Effect of carbide additions on grain growth in TiC−Ni cermets

The growth of carbide particles in TiC-XC-2 vol.% Ni and TiC-XC-30 vol.% Ni alloys, where X=Zr, Cr, W, Ta and Mo, was fitted to an equation of the form d³-d_o ³=Kt. The grain growth behavior during liquid phase sintering at 1673K decreased markedly with the addition of Mo₂C or WC, changed little for TaC, and increased with the addition of ZrC or Cr₃C₂. The grain contiguity decreased with increasing Ni content in the TiC−Mo₂C−Ni alloy and was greater in the alloys with smaller growth rate constant. Consequently, the effect of carbide addition on the grain growth of 2 vol.% Ni alloys was found to be similar to that of 30 vol.% Ni alloys. The grain growth mechanism could be explained by the effect of contiguous carbide grain boundaries in restricting the overall grain growth, as well as the area of the solid/liquid interfaces in the alloy by the usual solution/reprecipitation model.     

基于过程能力指数的刀具寿命研究

利用Glejser检验方法拟舍出刀具磨损过程残差模型，在此基础上，计算换刀时刻的过程能力指数，并且根据企业所要求的最低过程能力指数，计算刀具的质量寿命，提出将刀具的切削寿命和质量寿命结合起来进行换刀决策的方法。     

Photovoltaic collectors efficiency according to their integration in buildings

A model for building integrated photovoltaic systems has been developed and implemented in a dynamic simulation tool. This tool takes into account the thermal interactions between the PV collector and the building. The influence of the type of integration upon the PV collector efficiency has been evaluated and hybrid PV/air collectors have been studied. An overall efficiency is defined, including the production of electricity and heat. A case study has been performed on two different typical buildings. In the case of a multi-crystalline silicon PV collector integrated on the roof of a single family house located in Paris, the efficiency of unventilated PV modules fixed on the roof is 14%. If the PV collector is used to preheat the ventilation air, the efficiency reaches 20%. A proper building integration also improves the environmental balance of PV technologies over their life cycle.     

机械锁定式地层测试技术研究与应用

机械锁定式测试技术操作简单，测试一次成功率高，资料录取准确全面，且测试结束后可直接进行封堵作业；解封时，机械锁紧产生一个向上的震击力，有利于解封，没有换位机构的测试阀在关井期间使管柱处于自由拉伸状态，有利于保护油管。在N阀上部管柱中加1-2根伸缩接头，便可用于海洋井测试。     

The optimal diamond wheels for grinding diamond tools

Grinding is the most suitable process for manufacturing good quality diamond tools. In this paper, diamond wheels have been studied. From the grinding of polycrystalline diamond (PCD) insets, the effects of certain factors such as the bonding material, the grit size and structure of a diamond wheel have been investigated. It is concluded that vitrified bond diamond wheels are the most suitable for grinding PCDs and the recommended grit size is mesh number 1000, which can get a good surface quality within an appropriate time. The wheel structure is another important factor. Rougher wheels (mesh #800, #1000) with the softer grade scale P yield a higher material removal rate (MRR) than scale Q. However, a finer wheel (mesh #1200) needs a tougher structure to promote its grinding ability and to have a higher MRR.     

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四川目前生产的天然气中含硫天然气占７１％，而含硫天然气对高强度钻杆会产生硫化物应力腐蚀玻裂，因此，在含硫气井进行钻杆测试时，应重视钻杆的安全问题。文章探讨了高强度钻杆硫化物应力腐蚀玻裂的机理和影响钻杆脆断时间的各种因素，并提出在一定的条件下，高强度钻杆在含硫气并中进行测试是安全的。采用向钻杆内加缓蚀剂或内涂层钻杆，防硫油管测试，钻杆测试更加安全。建议继续开展高强度钻杆硫化物应力腐蚀玻裂时间的试验研究，以确定合理的钻杆测试安全时间。     

注入剖面五参数组合测井仪的改进

文章介绍了注入剖面五参数组合测井仪及对该仪器的改进与完善，特别是对流量计的结构进行了改进。流量计下端采用水阻尼和机械弹簧两种保护措施，有效地保护了涡轮；过芯加重改成通用加重下挂到涡轮流量计上，有效地减少了涡轮粘污，提高了组合测井仪的测井成功率。改进后测井成功率从60％提高到90％。同时。对数据处理与传输电路也进行了改进，新开发研制了PPM码数据传输体系，使组合仪耐温指标提高到175℃。     

山特维克可乐满公司切削刀具涂层技术的发展

介绍了山特维克可乐满公司切削刀具涂层技术的发展，并对该公司自1979年以来硬质合金涂层产品的发展情况进行了总结。     

C/C + +源代码风格检测工具的实现

文中给出了评价C／C 源代码风格的规则分类和检查工具的总体结构，阐述了代码检查工具的核心技术——扩展词法分析和扩展语法分析，给出了代码检测工具的应用实例。     

Minimizing the number of tool switches on a flexible machine

This article analyzes a tool switching problem arising in certain flexible manufacturing environments. A batch of jobs have to be successively processed on a single flexible machine. Each job requires a subset of tools, which have to be placed in the tool magazine of the machine before the job can be processed. The tool magazine has a limited capacity, and, in general, the number of tools needed to produce all the jobs exceeds this capacity. Hence, it is sometimes necessary to change tools between two jobs in a sequence. The problem is then to determine a job sequence and an associated sequence of loadings for the tool magazine, such that the total number of tool switches is minimized. This problem has been previously considered by several authors; it is here revisited, both from a theoretical and from a computational viewpoint. Basic results concerning the computational complexity of the problem are established. Several heuristics are proposed for its solution, and their performance is computationally assessed.