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81.
Wigner function in phase space has its physical meaning as marginal probability distribution in coordinate space and momentum space respectively, here we endow the Wigner function with a new physical meaning, i.e., its marginal distributions’ statistical average for q 2/(2C) and p 2/(2L) are the energy stored in capacity and in inductance of a mesoscopic L-C circuit at finite temperature, respectively. PACS numbers: 03.65.-w, 73.21.-b  相似文献   
82.
For the waveguide grating photocoupler with novel structure [Yu XQ, Zhang X, Wong KS, Xu GB, Xu XG, Ren Y, et al. A fabrication of coupling grating in the polymeric waveguide by using two-photon initiated photopolymerization. Mater Lett 2004;58:3879–83. [1]; Yu XQ, Zhang X, Xu GB, Zhao HP, He W, Shao ZS, et al. Fabrication of grating waveguide and coupling grating using two-photon initiated photopolymerization. Chem J Chin Univ 2004;25(10):1931–3 (in Chinese). [2]], the electric fields of the TE guided wave and the TE radiating wave are obtained by solving the Helmholtz equation in the spatial rectangular coordinates. And then the relations between the loss coefficient and the different structure parameters of the waveguide and grating are analyzed by using the mode coupling theories, and their corresponding numerical simulation results are given. In the end the result obtained for this novel structure and that for conventional rectangle structure are compared, and the difference and the sameness are obtained.  相似文献   
83.
Nanoparticles with different shapes were prepared at the air/water interface via hydrolysis of Pb2+ ions under Langmuir films of poly(N-vinylcarbazole) (PVK) at 30–50 °C. It was found that round or irregular nanoparticles with the size of several to several tens of nanometers were formed when the PbCl2 aqueous solution with the concentration of 1 × 10?3 mol L?1 was used as subphase, while single-crystalline quasi-hexagonal nanoplates, nanostars and dendrites with the size of several hundreds of nanometers were obtained when the subphase concentration was 1 × 10?4 mol L?1. Analysis on the selective-area electron diffraction (SAED) patterns revealed that the formed nanoparticles are β-PbO. The formation of the nanostructures should be attributed to the formation and dehydration of lead hydroxide, diffuse-limited growth and aggregation of nanoparticles at the air/water interface.  相似文献   
84.
FGS was isolated and purified from laminaria japonica by enzymolysis,chromatography methods and so on.The high blood fat model was established by feeding mouse on high fat feedstuff.Compared with control group,the concentration of HDL-C.the ratio of HDL-C.TC increased.while the concentration of TC,LDL-C and TG decreased in experimental groups,Conclusion:FGS was an effective serum lipid regulator and can be developed as medicine and health food.  相似文献   
85.
1. INTRODUCTION Blood fat primarily contains cholesterol, cholesterol ester, phosphatide, triglyceride and free fatty acid in serum of human being and mammalian. Under physiological conditions, the lipids transport in the form of lipoproteins linked with the proteins. Except for the free fatty acid linked with albumin, the other lipids are linked with the globular proteins into high-density lipoproteins (HDL), low density lipoproteins (LDL), very low density lipoproteins (VLDL) and so…  相似文献   
86.
The interaction between 3-(4′-methylphenyl)-5-(4′-methyl-2′-sulfophenylazo) rhodanine (M4MRASP) and bovine serum albumin (BSA) was studied by using spectrofluorimetry. It was shown in fluorescence spectrums that the quenching mechanism of BSA by M4MRASP was a static quenching. Meanwhile, the binding constant and binding site numbers were calculated. The action distance (r = 8.03 nm) and energy transfer efficiency (E = 0.12) between donor (BSA) and acceptor (M4MRASP) were obtained according to the theory of Förster non-radiation energy transfer. The effect of M4MRASP on the conformation of BSA was further analyzed by using synchronous fluorescence spectrometry. A new model of the interaction between small organic molecule and biomacromolecule was established. The results offered a reference for the studies on the biological effects and action mechanism of small molecule with protein.  相似文献   
87.
The catalytic enantioselective arylation of aryl aldehydes using boronic acids as the source of transferable aryl groups is described; the reaction is found to proceed in good yields and in good to high enantioselectivities (up to 99% ee) in the presence of a chiral aminophenol ligand.  相似文献   
88.
In this paper, chemostat model with pulsed input in a polluted environment is considered. By using the Floquet theorem, we find the microorganism eradication periodic solution is globally asymptotically stable if some conditions are needed. At the same time we can find the condition of the nutrient and microorganism are permanent.  相似文献   
89.
Accurate calculation of the almost singular double surface integrals is essential for successful solutions of the magnetic field integral equation (MFIE) by method of moments (MoM) using Rao–Wilton–Glisson (RWG) basis functions, especially for the scattering analysis of small conducting objects. In this paper, an accurate singularity extraction technique to avoid logarithmic singularity of the integration on the testing triangles is used for the MFIE. The numerical examples of several small sharp-edged conducting objects demonstrate that accuracy of the MFIE is improved with the use of the new technique. In addition, the MFIE converges much faster than the electric field integral equation (EFIE) when iterative equation solvers are employed, which means high efficiency and a suitable choice for very low frequency small sharp-edged conducting object problems using this new singularity extraction technique.  相似文献   
90.
The flows that occur in the solution, in the linear approximation, of the problem of the failure of a dam for the model of two-layer shallow water with a free boundary are analysed qualitatively. It is shown that, apart from symmetry, four basic processes and four transients exist. They are distinguished by the type of jumps in the levels on the lines of discontinuity and by the direction of the velocities in the liquid layers. Examples of the profiles of all these flows are presented.  相似文献   
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