查询词典 selectivity

However, in S8/MAO catalytic system, the polymer was produced as main product and the activity and the selectivity of ethylene trimerization was very low.

然而，对于S8／MAO催化体系，却不能选择性催化乙烯三聚，主要生成高聚产物。

Due to the hemilability of the heteroaromatic functionalized cyclopentadienyl ligand, these complexes showed considerable activity and high selectivity for ethylene trimerization to 1-hexene.

由于这类芳香杂环-茂配体具有Hemilabile特性，因此，此类络合物显示了一定的乙烯三聚活性和高的三聚选择性。

HNC_2H_4S C_(12H_(25)_2·CrCl_3 and Et_2ZrCl_2 were supported on SiO_2 and the effects of different supporting strategies on trimerization selectivity, 1-hexene incorporation efficiency and copolymerization activity were studied and compared to the homogeneous system.

当R基为-C_2H_5时，1atm下65℃时活性最高可达550kg hexene／，提高反应压力有助于得到更高的活性，但是会降低催化剂的选择性；当R基为-C_(12)H_(25)时，1atm下75℃时活性最高可达450kg hexene／。

The reaction results show that the catalytic activity and selectivity of W-HMS prepared with tungstic acid is better than that prepared with sodium tungstate. And the consumption of t-BuOH also is successfully reduced.

实验结果表明：钨酸是制备W-HMS催化剂很好的钨源，以钨酸为原料制备的催化剂具有很高的催化活性和选择性，使溶剂叔丁醇用量大为减少。

CO conversion of 80.27%, 78.41% and 61.14% and selectivity to C(superscript + subscript 5) of 88.54%, 88.57% and 77.95%, respectively, were obtained for Fischer-Tropsch synthesis under n(H2): n=2.0, 483 K, 1.5 MPa and 800h^(-1) over uncalcined catalyst, those calcined at 673 K and 923 K.

在原料气n(H2)：n=2.0、483K、1.5MPa和800h^(-1)条件下，未焙烧、673K和923K焙烧的催化剂上进行F-T合成反应，CO的转化率分别为80.27%、78.41%和61.14%，重质烃的选择性C(上标+下标 5)分别为88.54%、88.57%和77.95%。

The catalytic activity is much higher than that of the unpromoted sample Fe/Zr, while light olefins selectivity decreases and methane formation increases.

催化剂的催化活性比Fe/Zr及Fe/La催化剂都大大提高，甲烷选择性也有所增加，烯烃选择性降低。

Unpromoted α-MoC(subscript 1-x) produced mainly CO2 and light hydrocarbons, addition of K2CO3 as a promoter, however, resulted in remarkable selectivity shift from hydrocarbons to alcohols.

结果表明，K改性使α-MoC(下标 1-x)催化剂的CO加氢选择性发生显著变化。

DNA recombinant technology have brought innovation to the biolog y technology, it can supply the strains with strong selectivity and ability of accumulating target metabolites.

摘 要 重组DNA技术使生物技术取得了彻底性的变革，它可以提供具有极强选择性和累积目的代谢物能力的菌株。

At 275℃, with Al2(SO4)3/K2SO4 mixed catalyst, which the mass ratio was 15:85, the conversion ratio of propylene oxid could be as high as 97.60%, and the selectivity of propionaldehyde was 94.57

其中有如Al2(SO4)3/K2SO4(质量比15∶85)混合型催化剂在275℃时，环氧丙烷转化率达到97.60%，丙醛选择性达到94.57

The present invention is method of synthesizing high selectivity adsorbing material by means of molecular print technology and the advantages of silicon ball.

本方法是利用分子印迹技术和硅球内在的优点合成高选择性的吸附材料。

In the negative and interrogative forms, of course, this is identical to the non-emphatic forms.

。但是，在否定句或疑问句里，这种带有"do"的方法表达的效果却没有什么强调的意思。

Go down on one's knees;kneel down

屈膝跪下。。。下跪祈祷