查询词典 catalyst

It is demonstrated that, in one aspect, in-situ zeolite has more effective catalytic capability based on unit active site, in another aspect, it has excellent ring-open activity as so called in-situ type hydrocracking catalyst can produce tail oil with generally 2-3 unit lower than traditional hydrocracking catalyst on BMCI index.

实验结果表明，原位分子筛材料不仅表现了具有更高本征催化效率的特点，而且突出表现了优异的开环裂解性能，所涉及的所谓原位型加氢裂化催化剂能获得比常规催化剂低2～3个单位的低BMCI值尾油。

Due to the suppression of reverse water gas shift reaction by adding steam in feed gas, more CO〓 participated in and promoted CO〓 reforming of CH〓 reaction, higher catalytic activity and less carbon deposition were obtained. On the surface of used catalyst there were two kinds of carbon species deposited on catalyst, one was decomposed CH〓 fragment, and the another was graphiticlike carbon.

在反应后催化剂表面有两类碳物种，一类在250～350℃出现的少量α-碳，应主要是活性高的CH〓解离碎片，一类是在700℃附近出现的β-碳，应是导致催化剂失活的类石墨化碳。

A Ni/Ce-Zr-Al-Ox catalyst was prepared by hydrothermal synthesis－impregnation method. The CO2 reforming of CH4 reaction was performed. By XPS and TPH methods the carbon species deposited on the surface of catalyst during the reaction were characterized; The effect on the carbon deposit by adding a small amount of steam in feed gas and the interaction between steam and carbon species were studied.

采用水热合成-负载法制备了Ni/Ce-Zr-Al-Ox催化剂，进行了CO2重整CH4的反应，并采用X射线光电子能谱、程序升温加氢等方法表征了在反应过程中催化剂表面的积碳物种，考察了添加少量水蒸汽对积碳的影响以及水蒸汽和表面积碳物种的作用。

The concrete steps are: the lactic acid and small-molecule dicarboxylic acid react under the condition with the presence of the catalyst to directly polymerize the carboxyl-terminated lactic acid prepolymer; then the aliphatic polycarbonate diol and the catalyst are added; with the presence of the N2, the reaction is kept for 1 to 10 hours at the temperature of 150 to 200 Celsius system to get the poly lactic acid and polycarbonate copolymer of the low molecular weight; then the reaction is done in the twin-screw extruder at the temperature of 150 to 190 Celsius system to screw out the extension chain; finally the polylactic copolymer of the high molecular weight, toughness and heat resistance is made.

具体步骤是：乳酸和小分子二元酸在催化剂条件下反应直接缩聚合成羧基封端的乳酸预聚物，然后加入脂肪族的聚碳酸酯二元醇和催化剂，在N 2 气氛下，抽真空，在150～200℃温度下，反应1～10小时，得到低分子量聚乳酸/聚碳酸酯共聚物，然后在双螺杆挤出机中在140～190℃下，进行反应挤出扩链，最终得到高分子量的、韧性与耐热性较好的聚乳酸共聚物。

In the present invention, platinum-carbon catalyst, perfluoro sulfonic acid resin solution and absolute ethyl alcohol are uniformly mixed under ultrasonic conditions; mixture is uniformly smeared on a micro-porous layer of carbon cloth or carbon paper in a brushing or printing method, and a traditional Pt/C gas porous electrode is obtained after drying; silicon oil is adopted to infiltrate into pores of a catalyst layer and a diffusion layer of the traditional Pt/C gas porous electrode, and then the ordering anti-drowning gas porous electrode is obtained after drying.

