对称

The studies and analyses about the formation and the biggest possible span of the symmetry and unsymmetry stick 〓 been made. And from the study results, the calculating formulas of the outlet magnitudes have been given out.

论文较全面地分析研究了对称粘结拱和非对称拱粘结的形成形式及可能产生的最大稳定拱跨，并由此给出了防止产生稳定粘结拱所需的出矿口计算式。

A coding scheme is proposed to eliminate the redundancy of output vectors in pyramidal lattice vector quantization .

并证明了，存在唯一的滤波长度为5的对称双正交小波，不存在滤波长度为5的反对称双正交小波。

Keywords: ARCs;Circular cavities;SRS;Raman modes of weak gain;Limit of detection of trace elements

中文关键词：非圆对称及圆对称微型谐振腔；受激拉曼散射；弱增益拉曼模式；痕量元素分析极限

Owing to the geometrical symmetry of microdisk cavities, they support whispering gallery modes in which light circulates around the periphery of the structure and is confined by total internal reflections at both the sidewall and the top and bottom surfaces of the MD.

在微碟共振腔圆柱对称的结构中，电磁场藉由在碟缘墙面上全反射环绕而形成共振，产生所谓的WGM模态，透过湿式蚀刻，让微碟上下表面暴露於空气中，使相对折射率差异大，因而场型更能够对称地被局限在微碟共振腔内。

Based on the structure of Wollaston prism, a new design of symmetric beam splitting prism is given. From reforming the end surface of o light, we can get symmetric beam splitting.

基于Wollaston棱镜的结构，给出了对称分束偏光棱镜的一种新的设计，即通过修正 o 光束的出射端面来实现对称分束。

Based on the structure of Wollaston prism, a new design of symmetric beam splitting prism is given. From reforming the emergent end surface, we can get symmetric beam splitting.

基于Wollaston棱镜的结构，给出了对称分束偏光棱镜的一种新的设计，即通过修正光束的出射端面来实现对称分束。

Started from D-tyrosine, we obtained the tetramic acid 96 using Jouin reaction. The assembly of the second fragment 109 was stared from 1,4-butandiol,using asymmetric alkylation reaction developed by Oppolzer as a key step. Coupling of the tetramic acid 96 with 109 provided the key intermediate 110 according to Yoshii\'s procedure. After remove protective group and Sharpless epoxidation, we obtained the key intermediate 113. Its macrocyclization to form the final product is in progress.

本论文的第二章主要对Macrocidin A开展了合成工作，我们从D构型的酪氨酸出发，经过官能团转换；利用Jouin反应生成Tetramic acid 96，另外一个片断从1，4-丁二醇开始经过多步反应生成碘化物104，利用Oppolzer发展的手性樟脑磺酰胺为辅基参与的不对称烷基化反应，引入手性甲基，生成关键中间体109，接着通过Yoshii发展的方法连接96和109生成110，经过Sharpless不对称环氧化反应建立环氧化合物，然后脱去保护基得到关环前体113，分子内的Mitsunobu反应进行关大环反应正在进行之中。

This dissertation concentrates on the application of symmetry in the design of Dammann gratings for controlling of the zero order's intensity and higher order's intensities.

本论文将镜像对称结构引入达曼光栅，设计出反转对称型达曼光栅，并对多值位相达曼光栅进行了理论设计，其主要内容如下： 1。

A configuration that transition points are reflection symmetric about the midpoint with phase offset in one period is proposed. The intensity of the zero order becomes the function of the phases and can be eliminated.

采用周期内位相突变点镜向对称，前后半周期位相相差结构设计的反对称型达曼光栅，可使其零级衍射光斑强度仅是位相的函数，因此可消除零级谱点。

Botany Having differing floral parts, as of a zygomorphic or asymmetrical flower.

不规则的：花的组成部分相异的，如两侧对称或不对称的花

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。