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量子绝热近似条件与量子几何势
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作者 易学华 陈泗凯 +2 位作者 赖鹏华 卜寿亮 钟庆湖 《量子电子学报》 CAS CSCD 北大核心 2014年第2期129-134,共6页
阐述了传统量子绝热定理,给出了传统的量子绝热近似条件.基于传统量子绝热近似条件存在的不足,采用微扰论思想,通过U(1)绝热变换,给出并讨论了新的绝热理论以及新的绝热近似条件.对新的绝热条件中所包含量子几何势的几何性进行了较为深... 阐述了传统量子绝热定理,给出了传统的量子绝热近似条件.基于传统量子绝热近似条件存在的不足,采用微扰论思想,通过U(1)绝热变换,给出并讨论了新的绝热理论以及新的绝热近似条件.对新的绝热条件中所包含量子几何势的几何性进行了较为深入的分析和讨论. 展开更多
关键词 量子物理 量子绝热定理 绝热近似条件 绝热U(1)不变基 量子几何势
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书法势理论在结字中的应用研究--以《张迁碑》为例
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作者 亓汉友 《艺术科技》 2023年第7期103-105,共3页
书法势是指怎样构建某种书势,内容包括利用的书法因素、构建方法、书势的形态等,所以被称为书法势,如果用这种思路来构建字的结构那就是字法势。文章基于书势和书法势内涵的不同,提出构建字法势的过程,即字法布势、字法攻势、书法守势,... 书法势是指怎样构建某种书势,内容包括利用的书法因素、构建方法、书势的形态等,所以被称为书法势,如果用这种思路来构建字的结构那就是字法势。文章基于书势和书法势内涵的不同,提出构建字法势的过程,即字法布势、字法攻势、书法守势,并总结两种字法势分析方法,即松紧字法势因素分析方法和几何线条字法势因素分析方法。首先,在松紧字法势因素分析法中,总结出了紧势因素和松势因素,提出了字法势的布势法则,总结了松紧字法势的几种常见的形式,并选取隶书《张迁碑》中的例字进行松紧势字法势因素分析。其次,在几何线条字法势因素分析中,总结了常见的几何线条字法势因素,分析了不同几何线条字法势可能包含的意义,进一步总结了几何线条字法势因素分析法的概念,并对隶书《张迁碑》中的例字进行几何线条字法势因素分析。最后,指出利用松紧字法势因素和几何线条字法势因素构建的字法势的不同特点,以及两种不同字法势因素在字法势中的不同作用,为当代书法创作特别是字法势的创作提供了新的思路。 展开更多
关键词 书法 字法 松紧因素 几何线条因素
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薄壁量子化方法进展
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作者 王永龙 杜龙 《物理学进展》 北大核心 2024年第1期9-18,共10页
微纳加工技术的快速发展实现了具有非平庸几何结构的低维材料与结构的制备,使得受几何性质影响的有效动力学问题受到关注。作为研究低维弯曲系统中量子力学的有效方法,薄壁量子化方法,它给出的几何势和几何动量也得到实验的证实。本文... 微纳加工技术的快速发展实现了具有非平庸几何结构的低维材料与结构的制备,使得受几何性质影响的有效动力学问题受到关注。作为研究低维弯曲系统中量子力学的有效方法,薄壁量子化方法,它给出的几何势和几何动量也得到实验的证实。本文将回顾薄壁量子化方法,简述其基本计算框架,明确给出几何量子效应是来自于微分同胚变换和局域标架间的旋转变换。这对于理解引力规范场,演生规范场很有帮助,对理解人工规范场所隐含的几何结构也很有帮助。在特定的量子体系中,几何量子效应可表现为共振隧穿、量子阻塞、量子霍尔效应、量子霍尔黏性、量子自旋霍尔效应和单极磁场等,这些结果从不同角度展示了几何与新奇的物理现象之间的联系。 展开更多
关键词 几何势 几何动量 几何规范 薄壁量子化方法 量子霍尔效应
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Geometrical Structures and Electronic Properties of Copper-Doped Aluminum Clusters 被引量:2
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作者 Xi-hui Cheng Da-jun Ding +1 位作者 Yong-gang Yu Ming-xing Jin 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2012年第2期169-176,I0003,共9页
Using density function theory (DFT), the Cu-doped Aln (n=1-15) clusters have been stud- ied. The electron affinity, ionization potential, Mulliken population analysis of Cu, mean polarizability, polarizability ani... Using density function theory (DFT), the Cu-doped Aln (n=1-15) clusters have been stud- ied. The electron affinity, ionization potential, Mulliken population analysis of Cu, mean polarizability, polarizability anisotropy, dipole moments and HOMO-LUMO gaps have also been calculated on the basis of optimized geometries. The results indicate that there is magic numbers in copper-doped aluminum clusters and electronic characteristic depended on the size of clusters. As n=13, the electron affinity and ionization potential of cluster changed more than 0.3 and 0.6 eV respectively, compared with neighborhood clusters. 展开更多
关键词 Density function theory electronic properties Cu doped A1 clusters
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A study of the logical model of capital market complexity theories
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作者 张大勇 吴冲 +1 位作者 周建 田秋生 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2006年第1期37-42,共6页
Analyzes the shortcomings of the classic capital market theories based on EMH and discloses the complexity essence of the capital market. Considering the capital market a complicated, interactive and adaptable dynamic... Analyzes the shortcomings of the classic capital market theories based on EMH and discloses the complexity essence of the capital market. Considering the capital market a complicated, interactive and adaptable dynamic system, with complexity science as the method for researching the operation law of the capital market, this paper constructs a nonlinear logical model to analyze the applied realm, focal point and interrelationship of such theories as dissipative structure theory, chaos theory, fractal theory, synergetics theory, catastrophe theory and scale theory, and summarizes and discusses the achievements and problems of each theory. Based on the research, the paper foretells the developing direction of eomplexity science in a capital market. 展开更多
