巻号一覧
39 巻, 5 号
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一ノ瀬 昇1992 年 39 巻 5 号 p. 332
発行日: 1992/05/15
公開日: 2009/05/22
ジャーナル フリーPDF形式でダウンロード (73K) -
高田 潤1992 年 39 巻 5 号 p. 333-336
発行日: 1992/05/15
公開日: 2009/05/22
ジャーナル フリーThe addition effects of Pb, Ba and Li to the 2223 phase in the Bi-Sr-Ca-Cu-O system on the properties and the formation process have been reviewed.The incorporation of Pb and Ba into the 2223 phase and the increase in Tc has been experimentally discussed.The substitution sites of the elements have been interpreted on the basis of the results of the equilibrium phase diagrams for the 2201 phase reported so far.The formation process of the Pb and Pb+Ba doped 2223 phase has also been discussed with particular attention to liquid formation and wettability.抄録全体を表示PDF形式でダウンロード (229K) -
東 正樹, 広井 善二, 高野 幹夫, 坂東 尚周, 武田 保雄, 山本 治, 大高 理, 久米 昭一, 山中 高光1992 年 39 巻 5 号 p. 337-340
発行日: 1992/05/15
公開日: 2009/05/22
ジャーナル フリーCupric oxide superconductors are made of 2D CuO2 sheets and 2D counter sheets stacked alternatively along a crystallographic axis. These sheets match their 2D lattices through intersheet metal-oxygen bonding. Because the Cu-O and counter cation-O bonds should have different compressibilities and different thermal expansion coefficients, it is quite reasonable to assume that preparation in various pressure-temperature regions give us new materials having new structures and/or new compositions.
We found previously that the so-called infinite layer structure could be stabilized at high pressure (6GPa) for a much wider alkaline earth composition range including SrCuO2 than at ambient pressure. Fortunately we recently found a superconductor with Tc-110 K having an alkaline earth deficient composition (Sr, Ca)1-xCuO2 (x-0.1).抄録全体を表示PDF形式でダウンロード (1311K) -
鄂 剛, 吉川 信一, 金丸 文一, 宮本 欽生, 吉岡 秀樹, 元山 宗之1992 年 39 巻 5 号 p. 341-344
発行日: 1992/05/15
公開日: 2009/05/22
ジャーナル フリーA new superconductor Sr1-xLaxCuO2, having an infinite-layer structure was prepared in a reductive atmosphere applying high pressure synthesis. Its solid solution limit was around X=0.12. The Tc(onset) value was 43K independently on X and the volume fraction of the superconductor showed a maximum at X=0.10. Positive value was observed on a Hall effect measurement on the sample with X=0.10 in a temperature range above 77K.抄録全体を表示PDF形式でダウンロード (215K) -
武田 保雄, 橋本 裕司, 佐藤 敦, 今西 誠之, 山本 治1992 年 39 巻 5 号 p. 345-348
発行日: 1992/05/15
公開日: 2009/05/22
ジャーナル フリーWe report the preparation, structure and electrical properties of LaNiO3-z, PrNiO23-z and LaCuO3-x. Wide range of oxygen deficiency was realized by changing the synthetic oxygen pressure. These systems show metallic conductivity even for the samples having a large amount of oxygen vacancy (Z<0.25). The Seebeck coefficient measurement showed that the dominant carrier in LnNiO3-z system is electron, while hole carrier is dominant in LaCuO3-z system.抄録全体を表示PDF形式でダウンロード (189K) -
勝山 茂, 真島 一彦, 永井 宏, 小菅 皓二1992 年 39 巻 5 号 p. 349-352
発行日: 1992/05/15
公開日: 2009/05/22
ジャーナル フリーThe magnetic hysteresis curve of YBa2(Cu1-xFex)3Oy(0≤x≤0.08) prepared by two kinds of heat treatments was measured by SQUID magnetometer. YBa2(Cu1-xFex)3Oy was slowly cooled from 890°C in air, and a part of the samples was heated at 800°C in N2 gas. All products including those heated in N2 gas were annealed below 400°C in O2 gas. The measurements by SQUID were done at 5K and in magnetic fields up to 1T. Δ M, the difference in the hysteretic magnetization between the increasing and decreasing magnetic fields, of the samples prepared by heating in N2 gas followed by annealing in O2 gas shows the maximum value at x=0.02. This seems to indicate that the clustering of Fe atoms in the Cu1-O planes of the sample acts as effective pinning centers for flux lines.抄録全体を表示PDF形式でダウンロード (213K) -
