EDS, and SEM. The powders were sintered into pellets at 1100 degrees C. The sinterability increased with increasing the x value. This is attributed to the presence of a glassy phase and the occurrence of liquid phase sintering. The electrical conductivity of the NASICON sintered bodies, measured by a.c. impedance spectroscopy, is correlated with the lattice parameters of the hexagonal structure, and increased with increasing the x value.

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Language：Japanese   Publisher：日本海水学会  

DOI： 10.11457/swsj1965.52.41

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Language：Japanese   Publisher：日本海水学会  

DOI： 10.11457/swsj1965.51.395

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Language：English   Publisher：社団法人日本セラミックス協会  

Heteronuclear complexes of Ln[Fe_xCo_&lt;1-x&gt;(CN)_6]・4H_2O (Ln=Pr-Yb) were synthesized and their thermal decomposition products were investigated. Thermal decomposition of the complexes results in the formation of perovskite-type oxides for Ln=Pr-Gd even at 800℃. The lattice parameters, a-, b- and c-lattice constants (crystal system: orthorhombic) increase linearly with the ratio of Fe/Co for the perovskite-type oxide. For Ln=Dy through Yb, the Ln_2O_3 phase is observed as the major product for x=0, but its content decreased with an increase in the Fe content; however, a single phase of the perovskite-type oxide was not formed for x=1. The perovskite-type structure for the Fe systems is easier to form compared with the Co systems. We clarified that the formation of the perovskite-type oxide is mainly affected by the ionic radius of the Ln^&lt;3+&gt; ion and the T^&lt;3+&gt; ion (T=Fe or Co).

DOI： 10.2109/jcersj.105.963

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Heteronuclear complexes of Ln[FexCo1-x(CN)6]·4H 2O(Ln=Pr-Yb) were synthesized and their thermal decomposition products were investigated. Thermal decomposition of the complexes results in the formation of perovskite-type oxides for Ln=Pr-Gd even at 800°C. The lattice parameters, a-, b- and c-lattice constants (crystal system: orthorhombic) increase linearly with the ratio of Fe/Co for the perovskite-type oxide. For Ln=Dy through Yb, the Ln2O3 phase is observed as the major product for x=0, but its content decreased with an increase in the Fe content; however, a single phase of the perovskite-type oxide was not formed for x=1. The perovskite-type structure for the Fe systems is easier to form compared with the Co systems. We clarified that the formation of the perovskite-type oxide is mainly affected by the ionic radius of the Ln3+ ion and the T3+ ion (T = Fe or Co).

DOI： 10.2109/jcersj.105.963

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Heteronuclear complexes of Ln[FexCo1-x(CN)(6)].4H(2)O(Ln=PT-Yb) were synthesized and their thermal decomposition products were investigated. Thermal decomposition of the complexes results in the formation of perovskite-type oxides for Ln=Pr-Gd even at 800 degrees C. The lattice parameters, a-, b-and c-lattice constants (crystal system: orthorhombic) increase linearly with the ratio of Fe/Co for the perovskite-type oxide. For Ln=Dy through Yb, the Ln(2)O(3) phase is observed as the major product for x=0, but its content decreased with an increase in the Fe content; however, a single phase of the perovskite-type oxide was not formed for x=1. The perovskite-type structure for the Fe systems is easier to form compared with the Co systems. We clarified that the formation of the perovskite-type oxide is mainly affected by the ionic radius of the Ln(3+) ion and the T3+ ion (T=Fe or Co).

DOI： 10.2109/jcersj.105.963

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA LAUSANNE  

To facilitate the preparation of finer and more homogeneous CuREOx and to achieve a lowering of the formation temperature, heteronuclear CuRE(1:1) complexes, CuRE(dhbaen)(NO3). nH(2)O were synthesized as precursor. As it was expected for RE=La through Gd, only a mixture of CuO and CuRE2O4 was formed even when the complex decomposed at 800 degrees C since the Cu/RE ratio is 1. For RE=Y and Tb through Lu, Cu2RE2O5 was formed by way of CuO and RE2O3. The structure of the decomposed product is controlled by the coordination number and ionic size of RE ion. The minimum radius ratio for eightfold coordination of RE3+ ion suggests that preparation of homogeneous Cu:RE(1:1) oxide with Cu2Ho2O5 type structure is difficult for RE=La through Gd. (C) 1997 Elsevier Science S.A.

