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1.
利用大D函数的正交归一化关系和两个大D函数的耦合规则,以最简单的单粒子乘积波函数为例,给出了2个、3个乃至多个粒子波函数的角动量投影算符的矩阵元与CG系数的关系.论证了CG系数和积分两种角动量投影算符矩阵元计算方法的一致性和各自的优缺点,讨论了角动量投影算符矩阵元的性质.  相似文献   

2.
常规的积算符法不能获得自旋为1/2InS(n≥2)体系的密度算符在交叉极化和各向同性混合过程随时间演化的解析解。作者提出用投影算符法解决此问题,并以I2S体系的交叉极化过程为列分析了获得无相位畸变和强度失真NMR谱的方法。  相似文献   

3.
按照离子型分子的空间对称性和自旋对称性以及离解度的大小,选择适当的组态函数,用投影算符消除其他多重态的污染,采用组态互作用法计算了N^+2的X^2Σ^+g态、B^2Σ^+u态和C^2Σ^+u的能量及第一,第二负带系的振子强度,计算值与实验值吻合。  相似文献   

4.
对理想的具有自旋1/2和赝旋1/2两自由度费米气体系统的两体纠缠进行研究.结果表明:态空间的扩大,导致系统不超过4个费米子间的两体纠缠表现出类似于自旋1/2自由度的费米气体系统中两费米子间的纠缠分布,而完全不同于其对应的多个费米子间的约化两体纠缠分布;系统两费米子间纠缠存在的相对距离比单个自旋1/2自由度系统时增加了约1.7倍,并且由于两费米子间任一自由度的子纠缠始终为零,因此其中一个自由度的两费米子的子纠缠或量子关联来自于系统的相互作用.  相似文献   

5.
利用从头算非限制Hartree-Fock方法,分别计算了甲氧基取代的对一半醌和对一氢化半醌系列的不同组份的自旋密度,用经验的McConnell关系估算了电子自旋共振(ESR)实验测定的质子各向同性超精细分裂。结果表明,理论计算符合较好,经验的加和性规则不灵。为了解释醌环上两个相邻甲氧基取代基的ESR的异常测定值,必须考察溶剂效应。利用投影算符技巧讨论了有关解释得自非自旋本征态的非限制Hartree-Fock波函数的自旋密度的基本问题。得到的各体系的UHF波函数几乎全为纯的双重态。  相似文献   

6.
采用改进的线性组合算符方法,研究了Rashba效应影响下半导体量子点中强耦合极化子的光学声子平均数.导出在电子-体纵光学声子(LO)强耦合时抛物量子点中极化子的光学声子平均数、振动频率、相互作用能和有效质量随受限强度和Rashba自旋-轨道耦合常数的变化.数值计算结果表明Rashba自旋-轨道相互作用使极化子的有效质量、基态能分裂为上下两支,随耦合常数的增加极化子基态能量、有效质量表现为增加和较少两种截然相反的情形;Rashba自旋-轨道相互作用影响下强耦合极化子的光学声子平均数随量子点的受限强度、电子声子耦合强度增大而增大,极化子的相互作用能随受限强度的增加先急剧增加,当达到极值后随受限强度的增加而急剧减少.  相似文献   

7.
若轻子由3个自旗为1/2的亚夸克组成,则除了存在自旋S1/2的轻子基态外,在受激情况下,也将出现S=3/2的激发态,两者的质量差与亚夸克构成轻子的对称性质及亚夸克与双夸克的相互作用密切相关。  相似文献   

8.
若轻子由3个自旋为1/2的亚夸克组成,则除了存在自旋S=1/2的轻子基态外,在受激情况下,也将出现S=3/2的激发态.两者的质量差与亚夸克构成轻子的对称性质及亚夸克与双夸克的相互作用势密切相关.  相似文献   

9.
考虑Rashab自旋-轨道相互作用对半导体量子点中极化子基态能量的影响.采用LLP中耦合的方法处理了电子-声子相互作用.结果表明由于Rashba效应的影响使得极化子的基态能量分列为上下两支而且Rashba自旋-轨道相互作用能与总的基态能及其它能量成分间的比例关系,随电子波矢K变化非常显著.Rashba自旋-轨道相互用作使得量子点中极化子基态能量在无任何外磁场的情况下发生分裂,所以完全不同于强磁场影响下的简单Zeeman效应,然而,自旋-轨道相互作用引起的分裂有时掺杂着Zeeman分裂。因此它引起的分裂属于复杂分裂.声子对总能量的贡献为负,由于声子的存在极化子争裂能较裸电子更为稳定.  相似文献   

10.
对于具有晶格结构的固体、利用在相对论狄喇克方程的非相对论极限下得到的电子自旋-轨道相互作用,推导出自旋涨落一声子相互作用。利用此相互作用推导出自旋磁化率、电荷极化率、声子格林函数的一组自洽方程。然后,又讨论了自旋和电荷密度涨落的共存性及其对高温超导的影响。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

19.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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