研究者詳細 - 難波　徳郎

論文 - 難波　徳郎

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Intensified photoluminescence of EU3+ in the phase-separated borosilicate glass 査読

Z Yao, Y Ding, T Nanba, Y Miura

JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 106 ( 11 ) 1043 - 1047 1998年11月

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

Eu3+ containing 3Na(2)O . 42B(2)O(3). 55SiO(2) (mol%) glass was isothermally heat-treated for phase separation. The photoluminescence (PL) behavior of Eu3+ was investigated. It was found that PL intensity of D-5(0)-->F-7(2) transition of Eu3+ increases with evolution of phase separation. A maximum 6.5 times increment in the PL intensity can be obtained after phase separation as compared to that of the as-cast sample. Moreover, the maximum increment of the PL intensity seems to be related to the texture induced by phase separation, the droplet texture being superior to the interconnected one. The mechanism of augmentation of the PL intensity was interpreted in terms of the derived expression of the PL intensity. It was then suggested that the induced interface after phase separation, causing remarkable increase in light scattering intensity and therefore notable increase in the population of Eu3+ On the D-5(0) energy level, accounted for significant enhancement in the PL intensity. On the other hand, from the emission intensity ratio of D-5(0)-->F-7(2) to D-5(0)-F-7(1) transitions of Eu3+, it was estimated that Eu3+ partitioned into the berate-rich phase after phase separation.

DOI： 10.2109/jcersj.106.1043

Photoluminescence characteristics of Eu3+ doped in phase separated borosilicate glass 査読

ZD Yao, Y Ding, T Nanba, Y Miura

MATERIALS SCIENCE RESEARCH INTERNATIONAL 4 ( 3 ) 141 - 147 1998年9月

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

The 6NaO.31B(2)O(3).63SiO(2) (in mot%) glass was chosen. The photoluminescence(PL) characteristics of Eu3+ doped in the glass, which was subjected to different phase separated heat treatments, were investigated systematically, It was found that PL intensity of D-5(0)-->F-7(2) transition of Eu3+ increased with phase separation developing, Furthermore, the maximum PL intensities obtained by the different heat treatment processes seem to depend on the morphology induced by phase separation, the droplet morphology having the advantage over the interconnected one with the PL intensities of 6.4 and 5.5 times as high as that in the as-cast sample, respectively. The mechanism of enhancement of the PL intensity was then discussed on the basis of the derived expression of the PL intensity. It was concluded that the induced interface after phase separation, engendering significant increase in light scattering intensity and thereby notable increase in the population of Eu3+ on the D-5(0) energy level, accounted for considerable increase in the PL intensity. On the other hand, from the emission intensity ratio of the D-5(0)-->F-7(2) to D-5(0)-->F-7(1) transitions (R) of Eu3+, the phases into which Eu3+ segregated after various phase separation processes were estimated.

アルカリケイ酸塩ガラスのX線光電子スペクトル査読

松本修治, 難波徳郎, 三浦嘉也

日本セラミックス協会学術論文誌 106 ( 4 ) 415 - 421 1998年4月

Na_2S-SiO_2系ガラス中の硫黄の状態分析

朝日太郎, 伊野隆之, 三浦嘉也, 難波徳郎, 山下浩

日本セラミックス協会学術論文誌 : Nippon Seramikkusu Kyokai gakujutsu ronbunshi 106 ( 1230 ) 150 - 154 1998年2月

記述言語：日本語出版者・発行元：公益社団法人日本セラミックス協会

The structure and electronic states of Na_2S-SiO_2 oxysulfide glasses were investigated and the role of sulfur in the glasses is discussed. Na_2S formed stable glass with SiO_2 at an alkali concentration range similar to that of Na_2O-SiO_2 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 Na_2S-SiO_2 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 Na_2S. From the results, the electron density around sulfur was near to that of S^<2->. Furthermore, by ^<29>Si magic angle spinning(MAS)and unclear magnetic resonance(NMR)measurement, three clear-cut peaks 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 Na_2S-SiO_2 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

その他リンク： https://jlc.jst.go.jp/DN/JALC/00370920953?from=CiNii

Na2S-SiO2系ガラス中の硫黄の状態分析査読

朝日太郎, 伊野隆之, 三浦嘉也, 難波徳郎, 山下浩

日本セラミックス協会学術論文誌 106 ( 2 ) 150 - 154 1998年2月

Wavelet analysis of x-ray diffraction pattern glass structures 査読

Yong Ding, Tokuro Nanba, Yoshinari Miura

Physical Review B 58 ( 21 ) 14279 - 14287 1998年

Frequency doubling in gallium-lanthanum-sulphide glass with surface crystallized Ga6La10/3S14 thin films 査読

