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121.
Phase transformations in Au-Cu-Pd single-phase alloys Were studied. Age-hardening of the alloys examined vvas attributed to the formation of fine domainu of long-range ordered (LRO) AuCuI type lattice in the interior of the grain. Prolonged ageing caused formation of large LRO domains of single variant at the grain boundary or microtwinning of LRo in the interior of the grain, depending on the ordering rate of the alloy. The electron-atom ratio (e/a) of the alloy and the axial ratio (c/a) of the ordered lattice seemed to playa part in the phase transformation behaviour in this alloy system. The effectiveness of rhodium addition on the grain refining was proved experimentally. These resuRs will be helpful in developing low nobility and high corrosion resistant dental alloys. 相似文献
122.
Kazuhiro Saito Mitsuru Yoneyama Mitsuyoshi Saito Keiichi Ikegami Michio Sugi
Takayoshi Nakamura
Mutsuyoshi Matsumoto Yasujiro Kawabata 《Thin solid films》1988,160(1-2):133-137Photoelectric cells based on Langmuir-Blodgett (LB) films were fabricated using dye monolayers as photoconductors and N-docosylpyridinium-di(tetracyanoquinodimethane) (PT) monolayers as one of the electrode materials. It is found that PT films can be used as a wiring material instead of large work function metals such as silver or Ni-Cr. However, in comparison with the photoelectric cells using the conventional metals, a few different properties were observed for those wired with PT. These differences are assignable to the difference between the LB film-metal and the LB film-LB film contacts. 相似文献
123.
Ryuichi Shimokawa Michio Tajima Masatoshi Warashina Yusaku Kashiwagi Hitoshi Kawanami 《Solar Energy Materials & Solar Cells》1997,48(1-4)
We report the correspondence between the photoluminescence (PL) measurement, monochromatic-light-beam-induced current (MBIC) measurement and defect delineation in polycrystalline cast-Si solar cells. It was found that the peak of the band-edge PL emission in the hydrogenerated and non-hydrogenerated cast-Si shifted from 1.093 eV in the single crystalline CZ-Si to 1.075 eV at room temperature and the band-edge PL mapping corresponded with the MBIC mapping and defect delineation pattern if excluding the surface damages delineated by the MD-1 etchant. 相似文献
124.
Kohji Yoshinaga Takafumi Yokoyama Yutaka Sugawa Hiroyuki Karakawa Naoyuki Enomoto Hiroyasu Nishida Michio Komatsu 《Polymer Bulletin》1992,28(6):663-668
Summary Radical polymerizations of vinyl monomers using a initiator of 2,2-azobis(2-amidinopropane) dihydrochloride on monodispersed silica colloid led to formation of spherical polymer/SiO2 composites, retained particle size. Addition of hydroxypropyl cellulose to the reaction system resulted in yielding excellent dispersible composites into ethanol by short period ultrasonic irradiation. The polymerization of styrene in the presence of mercapto-amine or carboxylic acid derivatives could successfully introduce amino or carboxyl group on the Poly(styrene)/SiO2 composite. 相似文献
125.
Protein Folding in the Presence of Water‐Soluble Cyclic Diselenides with Novel Oxidoreductase and Isomerase Activities
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Dr. Kenta Arai Haruhito Ueno Yuki Asano Gaurango Chakrabarty Shingo Shimodaira Prof. Dr. Govindasamy Mugesh Prof. Dr. Michio Iwaoka 《Chembiochem : a European journal of chemical biology》2018,19(3):207-211
The protein disulfide isomerase (PDI) family, found in the endoplasmic reticulum (ER) of the eukaryotic cell, catalyzes the formation and cleavage of disulfide bonds and thereby helps in protein folding. A decrease in PDI activity under ER stress conditions leads to protein misfolding, which is responsible for the progression of various human diseases, such as Alzheimer's, Parkinson's, diabetes mellitus, and atherosclerosis. Here we report that water‐soluble cyclic diselenides mimic the multifunctional activity of the PDI family by facilitating oxidative folding, disulfide formation/reduction, and repair of the scrambled disulfide bonds in misfolded proteins. 相似文献
126.
