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1.
证明了Seoud等当k≥3时C3与C2k的不相交并C3∪C2k为调和图的猜想,并扩展该结果,证明了C5∪C2k(k≥2)是调和图;给出猜想C2j+1∪C2k(j≥1,k≥2且(j,k)≠(1,2)是调和图。证明了幂图P^4n(8≤n≤17)与P^5n(14≤n≤17)是调和图,否定了Seoud等关于当且仅当1≤k≤3时P^kn(1≤k≤n-1)是调和图的猜想。给出了相反的猜想:当n≤n0(k)时P  相似文献   

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设图G是一个n阶简单图,G中的一个圈C称为Dλ一圈,如果G/V(C)的每个连能分支的阶都小于λ。当G是3-连通图,且有NCλ(G)≥n+4/2-2λ时,G含有Dλ-圈或G是Petersen图。  相似文献   

4.
本文将给出所有能量不超过4的连通简单偶图,并给出关于图的能量与其边的个数的一个不等式。  相似文献   

5.
所谓齿轮图 G_(2n+1)是将轮图 W_(n+1)轮缘的每一条边上再加上一个点所得到的图,在本文中我们证明了齿轮图G_2n+1是协调图。  相似文献   

6.
张宣昊  陆伟成 《科学技术与工程》2011,(26):6249-6252,6261
根据一些已知的紧图构造出两类新的紧图。证明了在一定条件下连通正则紧图的联图为紧图,两个连通正则紧图之间再加一条边仍为紧图。  相似文献   

7.
本文给出了常见的简单双原子分子严格意义上的各类分子轨道图,并从周期律出发,讨论了分子轨道图与物质结性质间的联系。  相似文献   

8.
本文给出了无爪图是顶点泛圈图的一个充分条件,推广了Brocrsma和Veldman的两个结论。  相似文献   

9.
本文对圈和树的二次幂图的 Hamilton 连通性进行了研究。  相似文献   

10.
一类极大临界h连通图   总被引:4,自引:0,他引:4  
讨论了最小度等于3h/2-1的极大临界h连勇图的性质,并给出这类图的构造方法。  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.
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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
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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<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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