取代物

The direct electroreduction of nitrite requires large overpotential on most electrode surfaces, however, various transition-metal complexes were proved to be good catalysts for nitrite reduction.

NO〓〓的直接电还原需要很高的过电位，但各种各样的金属配合物被证明是NO〓〓电还原的良好催化剂，而我们在实验中惊奇地发现一系列饱和未取代的和稀土取代的杂多化合物对NO〓〓还原产生良好的催化作用。

D2 hydantoinase (EC3151212) can change the D type racemates of the racemic D,L252 monosubstituted hydantoin to D2N2 carbamoylase, and the leftover L252 monosubstituted hydantoin due to never reacted with D2 hydantoinase, shown as figure 1, firstly racemizing, thus makes the D,L2 hydantoin completely changes to pure optical D2N2 carbamoylase, and then be changed to D2 amino acid.

海因酶具有底物特异性，D2海因酶(EC 3151212)可转化外消旋的D ，L252单取代海因中的D型消旋体成为D2N2氨甲酰氨基酸，剩余的L252单取代海因由于完全不被 D2海因酶所作用，如图 1所示，先进行消旋，从而使得 D ，L2海因完全转化为光学纯的 D2N2氨甲酰氨基酸，并进一步被转化为D2氨基酸。

The 7-bromo group was replaced with various aniline, and then treated with 4-methoxybenzenesulfonyl chloride to afford the 6-azaindole-1-sulfonamides.The synthesis of 7-aryl-6- azaindole-1- sulfonamide derivatives were prepared by a Suzuki reaction at 7-position, utilizing the 7-bromo-6-azaindole was treated with a variety of phenylboric acid to give the designed 7-aryl substituted 6-azaindoles.

将七号位碳上的溴基取代成各种苯胺类衍生物，再与4-甲氧基-磺基氯苯反应得到6-氮基吲哚-1-磺胺。7-苯基-6-氮基吲哚-1-磺胺类衍生物的合成是以7-溴基-6氮基吲哚-1-磺胺为起始物和各种苯硼酸经由铃木偶合反应在第七号位碳上，得到在第七号位碳上有苯基取代的6-氮基吲哚-1-磺胺。

However, three isomers are obtained when [3(5)-〓-5(3)-MeS]pyrazole or[3(5)--5(3)-MeS]pyrazole reacts with 〓 in the same conditionpossibly owing to the influence of both the steric and electronic factors.

通过配体与〓的光化学反应，首次分离得到了不对称取代的双吡唑烷VIB金属配合物，但3位取代基的立体位阻减弱了双吡唑烷与〓的反应。

In comparison with 〓ligand the substitution of one phenyl groupby pyridyl ligand renders this cluster a self defocusing effect different with previousbutterfly shaped clusters, so the peripheral ligands may also play an important role onthe NLO effects.

配体中的吡啶取代基取代苯基的微小改变使标题化合物具有了不同于以往蝴蝶状簇合物的非线性折射性质，即表现为自散焦，从而说明外围配体对非线性也具有大的影响作用。

Public policy implementation of the non-specific in common: public power for unpublic use, or alienat ion of public power, no longer subject to the public interest, the replacement of public interest objectives, replace the private interests of the public interest, the public interest as a small number of people community of interests posed by the unique structures of monopoly and efficiency to replace the fair, such as the imbalance between the supply of public goods.

公共政策执行的非公共性的具体表现在：公共权力的非公共运用，即公共权力被异化，不再服从公众的利益，公共利益目标的置换，即私人利益取代公共利益，公共利益成为少数人构成的利益共同体所垄断的特有物，效率取代公平，公共物品供给失衡等。

The maleic and o - phthalic anhydrides and CH3COOC2H5 only lead to partly chlorinesubstituted polysilanes.

而顺丁烯二酸酐、邻苯二甲酸酐和乙酸乙酯则只进行不完全的Cl取代，根据分子活性的不同得到取代比率各不相同的共聚物。

This provides a convenient method for the selective oxidation of alcohols to aldehydes and ketones.

带给电子取代基和吡啶取代基的底物能顺利被氧化。

The calculated results indicated that the HOMO and LUMO of the 2, 7-linked and 3, 6-linked carbazole trimers are both slightly destabilized on going from methyl substitution to sec-butyl substitution.

计算结果表明：2，7-和3，6-咔唑三聚物的HOMO和LUMO由甲基取代到仲丁基取代逐渐变的不稳定。

The ee's of30-93% and yields of 64-96% were achieved in NaClO / 4-PPNO and m-CPBA /NMO oxidant systems by using substituted styrenes and substituted2,2-dimethylchromenes as substrates.

在优化反应条件下，在NaClO／4-PPNO、m-CPBA／NMO两个氧化体系中，对取代苯乙烯系列底物获得了30～70％ee和64～96％的收率；对取代苯并吡喃类化合物，获得了84～93％ee和82～96％的收率。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。