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31.
32.
We investigate the overlap of the ground state meson potential with sets of mesonic-trial wave functions corresponding to different gluonic distributions. We probe the transverse structure of the flux tube through the creation of non-uniform smearing profiles for the string of glue connecting two color sources in Wilson loop operator. The non-uniformly UV-regulated flux-tube operators are found to optimize the overlap with the ground state and display interesting features in the ground state overlap.  相似文献   
33.
在一般拓扑学中,有一个著名的杨忠道定理,拓扑空间X的任意子集的导集是闭集的充分必要条件是每个单点集的导集是闭集,本文给出另外两个等价条件,并讨论了T0,T1空间与我们称之为T0.5空间之间的关系。  相似文献   
34.
利用HPLC/DAD-ESI(-)MS联用技术对植物长萼小连翘(Hypericum erectum subsp.longisepalum L.H.Wu et D.P.Yang)中主要化学成分进行了分离分析,初步鉴定出金丝桃素、伪金丝桃素、原伪金丝桃素、绿原酸、芦丁、金丝桃苷、槲皮素等12种黄酮类、酚酸类和金丝桃素类等化学成分.  相似文献   
35.
Glutaconamide-based [2]rotaxanes are efficiently oxidized to the respective interlocked α-ketoamides, whereas their non-interlocked threads afford hydroxycyclohexene tetraamides under similar reaction conditions. These results showcase the mechanically interlocking of highly reactive substrates as a powerful tool for controlling their chemical behavior. Inside the macrocycle and under irradiation with light, the α-ketoamide threads convert, in a divergent manner, into the corresponding interlocked hydroxy-β-lactams or oxazolidinones by two modes of Norrish/Yang type-II intramolecular cyclizations, processes that are efficiently chemocontrolled by the mechanical bond.  相似文献   
36.
Considering a complex Lagrange space ([24]), in this paper the complex electromagnetic tensor fields are defined as the sum between the differential of the complex Liouville 1-form and the symplectic 2-form of the space relative to the adapted frames of the Chern–Lagrange complex nonlinear connection. In particular, an electrodynamics theory on a complex Finsler space is obtained.

We show that our definition of the complex electrodynamics tensors has physical meaning and these tensors generate an adequate field theory which offers the opportunity of coupling with the gravitation. The generalized complex Maxwell equations are written.

A gauge field theory of electrodynamics on the holomorphic tangent bundle is put over T′M and the gauge invariance to phase transformations is studied. An extension of the Dirac Lagrangian on T′M coupled with the electrodynamics Lagrangian is studied and it offers the framework for a unified gauge theory of fields.  相似文献   
37.
欣逢杨振宁先生百年诞辰,已有不少文章总结了杨先生对当代物理学发展的重要科学影响.笔者认为,作为当代最伟大的理论物理学家之一,杨先生不仅以诸多具体的科学贡献推动了当代物理学革命性的进步,而且其独特的科学风格在国际学术界独树一帜,其学术思想更是深邃隽永、对中国和世界的物理学发展有长远的启发作用.笔者将结合学习杨振宁科学思想的体会,联系自己在理论物理研究方面的科学实践(包括在1992—1994年跟随杨先生对量子开系统、超导相变和冷原子物理方面的探索),对当代理论物理发展趋势提出一些个人的看法.文章将通过具体实例,阐述为什么要做"美或有用"的理论物理;为什么基本物理的理论在一段时间内可以与直接的实验验证保持距离?对于后者,本文还从科学方法论(哲学)的角度就理论预言与实验证实的关系进行较为深入的讨论.着眼于"有用"的理论物理-应用理论物理,笔者强调了国家需求驱动的科学研究与自由探索一样,也会导致基础物理的重要突破.  相似文献   
38.
Shengxiang Wang 《代数通讯》2013,41(5):2195-2212
In this paper, we mainly construct the Drinfeld double for braided infinitesimal Hopf algebras in Yetter–Drinfeld categories as a generalization of Aguiar's result.  相似文献   
39.
Yang–Baxter operators from algebra structures appeared for the first time in [11 D?sc?lescu , S. , Nichita , F. ( 1999 ). Yang–Baxter operators arising from (co)algebra structures . Comm. Algebra 27 : 58335845 .[Taylor &; Francis Online], [Web of Science ®] [Google Scholar], 22 Nichita , F. ( 1999 ). Self-inverse Yang–Baxter operators from (co)algebra structures . J. Algebra 218 : 738759 .[Crossref], [Web of Science ®] [Google Scholar], 23 Nuss , P. ( 1997 ). Noncommutative descent and non-abelian cohomology . K-Theory 12 ( 1 ): 2374 .[Crossref] [Google Scholar]]. Later, Yang–Baxter systems from entwining structures were constructed in [8 Brzeziński , T. , Nichita , F. F. ( 2005 ). Yang–Baxter systems and Entwining Structures . Comm. Algebra 33 : 10831093 .[Taylor &; Francis Online], [Web of Science ®] [Google Scholar]]. In fact, Yang–Baxter systems are equivalent with braid systems. In this paper we show that braidings and entwinings of various algebraic structures—in particular, algebra factorisations—can be constructed from a braid system, whence from a Yang–Baxter system as well.  相似文献   
40.
We obtain nontrivial solutions for a class of p-Laplacian problems that are p-superlinear at infinity and nonresonant at zero. The proof is based on showing that the associated variational function has a (generalized) local linking near the origin and makes use of a new sequence of min-max eigenvalues of the p-Laplacian defined using the Yang index.  相似文献   
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