查询词典 benzene ring

The result shows that both of the two C-C double bond are exist as a trans configuration. The dihedral angle between benzene ring was 24.6°and 37.5°respectively.

发现均二苯乙烯荧光团的两个双键都是以反式结构存在，并且分子中的苯环并非完全共平面，相邻苯环之间的夹角分别为24.6°和37.5°。

Aniline compounds containing heptafluoroisopropyl was synthesized through taking sodium dithionite as evocating agent, and introducing heptafluoroisopropyl by free radical electrophilic substitution on benzene ring.

以连二亚硫酸钠为引发剂，在苯环上通过自由基亲电取代反应引入七氟异丙基，合成了一系列含七氟异丙基的苯胺类衍生物，研究了各种条件对反应的速度和收率的影响。

In recent years, more and more scientists modify the double bond or benzene ring of resveratrol to get higher active, lower toxicity derivates.

近年来越来越多的科学家对其进行结构改造以得到高活性化合物，例如对双键、苯环的修饰。

The yields were better when DHPCE with nitro group in meta or ortho position of the benzene ring were hydrolyzed in basic conditions, while the hydrogenolysis and acidic reactions gave very poor yields.

当苯环的间位和对位存在硝基，碱性水解时，在二氢吡啶环的3位引入氯乙醇的酯能得到较好的收率；酸性水解和氢解法则不宜用来合成ADHPA。

It also can be used as the controlling indicators for membrane bio-fouling in the prophase. When the bio-fouling membrane was anatomized, it shows that the bio-fouling membrane are meshy and coupling, whose primary ingredients are organics matter such as albumin, benzene ring, hydroxyl acid, fatty acid and so on, as well as microorganisms such as cocci, bacilli, leaf mold, alga and so on.

微生物污染解剖试验分析表明，严重的微生物污染薄膜成网状粘联结构，分析到的主要成分有白蛋白、苯环类、脂肪酸和芳香烃类等有机物，可观察到的微生物有球菌、杆菌、霉菌和藻类。

Two classes of specific binding sites in the polymer matrix were investigated by Scatchard analysis, which indicated that two kinds of complexes between functional monomers and templates were formed before the polymerization process. Comparing with the structure of TNT and acrylamide, one kind of complex between TNT and acrylamide was strongly charge-transfer complexing interaction by p-πcomplex between electron-rich amino group of acrylamide and electron-deficiecy-benzene ring of TNT, the other was hydrogen bonding interaction between amino group (-NH_2) of acrylamide molecule nitro group (-NO_2) of TNT.

Scatchard分析结果表明，在TNT印记聚合物微球中存在两类结合位点，这表明在聚合反应之前，TNT与功能单体丙烯酰胺分子之间存在两种不同类型的作用力而自组装成两类的模板分子-功能单体复合物，一类可能是由于富电子的丙烯酰胺和缺电子的TNT的苯环通过p-π配键而形成的电荷转移复合物，另一类可能是由于丙烯酰胺的胺基与TNT的硝基之间的氢键作用而形成的复合物。

We described that the nitro group is a stronger electron withdrawing and meta activating characters than the imide group, the amino and hydroxy are both electron donating groups and had ortho, para activating characters. The methyl group might have a steric hindrance effect in this reaction. Our results indicated that methyl group at the ortho position of the amino group on the benzene ring, the steric hindrance effect became stronger.

另一方面，由产率上的结果来看，可以得知硝基为强力的拉电子基团，会减少邻位和对位胺基的电子密度比间位多；而氢氧基与胺基是供电子基团，会增加邻位和对位胺基的电子密度比间位多；甲基取代对反应则只有立体障碍的影响，而且与反应的氨基成邻位存在下影响最大。

The four fluorescence peaks are generated separately by the combined actions of the methyl parathion and the acetone. In methyl parathion molecule, there are the transition of n electrons in nitryl, the transition of π electronic structure formed by the oxygen atom and the benzene ring and the transition of n electrons in P=O group. In acetone molecule, there is the transition of n electrons in C=O group.

分析得到，四处荧光峰分别是溶剂丙酮分子中C=O上的n电子跃迁、硝基上的n电子跃迁、甲基对硫磷分子中氧原子与苯环形成的大共轭π电子结构跃迁以及P=S上的n电子跃迁共同作用产生。

A process for reducing nitryl with unstable guanyl on para-position of benzene ring into azyl features that active metal reacts on organic acid and solvent at ordinary temp. and pressure to reduce N-(2 or 3-M, 5 or 6-M',4-nitrophenyl)-N',N'-dimethyl acetamidine into N-(2 or 3-m, 5 or 6-M', 4-aminophenyl)-N',N'-dimethyl acetamidine, where M=H,-R,-OR,-COOR (R=H, C1-C6); and M'=H,-R,-OR,-COOR (R=H, C1-C6). Its advantages include reduced by-reaction and high reducting rate up to 80%-95%.

本发明是将苯环上对位带有不稳定脒基的硝基还原为氨基的方法，采用活泼金属，如：锌或锡，与有机酸和适当的溶剂，在常温、常压下发生反应，将N－（2或3－M，5或6－M＇，4－硝基苯基）－N＇，N＇－二甲基乙脒还原为N－（2或3－M，5或6－M＇，4－氨基苯基）－N＇，N＇－二甲基乙脒，其中M＝H，－R，－OR，－COOR（R＝H，C1－C6），M＇＝H，－R，－OR，－COOR（R＝H，C1－C6），减少了副反应，使还原收率达到80％以上，最高可达95％以上，更适用于工业化生产。

Syntheses of PPVs derivatives with alkoxyl as side-chain by the method of dehalogenating condensation reaction Those PPV derivatives, named poly (2-methoxy-5-alkoxyl) phenylene vinylene,containing alkoxyl on benzene ring, were placed on emphasis in this paper.

一。通过强碱诱导的去卤缩合法合成支链含不同烷氧基的PPV衍生物本文首先重点研究了支链中含不同链长烷氧取代基的PPV衍生物：聚(2-甲氧基-5-烷氧基)对苯乙炔。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。