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1.
基于多体展式方法所导出的NiH2(3Δg)解析势能函数,用准经典的Monte-Carlo轨迹法对Ni(3F4)+H2(X1Σ+g,v=j=0)的分子反应动力学过程进行了计算.结果表明此反应的主产物为交换反应Ni(3F4)+H2(X1Σ+g,v=j=0)→NiH(X2Σ+,v′,j′)+H(2Sg)的NiH(X2Σ+,v′,j′),没有发现NiH2(3Δg)络合物,从反应截面σr与相对平动能Et的关系发现该反应为有阈能反应,阈能值为33.87 kJ/mol.同时,由于Ni的质量比氢的大,发生的是直接碰撞,产物散射角分布是向前的.  相似文献   

2.
使用经典轨迹法研究了反应C(^3Pg)+SiO(X^1∑^+,V=0,J=0)碰撞轨迹.碳化硅合成反应C(^3Pg)+SiO(X^1∑^1,V=0,1;J=0)→SiC(X^1∑^1)+O(^3Pg)存在阈能,反应截面存在一个极大值和最佳反应能量.在SiC最佳产率区,通过反应物的振动激发并不能使SiC产率明显提高,基态下SiC合成反应的最佳能区为该反应的最佳产率区.  相似文献   

3.
运用半刚性振转靶(semirigid vibrating rotor target-SVRT)模型和含时波包法(TDWP method),对O(3^P) CH4→CH3 OH反应体系进行了含时量子动力学计算,给出了该体系对应于不同初始态的反应几率,通过对j=0时,v=0,1的反应几率的计算,看出H—CH3的振动激发,极大地提高了反应几率,而反应阈能明显降低,说明反应分子的振动能对分子的碰撞反应有重要贡献,而对于v=0时,j=0,1,2,3的反应几率的计算,得出转动量子数j的增大,也会使反应几率有较大的提高,但反应阈能基本不变。此外,通过对j=5时,K=0—2,n=0和j=5时K=2,n=0—2的反应几率的计算,研究和分析了该反应的空间立体效应。  相似文献   

4.
:在用多体项展式方法建立HDO分子解析势能函数的基础上,用准经典轨线(Quasi-classical trajectory,QCT)方法,研究了碰撞体系D+OH(A^2∑+,u=0,j=0)在5个产物通道上的动力学特点.结果表明:即使碰撞能量较低,D+OH(A^2∑+,u=0,j=0)也不能形成长寿命络合物;交换反应D+OH→DH+O和D+OH→DO+H能在较宽的碰撞能量范围内发生,且均为无阈能的放热反应,但其发生的几率不同,前者的反应截面明显大于后者;当碰撞能量进一步增大时(例如达到334.72kJ/mol),碰撞将诱导体系完全离解.  相似文献   

5.
当丢番图方程∑i=1^n∑j=1^naijyiyj=0有一组非平凡的整数解y1^*,y2^*,…,yn^*(yn^*≠0)时,给出了方程∑i=1^n∑j=1^n(aij)/xixj=0满足(x1,x2,…,xn)=1的全部整数解的公式.  相似文献   

6.
基于多体展式方法所导出的OH2分析势能函数,用准经典的Monte Carb轨迹方法对O(1D) H2(X1∑ g)(v=0,j=0)→H OH(v′,j′)的分子反应动力学过程进行了计算.得到了该反应的产物分布情况和各通道之间的竞争,研究了相对平动能与反应截面的关系以及相对平动能对反应几率的作用,同时对该反应的微观机理也作了一定的探讨.获得了一些较有意义的结果.  相似文献   

7.
使用SAC/SAC—CI和D95++**、6—311++g**及cc—PVTZ基组,分别对D2分子的基态X^1∑6^+、第二激发态B^1∑u^+和第三简并激发态CI见的平衡结构和谐振频率进行优化计算.对所有计算结果进行比较,得出cc—PVTZ基组为最优基组.运用cc—PVTZ基组和SAC方法对基态X^1∑g^+、SAC—CI方法对激发态B^1∑u^+和C^1∏u进行单点能扫描计算,并用正规方程组拟合Murrell—Sorbie函数,得到相应电子态的势能函数解析式,由得到的势能函数计算了与X^1∑g^+、B^1∑u^+和C^1∏u态相对应的光谱常数,结果与实验数据较为一致.  相似文献   

8.
求解矩阵方程AX+XB=F是控制论面临的重要计算 [1].本文定理1给出任意插值条件下插值多项式的解析表达式;在定理1的基础上,定理2给出矩阵方程AX+XB=F解的解析表达式为X=∑s2j=1∑vj-1q=0(-1) qq  相似文献   

9.
O(3P)+CH4→CH3+OH反应的半刚性振转靶计算   总被引:2,自引:1,他引:2  
运用半刚性振转靶(semirigid vibrating rotor target-SVRT)模型和含时波包法(TDWP method), 对O(3P)+CH4→CH3+OH反应体系进行了含时量子动力学计算, 给出了该体系对应于不同初始态的反应几率. 通过对j = 0时, v = 0, 1的反应几率的计算, 看出H-CH3的振动激发, 极大地提高了反应几率, 而反应阈能明显降低, 说明反应分子的振动能对分子的碰撞反应有重要贡献. 而对于v = 0时, j = 0, 1, 2, 3的反应几率的计算,得出转动量子数j的增大, 也会使反应几率有较大的提高, 但反应阈能基本不变. 此外, 通过对j = 5时, K = 0-2, n = 0和j = 5时K = 2, n = 0-2的反应几率的计算, 研究和分析了该反应的空间立体效应.  相似文献   

10.
探讨Diophantus方程∑I=0^n(x i)^2=y^2在n≤50下的正整数解问题,得到了以下结果:Diophan-tus方程∑I=0^n(x i)^2=y^2在n≤50下有正整数解的充要条件为n∈{1,10,22,23,25,32,46,48,49}。  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.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

14.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

15.
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   

16.
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   

17.
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   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
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   

20.
The non-orthogonal localized molecular orbital(NOLMO)is the most localized representation of electronic degrees of freedom.As such,NOLMOs are thus potentially the most efficient for linear scaling calculations of electronic structures for large systems.However,direct ab initio calculations with NOLMO have not been fully implemented and widely used,partly because of the slow convergence issue in the optimization of NOLMO.We devel-  相似文献   

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