环

The epoxidation of of various olefins was carried out using LDH-F with Mg/Al=5 as the catalyst and H2O2 and benzonitrile as the oxidants. This catalytic system has excellent catalytic activity. The conversion and selectivity are both above 95% when using styrene, indene, allyl alcohol, and allyl chloride as the substrates.

以Mg/Al=5的LDH-F为催化剂，H2O2和苯甲腈为氧化剂对不同官能团化烯烃进行环氧化反应，结果表明，此催化体系具有良好的催化性能，在苯乙烯、茚、丙烯醇和烯丙基氯环氧化反应中转化率和选择性均在95%以上。

We try to use a modified Bernstein polynomial to reduce the number of variables when calculating the circle array. Finally we use PSO to optimize the circle array and obtain a beam form with a flat top which is needed in the practical design.

在计算圆环阵时尝试引入了修正的波恩斯坦多项式以减少需要优化的变量，并结合工程上的需要，用粒子群优化算法给圆环阵赋行计算得到了主波瓣是平顶的方向图。

Based on the analysis of bibliographer and evaluation of the principles of different processes, the novel process for synthesis of the new type of polyheterocyclic disperse dyestuff , unsymmetrical benzodifuranones and its intermediates was studied in the dissertation.

论文在查阅国内外有关文献基础上，对不对称苯并二呋喃酮系新型稠杂环分散染料的分子设计、应用特性及研究进展作了概述，对此类稠杂环分散染料及其中间体的合成路线和方法作了综合评述。

The dynamic stability of this system is discussed by the Hopf bifurcation theory and the condition of the limit cycle occurring is given.

应用Hopf分岔理论讨论了时滞动力系统动态稳定性，给出了系统产生极限环的条件，最后用数值模拟的方法研究了时滞参数对系统极限环幅值的影响。

In chapter 3, the stability and bifurcation of the equator of a cubic system are investigated.

在第三章中，我们研究一类三次系统的赤道环的稳定性和极限环分支问题。

This indicated that, with the different pH values in solution, the adsorption site of biliverdin could be changed.

在酸性溶液中，胆绿素分子环C上的氮原子和内酰胺环A上的氧原子发生了质子化。

The first part of this thesis is basic on the generalized Hamming weights of linear codes over rings and arranged as follows: In section one, we first introduced the definition of generalized Hamming weights and weight hierarchy over binary field GF (2) and its extension to nonlinear codes over GF (2) and linear codes over rings.

本文的第一部分就是围绕环上线性码的广义Hamming重量这个课题展开的，主要内容如下：第一节，首先介绍了GF(2)上线性码的广义Hamming重量和重量分级的概念，以及这些概念是如何被推广至非线性码及环上的线性码上的。

Power-law fluid is used to describe the Non-newtonian rheological property of the produced fluid in a polymer-driving well; the governing equations, boundary and initial equations of power-law fluid in eccentric annuli with the inner cylinder reciprocating axially is established in bipolar coordinates system; formulas of instantaneous flow rate and stress distribution on the outwall of the inner cylinder of the unsteady flow of power-law fluid in eccentric annuli with the inner cylinder reciprocating axially are established.

在理论上，用幂律流体模型描述了聚合物驱油井产出液的非Newton流变性；建立了双极坐标系下幂律流体在内管做轴向往复运动的偏心环空中非定常流的控制方程及边界条件和初始条件方程；建立了双极坐标系下幂律流体在内管做轴向往复运动的偏心环空中流动时瞬时流量和流体在内管壁上的压力分布计算公式。

Third, sodium sulfoxylate formaldehyde is a kind of bleaching powder used in industry, which is prohibited from adding to food. In this part, we take it as an object to study, by using ion chromatography instrument which is equipped with autech DS-PLUS?

本章利用荧光光度法和紫外吸收分光光度法研究了核酸对环丙沙星-Tb~(3+)体系的荧光增强效应及其影响因素，探讨了其作用机理，提出了环丙沙星-Tb~(3+)配合物与核酸的作用模型，并建立了DNA的选择性测定方法，并将其运用于合成样与血清中DNA含量的测定。

A their blotting paper tree plant drawing - memory grows as if in the fog, ring in ring, a series of wedding ceremonies.

在雾他们的吸墨纸树似乎一张植物图画-记忆生长，圆环在圆环，一系列的婚礼。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。