DOI： 10.1016/S0925-8388(97)00144-8

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA LAUSANNE  

To facilitate the preparation of finer and more homogeneous CuREOx and to achieve a lowering of the formation temperature, heteronuclear CuRE(1:1) complexes, CuRE(dhbaen)(NO3). nH(2)O were synthesized as precursor. As it was expected for RE=La through Gd, only a mixture of CuO and CuRE2O4 was formed even when the complex decomposed at 800 degrees C since the Cu/RE ratio is 1. For RE=Y and Tb through Lu, Cu2RE2O5 was formed by way of CuO and RE2O3. The structure of the decomposed product is controlled by the coordination number and ionic size of RE ion. The minimum radius ratio for eightfold coordination of RE3+ ion suggests that preparation of homogeneous Cu:RE(1:1) oxide with Cu2Ho2O5 type structure is difficult for RE=La through Gd. (C) 1997 Elsevier Science S.A.

DOI： 10.1016/S0925-8388(97)00144-8

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Language：Japanese   Publishing type：Research paper (other academic)  

DOI： 10.11457/swsj1965.51.395

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE SA LAUSANNE  

The effects of BaO contamination on the behaviour of a Cl-2 gas sensor using a 0.97BaCl(2)-0.03KCl solid electrolyte have been investigated. The addition of BaO to the electrolyte is found to produce unfavourable effects on both the measuring and reference electrodes through a side reaction such as BaO + Cl-2 --&gt; BaCl2 + (1/2)O-2. The presence of BaO in the vicinity of the measuring electrode results in decreases in the e.m.f. and rate of response, especially when the Cl-2 gas concentration is lowered to a few tens of ppm. Its presence near to the reference electrode, on the other hand, results in the upward deviation of the e.m.f. over the entire range of Cl-2 concentration. The probe prepared in vacuo, free of such BaO contamination, gives e.m.f. values in good agreement with the theoretical ones for Cl-2 gas concentrations between 10 and 1000 ppm, In contrast, the probe prepared in air shows a slower response as well as a more extensive deviation from theory in the low Cl-2 concentration range, suggesting that the electrolyte near the measuring electrode is contaminated with BaO.

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A glassy solid electrolyte of the (1-x)PbI2-xPbO system was prepared using two kinds of quenching methods. In the case of the iron pressing method, 0.68PbI2-0.32PbO (x=0.32) glass was obtained when PbI2 melt reacts with oxygen in air. In the case of the quenching method using ice water, the glassy sample was not obtained when x&lt;0.35. Conductivity was enhanced and crystallization temperature was decreased with decreasing PbO content x. A maximum conductivity of 6.2 × 10-7 S·cm-1 at 373 K was obtained for x=0.32 glass plate prepared by the iron pressing method. This value is almost equal to the maximum conductivity of anion conducting glasses reported. I- ions would be the sole carrier ions, based on an estimation of the electromotive force of the I2 concentration cell.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CERAMIC SOC  

Sodium-rich NASICON-type ceramics, the NaM(2)(PO4)(3) + yNa(2)O (M = Ge, Ti, Hf, Zr) systems, were investigated in order to obtain a material having a high Na+ conductivity and high density, The ionic conductivity and the sinterability were greatly improved by an increase in the value off for all of the systems examined. Added Na2O was not soluble in the NASICON-type skeleton, since the lattice constants and the X-ray diffraction patterns were not changed by the Na2O addition in all of the samples, Na2O acts as a flux for obtaining highly dense ceramics and highly conductive grain boundaries. Partial A(2) site insertion by Na+ ions is effective for the enhancement of conductivity, because the conductivity for Na(1.5)M(III)(0.5)Zr-1.5(PO4)(3) (M = In or Y) is about 1 order of magnitude higher than the maximum conductivity of the NaZr2(PO4)(3) + yNa(2)O system.

DOI： 10.1111/j.1151-2916.1996.tb09052.x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CERAMIC SOC  

Sodium-rich NASICON-type ceramics, the NaM(2)(PO4)(3) + yNa(2)O (M = Ge, Ti, Hf, Zr) systems, were investigated in order to obtain a material having a high Na+ conductivity and high density, The ionic conductivity and the sinterability were greatly improved by an increase in the value off for all of the systems examined. Added Na2O was not soluble in the NASICON-type skeleton, since the lattice constants and the X-ray diffraction patterns were not changed by the Na2O addition in all of the samples, Na2O acts as a flux for obtaining highly dense ceramics and highly conductive grain boundaries. Partial A(2) site insertion by Na+ ions is effective for the enhancement of conductivity, because the conductivity for Na(1.5)M(III)(0.5)Zr-1.5(PO4)(3) (M = In or Y) is about 1 order of magnitude higher than the maximum conductivity of the NaZr2(PO4)(3) + yNa(2)O system.

