原子键

The oxidation number of an element in any chemical entity is the charge which would be present on an atom of the element if the electrons in each bond were assigned to the more electronegative atom.

氧化数是指某元素一个原子的电荷数，这种电荷数由假设把每个化学键中的电子指定给电负性更大的原子而求得。

Molecular dynamics simulation was carried out to study transformation pseudoelasticity in NiAl alloy with a initial B2 structure, using EAM type interatomic potential for NiAl.

利用NiAl合金的嵌入原子势，进行了B2结构NiAl单晶中相变伪弹性的分子动力学模拟模拟过程中系统的径向分布函数和键连线原子分布图的变化表明，在外加拉应力的作用下，B2结构的奥氏体向L10结构的马氏体转变，马氏体在长大过程中发生了变体间的转化与合并，不同取向的变体之间由于自协调效应形成共格的孪晶界面。

An ionic bond is characterized by the transfer of an electron from one atom to the other.

离子键的特点是一个电子可以从一个原子转移到另一个原子。

According to the VESs analysis, the intrinsic brittleness of Fe〓Al is due to less lattice electrons, bondcomplex distribution heterogeneity, hydrogen-induced embrittlement, and the difficulty in recovery of the lattice symmetry, while various alloying elements have strengthening and toughening effects through altering the VES parameters.

运用固体与分子经验电子理论建立起Fe〓Al合金各相的价电子结构，在计算中，首次尝试利用TFD模型确定Fe〓Al的原子杂阶，针对不完全有序的B2-Fe〓Al提出"局部平均原子模型"，对Fe〓Al的室温脆性从电子理论上进行了系统的阐述，认为较少的晶格电子、键络分布不均匀、氢致脆性和难以恢复晶体的对称性使Fe〓Al具有本质脆性，合金化元素可以在一定程度上改变价电子结构参数而改善强度和韧性。

Quantitative analysis of the EXAFS spectra showed that, in a 0 1mol/L NaNO 3 solution of pH 7 5, Zn was adsorbed onto the solid surface by sharing the oxygen atom in the hydrous Zn 2+ ions and in the structural unit MnO 6 on the manganite surface.

结果表明，Zn 水锰矿体系中(pH 7 5 ，0 1mol/LNaNO3 介质，2 5℃)，Zn2 +主要是通过共用水合Zn2 +的O原子及水锰矿表面上的O原子形成Zn—O键，从而结合到水锰矿固体表面上的。

The photodissociation study of the molecule CH3ONO not only provides some useful information for an understanding of the bondbreaking processes in polyatomic molecules, but also probes a wide range of dynamic interaction responsible for the dissociation of polyatomic molecules.

CH_3ONO的光解研究不但可以提供一些有用的信息来理解多原子分子的断键过程，还可以探测多原子分子解离的动力学相互作用。

Two special structural features of the sulfonium salt were proved to stabilize its corresponding ylide and depress the 2,3-sigma rearrangement. One is that there is a trimethylsilyl in the end of the allylic double band. This silicon atom can stabilize a α-carbon anion and the corresponding ylide. Another is that there is hydroxy group in the beta-position of sulfonium atom. The oxygen of this hydroxy group may stabilize the sulfonium cation.

为了稳定生成的烯丙基硫叶立德，并抑制它的2， 3-sigma 重排反应，在硫叶立德结构上做了两方面的考虑：一是在烯丙基双键的未端引入硅基，利用硅原子对 a -碳负离子的稳定作用来稳定烯丙基硫叶立德；二是在硫原子的 b -位引入羟基，利用羟基氧对硫正离子的作用来稳定硫叶立德。

The recent advances in the first principles calculations and atomistic simulations further help us in understanding atomic bonding, dislocation configuration and alloying effects in intermetallics which has led to the development of nickel, iron and titanium aluminide alloys with improved mechanical and metallurgical properties for structural use.

第一原理计算和原子结构模拟的新近研究结果能进一步帮助了解金属间化合物的原子结合键性质、位错组态和合金元素的作用。对基本问题的更好了解导致镍、铁和钛的铝化物金属间化合物合金的力学和冶金性能的改进，更接近了结构方面应用的要求。

Next HOMO or HOMO-1 for the radical cations calculated by the ab initio 3-21+G^* method, and the atom-pair interaction energy determined by NMDO calculation, it is shown that when n is equal to or largey than 3 in the bridge chain (CH2)n for bicyclo diamine radical cations, the bridgehead nitrogen atoms form a weak N, N'-three-electron σ-bond through space.

通过比较这些阳离子几何构型，HOMO和NHOMO(即NextHOMO和HOMO-1)，和由MNDO计算确定的原子对作用能，表明当二氮双环游离基阳离子的桥链(CH2)n的n≥3时，桥头氮原子通过空间相互用用形成了一个弱的N，N'-三电子σ键。

It was revealed that the film was constituted mainly by Zr-C, C=C (s^2) and C-C(sp^3) bonds; structure of the films was crystalline ZrCN embedded in an amorphous carbon and carbonitride matrix. With increasing flow rate, film Zr content decreased, but C and N contents increased.

实验结果表明薄膜结构是由ZrCN晶粒镶嵌在无定形碳和碳氮化合物基体中；膜中的化合键主要以Zr-C，C=C(sp^2)和C-C(sp^3)形式存在；随着混合气体流量的增加，薄膜的锆原子分数减小，而N和C的原子分数逐渐增大。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。