扫描速度对硼铸铁气缸套表面钨极氩弧硬化效果的影响

研究了钨极氩弧扫描速度对硼铸铁表面硬化效果的影响规律。结果表明：扫描速度增加,硬化层宽度、深度减小,而硬度提高,裂纹率增大；硬化层硬度沿层深的分布是从表及里由高而低,在过渡区下降缓慢；沿层宽的分布是层中心最高,向两侧逐渐降低,直至硼铸铁基体达到最低值；在保证不出现裂纹的条件下,硬化层表面的最高硬度值可达61．4HRC,硬化层最高显微硬度值可达1156．4HV0．1；硼铸铁材料采用氩弧热源淬火时,淬硬层与基体之间过渡区明显,硬化区组织为莱氏体,过渡区为马氏体、残余奥氏体和少量石墨。     

脱除重油中有害金属杂质新技术

用化学药剂在一定条件下进行反应后用水萃取，并用 电脱水的方法脱除金属.研究了注药剂量、反应温度和反应时间等因素对脱除率的影响.     

K38G合金及其溅射微晶层的高温氧化

研究了K38G铸造镍基高温合金及其用平面磁控离广溅射工艺制备的微晶涂层在800-1000℃500小时内的抗高温氧化性。结果表明,微晶化极大改善合金的抗氧化能力,并改变合金表面生成的氧化物类型,由Cr_2O_3变为α-Al_2O_3。还讨论了铸态K38G合金及溅射微晶层的氧化机理。     

LOCALIZED CORROSION OF MICROCRYSTALS OF 1Crl8Ni9Ti STAINLESS STEEL

The resistances against localized corrosion of 1Cr18Ni9Ti microcrystals with normal grainsize and bcc structure obtained hy magnetron sputtering have been compared.The two kindsof microcrystals with (110) and (211) textures respectively were obtained under differentsputtering conditions.Both microcrystals were found to have better resistance against local-ized corrosion than the crystal with normal grain.The microcrystal with (110) preferredorientation has larger resistance to localized corrosion than that with (211) preferredorientation.     

Electron beam welding of Re and BT5-1 titanium alloy

Based on the binary alloy phase diagram of Re-Ti, the weldability of Re and BT5-1 titanium alloy was analyzed. Using two methods of direct electron beam welding （EBW-D） and intergradafion electron beam welding （EBW-I）, Re and BT5-1 was welded. Experimental results show that the joint figuration of EBW-D between Re and BT5-1 is not fine, and the joint is inclined to brittleness rupture. The joint figuration of EBW-I between Re and BT5-1 is fine. No cracking and other disfigures occur in the intergradation joint. The element distribution of Re, Me, and Ti in the weld metal is progressional diversification.     

Advances in the research of nitrogen containing stainless steels

The current status of nitrogen containing stainless steels at home and aboard has been introduced. The function and existing forms of nitrogen in the stainless steels, influence of nitrogen on mechanical properties and anti-corrosion properties as well as the application of nitrogen containing cast stainless steels were discussed in this paper. It is clear that nitrogen will be a potential and important alloying element in stainless steels. And Argon Oxygen Decarbonization (AOD) refining can provide an advanced manufacture process for nitrogen containing stainless steels with ultra-low- carbon and high cleanliness.     

STUDIES ON FLOODING POINT AND HOLD-UP IN A SOLVENT EXTRACTION COLUMN WITH RECIPROCATING SIEVE PLATES

The flooding point and hold-up of the dispersed phase in an extraction column with reciprocating-sieve plates of 32 mm inside diameter and 1960 mm effective column height have been investigated under thefollowing conditions:Percent perforation of the plates 40%,53.5% and 63.7%,diameters of perforatedholes 7.8,9.0 and 9.8 mm,and distances between plates 20 and 40 mm respectively.Experiments werecarried out with three different liquid-liquid systems covering a rather wide range of physical properties.The relative velocity of the two phases passing through the perforations of the plates is consideredin the present work to be related to the work done by the oscillating plates in the column on unit massof liquid in unit time.Therefore the flooding velocity and hold-up in extraction column with reci-procating sieve plates should be related to A~2F~3 instead of AF as reported before.Equations weredeveloped to correlate the experimental data of flooding point and hold-up respectively.     

混杂系统的一致输入输出对状态稳定性

混杂系统的输入输出对状态稳定性是混杂控制系统领域极富挑战性的课题之一. 为了观测混杂系统的状态,本文提出了一类混杂系统的一致输入输出对状态稳定的充分条件,分析了混杂系统的一致输入输出对状态稳定性、光滑Lyapunov函数存在性和状态模估计器存在性三者之间的关系. 借助状态模估计器将混杂系统化为受扰动系统,获得了受扰动系统一致输入输出对状态稳定性的结果,并进一步证明了混杂系统的一致输入输出对状态稳定性.     

1，4-环己烷二甲酸

介绍了1,4-环己烷二甲酸的物化性质、性能特点及应用,并综述了其专利制备技术的研究进展。     

基于Hg~(2+)诱导DNA双链形成的汞离子检测试纸条研制

Hg2+能特异性地与2个胸腺嘧啶碱基(T)共价结合,介导T-T错配形成稳定的T-Hg2+-T结构。基于DNA修饰的纳米金探针研制了一种可检测水溶液中Hg2+浓度的层析试纸条。试纸条包含1条控制线和2条测试线,检测结果在5 min内可见,裸眼可见检测灵敏度为100 nmol/L。金标条阅读仪分析结果在10 nmol/L~10μmol/L范围内具有良好的线性关系,且对常见二价重金属离子Cu2+,Ni2+,Mg2+,Zn2+,Pb2+具有很好的选择性。该试纸条灵敏特异、快捷简单、操作方便、成本低廉,在环境监测和食品安全的现场快速检测中具有很好的应用前景。