查询词典 catalysts

This type of catalysis advantageously replaces the conventional catalysts based on mercury salt.

这类催化有利地代替以汞盐为主要成分的通常催化剂。

In order to examine the catalytic activity of the new catalysts, we have carried out the direct asymmetric Aldol reaction of tetrahydro-4H-thiopyran-4-one with aldehydes.

催化剂的基本结构单元如下：为了检验新型有机催化剂的催化活性，我们研究了硫代四氢吡喃酮和各种醛的直接不对称Aldol反应。

The catalysts used in the preparation of di acetone alcohol by the Aldol condensation were studied in detail, and a new kind of catalyst Ca 2/Al 2O 3 is developed.

对丙酮经Aldol缩合制二丙酮醇的催化剂进行了研究，研制出新型催化剂Ca 2 /Al2 O3，这种催化剂对丙酮的缩合反应具有较理想的活性及选择性。

The effect of alkaline metal, alkaline-earth metal or rare-earth metal oxides doping to Pd/γ-Al〓O〓 on the properties of supported palladium catalysts were investigated.

研究含氧条件下单Pd催化剂上进行丙烯选择催化还原NO的反应，考察浸渍法制备的Pd/γ-Al〓O〓催化剂中加入碱或稀土金属氧化物助剂对NO转化率的影响，并对催化剂进行了XRD表征及在氧化气氛中饱和吸附NO后的TPD研究。

Therefore, the study on bifunctional catalysts and their application in alkane conversion is necessary.

因此，对催化烃转化反应的双功能催化剂的研究就显得十分重要。

In the contrast, the effect of the kind of catalysts on oxidation of alkane under mild condition has been paid little attention.

相比之下，在氧化条件下，对此类催化剂催化烷烃反应研究的不多。

Long-chain alkene is adsorbed on the surface of catalysts much more strongly than benzene is adsorbed.

长链烯烃在催化剂上的吸附比苯要强得多。

These results indicated that the separation of the alkylate and the ionic liquids was easy and the loss of aromatics out from the catalysts was inevitable.

实验结果显示烷基化产品与催化剂分离方便，但芳烃助剂的流失不可避免。

Combining the performance evaluation (activity, selectivity and stability) and the characterization of the catalysts (XRD, TPD, FTIR and the pore structure measure), it can be concluded that :(1)The activity of modified β is higher than MCM-22, but the selectivity of ethylbenzene is lower about 3% than that of MCM-22;(2)The mounts of diethylbenzene and the other by-products are higher 1.7 times and 1.5 times than these of MCM-22 respectively;(3)The catalytic performance of zeolite mixture is nearly equal to modified β, but the selectivity of ethylbenzene is higher about 0.5% than that of modified β;(4)The catalytic activity of zeolite is mainly correlated with the number of acid sites, strength and distribution, and the distribution of products is determined by the binding energy of ethylbenzene and the pore structure, while the stability of catalyst is affected by the amount of poly-ring aromatic alkylate and the pore structure.

以性能评价和特性表征（XRD、TPD、FTIR和孔结构测定）相结合的方式，对上述三种催化剂性能比较的结果表明：（1）改性的活性明显高于MCM-22，但乙苯选择性却低于MCM-22绝对差约3%；（2）改性(上二乙苯和其他副产物的生成量分别约为MCM-22上对应值的1.7和1.5倍左右；（3）混合型催化剂的性能与改性相仿，但乙苯选择性提高0.5%左右；（4）对乙苯合成，沸石催化剂的活性主要取决于其B酸中心数、酸强度及酸分布，产物分布则取决于催化剂表面的乙苯脱附能垒值和孔道结构，而稠环芳烃的生成量和催化剂孔道结构是影响催化剂稳定性的主要因素。

The results obtained provide basic thermodynamic data for studying alkylation of phenol with DEC and developing catalysts for it.

为烷基化反应条件的控制和催化剂的探索研究提供了热力学依据。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。