异位

The results also show that subtituent position on the benzene ring has a great influence on the transfer volume. The trends of change of δ〓ΔΦ〓〓 for mand p-isometers with the composition of the mixed solvent are similar. However, the position and amplitude of the limit valve are different from each other. These are discussed according to the inductive effect and the resonance effect.

研究发现：取代基在苯环上的取代位置对迁移偏摩尔体积有明显影响，间、对位取代的异构体在DMF-水混合溶剂中的δ〓Δφ〓〓随混合溶剂的组成变化规律相似，但极值点的位置及幅度有所不同，根据诱导效应和共轭效应对此进行了讨论。

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。

Compared with the MgO prepared by direct thermal decomposition of the MgO precursor, the novel high-specific-surface-area MgO material contains more strong basic sites and less acidic sites and exhibited higher acetone yield and selectivity in isopropanol decomposition, making it a potential solid base catalyst.

与直接焙烧四水乙酸镁制得的MgO相比，这类新型高比表面积MgO具有较多的强碱位和较少的酸性位，并在异丙醇催化分解反应中表现出更高的丙酮收率和选择性，有望成为一类优良的固体碱催化剂。

The structures of the isomers were assigned by using 2D NMR techniques such as gCOSY. Comparing to the eluates from the chromatographic column, the first band contains the m2, the second band contains the ml.

利用一维及二维核磁共振(2D NMR)技术，结合三元胺中吡啶环的磁屏蔽效应，对两个异构体在溶液中的结构进行了解析，对应于Dowex 50Wx 2柱色层分离的第一包带的H离子为n2(cmen的2位胺基与Cl处于邻位)：第二色带的阳离子为ml。

These include catechin and gallocatechin (hydroxyls at positions 5' as well as at 3' and 4' as in catechin), their esters with gallic acid, catechin gallate, and gallocatechin gallate, and their epimers.

它们有几茶素和儿茶素(在5'位上以及如同儿茶素中一样在3'和4'位上羟基化)，它们与酸生成的酯，即儿茶素酸酯和儿茶素酸酯，以及它们的差向异构体。

Possibly the greediest,most selfish beings in the Outer Planes,yugoloths reign supremeamong the evil outsiders of Gehenna.

作为外层位面中最贪婪、最自私的生物，尤哥罗斯魔统治着焦热炼狱位面上绝大多数邪恶的异界生物。

But after 1,2-insertion, the γ-agostic complex can be isomerized to only one β-agostic complex.

能量量低的插入路径是烷基链在N对位是的1，2-插入。2，1-插入路径中的γ-氢桥键烷基配合物能异构化得三个β-氢桥键的烷基配合物，空间位阻最小的最稳定。1，2-插往前只生成一个β-氢桥键烷基配合物。

The coordinated COD of 3 and 4 can be replaced by carbon monoxide to yield the corresponding dicarbonyl species [(C,N-pyN^C-R) M2]BF4 (14, M= Rh; 15, M= Ir). Ligand substitution of 11a by phosphines and azide causes the de-complexation of pyridinyl-nitrogen donor to generate the corresponding carbene rhodium complexes [(C-pyN^C-Mes)RhPR3] (17a, R = Ph, 17b, R = Et) and [RhN3] (19), respectively, indicating the labile nature of steric-hindered pyridinyl-nitrogen donor.

螯合错合物的吡啶配位，可以容易被σ-予体，如卤离子、叠氮阴离子、膦试剂，置换；但是铑与铱金属螫合物与π-酸试剂，如一氧化碳、异腈，则发生COD被置的产物14a与16；与三甲基亚磷酸酯反应时，COD及吡啶均会被取代而得到单芽的三铑-碳烯错合物18；双膦化合物则会取代铑金属上全部的配位基。

Isobutane can be chemisorbed on surface terminal oxygen of Lewis base sites M=O bonds by one or two H atoms in-CH〓.

异丁烷分子以CH〓中C-H键的H端单位或双位吸附于催化剂表面Lewis碱M=O双键的端氧位。

But we don't care about Battlegrounds.

但我们并不在乎沙场中的显露。

Ah! don't mention it, the butcher's shop is a horror.

啊！不用提了。提到肉，真是糟透了。