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The synthesis of methyl benzoate was carried out from acetophenone and dimethyl carbonate in the presence of solid acid and base catalysts.

以固体酸碱为催化剂，研究了碳酸二甲酯与苯乙酮合成苯甲酸甲酯的反应，考察了反应温度、反应时间、催化剂用量和原料摩尔配比等因素对反应结果的影响。

The results indicated that acetophenone can be reduced by NaBH4/BF3Et2O with high chemical yield and low to moderate enantioselectivity when amino alcohols were used as catalysts.

结果表明：这些氨基醇催化NaBH4/BF3Et2O还原苯乙酮可以获得很高的化学产率和低到中等的对映选择性。

It was found that copolymerization of selected acetylenes with different polarity by using palladium acetylide complex catalysts is an effective method for improving solubility of polymers, especially doped polymers, which makes the above mentioned polymers and doped ones a new type of π-conjugated sensing material for preparation of thin film humidity sensor.

研究发现，以新型过渡金属钯-炔配合物为催化剂，通过选择具有不同极性的取代乙炔单体进行共聚，可有效地提高聚合物的溶解性，尤其掺杂聚合物的溶解性，实现可溶酸掺杂，继而开发出上述系列新的π-共轭型聚炔湿敏材料，用以制备薄膜型湿敏元件。

ABSTRACT Homopolymerization and copolymerization of substituted acetylenes with different polarity by the transition metal acetylide complex catalysts PPO, Pd (PPh〓〓〓; PPB, Pd〓 C≡CC (CH〓〓OH 〓etc.

首次以过渡金属钯-炔配合物为催化剂（PPO，Pd〓〓；PPB，Pd〓〓等），实现了具有不同极性取代乙炔单体的均聚和共聚。

The effects of different catalysts, mole ratio of glyoxalic acid and urea on yield of allantoin are investigated.

以乙二醛、硝酸、尿素为原料，通过二步合成得到尿囊素，主要考察了缩合反应中，使用不同催化剂催化缩合尿囊素的收率对比及影响因素。

The hydrothermal method is used to obtain two types of TiO2 nanotube catalysts, to which the vitriol with different density is applied to acidify them.

利用水热法制备了两种TiO2纳米管催化剂，用不同浓度硫酸对制备得到的TiO2纳米管进行酸化。

Esides, Ce ions can accelerate the oxidation-reduction cycle of catalysts in the process of propane oxidation to acrolein.

i-Mo二元复合氧化物催化剂中添加适量的Ce和V组分可进一步提高催化剂晶格氧选择氧化丙烯生成丙烯醛的反应活性。

The catalysts used are inorganic acids, organic acids and its acyl halides, etc.

所用催化剂为常用的无机酸、常用的有机酸及其酰卤等。

In addition,the reaction conditions such as temperature,time,the ratio and catalysts were studied.

添加消泡剂已被证实是消除有害泡沫最有效和最经济的方法。

Additives rare earths can further improve activity and thermostability no matter Fe or Fe/Mn catalysts. Co adulterant of CeO2 and La2O3 can promote the activity and thermostability of manganeses mixed oxides for the reverse water gas shift reaction.

稀土助剂加入可进一步提高铁基催化剂的活性，无论是单独铁基催化剂还是Fe/Mn催化剂加入稀土助剂后催化剂的活性都不同程度的提高，同时加入CeO_2和La_2O_3助剂可以显著提高Fe/Mn催化剂的活性和热稳定性。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。