图的联结数与分数k-消去图

设G是一个图,若对于图G的任一条边e,G-e都存在一个分数k-因子,则称G是一个分数κ-消去图.若k=2,则称分数κ-消去图为分数2-消去图.本文证明了当bind(G)≥2,并且6(G)≥3时,G是分数2-消去图.     

Moving and Interaction of Compact-like Pulses in Klein-Gordon Lattice System

We study the moving and interaction of the compact-like pulses in the system of an anharmonlc lattice with a double well on-site potential by a direct algebraic method and numerical experiments. It is found that the localization of the compact-like pulse is rClated to the nonlinear coupling parameter Cnl and the potential barrier height Vo of the double well potential. The velocity of the moving compact-like pulse is determined by the linear coupling parameter Cl, the localization parameter q (the nonlinear coupling parameter Cnl) and the potential barrier height Vo.Numerical experiments demonstrate that appropriate Cl is not detrimental to a stable moving of the compact-like pulse.However, the head on interaction of two compact-like pulses in the lattice system with comparatively small Cl leads to the appearance of a discrete stationary localized mode and small amplitude nonlinear oscillation background, while moderate Cl results in the emergence of two moving deformed pulses with damping amplitude and decay velocity and radiating oscillations, and biggish Cl brings on the appearing of four deformed kinks with radiating oscillations and different moving velocities.     

Theoretical Studies on the M-M Bonding in Complexes [M2Cl4L2] and [M2Cl7L]- （M = Mo, Re; L = Ph2Ppy, （Ph2P）2py）

The structures of complexes [MⅡ2Cl4L2] and [MⅢ2Cl7L]- (M = Mo, Re; L = Ph2Ppy, (Ph2P)2py) were calculated by using density functional theory (DFT) PBE0 method. Based on the optimized geometries, the natural bond orbital (NBO) analyses were carried out to study the nature of Re-Re and Mo-Mo bonds. The conclusions are as follows: the M-M distances in two-Ph2Ppy or (Ph2P)2py complexes [MⅡ2Cl4L2] are shorter than those in mono-Ph2Ppy or (Ph2P)2py complexes [MⅢ2Cl7L]- due to the double bridged N-C-P interactions. For singlet of all complexes, there is ReⅢ-ReⅢ or MoⅡ-MoⅡ quadruply bond in complex [Re2Cl7L]- or [Mo2Cl4L2], while only ReⅡ-ReⅡ or MoⅢ-MoⅢ triply bond in complex [Re2Cl4L2] or [Mo2Cl7L]-. The most stable spin state of 2 and 6, triplet, only contains triple ReⅢ-ReⅢ bond. Because the LPCl → BD*Re-Re delocalizations weaken the Re-Re bond, the distance of ReⅢ-ReⅢ quadruple bonds in [Re2Cl7L]- is slightly longer than that of ReⅡ-ReⅡ triple bonds in [Re2Cl4L2]. Moreover, due to the delocalizations from the lone pair electrons of the remaining P' atom to the M-M antibonding orbitals, the M-M distance in (Ph2P)2py complexes is slightly longer than that in Ph2Ppy complexes.     

信用违约联结票券的定价

本文从定义信用违约联结票券出发,介绍了JarrowandTurnbul(1995)违约强度模型。然后在该模型的基础上,针对不同的公司,假设违约时间独立同服从指数分布且与利率期间结构独立,分别就t=0与0     

液相体系晶须生长机理:拓展的ACP机制

晶须生长机制一直备受关注,然而"晶须到底是怎样生长为条状的?"这一科学问题始终未能得到解决.传统晶须生长机制不适用于液相体系晶须生长.本文试图提出液相体系晶须生长机制应为拓展的ACP(Anion Coordination Polyhedron)机制.因为传统的晶须生长机制未能解释液相体系晶须的生长形态,也未能解释晶须的多样性以及指导人工可控晶须生长.拓展的ACP生长机制克服了这些问题,并有效地指导人工晶须生长.     

Complete Synchronization in Coupled Chaotic HR Neurons with Symmetric Coupling Schemes

Chaos synchronization in an array of coupled chaotic neurons with symmetric coupling is investigated. A criterion for the stability of the synchronization manifold is deduced by transforming the variational equation of the coupled system into a block diagonal one, and the critical coupling strengths for synchronization in different coupled cases are given. As examples for illustration, the HR neurons with the open-ended （i.e. chain）, ring, star and all-to-all （i.e. global） coupling schemes are considered. It is shown that the coupling scheme plays an important role in synchronization and information transmission of neurons.     

挠性联结双体卫星的混沌运动

本文讨论一挠性联结双刚体航天器模型，通过计算其动力学方程异宿轨道稳定流形与不稳定流形的相交角方法，给出其稳定流形与不稳定流形横截相交的判据，并通过Ｐｏｉｎｃａｒｅ截面的计算，证明其产生混沌运动的可能性。     

图的联结数与分数κ-消去图

设G是一个图,若对于图G的任一条边e,G-e都存在一个分数k-因子,则称G是一个分数k-消去图.若k=2,则称分数k-消去图为分数2-消去图.本文证明了当bind（G）≥2,并且δ（G）≥3时,G是分数2-消去图.     

浙西南松叶蕨分布区的群落结构与生境特征

松叶蕨（Psilotumnudum）是裸蕨类松叶蕨属孑遗植物，由于分布范围的急剧缩小，现已处于极度濒危状态．对分布于浙江缙云的松叶蕨的自然环境进行了野外调查，测定群落的总体方差比率及X^2统计量等种间联结性指标，并测定其土壤含水量、有机质含量、pH值，以及植株和土壤中的K、Ca、Mg、Fe、Zn、Cu、Mn、Na、Al、Pb、Cd等元素含量．结果表明：松叶蕨群落种类丰富，植被类型的次生特征明显．松叶蕨与极少数种群的种间联结性显著，与大部分种群种间联结性不显著，松叶蕨在群落中具有很大的独立性或随机性．松叶蕨多分布于岩石缝隙或附生在树干上，群落土壤含水量在12．8％～24．6％，pH值4．75～5．18，电导率0．236～0．089mS·cm^-1，有机质含量3．60％～6．08％；松叶蕨对K、Na、Ca和Mg的需要量较高，对Cu、Pb和Cd等重金属元素的富集能力不显著．