DOI： 10.1111/j.1151-2916.1996.tb09052.x

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Language：Japanese   Publisher：社団法人日本セラミックス協会  

A glassy solid electrolyte of the(1-x)PbI_2-xPbO system was prepared using two kinds of quenching methods. In the case of the iron pressing method, 0.68PbI_2-0.32PbO(x=0.32)glass was obtained when PbI_2 melt reacts with oxygen in air. In the case of the quenching method using ice water, the glassy sample was not obtained when x&lt;0.35. Conductivity was enhanced and crystallization temperature was decreased with decreasing PbO content x. A maximum conductivity of 6.2×10^&lt;-7&gt; S・cm^&lt;-1&gt; at 373 K was obtained for x=0.32 glass plate prepared by the iron pressing method. This value is almost equal to the maximum conductivity of anion conducting glasses reported. I^- ions would be the sole carrier ions, based on an estimation of the electromotive force of the I_2 concentration cell.

DOI： 10.2109/jcersj.104.235

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

A glassy solid electrolyte of the (1-x)PbI2-xPbO system was prepared using two kinds of quenching methods. In the case of the iron pressing method, 0.68PbI(2)-0.32PbO (x=0.32) glass was obtained when PbI2 melt reacts with oxygen in air. In the case of the quenching method using ice water, the glassy sample was not obtained when x&lt;0.35. Conductivity was enhanced and crystallization temperature was decreased with decreasing PbO content x. A maximum conductivity of 6.2 x 10(-7) S . cm(-1) at 373 K was obtained for x=0.32 glass plate prepared by the iron pressing method. This value is almost equal to the maximum conductivity of anion conducting glasses reported, I- ions would be the sole carrier ions, based on an estimation of the electromotive force of the I-2 concentration cell.

DOI： 10.2109/jcersj.104.235

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

The all-solid, lithium rechargeable battery, which if available would find many applications, is one reason for carrying out research into Li+-conducting solids. Fast Li+-conducting ceramic electrolytes are reviewed with regard to their electrical properties and crystal structure. Both non-oxide based ceramics and oxide materials are considered, and possibilities for further developments-e.g., the preparation of the electrolyte by thin him techniques-are pointed out.

DOI： 10.1002/adma.19960080205

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Language：English   Publisher：WILEY-V C H VERLAG GMBH  

The all-solid, lithium rechargeable battery, which if available would find many applications, is one reason for carrying out research into Li+-conducting solids. Fast Li+-conducting ceramic electrolytes are reviewed with regard to their electrical properties and crystal structure. Both non-oxide based ceramics and oxide materials are considered, and possibilities for further developments-e.g., the preparation of the electrolyte by thin him techniques-are pointed out.

DOI： 10.1002/adma.19960080205

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

A Cl-2 gas sensor with a 0.97PbCl(2)-0.03KCl solid electrolyte and a Pb reference electrode was prepared by a melting method using an evacuated closed tube. The electromotive force (EMF) measured at 573 K agreed with the calculated value for Cl-2 gas concentrations from 10 ppm to 1000 ppm. The response time was long when the operating temperature is lower than 473 K.

DOI： 10.1246/cl.1996.689

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

A Cl-2 gas sensor with a 0.97PbCl(2)-0.03KCl solid electrolyte and a Pb reference electrode was prepared by a melting method using an evacuated closed tube. The electromotive force (EMF) measured at 573 K agreed with the calculated value for Cl-2 gas concentrations from 10 ppm to 1000 ppm. The response time was long when the operating temperature is lower than 473 K.

DOI： 10.1246/cl.1996.689

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Royal Society of Chemistry (RSC)  

Ionic conductivities have been investigated for lanthanoid silicates of the Ln10(SiO4)6O3 solid solution series and related compounds. The activation energy and conductivity at 500°C were estimated to be 69 kJ mol-1 and 1.8 x10-4 S cm -1 for La10(SiO4)6O3 and 71 kJ mol-1 and 1.5x10-4S cm 1 for Nd 10(SiO4)6O3. The a and c lattice constants of the hexagonal phase decreased with decreasing radius of the Ln 3+ ion for Ln10(SiO4)6O3 (Ln=La, Nd, Sm, Gd and Dy). The activation energy increased and the conductivity decreased when Ln3+ ions with smaller ionic radii were used. The sole carrier in these materials is the O2- ion.