Yong Ding, Atsuhiro Kondoh, Yoshinari Miura, Tokuro Nanba

Applied Physics Letters 73 ( 6 ) 738 - 740 1998年

担当区分：最終著者記述言語：英語掲載種別：研究論文（学術雑誌）

The reason for the optical frequency doubling in the 70Ga2S3-30La2S3 glass is investigated. The tetragonal Ga6La10/3S14 phase due to crystallization of the glass is responsible for the frequency doubling. Dense and transparent Ga6La10/3S14 crystalline thin films have been prepared by means of the controlled surface treatment of the glass due to an ultrasonic surface treatment. The effective second-order nonlinear optical susceptibilities of the crystalline thin films are analyzed. © 1998 American Institute of Physics.

DOI： 10.1063/1.121985

Wavelet structural analysis of silica glasses manufactured by different methods 査読

Y Ding, T Nanba, Y Miura, A Osaka

JOURNAL OF NON-CRYSTALLINE SOLIDS 222 50 - 58 1997年12月

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

Wavelet analysis of X-ray diffraction patterns was made for structures of silica glasses manufactured by electrical fusion, oxy-hydrogen flame fusion of quartz powder, and flame hydrolysis of SiCl4. The analysis indicates that their structures were not affected by the manufacture methods. It is believed that there is a thermodynamically most favoured or unique structure for glass in an intermediate range up to a few nm. It is expected that amorphography (in analogy to crystallography for crystal) for glass will emerge as a new branch of science. According to our statistical crystallite model, glass structure could be determined by the crystallography of corresponding crystals and the damping with interatomic distance for the crystalline regularity. (C) 1997 Elsevier Science B.V.

ZrO_2分散MgO-Al_2O_3系セラミックスの作製とその性質(第3報) : MgO/Al_2O_3組成比の影響

坪井宏之, 吉松英之, 難波徳郎, 三浦嘉也

日本セラミックス協会学術論文誌 : Nippon Seramikkusu Kyokai gakujutsu ronbunshi 105 ( 1223 ) 588 - 594 1997年7月

記述言語：日本語出版者・発行元：公益社団法人日本セラミックス協会

ZrO_2-dispersed MgO-Al_2O_3 ceramics with various MgO to Al_2O_3 compositional ratios were prepared from Mg(OH)_2 powder, α-Al_2O_3 powder and Zr-n-butoxide by calcining at 1000°C for 2h and sintering at 1600°C for 1h. The influence of the MgO-Al_2O_3 compositional ratio on the sinterability and mechanical properties was studied. Addition of 10 vol% ZrO_2 improved the relative density of the sintered specimens containing 50 and 62.5 mol% Al_2O_3. However, the addition was not effective at other compositional ratios. The bending strength was improved at composition containing more than 50 mol% Al_2O_3, Where the dispersed ZrO_2 Particles were in the form of tetragonal phase. The bending strength increased with increase in Al_2O_3 content in the ZrO_2 dispersed specimens. The fracture toughness was improved for all specimens by ZrO_2 dispersion, especially, for the specimen in which MgO-Al_2O_3 component was in a single crystalline phase.

DOI： 10.2109/jcersj.105.588

その他リンク： https://jlc.jst.go.jp/DN/JALC/00370919452?from=CiNii

Preparation and properties of the ZrO2-dispersed MgO-Al2O3 ceramics .3. Influence of MgO-Al2O3 composition 査読

H Tsuboi, H Yoshimatsu, T Nanba, Y Miura

JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 105 ( 7 ) 588 - 594 1997年7月

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：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI

ZrO2-dispersed MgO-Al2O3 ceramics with various MgO to Al2O3 compositional ratios were prepared from Mg(OH)(2) powder, alpha Al2O3 powder and Zr-n-butoxide by calcining at 1000 degrees C for 2h and sintering at 1600 degrees C for 1h. The influence of the MgO-Al2O3 compositional ratio on the sinterability and mechanical properties was studied. Addition of 10 vol% ZrO2 improved the relative density of the sintered specimens containing 50 and 62.5 mol% Al2O3. However, the addition tvas not effective at other compositional ratios. The bending strength was improved at composition containing more than 50 mol% Al2O3, where the dispersed ZrO2 particles were in the form of tetragonal phase. The bending strength increased with increase in Al2O3 content in the ZrO2 dispersed specimens. The fracture toughness was improved for all specimens by ZrO2 dispersion, especially, for the specimen in which MgO-Al2O3 component was in a single crystalline phase.

