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991.
Hiroshi Kishi Youichi Mizuno Tomoya Hagiwara Hirokazu Orimo Hitoshi Ohsato 《Journal of Electroceramics》2008,21(1-4):22-28
The effect of re-oxidation treatment on the solubility of dopants and the dielectric properties of rare-earths (La, Ho) and V-substituted BaTiO3 solid solutions, assuming the shell phase of X7R dielectrics, was investigated. Ho-V-substituted samples showed larger increase of the lattice parameter and T c by re-oxidation treatment compared with La-V-substituted samples. Electron spin resonance measurements revealed that the oxidation of V3+ to V4+ or V5+ appeared in the range in which the increase of lattice parameter by re-oxidation treatment was observed. This suggests that the increase of T c is due to the change of preferential occupational site of Ho ion from A-site to B-site, being accompanied with the oxidation of V3+. We also investigated the effect of re-oxidation treatment on the electrical properties and microstructure in Ni-MLCC samples, using rare-earths (La, Ho, Yb) and acceptors (Mn, V) doped BaTiO3 based X7R dielectrics. The change in temperature characteristic of the dielectric constant by re-oxidation treatment was observed for the MLCC samples containing V with smaller content. In the case of Ho-V- and Yb-V-doped samples showed larger increase of the dielectric constant at around 120 °C compared with La-V-doped samples. The relationship between the microstructure and electrical properties of the MLCC sample was investigated by impedance measurement at elevated temperature. 相似文献
992.
Dr. Fumika Karaki Sho Umemoto Karin Ashizawa Tomoya Oki Noriko Sato Takumi Ogino Naoto Ishibashi Ryoto Someya Dr. Kanako Miyano Dr. Shigeto Hirayama Prof. Yasuhito Uezono Prof. Hideaki Fujii 《ChemMedChem》2019,14(21):1840-1848
Although the advantages of sp3-rich, sterically complicated molecules in drug development have been pointed out, modern screening libraries are filled with planar, sp2-rich components. Compounds that are sp3-rich are difficult to synthesize, and thus we aimed to invent an efficient method to construct sp3-rich libraries. By modifying sp3-rich 7-azanorbornane scaffolds through click chemistry, we efficiently prepared a small set of compounds. These compounds were not only sp3-rich, but also had sufficient “lead-like” properties in view of molecular weights and hydrophobicity. Screening assays of this library provided weak κ opioid receptor agonists and growth hormone secretagogue receptor agonists with high hit rates. These results indicate that the 7-azanorbornane scaffold may be a “privileged structure” for lead identification in drug discovery. 相似文献
993.
A new tool has been developed to evaluate the reliability of assembly shop operation. It is a subsystem of AREM (Assembly Reliability Evaluation Method) [1] that can evaluate assembly fault occurrence rates by using product design information. This new tool uses approximately forty questions to assess quantitatively the influence of assembly shop operation reliability on assembly fault occurrence. This method is being used both to improve shop operation reliability and to select preferable shop, and is proven to be effective. The entire AREM system supports efficiently systematic improvement in assembly quality by examining both product design and assembly shop. 相似文献
994.
Hyun-Goo Kim Wha-Nam Myung K. Sumiyama K. Suzuki 《Journal of Alloys and Compounds》2003,360(1-2):168-172
The formation and chemical leaching effects of a nonequilibrium Al0.6(Fe25Cu75)0.4 powder produced by rod milling is described. X-ray diffraction, transmission electron microscopy, differential scanning calorimetry and vibrating sample magnetometry were used to characterize both the as-milled and leached specimens. After 400 h of milling, only the bcc AlFe phase with an amorphous phase was detected in the XRD patterns. The crystallite size for the bcc AlFe phase (110) after 400 h of milling was about 5.3 nm. The peak temperature and the crystallization temperature of the as-milled powders were 448.7 and 428.0 °C, respectively. Al atoms leaching from the as-milled bcc AlFe powders in the L1 condition did not alter the diffraction pattern significantly, even though Al atoms had been removed. After the L1 specimen was annealed at 500 °C for 1 h, the bcc AlFe phase transformed to the fcc Cu, Fe, and CuFe2O4 phases. The peak widths of L1 and L2 specimens were similar, but became broader than that of the as-milled powder. The saturation magnetization decreased with increasing milling time, and a value of 10.4 emu/g was reached after 400 h of milling. After cooling the specimen from 750 °C, the magnetization slowly increased at approximately 491.4 °C, indicating that the bcc AlFe phase had transformed to the fcc Cu and Fe phases. 相似文献
995.