关键词 capital market logical model COMPLEXITY FRACTAL CHAOS scale theory
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钇小团簇的结构和电离势的计算 被引量:10
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作者 毛华平 杨兰蓉 +2 位作者 王红艳 朱正和 唐永建 《物理学报》 SCIE EI CAS CSCD 北大核心 2005年第11期5126-5129,共4页
采用密度泛函DFT中的B3LYP方法,选择LANL2DZ双ζ基组,优化并得到了Yn=(n=2—8)小团簇的基态平衡结构,同时计算出其电离势.结果表明,钇原子之间形成团簇最稳定的结构是倾向于平均配位数最大,其电离势没有“奇-偶”振荡或“幻数”效应,表... 采用密度泛函DFT中的B3LYP方法,选择LANL2DZ双ζ基组,优化并得到了Yn=(n=2—8)小团簇的基态平衡结构,同时计算出其电离势.结果表明,钇原子之间形成团簇最稳定的结构是倾向于平均配位数最大,其电离势没有“奇-偶”振荡或“幻数”效应,表明Yn团簇光致电离开始主要发生在Y原子局域化的4d轨道上的电子而不是在5s上.对Tomasz提出的钇团簇电离势的解析式进行合理地修正,修正后电离势解析式的计算值与实验值更接近. 展开更多
关键词 Y团簇 密度泛函 平衡几何结构 电离 平衡结构 电离 计算值 团簇 B3LYP方法 平均配位数 密度泛函 光致电离
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SOBOLEV INEQUALITY ON RIEMANNIAN MANIFOLDS
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作者 WANG MENG Department of Mathematics, Zhejiang University, Hangzhou 310027, China School of Mathematical Sciences, Pudan University, Shanghai 200433, China. 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2005年第4期651-658,共8页
Let M be an n dimensional complete Riemannian manifold satisfying the doublingvolume property and an on-diagonal heat kernel estimate. The necessary-sufficientcondition for the Sobolev inequality ‖f‖q ≤ Cn,,v,p,q(... Let M be an n dimensional complete Riemannian manifold satisfying the doublingvolume property and an on-diagonal heat kernel estimate. The necessary-sufficientcondition for the Sobolev inequality ‖f‖q ≤ Cn,,v,p,q(‖▽f‖p+‖fp) (2≤p<q<∞) is given. 展开更多
关键词 Sobolev inequality Complete manifold Riesz transform POTENTIAL Heat kernel
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Theoretical Study on the Low-Lying Electronic States of He_2,He_2^+,and He_2^(++)
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作者 张云光 查新未 高涛 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第6期1048-1052,共5页
The equilibrium geometries, potential energy curves, spectroscopic dissociation energies of the ground and low-lying electronic states of He2, He2^+ and He2^++ are calculated using symmetry adapted cluster/symmetry... The equilibrium geometries, potential energy curves, spectroscopic dissociation energies of the ground and low-lying electronic states of He2, He2^+ and He2^++ are calculated using symmetry adapted cluster/symmetry adapted cluster-configuration interaction (SAC/SAC-CI) method with the basis sets CC-PV5Z. The corresponding dissociation limits for all states are derived based on atomic and molecular reaction statics. The analytical potential energy functions of these states are fitted with Murrell-Sorbie potential energy function from our calculation results. The spectroscopic constants Be, αe, ωe, and ωeχe of these states are calculated through the relationship between spectroscopic data and analytical energy function, which are in well agreement with the experimental data. In addition, the origin of the energy barrier in the ground state X^I∑9^+ of He2^++ energy curve are explained using the avoided crossing rules of valence bond model. 展开更多
关键词 potential energy curve spectroscopic data Murrell-Sorbie function
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Ergodicity and First Passage Probability of Regime-Switching Geometric Brownian Motions
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作者 Jinghai SHAO 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2018年第4期739-754,共16页
