Language：English   Publisher：The Ceramic Society of Japan  

Porous silica glass was prepared by phase separation of sodium borosilicate glass. The distributions of SiO_4 structural units, Q_n, were examined by ^<29>Si magic-angle spinning (MAS) NMR after each process in a series of acid and thermal treatments. The NMR spectra reveal three distinct peaks due to the presence of a silanol group on the surface of the porous silica glass. However, only a single peak around -110 ppm that originated from a Q_4 unit which lacked any OH groups could be observed after heat treatment at 900℃.

DOI： 10.2109/jcersj.105.700

CiNii Books

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Language：English   Publisher：AMER INST PHYSICS  

Hydrogen is produced by generating in-liquid plasma in a conventional microwave oven. A receiving antenna unit consisting of seven copper rods is placed at the bottom of the reactor furnace in the microwave oven. 2.45 GHz microwave in-liquid plasma can be generated at the tips of the electrodes in the microwave oven. When the n-dodecane is decomposed by plasma, 74% pure hydrogen gas can be achieved with this device. The hydrogen generation efficiency for a 750 W magnetron output is estimated to be approximately 56% of that of the electrolysis of water. Also, in this process up to 4 mg/s of solid carbon can be produced at the same time. The present process enables simultaneous production of hydrogen gas and the carbide in the hydrocarbon liquid. (C) 2009 American Institute of Physics. [doi: 10.1063/1.3236575]

DOI： 10.1063/1.3236575

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DOI： 10.1063/1.3236575

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Language：English   Publisher：SPRINGER  

Radio frequency (RF) plasma in water was used for the degradation of methylene blue. The fraction of decomposition of methylene blue and the intensity of the spectral line from OH radical increased with RF power. RF plasma in water also produced hydrogen peroxide. The density of hydrogen peroxide increased with RF power and exposure time. When pure water (300 mL) is exposed to plasma at 310 W for 15 min, density of hydrogen peroxide reaches to 120 mg/L. Methylene blue after exposed to plasma degraded gradually for three weeks. This degradation may be due to chemical processes via hydrogen peroxide and tungsten. The comparison between the experimental and calculated spectral lines of OH radical (A-X) shows that the temperature of the radical is around 3,500 K. Electron density is evaluated to be similar or equal to 3.5 x 10(20) m(-3) from the stark broadening of the H(beta) line.

DOI： 10.1007/s11090-008-9142-2

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Language：English   Publisher：JAPAN SOC APPLIED PHYSICS  

The plasma in water is generated by applying high-frequency (HF) irradiation of 27.12 MHz or microwave (MW) radiation of 2.45 GHz from an electrode. The electrode is heated by joule heating by the HF or MW irradiation, and vapor bubbles are generated simultaneously. The plasma is then ignited inside the bubbles on the electrode. The glow discharge plasma can be maintained in spite of atmospheric pressure due to the cooling effect of the liquid itself. The electron temperature of the plasma generated by the 27.12 MHz radiation is higher than that generated by the 2.45 GHz radiation. (C) 2008 The Japan Society of Applied Physics.

DOI： 10.1143/APEX.1.046002

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Language：English   Publisher：AMER INST PHYSICS  

An experiment was conducted for generating high-frequency plasma in supercritical carbon dioxide; it is expected to have the potential for applications in various types of practical processes. It was successfully generated at 6-20 MPa using electrodes mounted in a supercritical cell with a gap of 1 mm. Emission spectra were then measured to investigate the physical properties of supercritical carbon dioxide plasma. The results indicated that while the emission spectra for carbon dioxide and carbon monoxide could be mainly obtained at a low pressure, the emission spectra for atomic oxygen could be obtained in the supercritical state, which increased with the pressure. The temperature of the plasma in supercritical state was estimated to be approximately 6000-7000 K on the assumption of local thermodynamic equilibrium and the calculation results of thermal equilibrium composition in this state showed the increase of atomic oxygen by the decomposition of CO2. (C) 2007 American Institute of Physics.

