具有(6~3.10~3)(6~3)拓扑结构的三维Zn~(2+)配位聚合物的合成及结构研究

以4,4′-联吡啶(bipy)、2,5-二巯基-1,3,4-三噻唑(H2SSS)为桥联配体,水热法合成了一新颖的三维结构配位聚合物[Zn2(SSS)2(bipy)]n(1),并用元素分析、IR和差热分析对配合物进行了表征,X-射线单晶衍射确定了配合物的结构。在该配合物中,每个配阴离子SSS2-桥联3个Zn2+,同时每个Zn2+连接3个配体构成一个与ab平面平行的二维网状结构,相邻网状结构再通过4,4′-bipy连接构成三维微空结构。     

Fatigue Life Prediction of the Metro Bolster Beam under Complex Operating Conditions

Sixteen operating conditions were determined by the standards JIS-7105 and JIS-7106. The strength under complex operating conditions was calculated with HyperWorks and the strength analysis confirmed eight dangerous points of the metro bolster beam. Since the metro did not consider the impact of traffic lights and sudden road conditions, the load spectra at eight dangerous points were established by counting the running time,passenger flow,site layout,site quantity and turning situations. The fatigue life of the metro bolster beam was projected by the von Mises stress method and the critical plane method. The results of these two methods revealed that the maximum damage occurred at the dangerous point 7,and the fatigue life based on the critical plane method was shorter than that based on the von Mises stress method.Since the McDiarmid model considered the effect of the magnitude and direction of the normal stress and the amplitude of the shear stress,it is closer to the actual situations of the metro. Hence,the McDiarmid model based on the critical plane method is more reasonable,and the method of fatigue life prediction is also suitable to the metro bolster beam of other lines.