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Due to the ability of the bivalent magnesium cation to form stable chelate complexes with carbonyl compounds,magnesium methylate for example is used as a selective carbonyl condensing agent. Three synthesis routes was proposed based on literatures and comprehensive comparison with other ways. First,Magnesium methylate is prepared by reacting magnesium metal with dry methanol.The magnesium salts of"higher"primary alcohols,i.e.alcohols with ≥ 2 carbon atoms,do not react directly with pure alcohols under normal conditions.In fact catalysts are required to set the reaction in motion and the preparation is performed under pressure at the higher temperatures.

一、直接合成法：本文将镁与无水甲醇直接反应制得甲醇镁；"更高级"的醇（比如C≥ 2的醇）在无催化剂的条件下无法直接和镁进行反应，本文以CCl4为催化剂将无水乙醇与镁直接反应制得乙醇镁，但是以原甲酸三乙酯为催化剂无水乙醇与镁无法反应；不论是以CCl4为催化剂还是以原甲酸三乙酯为催化剂，丙醇均无法与镁直接反应。

Due to the ability of the bivalent magnesium cation to form stable chelate complexes with carbonyl compounds,magnesium methylate for example is used as a selective carbonyl condensing agent.Three synthesis routes was proposed based on literatures and comprehensive comparison with other ways.First,Magnesium methylate is prepared by reacting magnesium metal with dry methanol.The magnesium salts of higherprimary alcohols,i.e.alcohols with ≥ 2 carbon atoms,do not react directly with pure alcohols under normal conditions.In fact catalysts are required to set the reaction in motion and the preparation is performed under pressure at the higher temperatures.

一、直接合成法：本文将镁与无水甲醇直接反应制得甲醇镁；"更高级"的醇(比如C≥2的醇)在无催化剂的条件下无法直接和镁进行反应，本文以CCl_4为催化剂将无水乙醇与镁直接反应制得乙醇镁，但是以原甲酸三乙酯为催化剂无水乙醇与镁无法反应；不论是以CCl_4为催化剂还是以原甲酸三乙酯为催化剂，丙醇均无法与镁直接反应。

Therefore, in this paper, the process for preparing 2,6-DMN by methylation of methylnaphthalene over AlClx/HY and AlClx/HY-U zeolite catalysts is employed. The effects of reactions conductions on reaction results were studied.

为此，本文采用2-甲基萘烷基化的合成路线，考察了AlClx/HY型和AlClx/HY-U型分子筛的反应活性，以及反应条件的影响。

The glassy carbon and powder microelectrode have respective trait. It can be chosen to measure the activity of catalysts based on experimental requests.

玻碳电极和粉末微电极各有特点，测试催化剂的电催化活性时可以根据实验要求选用。

The cyclic voltammetric behavior of platinum-ruthenium alloy catalysts was studied by using the powder microelectrode technique and glass carbon electrode.

利用玻碳电极和粉末微电极测试甲醇在Pt-Ru/C催化剂上的循环伏安曲线。

Molybdenum carbide catalysts were prepared by temperature-programmed reaction using CH4/H2 gas mixture to carburize molybdenum trioxide at different temperatures, then were characterized with XRD and BET.

以MoO3为前躯体，CH4/H2为还原碳化气，采用自制的程序升温还原碳化反应装置制备出Mo2C催化剂，并用XRD、BET进行表征。

Some molybdenum compounds (in which it has various valences) are used as pigments and catalysts.

有些钼的化合物(钼在化合物中可以有不同的原子价)可以做颜料和催化剂。

Some molybdenum compounds (in which it has various valence s) are used as pigments and catalysts.

有些钼的化合物(钼在化合物中可以有不同的原子价)可以做颜料和催化剂。

Latest advances in studies on mechanisms for hydroisomerizaton of n-alkane over bifunctional catalysts supported on zeolites,including monomolecular and bimolecular reaction mechanisms, pore mouth mechanism and key-lock mechanisms,were reviewed.

综述了近年来正构烷烃在分子筛为载体的双功能催化剂上加氢异构化反应机理的研究进展，介绍了单分子机理、双分子机理、孔口机理及锁匙机理，并展望了反应机理在制备新型催化剂领域的应用前景。

The impact of catalysts on naphtha catalytic cracking was investigated.

考察了催化剂对石脑油催化裂解的影响。

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