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The structure of IC with wood and its constitutes was also studied by Fourier Transform Infrared Spectroscopy. It shows that the reaction of IC with lignin mainly produces carbamate, when lignin contains some water, produces weak carbamide; but the reaction of IC with wood powder produces weak carbamite, and with the wood powder containing water mainly produces carbimide.

对于异氰酸酯与木材及其组分反应产物的结构，论文采用傅利叶红外谱图进行了分析，结果表明，木素与异氰酸酯反应主要生成氨基甲酸酯，含水率较低时有少量取代脲产生；木粉与异氰酸酯反应生成的氨基甲酸酯较少，含水木粉与异氰酸酯主要生成取代脲。

The higher the degree of external hydrogen-donation is, the easier the reaction is.③Thiophenes can be alkylated by the carbonium ion born in the reaction, and they can be polymerized on the strong acid sites.

噻吩类化合物可与反应过程中产生的正碳离子发生烷基化反应；在含有强酸性中心的催化剂上，噻吩类化合物之间还会发生一定程度的缩合反应。

Reaction trends of catalytic desulfurization of thiophene were determined based on the reaction energy needed, which was obtained with the AM1 calculation results of thiophene and possible carbonium ions on transition state.

采用半经验AM1计算方法，利用静态理论对噻吩在分子筛催化剂上的催化裂化脱硫机理进行了量子化学计算研究，通过对噻吩分子和可能产生的中间正碳离子的量子化学计算，得到各中间反应所需的能量，从而判断噻吩催化裂化脱硫反应的趋势，证实了氢转移反应在催化裂化脱硫中所起的作用。

According to Wurtz reaction, if we can control solvothermal reactive condition to make the four C-Cl bonds in the carbon tetrachloride broken incompletely, according to the mechanism of Wurtz reaction, some kinds of free radicals or carbonium ions will be produced in solvothermal condition.

那么，如果控制反应条件，使四氯化碳等小分子碳氯化合物中的氯原子不完全脱掉，根据Wurtz反应机理，反应体系中将产生大量的碳氯自由基或碳正离子，它们在溶剂热条件下按照一定的生长规律进行组合，必将生成大量的多氯代多环芳香化合物。

Experiment showed that the hydrolysis product of chloroisopentene in sodium hydroxide solution was mixture of isopentenol and methyl butenol , which indicated that displacement reaction of chloroisopentene was accompanied by isomerization reaction of carbonium ion.

在以氢氧化钠水溶液进行氯代异戊烯水解时发现，水解产物为异戊烯醇和甲基丁烯醇的混合物，这说明氯代异戊烯在进行取代反应的同时，伴有正碳离子的异构化反应，由此开发了一条全新的由氯代异戊烯生产甲基丁烯醇和异戊烯醇的新的工艺路线。

The effect of zeolites ion-exchanged by transition metals on thermal catalytic cracking reaction is studied. The product distributions of the cracking reactions catalyzed by theβor ZSM-5 zeolites exchanged with transition metals are different from that catalyzed by corresponding Hzeolites, which means the mechanism of cracking reactions has varied. Group Ⅷ metals Fe, Co, Ni and Cu, Zn are shown to be of strong catalytic activity of oxidative dehydrogenation, while Ti and Cr are not of oxidative activity. Catalyzed by zeolites or catalyst containing Ag, conversion of thermal catalytic cracking reactions and the yield of ethylene increase while the yield of propylene does not decrease. Silver can not only promote the formation of carbonium ion, but also convert carbonium ion into free-radical via redox reaction. The weak adsorption of olefins on silver reduces the occurrence of hydrogen transfer and dehydrogenation. As a result, the yield of light olefins is favored by silver in the catalyst.

采用过渡金属交换的分子筛作为催化剂，进行催化热裂解制取乙烯的反应，研究发现，在β沸石分子筛和ZSM-5分子筛中引入过渡金属后，催化热裂解反应的产物分布与相应的氢型分子筛相比有了较大的变化，说明过渡金属的加入对于催化热裂解反应的机理具有影响，Ⅷ族金属如Fe、Co、Ni和第Ⅰ、Ⅱ副族Cu、Zn表现出较强的氧化脱氢活性，产物中氢气、焦炭的产率很高，Ti、Cr则未表现出氧化作用：分子筛及催化剂中引入银后，催化热裂解反应的转化率和乙烯的产率有了提高，丙烯产率没有很大的变化，说明银在催化热裂解反应中能够促进正碳离子的生成，又有可能通过氧化-还原作用部分改变反应机理，促进了自由基的生成，并且由于银对烯烃的吸附很弱，其氢转移反应和脱氢、加氢活性比较低，有利于烯烃产率的提高。

An enzyme is a protein that catalyses or accelerates a biochemical reaction without altering the nature of the reaction.

酶是一种蛋白物质，在物质没有发生自然反应时可促进并加速其进行生化反应。

Moreover, CaO catalyses the steam reforming reaction of hydrocarbons and the water-shift reaction.

CaO能够促进泥炭的裂解，并对烃类的重整反应和水煤气变换反应起到催化作用。

ResultThe maximumabsorption wavelength of reaction solution was about 720nm.The fermentation volume,adding the activated carbonor not,pHvalue of reaction solution and so on had no great effect onthe determinationresults and they could increase the screening efficiency.The effect of ultrasonic treatment for20min was obvious.When50ml volumetric flask was used,the suitable sampling volume was 2.5ml.It was better to centrifugate the fermentationliquid and the supernatant could be taken after standing inthe determination when necessary.

结果反应液最大吸收波长在720nm左右；发酵体积、加入活性碳与否、反应液的pH值等对测定结果影响不大，在筛选时可大大提高效率；超声波处理20min效果明显；在用50ml容量瓶进行定容时，取样体积以2.5ml为宜；对发酵液进行离心效果更好些，但在必要的情况下，可静置后取上清测定。

Multiple-walled carbon Nanotubes were used as carrier to load cerous sulfate catalyst for catalytic synthesis of n-butyl propionate Single factor and orthogonal experiment methods were applied to investigate the effects of the molar ratio of butyl alcohol to propionic acid, cerous sulfate mass fraction and reaction time on the conversion of propionic acid and the optimal technical conditions were determined as:ratio of butyl alchhol and propionic acid 1.5:1, cerous sulfate mass fraction 15% and reaction time 70 min.

以多壁碳纳米管作载体担载硫酸铈催化合成丙酸丁酯。分别采用单因素和正交实验方法考察了醇酸摩尔比、硫酸铈质量分率和反应时间等主要因素对丙酸丁酯得率的影响，并确定了最佳工艺条件为：醇酸摩尔比1.5：1、硫酸铈质量分率15%和反应时间70 min。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。