記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：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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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：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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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：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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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：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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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：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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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：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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記述言語：英語   掲載種別：研究論文（学術雑誌）  

© 2016, Tsinghua University Press and Springer-Verlag Gmbh.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 °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 °C. The heat generation ability and the hysteresis loss value were proportional to the cube of the magnetic field (H3). The heat generation ability (W·g−1) of the Y3Fe5O12–0.3SiC sample calcined at 1250 °C could be expressed by the equation 4.5×10−4 · f · H3 using the frequency f (kHz) and the magnetic field H (kA·m−1).

DOI： 10.1007/s40145-016-0198-9

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：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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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：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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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：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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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：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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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：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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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：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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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：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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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Bilayer Ni-YSZ anode films for SOFCs were prepared by electrophoretic deposition (EPD). The thickness of each layer of the bilayer anode films, which consist of 50 wt% Ni-YSZ as the active layer and 70 wt% Ni-YSZ as the current collecting layer (50Ni-YSZ/70Ni-YSZ), were controlled by the deposition time of the EPD process. For the monolayer anodes, 70Ni-YSZ showed a better performance than 50Ni-YSZ. The bilayer film, 50Ni-YSZ/70Ni-YSZ, showed an even better performance than the 70Ni-YSZ monolayer film. Probably, 50Ni-YSZ anode has more reaction sites compared to 70Ni-YSZ; on the other hand, 70Ni-YSZ has higher porosity to be a gas diffusion (or current collecting) layer. The anodic performance of the bilayer film significantly depended on the film thickness of the 50Ni-YSZ layer, and 3 mu m was found to be the optimized thickness as the active layer, which suggests that the charge transfer reaction site extended up to a 3-mu m thickness from the anode/electrolyte interface. (C) 2015 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.123.235

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：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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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：Electrochemical Society Inc.  

Bimetallic Ni&lt
inf&gt
1-x&lt
/inf&gt
Fe&lt
inf&gt
x&lt
/inf&gt
/SDC powders containing 20wt% Ni-Fe were prepared and their anodic properties for SOFC were evaluated. The impedance spectra of the Ni&lt
inf&gt
1-x&lt
/inf&gt
Fe&lt
inf&gt
x&lt
/inf&gt
/SDC anodes at 800°C consisted of the ohmic component, R&lt
inf&gt
ohmic&lt
/inf&gt
, and depressed arcs, R&lt
inf&gt
HF&lt
/inf&gt
and R&lt
inf&gt
LF&lt
/inf&gt
. The R&lt
inf&gt
ohmic&lt
/inf&gt
component was due to the solid electrolyte layer, (ScO&lt
inf&gt
1.5&lt
/inf&gt
)&lt
inf&gt
0.18&lt
/inf&gt
(CeO&lt
inf&gt
2&lt
/inf&gt
)&lt
inf&gt
0.01&lt
/inf&gt
(ZrO&lt
inf&gt
2&lt
/inf&gt
)&lt
inf&gt
0.81&lt
/inf&gt
. The R&lt
inf&gt
HF&lt
/inf&gt
component was significantly reduced by the Fe addition, but apparent dependence was not observed for the R&lt
inf&gt
LF&lt
/inf&gt
component. The x=0.5 composition possessed the small R&lt
inf&gt
HF&lt
/inf&gt
and R&lt
inf&gt
LF&lt
/inf&gt
values. Accordingly, the single cell performance at 800°C was the maximum at x=0.5, and that was in the order of x=0.5 ≈ 0.2 &gt
0.8 ≈ 0 &gt
1.0. The mean crystallite size of Ni-Fe alloy increased approximately in this order. Therefore, we concluded that Fe addition to Ni decreases the particle size of Ni-Fe alloy, resulting in the enhancement of the catalytic activity of Ni&lt
inf&gt
1-x&lt
/inf&gt
Fe&lt
inf&gt
x&lt
/inf&gt
/SDC anode.

DOI： 10.1149/06801.1427ecst

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE SA  

A perovskite-type SmFeO3 oxide, which has a p-type semiconducting feature, was used as a chemo-resistive sensor material for VOC detection. SmFeO3 particles were deposited on a comb-type Pt electrode printed on an alumina substrate. In this study, 15 kinds of VOCs (methanol, ethanol, propanol, butanol, acetic acid, propionic acid, methyl acetate, ethyl acetate, acetone, methylethylketone, benzene, toluene, xylene, ethyl benzene, and chlorobenzene) with concentrations below 10 ppm were examined in the range of 350 and 500 degrees C. The resistance of the sensor increased when the referenced air was contaminated with the VOCs. The sensing behavior was characterized by the relationship, R-voc/R-air = 1 + alpha C-1/m. The observed results suggested the detecting ability of ppb-levels of several VOCs. (C) 2014 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.snb.2014.06.031

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

Ni-impregnated SDC powders were prepared as a SOFC anode material. Surface area of the SDC powders was regulated with pre-calcination temperature and it was ranging from 12 to 93 m(2)/g. The averaged Ni particle size on SDC was fairly affected with surface area of the SDC supports. The smallest Ni particle size obtained in this study was 48 nm when the surface area of SDC was 27 m(2)/g. By further increasing the surface area of SDC to 93 m(2)/g, Ni particle size was adversely enlarged. The maximum power density increased with decreasing the averaged Ni particle size of Ni/SDC anode. The maximum power densities were 39.5 mWcm(-2) for dry H-2 and 106.5 mWcm(-2) for dry CH4. (C) 2014 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.ssi.2014.02.012

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE SA  

A potentiometric gas sensor with a planar-type structure was fabricated and used to detect some offensive odorants in harsh environments such as ammonia, trimethyl-amine, methyl mercaptan and hydrogen sulfide. The electrode potential of the planar type sensor with a (Au/YSZ)vertical bar YSZ vertical bar(Pt/YSZ) structure responded to such compounds at sub-ppm levels. The sensitivity at 450 C was in the order of methyl mercaptan &gt; hydrogen sulfide &gt; ammonia &gt; trimethylamine. (C) 2013 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.snb.2013.10.005

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：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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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：Materials Research Society  

Both Ni and alkaline earth metal oxide (MO: CaO, SrO, and BaO)-impregnated SDC powders were prepared as an SOFC anode material. The averaged Ni particle size on SDC was affected by the kind of alkaline earth metal oxide added. The addition of SrO and BaO to Ni/SDC anode enhanced power densities of both H2-SOFC and CH4-SOFC and the addition of CaO lowered them. The maximum power density increased with decreasing the averaged Ni particle size of Ni-MO/SDC anode.

DOI： 10.1557/opl.2014.815

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

Bi-layered cathodes with the LSM/LSM-YSZ structure for solid oxide fuel cells were successfully formed on the carbon-sputtered surface of a YSZ sheet by electrophoretic deposition (EPD). The thicknesses of the first layer of LSM-YSZ (LY) and the second layer of La0.8Sr0.2MnO3 (LSM) could be controlled by adjusting the deposition time in the EPD process. The cathodic properties of the bi-layered structures were superior to those of the mono-layered structures, and were dependent on the thickness of each layer. Decreasing the thickness of the first layer and increasing that of the second layer tended to reduce both polarization and ohmic resistances. The optimal thickness of the first layer at the operating temperature of 600 degrees C was 4 mu m, suggesting that an effective three-phase boundary was extended from the interface between the electrolyte and cathode film to around 4 mu m thickness. (C) 2012 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jpowsour.2012.04.079

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE SA  

Fine particles of perovskite-type SmFe1-xCoxO3 oxides were synthesized by the thermal decomposition of the corresponding heteronuclear hexacyano complexes. The sensing characteristics of ozone, methylethylketone (MEK), ethanol and benzene were examined. These sensors responded to sub-ppm levels of ozone, and the sensitivity decreased with increasing working temperature. The response to 0.1 ppm ozone was ca. 1000 at 250 degrees C. The conductance of the sensors in ozone decreased due to the contamination of the same VOC levels. At around 200 degrees C, the cross sensitivity of some VOCs to ozone was quite depressed. The partial substitution of Co for Fe resulted in an increased conductance in air and a decrease in the sensitivity to ozone. (C) 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.snb.2011.12.047