DOI： 10.1063/1.2724240

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Language：English   Publisher：AMER INST PHYSICS  

An experiment was conducted for generating high-frequency plasma in supercritical carbon dioxide; it is expected to have the potential for applications in various types of practical processes. It was successfully generated at 6-20 MPa using electrodes mounted in a supercritical cell with a gap of 1 mm. Emission spectra were then measured to investigate the physical properties of supercritical carbon dioxide plasma. The results indicated that while the emission spectra for carbon dioxide and carbon monoxide could be mainly obtained at a low pressure, the emission spectra for atomic oxygen could be obtained in the supercritical state, which increased with the pressure. The temperature of the plasma in supercritical state was estimated to be approximately 6000-7000 K on the assumption of local thermodynamic equilibrium and the calculation results of thermal equilibrium composition in this state showed the increase of atomic oxygen by the decomposition of CO2. (C) 2007 American Institute of Physics.

DOI： 10.1063/1.2724240

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DOI： 10.2116/bunsekikagaku.56.511

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DOI： 10.2116/bunsekikagaku.56.511

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The generation of microwave plasma in liquid with vapor bubbles has been achieved and will soon be applied to high-speed chemical vapor deposition. Vapor bubbles are induced from an electrode by heating. The deposition rate of diamondlike carbon films depends on the pressure and the power of the microwave supply. Polycrystalline silicon carbide is synthesized on a silicon substrate in a mixture of n -dodecane and silicone oil. The dispersion of water droplets in liquid creates many pores on the silicon carbide films. The synthesis of carbon nanotubes can be achieved in liquid benzene. © 2006 American Institute of Physics.

DOI： 10.1063/1.2208167

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Language：English   Publisher：AMER INST PHYSICS  

The generation of microwave plasma in liquid with vapor bubbles has been achieved and will soon be applied to high-speed chemical vapor deposition. Vapor bubbles are induced from an electrode by heating. The deposition rate of diamondlike carbon films depends on the pressure and the power of the microwave supply. Polycrystalline silicon carbide is synthesized on a silicon substrate in a mixture of n-dodecane and silicone oil. The dispersion of water droplets in liquid creates many pores on the silicon carbide films. The synthesis of carbon nanotubes can be achieved in liquid benzene. (c) 2006 American Institute of Physics.

DOI： 10.1063/1.2208167

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DOI： 10.1063/1.2210448

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DOI： 10.2109/jcersj.112.110

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Language：English   Publisher：ELSEVIER SCIENCE BV  

The B-11, Al-27 and Si-29 magic angle spinning (MAS) NMR spectra of 0.139MO (or M-2'O)(.)0.673SiO(2)(.) (0.188 - x)Al2O3 (.) xB(2)O(3) - (M = Mg, Ca, Sr and Ba, M' = Na and K) glasses were examined. When three network forming oxides such as SiO2, Al2O3 and B2O3 coexist, Al2O3 reacts preferably with network modifier such as M-2'O or MO. The reactivity of residual network modifier with SiO2 was high compared with B2O3 in the order of K2O &lt; Na2O &lt; BaO &lt; SrO &lt; CaO &lt; MgO. The apparent equilibrium constants, K-app, of the reactions, Si(Q(3)) + B(Q(3)) = Si(Q(4)) + B(Q(4)), were determined. Here, the Si(Q(n)) or B(Q(3)) and B(Q(4)) represent the SiO2 structural units or three- and four-coordinated boron atoms, respectively. The subscript are the number of bridging oxygen atoms. The K.pp values indicate the reactivity of MO or M-2'O with B2O3 and SiO2 in the MO(M-2'O) (.) SiO2 (.) Al2O3 (.) B2O3 glasses. The reaction proceeds to the left direction in the order of MgO &gt; CaO &gt; SrO &gt; BaO &gt; Na2O &gt; K2O. The order of the reactivity is the same as that of the electronegativities among alkali and alkaline earth metals. (C) 2003 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jnoncrysol.2003.08.086

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Language：Japanese   Publisher：Japanese Society for Engineering Education  

The basic scientific and technological knowledge and experience that incoming students of our university possess have been inspected. It was clearly shown that such knowledge was based not on experience but on desk work. Usually students had not had the opportunity to obtain such knowledge in actual situations, and many students lost interest in studying engineering. In order to improve this situation and produce creativity in students, we developed a laboratory course to provide fundamental scientific and technical experience to our freshmen. This academic year(2002), over 340 students belong to four different departments will take this new course. The preliminary outcomes will be reported.