DOI： 10.1039/jm9950501801

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

Ionic conductivities have been investigated for lanthanoid silicates of the Ln(10)(SiO4)(6)O-3 solid solution series and related compounds. The activation energy and conductivity at 500 degrees C were estimated to be 69 kJ mol(-1) and 1.8 x 10(-4) S cm(-1) for La-10(SiO4)(6)O-3 and 71 kJ mol(-1) and 1.5 x 10(-4) S cm(-1) for Nd-10(SiO4)(6)O-3. The a and c lattice constants of the hexagonal phase decreased with decreasing radius of the Ln(3+) ion for Ln(10)(SiO4)(6)O-3 (Ln = La, Nd, Sm, Gd and Dy). The activation energy increased and the conductivity decreased when Ln(3+) ions with smaller ionic radii were used. The sole carrier in these materials is the O2- ion.

DOI： 10.1039/jm9950501801

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

Electrical properties were investigated for lanthanoid- silicates of Ln(10)(SiO4)(6)O-3 (Ln=La, Nd, Sm, Gd and Nd). The conductivity at 773 K was 2.3 X 10(4) S cm(-1) for Nd-10(SiO4)(6)O-3. The sole carrier is the O2- ion, which was determined using an O-2 gas concentration cell.

DOI： 10.1246/cl.1995.431

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

The electrical conductivity of (1 - x)PbBr2 . xKBr solid electrolytes is enhanced on increasing x to x = 0.02. The maximum conductivity, 2.7 x 10(-6) S . cm(-1) at 298 K was obtained for x = 0.02. The transference number for the Br- ion is almost equal to 1, which was determined by the Tubandt's method, dc conductivity with Au electrodes, and the electromotive force of a Br-2 gas concentration cell. The Ba-based system, (1 - x)BaBr2 . xKBr solid electrolyte, has a lower conductivity compared with that for the Pb-based system.

DOI： 10.1021/cm00054a025

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

The electrical conductivity of (1-x)PbBr2 . xKBr solid electrolytes enhanced with increasing x up to x=0.02, where 2.7X10(-6) S . cm(-1) at 298 K was obtained. The carrier ion for this system was Bi, as determined by the Tubandt's method.

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Language：English   Publishing type：Research paper (scientific journal)  

The electrical conductivity of (1 - x)PbBr2•xKBr solid electrolytes is enhanced on increasing x to x = 0.02. The maximum conductivity, 2.7 x 10-6 S•cm-1 at 298 K was obtained for x = 0.02. The transference number for the Br- ion is almost equal to 1, which was determined by the Tubandt's method, dc conductivity with Au electrodes, and the electromotive force of a Br2 gas concentration cell. The Ba-based system, (1 - x)BaBr2•xKBr solid electrolyte, has a lower conductivity compared with that for the Pb-based system. © 1995, American Chemical Society. All rights reserved.

DOI： 10.1021/cm00054a025

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

DOI： 10.1021/ar00045a002

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Language：English   Publisher：AMER CHEMICAL SOC  

DOI： 10.1021/ar00045a002

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

The electrical properties were studied for the (1-y)Li3Cr2(PO4)3-yLi5Mg2(PO4)3 system. The Mg2+ ion can not replace the Cr3+ site. The crystal structure for Li3Cr2(PO4)3 in this system is the beta-Fe2(SO4)3 type monoclinic phase. The conductivity and the sinterability improve with the increase in y for the phosphate system. The maximum conductivity was 4.6x10(-5) S.cm-1 at 298 K for y=0.2. The activation energy for a Li+ ion migration at the bulk component was ca. 0.43 eV for all the samples.