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE SA  

The response of the electrode potential to several volatile organic compounds was examined for a concentration cell-type oxygen sensor with a Pt|8YSZ|Pt (ref. 21% oxygen) structure. The contamination of air with ppm levels of volatile organic compounds resulted a decrease in the oxide activity at the sensing electrode with a Pt layer, i.e., a decrease in the half-cell potential. The decrease of the potential at the Pt sensing electrode was modified with an over-coating of the Pt electrode with a second material. The formation of a dense Au layer on the Pt electrode was effectively decreased the half-cell potential with the VOCs. On the other hand, the over-coating of the Pt electrode with materials having a high catalytic activity of volatile organic compounds oxidation depressed the sensitivity to the volatile organic compounds. (C) 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.snb.2011.10.063

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

The conductance changes of an SmFeO3 based p-type gas sensor due to the contamination level of air with ozone were examined. The conductance was responsive to sub-ppm levels of ozone. The dynamic range of the sensor to distinguish the air quality due to ozone contamination covered four levels, i.e., very good, good, poor and very poor. (C)2011 The Ceramic Society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.119.926

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER SCIENTIFIC PUBLISHERS  

Porphyrin-dispersed polymer composites coated on a glass rod were applied for fiber-optic HCl sensors. Tetraphenylporphine (TPPH(2)) and analogous compounds were used as an HCl indicator, while hydroxypropyl cellulose (HPC) and other polymers were chosen as matrices. The optical response to HCl gas was fairy dependent on the polymer matrices in the composite layer. Among the polymers HPC exhibited the highest sensitivity at low HCl concentration, and the spectral change due to the equilibrium reaction, TPPH(2) + 2H(+) double left right arrow TPPH(4)(2+), was detectable at &gt; 0.8 ppm. The sensor response became saturated at &gt; 4 ppm. The detectable HCl concentration range was adjustable by varying sensing temperature, porphyrin concentration, and matrix. Introducing the electron-donating substituents such as -OCH(3) and -OH effectively enhanced the sensitivity at low HCl concentration.

DOI： 10.1166/sl.2011.1431

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記述言語：日本語   出版者・発行元：公益社団法人 石油学会  

我々はこれまでに、固体酸化物形燃料電池（SOFC）の電極作製に電気泳動堆積（EPD）法を応用し、その有効性を報告してきた。本研究では、酸素イオン導電体を用いたSOFCのNi-YSZサーメットアノード作製にEPD法を適用し、電極と電解質との親和性やガスの拡散性の改善を試みた。 特に、Niの濃度勾配をつけたNi-YSZサーメットアノードが燃料電池性能を向上させることがわかった。

DOI： 10.11523/sekiyu.2011f.0.168.0

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

La0.8Sr0.2MnO3 (LSM) cathode films for a solid oxide fuel cell (SOFC) were formed on a solid electrolyte sheet using the electrophoretic deposition (EPD) technique. The EPD process was undertaken in methanol suspensions containing LSM particles with different mean particle sizes. The zeta potentials of the LSM dispersions in methanol tended to decrease with increased sintering temperature during powder preparation. The morphology of the cathodic films was significantly dependent on the mean particle size and the grain sizes in the films after sintering at 1100 degrees C were in the order of LSM600 &gt; LSM1000 &gt; LSM800, with corresponding cathodic performance in the order of LSM800 &gt; LSM1000 &gt; LSM600. The morphology of the LSM 800 films varied with the DC voltage applied during the EPD process (7.5 and 15 V), and a more densely deposited phase with finer pores was achieved with lower applied voltage. Increase in applied voltage tended to induce particle growth; therefore, the film applied at low voltage exhibited the highest cathodic performance. The cathodic performance was not dependent on the film thickness in the range between 5 and 15 mu m, which implies that the LSM800 film was sufficiently porous to provide a suitable rate of oxygen gas diffusion. (C) 2010 The Ceramic Society of Japan All rights reserved.

DOI： 10.2109/jcersj2.118.1202

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE SA  

Potentiometric oxygen sensors with Pt vertical bar YSZ vertical bar Pt structure were applied for detecting several volatile organic compounds (VOCs: acetic acid, methylethyl ketone, ethanol. benzene, toluene, o- and p-xylene) at sub-ppm levels in the temperature range of 400-500 degrees C. The electromotive force (EMF) output from the sensors linearly changed with logarithm of VOC concentration, and sufficiently large output was confirmed at sub-ppm levels. Among the examined VOCs, ethanol exhibited the highest sensitivity (-54.1 mV/decade) at 400 degrees C. However, the sensitivity of ethanol drastically decreased at 500 degrees C. Thus the sensitivity of all the VOCs examined in this study was tunable with temperature. An increase in temperature decreased the sensitivity but effectively modified the response and recovery times. Analysis of multi-dimensional plots combining the sensor outputs at the different operating temperatures (400,450 and 500 degrees C) suggested the possibility to discriminate the different VOCs. (C) 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.snb.2009.09.001

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE SA  

Potentiometric oxygen sensor was fabricated and applied to detect several volatile organic compounds (VOCs; acetic acid, methylethylketone (MEK), ethanol, benzene, toluene, o- and p-xylene) at sub-ppm levels in the temperatures range of 400-500 degrees C. The electromotive force (EMF) linearly changed with the logarithm of VOC concentration. Especially for ethanol and MEK, the sensitivity and EMF at 1 ppm were distinctly lowered for the sensor with the SmFeO(3) coated Pt working electrode. It seems that ethanol and MEK were more easily oxidized on the SmFeO(3) surface than the other VOCs. A discriminative detection of ethanol and MEK apart from the others could be achieved with the combination of two types of the sensors, Pt|8YSZ|Pt(ref.) and SmFeO(3)/Pt|8YSZ|Pt(ref.). (c) 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.snb.2009.07.026

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE SA  

A Nafion-TMPyP composite film was used in an optical humidity sensor. The composites were prepared with various molar ratios between the sulfonic groups and TMPyP molecules, R = [-SO(3)H]/[TMPyP]. The UV-vis measurement of the composite films suggested that the TMPyP molecules were well dispersed at in the range of R = 60-100, but formed aggregates at R &lt;= 20. Furthermore, the FTIR indicated that sulfonic group interacted with TMPyP. The reflectance change with relative humidity (%RH) occurred at 426.4 and 465.4 nm with the isosbestic point at 437.5 nm, and also in the Q-band region. The sensors of R = 30 and 40 sensitively responded to humidity in the lower humidity region (10-20% RH), but saturated or even decreased with further increase in humidity. At R = 60, the sensitivity slightly decreased but a measurable range was extended to around 70% RH. Remarkable deterioration in sensitivity occurred at R = 100. The TMPyP molecules were stably immobilized on a Nafion matrix, even in liquid water, without solving out. (c) 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.snb.2009.07.033

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：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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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：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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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

The electrochemical performances and the morphologies of Ni/SDC anodes fabricated by EPD technique were investigated for direct oxidation of dry CH(4) in solid oxide fuel cells (SOFCs). Ni/SDC(EPD) anode with both 20 wt% of Ni content and 20 mu m of thickness exhibited the lowest overpotential and the highest maximum power density for dry CH(4)-air SOFC at 973 K. The power density of the cell with Ni/SDC(EPD) anode was higher than that with Ni/SDC fabricated by a conventional slurry coating method. It was found that Ni/SDC(EPD) anode having dense structure suppressed carbon deposition and exhibited a stable cell operation in SOFC using dry CH(4). (C) 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.cattod.2008.08.027

