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The research developments in synthesis and application of silicotungstate with Keggin-type structure and its derivants used as catalysts in epoxidations of alkenes were reviewed.

综述了近十年来新型 Keggin结构硅钨酸盐及其一系列衍生物催化剂的合成及其在选择氧化反应中应用的研究进展。

A series of SiW_(12)/AC catalysts with different silicotungstic acid loadings supported on acti- vated carbon which was treated with 10% HNO_3 solution were prepared by an impregnation method and the catalytic performance of SiW_(12)/AC for the synthesis of trioxane were investigated.

以10%硝酸溶液处理过的活性炭为载体，采用不同质量分数的硅钨酸SiW_(12溶液为浸渍液，制备了不同负载量的SiW_(12)/AC催化剂，考察了催化剂在合成三聚甲醛中的催化性能，并用XRD、FT-IR、NH_3- TPD、BET、TG-DSC等手段对SiW_(12)/AC催化剂晶粒大小、催化剂表面的酸量及酸强度、比表面积及热稳定性等微观特性进行了表征。

Phenylethyl cinnamate was synthesized from cinnamic acid with β-phenylethyl alcohol using ultra stable Y zeolite supported silicotungstic acid as catalysts without solvent under microwave irradiation.

在微波辐射下，以超稳Y沸石负载硅钨酸为催化剂，不使用溶剂，合成了肉桂酸β-苯乙酯。

Based on the shortcomings of the COD determination method revised in National Standard, some improvement measures of the standard method, including improvement of slaking phrases, research of substitution catalysts and elimination of chlorine ion disturbance, are compared and discussed. Afterwards, some common substitution COD determination methods, such as correlation coefficient analysis method, electrochemistry analysis method, spectrophotometric analysis method and flow inject analysis method, are introduced.

在论述了国标中COD标准方法不足之处的基础上，本文就标准方法的众多改进措施分类进行了比较与探讨，包括消解方法的改进、替代催化剂的研究以及氯离子干扰的消除，然后介绍了相关系数法、电化学法、分光光度法和流动注射法等COD测定替代技术。

The results were discussed on the basis of steric and electronic effects of the substituents and the stability of the catalytic active sites. New ideas in designing catalysts were presented.

以取代基的立体效应和电子效应的影响及催化活性中心的稳定性为基础对上述结果进行了详细讨论，并根据实验结果提出了设计催化剂的新思路。

LY series desulfurizers are synthesized by sterically hindered fatty amine, ethylene oxide andpropylene oxide, which is a ring-splitting polymerization reaction at the catalysts.

采用带有空间位阻基团的脂肪胺在催化剂的作用下与环氧丙烷和环氧乙烷开环聚合，合成LY系列脱硫剂。

It showed that, compared with other catalysts, SO(superscript 2- subscript 4)/TiO2-ZrO2 was more active to bring about more than 95% conversion rate of stillingia oil under the transesterification conditions of 150℃, molar ratio of methanol to oil 12:1, catalyst amount 5% and reaction time 6h.

结果表明，催化剂SO(上标 2-下标 4)/TiO2-ZrO2表现出了较高的催化活性，SO(上标 2-下标 4)/TiO2-ZrO2催化的最佳酯交换反应条件为：反应温度150℃，醇油摩尔比12：1，催化剂用量5%，反应时间6h，此时乌桕籽油的醋化率超过95%，且催化剂重复和再生使用效果良好。

Solid acid catalysts such as S2O(superscript 2- subscript 8)/TiO2, S2O(superscript 2- subscript 8)/TiO2-ZrO2, SO(superscript 2- subscript 4)/TiO2-ZrO2, SO(superscript 2- subscript 4)/A12O3-ZrO2 were prepared and their catalyst activities for biodiesel production from stillingia oil were evaluated with the same condition.

通过对S2O(上标 2-下标 8)/TiO2、S2O(上标 2-下标 8)/TiO2-ZrO2、SO(上标 2-下标 4)/TiO2-ZrO2、SO(上标 2-下标 4)/A12O3-ZrO2 4种固体酸催化剂的制备，并在同一条件下比较了它们在乌桕籽油制备生物柴油反应中的催化活性。

The design, synthesis of crosslinked poly-salenCo complexes and their application in the HKR of terminal epoxides Di-salicylaldehydcs and tri-salicylaldchydes S-3, S-4, S-5 were synthesized from some easily prepared acids. The crosslinked polymeric ligands could be prepared by condensation of -1, 2-cyclohexanediamine stoichiometrically with a mixture of S-3 and S-4 in different proportions, polymeric catalysts were obtained by inserting the Co atoms to the ligands.

四 交联poly-salenCo络合物的设计合成及其在末端环氧化合物的HKR中的应用以几种易得的羧酸为骨架，设计合成出了相应的双水杨醛和三水杨醛S-3、S-4、S-5，将双水杨醛S-3和三水杨醛S-4按不同比例混合后再与手性环己二胺缩合制备出交联聚合物配体，该配体与Co络合后得到交联聚合物催化剂。

COD removal for succinic acid degradation was at the range of 54.4～98.3％ for different catalysts in 30 min.

催化剂在30 min内对丁二酸降解的COD去除率为54.4～98.3％。

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