DOI： 10.4307/jsee.51.2_31

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Language：English   Publisher：Ceramic Society of Japan  

The half-wave potentials of the reduction of Fe3+ in 16M2O (M: Li, Na, K and Cs) · 10M′O (M′: Mg, Ca, Sr and Ba) · 74SiO2 glass melts were examined by differential pulse voltammetry. In all melts, the half-wave potential shifted to the positive side with increasing temperature. The equilibrium of Fe3+/Fe2+ moved toward the reduced side with increasing temperature. The replacement of Li+ ions by larger alkali ions resulted in a positive shift of the half-wave potentials. On the other hand, the smaller the ionic radius of the alkaline-earth metal ion, the larger the half-wave potential. The Fe3+/Fe2+ equilibrium was mainly affected by the stability of the Fe3+-complex and the basicity of the melts. Variations in the kinds of alkali and alkaline-earth metal ions influenced the stability of the complex and the basicity of the melts, respectively. The half-wave potential moved toward the positive side (45 mV at 1473 K) when the atmosphere over the melts was changed from pure oxygen gas to air
thus, the reversibility of Pt: O2 reference electrode was confirmed.

DOI： 10.2109/jcersj.111.723

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Language：Japanese   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Simple binary alkali borate glasses containing sulfur were prepared by conventional melt quench method and chemical bonding states of sulfur were investigated by means of ultraviolet-visible (UV-VIS) spectroscopy, X-ray photoelectron spectroscopy (XPS) and B-11 MAS-NMR measurement. The glass samples were colored and colors changed with glass composition and alkali species. The blue coloration by absorption at around 585 nm was explained with the formation of S-3(-) anion spices. On the other hand, the glass samples colored in brown or red showed absorption spectrum around 450 nm because of the formation of S-x(2-) anion (polysulfide ion) speices. S2p binding energy was around 161 eV, and this values was lower than that of orthorhombic crystalline sulfur. From these results, it was suggested that sulfur was present with a negative charge in R2S-B2O3 glasses. In colored reddish brown regions, the formation of non-bridging oxygen from O1s spectrum in the glasses was noticed. Therefore, it is suggested that the formation of nonbridging oxygen in glasses largely effect the variation of sample coloration. The estimated fraction of four-coordinated boron from B-11 MAS-NMR measurment was nearly equal to oxide glass systems. As a result, it is assumed that the effect of sulfur on the conversion of boron coordinate number is small because of a low solubility of sulfur in this glass system.

DOI： 10.2109/jcersj.110.576

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DOI： 10.2109/jcersj.110.576

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DOI： 10.1016/S0272-8842(00)00039-0

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DOI： 10.2116/analsci.17.45

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DOI： 10.2116/analsci.17.45

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Language：English   Publisher：Elsevier Science Ltd  

ZnO doped silica gels were synthesized by the hydrolysis and condensation of complex solution tetraethyl orthosilicate (TEOS) and zinc acetate (Zn(Ac)2) and heating at 500 °C in the air. For conversion to ZnS doped gels, they were exposed to H2S gas at appropriate temperatures. The crystal size of ZnS determined by the width of X-ray diffraction pattern and direct transmission electron micrograph (TEM) grows from 1 to 4 nm with an increase of reaction temperature with H2S gas. The edge energies of optical absorption shifted to higher energy side compared with that of bulk crystal and reciprocally increased in proportional to the square of the crystal size. The peak energy of fluorescence spectra also shifted to lower energy side with an increase of reaction temperature exposing to the H2S gas. Thus, the quantum size effect could be found for ZnS microcrystals in the gels.

