Delamination Strength of WC-Co Thermal-Sprayed Coating Under Combined Stresses by Torsion-Tension Pin-Test Method

In this report, the delamination strength of WC-Co thermal-sprayed coatings under combined torsion and tension is evaluated using a newly developed method, which is called the torsion-tension pin-test. First, the effects of both the pin diameter and the coating thickness on the apparent delamination strength were investigated experimentally. Second, the stress distributions around the interface edge between the pin and the coating were numerically obtained by using the finite element analysis program “MARC.” It was confirmed that the fractured plane of the torsion pin coincides with the interfacial plane between the coating and the pin. The apparent delamination strength obtained experimentally decreased linearly with increasing pin diameter and increased with increasing coating thickness t, but it was stable at t of 400 μm or more. The shear delamination strength decreased with increasing tensile stress. Similar stress distributions were observed at the interface when delaminations occurred for rather thick coatings, independent of the pin diameter. The critical combination of the strength of shear stress fields (Ks) with that of tensile stress fields (Ka), i.e., the delamination criteria of the coating under combined shear and tensile loadings, was obtained for a WC-12Co thermal-sprayed coating. These combinations were found to be independent of pin diameter and coating thickness.     

埋藏条件下软弱夹层变形模量研究

在工程建设中,软弱夹层是影响岩体工程特性的重要因素,因软弱夹层揭露后易松弛,且松弛速度快,通常情况下很难得到初始条件变形模量参数。通过在玄武岩地区百余米深的平洞内进行的原位特大型变形试验,在预留软弱带上部的保护岩层以防软弱带松弛条件下,得到软弱夹层与上部不同厚度盖层的综合模量。利用弹性力学的原理求得软弱夹层在深埋原位状态下的变形模量,研究结果表明软弱带在深埋条件下具有较高的变形模量。     

类胡萝卜素肠道吸收与代谢的影响因素研究进展

类胡萝卜素是类异戊二烯单元组成的一类萜类色素,在维持眼部健康、提高免疫力等方面具有重要作用。人体不能合成这种色素,必须从膳食中摄取。人体摄入后,类胡萝卜素会经历复杂的消化吸收与代谢过程,并受到食物本身以及人体内环境等多种因素的影响。肠道是类胡萝卜素吸收、代谢最重要的场所。本文综述化合物结构、膳食因子、加工方式、包埋、转运蛋白、生物裂解酶等因素对类胡萝卜素在肠道吸收、代谢的影响,并探讨肠道菌群在其中发挥的作用,为类胡萝卜素体内的吸收与生物转化研究提供参考。     

白云鄂博铁矿企业文化建设初探

立足白云鄂博铁矿现实基础,依据包钢企业文化定位,阐述了应该辩证地看待企业文化,发扬国有企业重视思想政治工作的优势,努力建设具有矿山特色的企业文化.     

关于企业内部会计控制职能的探讨

建立和完善企业的内部会计控制制度,已经成为当今理论界和实务界最为关注的话题之一.研究内部会计控制,对于改善我国企业内部控制现状,保证会计信息质量,完善公司治理和信息披露制度,保护投资者的合法权益并保证资本市场的有效运行是十分必要的.     

废酸碱水处理的工艺研究

针对电厂化学车间阴阳离子交换器再生时废酸水量多于废碱水量的不平衡现象,及中和效果不达标的特点,通过分析废酸碱水不平衡产生的原因,对其产生过程进行控制,改进废水中和处理系统,增加有效中和装置,并在生产实践中总结并应用动态中和操作法,不仅使废水处理达到国家排放标准(pH=6～9),而且实现了回收再利用,取得了良好的效果.     

薄板连铸连轧过程控制和生产管理计算机系统

从薄板坯连铸连轧生产线中过程和生产管理计算机系统的应用角度,详细地介绍了管理计算机系统从订单到生产计划的整个过程,对过程控制计算机系统的模型建立过程和计算机控制系统构成及完成的主要控制功能进行了详细说明.     

Gateway Selection Protocol in Hybrid MANET Using DYMO Routing

In this paper, we propose a novel gateway (GW) selection protocol in hybrid Mobile Ad hoc Networks (MANETs). We focus on the situation that occurs when specialized, sensitive data is sent to the Internet from MANET nodes. These special data types are especially susceptible to security risks such as information leak and data falsification. Therefore, it is necessary for such special data to be forwarded by a secure/trusted GW which is controlled by a trusted network administrator. However, there should be multiple GWs deployed in a MANET, where the cost ineffectiveness makes it difficult for a network administrator to simultaneously manage every GW. Because of the risk of forwarding special data through an unmaintained GW, we propose a routing protocol which allows a source node to have sensitive data forwarded to the Internet through a trusted GW. To achieve this desirable performance, we improve upon one of the newest routing protocols, Dynamic MANET On-demand (DYMO), which works in consideration of application data. Through simulations, we evaluate our protocol in comparison with the conventional DYMO protocol. The results show that our protocol can make MANET source nodes choose GWs for specific data.     

住房公积金贷款的风险及防范对策

文章从微观的角度,运用理论分析的方法阐述了风险产生的原因,列举了造成住房公积金贷款风险的种种可能;结合包钢住房公积金贷款风险管理的实例,针对风险产生的原因提出了具体的风险防范措施。期望能对各住房公积金管理中心在个人住房贷款风险管理方面提供有益启示和借鉴。     

20CrMoA抽油杆用钢试制实践

文章主要介绍了20CrMoA抽油杆用圆钢试炼情况,采用转炉—精炼—小方坯连铸—连轧圆钢的工艺路线生产的产品,其各项性能及技术指标都达到设计要求。