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排序方式: 共有337条查询结果,搜索用时 343 毫秒
31.
Koki Horikoshi 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2004,80(4):166
The term alkaliphile is used for microorganisms that grow optimally or very well at pH values above 9, but cannot grow or grow only slowly at the near neutral pH value of 6.5. Alkaliphiles include prokaryotes, eukaryotes, and archaea. Alkaliphiles can be isolated from normal environments such as garden soil, although viable counts of alkaliphiles are higher in samples from alkaline environments. The cell surface plays a key role in keeping the intracellular pH value in the range between 7 and 8.5, allowing alkaliphiles to thrive in alkaline environments. Alkaliphiles have made a great impact in industrial applications. Biological detergents contain alkaline enzymes, such as alkaline cellulases and/or alkaline proteases that have been produced from alkaliphiles. Another important application is the industrial production of cyclodextrin with alkaline cyclomaltodextrin glucanotransferase. This enzyme reduced the production cost and paved the way for cyclodextrin use in large quantities in foodstuffs, chemicals and pharmaceuticals. It has also been reported that alkali-treated wood pulp could be biologically bleached by xylanases produced by alkaliphiles. 相似文献
32.
Shigeki Habaue Ryo Muraoka Akiko Aikawa Soichiro Murakami Hideyuki Higashimura 《Journal of polymer science. Part A, Polymer chemistry》2005,43(8):1635-1640
The oxidative coupling polymerization of 2,3‐dihydroxynaphthalene with the novel dinuclear‐type copper(II) catalysts successfully produced poly(2,3‐dihydroxy‐1,4‐naphthylene). For example, the MeOH‐insoluble polymer with a number average molecular weight of 4.4 × 103 from the polymerization using the complex of CuCl2 and N,N′‐bis(2‐morpholinoethyl)‐p‐xylylenediamine ( p ‐ 1 ) at room temperature under an O2 atmosphere followed by acetylation of the hydroxyl groups was obtained in 63% yield. The structures of the tetraamine ligands and the counter anion of the copper(II) salts significantly influenced the catalyst activity. The polymerization of 2,2′‐dimethoxy‐1,1′‐binaphthalene‐3,3′‐diol with the 2CuCl2‐ p ‐ 1 catalyst, however, resulted in a lower yield. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1635–1640, 2005 相似文献
33.
Electroluminescent porous Si (PS) diodes exhibit various useful functions under a high-electric field. The experimental PS diodes are composed of thin semitransparent metal films, PS layers (about 500 nm thick in minimum), p- or n-type Si substrates and ohmic back contacts. Definite nonlinear electrical behavior (negative resistance and nonvolatile bistable memory effects) and cold electron emission phenomena appear in these PS diodes associated with the EL emission. Both the negative resistance and memory effects are related to the charging of Si nanocrystallites by field-induced carrier injection. The electron emission observed in the PS diodes formed on n+–Si substrates is caused by hot electrons tunnelling through the top contact. By an appropriate structural control of PS, the effective drift length under a high-field conduction is significantly increased, and then electrons are emitted ballistically. These functions reflect the activity of PS as a nanocrystalline confined system. 相似文献
34.
A novel synthesis of a series of 2,6-disubstituted 3,5-dicyano-4-thiopyridones 4 by the decomposition of 2,4-disubstituted 5-cyano-2-cyanomethyldihydro-1,3-thiazine-6-thiones 2 , which are synthesized from 4-substituted 5-cyano-1,3-thiazine-2,6-dithiones and enaminonitriles, is described. 相似文献
35.
Hiroaki Muraoka Setsuo Yamamoto Yoshihisa Nakamura 《Journal of magnetism and magnetic materials》1993,120(1-3):323-326
The medium noise in perpendicular magnetic recording is discussed. The perpendicular recording mode was expected to prevent zig-zag walls around transitions, and the experimental result of low transition noise in Co-Cr media confirms this. Also, the main origin of the noise is concluded to be irregular clusters of grains in the film. 相似文献
36.
Hidematsu Suzuki Yoichiro Muraoka Hiroshi Inagaki 《Journal of Polymer Science.Polymer Physics》1981,19(2):189-196
Light scattering measurements were carried out on a linear polyethylene sample NBS 1475 in 1-chloronaphthalene at 135 and 115°C to determine the weight-average molecular weight, the second virial coefficient A2, and the z-average mean-square radius of gyration. By use of these results, the system is analyzed in terms of the interpenetration function Ψ for A2. Observed values of A2 are rather large but the excluded volume is nevertheless relatively small. Such behavior seem to be similar to that of semiflexible polymers. The characteristic ratio Cn,LS as determined by light scattering is found to be almost twice the literature value of 6.7, which was obtained from viscosity measurements. This discrepancy is explained by comparing the theoretical value of the Flory viscosity parameter Φ at the nondraining limit with values calculated from the light scattering results. 相似文献
37.
38.
pTa interactions have been studied. The total inelastic cross section, multiplicities, net charge distributions and inclusive momentum and rapidity spectra for produced particles are reported. The correlations between fast and slow particles are presented and the reaction mechanisms for multiparticle production in pTa interactions are discussed. 相似文献
39.
T. Okada S. Inoue T. Ohga K. Muraoka M. Akazaki 《International Journal of Infrared and Millimeter Waves》1985,6(9):883-892
A D2O laser has been developed for collective Thomson scattering measurements of ion temperature in high temperature plasmas. A pulse duration and a spectral width of a high power D2O laser has been successfully controlled for this purpose, by using a TEA CO2 laser injection-locked by an etalon-tuned TEA CO2 laser as a pump source. 相似文献
40.
Wataru Higemoto Kanetada Nagamine Shinji Kuroda Koki Takita 《Molecular Crystals and Liquid Crystals》2013,570(2):51-56
Abstract The microscopic state of the positively charged light particle in the transition metal dichalcogenide 2H-NbSe2 was studied using the muon spin relaxation method (μ+SR) and muon level crossing resonance method (μ-LCR). Muons are expected to stay at interlayer position and behaves as a hydrogen like intercalant. We discuss the relation between conduction electron properties and the muon's behavior. 相似文献