湖南省各地市州居民生活水平比较分析

本文结合恩格尔系数研究居民生活水平的优点，采用聚类分析法与主成分分析法对2004年湖南省各地市州居民生活水平进行比较分析，给出了这些城市居民生活水平的综合得分及其排序，从而更真实地衡量湖南省各地市州居民生活水平．     

2-连通无爪图的连通因子

若图G不含有同构于K1,3的导出子图,则称G为一个无爪图.令a和b是两个整数满足2≤a≤b.本文证明了若G是一个含有[a,b]因子的2连通无爪图,则G有一个连通的[a,b 1]因子.     

Properties of the solution set of nonlinear evolution inclusions

In this paper we examine nonlinear, nonautonomous evolution inclusions defined on a Gelfand triple of spaces. First we show that the problem with a convex-valued,h*-usc inx orientor fieldF(t, x) has a solution set which is anR _δ-set inC(T, H). Then for the problem with a nonconvex-valuedF(t, x) which ish-Lipschitz inx, we show that the solution set is path-connected inC(T, H). Subsequently we prove a strong invariance result and a continuity result for the solution multifunction. Combining these two results we establish the existence of periodic solutions. Some examples of parabolic partial differential equations with multivalued terms are also included. This work was done while the authors were visiting the Florida Institute of Technology.     

2-控制数和连通2-控制数相等的图(英文)

任意一个图G =(V ,E) ,S是V(G)的子集 ,如果对每一个顶点u∈V-S都存在顶点v∈S ,使得d(u ,v) ≤ 2 ,则称S为G的一个 2 控制 .称最小的 2 控制集的顶点个数为G的 2 控制数 ,记为γ2 (G) .如果G的一个 2 控制集S的生成子集〈S〉是一个连通图 ,则称S为G的一个连通 2 控制集 .称最小的连通 2 控制集的顶点个数为G的连通 2 控制数 ,记为γc2 (G) .本文论述了树和单圈图中 2 控制数和连通 2 控制数相等的充分必要条件 .     

Non-noetherian regular rings of dimension 2

We study connected, not necessarily noetherian, regular rings of global dimension 2.

     

关于具分形边界连通区域上的谱渐近及弱Weyl-Berry猜想

本文研究了连通分形鼓上的谱渐近，对满足“切口”条件的连通分形鼓以及一类自然连通的分形鼓，分别证明了弱Weyl－Berry猜想是成立的.     

凹叶厚朴各部位挥发油成分比较研究

采用顶空固相微萃取(HS-SPME)提取凹叶厚朴不同部位的挥发油成分,气相色谱-质谱(GC-MS)分析其组成.结果显示:根鉴定出19个化合物,其中4(14),11-桉叶二烯(26.04％),(1S-顺)-1,4-二甲基-7-(1-甲基亚乙基)-奠(24.94％),石竹烯(9.41％),β-桉叶醇(7.28％)为主要成分...     

Bounds on the connected domination number of a graph

A subset S$S$ of vertices in a graph G=(V,E)$G=(V,E)$ is a connected dominating set of G$G$ if every vertex of V?S$V?S$ is adjacent to a vertex in S$S$ and the subgraph induced by S$S$ is connected. The minimum cardinality of a connected dominating set of G$G$ is the connected domination number _γc(G)${\gamma }_c\left(G\right)$. The girth g(G)$g\left(G\right)$ is the length of a shortest cycle in G$G$. We show that if G$G$ is a connected graph that contains at least one cycle, then _γc(G)≥g(G)−2${\gamma }_c\left(G\right)\ge g\left(G\right)-2$, and we characterize the graphs obtaining equality in this bound. We also establish various upper bounds on the connected domination number of a graph, as well as Nordhaus–Gaddum type results.     

X射线荧光光谱法测定黏土中的主次组分

采用熔融玻璃片制样,选用标准样品,以经验α系数和散射线内标法校正元素谱线重叠干扰和基体效应,使用ZSX Primus Ⅱ X射线荧光光谱仪对黏土样品中的Al₂O₃、SiO₂、Fe₂O₃、CaO、MgO、K₂O、Na₂O、MnO、P₂O₅、TiO₂、Cu、Cr等组分进行测定,分析结果与标准值和化学值相吻合,12次测定的相对标准偏差小于10%.