冻融环境下钢筋混凝土粘结性能研究现状

基于国内外关于钢筋混凝土结构在冻融循环作用下钢筋和混凝土之间粘结性能的研究进展,重点总结了在冻融条件下以及冻融和腐蚀、荷载等因素共同作用下钢筋混凝土粘结滑移性能的研究进展和现状,综合分析了现有的研究成果,在此基础上提出了一些不足和建议。

On Maps Preserving the Spectrum on Positive Cones of Operator Algebras

We consider the spectrum-preserving maps on positive definite cones of C*-algebras or von Neumann algebras. We first introduce some basic properties of Jordan isomorphism. Then, we study the additively spectrum preserving property and the multiplicatively spectrum-preserving property, and prove that these maps can be characterized by Jordan isomorphisms between C*-algebras.