DOI： 10.2109/jcersj.105.588

Photochromic properties in cadmium bismuth aluminate glasses and its oxidation treatment effect 査読

DP Chen, Y Miura, Y Murata, T Nanba, A Osaka

JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 105 ( 4 ) 322 - 328 1997年4月

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

Photochromic properties were investigated for glass in the system CdO-Bi2O3-Al2O3. Optical density increased with increasing BiO1.5 content in the glasses at fixed CdO content. The darkening degree could be effectively enhanced by oxidation treatments. The composition dependence and effect of oxidation treatment were studied by X-ray photoelectron and Raman scattering spectroscopies. With increasing BiO1.5 content the Lewis basicity of oxygen atoms increased and the fraction of covalently bonded cadmium decreased. The trap density of holes increased and the photogeneration yield decreased. The darkening degree showed a maximum around BiO1.5=13 cation%. The effect of oxidation treatment on the darkening degree may be related to production of a large amount of monovalent O- ions with holes in their 2p valence band, and to formation of electron centers in cadmium atoms.

DOI： 10.2109/jcersj.105.322

X-ray photoclectron spectroscopy of alkali tellurite glasses 査読

Y. Himei, Y. Miura, T. Nanba, A. Osaka

Journal of Non-Crystalline Solids 211 ( 1-2 ) 64 - 71 1997年

Photochromic properties in cadmium bismuth aluminate glasses and its oxidation treatment effect

Danping Chen, Yoshinari Miura, Yasuaki Murata, Tokuro Nanba, Akiyoshi Osaka

Journal of the Ceramic Society of Japan 105 ( 4 ) 322 - 328 1997年

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

Photochromic properties were investigated for glass in the system CdO-Bi2O3-Al2O3. Optical density increased with increasing BiO1.5 content in the glasses at fixed CdO content. The darkening degree could be effectively enhanced by oxidation treatments. The composition dependence and effect of oxidation treatment were studied by X-ray photoelectron and Raman scattering spectroscopies. With increasing BiO1.5 content the Lewis basicity of oxygen atoms increased and the fraction of covalently bonded cadmium decreased. The trap density of holes increased and the photogeneration yield decreased. The darkening degree showed a maximum around BiO1.5=13 cation%. The effect of oxidation treatment on the darkening degree may be related to production of a large amount of monovalent O- ions with holes in their 2p valence band, and to formation of electron centers in cadmium atoms.

Bi_2O_3-CdO-Al_2O_3系ガラスおよびガラスセラミックスの着色に関する研究(<特集>セラミックス)

陳丹平, 三浦嘉也, 難波徳郎, 村田泰章, 尾坂明義

材料 45 ( 6 ) 630 - 636 1996年6月

記述言語：日本語出版者・発行元：社団法人日本材料学会

Color change and its mechanisms for glasses and glass-ceramics in the Bi_2O_3-CdO-Al_2O_3 system prepared under various melting and annealing conditions were investigated. It was suggested that brown color of the glasses with comparatively low Bi content which were obtained by melting at high temperatures was caused by metallic Bi while deep green color of the glasses with comparatively high Bi content resulted from Bi^<2+> and defects. The deep color of the glasses markedly faded after annealing treatments for long time. Formation of the transparent glass-ceramics was assumed to be related to the oxygen defects. Color of the glass-ceramics was explained in term of oxygen defects and crystalline phases formed by annealing treatments.

DOI： 10.2472/jsms.45.630

その他リンク： https://jlc.jst.go.jp/DN/JALC/00040381626?from=CiNii

Thermochromism and temperature dependence of the energy gap in cadmium aluminum bismuthate glasses 査読

DP Chen, Y Miura, T Nanba, A Osaka

JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 104 ( 2 ) 79 - 83 1996年2月

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

Reversible thermochromic coloration was detected in Bi0(1.5)-CdO-AlO1.5 system glasses. The relevant parameters were strongly dependent on the BiO1.5 content. It was suggested that the weakened and more polarized Bi-O bond due to increased BiO1.5 content enhanced the thermochromism of the glasses. The redshift of absorption edges at room temperature and the increase in the temperature coefficient of the shift with increasing BiO1.5 content were analyzed. The thermochromic mechanism was explained in terms of the temperature dependence of the optical energy gap caused mainly by electron-phonon interaction.