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

The perovskite-type SmFeO(3) powders were prepared by the four different methods, named decomposition method of heteronuclear cyano complexes (CN), polymer precursor method (PP), reverse micelle method (RM) and reverse homogenous precipitation method (RHP), and their catalytic activities were evaluated with a CO oxidation reaction. The surface areas and the surface chemical compositions of Sm, Fe, O and C were strongly dependent on the preparation methods and calcination temperatures. On the basis of such the characteristics on the surface the factors controlling the catalytic activity are discussed. (C) 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.cattod.2008.08.014

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER SCIENTIFIC PUBLISHERS  

Optical pH sensors with porphyrin molecules, 5,10,15,20-tetrakis(4-aminophenyl)-21H,23H-porphine (TAPP) and 5,10,15,20-tetra(4-pyridyl)-21H,23H-porphine (TPyP), immobilized on a polystyrene cuvette were fabricated and their sensing properties to the solutions with a pH range of 1.0-12.5 were examined. The characteristic Soret- (similar to 460 nm) and Q-bands (similar to 680 nm) of the porphyrin molecules were sensitively changed in its intensity with the change in pH. High sensitivities were obtained for the TAPP sensor both in the Soret- and Q-band regions at pH &lt; 8. The TPyP sensor started to respond in its Soret-band at pH &lt; 6 but significantly high sensitivity was obtained at pH &lt; 3. The TAPP sensor exhibited a fast response and good reproducibility in the pH region. On the other hand, the TPyP sensor was lack of reproducibility in acidic region. Both the sensors exhibited a good stability at pH = 1 owing to the immobilization of the porphyrins.

DOI： 10.1166/sl.2008.519

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

A series of Li2O-La2O3-SiO2 sinters were prepared with the various ratios of the associated elements, Li: La: Si = x: (10-x): 6, and their ionic conductivities were examined. All the sinters; were mainly composed of the apatite-type LixLa10-x(SiO4)(6)O3-x crystalline phases but sub-phases were produced in some cases. The lattice parameters of the main phase decreased with an increase in the Li-content, x, up to x = 2.0 and became constant above x = 2.0, indicating that La 4f-site was partially replaced by Li up to the maximum of x = 2.0. The conductivity of the sinters gradually increased with an increase in x to 1.5, but it suddenly dropped down at x = 2.0 and increased again by a further increase in x. The XRD and Si-29-NMR results suggested that the first conductivity increase was due to the decrease in the content of the La2SiO5 sub-phase with the Li replacement. Furthermore, the Li-7-NMR measurements gave evidence that lithium silicate sub-phase was formed at above x = 2 in the grain-boundary of the crystalline phase as a high Li-ionic conducting phase. The Nernst's EMF response of the O-2 and CO2 oncentration cells suggested that the main ionic carriers were oxide ion at x &lt; 2.0 and lithium ion at x &gt;= 2. (C) 2008 The Ceramic society of Japan. All rights reserved.

DOI： 10.2109/jcersj2.116.803

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：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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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

A series of Li-doped lanthanoide silicates, LixLn 1-x(SiO4)6O3-x (Ln=La, Nd), were prepared by the solid phase reaction and their ionic conductivities were evaluated. The Li-doping gave the apatite crystal structures (hexagonal, P6 3/m) analogous to Ln10(SiO4)6O 3. The Li-doping was limited up to around x=2 for Ln=La and around x=3.5 for Ln=Nd. In the region of low Li-contents, oxide ion conduction characteristic for Ln10(SiO4)6O3 was still dominant. With an increase in the Li-content, the component of Li-ion conduction emerged due to the formation of lithium silicate glassy phase existing at the grain-boundaries. The O2 and CO2 sensor measurements using the sinters well supported the results of the conductivity analyses. Thus it was found that varying the Li-content could regulate an ionic conductivity and carrier. These properties of the Li-doped lanthanoid silicates might give a good compatibility into the two conduction layers junction, oxide ion conductor//alkali ion conductors fundamental to solid electrolyte gas sensors. © The Electrochemical Society.

DOI： 10.1149/1.2981160

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Electrical conductivity of a series of Ln(9.33+x/3)Si(6-x)M(x)O(26) (Ln=La, Nd and Sm, M=Al and Ga) sinters was examined. The pre-exponential factor and activation energy of the ionic conduction were well related by Meyer-Neldel rule, i.e., G = G(00) exp (Delta E/kT(0)) exp (-Delta E/kT). Most of the sinters were composed with an apatite-like phase in major and sub-products such as LnSiO(5) and Ln(2)O(3) in minor proportions. The single phases with apatite-like structure were obtained for the composition of x = 1.5. At this composition, the activation energy increased with a decrease in the ionic radius of Ln. The lowest activation energy and highest pre-exponential factor were observed for the combination of Ln = La and M = A]. This result was interpreted by considering the formation of the 4e sites for oxygen with under occupancy and oxygen ion interstitials surrounded with six 6h (La) sites.

DOI： 10.2109/jcersj2.115.643

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：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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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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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：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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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：ELECTROCHEMICAL SOC INC  

The anode performances of Ni/(CeO2)(1-x)(LnO(1.5))(x) (Ln: La, Pr, Nd, Sm, Gd, and Yb) were investigated in direct-methane solid oxide fuel cells. Among the anodes tested in the present study, Ni/CeO2-Sm2O3 and Ni/CeO2-Yb2O3 composite anodes showed relatively low anodic overpotential. The anodic overpotential of Ni(x wt%)/(CeO2)(1-y)(SmO1.5)(y) depended strongly on Ni content, while it less depended on Sm content. The catalytic activity of methane oxidation was measured for Ni/LnDC at 973 K and Ni/CeO2 and Ni/CeO2-Yb2O3 samples showed high catalytic activity. This result suggests that the activity for the direct oxidation of methane by O-2 is not the main factor controlling the anodic overpotential in direct-methane solid oxide fuel cell.

DOI： 10.1149/1.2729281

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：ELECTROCHEMICAL SOC INC  

Metal wire meshes were coated with electrode materials such as La0.8Sr0.2NbO3 and NiO/YSZ by electrophoretic deposition (EPD) and used as current collectors for a solid oxide fuel cell. The current interrupt analysis for the electrodes attached with the wire mesh current collectors clearly indicated that coated wire meshes remarkably reduced the cathodic and anodic resistances, especially polarization component, compared to using the uncoated meshes. This reduction of the electrode resistances is due to the fact that EPD coating of the metal meshes increases effective contact area and/or points between the wire mesh and electrode surface. A single cell with the EPD coated meshes exhibited higher I-V characteristics compared to that with the uncoated meshes as expected from the result of the electrode resistance measurements.

DOI： 10.1149/1.2729235

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：ELECTROCHEMICAL SOC INC  

The anode performances of Ni/(CeO2)(1-x)(LnO(1.5))(x) (Ln: La, Pr, Nd, Sm, Gd, and Yb) were investigated in direct-methane solid oxide fuel cells. Among the anodes tested in the present study, Ni/CeO2-Sm2O3 and Ni/CeO2-Yb2O3 composite anodes showed relatively low anodic overpotential. The anodic overpotential of Ni(x wt%)/(CeO2)(1-y)(SmO1.5)(y) depended strongly on Ni content, while it less depended on Sm content. The catalytic activity of methane oxidation was measured for Ni/LnDC at 973 K and Ni/CeO2 and Ni/CeO2-Yb2O3 samples showed high catalytic activity. This result suggests that the activity for the direct oxidation of methane by O-2 is not the main factor controlling the anodic overpotential in direct-methane solid oxide fuel cell.

