查询词典 catalysis

This paper reported the synthesis of 2-hydroxyl-1-naphthalene formaldehyde under microwave irradiation with 2-naphthol, hexamethylenamine, solvent of glacial acetic acide, catalysis of sulphuric acid, and discussed the influence of the time and the power of microwave radiation, the proportion and quantity of reagents to the synthetic yield.

利用微波技术，采用2-萘酚与六次甲基四胺为原料，冰乙酸作溶剂，在浓硫酸的催化下合成2-羟基－1-萘甲醛，并考察了微波作用的时间、微波辐射功率、反应试剂的组成与用量等因素对产物产率的影响。

A novel non - metallocene supported catalyst, CpTiCl2/MgCl2 - SiO2/ MAO ,was prepared, and the catalysis involved in ethylene homo - polymerization, ethylene - 1 - hexylene and ethylene - styrene copolymerization was investigated.

研究开发了一种新型非茂负载聚烯烃催化剂——CpTiCl2/MgCl2-SiO2/MAO，并考察了该催化剂的乙烯均聚、乙烯和1-己烯共聚及乙烯和苯乙烯共聚性能。

Both three-dimensional chiral compounds have intriguing chiral channels, which are built up of homochiral intertwined double helices. The circular dichroism spectra of 1 and 2 in water have shown they are stable in solution, which document they will be significantly useful in asymmetric catalysis and chiral medicine.

以Keggin结构多金属氧酸盐为建筑单元，通过手性的铜-脯氨酸配合物作为模板剂构筑了2个基于Keggin结构多金属氧酸盐的3D纯手性化合物，化合物1和2是一对对映体，代表了世界上第一例3D手性多酸化合物，具有由同手性螺旋缠绕形成的手性孔道，水溶液中的圆二色谱表征这个3D手性化合物可稳定存在，显示这个物种可以在不对称催化及手性药物方面有潜在的巨大的应用价值。

This result to will study the nanometer TiO2 surface hydrone adsorption mechanism and prevented the reunion all has the vital significance, simultaneously to explained the scientific researcher accepts the rice noodle body photochemical catalysis in TiO2 to respond observes certain phenomena will also have the help.

这一结果对研究纳米TiO2表面水分子吸附机理及其防止团聚都有重要意义，同时对解释科研人员在TiO2纳米粉体光催化反应中观察到的某些现象也将有所帮助。

Manganese dioxide is a familiar katalyst of oxidation reaction,there are five kinds of crystal configuration of manganese dioxide that have known, and different kinds of crystal configuration of manganese dioxide have the different catalysis and natural life.

二氧化锰是一种常见的氧化反应催化剂，现在已知二氧化锰有5种不同的晶型结构，不同晶型结构的二氧化锰的催化功能及寿命也不相同。

The immobilization of laccase is important for the fiber optic biosensor based on enzyme catalysis.

漆酶的固定化研究对基于漆酶催化的光纤生物传感器具有十分重要的意义。

The dissertation mainly consists of two parts:1. The Reaction Chemistry of Alkynes under Palladium Catalysis Part 1 studies the reaction α,β-unsaturated carbonyl compounds with alkenylpalladium intermediate generated by nucleopalladation, and discovered 1 the Pd-catalyzed tandem addition reaction of halides, alkynes and α,β-unsaturated carbonyls,2 the four-component tandem addition reaction of halides, alkynes and α,β-unsaturated carbonyls, 3 the tandem intramolecular oxypalladation-conjugate additionreaction of alkynoic acids with α,β-enals. These new reactions provide notonly efficient highly stereoselective methods for the synthesis of γ,δ-unsaturated,polyunsaturated carbonyl compounds and γ-lactonic aldehydes, but also thebasic transformations for a number of C-C bond formation reactions which can be usedto design synthesis of many acyclic, cyclic or polycyclic compounds.

本论文的主要工作分为两个部分：一、钯催化下炔烃的反应化学在本小组前人工作的基础上，我们详细研究了炔烃亲核钯化产生的烯基钯中间体与α，β-不饱和羰基化合物的反应，发现两价钯催化下卤离子-炔烃-α，β-不饱和醛酮的串联加成反应、卤离子-炔烃-α，β-不饱和醛酮的西组分串联加成及炔酸分子内氧钯化-串联Michael型加成反应；由此发展了γ，δ-不饱和醛酮、多不饱和羰基化合物和带有醛酮基侧链的γ-丁内酯衍生物的高立体选择性合成方法，这一过量卤离子存在下的烯基钯对α，β-不饱和羰基化合物共轭加成反应的发现，为大量碳-碳键形成反应的实现提供了基础，使我们能够从这一基本反应出发，设计和开发多种分子内、分子间的碳碳成键反应，以好的立体、区域选择性组建开链、环状及多环类型的化合物。

The research results also show that the electrical catalysis of the electrodes can be enhanced evidently when the electrodes are added some Nafion latex,but it also found that the Nafion latax made by different method has the different effects on the discharge voltage and current density of the ion exchange membrane fuel cells.

实验结果还表明，在电极中加入适量的Nafion乳液可显著地提高电极的电催化反应活性，同时也发现添加不同方法配制的Nafion乳液，对燃料电池放电性能的影响也有一定的差别。

For the first time, enantiomers of C2-symmetric 1,1 -spirobiindane-7,7'-diol were resolved with crude menthyl chloroformate by phase-transfer catalysis in the presence of tetrabutylammonium bromide. The reaction was carried out at 0℃-rt. The diastereomers of SPINOL bis-menthyl carbonate can be separated by simple crystallization using alcohol. The hydrolysis of the diastereomers was carried out via aqueous NaOH/EtOH solution.

首次通过相转移催化的方法对螺双二氢茚二酚进行了有效的拆分，用L--氯甲酸薄荷醇酯做拆分剂，以四丁基溴化铵为催化剂在0℃-室温下进行酯化反应生成非对映体衍生物，以乙醇作溶剂，通过重结晶的方法分离衍生物，在水-乙醇混合溶剂条件下，用强碱NaOH或KOH分别水解，制得相应的光学纯度大于99%ee的两个异构体SPINOL，其中总收率：--SPINOL，78.2%；--SPINOL，80.6%。

The optimal reaction parameters of methanolysis of soybean oil by lipase-catalysis weredetermined as follows: 15wt% of lipase, 55℃of temperature, petroleum ether as solution,methanol was added by 6 times.

对酶法催化豆油和地沟油的对比没有显著差异，说明脂肪酶是催化游离脂肪酸含量高的油脂生产生物柴油的有效催化剂。

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