对称的

The structures and stabilities of the ground-states for Cu13-nAgn clusters have been studied by Gupta model potential based on tight binding second moment approximation in combination with a genetic algorithm. It is found that the lowest energy structures of the pure clusters (n=0,13) are perfect icosahedron, and the structures for the bimetallic clusters (n=1～10) have stable structure which are slightly deformed with respect to the perfect icosahedron, The Cu atom prefers to occupy the center of the clusters with higher coordination numbers.

在混合团簇基态结构优化的遗传算法方案中增加了交换算子，结合Gupta紧束缚模型势研究了Cu13-nAgn团簇的最低能量结构，选择合适的交换和杂交概率，可有效地提高优化效率，优化结果表明，Cu13和Ag13是全对称的二十面体，n=1～10的混合团簇能形成稳定结构，其构型是在二十面体基础上发生畸变，Cu原子趋于处在团簇中心，随着Ag原子数目的增加，原子间的平均距离单调增加，团簇的结合能单调减小，Cu2Ag12和CuAg12只存在亚稳结构。

Simultaneously, when the volume fractions of coexisting three-liquid-phases are converted into mass densities, it is also found that the coexisting curve of temperatures versus mass densities of phases is also standard inverse "S" type curve.

实验结果表明，在平衡共存三液相中，水、环己烷和二乙二醇丁醚的体积分数随温度改变的变化曲线分别是倒"S"型，正"S"型，"结"型；将共存三液相的体积分数转化为对应的相密度后，相密度随温度改变的变化曲线也是规整的倒"S"型；而且，3条"S"曲线形状均表现出不对称的特性。

The asymmetrical radiation of heat remains a prime suspect, as presented at the second ISSI meeting in Berne, Feb 2007. A presentation at the APS April 2008 meeting suggests that differential heating may account for as much of 1/3 rd of the observed acceleration.

2007年2月在伯尔尼举行的第二届ISSI会议上，人们仍然认为非对称的热辐射是最主要的嫌疑。2008年4月的APS会议上，一个报告指出这种热辐射的方向差异可能产生观测到的1/3强的加速度。

In the process of investigation on the torsional effect of quartz crystal, mirror symmetric conservative law is applied to ascertain the connection between the physical characteristics of leftwards spiral crystals and rightwards spiral crystals.

面对工程界对左旋石英晶体压电性质的描述不统一的现状，从晶体螺旋对称的本质出发，应用宇称不变性明确地建立了左、右旋晶体这两种客观实在物质的物理性质之间的联系，给出了建立这种联系的方法，并应用到了左旋石英晶体的三阶压电张量和四阶弹性张量的确定中。

Fenton has given particular attention to the treatment of singularities in the governing integral equation involving the symmetric Green's function — a feature apparently not accounted for by Black — and he reduces the relevant line integral equations to forms possessing series which are rapidly convergent.

Fenton 已经把特别的注意给奇异的治疗在那统治包括对称的格林的功能的整体的相等-一个特征显然地不根据黑色解释-而且他让有关的线整体相等变成持有快速趋集于一点的系列的表格。

The results show that the ground state structures of CB(superscript -)(n=1~6) clusters are linear as C clusters due to their isoelectrons. For CB (n=1~6) clusters, the ground state structure of C2B is asymmetric triangle and C6B is C(subscript 2v) symmetry planar monocycle, while the other clusters are linear.

结果表明CB(n=1~6)团簇的基态构型均为线形，这与等电子的C簇合物的结构是一致的；CB(n=1~6)团簇的基态构型中，除C2B为不对称的三角形，C6B为具有C(下标 2v)对称性的环状结构外，其余均为线形结构。

The main conclusions from the works presented in this thesis can be as this: for the Galactic OH 1612MHz masers, the radiative pumping mechanism coexists with other mechanisms while some other unresolved problems need to be solved after the launch of more advanced space infrared spectrometer and the more reliable identification of the evolutionary status of the maser bearing infrared sources;the asymmetrical 53.3μm absorption line profile could become a powerful tool to assist us to observationally discriminate the radiative pumping mechanism from other pumping mechanisms in the OH masers.This is the English version of my PhD thesis.

通过本论文的研究工作，我们可以得到这样的结论：在银河系内的OH 1612MHz脉泽中，辐射抽运机制与其它抽运机制并存，而还有一些未解决的问题需要等待更先进的空间红外光谱观测设备的使用并与天体类型证认工作相配合加以解决；不对称的53.3微米吸收线轮廓特征有可能成为帮助我们从观测上对OH脉泽的辐射抽运机制加以鉴别的有力工具。

According to the plane cross section assumption, configuration of a rod is expressed as a history of the cross section with arc coordinate. A special solution which stands for equilibrium in straight line state is obtained from differential equilibrium equation. Linear perturbation equation is derived and its general solution is obtained in which the integral constants are determined by constrained conditions at two ends of the rod. The condition of existence of non zero solution of the integral constants gives to the Greenhill formula of exact elastic rod model, which shows that the boundary of stable area is a closed curve and of symmetry, and inference of shearable and extensible to stability of the rod is depend on three factors: difference between flexibility of shear and extension of a section of the rod, bending stiffness and the length of the rod.

基于平面截面假定，弹性杆的位形表达为截面的弧坐标历程，根据平衡微分方程得到了两端受力螺旋作用时的直线平衡特解，导出了线性化扰动方程及其通解，积分常数根据两端铰支时的边界条件确定，并根据其存在非零解的条件得到弹性直杆精确模型的Greenhill公式，表明稳定域为一对称的封闭区域，拉/压和剪切对稳定性的影响取决于：拉/压柔度与剪切柔度之差，抗弯刚度和杆长这三个因素

Using two symmetrical plano-convex lens system to fabricate grating was analyzed and the characteristic of diffraction wavefront aberration of the grating was summarized by ray tracing program using MATLAB siftware.

分析使用两个对称的单平凸透镜光路制作光栅并用MATLAB编写光线追迹程序分析了所制作的光栅的衍射波像差的特点，经计算得出在较小焦比D/F情况下其衍射波像差仅与两支光路点光源的调节偏差之差有关与单独的各个偏差无关；初级像差中球差很小几乎可忽略：彗差仅与垂轴调节偏差之差成线性关系；像散仅与轴向调节偏差之差成正比；且当平凸透镜的焦比D/F增大时，各像差项迅速增大。

It is on the basis of an analysis of the financing behavior that the author draw a conclusion: the optimal financing strategy is determinedby the tangency point of quantity indifference curve of financing and cost indifference curve of financing, furthermore which means to equal to for random two kinds of the marginal financing cost of financing product.

我国证券市场供求的统计范围应该主要界定为证券的一级市场，供给的统计口径应按照新的融资方式分类标难来确定。在对我国证券市场1987—1999年的实际总供求按新的口径范围计算和分析后表明：我国证券市场的平衡是一种管制性的动态平衡，在供给机制与需求机制不对称的同时，需求大于供给。

As she looked at Warrington's manly face, and dark, melancholy eyes, she had settled in her mind that he must have been the victim of an unhappy attachment.

每逢看到沃林顿那刚毅的脸，那乌黑、忧郁的眼睛，她便会相信，他一定作过不幸的爱情的受害者。

Maybe they'll disappear into a pothole.

也许他们将在壶穴里消失