DOI： 10.1016/S0272-8842(00)00039-0

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Language：English   Publisher：ELSEVIER SCIENCE BV  

The B-11. Al-27 Si-29 and P-31 magic angle spinning (MAS) NMR spectra of MO-P2O5, MO SiO2-P2O5 and MO(M'O-2)-SiO2-Al2O3-B2O3 (M = Mg, Ca, Sr and Ba, M' = Na) glasses were examined, in binary MO-P2O5 (M = Ca and Mg) glasses, the distributions of the phosphate sites, P(Q(n)), call be expressed by a theoretical prediction that P2O5 reacts quantitatively with MO. In the ternary 0.30MO-0.05SiO(2)-0.65P(2)O(5) glasses, the 6-coordinated silicon sites were detected. whose population increases in the order of MgO &lt; CaO &lt; SrO=BaO. In xCaO=0.05SiO(2) (0.95 - x)P2O5 glasses, its population increases with an increase in f (= ([P2O5] - [MO] - [B2O3] - [Na2O])/[SiO2]) and has maximum at f = 9. The signal due to the 5-coordinated silicon atoms is also observed when x is smaller than 0.45. When three network-forming oxides such as SiO2, Al2O3 and B2O3 coexist, Al2O3 reacts preferably with MO. The populations of 4-coordinated boron atoms, N-4, are expressed well with r/(1 - r), when r = ([Na2O] - [Al2O3])/([Na2O] - [Al2O3] + [B2O3]). The correlation of the Raman signal at 1210 and 1350 cm (1) with the NMR signal of Si(Q(6)) at -215 ppm is also seen. (C) 2000 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0022-3093(00)00056-9

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The Si-29, P-31 and B-11 magic angle spinning (MAS) NMR spectra of 30Na(2)O-5SiO(2)-65[(1 - x)P2O5-xB(2)O(3)] glasses were examined together with Raman and IR data. A correlation of the Raman signal at 1200 cm(-1) or IR signal at 660 cm(-1) with the Si-29 NMR around -215 ppm is seen. The 6-coordinated silicon atoms are observed in glasses when x is smaller than 0.250. The 3-coordinated boron atoms begin to appear in glasses with x &gt; 0.500. It is assumed that the phosphate species were made up of six types: O=P-O-3/2(P), O=P-(ONa)O-2/2(P), (NaO)-P-O-3/2(T), (NaO)(2)-P O-2/2(T), (NaO)(3)-P-O-1/2(T) and P-O-4/2(T), where O is bridging oxygen and T is either B, P or Si. The distribution curves derived from the deconvolution of the spectra by component signal of each phosphate and borate species agree with those calculated using species with different [Na2O]/[P2O5] ratios when P2O5 reacts with Na2O and B2O3 preferably. (C) 1999 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0022-3093(99)00241-0

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Language：English   Publisher：ELSEVIER SCIENCE BV  

The Si-29, P-31 and B-11 magic angle spinning (MAS) NMR spectra of 30Na(2)O-5SiO(2)-65[(1 - x)P2O5-xB(2)O(3)] glasses were examined together with Raman and IR data. A correlation of the Raman signal at 1200 cm(-1) or IR signal at 660 cm(-1) with the Si-29 NMR around -215 ppm is seen. The 6-coordinated silicon atoms are observed in glasses when x is smaller than 0.250. The 3-coordinated boron atoms begin to appear in glasses with x &gt; 0.500. It is assumed that the phosphate species were made up of six types: O=P-O-3/2(P), O=P-(ONa)O-2/2(P), (NaO)-P-O-3/2(T), (NaO)(2)-P O-2/2(T), (NaO)(3)-P-O-1/2(T) and P-O-4/2(T), where O is bridging oxygen and T is either B, P or Si. The distribution curves derived from the deconvolution of the spectra by component signal of each phosphate and borate species agree with those calculated using species with different [Na2O]/[P2O5] ratios when P2O5 reacts with Na2O and B2O3 preferably. (C) 1999 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0022-3093(99)00241-0

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DOI： 10.2116/bunsekikagaku.48.205

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Language：Japanese   Publisher：The Ceramic Society of Japan  