DOI： 10.1149/1.2729281

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE SA  

The porphyrin dispersed sol-gel composite films were prepared from the different molar ratios of methyltriethoxysilane (MTEOS) to tetraethoxysilane (TEOS), M/T (=4, 8, 16 and 32), and optochemical detection of hydrogen chloride (HCl) gas (0.5-5.0ppm) was examined by using the photo-reflection spectral technique. The optical spectra of the films showed an intense Soret-band at lambda(m) of 419.3 nm for M/T = 4-16 and 418.3 nm for M/T = 32. The sensitivity of the sensors measured at the Soret-band strongly depended on the M/T ratio of the sol-gel films and to 0.5ppm it resulted in the order of M/T=8 &gt; 4 approximate to 16 &gt; 32. From the thermogravimetric (TG) analysis, it was found that M/T=4 contained a predominantly large amount of water adsorption. It is predicted that M/T = 8 has the highest adsorption capacity of HCl to exhibit the highest sensitivity. However, at high concentration of HCl (&gt;= 2.8 ppm) M/T = 4 exhibited a comparable sensitivity to M/T = 8 probably due to the large amount of water adsorption property of M/T = 4. In spite of the high sensitivity to HCl gas, the M/T = 8 sensor was almost silent to the 0.5 ppm SO2 exposure. (c) 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.snb.2005.11.039

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：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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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JOHN WILEY & SONS INC  

The reaction kinetics of the isocyanate group in the side chain of polymethacrylates with alcohol is described. The polymethacrylates were prepared by copolymerizations of 2-isocyanatoethyl methacrylate (IEM) with methacrylate monomers having five different alkyl esters. In IEM-monomer (IEM-MMA) and IEM-BnMA, the isocyanates are isolated from each other by a spacer of the ester side chain to maintain their high reactivity. In IEM-nBuMA and IEM lauryl methacrylate (LMA), the isocyanates are segregated from the long alkyl chain into its high-concentration domain, and this contributes to the acceleration effect in the early stage of the reaction.

DOI： 10.1002/pola.21127

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：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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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JOHN WILEY & SONS INC  

A novel 5-membered cyclic dithiocarbonate (DTC) having a hydroxy group, 5-hydroxymethyl-1,3-oxathiolane-2-thione (DTC-OH), was synthesized from glycidol. On the basis of the highly efficient reaction of its hydroxyl group with isocyanate, a polyurethane having isocyanate terminals was modified with DTC-OH into a new type of polyurethane prepolymer having DTC-terminals, which was highly reactive with amines but tolerant to moisture.

DOI： 10.1002/pola.20872

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：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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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：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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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE SA  

The optochemical sensing performances of the porphyrin dyes dispersed in ethylcellulose (EC) matrix to toxic gases such as HCl, NO2 and SO2 were examined using a photo-reflection spectrum technique. The intensity of the characteristic Soret- and Q-bands of the porphyrins sensitively changed with the concentration of the gasses. Introducing electron-donating -OCH3 and -OH groups to the phenyl-group in the tetraphenylporphyrin (TPPH2) molecule enhanced the sensitivity and that was in the order of TP(4-OH)(4)PH2 &gt; TP(3,5-OCH3)(4)PH2 &gt; TPPH2 to HCL In contrast, electron-withdrawing -COOH group decreased in the sensitivity. It was interpreted that the electron density at the pyrrole nitrogen increased with the electron-donationing groups. Doping of dioctylphthalate (DOP) as a plasticizer to the porphyrin-EC composites remarkably modified their sensitivity and response behavior. The sensitivity to NO2 was extremely high and sub-ppm level of detection was possible for all the composites. In the case of SO2, the sensitivity was lower than NO2, but the composite of TP(4-OH)(4)PH2 exhibited enough sensitivity to detect the concentration of 0.5 ppm. The sensing performance was strongly dependent on the humidity. (c) 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.snb.2004.10.055

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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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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 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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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：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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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：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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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：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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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Compounds having two p-phenoxyl radicals bridged by a 1,2-diphenylenedisilanylene unit in m, p- and p,p- fashions were synthesized and the intramolecular spin-spin interaction was examined by Curie plots of ESR signal intensities due to the Δ M S=±2 transition at low temperature. It was found that bridging two phenoxyl radicals at meta and para positions of the bridge led to triplet ground state or degeneracy of triplet/singlet states. In contrast, two phenoxyl radicals put at both para positions interacted in an antiferromagnetic fashion through the diphenylenedisilanylene bridge, to realize singlet ground state. © 2003 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jorganchem.2003.09.004

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE SA  

Compounds having two p-phenoxyl radicals bridged by a 1,2-diphenytenedisilanylene unit in m,p- and p,p- fashions were synthesized and the intramolecular spin-spin interaction was examined by Curie plots of ESR signal intensities due to the DeltaM(S) = +/- 2 transition at low temperature. It was found that bridging two phenoxyl radicals at meta and para positions of the bridge led to triplet ground state or degeneracy of triplet/singlet states. In contrast, two phenoxyl radicals put at both para positions interacted in an antiferromagnetic fashion through the diphenylenedisilanylene bridge, to realize singlet ground state. (C) 2003 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jorganchem.2003.09.004

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：RADIATION RESEARCH SOC  

We have provided evidence that long-lived radicals, produced by ionizing radiation, are highly mutagenic and transforming in mammalian cells. Long-lived radicals are scavenged effectively by vitamin C or by epigallocatechin-3-O-gallate (EGCG). Long-lived radicals are not involved in lethality or in the induction of chromosome aberrations. We now report the results of experiments that define the relative amounts of long-lived radicals in DNA and proteins and identify the major protein radicals as sulfinyl radicals (R-CH2-S-O-.). To make these assignments, yields of long-lived radicals in gamma-irradiated salmon sperm DNA and albumin were compared by ESR. ESR spectra of long-lived radicals produced in irradiated Syrian hamster embryo (SHE) cells were analyzed precisely and compared with ESR parameters obtained by density functional theory calculations. Long-lived radicals yields of 99.8% were produced in proteins. We also identified a new type of long-lived radical as H-added phenylalanine radicals. While our evidence does not rule out the possibility of important biological consequences of the low-level long-lived radicals created by radiation, it implicates radicals in proteins as playing a key role in genetic effects of ionizing radiation. We suggest that these novel radicals, wherever they reside, need to be considered in explanations of biological sequela of radiation. (C) 2003 by Radiation Research Society.

DOI： 10.1667/RR3015

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DOI： 10.1016/j.snb.2003.08.013

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

X-irradiated Li(N2D5)SO4 single crystals were investigated using EPR and ENDOR spectroscopy. The N-14-ENDOR spectra of the deuterated hydrazine radical cation N2D4.+ were clearly observed at 240 K. N-14 hyperfine (life) and nuclear quadrupole (nqc) tensors of the N2D4.+ cation were determined from angular variation ENDOR measurements in the three orthogonal planes of the crystal. The life tensor obtained for the two equivalent N-14 atoms is very close to that reported in a N2H5HC2O4 single crystal, and the present results support the previous conclusion that the cation has a planar structure at 240 K. The N-14 nqc tensor was estimated using semiempirical methods and also calculated from the field gradients in the LiHzS crystal as evaluated by density functional theory methods. The general agreement with experimental observations further supported the suggested geometrical structure of the N2H4.+ radical. The H-1 and N-14-ENDOR enhancements observed may be due to weakened dipolar interactions between N-14-D-2 and H-1-D-2 leading to increased T-ln relaxations of the N-14 and residual H-1 nuclei of the N2D4.+ cation (and/or other isotopomers) in the deuterated crystals as compared to those in the Li(N2H5)SO4 crystals.

DOI： 10.1021/jp0125303

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE SA  

The mobilities of positive charge carriers in polyaniline films measured as a function of oxidation level are discussed with the help of in-situ ESR measurements. Three different processes are found to occur over oxidation levels ranging from 0.1 to 43%. An initial decrease of mobility is followed by a small hump at oxidation levels up to 7%. This mobility change is ascribed to a change in conformation from coil to expanded coil. which is supported by optical absorption spectra. The rise in mobility from an oxidation window of 7 to 36% can be interpreted well in the framework of a polaron lattice model. ESR data provide strong evidence for the transformation between Curie and Pauli spins. The decrease in the mobility above the 36% oxidation level is accounted for in terms of a transition from the emeraldine salt to the base form. (C) 2002 Published by Elsevier Science B.V.

