活性中心

Fe2O3 acts as an activator more than a catalyst in the desulfurization reaction with lime. Fe2O3 acts as the "activation center" around which CaO particles are sulfurized. The new dispersal formation mode of product differs from the compact layer that used to be. And the pore structure of product layer on the surface of lime particles is optimized, which makes SO2 penetrate into core parts of lime more easily. As a result, the desulfurization reaction is developed deeper into the core parts of absorbent.

氧化铁所起的是改变石灰颗粒表层產物生成方式的活化作用，使反应生成物不会形成一个致密的外壳，而以氧化铁为活性中心进行硫化反应，形成了分散的硫酸钙產物堆积，改善了硫化过程中的表面孔隙结构，减少了石灰颗粒表面硫化產物层对反应气体向石灰颗粒內部扩散的阻力。

It was found that heme-iron of myoglobin directly interacted with additional Cu, Zn and Co, these metal ions could drag iron ion out from heme prosthetic group of myoglobin, and subsequently myoglobin became myoglobin derivatives lacking iron ion.

结果发现，金属离子M与肌红蛋白活性中心的Fe发生了直接相互作用，外加金属离子将铁离子从肌红蛋白中&拖拽&出来，形成部分空位肌红蛋白衍生物。

In addition, the bridging alkyls would provide a closer ion pair relative to the Ni center, thus causing chain transfer process to occur readily.

同时，TMA和TIBA比MAO更易导致链转移甚至使活性中心失活，因而TMA含量越高或外加TIBA，后期的聚合速率下降得越快。

The four most common types are a free-radical, carbanion (carbon-centred negative ion), carbocation (carbon-centred positive ion) or a metal complex (as in Ziegler-Natta polymerisation).

有四种最常见的活性中心类型：自由基、碳负粒子、碳阳离子鎓和金属络合物（在Ziegler-Natta聚合中使用）。

These active centers play many important roles in biological system, such as oxidation-reduction, electron transfer, catalyse of lewis acid.

这些活性中心在生物体中扮演着许多重要角色，如氧化还原、电子传递、路易斯酸催化等。

Thus, cyclohexene species can desorb quickly from the active sites, avoiding its deep oxidation dehydrogenation.

催化剂的表面上，使催化剂表面形成孤立的活性中心，避免了产物环己烯的深度氧化。

However TGase activity did not change significantly by increasing Zn2+ initial concentration.TGase activity did not change significantly when the fermentation culture was dialysed with EDTA addition. according to the change of biomass at different Zn2+ initial concentrations, the author considered that Zn2+ was not the component or active centre of TGase.

EDTA透析对TGase的酶活没有产生明显影响，结合不同Zn2+含量时SK4.001生物量的变化，作者认为，Zn2+在SK4.001发酵产TGase中同时具有营养和促进SK4.001产TGase的作用，但Zn2+并不是TGase的构成部分或活性中心，有关Zn2+促进SK4.001产TGase中的具体作用机理仍有待进一步研究。

This makes Ni-W-P powder more suitable for partial hydrogenation of dienes. The kinetic results suggest there are some different between the active sites of Ni-P and Ni-W-P powder. DSC, XRD and EXAFS results suggest that the tungsten codeposition makes Ni-W-P powder more amorphous than Ni-P powder.

动力学结果表明在两种合金微粒上，不仅环戊二烯与环戊烯的相对配位能力不同，而且它们各自的反应速率常数也不一样，表明非晶态Ni-P、Ni-W-P合金微粒的催化活性中心存在着一定的差异。

It is a very basic, single-chain protein with molecular weight about 14 kD. It shares 33% sequence identity with bovine pancreatic RNaseA and has structurally equivalent counterparts for the two histidines and one lysine that comprise the catalytic residues for ribonucleolytic activity.

它是由123个氨基酸组成的分子量约为14kD的单链碱性蛋白质，与牛胰核糖核酸酶有33％的同源性，两个组氨酸和一个赖氨酸残基组成了血管生成素核糖核酸酶活性中心。

We can find that the conformational change of active site ofRubisco is faster than that of holoenzyme.

比较酶的失活与构象变化，发现酶的活性中心构象变化先于整个酶分子的构象变化。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。