Sn^<4+>-Sn^<2+>redox in binary alkali silicate melts was studied by means of differential pulse voltammetry. The half-wave potential, E_<1/2> of the reduction of Sn^<4+> to Sn^<2+> shifts toward the negative with changing the alkali metal ions from Li^+ through Na^+, K^+ and Cs^+, at a fixed concentration for each alkali metal oxide. Conversely, E_<1/2> shifts to the positive with an increase in the content of each of the alkali oxide. This tendency for Sn^<4+>-S2^<2+> redox was different from those of Sb^<5+>-Sb^<3>+ and Cr^<6+>-Cr^<3+> redox. The presence of Sb^<5+> and Cr^<6+> result in a strong acid, which leads to E_<1/2> shift to the negative with an increase in basicity. These results for Sn ions can be interpreted in terms of complex formations of Sn^<4+> and Sn^<2+> in which the coordination numbers of the oxide ion for both ions do not differ significantly and their equilibrium constants for complex formation depend largely on the alkali species.

DOI： 10.2109/jcersj.107.385

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Other Link： https://jlc.jst.go.jp/DN/JALC/00060359551?from=CiNii

DOI： 10.2109/jcersj.107.385

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DOI： 10.2109/jcersj.107.895

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DOI： 10.2109/jcersj.107.895

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Language：Japanese   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Spherical porous zirconia and titania particles were synthesized by the sol-gel process from zirconyl chloride, zirconium tetrapropoxide and titanium tetraisopropoxide in W/O emulsion, respectively. Zirconia particles are obtained by addition of urea and hexamethylenetetramine in a starting solution, When the molar ratio of zirconyl chloride, calcium chloride, urea, hexamethylenetetramine, N,N dimethyl formamide and H2O is 1 i 0.2 : 1.1 : 0.9 : 1.4 : 45, spherical porous zirconia particles could be synthesized. The particles occurred cubic and monoclinic form at 600 degrees C, respectively. Peak pore-diameter of the particles was 4 nm, The pore volume increases with increase in calcium content. After the extraction of calcium by hot water, the specific surface area of the particles is enhanced 110 m(2)/g. SiO2-ZrO2 binary particles are synthesized by using zirconium tetrapropoxide and 2-methoxyethanol, When the molar ratio of tetramethoxysilane (TMOS), zirconium tetrapropoxide, 2-methoxyethanol, H2O and HCl is 0.7 : 0.3 : 5.25 : 20 : 3.6 x 10(-4), the specific surface area of the particles was 260 m(2)/g. After the extraction of SiO2 parts by 1 M NaOH aqueous solution, the weight loss of the particle was 10 mass%. Titania particles are obtained by addition of diethanolamine or 2-methoxyethanol in starting solution, Peak pore-diameter of the particles is 4 nm when the molar ratio of diethanolamine to titanium tetraisopropoxide was 1.5, By calcination at 500 and 700 degrees C, the particle occurred anatase and rutile type, respectively. TiO2-SiO2 binary particles are synthesized by using 2-methoxyethanol, When the molar ratio of titanium tetraisopropoxide, TMOS, 2-methoxyethanol, H2O and HCl is 0.4 : 0.6 : 4 : 20 : 1.8 x 10(-3), the specific surface area of the particles was 180 m(2)/g after the extraction of SiO2 parts by 0.1 M NaOH aqueous solution.

DOI： 10.2109/jcersj.106.1184

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Language：English   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

The Sn4+ - Sn2+ equilibrium in binary sodium borate melts was studied by means of differential pulse voltammetry. The half-wave potentials in the reduction of Sn4+ to Sn2+ shift to the negative with an increase in Na2O content and a decrease in temperature. These results indicate that the population of Sn4+ increases with an increase in basicity. A linear relation between log r(r= [Sn2+]/[Sn4+]) and optical basicities was observed. Log r was also found to depend linearly on thermodynamic basicity, such as -log alpha(Na2O) where alpha(Na2O) denotes the activity of Na2O in melts.