垣花 眞人, 吉村 昌弘, 間崎 啓匡, 安岡 宏1992 年 39 巻 5 号 p. 353-357
発行日: 1992/05/15
公開日: 2009/05/22
ジャーナル フリーSuperconducting Y1-xCaxBa2Cu4Oy ceramics with x=0, 0.05 and 0.1 have been synthesized by the polymerized complex method, which includes three important major steps: (1) formation of metalcitrate complexes dispersed into ethyleneglycol and water, (2) fabrication of polymerized complexes formed through esterification between ethyleneglycol and metal-citrate complexes and (3) pyrolysis of the polymerized complex precursor. The main advantages of the present technique are the elimination of centrifugation, ageing and fine control of pH usually required for other solution techniques. Complex magnetic susceptibility measurements for YBa2Cu4Oy (Y124) prepared under one atmospheric oxygen pressure have revealed a progress in homogeneity and superconducting properties compared to those of samples prepared by the other techniques. Better superconducting properties have been achieved for the parent Y124 when the sample was additionally treated with a high oxygen pressure (post O2-HIP). The post O2-HIP treatment is probably essential for producing Ca-doped Y124 in its pure form. Tc is increased from 81.3K for x=0.0 to 86.7K for x=0.05.However, further increase in Ca content results in partial decomposition of the sample into Y124, Y247 and other unknown impurities under the present HIP condition. The increase in Tc with increasing Ca content would be attributable to an inrease in hole concentration owing to the substitution of the divalent Ca ion for the trivalent Y ion.抄録全体を表示PDF形式でダウンロード (316K) -
長谷井 政治, 黒沢 秀行, 山根 久典, 平井 敏雄1992 年 39 巻 5 号 p. 358-361
発行日: 1992/05/15
公開日: 2010/07/12
ジャーナル フリーBi-Sr-Ca-Cu-O superconducting films were prepared on MgO (100) substrates by chemical vapor deposition using triphenyl bismuth and β-diketonates of Sr. Ca and Cu as source materials. The films composed of c-axis oriented 30 Å and 37 Å phases were prepared at 800°C. The films with indicating of the highest XRD intensity of the 37 Å phase exhibited a Bi:Sr:Ca:Cu molar ratio of around 2:2:3:4. Increase of oxygen partial pressure during film deposition at deposition rate of 0.2μm/h raised values of α which is the XRD intensity ratio of 37 Å phase as compared with 30 Å phase. However, values of α for the films prepared at a deposition rate of 0.1μm/h were around 0.7 and did not depend on the oxygen partial pressure from 2.5 to 60 Torr. At a deposition temperature of 800°C, the film having the highest value of the XRD intensity ratio of 37 Å phase was obtained. At deposition temperatures of 830-850°C, the 24 Å phase appeared with the 30 Å and 37 Å Phases. The onset temperature of superconducting transition was observed at around 110 K for the films containing the 37 Å phase. However, the films prepared at 800°C showed Tc (resistivity zero: R=0) at 65 K. The highest Tc (R=0) of 74 K was measured for the film prepared at 850°C.抄録全体を表示PDF形式でダウンロード (1794K) -
佐野 恭司, 池田 靖訓, Than Min Kyaw, 広井 善二, 高野 幹夫, 坂東 尚周1992 年 39 巻 5 号 p. 362-365
発行日: 1992/05/15
公開日: 2009/12/04
ジャーナル フリーWe studied the effects of adding Ca to the Bi2+xSr2-xCu1+x/4Oz solid solution. It turned out that the Ca ions substitute for Sr. Monopasic compositions of Bi2+xSr2-x-yCayCu1+x/4 with 0.1<x<0.6 and 0<y<0.6 were obtaind. In the Ca-containing solid solution. The specimen of Bi2.1Sr1.8⋅Ca0.1Cu1.025Oz showed superconductivity at 7.8K. But the others were semiconductive.抄録全体を表示PDF形式でダウンロード (223K) -
