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991.
By making use of the U(1) gauge potential decomposition theory and
the φ-mapping topological current theory, we investigate the
Schrödinger-Chern-Simons model in the thin-film superconductor system and obtain an exact Bogomolny self-dual
equation with a topological term. It is revealed that there exist self-dual vortices in the system. We study the inner topological structure of the self-dual vortices and show that their
topological charges are topologically quantized and labeled by
Hopf indices and Brouwer degrees. Furthermore, the vortices are
found generating or annihilating at the limit points and
encountering, splitting or merging at the bifurcation points of
the vector field φ. 相似文献
992.
993.
以无致癌毒性的1,4-二氯甲氧基丁烷为氯甲基化试剂,先将交联聚苯乙烯(CPS)微球氯甲基化,制得氯甲基化微球CMCPS。 然后使微球CMCPS与4-吡啶甲醛进行季铵化反应,将4-吡啶甲醛键合到CPS微球表面,制得键合吡啶甲醛(PyAL)的改性微球PyAL-CPS。 考察了主要反应条件对季铵化反应的影响,最终确定季铵化反应的优化条件:溶剂CCl4,反应温度60 ℃,最后使改性微球PyAL-CPS、4-吡啶甲醛及吡咯在固-液界面上进行Adler反应,形成固载吡啶基卟啉(PyP)的微球PyP-CPS。 用IR和UV-Vis以及Zn2+配合物生成法表征了微球PyP-CPS的形成及负载量。 相似文献
994.
995.
溅射工艺参数对硅薄膜微结构影响的Raman分析 总被引:2,自引:0,他引:2
为了解决碳化硅难以进行光学加工的问题,该文采用射频磁控溅射方法,在碳化硅反射镜坯体上沉积与碳化硅具有相近热膨胀系数且易于进行光学加工的硅薄膜。利用拉曼光谱(Raman)对衬底温度、射频功率、衬底偏压等溅射工艺条件对硅膜微结构的影响进行了分析。研究发现:随着衬底温度的升高,薄膜的晶化率先增大后减小;衬底偏压的增加不利于薄膜有序结构的形成;射频功率对薄膜微结构的影响比较复杂,随着功率的升高,薄膜晶粒尺寸减小,晶化率降低,当射频功率进一步升高时,薄膜中有序团簇尺寸和晶化率逐渐升高。但过高的射频功率反而不利于薄膜的晶化。 相似文献
996.
Carboxyltransferase domain(CT) of acetyl-coenzyme A carboxylase(ACCase, EC 6.4.1.2) from a family of Poaceae is an important target of commercial herbicide APPs for controlling grass weed growth. As the abuse of APPs herbicides, the resistant ACCase due to the mutation of a single residue(Ile→Leu), which is lo-cated in CT active site, is emergent in many populations and species of Poaceae. So it is urgent to understand the re-sistant mecha-nism so as to design new effect herbicides. Herein lies the complex of CT dimmer from Lolium rigi-dum and herbicide haloxyfop successfully constructed for wild type enzyme and Ile/Leu mutant, respectively, pro-viding a basis for explaining the resistance from microscopic structure. Moreover, the binding free energy difference between wild type and mutant enzymes was predicted in good agreement with the known observation, and the various contributions to it were analyzed, by Molecular mechanics-Poisson-Boltzmann surface area(MM-PBSA) method. The results indicate the van der Waals interaction difference between the protein and inhibitor, –22.94 kJ/mol of CT wild type lower than that of mutant, is the major reason for resistance. Structure analysis further suggests that van der Waals interaction difference is originated from the steric hindrance between the side chain of mutated residue Leu and the chiral methyl group of haloxyfop. All these findings enhance the understanding of resistant mechanism of ACCase to herbicide by Ile/Leu mutation and provide an important clue for the rational design of high effective herbicides. 相似文献
997.
利用场发射扫描电子显微镜(FESEM)和X射线能谱仪(EDS)研究了高温高压触媒法合成金刚石后金刚石/触媒界面的物相组成,发现铁镍元素与碳元素的原子比为3.1: 1,并分析得出高温高压下界面中存在Fe3C、Ni3C物相结构.据此,利用热力学中经典的ΔG<0判定法,计算Me3C(Me:Fe,Ni)物相分解出金刚石的自由能变化.结果表明:在触媒法合成金刚石条件下(1500~1700 K、5~6 GPa),Me3CC(金刚石)+3Me比石墨金刚石的ΔG更负.因此,从热力学角度看,Me3C的形成,尤其是铁基触媒中Fe3C、Ni3C的形成,说明触媒法合成金刚石单晶是来自于Me3C型碳化物的分解,而并非石墨结构的直接转变. 相似文献
998.
In order to clarify the mechanism of optical transitions for cubic SrHfO3, we have investigated the electronic structure and optical properties of cubic SrHfO3 using the plane-wave ultrasoft pseudopotential technique based on the first-principles density-functional theory (DFT). The ground-state properties, obtained by minimizing the total energy, are in favorable agreement with the previous work. From the band structure and charge densities as well as the theory of crystal-field and molecular-orbital bonding, we have systematically studied how the optical transitions are affected by the electronic structure and molecular orbitals. Our calculated complex dielectric function is in good agreement with the experimental data and the optical transitions are in accord with the electronic structure. 相似文献
999.
Under investigation in this paper are two coupled integrable dispersionless (CID) equations modeling the dynamics of the current-fed string within an external magnetic field. Through a set of the dependent variable transformations, the bilinear forms for the CID equations are derived. Based on the Hirota method and symbolic computation, the analytic N-soliton solutions are presented. Infinitely many conservation laws for the CID equations are given through the known spectral problem. Propagationcharacteristics and interaction behaviors of the solitons are analyzed graphically. 相似文献
1000.
本文采用具有较大双光子吸收截面的有机分子2,5,2′,5′-(4′-N,N-二苯胺苯乙烯基)联苯(DPA-TSB)(双光子吸收截面δ: 3288 GM, 1 GM=1×10-50 cm4·s·photon-1·molecule-1), 通过再沉淀法制备水相分散的纳米粒子. 研究表明, 这种有机双光子纳米粒子可以有效地富集在细胞质中, 对细胞染色显示出良好的荧光成像能力. 相似文献