DOI： 10.2109/jcersj.106.724

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The Si-29 and P-31 nuclear magnetic resonance (NMR) chemical shifts and the Q(n) distribution in ternary sodium phosphosilicate glasses were examined. In the NaPO3-SiO2 glasses, only the Si(Q(4)) unit from SiO2 and the P(Q(2)) unit from NaPO3 are observed. When the P2O5 content increases at fixed mole fractions of SiO2 equal to 0.1 and 0.05, the 6-coordinated silicon atoms appear. The presence of 6-coordinated silicon atoms is expected in glasses where the [P2O5]/[Na2O] composition ratio is greater than unity. Their appearances can be understood in terms of the relative acidic strength of SiO2 and P2O5. The profile of Raman spectra changes appreciably due to the formation of 6-coordinated silicon atoms.

DOI： 10.2109/jcersj.106.539

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Language：Japanese   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

The structure anal electronic states of Na2S-SiO2 oxysulfide glasses were investigated and the role of sulfur in the glasses is discussed. Na2S formed stable glass with SiO2 at an alkali concentration range similar to that of Na2O-SiO2 systems by the conventional melt-quench method. The obtained glasses were reddish brown in color and a remaining of sulfur was confirmed. X-ray photoelectron spectroscopy (XPS) was used to study the chemical bonding state of bridging and nonbridging anionic species in Na2S-SiO2 glass. The S2p binding energy of the glass was observed to be approximately 161 eV, This value is lower than that of orthorhombic crystalline sulfur and almost the same as the value of Na2S. From the results, the electron density around sulfur was near to that of S2-. Furthermore, by Si-29 magic angle spinning (MAS) and nuclear magnetic resonance (NMR) measurement, three clear-cut peal-rs were detected between 0 and -120 ppm. It was assumed that a sulfur atom was joined to silicon via substitution for an oxygen atom, and was present as nonbridging sulfur in Na2S-SiO2, glass with low alkali ion concentration. On the other hand, it was revealed that a portion of the sulfur ions existed in an isolated state from the glass-network structure at high alkali content. The glass composition changed to a chemical composition that was more silica rich than predicted. The sulfur ions made sulfide clusters with the sodium ions isolated from the glass-network.

DOI： 10.2109/jcersj.106.150

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DOI： 10.1016/S0022-3093(97)00442-0

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DOI： 10.1016/S0022-3093(97)00442-0

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Language：English   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Porous silica glass was prepared by phase separation of sodium borosilicate glass. The distributions of SiO4 structural units, Q(n), were examined by Si-29 magic-angle spinning (MAS) NMR after each process in a series of acid and thermal treatments. The NMR spectra reveal three distinct peaks due to the presence of a silanol group on the surface of the porous silica glass. However, only a single peak around -110 ppm that originated from a Q(4) unit which lacked any OH groups could be observed after heat treatment at 900 degrees C.

DOI： 10.2109/jcersj.105.700

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Language：Japanese   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Spherical porous silica particles were synthesized by the sol-gel process from tetramethoxysilane and methyltrimethoxysilane in W/O emulsion. The difference in structure change by calcination is remarkable between air and nitrogen atmospheres. By calcination of the particles under N-2 gas atmosphere their pore structures can be maintained up to 1000 degrees C. This is due to the fact that Si-CH3 bond remains at high temperature. The Si-29 MAS NMR spectra revealed that the intensity of T-3 structural unit, whose origin is Si-C bonding,increased with an increase in methyltrimethoxysilane in a starting solution.

DOI： 10.2109/jcersj.105.335

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Language：English   Publisher：ELSEVIER SCIENCE BV  

An electrochemical study of antimony ions doped in sodium borate and silicate glass melts was investigated by differential pulse voltammetry at various temperatures, by which Sb5+-Sb3+ redox reactions were observed. The half wave potentials for reduction of Sb5+ to Sb3+ shifted toward negative values with increasing Na2O content of the glass-forming liquids and with decreasing temperature. Substitution of Na2O by CaO in sodium silicate liquids shifted the half wave potential to the positive side. These results correspond to an increase of the content of pentavalent antimony ions with an increase of the basicity of the glass-forming liquids.