間崎 啓匡, 安岡 宏, 垣花 眞人, 吉村 昌弘1992 年 39 巻 5 号 p. 366-369
発行日: 1992/05/15
公開日: 2009/05/22
ジャーナル フリーSuperconducting Bi-Pb-Sr-Ca-Cu-O ceramics have been synthesized by the polymerized complex method at the Bi1.8Pb0.2Sr2Ca2 Cu3Oy (A), Bi1.6Pb0.4Sr2Ca2Cu3<Oy (B) and Bi1.68Pb0.32Sr1.75Ca1.82Cu2.83Oy (C) compositions. The present technique offers more convenient and easier fabrication of highly pure and homogeneous (Bi, Pb)-2223 superconductors compared with other elaborate preparation procedures based on wet-chemical techniques. Complex susceptibility measurements show that Tc(onset) of the (Bi, Pb)2223 phase remains almost constant at 108 K independent of the compositions. However, the intergranular coupling between the active (Bi, Pb)-2223 superconducting grains was very dependent on the compositions as well as on the sintering period.抄録全体を表示PDF形式でダウンロード (239K) -
真島 一彦, 長谷川 伸二, 浅田 雅男, 勝山 茂, 永井 宏1992 年 39 巻 5 号 p. 370-373
発行日: 1992/05/15
公開日: 2009/12/04
ジャーナル フリーThe high temperature electrical resistivity and superconducting properties of Bi2Sr2CaCu2Oy heat-treated at 423K in H2 gas were studied. The increment of Tc(on) was recognized on the H-doped samples, but the transition width also increased with the increase of H2 gas pressure. It was recognized that the measurement of Tc for the Bi2Sr2CaCu20y samples under H2 gas pressure above 10.0atm was impossible because of the great increment of electrical resistivity. And it was confirmed that this phenomenon coresponded to the fact that the rapid increase of hydrogen content and unit cell volume were observed at 10.Oatm H2 gas pressure.抄録全体を表示PDF形式でダウンロード (195K) -
草野 圭弘, 山口 一裕, 福原 実, 土井 章, 高田 利夫, 藤原 正志, 高田 潤1992 年 39 巻 5 号 p. 374-377
発行日: 1992/05/15
公開日: 2009/05/22
ジャーナル フリーThe effects of cooling condition and Ba addition time on Tc of high-Tc phase in the Bi-Pb-Sr-Ca-Cu-O system were studied. X-ray diffraction and DC resistance measurements were carried out to observe phase identification and Tc values for a series of samples with compositions of Bi:Pb:Sr:Ba:Ca:Cu=0.9:0.2:1.0:X:1.0:1.6(X=0-0.05). When a mixture of BaCO3 and synthesized high-Tc phase was heated at 850°C for 60h in air, only a solid solution of high-Tc phase was formed in a quenched sample. However, in a sample cooled down slowly, Bi3(Sr, Ba)4Ca3Oz was found as an impurity phase in addition to the solid solution of high-Tc phase. Mixtures of BaCO3 (X=0.04) and the rest of metal oxides or metal carbonates were heated at 845°C 96h in air. Bi3(Sr, Ba)4Ca3Oz was also found in addition to the high-Tc phase in a quenched sample. When BaCO3 was added to the synthesized high-Tc phase, Tc(R=0) was 119K for the heated samples. When BaCO3 was added in starting materials, Tc decreased to 110K due to the formation of Bi3(Sr, Ba)4Ca3OZ.抄録全体を表示PDF形式でダウンロード (194K) -
矢田 節男, 北口 仁, 山本 凉市, 新田 泰弘, 伊藤 秀章, 高田 潤, 池田 靖訓, 高野 幹夫, 中 重治1992 年 39 巻 5 号 p. 378-381
発行日: 1992/05/15
公開日: 2009/12/04
