A first-principles investigation on mechanical and metallic properties of titanium carbides under pressure

The titanium carbides are potential candidates to achieve both high hardness and refractory property. We carried out a structural search for titanium carbides at three pressures of 0 GPa, 30 GPa and 50 GPa. A phase diagram of the Ti-C system at 0 K was obtained by elucidating formation enthalpies as a function of compositions, and their mechanical and metallic properties of titanium carbides were investigated systematically. We also discussed the relation of titanium concentration to the both mechanical and metallic properties of titanium carbides. It has been found that the average valence electron density and tractility improved at higher concentrations of titanium, while the degree of covalent bonding directionality decreased. To this effect, the hardness of titanium carbide decreases as the content of titanium increases. Our results indicated that the titanium content significantly affected the metallic properties of the Ti-C system.     

低水分抗热震高铝可塑料在加热炉上的应用

用矾土作为主原料,选择适当结合剂和添加剂,引入微粉技术,采用真空炼泥等工艺手段,研制成低水分抗热震高铝可塑料。该制品用作热媒加热炉衬里,显示出良好的耐高温和耐热冲击性能。     

深圳市大型商场空气品质的测试与分析

本文根据对位于深圳市不同片区的五家大型商场进行室内空气品质现场检测所得的数据,分析了这些商场的室内空气品质状况,各商场不同楼层、不同售货区的空气品质参数分布规律,以及周末、平日、不同时段室内空气品质参数的变化规律,并结合现场实际情况对其原因进行了分析。     

CL－1型缓蚀剂的研制

为了阻缓高含水原油对集输管线的腐蚀，研制了ＣＬ－１型输油管线缓蚀剂。这种缓蚀剂是以两种咪唑啉衍生物与联氨为主要成分的复配药剂，运用于油水共在体系．本文介绍了该剂的室内性能评价和现场试验结果。     

防垢剂BZF－2的研制与应用

桩西油田产出原油综合含水已达６０％－７０％，原用防垢剂ＨＥＤＰ已失去有效抑制集输站结垢的性能。本工作针对结垢最严重的桩５２站的应用，研制了以有机膦化合物和聚氧乙烯醚为主成份的防垢剂ＢＺＦ－２，在室内考察了不同条件下的防垢率、腐蚀性、配伍性等性能，在桩５２站进行了为期４个月的现场试验，加量为１０．３ｍｌ／ｌ、防垢率≥９８．０％，加药设备管线的腐蚀率大大降低。     

丙烯腈－苯乙烯共聚物水解磺化产物对泥浆的稳定作用

在实验室条件下对用丙烯腈－苯乙烯共聚物在硫酸存在下的水解磺化产物（ＨＳＡＳ）处理的泥浆性能进行了评定。ＨＳＡＳ处理的泥浆有较小的滤失性，较好的耐盐和抗高温性。     

衍射法细丝直径的精密测量

分析了激光衍射法测量细丝直径技术中影响精度的几个主要因素，研究了一种微弱衍射条纹的精密处理及识别技术，有效地提高了测量精度，实测结果表明，文中讨论的技术能在１０￣５０μｍ的范围内实现正负０．１μｍ的重复精度，分辨力优于０．０１μｍ。     

锰铜基高阻尼合金中锌量的测定──硫氰酸盐萃取分离络合滴定法

基于甲基异丁基甲酮于稀盐酸介质中定量地萃取Ｚｎ￣（２＋）与ＣＮＳ￣－形成的络阴离子。从而达到与共存的锰、镍、铝、铬的完全分离。在有氟化物、硫脲存在时Ｆｅ￣（３＋）、Ｃｎ￣（２＋）和Ａｇ￣＋也不被萃取。有机相中的锌于ＰＨ５．５“六胺”缓冲介质中返萃取回水相，用ＥＤＴＡ滴定。在文中给定的条件下锌的一次被萃取率可达９９％以上，成功地解决了锰铜基高阻尼合金中共存离子对锌量测定的干扰问题。     

顶封封隔管柱的研制与应用

中原油田近年来注水压力不断升高，井况恶化严重，为此开发了顶封封隔管柱，主要阐述了管柱工况受力特点、结构、工作原理及现场使用效果。经现场较大面积的应用证明，各项性能、技术指标达到了现场要求。     

Comparison of inward and outward grown Pt modified aluminide diffusion coatings on a Ni based single crystal superalloy

Two commercial Pt modified aluminide coatings (RT22 and MDC150L) on the same single crystal Ni-based superalloy (CMSX-4) were studied by: scanning electron microscopy; transmission electron microscopy; energy dispersive X-ray spectrometry; and gravimetry. The RT22 coating is an inward grown coating (high activity), while MDC150L is produced by outward growth (low activity). Samples were oxidised in still laboratory air at 1050 °C for various times up to 2000 h. It was found that the outward grown coating produced a slower growing oxide that was more spallation resistant. Several possible reasons for this were identified including: coating purity; coating surface topography; and ductile to brittle transition temperature. The microstructural differences between the two coatings in the as-coated condition were investigated and the development of their microstructure during heat treatment was described. A model for coating growth during heat treatment was proposed.