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171.
172.
Junsaku Nitta Yiping Lin Takaaki Koga Tatsushi Akazaki 《Physica E: Low-dimensional Systems and Nanostructures》2004,20(3-4):429
We report on electron g-factor in an InAs-inserted In0.53Ga0.47As/In0.52Al0.48As heterostructure. The gate voltage dependence of g-factor is obtained from the coincidence method. The obtained g-factor values are surprisingly smaller than the g-factor value of bulk InAs, and it is close to the bare g-factor value of In0.53Ga0.47As. The large change in g-factor is observed by applying the gate voltage. The obtained gate voltage dependence is not simply explained by the energy dependence of g-factor. 相似文献
173.
By using microlocal analysis, the propagation of weak singularities in Cauchy problems for quasilinear thermoelastic systems in three space variables are investigated. First, paradifferential operators are employed to decouple the quasilinear thermoelastic systems. Second, by investigating the decoupled hyperbolic-parabolic systems and using the classical bootstrap argument, the property of finite propagation speeds of singularities in Cauchy problems for the quasilinear thermoelastic systems is obtained. Finally, it is shown that the microlocal weak singularities for Cauchy problems of the thermoelastic systems are propagated along the null bicharacteristics of the hyperbolic operators. 相似文献
174.
Jing Lin CHEN Gang Qiang YIN Zhong Ning CHEN* State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Fuzhou 《中国化学快报》2003,(5)
Great attention is currently paid to the synthesis of polynuclear transition metal complexes as well as their photochemical, photophysical, and electrochemical properties. The design of multicomponent systems capable of performing useful light- and/or redox-induced function is of special interest1. The oxo-centered carboxylate-bridge trinuclear ruthenium clusters have been investigated extensively during recent decades because they have remarkable electron-transfer properties, intense visibl… 相似文献
175.
Chun-Ling Song Lin Xie Zun-Quan Xia 《Journal of Applied Mathematics and Computing》2004,15(1-2):323-331
A new topology in terms of order on fuzzy sets, revealing better the relationship between smooth topology and Chang’s fuzzy topology, is presented in the paper. Some basic properties are discussed. 相似文献
176.
177.
Shy-Der Lin 《Journal of Mathematical Analysis and Applications》2004,294(2):399-411
The main object of this paper is to investigate several general families of hypergeometric polynomials and their associated single-, double-, and triple-integral representations. Some known or new consequences of the general results presented here, involving such classical orthogonal polynomials as the Jacobi, Laguerre, Hermite, and Bessel polynomials, and various other relatively less familiar hypergeometric polynomials, are also considered. Each of the integral representations, which are derived in this paper, may be viewed also as a linearization relationship for the product of two different members of the associated family of hypergeometric polynomials. 相似文献
178.
本文介绍概率抽样法在钢球生产过程中的应用,通过此法确定钢球生产中各工序质量监测的最佳抽检方案,以确保产品被接受的概率最大。 相似文献
179.
Jia‐Yuh Sheu Yeh‐Long Chen Cherng‐Chyi Tzeng Shu‐Lin Hsu Kuo‐Chang Fang Tai‐Chi Wang 《Helvetica chimica acta》2003,86(7):2481-2489
Certain 1‐ethyl‐ and 1‐aryl‐6‐fluoro‐1,4‐dihydroquinol‐4‐one derivatives were synthesized and evaluated for antimycobacterial and cytotoxic activities. Preliminary results indicated that, for 1‐aryl‐6‐fluoroquinolones, both 7‐(piperazin‐1‐yl)‐ and 7‐(4‐methylpiperazin‐1‐yl) derivatives, 9b and 11a , are able to completely inhibit the growth of M. tuberculosis at a concentration of 6.25 μg/ml, while the 7‐[4‐(2‐oxo‐2‐phenylethyl)piperazin‐1‐yl] derivative 13 exhibits only 31% growth inhibition at the same concentration. For 1‐ethyl‐6‐fluoroquinolones, both 7‐[4‐(2‐oxopropyl)piperazin‐1‐yl]‐ and 7‐[4‐(2‐oxo‐2‐phenylethyl)piperazin‐1‐yl]‐derivatives, 2a and 2b , respectively, show complete inhibition, while their 2‐iminoethyl and substituted phenyl counterparts 3a and 2c are less active. In addition, the 6,8‐difluoro derivative was a more‐favorable inhibitor than its 6‐fluoro counterpart ( 2b vs. 2d ). These results deserve full attention especially because 2a, 2b, 9b , and 11a are non‐cytotoxic at a concentration of 100 μM . Furthermore, compound 9b proved to be a potent anti‐TB agent with selective index (SI)>40 and an EC90 value of 5.75 μg/ml. 相似文献
180.