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With different amounts of KCl added in the PNBA(p- nitro benzoic acid) aqueous solution, the factors affecting the SERS (Surface Enhanced Raman Scattering) are studied systematically on the surface of Copper. The results show that in PNBA aqueous solution the occurrence of SERS effect stongly depends on the existence of Cl-. The amount of KCl added affects not only the emergence and the intensity of SERS effect, but also the adsorption properties such as the adsorption manner,etc. 相似文献
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超声波波型转换与表面波的检测 总被引:1,自引:0,他引:1
分析了超声波纵波、横波、表面波3种波型的产生条件和声速关系,检测了超声波在固体表面的波型转换,并测量了声表面波的速度,讨论了声表面波在超声延迟线方面的应用. 相似文献
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Many real-world networks such as the protein–protein interaction networks and metabolic networks often display nontrivial correlations between degrees of vertices connected by edges. Here, we analyse the statistical methods used usually to describe the degree correlation in the networks, and analytically give linear relation in the degree correlation. It provides a simple and interesting perspective on the analysis of the degree correlation in networks, which is usefully complementary to the existing methods for degree correlation in networks. Especially, the slope in the linear relation corresponds exactly to the degree correlation coefficient in networks, meaning that it can not only characterize the level of degree correlation in networks, but also reflects the speed that the average nearest neighbours’ degree varies with the vertex degree. Finally, we applied our results to several real-world networks, validating the conclusions of the linear analysis of degree correlation. We hope that the work in this paper can be helpful for further understanding the degree correlation in complex networks. 相似文献
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We propose two irreversible aggregation growth models of aggregates of two distinct species (A and B) to study the interactions between virus aggregates and medicine efficacy aggregates in the virus-medicine cooperative evolution system. The A-species aggregates evolve driven by self monomer birth andB-species aggregate-catalyzed monomer death in model I and by self birth, catalyzed death, and self monomer exchange reactions in model II, while the catalyst B-species aggregates are assumed to be injected into the system sustainedly or at a periodic time-dependent rate. The kinetic behaviors of the A-species aggregates are investigated by the rate equation approach based on the mean-field theory with the self birth rate kernel IA(K)=Ik, catalyzed death rate kernel JAB(k)=Jk and self exchange rate kernel KA(k,l)=Kkl. The kinetic behaviors of the A-species aggregates are mainly dominated by the competition between the two effects of the self birth (with the effective rate I) and the catalyzed death (with the effective rate JB0), while the effects of the self exchanges of the A-species aggregates which appear in an effectiverate KA0 play important roles in the cases of I>JB0 and I=JB0. The evolution behaviors of the total mass MA(t)1 and the total aggregate number MA(t)0 are obtained, and the aggregate size distribution ak(t) of species A is found toapproach a generalized scaling form in the case of I ≧ JB0 and a special modified scaling form in the case of I0. The periodical evolution of the B-monomers concentration plays an exponential form of the periodic modulation. 相似文献
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