DOI： 10.1016/S0022-0728(01)00689-1

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

The EPR spectra of the radical cations of CH3OCH2F and CH3OCH2Cl generated in CF3CCl3 matrices by ionizing radiation at 77 K were fully analyzed with the help of their selectively deuterated compounds. The spectra were analyzed in terms of hyperfine coupling constants (hfcc) to the H-1 nuclei in the CH3 and CH2X (X = F, Cl) groups. Based on the EPR results combined with ab initio and DFT MO calculations, the conformation of the cations was determined; the halogen atom preferentially occupies a position in the molecular C-O-C plane which is perpendicular to the unpaired electron orbital of the central oxygen and the C-O-C-Cl framework has a geometry corresponding to a cis conformation. The temperature-dependent EPR spectra for CH3OCH2Cl+ in CF3CCl3 observed between 50 K and 100 K were analyzed in terms of a three-site chemical exchange model among the three protons, caused by CH3 group rotation. The observed activation energy for the rotation, 3.3 +/- 0.5 kJ mol(-1), is in reasonable agreement with the value calculated for the potential barrier of the rotation.

DOI： 10.1039/b200437b

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

Nitrogen monoxide (NO) introduced into partially and fully lithium ion (Li+)-exchanged A-type zeolite was studied by X-band EPR measurements. Two types of NO species, NO monoradical and NO-NO biradical, were detected for the partially ion-exchanged zeolite, while the latter was less detectable for the fully ion-exchanged one. The EPR parameters of the NO monoradical provided evidence that the electrostatic field associated with Li+ ions in A-type zeolites is weaker than that with Na+ ions. It was found that the molecular distance of NO biradical formed in partially Li+-exchanged zeolite was shorter than that in sodium ion-exchanged A-type zeolite.

DOI： 10.1039/b203930c

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

The EPR spectrum of the CH2ClOCH2Cl+ radical cation, generated by ionizing radiation in a halocarbon matrix at 77 K, consists of a major septet due to two equivalent Cl nuclei and an additional triplet due to two protons in the terminal CH2Cl groups. This assignment was confirmed using CD2ClOCD2Cl+. Theoretical calculations were performed to obtain the optimized geometries and theoretical hyperfine coupling constants (hfcc) for CH2ClOCH2Cl+ using density functional theory (DFT). The results suggested Structures I (with C-s symmetry) and II (with C-2 symmetry), where the two Cl, two C and one oxygen atoms make a five-membered ring and the unpaired electron is largely and equally shared by the two Cl nuclei. A reasonable magnitude in the proton coupling was obtained only for Structure I, having an energy lower than that of Structure II. The results were compared with those in our previous study on Cl(CH2)(3)Cl+, giving similar EPR spectra. For Cl(CH2)(3)Cl+, a geometry corresponding to Structure II was suggested from the proton coupling calculated by the CNDO/2 method. In this study, we reexamined the calculation by the DFT method and reached the conclusion that Cl(CH2)(3)Cl+ preferred a structure corresponding to Structure I.

DOI： 10.1039/b200440b

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

Structures of dimeric radical cations of fluorinated benzenes (C6H5F+ and 1,4-C6H4F2+) formed by gamma-in solid halocarbon matrices were investigated by means of EPR and DFT calculations. For both the dimer cations, sandwich type structures, where the two benzene rings are symmetrically overlapped, were suggested, and the F-19-hyperfine coupling constants of the dimeric cations were found to be smaller than half that of the corresponding monomer cations. This was qualitatively explained in terms of the anti-bonding feature of the C-C bond between the two benzene rings and the C-F bond. DFT calculations performed for the monomer and dimer cations successfully account for this phenomenon. Anisotropic F-19 hyperfine coupling (b) was used as a good indicator for evaluating the distance between the two benzene rings. The formation of the dimer cations strongly depends on the matrices and the concentration of the solutes, suggesting that molecular diffusion in the solid systems is an important factor in the dimerization.

DOI： 10.1039/b207622e

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Structures of a series of silylnitrenes formed from silyl azides were investigated by means of ESR. γ-Irradiation and photo-illumination of all the silyl azides resulted in the formation of triplet states even for those having two or three Si-N 3 groups in a molecule. ESR spectra of the silylnitrenes exhibited a part of the fine structure at around 820 mT. All the silyl azides studied gave nearly identical D-values (ca. 1.5cm -1) and much larger than those in phenylnitrenes. The results suggested that electron spins are localized in the nitrogen p-orbitals to a large extent and was interpreted in terms of a mono-silane linkage of nitrene, -Si-N:, i.e., interrupting spin delocalization. © 2001 Elsevier Science B.V.

DOI： 10.1016/S0009-2614(01)01112-5

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

Local structures and motions of radical reactants in highly selective tunneling abstraction reaction in neopentane-ethane mixture are investigated with CW-ESR, ENDOR, and ESEEM spectroscopy at different temperatures. H atoms produced by the radiolysis of neo-C5H12 in the neo-C5H12-C2H6 (2 mol %) mixtures above 40 K react selectively with the solute C2H6 to give ethyl radicals. The selective reaction is suppressed below 30 K. The local structures of neopentane matrix around neopentyl and ethyl radicals are approximately the same in the temperature range from 4.4 to 45 K. Although neopentyl radicals are rigidly trapped below 100 K, ethyl radicals in neopentane matrix begin to librate even at 6 K and increase the degree of motion up to 30 K, Finally, the librating motion of the ethyl radicals in neopentane matrix is vigorous above 40 K. The ethane molecule can take more favorable orientation for the hydrogen abstraction reaction by H atoms than rigid neopentane molecules by the vigorous libration motion, resulting in the selective reaction with H atoms.

DOI： 10.1021/jp003396+

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

The nature of quartet state nitrogen atoms formed in gamma -irradiated NaN3 powder was investigated by EPR, ENDOR and ENDOR-induced EPR (EIE). The ENDOR spectrum observed at 110 K clearly showed two sets of N-14 signal pairs centered at a(N)/2 (half the N-14-hyperfine splitting) and at 3a(N)/2, strongly suggesting the existence of quartet state N-14 atoms (S-4(3/2)). At 160 K, the EPR spectrum exhibited a clear fine structure. accompanied by a hyperfine coupling due to N-14. The zero-field splitting, D, gradually increased with decreasing temperature from 170 to 40 K, and then became nearly constant. The temperature dependence of D was explained in terms of a local lattice vibration coupled with spin states of N-14 atoms. At below 95 K, a new fine structure with larger D was observed. The observed two D-values were attributed to 14N atoms located at two different interstitial sites in the monoclinic NaN3 structure.

DOI： 10.1039/b104380n

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The a-proton hyperfine coupling observed by electron paramagnetic resonance (EPR) spectroscopy on the radical &#039;CH(COOH)2 in irradiated crystals of malonic acid, CH2(COOH)2, has served as a standard against which hundreds of observations of similar couplings-have been held and scaled. The major doublet of the malonic acid radical is accompanied by less intense &quot;forbidden&quot; &#039;(0 a-proton transitions and &quot;spin-flip&quot; (s) transitions due to weakly interacting protons. Both s and f transition lines exhibit microwave power saturation behaviors different from that of the major doublet. At high microwave power, the prominence of these s and f lines may be misinterpreted as originating from different radical species. Computer simulations could help distinguish between the different cases, but no computer simulation programs taking into account the microwave power saturation case are commonly available. On the basis of classical line-shape theory, an algorithm describing the microwave power dependence of an EPR line shape has been developed and implemented in an existing simulation program. To test this new program, malonic acid was selected because of the simplicity of its EPR spectra. However, sufficiently detailed information about the hyperfine coupling parameters for a satisfactory simulation of the room-temperature data (including s and f lines) was not available in the literature. Therefore, a detailed room-temperature EPR/ENDOR study on a single crystal of malonic acid was performed. In addition to the major a-proton coupling, seven weaker proton interactions have been characterized and partly identified. Simulations under nonsaturating conditions reproduce very well all features of the experimental EPR spectra. Simulations under saturating conditions similarly reproduce the power-dependent EPR spectra and yield information about the relaxation behavior of the radical system, which is amenable to verification using other spin-resonance methods. © 2000 American Chemical Society.

