微乳液法制备纳米二氧化硅及表征

制备Triton X—10/正辛醇/环己烷/水(或氨水)油包水(W/O)型微乳液,讨论了微乳液相关性质与含水量的关系;以正硅酸乙酯(TEOS)为硅源,在制备的微乳液中受控水解制得纳米SiO2粒子,并用FT—IR、TEM、比表面测定进行表征;结果显示含水量和硅源浓度与粒子尺寸相关,TEM照片显示粒径40~80 nm。     

Interfacial Peeling Moments and Shear Forces at Free Edges of Multilayers Subjected to Thermal Stresses

Stresses normal to interfaces, i.e., interfacial peeling stresses and interfacial shear stresses, exist locally at edges of multilayers because of both the thermal mismatch between layers and the free-edge effect. These peeling and shear stresses can result in modes I and II edge delamination, respectively. However, because of the complexity of the problem, exact closed-form solutions for these stresses are very difficult if not impossible to derive even for bilayered systems. Hence, instead of the detailed stress field at edges, both the interfacial peeling moment resulting from the localized peeling stresses and the interfacial shear force resulting from the localized shear stresses are analyzed here. Exact closed-form solutions for the peeling moment and the shear force at each interface in elastic multilayered systems are derived. To illustrate the application of present closed-form solutions, specific results are calculated for five-layered thermal barrier coating systems, and a finite-element analysis is also performed to confirm the analytical results.     

A rheological model for iron oxide suspensions

We have examined the rheological properties of a Co-adsorbed γ-Fe₂O₃ magnetic suspension with polyurethane (PU) as a binder and methyl ethyl ketone (MEK) or cyclohexanone (CH) as a solvent. A Haake RV20 viscometer was used to measure the suspension viscosity and the vane method was adopted to determine the fluid yield stress. A rheological model which can be viewed as a combination of the Casson model and the Bingham model is proposed to describe the suspension viscosity. The effects of temperature, particle content, and binder concentration are included in the model.     

多杀菌素的高效液相色谱法测定

采用高效液相色谱法对Saccharpolyspora spinasa发酵液中多杀菌素含量进行测定。本方法的相对标准偏差为0．11％。变异系数为0．15%．线性相关系数为0．99916．平均回收率为96.94％。     

凹凸棒石改性方法及其应用现状

介绍了我国凹凸棒石的矿产资源及改性技术的发展状况,叙述了凹凸棒石的各种改性方法,提出了微波改性方法的可行性.概括了国内外的应用和发展状况.     

C5石油树脂的研究及应用

阐述了C5石油树脂工艺,并综述了国内外近年来在催化剂性能的改进、降低三废问题以及对C5石油树脂的改性等方面的研究进展。介绍了C5石油树脂在路标漆、涂料、油墨、胶黏剂、橡胶助剂等应用方面的发展状况,并对我国C5石油树脂生产规模化、改性C5石油树脂品种化、系列化的发展提出了建议。     

氧化气氛下铜红花釉的研制

通过在基础釉中引入SiC及复合还原剂，成功地试制出氧化气氛下1130－1160℃烧成，适合各类艺术瓷装饰的低温慢烧铜红花釉配方；实验研究了复合还原剂影响结果，并且讨论了分析了PbO,B2O3等添加剂的作用机理，确定了它们的最佳加入量。     

An evaluation of commercial nickel catalysts during hydrogenation of soybean oil

The activities of several commercial nickel catalysts were determined by measuring their activation energies. Among these catalysts, G95E, Resan 22, Nysosel 222 and 325, all with low activation energy, were more active than DM3 and G95H, which had higher activation energy. However, the less active catalysts increased the linoleate selectivity of soybean oil during hydrogenation. The yields of bothtrans isomers and winterized oil were higher for the more selectively hydrogenated oil catalyzed by the less active catalysts. In the sensory evaluation, the fractionated solid fat that contained moretrans isomers was lower in flavor scores than the fractionated liquid oil after hydrogenation and winterization of soybean oil.     

厌氧发酵处理味精废水中氯离子的影响

在3L 的CSTR 型厌氧反应器中研究了味精废水厌氧处理中氯离子毒性的反应。试验证明,已中毒的厌氧过程只要Cl~-浓度降至抑制限以下,厌氧过程就可在15～20d 内恢复,在恢复期间加入新污泥有利于恢复过程。保持足够大的SRT 和污泥浓度对于处理含有毒物的废水很有效。对本研究,SRT 得大于20d,污泥浓度在15～24g/L 左右就可达到较好的处理效率。Cl~-的抑制浓度对污泥浓度分别为24.28g/L,15.18g/L 和6.07g/L 时,Cl~-的抑制浓度分别是7750mg/L,7250mg/L和6300mg/L。此外,本文提出以I=S_(Cl)/X_v~n作为判断Cl~-抑制的指标。当COD 去除率大于80%时,n=0.1519。因此,要使过程的COD 去除率分别大于80%,85%和90%时,I 就得分别小于4.7,4.1和3.6。并且污泥浓度必须大于6.07g/L。     

大潮差河口闸下水流的流动特性分析

福建数座河口水闸发生剧烈淘刷,闸上游和下游的最大冲刷深度达到闸室高度的0.5~1.2倍,且屡修屡毁。有的水闸经多次除险加固后,不得不再花巨资重建。通过数学模型和物理模型揭示了河口水闸下游水位因受东海大潮差海潮影响发生剧烈波动时的变化规律,发现了水闸泄流过程中的间歇性淹没及非常工况甚至出现逆流的独特流动现象,给出了典型日孔流及堰流泄流能力动态变化过程线,分析了消能工变化对闸址水流结构的显著影响,并对水闸水毁修复前后闸下冲刷进行了预测。结果表明:水闸修复前闸下涨急最高水位4.53 m,修复后下降0.67 m,水闸修复后逆流现象减弱。修复后首次水跃位置往上游移动了35 m,平均水跃高度下降47.46%,闸后及二级池末端最大流速2.27 m/s和0.08 m/s,较修复前分别下降了40.58%和96.48%。常遇泄流条件下,水闸的淹没度和泄流能力呈现不断变化的动态过程。当西溪水闸62#先启孔全开,上游保持正常高水位3.2 m,下游为最低潮位-0.72 m时,修复后最大冲刷深度减少64.48%,消能防冲效果十分明显。研究成果对河口水闸安全运行具有一定的参考价值。