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71.
B. Ya. Balagurov 《Technical Physics》2003,48(8):945-951
A sequential scheme for calculating the polarizability of a pair of parallel cylinders with an arbitrary (but fairly symmetric) form is suggested. An infinite set of algebraic equations is derived for coefficients involved in an expression for the potential. The numerical solution of this set makes it possible to find the polarizability with any degree of accuracy. This method is unrelated to the cylinder shape. The electrostatic properties of the cylinders are described in terms of the multipolar polarizability matrix. 相似文献
72.
V. V. Dvorkin N. N. Dzbanovskii A. F. Pal’ N. V. Suetin A. Yu. Yur’ev P. Ya. Detkov 《Physics of the Solid State》2004,46(4):729-732
A suspension of ultrafine-dispersed nanodiamond was used for introducing (in particular, selectively) high-density centers of diamond nucleation on various substrates. High-quality doped diamond films to be used as electrochemistry electrodes were deposited from the gas phase in a microwave discharge on certain substrates treated using ultrafine-dispersed nanodiamond. A uniform distribution of nucleation centers with concentrations greater than 1010 cm-2 on silicon substrates was obtained. Electrochemical current-potential curves were measured for continuous films. Diamond meshes of different transparency were grown using selective nucleation. Successful production of high-quality doped diamond meshes gives grounds to consider them the most promising electrodes for use in electrochemistry. 相似文献
73.
P. D. Kim I. A. Turpanov S. V. Stolyar R. S. Iskhakov V. I. Yushkov A. Ya. Beten’kova L. A. Li E. V. Bondareva T. N. Isaeva M. M. Karpenko 《Technical Physics》2004,49(4):431-434
The crystal structure and hysteretic magnetic properties of equiatomic single-crystal CoPt films applied on MgO substrates
by magnetron sputtering, as well as modification of these properties by thermal annealing, are studied. Heat-treated films
of thickness in the range 2<d≤16 nm exhibit perpendicular magnetic anisotropy. A correlation between the crystalline anisotropy constant of the CoPt films
and the order parameter of the LI0 superstructure in these alloys is found. The effect of a single-crystalline MgO substrate on the structure and magnetic properties
of equiatomic CoPt films is revealed. 相似文献
74.
75.
M. Ya. Izrailovich 《Acoustical Physics》2004,50(2):163-168
On the basis of the method of equivalent linearization combined with the method of moments, laws of self-oscillation excitation are obtained that provide the modes with maximum intensity of resonance (or quasi-resonance) oscillations in one-dimensional systems with distributed parameters. A restriction of a general type is imposed on the law of excitation. In the particular case of an integral quadratic restriction, the law of excitation leads to the generation of purely harmonic self-oscillations. The use of an extended (multiplicatively stabilizing) control provides the uniqueness and stability of the quasi-optimal mode of self-oscillation. 相似文献
76.
77.
Chunxia Zhao Guowang Xu Xianzhe Shi Jianmei Ma Yan Zhang Shen Lv Qianfeng Weng Qing Yang 《Analytical sciences》2004,20(7):1001-1005
Fluorescent-based single-strand conformation polymorphism (F-SSCP) analysis with capillary electrophoresis (CE) is the most common method for the detection of mutation because of its high sensitivity and resolution. In this study, we prepared an inexpensive linear polyacrylamide (LPA), and successfully applied it to CE-SSCP analysis and tandem CE-SSCP/heteroduplex analysis (HA) of the P53 gene on an ABI capillary genetic analyzer. A comparison of the sieving capabilities of a homemade LPA and commercial polydimethylacrylamide (PDMA) demonstrates that the homemade LPA has a higher resolution, a shorter analysis time, and is more suitable for tandem SSCP/HA than commercial PDMA. To show the usefulness, mutations of P53 gene exon 7 - 8 in 37 tumor samples were investigated by using homemade LPA. The results indicate that 10 mutations were found in 9 of 37 cases; the majority of P53 mutations were missense mutations, and 70% were located in exon 7, which plays an important role in neoplastic progression in human tumorigenesis. 相似文献
78.
介绍了一台10mm口径两级双程离轴放大系统,实现了对5mm×5mm口径光束的激光放大,耦合系统采用高功率LDA紧密侧面直接抽运棒状Nd:YLF方式。分析并实验研究了在不同抽运电流、放大脉冲与放大器LDA抽运时刻的不同延时及不同注入能量条件下,放大系统及光束每次放大时放大特性的规律。实验得到:在放大系统5mm×5mm软光阑处注入1.58mJ能量时,放大系统可输出129.2mJ能量,能量提取效率达到19.5%,满足该系统的设计指标。 相似文献
79.
80.