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The degree of hydrogenation of methyl benzoate might be controled by adding the promoters and changing the nano-size of ZnO. For hydrogenation of methyl benzoate to benzaldehyde, the active-structure of a catalyst should be modified to decrease the absorption of benzaldehyde on the surface of it, because benzaldehyde absorbed is hydrogenated easily. Using 30-40％ZnO/γ-Al〓O〓 or Li-30％ZnO/γ-Al〓O〓, a higher selectivity to benzaldehyde is obtained. Hydrogenolysis of methyl benzoate to toluene or benzene is carried out effectively using a catalyst modified. For instance, 45.3％ selectivity to benzene and 100％ conversion of methyl benzoate at 420℃ was obtained over 10％ZnO/MCM-41 with the nano-size particles of ZnO (2.4nm).

也可以通过助催化剂的添加和活性组分的纳米化，并根据苯甲酸甲酯多步加氢反应的特点实行加氢深度的调控：苯甲酸甲酯选择性加氢制苯甲醛中，由于苯甲醛容易进一步加氢，需要对活性结构进行调变，以减弱苯甲醛的吸附，使用30-40％ZnO/γ-Al〓O〓催化剂或Li调变的Li-30％ZnO/γ-Al〓O〓催化剂，可获得较高的苯甲酸甲酯加氢制苯甲醛的活性；采用同样的方式，苯甲酸甲酯选择性氢解为甲苯或苯也获得了较好的结果，如使用ZnO纳米化的10％ZnO/MCM-41催化剂，在420℃，可获得45.3％的苯选择性，苯甲酸甲酯完全转化。

This technology makes use of the catalyst, which is coated on the surface of the catalyst monoliths, to reduce activation energy during combustation. In this way, the combustion efficiency is improved and the pollutant emission is reduced.

催化燃烧技术是利用催化剂载体表面涂覆的催化剂来降低燃料燃烧的活化能，从而使得燃烧更易进行，这样不仅提高了燃烧效率，而且可以有效地降低污染物的排放。

Therefore,the study of how to reduce the catalyst monoliths temperature, choose proper monolith, and find its inner heat and mass transfer characteristics have great importance to reduce the emission of NOx, enhance combustion efficiency and prolong the service life of catalyst.

因此，如何降低催化剂载体的温度并选择适当的载体结构，研究其内部热、质传递规律，从而降低NOx的排放、提高炉内天然气燃烧效率及催化剂使用寿命无疑具有重要的现实意义。

The analysis of decomposition mechanisms of the catalyst surface revealed that one of the mechanisms is that activated gas phase O2 captures the hydrogen of the organic pollutants to produce free radicals, which then initiate the catalytic reaction, and produce CO2 and H2O ultimately; and the other mechanism is that the activated organic compounds attack the crystal lattice oxygen, which reduces the valances of the transition metals, then the oxidant of the oxygen oxidizes the transition metals to high valances, which realize the self oxidation-reduction of the catalyst.

催化剂表面有机物降解的机理分析表明，一种反应机理为气相中的O2活化后直接夺取有机污染物的氢，产生自由基，并引发催化反应，最终生成CO2和H2O；另一种反应机理为活化后的有机物直接进攻催化剂的晶格氧，并且使得过渡金属由高价态变为低价态，反应气中的O2再将低价态的金属氧化为高价态，实现催化剂自身的氧化还原循环。

The uptakes of H2 and CO on the Li-promoted Rh-based catalyst were almost the same as those on the Rh-Mn/SiO2 catalyst, which implied that most of Li was positioned on the support, and only a small part of the added Li was positioned on the top of Rh particles.

Li负裁量对Rh-Mn/SiO2催化剂上H2和CO的化学吸附量影响较小，这表明并非所有的Li都和Rh发生了相互作用，而是有相当一部分Li只是分散在载体SiO2上，并没有与Rh发生接触。

The present invention is a method to form a noble metal catalyst including two noble metals alloy on a catalyst support.

本发明涉及一种在催化剂载体上形成包括两种贵金属的贵金属催化剂的方法。

Differences in catalytic activity and ability to resist coking between noble metal based catalyst and Ni based catalyst are described.

介绍了贵金属催化剂与镍基催化剂在重整活性和抗积炭能力方面的差异。

Noble metal precursors, which are connected with the PM dispersion and stability of catalyst, have directly effect on the catalytic activity and durability of catalyst.

贵金属前驱体与贵金属在催化剂上的分散性和稳定性有密切的关系，直接影响催化剂的催化活性和耐久性。

Metal oxides which are present on the catalyst surface are converted in a conditioning step into metal sulphides, which provide the hydrogenation component of the bi-functional catalyst.

出现在催化剂表面的金属氧化物在预处理阶段转化为金属硫化物，该硫化物提供双功能催化剂的加氢成份。

Firstly, simultaneous removal of NO〓-C over mixture of metal oxides catalyst and carbon black was carried out with and without the assistanet of plasma. Secondly, catalysts loaded on γ-Al〓O〓 spherules were exposed to CA498 diesel exhausts to capture the PM, then the investigation into simultaneous removal of NO〓 and PM over catalyst with and without the assistant of plasma was conducted.

首先以复合金属氧化物催化剂和碳黑粉末的紧接触混合物为对象，进行等离子体／催化同时去除NO〓和碳黑的研究；然后以涂覆有催化剂的γ-Al〓O〓小球为载体，在实际柴油机尾气中挂烟，通过等离子体／催化作用，在模拟的富氧柴油机排气环境中，达到同时去除NO〓和微粒排放的目的。

There are different types of personal loans available.

有许多不同类型的个人贷款优惠。

The above mentioned teaching model of spiral rising can be used to avoid rigidness in teaching.

上述螺旋式上升的教学模式，可以避免教学形成模式後的僵化现象。