DOI： 10.1021/jp000282p

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Triplet state NO dimers stabilized on the surface of sulfated zirconia (g⊥=1.993, g∥=1.942, D⊥=195 G, E≈0 ) have been observed by ESR. They are formed by adsorption of NO molecules on pair (acceptor) surface sites represented, most likely, by two adjacent (d=5.2 Å) low-coordinated Zr4+ ions. A new single line (Lorentz line with g=1.993 and line width 18 G) of NO monomers adsorbed on active sites of sulfated zirconia has been observed. The sites where this form is stabilized seem to be very strong electron acceptors responsible for the formation of radical cations after adsorption of aromatic molecules.

DOI： 10.1016/S0009-2614(00)00856-3

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/jp000283h

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

In single crystals of malonic acid grown from heavy water, the methylene protons have been partially exchanged with deuterons. Upon X irradiation at room temperature, the (CD)-C-.(COOD)(2) radical is formed in an amount comparable to the (CH)-C-.(COOD): radical species. In the present work, EPR and ENDOR analyses of the a-deuteron hyperfine coupling (hfc) and nuclear quadrupolar coupling (nqc) tensors at room temperature have been performed. The hyperfine coupling tensor is, when scaled with the differences in the nuclear g-factor, almost identical to the a-proton coupling of the (CH)-C-.(COOH)(2) radical at room temperature. The quadrupolar coupling tensor was found to be virtually coaxial with the hyperfine coupling tensor. The quadrupolar coupling constant is 149.8 +/- 1 kHz, and the asymmetry factor eta = 0.092 +/- 0.020. It is known that, at room temperature, the malonic acid radical exhibits thermal motion between two potential energy minima separated by about +/-12 degrees. Assuming that the observed hfe and nqc tensors are the result of thermal avenging between these two conformations of the radical, a simple two-site jump model was used to estimate the rigid-limit tensors. The most significant result obtained was for the nyc tensor, for which the calculations resulted in a quadrupolar coupling constant of 160 kHz and an asymmetry factor eta = 0.026. These values are fairly close to the nqc parameters for the methylene deuterons in malonic acid at low temperature. The quadrupolar coupling tensor has been theoretically modeled using Slater orbitals and formal electronic populations, as well as electron populations obtained from RHF/CI INDO-type calculations. The simple model to compute the electric field gradient at the alpha-deuteron caused by the charge distribution at the sp(2)-hybridized alpha-carbon was found to be as successful as more advanced methods. Furthermore, density functional theoretical (DFT) calculations for both the malonic acid radical and the native malonic acid molecule have been performed. Field gradients calculated by the DFT method significantly overestimate the quadrupolar tensors for both the alpha-deuteron of the radical and the methylene deuterons of the malonic acid molecule. Calculations using electron populations from the RHF/CI INDO calculations show that contributions to the quadrupolar coupling tensor from electrons and nuclei beyond the nearest-neighbor atom of the Jeuteron are significant.

DOI： 10.1021/jp000283h

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

The structure and dynamics of the radical cations produced from benzene, monodeuterated benzene and toluene in various low-temperature matrices were characterized by EPR and ENDOR spectroscopy. It was found that the nature of the matrix had a dramatic effect on the EPR spectra of benzene cation. Rigid structures corresponding to the B-2(1g) and B-2(2g) states are revealed in solid argon and halocarbon (CFCl3) matrices, respectively, whereas only dynamically averaged patterns are observed in other hosts used (krypton, xenon, sulfur hexafluoride). Deuterium monosubstitution has no appreciable effect on the cation structure observed in argon and halocarbon matrices, which implies matrix control of the preferred electronic state. In contrast, the toluene radical cation exhibits only a B-2(2g)-like structure both in argon and in CFCl3 matrices, that is, the internal structural effect strongly predominates over environment effects in this case. The results are discussed in qualitative terms taking into consideration the matrix and substituent effects on the charge distribution in benzene cation.

DOI： 10.1039/a906483d

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

trans-Stilbene was adsorbed in the cavities of H-ZSM-5, H-MOR and H-BEA zeolites, originating monomeric and dimeric radical cations that were studied by EPR spectroscopy. The H-BEA samples were pretreated at three progressively higher temperatures. Simulation of the spectra allowed the evaluation of the relative amounts of monomers and dimers. The nature, quantity and relative amount of monomeric and dimeric radical species were correlated to chemical and dimensional modifications of zeolite channels caused by the dealumination of the zeolite structure and extra-framework aluminium species formation.

DOI： 10.1039/b005197g

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

The structure of dimeric cations of benzene and toluene formed in X-irradiated halocarbon matrices containing relatively high concentration of the solutes was investigated. EPR and ENDOR (electron nuclear double resonance) spectra of these dimer cations were observed and accurate values of the hf coupling constants were obtained. The ENDOR spectrum of the dimeric radical cation of benzene, (C6H6)(2)(+), exhibited hf couplings due to twelve equivalent protons and the isotropic coupling (a(iso)) was almost one-half of that in the monomer cation. ENDOR transitions with a rhombic symmetry were observed in a CFCl3 matrix, whereas clear axially symmetric transitions with \A(parallel to)\ &lt; \A(perpendicular to)\ were obtained in CF3CCl3 even at 50 K. The rhombic dipolar coupling tensor was used as a parameter to evaluate the distance between the two partner rings. As regards the toluene dimer cation, (CH3C6H5)(2)(+), ENDOR transitions of the CH3 and H(4,4') protons were observed. The isotropic hf coupling of the CH3 protons deviated even more strongly from the half value, being rather close to one-third of the value of the monomer. The hf coupling of the H(4,4') protons was almost half the coupling of the monomer. It was suggested that the anomalous hf couplings of the CH3 protons were due to the interaction between the two rings through the sigma-bond. Density functional theory (DFT) calculations were employed to obtain the optimized geometries and hf coupling tensors and suggested sandwich structures in both dimers. Furthermore, the distances between the two rings and the anomalous CH3 protons hf coupling in the (CH3C6H5)(2)(+) were successfully evaluated.

DOI： 10.1039/b001174f

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

X-irradiated Li(N2H5)SO4 single crystals were investigated using ESR and ENDOR spectroscopy at several temperatures. The hydrazine radical cation N2H4.+ was selectively produced by irradiation at room temperature. From the analysis of the orientation dependent ENDOR spectra, the H-1-hfc tensors of the cation radical were precisely obtained and the radical structure was supported by theoretical calculations. It is suggested that the cation radical has a planar pi* structure D-2h (B-2(2g)) in the crystal down to 230 K. By using the evaluated H-1-hf tensor the powder ESR line shape was successfully simulated. Concomitant with the radical formation, the N-N bond of N2H4.+ is suggested to reorient so as to optimize hydrogen bond interactions. H-1-ENDOR line splitting for the N2H4.+ radical was observed at temperatures below 230 K. Apparently this splitting is due to a reversible structural change where one of the NH2 moieties in N2H4.+ becomes slightly bent out of the molecular plane, whereas the other one remains planar. This deformation evidently arises from interactions between the cation radical, adjacent H2N-NH3+ molecules and the SO4-LiO4 framework. Interacting N2H5+... N2H4.+... N2H5+ molecules along the c-axis are proposed to explain the deformation mechanism.