DOI： 10.1246/cl.1993.2033

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELECTROCHEMICAL SOC INC  

A Cl2 gas sensor using BaCl2-KCl solid electrolyte was investigated. The conductivity was greatly enhanced by KCl doping of the (1 - x) BaCl2-xKCl system, and a maximum conductivity of 5.6 x 10(-5) S . cm-1 at 573 K was obtained for x = 0.02. The sensor probe was prepared by a melting method at 1373 K. The electromotive force (EMF) measurement with the Cl2 gas sensor using the 0.97BaCl2-0.03KCl solid electrolyte was performed with an Ag-AgCl solid reference electrode and an RUO2 measuring electrode. Good agreement between the measured and the calculated EMF values was obtained for Cl2 gas concentrations from 50 to 10,000 ppm at 623 K. The EMF response time with a change in Cl2 concentration is ca. 1 min for above 100 ppm and 2 to 5 min for lower concentrations. The measured EMF was not influenced by O2 or CO2 gas concentration. This sensor probe was very stable in the presence of water vapor at 623 K during a 90 day test period.

DOI： 10.1149/1.2221010

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

The electrical properties and the crystal structure were investigated for the ceramic electrolytes based on LiHf2(PO4)3. The conductivity enhanced by the Li2O addition with LiHf2(PO4)3 system and by the increase of x for Li1+xMxHf2-x(PO4)3 (M = Cr, Fe, Sc, In, Lu or Y) systems. The P2(1)/n monoclinic phase transformed to NASICON-type R3cBAR rhombohedral phase at above 1173 K. The activation energy for Li+ ion migration was decreased by the phase transition. The activation energy for bulk component was 0.42 eV for the NASICON-type structure. A maximum conductivity at 298 K is 1.7 x 10(-4) S.cm-1 for the sample of Li1.2Fe0.2Hf1.8(PO4)3.

DOI： 10.1016/0167-2738(93)90387-I

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELECTROCHEMICAL SOC INC  

The electrical properties of systems of LiMxTi2-x(PO4)3+yLi2O, M = Ge, Sn, Hf, and Zr, were examined in detail. The conductivity and the sinterability increased with the amount of excess lithium oxide in the phosphate. The secondary Li2O phase acts as a flux to accelerate the sintering process and to obtain high conductivity grain boundaries. The conductivity decreased and the activation energy of the bulk component for Li+ migration increased by the partial substitution of Ti4+ for M4+ in systems of LiMxTi2-x(PO4)3+0.2Li2O, M = Ge, Sn, Hf, and Zr. A minimum activation energy of 0.28-0.30 eV, was obtained for the sample with ca. 1310 angstrom3 in the cell volume. LiTi2(PO4)3 has the most suitable tunnel size for a Li+ migration through the NASICON-type network structure.

DOI： 10.1149/1.2220723

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

The Cl2 gas sensor using 0.97BaCl2-0.03KCl solid electrolyte and an Ag metal reference electrode was prepared by a melting method. The melting method has the advantage of ease for the sensor preparation. The sensor probe obtained has a high mechanical strength. The measured EMF agreed with the calculated one for Cl2 gas concentrations from 50 ppm to 10000 ppm.

DOI： 10.1246/cl.1993.1039

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Language：Japanese   Publishing type：Research paper (other academic)  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

The electrical properties and sinterability were studied for Li1+xMxGe2-x(PO4)3, M=Al3+, Cr3+, Ga3+, Fe3+, Sc3+, and In3+ systems. Due to the closer ionic radius of Al3+ and Cr3+ Compared to that of Ge4+, those M3+ ions easily substitute the Ge4+ site. Larger cations, such as Ga3+, Fe3+, SC3+, and In3+, were difficult to substitute the Ge4+ site. The ionic conductivity and sinterability improved with an increase in x for all of the M3+-substituted systems. In particular, an Al3+- or Cr3+-substituted system shows higher conductivity; the maximum conductivity is 2.4X10(-4) S cm-1 at 298 K for Li1.5Al0.5Ge1.5(PO4)3. The enhancement in the conductivity is attributed to a decrease in the porosity and a lowering of the activation energy in the grain boundaries. The activation energy for Li+ ion conduction of the bulk component was 0.38 eV for Li1+xMxGe2-x(PO4)3 electrolytes, and was almost independent of M3+ substitution.

DOI： 10.1246/bcsj.65.2200

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Language：Japanese   Publisher：日本セラミックス協会  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

The ionic conductivity of a solid electrolyte, Li1.3Al0.3Ti1.7 (PO4)3, was measured with Li and Li-Al alloy electrodes. The contact resistance between the Li electrode and the electrolyte was a dominant factor for the DC conductivity. A higher DC conductivity was obtained by an utilization of the Li4Al alloy electrodes.