A regime-switching geometric Brownian motion is used to model a geometric Brownian motion with its coefficients changing randomly according to a Markov chain.In this work, the author gives a complete characterization ... A regime-switching geometric Brownian motion is used to model a geometric Brownian motion with its coefficients changing randomly according to a Markov chain.In this work, the author gives a complete characterization of the recurrent property of this process. The long time behavior of this process such as its p-th moment is also studied. Moreover, the quantitative properties of the regime-switching geometric Brownian motion with two-state switching are investigated to show the difference between geometric Brownian motion with switching and without switching. At last, some estimates of its first passage probability are established. 展开更多
关键词 ERGODICITY Regime-switching diffusions Lyapunov functions First passageprobability
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Morse Potential in the Momentum Representation
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作者 孙国华 董世海 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第12期815-818,共4页
The momentum representation of the Morse potential is presented analytically by hypergeometric function. The properties with respect to the momentum p and potential parameter β are studied. Note that [q2(p)l is a n... The momentum representation of the Morse potential is presented analytically by hypergeometric function. The properties with respect to the momentum p and potential parameter β are studied. Note that [q2(p)l is a nodeless function and the mutual orthogonality of functions is ensured by the phase functions arg[(p)], It is interesting to see that the [~ (p)[ is symmetric with respect to the axis p = 0 and the number of wave crest of [ (p)[ is equal to n + 1. We also study the variation of ]k(p)l with respect to . The arnplitude of |ψ(p)] first increases with the quantum number n and then deceases. Finally, we notice that the discontinuity in phase occurs at some points of the momentum p and the position and momentum probability densities are symmetric with respect to their arguments. 展开更多
关键词 morse potential momentum representation phase discontinuity
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First-Principles Study of Geometries,Stabilities and Electronic Properties of Ca_2Sin_(n=1–11) Clusters
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作者 张帅 王爱华 +2 位作者 高振海 卢成 李根全 《Communications in Theoretical Physics》 SCIE CAS CSCD 2014年第1期106-114,共9页
The equilibrium geometries, relative stabilities, and electronic properties of Ca2Sin (n = 1-11) clusters have been systematically investigated by using the density function theory at the 6-311G (d) level The opti... The equilibrium geometries, relative stabilities, and electronic properties of Ca2Sin (n = 1-11) clusters have been systematically investigated by using the density function theory at the 6-311G (d) level The optimized geometries indicate that the most stable isomers have three-dimensional structures for n = 3-11. The electronic properties of Ca2 Sin (n = 1-11) dusters axe obtained through the analysis of the natural charge population, natural electron configuration, vertical ionization potential, and vertical electron affinity. The results show that the charges in corresponding Ca2Sin clusters transfer from the Ca atoms to the Sin host. Based on the obtained lowest-energy geometries, the size dependence of cluster properties, such as averaged binding energies, fragmentation energies, second-order energy differences, HOMO- LUMO gaps and chemical hardness, are deeply discussed. 展开更多
关键词 Ca2Sin cluster density functional theory geometrical structures electronic properties
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