ジャーナル フリーA starting powder for sintering of superconductors in the Bi(Pb)-Sr-Ca-Cu-0 system was prepared by calcining the mixture of a high Tc phase (Bi1.8Pb0.4Sr2.0Ca2.0Cu3.2Oy) and 0.4 mol CaC03 at 800°C for 2h. The sintered compacts were obtained by the two-step sintering. where the starting powder which was press formed at 1-5t/cm2, was primarily sintered at 850t for 20h, then re-press formed at 2-5t/cm2 and finally sintered at 8501; for 120h. The effects of the re-press forming on the densification behavior and superconducting properties were investigated by employing the above two-step sintering. The bulk density of the compact which was primarily sintered after press forming at 3t/cm2 was 4.2g/cm3, while the density increased up to 5.2g/cm3 by secondary sintering after re-press forming at 5t/cm2. A linear relation was found between the Jc values and the bulk densities of the compacts, which were prepared by one-step sintering or two-step sintering at 8500 for 120h. The Jc(77K) value of the compact of theoretical density was estimated by extrapolation to attain a magnitude of 104A/em2.抄録全体を表示PDF形式でダウンロード (1652K) -
大原 泰源, 遠藤 加寿代, 江木 俊雄, 難波 徳郎, 高田 潤, 池田 靖訓, 高野 幹夫, 坂東 尚周, 間崎 啓匡1992 年 39 巻 5 号 p. 382-385
発行日: 1992/05/15
公開日: 2009/12/04
ジャーナル フリーEffects of the Li-addition to the high-Tc phase in the Bi-Pb-Sr-Ca-Cu-O system have been studied for samples with starting compositions of Bi:Pb:Sr:Ca:Cu:Li=0.9:0.2:1.0:1.0:1.6:x with x=0-0.10 and heated at 820-850°C for 40-96h. The temperature, at which an endothermic reaction occurred, lowered markedly as x increased. Tc was raised up to 116K for the sample with x=0.03 heated at 840°C for 48h, while a susceptibility measurement revealed that Tc=110K. The lattice constants, a and c, were independent of Li content. ICP analysis showed that the heat treated samples had very low Li content. The results suggest that a small amount of the high-Tc phase with Tc=116K forms on the surface of the high-Tc phase with Tc=110K.抄録全体を表示PDF形式でダウンロード (249K) -
高田 潤, 藤原 正志, 江木 俊雄, 難波 徳郎, 池田 靖訓, 高野 幹夫, 間崎 啓匡1992 年 39 巻 5 号 p. 386-389
発行日: 1992/05/15
公開日: 2009/12/04
ジャーナル フリーThe effects of Li-addition to the high-Tc phase in Bi-Pb-Sr-Ca-Cu-O system have been studied for the samples with the nominal composition of Bi:Pb:Sr:Ca:(Cu, Li)=0.96:0.24:1.0:1.1:(1.6-x, x) heated at 840 to 845°C for 144h in air (x=0 to 0.2). The characterization of the samples has been made by DTA, the measurements of XRD and DC electrical resistivity, SEM observation and ICP analysis. The Li-addition promotes the formation of the high-Tc phase. The sample with x=0.05 heated at 842°C for 144h exhibits Tc=116K, while Tc=109K for the Li-free sample (x=0) heated at 842°C for 120h. The results of ICP analysis showed that the Li content of the samples heated at 842°C for 120h was very low.抄録全体を表示PDF形式でダウンロード (253K) -
原田 幸明, 本間 一広, 皆川 和己, 奥山 秀男1992 年 39 巻 5 号 p. 390-396
発行日: 1992/05/15
公開日: 2009/05/22
ジャーナル フリーA new method of EPMA mapping was developed and applied to the analysis of Bi-Sr-Ca-Cuoxide phases from atomized glass powder. The EPMA composition-coordinate mapping method, in which the frequency of the located spot-area of the same composition is plotted on thecoordinate with the concentration of each element, clearly showed the phase separationfrom homogeneous glass powder. A localized distribution of composition was found nearCa2CuOx with several percentage of Sr, and the distribution was connected with the mainphase. The main phase also had two spread of distribution to CuO and SrO. In the sampleconventionally mixed and sintered, Cu-rich phase without Bi was appeared instead of CuOand SrO.抄録全体を表示PDF形式でダウンロード (1924K) -
西田 俊彦, 島野 晋, 浦部 和順1992 年 39 巻 5 号 p. 397-400
発行日: 1992/05/15
公開日: 2009/05/22
ジャーナル フリーBi2Sr2CaCu2Ox ceramic powder prepared by a solid state reaction was encupslated in SUS304 stainless steel mold with dimensions of 22φ(O.D.) - 10φ(l.D.) x 25mm. The mold was preheated at 840°C for 10 minutes and was hot-forged under uniaxial compressive load.