DOI： 10.2109/jcersj.104.79

X-RAY-DIFFRACTION STUDY ON THE FRAMEWORK STRUCTURE OF AMORPHOUS TUNGSTEN TRIOXIDE FILMS 査読

T NANBA, T TAKAHASHI, S TAKANO, J TAKADA, A OSAKA, Y MIURA, T KUDO, YASUI, I

JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 103 ( 3 ) 222 - 229 1995年3月

担当区分：筆頭著者,　責任著者記述言語：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

Amorphous tungsten trioxide films were prepared from iso-polytungstic acid as a precursor and by RF magnetron sputtering method. Framework structure was investigated based on X-ray diffraction analyses, in which amplitude function as well as radial distribution function was used, And the previously reported films prepared by vacuum evaporation and an ion exchange method using Na2WO4 . 2H(2)O as a precursor were also re-examined. It was found that, in the films derived from iso-polytungstic acid, the framework had a similar manner to that in hexagonal-WO3 crystal, whose framework was constructed by 3-, 4- and 6-membered rings formed by WO6 octahedra. It was supposed that edge-sharing polyhedra and tungsten and/or WO6 defects were present in the as-prepared film and changed to corner-sharing connection and continuous framework by post-annealing. It was also suggested that structural water was present in a hexagonal tunnel in the framework. These structural characteristics were also observed in the films prepared by vacuum evaporation and ion exchange methods. As for the sputtered films, formation of two framework-types without structural water was confirmed. The hexagonal-WO3 like framework was formed in the films prepared under a low O-2 partial pressure, and tetragonal-WO3 like one with an ordinary ReO3-type structure made up with 4-membered rings was produced at a high O-2 pressure.

DOI： 10.2109/jcersj.103.222

X-ray diffraction study on the framework structure of amorphous tungsten trioxide films

Tokuro Nanba, Tadashi Takahashi, Sanae Takano, Jun Takada, Akiyoshi Osaka, Yoshinari Miura, Tetsuichi Kudo, Itaru Yasui

Journal of the Ceramic Society of Japan. International ed. 103 ( 3 ) 224 - 232 1995年3月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Fuji Marketing Research Co Ltd

A-WO3 films have been synthesized from an isolated polytungstic acid as a precursor and by RF magnetron sputtering. Framework structure of the a-WO films is also re-investigated in detail based on X-ray diffraction analyses, from which some new structural information are obtained, such as the formation of novel frameworks and the defect structure of the framework.

STRUCTURE OF 50NA(2)O.XAL(2)O(3).(50-X)P2O5 AND (50-X/2)NA2O.XAL(2)O(3).(50-X/2)P2O5 GLASSES

INOUE, H, MAKISHIMA, A, KANAZAWA, T, NANBA, T, YASUI, I

Physics and Chemistry of Glasses 36 ( 1 ) 1995年

Characterization of amorphous tungsten trioxide thin films prepared by rf magnetron sputtering method 査読

Tokuro Nanba, Tadashi Takahashi, Jun Takada, Akiyoshi Osaka, Yoshinari Miura, Itaru Yasui, Akira Kishimoto, Tetsuichi Kudo

Journal of Non-Crystalline Solids 178 ( C ) 233 - 237 1994年11月

担当区分：筆頭著者,　責任著者記述言語：英語掲載種別：研究論文（学術雑誌）

Amorphous tungsten trioxide thin films were prepared using a rf magnetron sputtering method. The relation between structure and electrochromic properties was investigated. At the macroscopic level, the films had dense structures. From Raman spectroscopic and X-ray radial distribution analyses, it was deduced that the networks were basically formed by three-, four- and six-membered rings of corner-sharing WO6 octahedra, and in the films with low O/W atomic ratios many edge-sharing units were present. It was also found that the films with high O/W ratios showed good electrochromic properties, which were closely related to the six-membered rings. © 1994.

DOI： 10.1016/0022-3093(94)90290-9

Computer simulation on the structure and vibrational spectra in GePbOF glass 査読

Tokuro Nanba, Takahiro Miyaji, Jun Takada, Akiyoshi Osaka, Yoshinari Miura, Itaru Yasui

Journal of Non-Crystalline Solids 177 ( C ) 131 - 136 1994年11月

担当区分：筆頭著者,　責任著者記述言語：英語掲載種別：研究論文（学術雑誌）

Oxy-fluoride glasses in the GeO2PbOPbF2 system were prepared and their structure investigated using vibrational spectra, X-ray diffraction and Raman spectra methods. Structural models were constructed by molecular dynamics simulations. In the models obtained, glass networks were formed by GeO4 tetrahedra and Ge(O,F)5 and Ge(O,F)6 polyhedra. Lead entered the networks at PbFPb in the models with high Pb/Ge ratio. The presence of germanium with high coordination numbers of 5 and 6 was supported by radial distribution analyses. GeO bonds in GeO4 tetrahedra seemed to give bands between 650 and 850 cm-1 (non-bridging oxygen) and between 450 and 650, and between 850 and 950 cm-1 (bridging oxygen). GeO and GeF in Ge(O,F)n (n &gt
4) were supposed to contribute the bands observed between 350 and 550 cm-1 in the Raman spectra. © 1994.

DOI： 10.1016/0022-3093(94)90522-3

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