The macroporous, strongly acidic, high thermally stable canon exchange resin catalysts were synthesized in the steps of polymerization of styrene and divinylbenzene, purifying copolymer, introducing electron withdrawing group, sulfonation and stabilizing active sites.

Substitution of the aromatic hydrogen atom of the Schiff base ligand with electron withdrawing group decreased the amount of the complex encapsulated in the zeolite cavities, but could improve the catalytic activity of the encapsulated complex.

席夫碱芳环上的H被吸电子基团取代后，降低了Y分子筛超笼中封装的钴配合物的量，但能改善催化活性。

The photodegradation experiment showed that the introduction of electron withdrawing group on methane chain would improve the photo-stability of the dye, while electron donating group would decrease the photo-stability.

三种染料与其母核染料的光降解对比试验说明，甲川链上引入吸电子基团使得染料光稳定性提高，而供电子基团则光稳定性下降。

In chapter 2, we designed and synthesized two novel series of organic dyes by incorporating NC-CH2-COOH as electron withdrawing group at the carbonyl positions of QA skeleton.

在第二章中，我们通过在QA骨架的羰基位置引入吸电子基团NC-CH2-COOH设计并合成了两个系列新颖的有机染料。

We use N-ethyl carbazole as the electron donating group, and the cyanoacetate as the electron-withdrawing group, connecting the two parts together by converting different II bridge bonds.

以n-乙基咔唑作为供电子基团，氰基乙酸为拉电子基团，通过变换不同的∏桥键来合成。

The catalytic system also showed good catalytic activity in the oxidation of other aldehydes. Benzaldehyde derivatives with electron-withdrawing group and aliphatic aldehydes were almost quantitatively converted into their corresponding acids.

应用此催化体系催化其它醛的氧化同样表现出较好的催化活性，有缺电子取代的芳香醛和脂肪醛几乎定量生成相应的羧酸。

By contrast, the exo adduct possesses a trans relationship between the dienophile electron-withdrawing group and the trans diene substituent.

相反，不能进行成环加成反应的反应物有吸电子基团的二烯和二烯烃取代物具有反式结构。

Ester bond as an electron-withdrawing group could undergo as well, so the compound by ester bond connecting occurred more reduction process than ether bond connecting.

由于酯键作为一个吸电子基可以促进还原反应的发生，通过酯键连接的化合物比通过醚键连接的化合物出现更多的还原峰值。

The results showed that dyes with strong electron-withdrawing group, asymmetrical structure and short alkyl chain substituents have better bleaching properties.

结果表明，油溶性染料分子中，取代基团的吸电性强，不对称性大，取代基含脂肪链短的，其漂白性能好。

Poly ( 2,7-carbazole) derivatives, incorporated by electron-withdrawing group in the main chain, form a new low band gap photoactive donor materials.

聚2,7-咔唑材料的衍生物通过与吸电子基团共轭链接能够形成一类新型窄带隙光活性给体材料。

Only when the substrates with strong electron-withdrawing group were failed in this reaction.

只有当底物带有强吸电子基团，反应无法进行。

To investigate the clinical characteristics of the alcoholic liver disease complicated with alcohol withdrawal syndrome, and to analyze whether the severity of alcoholic liver disease influence the performance of alcohol withdrawal syndrome.

探讨酒精性肝病患者中酒精戒断综合征的临床特点，并分析酒精性肝病的严重程度是否影响戒断症状的轻重。

Proposed Policies for withdrawal of Currency from Circulation and Comprehensive Control of Inflation

回笼货币、综合治理通货膨胀的政策建议

The purchasing cost influences the profit and assets payback of the enterprises directly, and also influences the speed of withdrawal from circulation of circulating fund of enterprises.

采购的成本直接影响到企业的利润和资产回报率，影响企业流动资金的回笼速度。

Excess withdrawal over issue

已发行纸币的超额回笼

Objective: To investigate whether withdrawal emergent dyskinesia ( WE D) is the early signal of tardive dyskinesia ( TD).

目的：调查撤药出现的运动障碍（WE－D）是否为迟发性运动障碍（TD）的早期征象。

This paper researched system reliability of Withdrawal Straightening Stands and its construction and function, and built its Failure Tree based on the method of FTA.

本文用故障树分析（FTA）的方法，研究了冶金设备中拉矫机的可靠性，分析其结构和功能，建立了故障树。

The efficiency of mercury withdrawal increases sharply with the increase of porosity and permeability while increases slowly with the increase of the sizes of the pore and throat. The separating of the pore and throat is positively correlated to displacement efficiency, but such correlation is poor.

而随孔喉增大，退汞效率缓慢增加，喉道分选性与驱油效率虽也呈正相关，但相关性较差。

The relationship between efficiency of mercury withdrawal and pore structure parameters was analyzed quantitatively through correlation analysis method; the result indicates that the efficiency of mercury withdrawal is negatively correlated to every pore structure parameter;

在此研究的基础上，利用相关分析法定量分析了储层退汞效率与孔隙结构参数的关系，认为储层退汞效率与各孔隙结构参数之间存在负相关关系；

Negotiable order of withdrawal account

可转让提款指令帐户

Supernegotiable certificate of withdrawal

超级可转让提款命令书帐户