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41.
Koji Tsukuma Kuniyoshi Ueda Masahiko Shimada 《Journal of the American Ceramic Society》1985,68(1):4-C-5
Composites of Al2 O3 and Y2 O3 partially-stabilized ZrO2 were isostatically hot-pressed using submicrometer powders as the starting material. The addition of Al2 O3 resulted in a large increase in bending strength. The average bending strength for a composite containing 20 wt% Al2 O3 was 2400 MPa, and its fracture toughness was 17 MN·w−3/2 相似文献
42.
Crystals of ethyl p-chloro α-cyano-β-methyl-cis-cinnamate, C13H12NO2Cl, are orthorhombic, space group Pbcn, with eight molecules per unit cell, a = 17.31, b = 8.68 and c = 17.20 Å. The structure was solved by direct methods and refined subsequently by Fourier techniques. The benzene ring makes a dihedral angle of 60.0° with the ethylenic group. This suggests significant steric effects of the β-methyl group and of the carbonyl group on the orientation of the benzene ring. The conformation of the ethylene bond and the carbonyl group around the Cα? C bond is roughly cisoid and the angle of twist is 16.5°. Nearest-neighbour >C = C <groups make contact across a two-fold axis at a center-to-center distance of 4.33 Å. 相似文献
43.
Zeyun Yu Jun Wang Zhanheng Gao Ming Xu Masahiko Hoshijima 《Computer methods and programs in biomedicine》2014
In this paper we present a new software toolkit for generating and optimizing surface and volumetric meshes from three-dimensional (3D) biomedical imaging data, targeted at image-based finite element analysis of some biomedical activities in a single material domain. Our toolkit includes a series of geometric processing algorithms including surface re-meshing and quality-guaranteed tetrahedral mesh generation and optimization. All methods described have been encapsulated into a user-friendly graphical interface for easy manipulation and informative visualization of biomedical images and mesh models. Numerous examples are presented to demonstrate the effectiveness and efficiency of the described methods and toolkit. 相似文献
44.
A TiN precursor solution was synthesized by galvanostatic electrolysis of Ti metal and isopropylamine at a current density of 50 mA·cm−2 at room temperature. TiN films were prepared by dip-coating of the precursor solution on a Si wafer, followed by two-stage heat treatment at 400°C and a fixed temperature of 800–1200°C in flowing N2 , N2 /NH3 , or NH3 gas. The TiN films were characterized by XRD, chemical analysis, XPS, and electrical resistivity measurements. The TiN films were composed of uniform grains 20 to 200 nm in size with thicknesses ranging from 300 to 400 nm at temperatures of 800–1200°C. The effect of the heat treatment atmosphere (N2 and NH3 ) on the impurity content, crystallinity, particle size, and electrical resistivity is discussed. 相似文献
45.
The H2 evolution reaction from an aqueous Na2SO3 solution proceeded with 3.7% quantum yield under visible light irradiation (λ > 420 nm) on a Zn0.957Cu0.043S solid solution photocatalyst without co‐catalysts such as Pt.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
46.
Kazuo Yamaura Masayoshi Suzuki Minako Yamamoto Rumi Shimada Tetsuya Tanigami 《应用聚合物科学杂志》1995,58(10):1787-1791
The light transmittance of the gels of poly(vinyl alcohol) (PVA)/phenol/water solutions was examined for the entire range of phenol/water content. Excellent transparency was found for the gels with phenol contents of 70–95 vol %. In full consideration of the results for the transparency and melting temperature of the gels and the viscosity and gelation ability of solutions, the PVA solutions of 75 vol % phenol content were selected for the gel spinning. The maximum dynamic moduli of drawn filaments at 25°C (room temperature) were 42 GPa (15x) for atactic PVA and 45 GPa (14x) for syndiotacticity-rich PVA. © 1995 John Wiley & Sons, Inc. 相似文献
47.
Summary Cationic polymerization of CH2=CH-O-CH2CH2C(COOC2H5)3, a vinyl ether with three pendent esters, initiated by the HI/I2 system in toluene at –40 °C afforded living polymers with a controlled molecular weight (
= 103–104) and a narrow molecular weight distribution (
= 1.1–1.2). The number-average molecular weight of the polymers was directly proportional to monomer conversion and the monomer-to-initiator (HI) feed ratio. The polymers obtained with BF3O(C2H5)2 had a fairly high molecular weight (
105,
5 × 104) and a broad molecular weight distribution. The triester vinyl ether was similar in reactivity to alkyl counterparts and one order of magnitude more reactive than the corresponding mono- and diester vinyl ethers. 相似文献
48.
Naoto Kimbara Akio Nishijima Toshio Sato Yuji Yoshimura Hiromichi Shimada Nobuyuki Matsubayashi Akinori Yukimura 《Catalysis Letters》1990,6(3-6):409-415
TiN supported molybdenum sulfide catalysts showed much higher activity for cleavage of C-C bonds than oxide supported molybdenum sulfide catalysts, indicating the possibility of a new generation of supports for hydroprocessing catalysts. 相似文献
49.
M. Shimada M. Koizumi A. Tanaka T. Yamada 《Journal of the American Ceramic Society》1982,65(4):c48-c48
Temperature dependence of KIC values for Si3 N4 bodies sintered at high pressures without additives was studied from room temperature to 1400°C. Little change in KK was found in this range. 相似文献
50.
Toshio Kimura Yoshikatu Okada Takashi Yamaguchi Yuzo Shimada Kazuaki Utsumi 《The Journal of Adhesion》1994,47(1):179-190
Bondability and interfacial reaction between dielectric and insulator layers have been examined to obtain a basic understanding of bonding mechanisms. Lead-containing complex perovskite was used as a dielectric material. Two kinds of glass-ceramics were used as insulator material; lead borosilicate glass containing Al2O3 (insulator A) and the same containing Al2O3 and MgO (insulator B). Dielectric and insulator layers did not bond when insulator A was used. When insulator B was used, however, strong bonding was achieved between the two layers by firing the powder compacts at temperatures between 800° and 1000°C. Addition of MgO to lead borosilicate glass increased the thermal expansion coefficient to that of the dielectric and enhanced the formation of reaction layers, resulting in good bonding. Two reaction layers were identified. The main reaction products were enstatite and bredigite for one layer contacting the dielectric, and enstatite and a compound with the same diffraction pattern as that of faujasite for the other layers contacting insulator B. 相似文献