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In the presence of acetic acid and polyethylene glycol, chromic anhydride and acenaphthene react under mild condition and acenaphthene can completely convert into acenaphthenone .

在醋酸、聚乙二醇存在下，铬酸酐和苊在温和的条件下反应，苊可以完全转化为苊酮。

Acenaphthenone was prepared by the oxidation of acenaphthene in the presence of chromic anhydride , acetic acid and polyethylene glycol as a phase transfer catalyst under mild reaction conditions with high yields.

研究了在铬酸酐、冰醋酸和相转移催化剂聚乙二醇存在下苊的氧化反应，较温和的条件可高产率地得到苊酮。

Because glycosidic bonds are part of acetal structures, they undergo acid -catalyzed hydrolysis, that is, cleavage in the presence of aqueous acid and heat.

因为糖苷键是缩醛结构的一部分，他们进行酸水解，也就是说，在酸溶沼和热存在的条件下分解。

It was founded that the renaturation yield was improved in the presence of arginine, thiourea, acetone, acetamide and glycerol compared with no additives.

分析其作用机制异同点；并基于海藻糖和甜菜碱对保护蛋白质的作用，考察了海藻糖和甜菜碱在不同浓度盐酸胍和酶浓度条件下对溶菌酶辅助复性和复性动力学特性，分析了它们作用机理。

The acylation of 2,3-dimethyl-2-butene by acetic anhydride in the presence of H3PO4 was investigated.

在H3PO4存在下进行了2，3-二甲基-2-丁烯与乙酐的酰化反应。

The catalytic esterification of acetic anhydride and nine phenols were investigated in the presence of complex resin catalyst at 20 ℃,and its mechanismes were discussed.

研究了 2 0℃时，醋酸酐与九种酚在复合树脂催化剂下的催化酯化反应，并探索了其反应的机理。

The synthesis of sucrose octaacetate from sucrose with acetic anhydride in the presence of anhydrous sodium acetate is reported.

报道了在无水乙酸钠存在下，蔗糖和乙酸酐反应合成蔗糖八乙酸酯。

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 product poses a chemical risk because of the presence of acetophenone, a substance classified by Directive 67/548/EEC as harmful if swallowed and irritating to eyes.

通报的理由为该拼图垫不符合欧盟指令67/548/EEC ，垫内含有苯乙酮，吞咽对人体有害，对眼睛也有刺激。

In Denmark, a study showed that the root system is the presence of acetylene gas, it is estimated that also inhibit the growth of other species.

在丹麦，有研究表明，其根系有乙炔气体的存在，估计也有抑制其他物种生长的作用。

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。