键距

The valence electron structure of Fe_2B phase was studied on the basis of Yu's empirical electron theory of solids and molecules.The values of valence electrons on every bond in an atomic coordinate cluster were calculated by the method of bond length difference.

根据固体与分子经验电子理论对Fe_2B相的价电子结构进行了定量分析，通过键距差方法计算了Fe_2B晶体配位团各键上的共价电子数。

The ground state energies, atomic charges, bond lengths, bond angles, dipole moments, multipole moments, the molecular orbital compositions and orbital energies have been obtained.

采用RHF法对一卤代苯和卤甲基苯进行了计算，得到了它们的基态能量、原子电荷、键长、键角、偶极距、多极距、分子轨道组成和能级等。

Compared to human oxyHb, the stereochemistry of the haem group region of both the α and β subunits show some difference.

同人oxyHb分子相比，α和β亚基中血红素区域的空间构象发生了一些变化，特别在β亚基，远侧HisE7（63）的咪唑环距血红素平面较远同时绕C〓-C〓键旋转了15°，这使得E7N〓原子同O（2）之间的氢键成为可能。

This implies that the atomic near neighbour distance of metallic bond solid solution is the closet to VCA model among the three solid solutions, although the vegard's law are not followed.

离子键固溶体中第一近邻距随成分的变化量只有近邻距Vegard定律变化量的40％左右，而共价键固溶体只有20％左右，金属键固溶体的变化量最大，一般都在50％以上，甚至高达80％左右。

Metallurgy School, UST Beijing, Beijing 100083, China）ABSTRACT The negative thermal expansion in some complex oxides has beenattributed to transverse thermal motion of A-O-M linkage composed of two-coordinate oxygenbridge bond, and the librationsand tilts of essentially rigid polyhedral blocks in openframework structure. The isotopic NTE materials have been finding moresubstantialapplications in composites and other relative technique fields.

氧化物材料负热膨胀机理邢献然摘要氧化物的负热膨胀性是由于在其开放式的骨架结构中，有二配位的桥氧键产生横向热运动，以及引起的多面体热摆动和耦合作用使非键合M-M1键距变短，导致单胞体积缩小；各向同性NTE氧化物在复合材料及其相关技术领域具有更广泛的应用价值。

According to the empirical electron theory of solid and molecule, the valence electron structure and theoretical cohesive energy of WSi2 were calculated by the BLD method.

根据固体与分子经验电子理论，通过键距差方法，计算了金属间化合物WSi2的价电子结构和理论结合能。

Calculates the coordinates of the spindle and drive shaft and checking the center distance, determined department spindle must use dislodges the gear.

根据柴油机齿轮室盖的结构特点、加工部位、尺寸精度、表面粗糙度及生产率等要求，确定该机床为单工位卧式组合机床；为确保加工精度，采用&一面两销&的定位方案；为实现无级调速，安全可靠，选择液压滑台；根据零件的大小及被加工孔的位置确定主轴箱的轮廓尺寸；由加工工艺选择滚珠轴承主轴，通过计算扭矩确定主轴和传动轴的直径；齿轮的模数是通过类比法确定；齿轮齿数和中间传动轴的位置是由&计算、作图和多次试凑&相结合的办法确定；计算主轴、传动轴的坐标并进行中心距验算，确定部分轴上需采用变位齿轮；轴上的齿轮套、键等零件按轴号选取相应的标准件。

This paper analyze the principle of the joggling in the cold rolling process for involute spline manufacturing and establishes the CAD model of the roller based on the principle of equal pitch helicoids.

本文通过对渐开线花键滚轧时啮合原理的分析，按照等升距螺旋面的形成理论建立了滚轧轮廓形设计模型。

It is found that the melting points of borides of IVB and VB group elements are higher than their simples. It is because their hybridization levels are higher, and their single bond radius are shorter.

发现IVB，VB族元素的硼化物熔点都比相应的单质有较大提高，原因是组成元素的杂阶升高，单键半距随杂阶升高而逐渐下降。

A theoretical study on geometric structure of the Qinghaosu molecule has been Carried out by ab initio method of the Quantum Chemistry.

文章用量子化学从头算法，研究了青蒿素分子的几何结构，结果表明青蒿素分子的构型、键距、键角、二面角C1-O24-O23-C20等参数与X—射线分析测定值十分接近。

Neither the killing of Mr Zarqawi nor any breakthrough on the political front will stop the insurgency and the fratricidal murders in their tracks.

在对危险的南部地区访问时，他斥责什叶派民兵领导人对中央集权的挑衅行为。

In fact,I've got him on the satellite mobile right now.

实际上 我们已接通卫星可视电话了