价电子

This is a chemical bond that results from the sharing of valence electrons between atoms.

这是一种共用原子间的价电子而形成的化学键。

The valence electron structure of medium chrome cast iron matrix is set up and the effect of Si on medium-temperature phase transformation is analyzed by using empirical electron theory of solids and molecules.

此文建立了290Cr8Si2中铬铸铁基体的价电子结构，运用固体与分子经验电子理论分析了中铬铸铁中Si对铸铁中温相变的影响，分析和实验结果表明，290Cr8Si2中铬铸铁基体含C、Cr、Si的-γFe晶胞中，C原子与Si原子的结合力强于C原子与Cr原子的结合力，中铬铸铁中较高的含Si量降低了铸铁基体的含Cr量，进而降低了中铬铸铁的淬透性。

The ground state of Ag atom has a closed Ad shell and a single s valence electron, hence it could be seen as "alkali-like" metals.

基态银原子具有饱和的内层d电子4d~(10和1个价电子(5s~1)的电子构型，与碱金属壳层结构类似，因此被看作"类碱"金属。

It utilizes its four valence electrons completely in the establishment of four covalence , its valence shell becomes saturated.

碳原子能够利用其全部四个价电子构成共价键，并形成稳定的饱和价电子层。

The ability of carbon to form stable compounds in such astonishing numbers arises in that it utilizes its four valence electrons completely in the establishment of four covalence,its valence shell becomes saturated.

碳原子能够利用其全部四个价电子构成共价键，并形成稳定的饱和价电子层。这就导致碳元素能构成各类数目惊人的稳定化合物。注意本句使用的是"逆序"的翻译方法。

Nearest M—C bond. Comparing the covalent electron density of MC with NiAl at different crystal planes, it is found that the electron density along the interface (110)_//(100)_ ...

通过对NiAl和MC的不同晶面的共价电子密度的分析发现：(110 ) NiAl和(10 0 ) MC在一级近似范围内基本上保持连续；采取适当的制备工艺，使复合材料中存在尽可能多的(110 ) NiAl//(10 0 ) MC，有可能使这种复合材料具有更优异的力学性能

Based on the average lattice and average atom models, effects of interstitial impurities on the valence electron structures and phase transformation of Ti-Al alloys are analyzed, and the degree of descension of bond energy, melting point and liquidus temperatures as affected by interstitial impurities are calculated by the bond energy formula of the EET.

应用固体与分子经验电子理论的平均晶胞和平均原子模型分析计算了间隙杂质对Ti-Al合金价电子结构和相变的影响。同时根据该理论的键能公式计算了间隙杂质影响下的键能、熔点和液相线的变化。

In the single crystal of C60 with a FCC structure,positron mainly appears outside the C60 molecule.The main annihilation space is the interspace between molecules.The calculated positron bulk lifetime in C60 is 352ps, which agrees with experiment value of 356ps in literature.In carbon nanotube bundles with different dimeters,as the diameter of carbon nanotubes increases,the main space where positron appears changes from the interspace of carbon tubes to the space inside carbon tubes,the radio between positron annihilation with valence eletrons and core eletrons becomes larger,the positron bulk lifetime in carbon nanotube increase rapidly first and come to be a constant at the end.The calculated positron lifetime of carbon nanotube with a dimeter of 0.8～1.6ns is 332～470ps,which agrees with the experiment value of 394ps.Positron annihilation has been studied in widly used compound semiconductors.

计算结果表明：在片层结构的石墨晶体中，正电子主要在石墨层间的空隙中湮没，计算出的石墨中的正电子寿命为208 pS，与文献中的实验结果215 ps符合很好；在金刚石单晶中，正电子主要在碳原子之间的空隙中存在并发生湮没，计算出的金刚石中的正电子寿命为115 ps，文献中的实验结果110 ps左右符合；在面心立方结构的C60晶体中，正电子主要在C60分子球壳内外侧及分子之间存在，C60球形分子中心正电子分布很少，正电子的湮没区域集中在C60分子之间的空隙区域，计算出的C60中的正电子寿命为352 ps与文献中的实验结果356ps相符合；对于不同管径碳米管束中的正电子分布，随着碳纳米管直径的增加，碳纳米管束中的正电子由主要在碳纳米管管间的区域出现转变为主要在碳纳米管管内中心的区域出现：碳纳米管束中的正电子与碳原子的价电子的湮没概率变得越来越大，与核心电子的湮没概率变得越来越小；碳纳米管束中正电子的湮没寿命先迅速增大，而后趋于一定值。

The doublet nature of this and other lines in the Na spectrum indicates a doubling of the expected number of states available to the valence electron.

钠光谱中的这条线以及其它线的双重性指出预期价电子可用的状态数是双重的。

The bonding parameter topologcal index of valence electron energy level is defined as Es=(1+qi).

价电子能级键参数拓扑指数被定义为：Es=(1+qi)。

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。