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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。

Adsorption and desorption of acetylene on HZSM-5 and NaZSM-5 zeolites were investigated in the presence of trace water.

在80℃下，NaZSM-5上乙炔的饱和吸附量约为HZSM-5上的5倍。

The energy of excited state depended on the nature of different cations. 3. 4-(4-tolyl)-6-phenyl-2, 2'-bipyridine platinum acetylide complex containing a monoazazcrown moiety in the acetylide ligand could signal Mg〓 specifically and displayed large changes both in color and in luminescence intensity upon complexation with Mg〓. The most striking result was that it could signal Mg〓 specifically even in the presence of alkali and alkaline earth metal ions in high concentrations.

对位带有氮杂-15-冠-5冠醚的苯乙炔为辅助配体的4-（4-甲基苯基）-6-苯基-2，2'-联吡啶Pt络合物AC，不仅在碱金属和碱土金属的存在下吸收光谱明显改变，更有意义的是，它只有在Mg〓离子存在时能够发光，因此可以通过发射光谱选择性的识别Mg〓，尤其可以在高浓度的其它金属离子存在下选择性的检出Mg〓离子。

You can snipe the second and third union leaders from this position.

您可以鹬第二和第三工会领袖从这一立场出发。

Aiming at the currently shortage of XML streams quality detecting, this paper proposes a new forecasting method of XML streams quality by least squares support vector machines, which is used the method of XML keys' vector matrix as windows, and vector product wavelet transform to multilevel decompose and refactor the XML streams series, that can fulfill real-time checking demand of XML quality, and ensure constraint, consist- ency and integrality. For even more adapting net load, it proposes a control strategy by weight and adaptive adjustment to ensure XML streams quality.

针对当前XML数据流质量检测存在的不足，提出构建XML键的矢量矩阵作为窗口，利用矢量积小波变换多级分解与重构XML数据流，再结合最小二乘支持向量机对XML数据流质量进行预测的一种方法，满足XML数据流质量重构时实时检测的要求，保证XML数据的约束性、一致性与完整性；为了更好的适应网络负载，采取加权与自适应窗口调整等调度策略充分保证XML数据流的质量检测。