对称核

Barley seeds were irradiated with five different doses of 60 Co-γ ray.There were many kinds of chromosome aberration in pollen mother cells,such as bridge,laggards in anaphase I and anaphase II,asymmetrical division in anaphase I and asynchronous division in anaphase II,ring quadrivalent in metaphase I,three pole division and micro-nuclei in telophase I,micro-nuclei in tetrad and some micro-nucleus separates from the tetrad to form polyad.

大麦种子经5种不同剂量γ射线辐照后， M1植株的花粉母细胞出现多种染色体畸变类型，例如后Ⅰ、后Ⅱ中出现桥、落后，后Ⅰ中出现不对称分裂，后Ⅱ中出现不同步分裂，中期Ⅰ出现环状四价体，末期Ⅰ中有三极分裂和微核，四分体中出现微核且有的微核独立于四分体，从而形成多分体。

To solve this problem,the equivalence relation of rough set theory is replaced by an asymmetrical similar relation,and from this relation,an asymmetrical similar matrix is defined,then a new heuristic algorithm with less space complexity that require core and knowledge reduction based on asymmetrical similar matrix is proposed,and an example is given to confirm the validity of the algorithm.

用非对称相似关系代替粗糙集理论中的等价关系，定义了非对称相似差别矩阵，提出了基于非对称相似差别矩阵的高效求核和知识约简算法。该算法无需改变初始不完备信息系统的结构，能直接处理缺省数据。实验结果表明，新算法所获得的决策规则简洁、高效，与缺省值无关。

This theorem states that the sum of the symmetric logic variables constitutes a level-0 kernel of the symmetric logic function.

该定理表明，对称逻辑函数的对称逻辑变量之和恰好构成了该逻辑函数的一个零级核。

Based on the previous work, two expansion formulas of fully symmetric wave function for describing three bosons in different orbits are obtained, which can be used to calculate the nuclear specturm.

在前人已有成果的基础上，给出了三玻色子在不同轨道上时全对称波函数的非对称展开式，这种展开式可直接用于核潜的计算。

In the Infrared spectrum of complexes, there are strong absorptions in ~1 660 cm-1 which can be ascribed to the antisymmetric vibration of the O -C -O unit in heterometallic multinuclear complexes. The different dates of antisymmetric stretching vibration of ox present two modes.

在红外光谱中，杂多核配合物在～800 c~(-1)有强的O—C—O反对称伸缩振动吸收，根据草酸根表现的非对称伸缩振动、对称伸缩振动的数值，判断出它们有两种不同的配位方式。

In this paper, a kernel quantification theory IV is proposed through organical combining kernel function theory and quantification theory IV. The algorithm framework for the new model with large scale-sampling data is established on the basis of Lanczos algorithm which is an iterative method for finding the eigenpairs of a square matrix.

把核函数理论与数量化理论IV模型有机结合，提出了核数量化理论IV模型，并以高阶对称矩阵端部特征对求解的Lanczos算法为基础设计了大样本核数量化理论IV模型的算法框架。

Both were measured using X-ray single crystal diffraction. For the crystal in MeOH, X-ray in compound. In an ansymmetry unit, there are two Cu atoms, two ligands and twosolvent methanol molecules. The tetranuclear complex contains two kinds of Cucenter.

本文在MeOH中得到了阶梯型四核铜骨架配合物；在THF中得到了扭曲的立方烷型四核铜骨架配合物，经晶体结构分析表明，阶梯型四核铜骨架配合物是由两个Cu2被μ~3-剪刀撑二个醇羟基O所连接形成中心对称的二铜二聚体结构。

At the first stage the symmetrized matrix of nuclear cross relaxation rate is obtained from the regularized 2D NOESY peak intensity or symmetrized mixing coefficient matrix.

第一步采用规范化2D NOESY峰强度或对称化混合系数矩阵来计算对称化核交叉弛豫速率矩阵。

Chiral SalanCrX complexesa saturated version of SalenCr(ⅢX are designed,and in conjunction with an ionic quaternary ammonium salt or organic strong base can efficiently catalyze the asymmetric,regio-and stereoselective alternating copolymerization of CO_2 with rac-PO at mild conditions to afford isotactic-enriched polycarbonates with～95%head-to-tail linkages and moderate enantioselectivity.

本论文在Salen构型配体的基础上，设计合成了一系列手性Salan型铬配合物，并将其与季铵盐/有机强碱组成亲电-亲核双组分催化体系，在室温下可以有效的催化CO_2和环氧丙烷的不对称交替共聚反应，实现了CO_2和环氧丙烷的不对称交替共聚反应的区域和立体化学控制，得到95%的头尾连接单元和中等光学纯度(对映体过量值ee%≈70%)的全同结构的聚碳酸酯。

By calculating the neutron skin thickness of nuclei in the range of Z = 8 ~ 120, A = 5Z/3 ~ 3Z ,we find a linear relation between the neutron skin thickness and the isospin asymmetry degree δ:, which is in agreement with the result extracted from the measurements by antiproton annihilation method i.e.:.

我们发现中子皮厚度随对称能系数 a s 以及对称能在饱和密度附近的斜率L、曲率Ksym的增大呈现近似的线性增大的趋势，对称能越硬的核势确定的中子皮越厚。

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