DOI： 10.1246/cl.1991.1567

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

A lithium salt (Li3PO4 or Li3BO3) was added to LiTi2(PO4)3 to obtain a dense pellet of the phosphate. The porosity of the sintered pellets decreased and the conductivity was enhanced by the utilization of a binder. A maximum conductivity of 3.0 x 10(-4) S.cm-1 at 298 K was obtained for a sample of LiTi2(PO4)3-0.2Li3BO3. The activation energy for the lithium migration at grain boundaries was decreased by the addition of lithium salt. The reason for the conductivity enhancement was attributed to a decrease in the activation energy for the lithium migration at the grain boundary and an increase in the contact area between grains. The conductivity of the bulk component was also increased by the enhancement of Li+-ion migration at grain boundaries.

DOI： 10.1016/0167-2738(91)90247-9

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Language：English   Publishing type：Research paper (scientific journal)  

A lithium salt (Li3PO4 or Li3BO3) was added to LiTi2(PO4)3 to obtain a dense pellet of the phosphate. The porosity of the sintered pellets decreased and the conductivity was enhanced by the utilization of a binder. A maximum conductivity of 3.0 × 10-4 S·cm-1 at 298 K was obtained for a sample of LiTi2(PO4)3-0.2Li3BO3. The activation energy for the lithium migration at grain boundaries was decreased by the addition of lithium salt. The reason for the conductivity enhancement was attributed to a decrease in the activation energy for the lithium migration at the grain boundary and an increase in the contact area between grains. The conductivity of the bulk component was also increased by the enhancement of Li+-ion migration at grain boundaries. © 1991.

DOI： 10.1016/0167-2738(91)90247-9

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DOI： 10.2473/shigentosozai.107.899

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Language：Japanese   Publisher：The Mining and Materials Processing Institute of Japan  

The present study was undertaken to investigate the practical use of SO&lt;SUB&gt;2&lt;/SUB&gt; gas sensor employing β″-alumina solid electrolyte in the field of industry. In the cell with β″-alumina solid electrolyte, the use of (β″+β″)-alumina coexistent mixture in air as a solid reference electrode lead to a simple structure of the SO&lt;SUB&gt;2&lt;/SUB&gt; gas sensor. In this paper we reported the practical application of SO&lt;SUB&gt;2&lt;/SUB&gt; gas sensor with the following cell in copper smelting plants.&lt;BR&gt;Pt, (β+β″)-alumina in air/β″-alumina/S0&lt;SUB&gt;2&lt;/SUB&gt;+O&lt;SUB&gt;2&lt;/SUB&gt;+SO&lt;SUB&gt;3&lt;/SUB&gt;, Pt&lt;BR&gt;From the present experiments the following conclusions were obtained.&lt;BR&gt;1) The present experimental cell showed a satisfactory response and the data agreed very closely with those obtained by another analytical method (non-dispersive infrared rays).&lt;BR&gt;2) In a long period of measuring, the emf&#039;s of this sensor varied with the lapse of time. However it was confirmed that its reproducibility is obtained by the correction of the calibration curve once a few days.

DOI： 10.2473/shigentosozai.107.899

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

DOI： 10.1246/cl.1990.1825

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELECTROCHEMICAL SOC INC  

DOI： 10.1149/1.2086597

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

DOI： 10.1246/cl.1990.331

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Language：English   Publishing type：Research paper (scientific journal)  

Lithium titanium phosphates mixed with various metal ions of M3+ (M=Al, Cr, Ga, Fe, Sc, In, Lu, Y, or La), Li1+xMxTi2-x(PO4)3 systems, were prepared, and their properties were investigated. The conductiv ity was enhanced and the porosity of the sintered pellets decreased by the partial replacement of Ti4+ with the M3+ ion. The porosity was considerably influenced by the ionic radius of the M3+ ion. The sinterability was greatly related to the increase of lithium concentrations at the grain boundary. The conductivity enhancement by the substitution mainly resulted from the densification of the sintered pellets. © 1990.

DOI： 10.1016/0167-2738(90)90282-V

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Language：Japanese   Publisher：化学同人  

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1149/1.2096693

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Publishing type：Research paper (scientific journal)   Publisher：The Electrochemical Society  

DOI： 10.1149/1.2096693

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Other Link： https://iopscience.iop.org/article/10.1149/1.2096693/pdf

Language：Japanese   Publisher：新居浜工業高等専門学校  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHAPMAN HALL LTD  

DOI： 10.1007/BF01161478

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