DOI： 10.1016/0022-3093(96)00190-1

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Language：English   Publisher：JAPAN SOC ANALYTICAL CHEMISTRY  

Dispersed porous spherical silica particles were prepared by a sol-gel process from solutions of tetramethoxysilane (TMOS), polyethyleneglycol (PEG), H2O and organic solvent in W/O (water in oil phase) emulsions. The interconnected pores can be made by eliminating PEG from gel bodies. Such PEG originates by phase separation between the PEG and the polymerizing silica in common solvents. Microstructures of the particles are affected by the compositions of the starting solutions. The pore diameter increases with an increase in molecular weight of PEG when the molar ratio of PEG as monomer unit to TMOS is fixed to 0.3. The pore diameter decreases and specific surface area increases with an increase in the content of PEG having molecular weight of 50000 when the [PEG]/[TMOS] molar ratio is greater than 0.3. The pore diameter decreases by use of basic solvents such as N,N-dimethylformamide (DMF) and formamide (FA) instead of methanol.

DOI： 10.2116/analsci.10.737

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DOI： 10.2109/jcersj.102.419

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Language：English   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)   Publisher：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Spherical porous silica glasses whose average diameter is 40 mum are synthesized by the sol-gel process in W/O emulsions and a successive thermal treatment. The interconnected pore structure was seen in the particles. The pore size can be controlled by changing temperature of thermal treatment. The presence of residual carbons can be avoided by decreasing unreacted alkoxides with increasing water content of the initial solution in the sol-gel process.

DOI： 10.2109/jcersj.101.1180

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Language：English   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

The optical resolutions of amino acids and mandelic acid (MA) are done by complexation with copper(II). The optical purity of MA is the best when phenylalanine is used, i.e. 81%, and phenylglycine (PG) is well resolved by using L-MA with the optical purity of 74%. These results are interpreted in terms of the optical absorption energies of the copper(II) complexes in aqueous solution.

DOI： 10.1246/bcsj.66.2764

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DOI： 10.1246/bcsj.66.2764

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DOI： 10.2116/bunsekikagaku.42.12_811

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DOI： 10.2109/jcersj.101.500

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DOI： 10.2116/analsci.9.545

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DOI： 10.2116/analsci.9.545

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Language：English   Publisher：CHEMICAL SOC JAPAN  

The optical resolutions of phenylalanine and mandelic acid were performed by complex formation with Cu2+. D- and L-mandelic acids were completely resolved by forming a complex with L-phenylalanine, while the maximum optical purity of D- and L-phenylalanine by using D-mandelic acid was about 65%. The mole ratio of Cu2+ to phenylalanine and/or mandelic acid in the complexes was 0.5. These results were interpreted in terms of the relative stability of the complexes, i.e., the optical absorption energies in the aqueous media.

DOI： 10.1246/bcsj.65.3149

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Language：English   Publisher：JAPAN SOC ANALYTICAL CHEM  

The ion flotation of rare-earth and another fifteen metal ions was investigated using octadecyliminobismethylenebisphosphonic acid (OIMBP) as an anionic surfactant having the ability to form complexes with metal ions. The efficiency of flotation was greater than that with dodecyliminobismethylenebisphosphonic acid (DIMBP) due to its low pK(a1) value, as well as the hydrophobic property of the alkyl chain of OIMBP. The rare-earth ions were classified into three groups according to their flotation behavior. A successive flotation procedure used to separate rare-earth ions was then proposed.

DOI： 10.2116/analsci.8.247

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Language：English   Publisher：JAPAN SOC ANALYTICAL CHEM  

The flotation of metal ions was investigated using diphenyl- and diethyl dithiophosphoric acids. From their flotation behavior, the metal ions were classified into three groups. The ions of first group [Au(III), Pd(II), Sb(III), In(III), Cd(II), Bi(III), Cu(II) and Pb(II)] floated effectively under acidic conditions. The maximum yields of the ions of second group [Zn(II), Co(II) and Ni(II)] appeared at around pH = 10. On the other hand, the floatability of ions belonging to the third group [Fe(III), Ga(III), Cr(III), Cr(VI), Ti(TV), Hf(IV), Al(III) and U(VI)] was lower than those of the first and second groups. These results could be fairly well understood in terms of HSAB (hard and soft acids and bases) prediction.

