共价键

If the optical electronegativity Dwglass is high, the materials are considered ionic in nature and if its magnitude is less, the materials are considered to be covalent in nature.

如果光 电DW的玻璃是高，材料被认为是离子的性质，如果其规模较小，材料被认为是共价键的性质。

The interaction of DAB and RB with SPM and the cells are exothermal and idiopathic, which contained the union of non-covalent bonds, such as electrostatic bond, hydrogen bond and van der Waals force. Moreover, most of DAB and RB were accumulated on the excellular membrane and walls, to hardly enter the cytoplasm.

结果表明， DAB， RB与SPM和细胞外膜有强烈的单分子层化学吸附，是自发的放热反应，主要通过电荷对吸引、氢键等非共价键结合在SPM和细胞外表面，且绝大部分DAB， RB积累、滞留在细胞膜壁上。

Gold nanoparticles was self-assembled onto a platinum electrode to form a negatively charged surface, and cationic dye-thionine was linked by Au—S and Au—N covalent bond and electrostatic adsorption as an electron transfer mediator.

在铂电极上自组装一层纳米金，构建负电荷的界面，然后通过金-硫、金-氮共价键合作用和静电吸附作用自组装一层阳离子电子媒介体硫堇。

May be an electrovalent bond , covalent bond and metallic bond mark like chemistry key.

化学键一般可分为离子键、共价键和金属键。

Reactive dye not only can covalently bind with modified flax by nucleophilic reaction, but also can form electrovalent bond. Attracting among hydronium is of benefit to nucleophilic reaction.

改性亚麻与活性染料之间即可发生亲核取代反应形成共价键结合，又可形成离子间的库仑力，而且离子间的相互吸引更有利于染料上的活性基与纤维素发生亲核取代反应。

Understand the basic conceptions on homolysis and heterolysis of covalent bonds, and on the nucleophilic substitution and elimination; Grasp the mechanism and stereochemistry of S N 1 and S N 2 reactions; be capable of judging the stability of carbocations; know the factors that can influence the rates of S N 1 and S N 2 reactions; grasp the elimination reactions of haloalkanes, the mechanism and stereochemistry of E1 and E2 reactions.

了解共价键的均裂和异裂及亲核取代反应的基本概念；掌握 S N 1 和 S N 2 反应机理和立体化学；能够判断正碳离子的稳定性；了解影响 S N 1 和 S N 2 反应速率的因素；掌握卤代烷消除反应， E1 和 E2 反应机理和立体化学。

The C atom in ideal graphite crystals is hybridized in sp^2 orbital and forms covalent bonds with adjacent 3 other C atoms. The graphite crystals consist of stacks of parallel hexagonal net planar layers. These layers are integrated with Van der Waals attraction.

理想的石墨晶体是由碳原子以sp^2杂化轨道和邻近的三个碳原子形成共价键，构成六角平面的网状层片结构，层片之间以Van der Waals力相结合。

Kaner, UCLA professor of inorganic chemistry and materials science and engineering.

他认为，金刚石之所以是世界上最硬的材料，是因为金刚石的碳原子间具有极短的共价键。

The chemical bonding is formed the between coating and the substrate. The bond shows a mixed property of covalent bond and ionic bond.

镍晶格和基体粒子之间产生了键合作用，形成的键显示出共价键和离子键的混合性质。

Usually, they are suitable to mixed crystals with metallic bond but not to those with covalent bond or ionic bond.

上述近似方法通常适用于金属键混晶系统，但对于共价键或离子键混晶系统计算结果则不理想。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。