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From optical BINOL, the chiral phosphoryl azide compound was prepared. Its application as chiral auxiliaries in the stereoselective ring-opening of meso-epoxides was examined. No obvious asymmetric induction, however, was observed.

从光学活性的联二萘酚出发合成得到了手性磷叠氮化合物，并将其应用于环氧化合物的不对称开环反应中，考察了它作为手性辅助剂在该反应中的不对称诱导效果。

We developed a large scale preparation and purification of a new asymmetric phthalocyanine zinc compound,2-carboxyphthalocyanine zinc.

设计并制备了一种组成和结构单一的新型两亲性酞菁锌光敏剂。

A novel method is presented for efficient local asymmetric regions detection in medical images using image registration and mathematical morphology. First, we extend self-reflexive rigid binary image registration to find the symmetry plane of a gray-scale medical image.

提出一种利用图像刚性配准算法和数字形态学调整近似对称区域、有效挖掘出图像非对称区域，并自动判断头部炎症类疾病的算法。

This type of resolution may be decided at the point of cell division, when asymmetric distribution of regulatory proteins in daughter cells can lead to differential gene expression patterns .

这种分解的类型在细胞分化时就已经决定了。姐妹细胞中的调节蛋白不对称分配时，会导致不同的基因表达方式。

The design, implementation, and characterization of an image-rejection double quadrature conversion mixer based on RC asymmetric polyphase filters are presented.

本文介绍了一种基于阻容多相滤波器的双正交镜像抑制混频的设计、实现和测试。

The melody of the work is reformed on thebasis of the traditional music melody, whose characteristic can summarize as: thehorizontal polytonality, asymmetric phrase, often using the jumped interval, and theexpanded melodic range.

作品的旋律是在传统的基础上加以创新，其特点可以概括为：多调性横向进行、乐句的不对称、广泛使用大跳音程、旋律的上限与下限之间音域的扩展等。

The 3 characters of the safe vegetable products, which are secretiveness of quality, posteriority of utility, and the consumers' suspicion to the product certification, bring many negative effects on production and consumption, such as asymmetric market information, producers' moral risk, reduction of consumer preference and convers choice.

而安全蔬菜质量的隐匿性、效用的滞后性和消费者对产品认证的置疑性带来市场信息不完全，又给生产与消费造成诸多负面影响，如生产者实施"道德风险"、消费者偏好程度降低、消费者的逆向选择等。

This paper first analyses and summarizes the ststus quo and evolution trend of encryption, some common used cryptograph are introduced, including the algorithms used in symmetric cryptosystem and asymmetirc cryptosystem. We describe the theory of each algorithms and compare the elliptic curve cryptosystem with the other two asymmetric cryptosystems to show the advantages of this algorithm. Second, the principle of ECC is discussed, including the math foundation of ECC, basic conception of elliptic curves, constructiong idea of ECC, operation on the elliptic curve and so on. Third, the current attacks of ECC were analyzed deeply, and an algorithm based on limited prime number field was constructed. We analyzed its realizability in theory, and implement it by using certain function of MIRACL software package. Latter half in this paper, the implementation model of a simple elliptic curve encryption system which based on GF has been introduced. The paper also put a deep analysis on the algorithm of point addition and point multiplication.

本文首先对密码技术的发展现状及其发展趋势进行了分析和综述，详细的介绍了私钥密码系统和公钥密码系统的发展，说明各种算法的原理和优缺点，并给出了一些典型的密码体制的简要分析，重点将椭圆曲线算法与其它几种公钥密码算法比较，说明椭圆曲线算法的优势；其次，探讨了椭圆曲线密码体制的原理，包括椭圆曲线密码的数学基础、基本概念、椭圆曲线密码体制的构造思想等问题；第三作者对椭圆曲线的攻击现状作了详细的分析，针对所使用的大素数域F_p，设计了素数域上安全椭圆曲线产生的算法，从理论上做了可实施性分析，从软件上做了具体实现；在本文的后半部分，提出了一个简单的基于有限素数域上的椭圆曲线加密方按算实现模型，并对SECES中设计的点加和点乘运算进行了深入分析。

Pyrazine derivatives have been synthesized. And the 3-keto glycosides can be employed to asymmetric synthesis.

并利用两种邻苯二胺与2-位氧化α-甲基D-葡萄糖苷反应合成了两种含糖吡嗪衍生物。

In this dissertation, Ir-catalyzed asymmetric hydrogenation of quinoline derivatives, pyridine derivatives and exocyclic enamines have been studied.

本论文研究了铱催化的喹啉和吡啶衍生物以及环外烯胺的不对称氢化。

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