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131.
Typical cationic and anionic surfactants were chosen and their interactions were calculated by quantumchemical method. Interaction energies are -0.2378kJ·mol~(-1),-3.3394kJ·mol~(-1) and 0.1204kJ·mol~(-1) for the molec-ular pairs with fluocarbon and hydrocarbon chain: C_4H_(10)/C_5H_(12), C_4F_(10)/C_5H_(12), and C_4F_(10)/C_5F_(12), respectively.When hydrophilic group with cationic and anionicions is introduced, interaction energies are -287.40kJ·mol~(-1),-311.18kJ·mol~(-1) and -345.83kJ·mol~(-1). The results show that there is strong static interaction between cationicand anionic surfactants. It has been predicted that mixed monolayer may be formed and surface activity is en-hanced favorably, especially for mixtures of cationic and anionic surfactants with fluocarbon and hydrocarbonchains. The anionic surfactants, sodium octadecylbenzenesulfonate perfluopolyetherbenzenesulonate(ANF-Ⅰ)wassynthesized, mixture effects of ANF-Ⅰ with sodium octadecylbenzenesulfonate or dodecyldimethyl benzylammonium  相似文献   
132.
侯毓汾  李卓舒 《化工学报》1987,38(3):312-317
本文对苯骈噻吩酮衍生物甲川型分散染料不同的结构品种,进行了热熔固色率测定;研究了染料分子结构与染料在涤纶上的固色性能,染料的溶解度参数与固色率的关系.  相似文献   
133.
微孔无机膜反应器研究   总被引:6,自引:0,他引:6  
主要介绍了无机膜在化学反应中的应用--膜反应器研究,对膜反应器的特点、类型、应用、影响因素以及与其它反应器的比较进行了评述,并对其应用前景进行了展望。  相似文献   
134.
新型供水管材-AGR管(亚克力共聚PVC管),采用超微粒子丙烯酸树脂弹性体与PVC接枝共聚而成,在保持原有PVC刚性性能基础上,提高了低温冲击性能及卫生性能,可用于供水管、抗震管及其他饮料和化工流体的输送。  相似文献   
135.
本文研究了用碳酸钙作盐基度调整剂,从高岭土制聚羟基氯化铝的新方法.考查了酸浸液浓度及盐基度、反应温度和时间等因素对调整过程的影响。并制得了聚羟基氯化铝.  相似文献   
136.
李凭力  侯文贵  王世昌 《化工进展》2002,21(Z1):145-150
在自制的中空纤维膜器中研究了膜萃取过程的传质特性.研究表明,自制的带折流板的膜器可以提供较高的传质效率.增大水相流速可以提高传质速率,而改变有机相流速对传质没有影响.通过对实验数据的回归分析得出了折流膜器的壳间传质关联式.该研究对折流膜萃取器的开发和设计具有参考价值.  相似文献   
137.
The growing number of processing cores in a single CPU is demanding more parallelism from sequential programs. But in the past decades few work has succeeded in automatically exploiting enough parallelism, which casts a shadow over the many-core architecture and the automatic parallelization research. However, actually few work was tried to understand the nature, or amount, of the potentially available parallelism in programs. In this paper we will analyze at runtime the dynamic data dependencies among superblocks of sequential programs. We designed a meta re-arrange buffer to measure and exploit the available parallelism, with which the superblocks are dynamically analyzed, reordered and dispatched to run in parallel on an ideal many-core processor, while the data dependencies and program correctness are still maintained. In our experiments, we observed that with the superblock reordering, the potential speedup ranged from 1.08 to 89.60. The results showed that the potential parallelism of normal programs was still far from fully exploited by existing technologies. This observation makes the automatic parallelization a promising research direction for many-core architectures.  相似文献   
138.
Li Y  Hou MJ  Ma J  Tang ZH  Zhu HL  Ling WH 《Lipids》2005,40(5):455-462
In the present study we investigated the effects of dietary fats containing predominantly PUFA, monounsaturated FA (MUFA), or saturated FA (SFA) on lipid profile and liver cholesterol 7α-hydroxylase (CYP7α1) mRNA expression and bile acid production in C57BL/6J mice. The animals (n=75) were randomly divided into five groups and fed a basic chow diet (AIN-93G) (BC diet), a chow diet with 1g/100g of cholesterol (Chol diet), a chow diet with 1g/100g of cholesterol and 14g/100g of safflower oil (Chol+PUFA diet), a chow diet with 1g/100g of cholesterol and olive oil (Chol+MUFA diet), or a chow diet with 1g/100g of cholesterol and myristic acid (Chol+SFA diet) for 6 wk. The results showed that the Chol+SFA diet decreased CYP7α1 gene expression and bile acid pool size, resulting in increased blood and liver cholesterol levels. Addition of PUFA and MUFA to a 1% cholesterol diet increased the bile acid pool production or bile acid excretion and simultaneously decreased liver cholesterol accumulation despite decreased CYP7α1 mRNA expression. The results indicate that the decreased bile acid pool size induced by the SFA diet is related to inhibition of the liver CYP7α1 gene expression, but an increased bile acid pool size and improved cholesterol homeostasis are disassociated from the liver CYP7α1 gene expression.  相似文献   
139.
Poly(5‐bromoindole) (PBrI) films were synthesized electrochemically by direct oxidation of 5‐bromoindole in pure boron trifluoride diethyl etherate. The oxidation potential of 5‐bromoindole in this medium was measured to be only 0.97 V vs. saturated calomel electrode, which was lower than that determined in acetonitrile + 0.1 mol L?1 Bu4NBF4 (1.08 V). PBrI films obtained from this medium showed good electrochemical behavior and good thermal stability. Structural studies showed that the polymerization of 5‐bromoindole ring occurred at 2,3 position. As‐formed PBrI films were thoroughly soluble in strong polar solvent dimethylsulfoxide and partly soluble in tetrahydrofuran. Fluorescent spectral studies indicated that PBrI was a good blue‐light emitter. The excitation and emission spectra of PBrI showed a significant shift to longer wavelength compared with that of the monomer, consistent with the greater extent of electron delocalization. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 539–547, 2006  相似文献   
140.
以烧结板状刚玉、锆莫来石、天然鳞片状石墨为主原料 ,酚醛树脂为结合剂 ,Al、Si、B4C、Mn粉为添加剂 ,经 1 4 50℃埋炭烧成后 ,制成铝炭和铝锆炭系列试样 ,并对各试样的抗渣侵蚀性能进行了对比研究。结果表明 :在铝锆炭材料中 ,当Mn与Al、Si复合加入且Mn与C的质量比为 1∶4时 ,试样的抗侵蚀性和渗透性均较好 ;在铝炭材料中 ,当Mn与Al、Si、B4C复合加入且Mn与C的质量比为 1∶4时 ,试样的抗渗透性较好  相似文献   
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