应gg999策略手机白菜的邀请，南开大学李学良教授将于近期访问我院，并做以下系列学术报告：

        时间：2017.6.24（周六）下午2:00-3:00

        地点：理科楼407

        题目：Constructions of graphs and trees with partially prescribed spectrum

        Abstract: It is shown how a connected graph and a tree with partially prescribedspectrum can be constructed. These constructions are based on a result of Salez that every totally real algebraic integer is an eigenvalue of a tree. Our result implies that for any (not necessarily connected) graph, there is a tree such that the characteristic polynomial of the graph divides the characteristic polynomial of the tree. Some open problems will also be presented in this talk. This is a joint work with Ivan Gutman and Wasin So.

        报告人简介：李学良教授，博士生导师。现任南开大学组合数学中心副主任，中国组合数学与图论学会理事长，天津市工业与应用数学学会理事长，天津市数学会副理事长，中国数学会理事，中国工业与应用数学学会理事。《Discrete Applied Mathematics》、《Graphs and Combinatorics》和《MATCH Communications in Mathematical and in Computer Chemistry》等10余种国际杂志编委，《应用数学学报（中、英文版）》和《数学进展》国内杂志编委。主要从事图论与组合优化、化学图论、计算机科学理论方面的研究工作，在所研究领域的多种重要学术期刊上发表论文300余篇，4500余篇次被国内外同行学者的论著引用，在国外出版著作9部。

        欢迎感兴趣的师生参加！