DOI： 10.1039/a908487h

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The radical cations of methyl-substituted benzene toluene, p-xylene, o-xylene, m-xylene, and their deuterated analogues generated in CFCl3 and CF3CCl3 matrices by X-ray irradiation at 77 K were investigated by ESR and high-resolution ENDOR spectroscopy. The ESR and ENDOR spectra in these radical cations are dominated by large axially symmetric hyperfine splitting due to methyl-group protons. The anisotropic hyperfine coupling constants (hfcc) of methyl protons and ring protons in radical cations of toluene and p-xylene were measured accurately by ENDOR spectroscopy. In the case of deuterated p-xylene and o-xylene radical cations in CF3CCl3 matrix, the hyperfme coupling constants are scaled by their magnetogyric ratio (γH/γD = 6.51). Theoretical calculations of the isotropic and dipolar hyperfine coupling constants in these radical cations are found to be in good agreement with experimental results. The experimental and theoretical calculations supported the stabilization of the 2B2g type of state for the radical cations of toluene and p-xylene compared to the stabilization of the 2B1g type of ground state for o-xylene and m-xylene due to lifting of the orbital degeneracy of the e1g orbital by lowering the symmetry obtained after substitution of hydrogen by methyl group.

DOI： 10.1021/jp9843149

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Photoinduced reactions of trans-HC≡CH- in a glassy 2-MTHF matrix were studied by ESR and electron absorption (EA) spectroscopy. ESR and EA spectra were interpreted with the aid of the results of molecular orbital (MO) calculations. The trans-HC≡CH- was generated and stabilized in the 2-MTHF matrix at 77 K by ionizing irradiation. The ESR parameters observed for the radical anion are A1 = 5.3, A2 = 4.6, A3 = 4.5 mT for two equivalent 1H atoms, A⊥ = 1.5, A∥ = 4.2 mT for two equivalent 13C atoms, and g1 = 2.0009, g2 = 2.0024, g3 = 2.0029 for the g tensor. By illuminating with light of λ ≥ 430 nm, the trans-HC≡CH- was found to be irreversibly isomerized into the vinylidene radical anion, H2C=C-, in the matrix. The experimental ESR parameters of H2C=C- [A1 = 5.4, A2 = 6.0, A3 = 5.7 mT for two equivalent protons, g1 = 2.0026, g2 = 2.0008, g3 = 2.0026] were fully consistent with the results obtained by semiempirical MO methods, (1) INDO and Analytical Dipolar Calculation method (ANADIP) for isotropic and anisotropic 1H hyperfine (hf) couplings, respectively, and (2) AM1 for the g tensor, for a geometrical structure optimized by ab initio method (Gaussian90/uhf/6-31++G**). The structure of the anions was in agreement with the results obtained from the EA spectroscopic study. The photoinduced isomerization was initiated by the light absorption at λ ≥ 430 nm of trans-HC≡CH-. The EA band at λmax = 374 nm observed for H2C=C- was attributed to the electron transition from the 2B2 ground state and to the 2A1 excited state.

DOI： 10.1021/jp990484p

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

A combination of EPR lineshapes, ENDOR and ESEEM was performed to investigate possible Jahn-Teller effects in mono- and perdeuterated benzene radical cation in a polycrystalline CFCl3 matrix. Replacement of one proton by a deuteron was utilized to exclude significantly fast quantum pseudorotation and overall rotary motion below 77 K. Clear evidence was obtained for static Jahn-Teller distortion at temperatures up to 30 K, with major spin densities on two para positions (1 and 4) in agreement with a b(2g)(chi(s)(+)) localized orbital. From ENDOR measurements of C6H5D+, the isotropic and dipolar coupling constants for protons occupying both high and low spin density positions were accurately measured. Additional ESEEM experiments and simulations confirmed the results, indicating further that deuteron-isotope substitution does not disturb appreciably the fundamental dynamics of the benzene radical benzene. The hyperfine tensors of C6D6+ in the Jahn-Teller distorted configuration obtained by ESEEM were analogous to those of fully protonated compounds, but the components were scaled by the magnetic moment ratio of deuterons to protons.

DOI： 10.1039/a905050g

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DOI： 10.1021/jp990484p

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記述言語：英語   出版者・発行元：ACADEMIC PRESS INC  

Geometries, hyperfine structure, and relative stabilities of the different positional isomers of monodeuterated benzene cations have been studied theoretically by density functional theory, using the B3-LYP functional, and experimentally by ESR and ENDOR spectroscopy. A comparison between theoretical and experimental results at 30 K gives acceptable agreement, but further experiments on multiply deuterated species should improve the analysis by making the effects of deuteration larger. © 1999 Academic Press Inc.

DOI： 10.1016/S0065-3276(08)60467-0

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：CHEMICAL SOC JAPAN  

EPR spectra for the radical cations of a series of fluorinated ethylenes and propenes, generated by irradiation with gamma-rays in halocarbon solid matrices, have been observed at low temperature. The spectra consist of a hyperfine structure with a nearly axial symmetry mainly due to fluorine nuclei. For the trifluoro olefin cations, CF2=CFX+ (X = H, CH3, or CS), the experimental spectra were successfully analyzed in terms of the three F-19 nuclei with coaxial parallel components. This may strongly suggest a planar structure for the radical cations, similarly to the case of the CF2=CF2+ cation already reported. On the other hand, for mono- and di-fluoro olefin radical cations, it is difficult to conclude the planar structure unequivocally from the experimental F-19 and H-1 hf splittings. Thus, the optimized geometry of the radical cations was calculated by an ab initio MO method. In contrast with the ethylene cation and the propene cation, having nonplanar twisted structures, the fluorinated ethylene and propene cations are concluded to have planar structures. Calculations at the INDO levels including the evaluation of interatomic dipole-dipole interactions were done for the geometries of the radical cations optimized by the ab initio method. The calculated results strongly support the EPR spectra observed and assigned to the radical cations.

DOI： 10.1246/bcsj.71.2547

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

An EPR study has been performed on a low Ag+-exchanged Na-A zeolite (Ag0.1Na11.9-A) on which ammonia had been adsorbed followed by exposure to γ-radiation at 77 K. The formation of Ag atoms, normally observed for zeolites with a high Ag content, is abated by the presence of ammonia. New EPR spectra with the silver hyperfine coupling constant slightly smaller than that of isolated silver atoms were observed. The new spectra were assigned to two silver-ammonia complexes, [Ag-NH3]0 and [Ag-(NH3)2]0 the former being more thermally stable than the latter; the latter decayed at 150 K. The EPR parameters of [Ag-NH3]0 were determined as follows: giso = 2.005 and aiso(107Ag) = 38.0, A⊥(14N) = 1.4, A∥(14N) = 1.7 and aiso(tH) ≈ 0 mT. The formation reactions and possible locations of the adduct radical are discussed in terms of annealing temperatures and the amount of ammonia introduced.

DOI： 10.1039/a707157d

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DOI： 10.1246/bcsj.71.2547

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

EPR spectra for the radical cations of a series of fluorinated benzenes, generated by irradiation with gamma-rays in halocarbon solid matrices, have been observed at low temperatures. The spectra consist of a hyperfine structure with axially symmetric anisotropy mainly due to fluorine nuclei. The observed spectra have been analysed by simulation. Ab initio calculations have been conducted for the cation radicals to obtain their optimized geometries. The results reveal that an unambiguous deformation in geometry is brought about by cationization in each case. INDO calculations have been performed for-the optimized geometries of these radical cations to calculate the hyperfine couplings. The calculated couplings strongly support the observed ones. The symmetry of the SOMO for the radical cations resembles that of the HOMO of their neutral mother molecules. The deformed geometries of these radical cations suggests that in the process of releasing an electron from an HOMO, those chemical bonds with bonding nature in the HOMO become elongated and those bonds with antibonding nature become shortened. It is concluded that the structure and symmetry of the SOMO of these radical cations are affected not only by the number of substitutions by fluorine but also by the position of substitution.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

