Asymmetric epoxidation of <Emphasis Type="Italic">α</Emphasis>,<Emphasis Type="Italic">β</Emphasis>-unsaturated ketones using <Emphasis Type="Italic">α</Emphasis>,<Emphasis Type="Italic">α</Emphasis>-diarylprolinols as catalysts

Asymmetric epoxidation of α,β-unsaturated ketones has been extensively studied and several important procedures have been developed in the last decade. This review addresses the most significant advances in asymmetric epoxidation of α,β-unsaturated ketones using proline-derived α,α-diarylprolinols as catalysts. Special attention has been paid to the enantioselective epoxidation of chalcones, α,β-unsaturated trifluoromethyl, trichloromethyl ketones and β,γ-unsaturated α-keto esters based on the reseach of our group.     

染料在共混丙纶中的吸附和扩散

通过采用添加少量烯烃类高聚物的方法,制得可染共混丙纶,对其染色速度和染色平衡进行了研究。研究结果表明,染色速度与染色温度、染料结构有很大的关系,染色的等温吸附线属于Nernst型。     

烃类裂解烯烃产率分布模型

采用经验法，以芳烃指数、裂解温度、停留时间为参数，建立烃类裂解烯烃产率分布模型。该模型具有较高精度，可用于根据已定的原料特性和所要求的产品结构确定合适的操作条件，或在原料改变后预测产品分布的变化。     

Mesoporous zeolite SBA-15 supported nickel diimine catalysts for ethylene polymerization

The novel mesoporous zeolite SBA-15 is successfully used as the support to immobilize late-transition metal nickel diimine catalyst, both in physical and chemical methods, EA, ICP, FT-IR and XRD are applied to characterizing these supported catalysts. The results of ethylene polymerization reveal that these supported catalysts have high catalytic activity as their homogenous counterpart does,moreover, polyethylene with a fibrous morphology is produced due to the channel effect of support, and both the molecular weight and molecular weight distributions of polymers are increased greatly.     

H2O2-有机酸降低汽油中烯烃含量研究

用H2O2(w=30%)对含烯烃的模拟油品进行氧化,探讨了各种催化剂对氧化反应的影响。结果表明,酸碱催化剂都可促进H2O2氧化反应的进行,对降低油品中烯烃效果,有机酸条件明显好于碱性和中性条件,甲酸的催化效果优于乙酸。在H2O2 甲酸氧化降烯烃的过程中,当3种样品的体积比即V(模拟油品):V(H2O2)∶V(甲酸)=4∶1∶1,反应温度45℃,反应时间1h时,模拟体系中烯烃降低率为35.8%,流化催化裂化汽油中烯烃降低率达22.1%。     

Efficient Hydration of Olefins Catalyzed by Wool-Supported Palladium Complex

1 Introduction The hydration of olefins is one of the most important processes for the production of alcohols~([1]). Both transition metal complexes~([2]) and enzymes~([3]) have been reported to catalyze the hydration of alkenes, but their catalysts are usually either unstable or difficult to prepare, expensive and sometimes can not be easily recovered.1IntroductionThe hydration of olefinsis one of the most i mportant processes for the production of alcohols[1].Bothtransitionmetal complexes[2…     

室温离子液体对催化裂化汽油的降烯烃性能研究

研究了[BmIm]Cl—AlCl3室温离子液体对催化裂化汽油的降烯烃性能。结果表明，在温度为40℃，反应时间为20min和剂油比为1：5的条件下，催化裂化汽油烯烃含量下降14．70％，辛烷值基本不变，离子液体可重复使用。离子液体的超强酸性能对汽油中的低碳烯烃与异构烷烃的烷基化、与芳烃的Fridel—Crafts烷基化以及烯烃自身的二聚反应起到催化作用，从而达到降烯烃的目的。     

Separation of C6-Olefin Isomers in Reactive Extractants

Chemical complexation, in which certain metal ions （especially Ag^＋ and Cu^＋） reversibly and selectively complex olefin isomers, was used to separate 1-hexene from a mixture of internal hexenes as an attractive alternative to traditional distillation. Several potential reactive extractants were investigated for their selectivity of both 1-hexene to 2-hexene and 1-hexene to 3-hexene. With 3 mol/L AgNO3-N-methyl-pyrrolidone （NMP） solution as extractant, the selectivity of 1-hexene to 3-hexane was increased to about 2.0 and the selectivity of 1-hexene to 2-hexene reached 1.5. Both the raffinate phase and the extracted phase were analyzed using a gas chromatograph equipped with a flame ionization detector and a 50-m capillary column. The experimental results show that the silver nitrate NMP solution has the better selectivity than other reactive extractions.     

A potential approach to replace sulfurized olefins with borate ester containing xanthate group in lubricating oil

To develop a potential substitute for sulfurized olefins, a borate ester derivative containing xanthate group （titled BXT） was synthesized and characterized. Meanwhile, its tribological properties in rape-seed oil were evaluated using four-ball tribometer. The results indicate that BXT shows excellent tri- bological capacity such as load-carrying, friction-reducing and antiwear property. Moreover, the synthesized compound has no noticeable odor, shows little corrosion to copper, and exhibits better thermal stability compared with sulfurized olefins. In order to study the action mechanism of BXT in friction process, analysis of the worn surface was carried out using a three-dimensional non-contact surface profilometer and XPS analyzer.