electron-withdrawing group

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。

Some oxygen-containing groups ( mainly carbonyl group) were introduced onto the molecular chains of HDPE through electron beam irradiation, the polarity of HDPE was increased and the compatibility between HDPE and PA6 was thus improved.

通过电子束辐照的方法，在高密度聚乙烯（HDPE）分子链上引入含氧极性基团，增加了HDPE分子的极性，改善了HDPE与PA6的界面相容性。

The 5-year survival rate of the group treated with superficial X-ray or electron beam was 65.1% and 67.8% respectively.

X线与电子线治疗5年生存率分别为65.1%及67.8%（P>0.05）。

It is found that the conjugated plane made up of the amine group and benzene ring is of the active position, and HOMO and LUMO of eight compounds are π-molecular orbital with lone pare electron.

研究表明，这些添加剂胺基和苯环形成的共轭平面构成了活性部位，其HOMO和LUMO均为π-分子轨道。

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。

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。

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。

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。

Light and electron microscopic examination might reveal slight alteration of germ cells and Leydig cells only in the group of 260 mg/ kg.

病理组织学检查仅在260mg／kg组光镜下可见曲细精管内细胞层次减少，电镜下可见生精细胞线粒体轻度肿胀，支持细胞溶酶体增多。

The space effect of the two CH_3 group makesDCEDMA forming a quasi-reversible single electron process.

甲基的空间效应使DCEDMA形成准可逆的单电子过程。

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。