本发明是将铂碳催化剂、全氟磺酸树脂溶液和无水乙醇在超声波条件下混合均匀，采用涂刷或印制的方法将混合物均匀涂布到碳布或碳纸的微孔层上，干燥后制得传统Pt/C气体多孔电极；然后将硅油渗入到传统Pt/C气体多孔电极的催化层和扩散层孔隙中，干燥后制得有序化抗溺水气体多孔电极。

A method for making Bisphenol A with a purity of more than 99.7% by reacting phenol and acetone using an acid catalyst, separating a BPA-phenol adduct by crystallisation and removing phenol from the adduct, in which involves continuous suspension crystallisation with a total dwell time of more than 4 hours in at least 3 crystallisers, by cooling first to 50-70 C in two parallel crystallisers and then to 40-50 C in a third crystalliser connected in series with the first two.; A method for the production of Bisphenol A with a purity of more than 99.7%, by reacting phenol with acetone in presence of an acid catalyst, separating a BPA-phenol adduct from the product mixture by crystallisation, filtration and washing, and removing the phenol from the adduct, in which stage involves continuous suspension crystallisation in at least three crystallisers connected in such a way that the mixture is first cooled to 50-70 C in two crystallisers in parallel and then cooled to 40-50 C in a third crystalliser in series with the first two, the total residence time of the mixture over all crystallisers being more than 4 hours.

描述用于生产纯度大于99.7％的双酚例如，双酚A(BPA的方法，这种方法包含苯酚和丙酮在有酸性催化剂参与的情况下反应形成一个包含双酚的产物混合物；通过结晶、过滤和洗涤从该产物混合物中以双酚/苯酚复合物的形式除去至少一部分双酚以提供双酚A/苯酚复合物晶体；并且从双酚/苯酚复合物晶体中除去至少一部分的苯酚以提供纯度大于99.7％的双酚；其中结晶过程包括连续的混悬液结晶，并且是在至少三个结晶装置中进行的，装置的排列使得产物混合物首先在结晶过程的第一阶段在第一个结晶装置和并联的第二个结晶装置中被冷却到50至70℃的温度，随后在结晶过程的第二阶段在与第一和第二个结晶装置下游串联的第三个结晶装置中被冷却到40至50℃的温度，并且其中产物混合物在结晶过程中的总驻留时间在4小时以上。

Optimum conditions are as follows: DMF is used as solvent, compound quaternary ammonium salt as catalyst, n(p-nitrochloro benzene):n=1: 1.2, m:m(p-nitrochloro benzene)=4%, m:m(p-nitrochloro benzene)1:1, and reacted under 155~160℃ for 18 h; reduction reaction is carried out in methanol with Raney nickel, which is used as catalyst; the raw product is added an antioxidant, and distilled simply under reduced pressure to obtain 4-fluoroaniline with excellence quality, purity is over 99.5%, total yield is 89.3%.

实验结果表明，氟化反应的最佳条件为：二甲基甲酰胺为溶剂、复合季铵盐为催化剂，n：n=1：1.2，m（催化剂：m=4%，m：m=1：1，于155~160℃下反应18h；还原反应在甲醇中进行，以阮内镍为催化剂；粗产品加入抗氧剂，减压条件下简单蒸馏得高品位的对氟苯胺。

In this work, supported gold catalyst was studied as the CO PROX catalyst. The effects of supports, preparation parameters, pretreatments and H2O/CO2 on the catalytic property were carried out.

因此负载型Au催化剂在选择氧化消除富氢气氛中的CO方面有着很大的潜力，这就预示着其在PEMFC中有着十分广泛的应用前景。

When the heterogeneous catalyst is used in the asymmetric catalytic hydrogenation reaction of ethyl pyruvate under the room temperature and the medium hydrogen pressure, high activity and optical selectivity more than 70 percent are obtained in acetic acid solution, and the heterogeneous catalyst can be repeatedly used for more than 15 times.

本发明提供的催化剂在室温、中等氢压力下用于丙酮酸乙酯的不对称催化氢化反应时在乙酸溶剂中可得到高活性和超过70％的光学选择性，且可以重复使用15次以上。

Catalyst ; sec-butyl alcohol ; methyl ethyl ketone ; dehydrogenation ; BC-DH2004 catalyst

催化剂；仲丁醇；甲乙酮；脱氢； BC-DH2004催化剂

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