127.
In injection molded specimens consisting of isotactic polypropylene (iPP)/poly(ethylene-co-octene) (EOR) blends with different viscosity ratio of η(EOR)/η(iPP), the coefficient of linear thermal expansion (CLTE) was investigated by thermal mechanical analysis (TMA). It was found that the blend with a smaller viscosity ratio showed the larger anisotropy of CLTE depending upon the directions. TEM observations revealed that the shape of rubber domains varied from slabs, cylinders to ellipsoids in shape, by increasing η(EOR)/η(iPP). The crystal orientation analysis by WAXD have revealed that the blend with ‘slab’ EOR domains showed the orientation of the c-axis of iPP crystals was preferably oriented to FD (flow direction) and TD (transverse to FD), and that the b-axis was exclusively oriented to ND (thickness direction). The CLTE of each FD and TD was in good agreement with the rules-of-mixing for CLTE by introducing the effect of the arrays of the elastomer domains and the PP crystal orientation. On the other hand, the CLTE in ND showed massive discrepancy between the calculation and observation. It was found that the incorporation of the retraction effect could explain the discrepancy to some extent. 相似文献
128.
Mototsugu Sakai Hiroyuki Hanyu Michio Inagaki † 《Journal of the American Ceramic Society》1995,78(4):1006-1012
Fracture mechanics are examined for the Vickers-indentation-induced contact deformation and damage of glassy carbons produced by different densification processes. The indentation load versus indentation depth relationship during the loading-unloading cycle reveals that the contact deformation is purely elastic even under such a sharp indentation, which subsequently leads to an indentation-induced ring/cone crack system instead of the median/radial crack system. The processes and mechanisms of such an anomalous surface crack system are related to the very open microstructure of glassy carbons. The ring/cone cracks induced by Vickers indentation are, however, significantly different in nature from the well-known Hertzian cone crack which is induced by pressing a spherical indenter on a brittle surface. Demonstrated is the superiority of glassy carbons to ordinary brittle ceramic materials in resistance to strength degradation by contact with hard particles such as in ballistic situations. 相似文献
129.
Hiromichi Sagitani Yoshie Hayashi Michio Ochiai 《Journal of the American Oil Chemists' Society》1989,66(1):146-152
The synthesis and solution properties of a homologous series of polyglycerol dodecyl ethers (R12Gn) are described. The phase behavior, surface tension, cloud point and HLB value (hydrophile lipophile balance) of these surfactants
in aqueous solutions and in mixed solutions of water/oil have been investigated and compared with values for polyoxyethylene
dodecyl ether (R12EOn). The surface tension measurements showed that R12Gn have sufficiently low values of surface tension and critical micellization concentration (cmc) to serve as useful nonionic
surfactants. The mesophases appearing in the R12Gn systems were more stable in a high temperature range than the mesophases of the R12EOn systems. The cloud point and HLB data indicated that addition of one glycerol group was equivalent to the addition of three
oxyethylene units, as far as the hydrophilic property was concerned. The phase diagrams of the R12Gn/dodecane/water systems showed that the solubilizing and emulsifying powers of R12Gn were greater than those of R12EOn. It is concluded that the polyglycerol chain can be even more useful as the hydrophilic part of nonionic surfactants than
the conventional oxyethylene chain. 相似文献
130.
Masaaki Kitano Ryo Mitsui Diana Rakhmawaty Eddy Zeinhom M. A. El-Bahy Masaya Matsuoka Michio Ueshima Masakazu Anpo 《Catalysis Letters》2007,119(3-4):217-221
Nanowire TiO2 thin films were successfully prepared on Ti metal substrates by hydrothermal treatment of calcined Ti foils in 10 M NaOH.
The nanowire TiO2 thin films exhibited much larger surface area and higher photoelectrochemical performance than the TiO2 thin films prepared on Ti metal substrates by the calcination of Ti foil. These nanowire films were shown to act as an efficient
photoanodes for the photoelectrochemical water splitting reaction. 相似文献