Sufficient Conditions for a Digraph to be Supereulerian

A (di)graph is supereulerian if it contains a spanning eulerian sub(di)graph. This property is a relaxation of hamiltonicity. Inspired by this analogy with hamiltonian cycles and by similar results in supereulerian graph theory, we analyze a number of sufficient Ore type conditions for a digraph to be supereulerian. Furthermore, we study the following conjecture due to Thomassé and the first author: if the arc‐connectivity of a digraph is not smaller than its independence number, then the digraph is supereulerian. As a support for this conjecture we prove it for digraphs that are semicomplete multipartite or quasitransitive and verify the analogous statement for undirected graphs.     

Strong edge-coloring for planar graphs with large girth

A strong edge-coloring of a graph $G=(V,E)$ is a partition of its edge set $E$ into induced matchings. Let $G$ be a connected planar graph with girth $k\ge 26$ and maximum degree $\Delta$. We show that either $G$ is isomorphic to a subgraph of a very special $\Delta$-regular graph with girth $k$, or $G$ has a strong edge-coloring using at most $2\Delta +\lceil \frac{12(\Delta -2)}{k}\rceil$ colors.     

Some necessary and sufficient conditions for Hypercyclicity Criterion

We give necessary and sufficient conditions for an operator on a separable Hilbert space to satisfy the hypercyclicity criterion. This paper is a part of the second author’s Doctoral thesis, written at Shiraz University under the direction of the first author.     

Sparse graph certificates for mixed connectivity

We give a short proof for the Mixed Connectivity Certificate Theorem of Even, Itkis and Rajsbaum and provide an upper bound on the edge number of a certificate of local T-mixed connectivity up to k.     

On Best Approximations from RS-sets in Complex Banach Spaces

The concept of an RS-set in a complex Banach space is introduced and the problem of best approximation from an RS-set in a complex space is investigated. Results consisting of characterizations, uniqueness and strong uniqueness are established,     

On the degree of convergence of lemniscates in finite connected domains

For an arbitrary bounded closed set E in the complex plane with complement Ω of finite connectivity, we study the degree of convergence of the lemniscates in Ω.     

用于强磁场的快响应真空规的研制进展

研制了能在强磁场、强干扰环境下工作的快响应真空电离规(快规),用于对HL 2A装置偏滤器室和等离子体附近的中性粒子密度和通量进行原位测量。介绍了快规的结构、工作原理、设计要点以及实验结果。在无磁场的情况下,快规对气体压强的测量范围为6.4×10-6～0.15Pa,在1×10-5～0.15Pa范围内,快规收集极离子流与发射电子流之比与气压保持良好线性关系;在0 15T的磁场下,快规的规管常数未发生显著变化,在规管对称轴与磁力线的夹角小于15o时,规管常数的变化小于10%。     

PURIFICATION OF L-METHIONINE AND N-ACETYL-D-METHIONINE FROM THE MIXTURE OF ENZYMATICALLY DEACYLATED N-ACETYL-DL-METHIONINE

1. INTRODUCTION Methionine, namely 2-amido-4-thiomethyl butyric acid with a structure of CH3SCH2CH2CHCOOH, is one of the essential amino acids and has two natural enantionmers, D and L-methionine. The mixture of L- and D-isomers can be used as analeptics or nutritive additives to maintain the equilibrium of amino acids of feed [1,2]. L-methionine can release active methyl and accelerate the synthesis of choline, which further speeds up the conversion of the lipid accumulated in liv…     

若干图的点强全染色(英文)

对图G及正整数k，映射f：满足：（1）任意e1，e3，如果e1，e2是相邻或相关联的，则有；（2）对u，v，w（G）有，则称f为G的一个k-点强全染色，并且K|G的社点强全染色称为G的点强全色数．本文讨论了一些特殊困的点强全色数，并提出了一个猜想：若G为每一分图的阶数不小于6的图，则（G），其中（G）为本文中定义的一新参数．     

Some Notes about Tanaka''''s Equation

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