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21.
A macroscopic system which consists of a set of interacting subsystems in an external field is considered. A convenient formula is derived for the mean energy Qj absorbed per unit time by a subsystem. The expression obtained for Qj takes into account that in general the Hamiltonian H of such a system does not coincide with the sum of the Hamiltonians of the subsystems Hj; Qj appears to be the same for various possible definitions of Hj's. 相似文献
22.
Topchieva IN Tonelli AE Panova IG Matuchina EV Kalashnikov FA Gerasimov VI Rusa CC Rusa M Hunt MA 《Langmuir : the ACS journal of surfaces and colloids》2004,20(21):9036-9043
Wide-angle X-ray scattering observations of alpha-cyclodextrin (CD)-poly(ethylene glycol) (PEG) inclusion complexes (ICs) have shown for the first time that two crystalline columnar modifications (forms I and II) are produced in the process of their formation. This was made possible by precise azimuthal X-ray diffraction scanning of oriented IC samples. Form I is characterized by CDs threaded onto PEG chains and arranged along channels in the order head-to-head/tail-to-tail, while form II is formed by unbound CDs also arranged into columns in a head-to-tail and also possibly a head-to-head/tail-to-tail manner, probably as a result of template crystallization on the form I IC crystals. It was shown that similar structural peculiarities are inherent for channel structures based on ICs obtained with PEG with a wide range of molecular weights (MWs). The characteristic feature of ICs based on PEG, especially with MW > 8000, is the presence of unbound polymer in the composition of the complex. The amount of unbound PEG was shown to rise with increasing MW of PEG, resulting in greater imperfections in the IC crystalline structure. The polyblock structure of ICs based on alpha-CD and PEG was therefore proposed. 相似文献
23.
M. Yu. Doladov V. S. Kazakevich I. G. Kalashnikov V. V. Kupaeva V. A. Shcherbakov 《Journal of Applied Spectroscopy》2001,68(4):708-710
The results of an investigation of the reflection spectrum of the human tympanic membrane in the visible and near IR ranges ( = 400–900 nm) are reported. 相似文献
24.
本文采用取样直流极谱, 常规脉冲极谱, 微分脉冲极谱和交流极谱考察了,2,2,6,6-四甲基-4-羟基哌啶 -1-氧和2,2,6,6-四甲基-4-氧哌啶 -1-氧由基及2,2,6,6-四甲基哌啶 -1-氧自由基在水溶液中的还原反应, 并研究了它们的还原经历电化学过程 。 相似文献
25.
26.
N. G. Basov B. L. Vasin A. A. Galichii A. E. Danilov B. Yu. Ivanov M. P. Kalashnikov B. V. Kruglov Yu. A. Mikhailov V. P. Osetrov V. N. Puzyrev A. V. Rode S. M. Savchenko G. V. Sklizkov V. M. Solodkov S. I. Fedotov V. A. Tsitovich L. I. Shishkina 《Journal of Russian Laser Research》1983,4(3):205-220
The construction principle and the applicable system are considered for the highpower laser amplifier module of the “Del'fin” facility, intended for spherical heating of thermonuclear targets. Results are presented of investigations of the radiation parameters of the amplifier module under various operating regimes. The system for focusing the laser radiation on the target surfaces is described and the results of experiments on plasma heating by radiation of three composite laser beams, at a laser energy level up to 1 kJ at a flux density up to 1014 W/cm2, are analyzed. 相似文献
27.
U. B. Imashev S. M. Kalashnikov G. N. Gordeeva 《Chemistry of Heterocyclic Compounds》1983,19(4):369-373
The Lewis acid-catalyzed addition of cyclic orthoformates to vinyl ethyl ether, which leads to the formation of malonaldehyde acetals, was studied. It is shown that of the linear-cyclic malonaldehyde acetals, 2-(2,2-diethoxyethyl)- and 5,5-dimethyl-2-(2,2-diethoxyethyl)-1,3-dioxanes are stable. The transacetalization of 1,1,3,3-tetraethoxypropane with 1,2- and 1,3-diols, which leads to the formation of cyclic malonaldehyde acetals, was studied. The physicochemical constants of the acetals were determined, and their 1H and 13C NMR spectra are described.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 459–463, April, 1983. 相似文献
28.
合成了分别以5-(4-甲基丙烯酰氧苯基)-10,15,20-三苯基锌卟啉(ZnMOTPP)和5-(4-甲基丙烯酰氧苯基)-10,15,20-三苯基钆卟啉(GdMOTPP)为功能单体, 甲基丙烯酸(MAA)为辅助功能单体的甲基磷酸二甲酯(DMMP)分子印迹聚合物微球. 扫描电子显微镜(SEM)表征结果表明, 微球平均粒径为50~100 μm, 粒度均匀. 与甲基丙烯酸作为功能单体的分子印迹聚合物微球的吸附性能和特异性进行对比发现, ZnMOTPP分子印迹微球的吸附性能优于 GdMOTPP分子印迹微球, 金属卟啉分子印迹微球的吸附性能优于仅以甲基丙烯酸作为功能单体的分子印迹微球, 并且微球对其印迹分子DMMP具有特异性吸附. Scatchard分析表明, DMMP分子印迹空穴中只存在一类结合位点, MIPMs-Zn+MAA的最大吸附量Qmax=148 μmol/g, MIPMs-Gd+MAA的Qmax=78.9 μmol/g, MIPMs-MAA的Qmax=13.57 μmol/g. 相似文献
29.
30.
V.L. Kalashnikov 《Applied physics. B, Lasers and optics》2008,92(1):19-23
The effect of the high-order dispersions on a femtosecond pulse enhancement in an external resonator is analyzed. It is shown
that the degradation of the enhancement factor can be partially compensated by adjustment of group-delay, dispersion and incident
pulse width. Presence of a Kerr-medium inside an external resonator results in the stable quasi-soliton formation that improves
the enhancement factor. This provides the enhancement factor growth as well as its robustness against the high-order dispersions,
when the fourth-order dispersion is negative.
PACS 42.65.Re; 42.65.Tg; 42.60.Da; 42.60.Lh 相似文献