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The highest ee value of 71% was achieved by using chiral molybdenum 2'-pyridingyl alcoholate complex at 0 ℃. After addition of phase transfer catalyst Bu4NBr, the yield and ee value were remarkably increased.

其中手性吡啶醇二氧合钼在0℃下的对映选择性ee值达到71%；加入相转移催化剂四正丁基溴化铵，催化剂的活性和对映选择性有显著提高，其中手性吡啶醇二氧合钨在50℃下ee值由54％提高到78%。

Its zinc complex was applied in asymmetric direct aldol reaction of acetone and p-nitrobenzal...

设计合成了一种NOBIN衍生的手性配体，初步研究了该手性配体的双核锌配合物在对硝基苯甲醛和丙酮的不对称直接醇醛缩合反应中的催化应用，20℃和20mol％催化剂量下，获得了32.5％ee和72％收率的产物。

Since July, missile testing has been halted in Syria after a surface-to-surface missile exploded at a military complex near the northern City of Aleppo during a joint ...

今年七月以来，导弹试验已经停止在叙利亚后，地对地飞弹爆炸，在一个复杂的军事附近的北部城市阿勒颇在一项联合

Deficiency of selenium in chicken decreases immunity of erythrocyte and the regulation of erythrocyte to the specific immunity, which includes the decrease of the phagocytic ability of phagocyte, the eliminating ability of circulatory immune complex, the ability of identifying organism, carrying antigen and the immune regulation effects in the activation course of T lymphocyte, B lymphocyte, NK cell alexin, which decreases immunity of organism.

雏鸡硒缺乏降低了红细胞免疫力；同时降低了红细胞对特异性免疫的调节作用，主要表现为降低了吞噬细胞的吞噬能力、清除循环免疫复合物能力、机体识别和携带抗原能力以及对T、B淋巴细胞、NK细胞补体的活化过程的免疫调节作用，结果使机体免疫力下降。

In this paper, a criterion for roots in moduli not exceeding one of an algebraic equation with complex coefficients is proposed.

本文提出了复系数代数方程的根按模不超过一的一个判别法。

In the view of complex algebraic expression of 3D point from the positioning model of binocular vision, according to the independence of imaging-model-parameters, a method of single-parameter analysis positioning errors was proposed to facilitate the simulation.

针对视觉定位模型求解空间点表达式复杂的问题，为便于仿真，根据成像模型参数的相互独立性，提出了一种单参数分析定位误差的方法。

Imaginary unit, real part , imaginary part , the algebraic form of complex numbers.

给出复数、虚数单位，实部、虚部、复数的代数形式。

In the light of the complex, high-level and non-linear feature of the mathematical model which describe the transport of the coalbed methane, this paper study the fully-implicit solving method of the mathematical model in detail. Based on the complexity of the algebraic equations which are formed eventually, according to the alternating direction implicit difference pattern, this paper use the iterative method and the fully main element Gauss-Jordan eliminating method to solve equations, which is to use the iterative method to determine coefficient matrix and use the fully main element Gauss-Jordan method to solve th linear algebraic equation group, at the same time of studying the solving method of the mathematical model, according to the devising requirement of FORTRAN77 program structure, this paper draw up computer program and form the corresponding computer model, and verify the validity and reliability of the model in theory by operating the model.

重点研究了模型内、外边界及有关参数的处理，针对描述煤层甲烷运移的数学模型是一个复杂、高阶非线性数学模型的特点，详细研究了模型的全隐式求解方法，根据最后形成的代数方程组的复杂性，按交替方向隐式差分格式，采用迭代与全选主元高斯约当消去法相结合的方法求解方程：即确定系数矩阵采用迭代法，求解线性方程组时采用全选主元高斯约当消去法，在研究模型解法的同时按FORTRAN结构化程序设计的要求，编制计算机程序，形成相应的CBMRS计算机模型，并通过模型的运行从理论上证明了模型的正确性与可靠性。

This paper discussed the algebraic multiplicity of the complex eigenvalues of population operator.

讨论了人口算子复本征值的代数重数问题。

It obtains that the transport operator A has no complex eigenvalue s, and the spectrum of the transport operator A consists of finite real isolated eigenvalues which have a finite algebraic multiplicity in trip Pas.

本文研究了板几何中一类具各向异性、单能、均匀介质迁移算子A的谱，得出了该算子A在带域Pas中无复本征值和由有限个具有限代数重数的实离散本征值组成等结果。

For the head-teacher of the class said that I had seriously broken the school rules,which led me to a three-day suspend class.

为什么呢？因为我的班主任说我严重的违反了校规，于是让我停课三天。

Many of them believe that the conversion of thousands of working-class folk in England spared that nation from the mass carnage and the tyranny that came with the revolution in France.

他们之中有许多人相信，在英国数以千计的劳工阶级之悔改信主使英国免於遭受如法国大革命所造成的大屠杀和专制暴政。