Many kinds of disordered nanostructure were observed in the hot-forged ceramics by TEM. They were many dislocation lines, micro-fracture and lattice undulation in crystal grains. The disordered structure changed, however, to a polycrystal composed of small recrystallized grains after annealing at 800°C for 1 hour.抄録全体を表示PDF形式でダウンロード (5496K) -
一ノ瀬 昇, 高橋 慶一, 斉藤 公彦1992 年 39 巻 5 号 p. 401-403
発行日: 1992/05/15
公開日: 2009/05/22
ジャーナル フリーThe Bi-Sr-Ca-Cu-O oxide superconductor has a strong anisotropy in physical and mechanical properties. Therefore, magnetic properties may change with the rate of grain orientation in a polycrystalline sample. In this report, we have studied the relation between ΔM, which is the difference of magnetization of the irreversible M-H curve, and the rate of grain orientation, and their magnetic field dependences of the Bi2Sr2Ca2Cu3Ox ceramics. To have various rates of grain orientation, the hot-forging was performed for the sintered specimens, and X-ray diffraction patterns showed the change of the rate of grain orientation. Measurements of M-H curves were performed using VSM at 77K. The ΔM remarkably changed with the rate of grain orientation at low field, but the change of it became slow with the increase in the magnitude of the magnetic field probably because of the flux creep at the grain boundaries.抄録全体を表示PDF形式でダウンロード (161K) -
江木 俊雄, 森 直元, 細谷 勝宣, 難波 徳郎, 高田 潤1992 年 39 巻 5 号 p. 404-407
発行日: 1992/05/15
公開日: 2009/05/22
ジャーナル フリーThe BPSCCO powder with a nominal composition of Bi:Pb:Sr:Ca:Cu=0.96:0.24:1.0:1.1:1.6 prepared by the co-precipitation method was packed into a Ag tube. The tape was fabricated by plastic deformation. Optimized heat treatment conditions for the tape samples have been studied. The critical current density of the tape samples after the 3rd heat treatment was found to depend on the temperature of the 1st heat treatment. The maximum critical current density was 10, 500A/cm2 at zero field and 77K in the sample subjected to the 1st heat treatment at 845°C. The impurity phases with a particle size of 5-10μm, such as Ca-Sr-Cu-O and Ca-Sr-Pb-O, were present even in the sample with Jc=10, 500A/cm2.抄録全体を表示PDF形式でダウンロード (1961K) -
下嶋 浩正, 塚本 惠三, 石井 守, 山岸 千丈1992 年 39 巻 5 号 p. 408-412
発行日: 1992/05/15
公開日: 2009/05/22
ジャーナル フリーThe relation between the properties of the magnetic detector and the crystalline phase and the microstructure of the superconductor was studied for the Bi system superconductor containing the small amount of Ba.The formation of the high Tc phase was promoted by the addition of Ba. The sensitivity to the magnetic field was improved because of the segregation of the secondary phase at the grain boundaries which worked as weak link.抄録全体を表示PDF形式でダウンロード (1543K)
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