铜基合金中溶质元素的Lnr0i的模型计算

采用自由体积理论和Ｍｉｅｄｅｍａ生成热模型，导出了液态合金中溶质元素的ｌｎｒｉ０的计算公式；计算了１２７３Ｋ下铜液中溶质元素的ｌｎｒｉ０。结果表明，计算值和实验值的正负号一致率为９０％，并基本处于同一数量级。     

Structural evolution of a sedimentologically homogeneous coal series as a function of carbon content by solid state 13C n.m.r.

The cross polarization technique combined with magic-angle spinning has been applied to obtain ¹³C n.m.r. spectra of a sedimentologically homogeneous series of peat, lignite and bituminous coal derived from higher plants. Despite some uncertainties on the quantitative aspects of the method, the structural information obtained was corelated with data from elemental analysis. Structural average parameters were also calculated by using the structural basic unit concept and relating it to the maturation stage of the organic matter.     

Influence of texture on optical and electrical properties of diamond films

The optical and electrical properties of variously textured diamond films have been investigated in this paper. SEM and Raman spectrum indicated that the films produced were of high quality with either (0 0 1) or (1 1 1) orientation. A four-layer model was used to fit the measured spectroscopic ellipsometry data. The results indicated that the properties of (0 0 1)-oriented diamond films were superior to those of (1 1 1)-oriented one. The refractive index and extinction coefficient of (0 0 1)-oriented diamond film in the infrared region of 2500-12500 nm was measured as 2.391 and of the order of 10⁻⁵, respectively and that for (1 1 1)-oriented one was 2.375 and of the order of 10⁻⁴, respectively. The dark current of the (0 0 1)-oriented diamond film was measured as 33.7 nA for an applied electric field of 100 kV cm⁻¹, its resistivity being about 2.33×10¹⁰ Ω cm. Current passing through the (0 0 1)-oriented diamond film during testing did not change significantly.     

超塑化剂与水泥相容性测定方法应用技术研究

通过对目前用于评价超塑化剂与水泥相容性的净浆流动度(GB/T8077-2000)法、旋转粘度计法以及Marsh筒法等几种测定方法对比性研究,论述了Marsh筒法显著的优越性,同时提出了完整的超塑化剂与水泥相容性概念,并从工程实践角度验证了其对生产的指导意义。     

激光蒸凝法工艺参数对Zn/ZnO纳米粒子性能的影响及临界粒子半径r*的研究

采用激光蒸凝法 ,以 1 50WCWCO2 激光器为光源 ,金属Zn为靶材 ,成功地制备出了Zn和ZnO纳米粒子。较详细地研究了实验参数对纳米粒子性能的影响 ,并应用经典成核理论对粒子的形成过程进行了研究。实验结果表明 ,制备工艺条件对形成的纳米粒子有一定的影响 ,反应压力和载气流量影响纳米粒子的形貌。不同的反应气氛制备的产物不同 ,在惰性气氛下产品纳米粒子是Zn和ZnO的混合物 ,在氧气气氛下 ,所得的纳米粒子是纯ZnO ;在氢气气氛中得到较纯的Zn纳米粒子。通过对临界粒子半径r 的回归分析 ,说明Zn纳米粒子的粒径主要由反应压力控制 ,而与载气流量关系不大     

张店油田注水井粘土稳定剂配方的室内筛选

张店油田属强水敏地层，注水开发的关键是防止储层发生粘土膨胀，对一系列粘土稳定剂进行粘土防膨和岩芯流动试验，筛选出适合张店油田注水井的最佳粘土稳定剂配方为2％JJA＋2％NH4Cl。用该配方处理后的岩芯，注张店注入水50PV后，渗透率保持率达94．74％。     

浅谈Schneider(C) Premium(R) PLC在水电厂控制中的应用

以莲花发电厂机组变压器强油风冷系统的PLC控制为例,浅谈Schneider(c) Premi-um(r)PLC在水电厂控制中的应用。     

路堤荷载下复合地基加固区压缩量的解析算法

在假设的位移模式下,考虑桩土相互作用,通过力学推导,得到了路堤荷载下复合地基桩侧摩阻力和加固区桩间土压缩量的解析表达式,并获得了桩土应力比的解析表达式。进行复合地基沉降计算时,可按本文建议的方法计算加固区桩间土的压缩量。     

纳米铜微粒作为润滑油添加剂的分散方法及其摩擦学性能研究

采用化学改性法与液流粉碎机械法对纳米铜微粒进行了表面改性和分散研究，采用高速离心机考察了表面改性后纳米铜微粒作为添加剂在CD15W／40柴油机油中的分散性及分散稳定性，采用TEM、XRD测试了表面改性纳米铜微粒的形貌及粒径大小，采用球一盘磨损试验机考察了表面改性纳米铜微粒作为CD15W／40全配方调配油添加剂的摩擦学性能，用SEM、EDS观察了磨损表面的形貌、线扫描、面分布及元素含量，分析了纳米铜微粒在摩擦过程中的减摩润滑机理。结果表明：甲基丙烯酸甲酯化学改性结合液流粉碎方法处理后纳米铜微粒的粒径进一步均匀、细化，平均粒径为24nm，并在CD15W／40油中分散性好，悬浮稳定时间长。当纳米铜微粒在CD15W／40油中添加量为0．05％时，具有最优的减摩抗磨性能，能使CD15W／40油抗磨性能提高1．57倍、减摩性能提高27．6％，这是因为纳米铜在摩擦表面的划痕和犁沟处沉积并形成边界润滑膜，从而降低了摩擦，改善了磨损。