企业社会责任对可持续发展的影响——基于钢铁类上市公司的实证研究

以上市钢铁公司为样本,构造出持续发展能力的相关变量,通过2005～2010年的年报数据,运用多元回归方法,分析了钢铁公司履行社会责任对持续发展能力的影响。结果显示:企业对投资者履行社会责任对持续发展能力影响显著。     

崇启大桥曲线形变截面钢箱梁梁段制造工艺技术

介绍了崇启大桥曲线形变截面钢箱梁梁段在制造过程中所采用的制造工艺技术,为同类型桥梁制造提供参考。     

钢框架柱计算长度系数的有限元分析

柱计算长度法是钢框架稳定设计的常用方法,顶底角钢连接梁柱节点是一种典型的半刚性梁柱节点。采用抗弯弹簧模拟梁柱节点连接的半刚性,得到顶底角钢半刚接形式对钢框架柱计算长度系数的影响。运用有限元分析方法对其进行对比分析。     

钢框架稳定承载力的有限元分析

钢框架的稳定承载力受多方面的因素影响,除梁柱的线刚度外,主要因素有节点连接刚度、荷载条件、同层间相互作用等,运用有限元分析方法对几项因素研究,得出其对钢框架稳定的影响程度。     

罐区钢带浮子液位变送器的改造

文章结合作者的工作实践 ,论述了用 PLC改造罐区钢带浮子液位变送器的方法 ,并从技术角度和经济效益上分析了这种方法的可行性。     

Effect of direct quenching on microstructure and mechanical properties of medium-carbon Nb-bearing steel

The influence of direct quenching （DQ） on microstructure and mechanical properties of 0.19C-1.7Si-1.0 Mn-0.05Nb steel was studied. The microstructure and mechanical properties of reheat quenched and tempered （RQ＆T） steel plate were compared with those of direct quenched and tempered （DQ＆T） steel plates which were hot rolled at different finish rolling tem-peratures （1173 K and 1123 K）, i.e., recrystallization-controlled-rolled direct-quenched （RCR＆DQ） and controlled-rolled direct-quenched （CR＆DQ）, respectively. The strengths generally increased in the following order： RQ＆T〈RCR＆DQ＆T〈 CR＆DQ＆T. Strength differences between the CR＆DQ＆T and RQ＆T conditions as high as 14% were observed at the tempered temperature of 573 K. The optical microscopy of the CR＆DQ＆T steel showed deformed grains elongated along the rolling direction, while complete equiaxed grains were visible in RQ＆T and RCR＆DQ＆T steels. Transmission electron microscopy （TEM） and electron backscattering diffraction （EBSD） of the DQ steels showed smaller block width and higher density of dislocations. Inheritance of austenite deformation substructure by the martensite and differences in martensite block width were ruled out as major causes for the strength differences between DQ and RQ steels.     

Optimal operation of multi-storage tank multi-source system based on storage policy

A two-stage method is developed to solve a new class of multi-storage tank multi-source （MTMS） systems. In the first stage, the optimal storage policy of each tank is determined according to the electricity tariff, and the ground-level storage tank is modeled as a node. In the second stage, the genetic algorithm, combined with a repairing scheme, is applied to solve the pump scheduling problem. The objective of the pump scheduling problem is to ensure that the required volume is adequately provided by the pumps while minimizing the operation cost （energy cost and treatment cost）. The decision variables are the settings of the pumps and speed ratio of variable-speed pumps at time steps of the total operational time horizon. A mixed coding methodology is developed according to the characteristics of the decision variables. Daily operation cost savings of approximately 11% are obtained by application of the proposed method to a pressure zone of S. Y. water distribution system （WDS）, China.     

高强捆带钢发蓝工艺研究

WKD930（武钢930MPa捆带钢）的发蓝工艺实验及其产品的理化检验结果表明,在保证产品力学性能的前提下,该工艺在一定程度上能够改善发蓝层的质量,提高WKD930的耐蚀性能。