双晶的

X-ray diffraction is one of the most common and efficient ways to measure a superlattice structure. This dissertation displays the detail results for characterization of Ge〓Si〓/Si superlattices by x-ray diffraction (including x-ray small angle diffraction and double crystal diffraction). It was found, when the growth temperature is lower, the intensities of xray small angle diffraction peaks are modulated by a periodical function, which indicates that both sets of interfaces of the superlattice is highly flat; when the growth temperature is higher, the diffraction peak intensities are simply decay with the increase of diffraction vector, which indicates that one set of interfaces is highly flat but another is not; when the growth temperature is very high, the diffraction peaks are reduced more rapidly, which indicates that both sets of interfaces are not ideal.

本文详细介绍了用X-射线衍射（包括X-射线小角衍射和双晶衍射）方法对Ge〓Si〓/Si超晶格结构特性测试的结果，尤其是发现，当Ge〓Si〓/Si超晶格的生长温度较低时，X-射线小角衍射谱峰的强度随着衍射波矢的增加而周期性调制，表明超晶格的两套界面都十分平整；当生长温度较高时，Ge〓Si〓Si超晶格的X-射线小角衍射谱峰的强度随着衍射波矢呈简单的衰减变化，对应于超晶格内有一套界面不平整的情况；当生长温度进一步提高时，X-射线小角衍射峰明显减少，表明超晶格内两套界面都不理想。

This research was important to understand the symmetry property on Dauphine and Brazil twinning of α-quartz and provided a useful method for the identification of the two kinds of twinning.

这一研究对认清α-石英道芬双晶和巴西双晶腐蚀像的对称关系，鉴定α-石英的双晶类型具有理论与实际意义。

We have fabricated and tested high-T SQUID planar gradiometer patterned from YBCO thin film deposited on a SrTiO3 bicrystal substrate.

我们在10×10平方公厘的SrTiO3双晶基片上，设计并制备了YBCO双晶结dc-SQUID一阶平面式梯度计。

There is a simple orthoclase crystal, a Carlsbad twinned crystal with an intergrowth and right and left Carlsbad twinned crystals.

包括一块简单正长石晶体，一块有交互生长的卡斯巴双晶，以及一块左形的和一块右形的卡斯巴双晶。

On the rhombohedron face {1011}, Dauphine twinning showed different shapes of etching pits between individuals, because rhombohedron positive form {1011} and negative form {0111} appeared on both sides of twin partition line, while Brazil twinning showed symmetry plane between the irregular triangle etching pits of individuals. On the trigonal prism section 11(average20, Dauphine twinning showed different shapes of etching pits between individuals, because trigonal prism positive form {1120} and negative form {2110} appeared on both sides of twin partition line, while Brazil twinning should show symmetry plane between the ellipse or quadrilateral etching pits of individuals, which was not observed.

菱面体{1010}面上存在道芬双晶处，道芬双晶双晶缝合线两端分别是菱面体正形、菱面体负形出露处，导致蚀坑形状不同；菱面体{1011}面上存在巴西双晶处，不规则三角形蚀坑形态的方位关系为对称面关系；三方柱切面{1120}面上存在道芬双晶处，道芬双晶双晶缝合线两端分别是三方柱正形、三方柱负形出露处，导致蚀坑形状不同；三方柱切面{1120}面上存在巴西双晶处，椭圆形或四边形蚀坑方位应为对称面关系，但实验中未见到。

Two types of twin/bicrystal structures with twining planes as (0113) and (2112) have been identified.

我们确认了两种孪晶/双晶结构，它们的孪晶面分别是(0113)和(2112)面。

Due to the effect of twinning, elongation during cold forming of more than 60% is achievable with a tensile strength of more than 590 MPa.

由于生成双晶的影响，在冷成型时，在大于590 MPa的拉伸强度下达到了超过60%的伸长率。

By means of sem, it is found that in the portland cement clinker with high quality, the alite take the shape of trigonalrhombohedron,and belite shows the shape of irregular ovum, also with the parallel and cross twin-crystals.

借助于扫描电子显微镜发现优质硅酸盐水泥熟料中A矿呈复三方偏三角体形貌特征；而 B矿则呈不规则的浑圆状，并且从外层可看到平行双晶和交叉双晶共存。

There exists isomorphous replacement in the rutile structure, and the most prominent feature is the average content of oxides, being 1.22%, 0.39%, 0.35% and 0.22% for V 2O 5, Fe 2O 3, ZnO and CuO respectively. They substitute Ti 4+ in octahedra. The valence of V is 5, and its polyhedron is trigonal bipyramid, which causes the lattice distortion, breaks the raw octahedron symmetry into square bipyramid, and produces the microstrains in the structure.

天然含钒金红石平均含V2O5可达1.22％，Fe2O30.39％，ZnO0.35％，CuO0.22％，这些金属离子可替代八面体中Ti^4 。V以5价形式存在，配位多面体呈三方双锥，其在晶格内部对Ti的替代导致晶格畸变，打破了配位多面体原有的八面体对称而呈四方双锥的几何形态，并产生结构微应力。

PLZT bimorph deflexed to the maxima under irradiation when there was no mechanical load, whereas bimorph did not do work; part of the incident energy was wasted, and the other converted into electrical and mechanical energy and stored in the bi- morph driver.

从材料力学角度推导出双晶片执行器在紫外光照射下产生的最大偏移量和最大驱动力，无机械负载时双晶片在光照下产生最大变形，此时双晶片执行器不对外做功，入射光能一部分损失掉，其余转化成电能和机械能，并存储在双晶片执行器中。

The concept of equivalent rotationally rigidity is offered and the formula of rotationally rigidity is obtained.

主要做了如下几个方面的工作：对伸臂位于顶部的单层框架—筒体模型进行分析，提出了等效转动约束的概念和转动约束刚度的表达式。

Male cats normally do not need aftercare with the exception of the night after the anesthetic.

男猫通常不需要善后除了晚上的麻醉。