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The MAX2338includes a low-noise amplifier with an adjustable high-inputthird-order intercept point (IIP3) to minimize intermediation andcross-modulation in the presence of large interfering signals.

它包括一个具有可调的高输入三阶交调点(IIP3)低噪声放大器，用以减少当前大干扰信号下的互调失真和交调失真。

In the presence of Ru, the onset of methanol adsorbate oxidation is shifted to the more negative potentials.

在Ru存在下，甲醇吸附物在Pt电极上氧化的起始电位向负电位移动。

United Airlines is the 18th U.S. Air Force's largest overseas Air Force wing, but not only in the presence of the United States Air Force wing.

第18航空联队是美空军驻海外规模最大的空军联队，而且也是惟一没有在美国本土驻扎的空军联队。

Third, most magnesium alcoholates are prepared by alcoholysis.The process is based on the exchange of alkoxide groups of a metal alcoholate in the presence of an alcohol other than the alcohol corresponding to the original alkoxide,i.e.on the alcoholysis of a metal alkoxide with a different alcohol. Primary alcoholates can be prepared by this process,such as magnesium di-n-propanolate,magnesium di-n-butanolate,magnesium di-isobutanolate.

该方法适用于较高沸点的伯醇的醇镁化合物，例如正丙醇镁、正丁醇镁、异丁醇镁等，但是用醇解法制备出的叔丁醇镁，其纯度只有80％，这是由于叔丁醇具有较大的空间位阻效应，阻碍了醇交换的进一步进行，并且叔丁醇沸点与甲醇相差不大，使得甲醇难以快速蒸出，只能得到一种混合醇盐产物。

Third, most magnesium alcoholates are prepared by alcoholysis.The process is based on the exchange of alkoxide groups of a metal alcoholate in the presence of an alcohol other than the alcohol corresponding to the original alkoxide,i.e.on the alcoho- lysis of a metal alkoxide with a different alcohol. Primary alcoholates can be prepare- d by this process,such as magnesium di-n-propanolate,magnesium di-n-butanolate,m- agnesium di-isobutanolate.

该方法适用于较高沸点的伯醇的醇镁化合物，例如正丙醇镁、正丁醇镁、异丁醇镁等，但是用醇解法制备出的叔丁醇镁，其纯度只有80％，这是由于叔丁醇具有较大的空间位阻效应，阻碍了醇交换的进一步进行，并且叔丁醇沸点与甲醇相差不大，使得甲醇难以快速蒸出，只能得到一种混合醇盐产物。

The catalytic efficiency of 7a was the best when acetone was used as Aldol donor, and the Aldol products were obtained with up to 78% ee in the presence of 10 mol% 7a.

对丙酮与醛的反应，7a的催化效果最好，在10％催化剂存在下产物ee值高达78％。

We found that when acetone was used as solvent, in the presence of TFA, cis-4-pyrrodin-1-yl-L-proline could catalyze the direct asymmetric aldol reaction between acetone and 4-nitrobenzaldehyde with 84% ee.

研究发现，该催化剂以丙酮为溶剂时，加入催化剂等当量的三氟乙酸可以较好的催化丙酮与对硝基苯甲醛之间的直接不对称Aldol反应，得到84%的ee值。

Special attention is paid to the recently found alkane activations in the presence of metal complexes,...read whole description

特别的注意当著金属联合企业被支付到最近发现的链烷活动，读整个描述

The originalprocedure has subsequently been replaced by milder and more environmentallyfriendly conditions. We tried to alkylate 3,4,5-trimethoxytoluene by2-allylphenylbenzyl ether in the presence of N-bromosuccinimide.

本实验是在溴代琥珀酰亚胺的作用下使2-烯丙基苯基苄基醚产生苄正离子，苄正离子亲电进攻3，4，5-三甲氧基甲苯从而进行傅氏烷基化反应的。

The alkylation of benzene with long-chain olefins has been performed in the presence of ionic liquid, the reaction conditions are optimized.

研究了离子液体催化苯与烯烃的烷基化，考察了反应条件对烷基化反应的影响。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。