催化作用

All the above catalysts were used also in the methoxycarbonylation of thiophene.

由此推论这些负载催化剂的催化性能均来自于协同作用。

The experiment in vitro of killing cervical cancer cells was carried out by using TiO 2 photocatalytic method.

应用二氧化钛光催化的方法在体外对宫颈癌细胞进行了杀灭试验，结果显示，二氧化钛在光照下对宫颈癌细胞有明显的杀灭作用。

In specific acid catalysis, the undissociated acid s do not contribute

在特殊的酸催化中，不离解的酸不起作用。

In specific acid catalysis, the undissociated acids do not contribute.

在特殊的酸催化中，不离解的酸不起作用。

The experimental results show that Mn2O3 was main active species and addition of Zr further activated methane molecules to improve methane conversion; C2 selectivity was improved by adding W and P, and suppressed deep oxidation property of SiO2; W–O in catalyst surface was not active species.

通过选取五组该催化剂对其进行XRD、XPS、FT-IR以及SEM表征，表明Mn2O3和Na2Zr(PO4)2是多组分甲烷氧化偶联催化剂的活性组分，且Mn2O3起主要作用，Zr的加入进一步活化了甲烷分子，提高了甲烷的转化率，W和P的加入改善了C2烃的选择性，抑制了SiO2的深度氧化特性；W–O物种不是催化活性物种。

Such a viewpoint of the effects of a little water addition has never been reported, it opened a new way to product SWCNTs with high purity and low cost. On the ground of the experimental results and mechanism studies, a little water addition may open a way for using the natural gas as carbon source to manufacture SWCNTs. By analyzing XRD, XPS results and with comparative experiments, we concluded that the active phases of SWCNTs growth in Ar were small Fe particles. A little W species can improve the surface characters of support and increase the dispersion of Fe particles, but higher W loading will cause large quantity of WC, which decompose CH〓 to amorphous carbon.

本文根据W-Fe-MgO催化剂中间产物和粗产物的XRD、XPS测量结果，结合制备实验和对比实验指出：在Ar中1073K下，生长SWCNTs的活性相是Fe的小颗粒，少量W在催化剂中以氧化物形式对载体表面改性，起提高Fe分散度的作用，但W浓度过高时在反应过程中会生成大量WC，又会催化CH〓分解为无定形碳，造成产物中SWCNTs含量下降。

Methods Ascorbic acid was determined by inhibition kinetic spectrophotometric method, which was based on the inhibition effect of ascorbic acid on the nitrite catalyzed oxidation of xylenol orange by potassium bromate in dilute sulfuric acid medium.

在稀硫酸介质中，利用抗坏血酸对亚硝酸根催化溴酸钾氧化二甲酚橙的阻抑作用，用阻抑动力学光度法测定抗坏血酸。

The phase structure of zirconia is important for many catalytic reactions and materials.

氧化锆的晶相结构对其在催化反应中的活性以及作为材料的性能有着决定性的作用，氧化锆体相晶相结构的研究已有很多文献报道，但针对其表面。。。

C. 1. 11. 1. 6 is an enzyme present in the cells of all aerobically living organisms, which catalyses very efficiently the decomposition of hydrogen-peroxide into water and oxygen. Catalase exerts various physiological functions.

它广泛存在于好氧细胞中，其主要的生理作用就是催化H〓O〓分解为H〓O和O〓使得H〓O〓不致于与超氧化物自由基反应生成非常有害的·OH。

Compared with the previous method, the improved route can provide directly a spheroid form of immobilized lipase particles of which the size can be controlled by adding non-ionic surfactants during the preparation process so as to increase the recovery rate of enzyme as well as decrease the external diffusional restriction which can diminish the enzyme activity. The improved method can also alter the hydrophobicity and microstructure of the immobilized enzyme matrix by changing the molar ratios of different alkoxyl silanes so as to enhance the enzyme activity by a"surface active effect"and eliminating the internal diffusional restriction.

与前人的制备方法相比，改进的方法可直接制得球形的固定化酶颗粒，而且颗粒的大小可以通过在制备过程中加入非离子型表面活性剂加以控制，从而可以提高固定化过程的酶活回收率和减小外扩散效应对酶的表观催化活力的影响；改进的方法还可以通过改变原料硅氧烷的种类及配比来改变最终制得的固定化载体的疏水性质及微观结构，从而通过对脂肪酶的&界面活化&作用和减小内扩散效应提高固定化脂肪酶的表观酯化活力。

She gently rebuff ed him, but agreed that they could be friends

她婉言拒绝了，但同意作为朋友相处。

If in the penal farm, you were sure to be criticized.

要是在劳改农场，你等着挨绳子吧！