The effect of LaF3 nanocluster modified with succinimide on the lubricating performance of liquid paraffin for steel-on-steel system

LaF₃ nanocluster modified with succinimide was prepared. The effect of the modified LaF₃ nanocluster on the lubricating performance of liquid paraffin for steel-on-steel sliding system was investigated on a four-ball machine. The morphology of LaF₃ and its lubricating mechanisms as additive in liquid paraffin were studied by means of transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). It was found that LaF₃ nanocluster modified with succinimide as an additive in liquid paraffin increased the load-carrying capacity and had good antiwear and friction-reduction behaviour. The XPS analysis of the worn steel surfaces indicated that a boundary lubricating film consisting of physically adsorbing film (succinimide) and tribochemically reacting film (lanthanum oxide and ferrous fluoride) was generated during the friction process. This contributed to improving the lubricating performance of liquid paraffin.     

小截留分子量共混超滤膜的研究（I）—PVDF与PVAc的混溶性

以聚偏氟乙烯（PVDF）和聚醋酸乙烯酯（PVAc)共混,采用相转化法制备亲水性小截留分了量共混超滤, 本工作的第于阶段,用烯溶液粘度法研究了PVDF和PVAc的混溶性,结果表明这两种聚合物可以任意的共混比混溶。     

小截留分子量共混超滤膜的研究(Ⅱ)——PVDF与PVAc共混前后超滤膜性能的比较

以聚偏氟乙烯 (PVDF)和聚醋酸乙烯酯 (PVAc)共混 ,采用相转化法制备亲水性小截留分子量共混超滤膜 .本文对PVDF和PVAc共混前后超滤膜性能进行了比较 ,结果表明 ,在相同截留率的前提下共混超滤膜的水通量得到提高且在经济性上也有较大的改善     

一种新的微型激光器材料--稀土掺杂玻璃

制得了具有双包层结构的掺Nd^3 和Yb^3 单模磷酸盐玻璃光纤,用中心波长为800nm的半导体激光器件钕光纤的光泵源,在室温下获得了波长为1．053um,输出功率为8．36mW的连续激光输出,用930nm的钛宝石激光泵浦掺镱光纤,也获得了1．067um的激光,研究了Nd^3 ,Yb^3 ,Er^3 离子掺杂四磷酸盐玻璃和氟化物玻璃的发光性能与浓度的关系,以及Yb^3 /Er^3 双掺杂玻璃的发光性能,得到了掺钕四磷酸盐玻璃,Yb^3 /Er^3 双掺四磷酸盐玻璃和掺氟铝酸盐玻璃等几种在微片激光器有应用前景的材料。     

Mechanical properties and ionic conductivity of gel polymer electrolyte based on poly(vinylidene‐fluoride‐co‐hexafluoropropylene)

The main thermodynamic parameters were evaluated for the dextran/methoxy ethylene glycol (MEG) system by viscosity measurements at 25, 30, 35, 40, and 45°C. The long-range and short-range interaction parameters were determined by extrapolation methods, i.e, Kurata-Stockmayer-Fixman, Berry, and Inagaki-Suzuki-Kurata equations. Calculated values, as well as the unperturbed root-mean-square end-to-end distance and hydrodynamic expansion factor, were interpreted mainly on the basis of hydrogen-bond formation between polymer segments and dextran/MEG molecules in solution. The thermodynamic interaction parameter was also evaluated for the same system. The theta temperatures were obtained from the temperature dependence of the interaction parameter, dependence of (1/2-χ) and the second virial coefficient in the temperature interval of 25 and 45°C for the system and quite a good accordance was indicated with the calculated values evaluated via extrapolation and interpolation methods. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 948–953, 2001     

BaTiO3基陶瓷PTC效应理论模型研究

综述了近年来提出的各种PTCR效应模型解释。但是从各种与传统模型相背的异常试验现象来看,建立完善的PTCR效应解释模型还需要做大量的工作。     

聚偏氟乙烯/碳黑导电复合材料的电学性能

溶剂法制得的 PVDF/CB复合材料 ,表现出明显的 PTC和 NTC特性 ,被动退火和辐射交联可部分消除材料内应力和缺陷 ,使材料的电性能趋于稳定 ;充分交联可消除材料的 NTC效应     

铌酸锶钡铁电薄膜的微结构与薄膜厚度的关系

叙述了使用溶胶—凝胶法在 Si( 0 0 1 )基片上制备不同厚度的铁电铌酸锶钡薄膜的过程 ,使用 X射线衍射 ,扫描电子显微镜 ,拉曼散射光谱等方法研究薄膜的微结构与薄膜厚度之间的关系 ,薄膜的厚度一直能够达到 5 μm。实验发现 ,随着厚度的增加 ,SBN60薄膜在 ( 0 0 1 )方向的优先取向性越来越好。在逐层生长的过程中 ,处于底层的膜层能够起到缓冲层的作用 ,以逐渐改善薄膜与基片之间的晶格失配 ,从而使得晶体的结晶取向性越来越好     

硫酸钡纳米粉体的液相合成方法

本文着重介绍硫酸钡纳米粉体的液相合成方法。以BaS和NaSO4为原料,以旋转填料床为强制混合器进行液相沉淀反应。并简要阐述其中的成核机理,系统考察了溶液的过饱和程度、转速、分散剂等因素对平均粒径的影响,最终确立了最优工艺条件。