DOI： 10.2116/analsci.8.251

Web of Science

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Language：Japanese   Publisher：The Ceramic Society of Japan  

Silica-gel particles were synthesized by the sol-gel method in W/O emulsion. Preparation conditions were studied for controlling the particle diameter of the silica-gel, i.e., reaction temperature, agitation speed, the value of hydrophile-lipophile-balance of surfactants, and the nature of reaction vessel. Properties of the silica-gel were determined by the scanning electron microscopic method, particle diameter distribution, specific surface area, and pore size distribution. The particle diameter of the silica-gel was about 5-15 μm. The silica-gel was applied to packing materials for high-performance liquid chromatography (HPLC) after modifying the surface of the silica-gel with octadecyl group. The amino acids and aromatic compounds were successfully separated and the quantitative analysis of phenylalanine could thoroughly be performed.

DOI： 10.2109/jcersj.100.1444

CiNii Books

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Other Link： https://jlc.jst.go.jp/DN/JALC/00370907725?from=CiNii

Language：English   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)   Publisher：CHEMICAL SOC JAPAN  

From the polarographic behavior of copper (II), lead(II), cadmium(II), and manganese(II) in aqueous glycine solutions at an ionic strength of 0.4 mol dm-3 adjusted with sodium perchorate, the species of the metal complexes and their stability constants were determined.

DOI： 10.1246/bcsj.64.697

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DOI： 10.1246/nikkashi.1991.168

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Language：English   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)   Publisher：JAPAN SOC ANALYTICAL CHEMISTRY  

DOI： 10.2116/analsci.6.783

Web of Science

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DOI： 10.1246/nikkashi.1990.119

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DOI： 10.1246/nikkashi.1989.697

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DOI： 10.2116/bunsekikagaku.38.21

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DOI： 10.1246/nikkashi.1989.2035

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DOI： 10.2116/bunsekikagaku.38.10_537

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DOI： 10.1246/nikkashi.1989.1859

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DOI： 10.1246/nikkashi.1988.1017

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DOI： 10.11457/swsj1965.42.186

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DOI： 10.2116/bunsekikagaku.36.12_825

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DOI： 10.2116/bunsekikagaku.36.6_386

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DOI： 10.1246/nikkashi.1987.827

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DOI： 10.2116/bunsekikagaku.35.12_977

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Language：Japanese   Publisher：The Society of Sea Water Science, Japan  

A method has been developed for the concentration of uranium in seawater by precipitation flotation-carbonate extraction-ion flotation. Uranium in seawater was coprecipitated with hydrated iron (III) oxide by adjusting the pH to 5.5 after addition of 1.0×10<SUP>-3</SUP>mol/<I>l</I> of iron (III) and agitating for 1hr, and the precipitate was floated with 1.0×10<SUP>-5</SUP>mol/<I>l</I> of sodium oleate and 5.0×10<SUP>-5</SUP>mol/<I>l</I> of sodium lauryl sulfate by bubbling nitrogen through the seawater for 15min. Uranium was extracted from the precipitate scum at the yield of 89% with 100ml of 1.8% of ammonium carbonate solution by agitating for 2hr, and floated with 1.2×10<SUP>-3</SUP>mol/<I>l</I> of cetylpyridinium chloride by bubbling nitrogen through the extract diluted 5-fold for 30 min in the recovery of about 100%. The fairly selective recovery of uranium was obtained from 4<I>l</I> of seawater at the yield of 87% throughout the entire process.

DOI： 10.11457/swsj1965.40.95

CiNii Books

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Other Link： https://jlc.jst.go.jp/DN/JALC/10016679695?from=CiNii

Faculty of Engineering / Specialized Subjects

Graduate School of Science and Engineering(Master Course)

Faculty of Engineering / Specialized Subjects

Faculty of Engineering / Specialized Subjects

Graduate School of Science and Engineering(Master Course)

Graduate School of Science and Engineering(Master Course)

Faculty of Engineering / Specialized Subjects