Carlos Angelo Nunes Belmira Benedita de Lima Gilberto Carvalho Coelho Peter Rogl Paulo Atsushi Suzuki 《Journal of Alloys and Compounds》2004,370(1-2):164-168
The currently assessed V–B phase diagram indicates a peritectoid formation at 1727 °C (V3B4+VBV5B6) for the V5B6 boride. The observation of this phase in several as-cast V–B alloys has lead us to a systematic evaluation of its stability, specially its possible formation from the liquid. In this work, V–B alloys (52–56 at.% B range) were produced through arc melting and heat-treated under high vacuum at 2000 °C for 2 h. The materials in both as-cast and heat-treated conditions were characterized through scanning electron microscopy (SEM) (backscattered electron (BSE) images) and X-ray diffraction (XRD). The features observed in the as-cast samples allowed us to conclude that this phase should be formed from the liquid through the L+V3B4V5B6 peritectic reaction. In spite of not reaching equilibrium condition during heat-treating, the results from the characterization of heat-treated samples have indicated the stability of the V5B6-phase at 2000 °C, in disagreement with the currently accepted V–B phase diagram. 相似文献
996.
Kiriyama R Takenaka T Kurisu Y Nozaki D Sato F Kato Y Iida T 《The Review of scientific instruments》2012,83(2):02A324
We measure the ion beam current and the plasma parameters by using the pulse mode microwave operation in the first stage of a tandem type ECRIS. The time averaged extracted ion beam current in the pulse mode operation is larger than that of the cw mode operation with the same averaged microwave power. The electron density n(e) in the pulse mode is higher and the electron temperature T(e) is lower than those of the cw mode operation. These plasma parameters are considered to cause in the increase of the ion beam current and are suitable to produce molecular or cluster ions. 相似文献
997.
Masami Kojima Yukihisa Suzuki Kensuke Sasaki Masao Taki Kanako Wake Soichi Watanabe Maya Mizuno Takafumi Tasaki Hiroshi Sasaki 《Journal of Infrared, Millimeter and Terahertz Waves》2018,39(9):912-925
The objective of this study was to develop a model of ocular damage induced by 40, 75, and 95 GHz continuous millimeter waves (MMW), thereby allowing assessment of the clinical course of ocular damage resulting from exposure to thermal damage-inducing MMW. This study also examined the dependence of ocular damage on incident power density. Pigmented rabbit eyes were exposed to 40, 75, and 95 GHz MMW from a spot-focus-type lens antenna. Slight ocular damage was observed 10 min after MMW exposure, including reduced cornea thickness and reduced transparency. Diffuse fluorescein staining around the pupillary area indicated corneal epithelial injury. Slit-lamp examination 1 day after MMW exposure revealed a round area of opacity, accompanied by fluorescence staining, in the central pupillary zone. Corneal edema, indicative of corneal stromal damage, peaked 1 day after MMW exposure, with thickness gradually subsiding to normal. Three days after exposure, ocular conditions had almost normalized, though corneal thickness was slightly greater than that before exposure. The 50% probability of ocular damage (DD50) was in the order 40?>?95?≈?75 GHz at the same incident power densities. 相似文献
998.
Saito Ken Inoue Chikara Ikegawa Jin Yamazaki Kazuhiko Goto Sota Takamura Masato Mihara Shunsuke Suzuki Shinsuke 《Metallurgical and Materials Transactions A》2020,51(9):4499-4510
Metallurgical and Materials Transactions A - In this study, we investigated the effects of the size and distribution of spheroidized cementite on the characteristics of a punched surface as well as... 相似文献
999.
Natsui Shungo Sudo Takuya Shibuya Ryota Nogami Hiroshi Kikuchi Tatsuya Suzuki Ryosuke O. 《Metallurgical and Materials Transactions B》2020,51(1):11-15
Metallurgical and Materials Transactions B - An in situ observation technique of the TiO2 interfacial behavior in molten LiCl-KCl electrolysis was developed. The variation of the thin TiO2... 相似文献
1000.
High accuracy, wide range, rotation angle measurement by the use of two parallel interference patterns 总被引:4,自引:0,他引:4
Based on the idea of measuring small rotation angles with a parallel interference pattern (PIP), a method is developed to measure large rotation angles accurately. Two parallel PIP's that have different periods are used to measure a rotation angle of an object. The measurement made with a small-period PIP provides a high accuracy, and the measurement made with a large-period PIP provides a wide range. An accurate measurement for wide-range angles is made by combining the two measured values. The accuracy of the phase detection is determined by the periods of two PIP's. Rotation angles from approximately -30 to 30 arc min can be measured with an accuracy of 0.2 arc sec. Analytical results are supported by experimental results. 相似文献