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1.
用从头计算方法计算了FC(O)SSC(O)和ClC(O)Cl分子的结构,势能分布及振动谱,结果表明:FC(O)SSC(O)具有两种稳定构型(I和II)。在气相中构型I最稳定,具有C2点群对称性,构型II属于C1点群;ClC(O)SSC(O)Cl仅仅具有一定稳定构型,属于C2点群利用势能分布及同位素替代方法确定了振动归属,计算得到的振动频率结果和实验很好地一致。  相似文献   

2.
全面论述了瘦C/S计算的背景及其工作原理,在深入分析水泥企业产品销售特点的基础上,提出了开发大型水泥企业在线式销售网络系统的基本要求,并在最后给出了瘦C/S计算的应用实例———基于瘦C/S计算的葛洲坝水泥厂在线式销售网络系统。  相似文献   

3.
偏心率对空间偏心管状接头应力集中的影响   总被引:1,自引:0,他引:1  
修订了空间管状接头应力分析的计算机程序SAMTJ,使其能用来计算空间偏心管接头的应力集中系数(SCF).然后以偏心DT型接头为例,计算了可能热点的SCF,并探讨了偏心率对SCF的影响.  相似文献   

4.
运用Gaussian94程序,由从头计算方法计算了基态SiC(x^1∑^+)分子的平衡结构和离解能,利用单点计算的结果,采用Murre-Scorbie函数形式,拟合出了SiC分子的分析热能函数,并计算出SiC分子的光谱常数ωe,ωeXe,Be,αe的值。  相似文献   

5.
提出用电荷控制法研究a-SiCCD电荷转移特性的理论模型,通过引入平均场效应迁移率的概念,推导出计算a-SiCCD电荷转移损失率的解析解,理论计算与实验结果符合较好.该模型可以较好地反映热扩散、自感应电场和边缘电场的漂移机制对a-SiCCD电荷转移特性的影响,分析结果表明,a-SiCCD的电荷的转移主要是受电场漂移作用控制.  相似文献   

6.
采用马尔可夫过程、排队理论对C/S计算模式基础上的5种计算模式进行系统效率、可靠性、数据一致性的定量分析,该分析为用户建立实际的C/S系统环境,并为不同任务选择合适的计算模式提供了理论依据。  相似文献   

7.
提出用电荷控制法研究a-SiCCD电荷转移特性的理论模型,通过引入平均场效应迁移率的概念,推导出计算a-SiCCD电荷转移损失率的解析解,理论计算与实验结果符合较好,该模型可以较好地反映热扩散、自感应电场和边缘电场的漂移机制对a-SiCCD电荷转移特性的影响,分析结果表明,a-Si CCD的电荷的转移主要是受电场漂移作用控制。  相似文献   

8.
半导体硅桥点火器的设计初探   总被引:4,自引:0,他引:4  
作者从半导体硅桥点火的机理出发,得到了实现SCB点火的基本关系式并计算了SCB在熔化,气化过程中与温度无关的比热。作者还对实现SCB点火有关参数的取值进行讨。经过关系式的分析及计算证明与实验观测相符,其结果为SCB的设计,制造和应用具有实用价值。  相似文献   

9.
介绍了在超临界流体(SCF)-固体(S)物质体系平衡溶解度计算中采用的一些方法,包括状态方程法、活度系数法和分子缔合法.论述了SCF-S体系中溶解度计算的研究进展。  相似文献   

10.
固体物质在超临界流体中的溶解度研究进展   总被引:1,自引:0,他引:1  
介绍了在超临界流体(SCF)-固体(S)物质体系平衡溶解度计算中采用的一些方法,包括状态方程法、活度系数法和分子缔合法。论述了SCF-S体系中溶解度计算的研究进展。  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.
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   

18.
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   

19.
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   

20.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

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