EPR spectra for the radical cations of a series of fluorinated benzenes, generated by irradiation with gamma-rays in halocarbon solid matrices, have been observed at low temperatures. The spectra consist of a hyperfine structure with axially symmetric anisotropy mainly due to fluorine nuclei. The observed spectra have been analysed by simulation. Ab initio calculations have been conducted for the cation radicals to obtain their optimized geometries. The results reveal that an unambiguous deformation in geometry is brought about by cationization in each case. INDO calculations have been performed for-the optimized geometries of these radical cations to calculate the hyperfine couplings. The calculated couplings strongly support the observed ones. The symmetry of the SOMO for the radical cations resembles that of the HOMO of their neutral mother molecules. The deformed geometries of these radical cations suggests that in the process of releasing an electron from an HOMO, those chemical bonds with bonding nature in the HOMO become elongated and those bonds with antibonding nature become shortened. It is concluded that the structure and symmetry of the SOMO of these radical cations are affected not only by the number of substitutions by fluorine but also by the position of substitution.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：MUNKSGAARD INT PUBL LTD  

An EPR and MO study has been carried out to elucidate the electronic structure of methylacetylene (MA) radical anion generated in glassy 2- methyltetrahydrofuran matrix by ionization radiation at 77 K. The EPR spectrum was dominated by a large and slightly anisotropic H-1 hf splitting of ca. 4.53 mT due to one ethynyl proton. With the help of a selectively deuteriated methylacetylene, MA-d(3), the anisotropic hf and g-values were determined: the principal hf ((A) over tilde) and (g) over tilde values are A(xx) = 5.36 mT, A(yy) = 4.39 mT, A(zz) = 3.85 mT for, the ethynyl proton, a = 0.50 mT for the methyl protons, and g(xx) = 2.0005, g(yy) = 2.0020, g(zz) = 2.0021, respectively. From a comparison of the experimental values with the theoretical ones calculated by ab initio MO and INDO methods, a trans-bent structure was concluded for MA(-). The formation of MA(-) was also confirmed by an electron absorption spectroscopic study.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：MUNKSGAARD INT PUBL LTD  

An EPR and MO study has been carried out to elucidate the electronic structure of methylacetylene (MA) radical anion generated in glassy 2- methyltetrahydrofuran matrix by ionization radiation at 77 K. The EPR spectrum was dominated by a large and slightly anisotropic H-1 hf splitting of ca. 4.53 mT due to one ethynyl proton. With the help of a selectively deuteriated methylacetylene, MA-d(3), the anisotropic hf and g-values were determined: the principal hf ((A) over tilde) and (g) over tilde values are A(xx) = 5.36 mT, A(yy) = 4.39 mT, A(zz) = 3.85 mT for, the ethynyl proton, a = 0.50 mT for the methyl protons, and g(xx) = 2.0005, g(yy) = 2.0020, g(zz) = 2.0021, respectively. From a comparison of the experimental values with the theoretical ones calculated by ab initio MO and INDO methods, a trans-bent structure was concluded for MA(-). The formation of MA(-) was also confirmed by an electron absorption spectroscopic study.

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DOI： 10.1039/a707157d

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記述言語：日本語   出版者・発行元：電気化学会化学センサ研究会  

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記述言語：日本語   掲載種別：記事・総説・解説・論説等（商業誌、新聞、ウェブメディア）  

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記述言語：日本語   出版者・発行元：電気化学会化学センサ研究会  

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記述言語：日本語   出版者・発行元：電気化学会化学センサ研究会  

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記述言語：日本語   出版者・発行元：電気化学会化学センサ研究会  

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記述言語：日本語   出版者・発行元：触媒学会  

CiNii Books

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記述言語：日本語   出版者・発行元：電気化学会化学センサ研究会  

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記述言語：英語   出版者・発行元：公益社団法人日本セラミックス協会  

Electrical conductivity of a series of Ln_<9.33 +x/3>Si_<6-x>M_xO_<26> (Ln=La, Nd and Sm, M=Al and Ga) sinters was examined. The pre-exponential factor and activation energy of the ionic conduction were well related by Meyer-Neldel rule, i.e., G=G_<00> exp (ΔE/kT_0) exp (-ΔE/kT). Most of the sinters were composed with an apatite-like phase in major and sub-products such as LnSi_O5 and Ln_2O_3 in minor proportions. The single phases with apatite-like structure were obtained for the composition of x=1.5. At this composition, the activation energy increased with a decrease in the ionic radius of Ln. The lowest activation energy and highest pre-exponential factor were observed for the combination of Ln=La and M=Al. This result was interpreted by considering the formation of the 4e sites for oxygen with under occupancy and oxygen ion interstitials surrounded with six 6h(La) sites.

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記述言語：英語   出版者・発行元：愛媛大学  

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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その他リンク： http://iyokan.lib.ehime-u.ac.jp/dspace/handle/iyokan/1475

記述言語：日本語   出版者・発行元：電気化学会化学センサ研究会  

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記述言語：日本語  

CiNii Books

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記述言語：日本語   出版者・発行元：電気化学会化学センサ研究会  

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記述言語：日本語  

CiNii Books

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記述言語：日本語   出版者・発行元：電気化学会化学センサ研究会  

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記述言語：日本語   出版者・発行元：電気化学会化学センサ研究会  

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記述言語：日本語   出版者・発行元：電気化学会化学センサ研究会  

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記述言語：日本語   出版者・発行元：電気化学会化学センサ研究会  

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記述言語：日本語   出版者・発行元：電気化学会化学センサ研究会  

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記述言語：日本語   出版者・発行元：日本放射線化学会  

CiNii Books

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記述言語：英語   出版者・発行元：ROYAL SOC CHEMISTRY  

X-irradiated Li(N2H5)SO4 single crystals were investigated using ESR and ENDOR spectroscopy at several temperatures. The hydrazine radical cation N2H4.+ was selectively produced by irradiation at room temperature. From the analysis of the orientation dependent ENDOR spectra, the H-1-hfc tensors of the cation radical were precisely obtained and the radical structure was supported by theoretical calculations. It is suggested that the cation radical has a planar pi* structure D-2h (B-2(2g)) in the crystal down to 230 K. By using the evaluated H-1-hf tensor the powder ESR line shape was successfully simulated. Concomitant with the radical formation, the N-N bond of N2H4.+ is suggested to reorient so as to optimize hydrogen bond interactions. H-1-ENDOR line splitting for the N2H4.+ radical was observed at temperatures below 230 K. Apparently this splitting is due to a reversible structural change where one of the NH2 moieties in N2H4.+ becomes slightly bent out of the molecular plane, whereas the other one remains planar. This deformation evidently arises from interactions between the cation radical, adjacent H2N-NH3+ molecules and the SO4-LiO4 framework. Interacting N2H5+... N2H4.+... N2H5+ molecules along the c-axis are proposed to explain the deformation mechanism.

DOI： 10.1039/a908487h

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開催年月日： 2019年5月

記述言語：日本語   会議種別：口頭発表（招待・特別）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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開催年月日： 2019年3月

記述言語：日本語   会議種別：口頭発表（一般）  

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開催年月日： 2018年12月

記述言語：日本語   会議種別：口頭発表（一般）  

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開催年月日： 2018年9月

記述言語：日本語   会議種別：口頭発表（一般）  

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開催年月日： 2018年9月

記述言語：日本語   会議種別：口頭発表（一般）  

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開催年月日： 2018年9月

記述言語：日本語   会議種別：口頭発表（一般）  

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開催年月日： 2018年3月

記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：ポスター発表  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（招待・特別）  

researchmap

記述言語：日本語   会議種別：口頭発表（一般）  

researchmap

記述言語：英語   会議種別：口頭発表（招待・特別）  

researchmap

記述言語：日本語   会議種別：口頭発表（一般）  

researchmap

記述言語：日本語   会議種別：口頭発表（一般）  

researchmap

記述言語：日本語   会議種別：口頭発表（一般）  

researchmap

researchmap

記述言語：日本語   会議種別：口頭発表（一般）  

researchmap

記述言語：英語   会議種別：ポスター発表  

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記述言語：英語   会議種別：ポスター発表  

researchmap

記述言語：英語   会議種別：ポスター発表  

researchmap

記述言語：日本語   会議種別：口頭発表（一般）  

researchmap

記述言語：日本語   会議種別：口頭発表（一般）  

researchmap