并激

Aimed at the use of underwater active detection system, an analog pretreatment circuit is designed. More than one amplifier and two filters are used to process the signal. The signal can be amplified and self-excitation is avoided. The series of AD867X are used to restrain the circuit noise.

针对水下主动探测系统的应用，设计了一种模拟预处理机，该电路采用分级放大结构，并使用两级滤波器对信号进行滤波处理，在达到对信号放大倍数要求的同时避免了放大器自激，采用噪声性能好的AD867X系列芯片有效抑制了电路噪声对信号的影响。

In this thesis, the self-excited oscillation in HVDC circuit breaker is investigated. And the main problems in the development of HVDC circuit breaker have been summarized.

本文对高压直流断路器的自激振荡问题进行了深入的研究，并分析和介绍了高压直流断路器的发展现状及研制中所面临的主要问题。

Considered the factor of damping,a single degree of freedom s dynamic model of the high-speed cam mechanism is established.Choosing the law of sine acceleration motion as the excitation function,a displacement and acceleration dynamic response equations of the main vibration phase and residual vibration phase,the working dynamic response change curve through the inferential reasoning working end movement equation is derived.The result is obtained that different period and damping ratio have different impact

建立了考虑阻尼因素的等效单自由度高速凸轮机构的动力学模型，以正弦加速度运动规律方程为激振函数，推导出了从动件系统主振段和余振段的位移和加速度动态响应方程并绘制出了动态响应变化曲线，得出了不同阻尼比和周期比对主振段和余振段的动态响应，从而为高速凸轮机构的合理设计提供了一定的理论依据。

To understand the mechanism of the luminescent enhancement for the nanocomposites,the measurements of steady fluorescence emission,fluorescence lifetime and spin-lattice relaxation time ( t 1) of the individual carbon atoms in MEH-PPV for the nanocomposite films were carried out.

结果激发态激子自淬灭的几率降低，稳态荧光量子产率提高和动态荧光寿命的延长；通过共轭碳原子的自旋-晶格弛豫时间的测定，观察了MMT对聚合物分子运动的影响，并由此探讨了MEH-PPV凝聚态与光物理性质的关系。

The concept of magnetic suspending hard disk is put forward,the basic principle of active magnetic force bearing with 5 freedom based on coupling excitation is introduced,the calculation formula of magnetic force and design formula of main structure parameters are inferred.

提出磁悬浮硬盘的概念，介绍了基于耦合激磁的 5自由度主动磁力轴承的基本原理，并推导了磁力的计算公式及其主要结构参数设计公式。

Transferred the NP-1 gene into C. ellipsoidea by electroporation with high efficiency expression vector pBinUΩNP1. PCR, Southern blot and Northern dot blot analysis of the G418resistant alga strains indicated the stable integration and correct transcription of NP-1 in C. ellipsoidea genome. In vitro antagonistic assays showed the proper expression of defense gene in C. ellipsoidea. Transgenic C. ellipsoidea is antagonistic to gram negative bacteria—Bacillus subtonic, gram positive bacteria—Escherichiacoli and fungi—Fusarium oxysporum to some extent.

以椭圆小球藻完整细胞为受体，采用电激转化法将连接在高效表达载体pBinUΩNP1上的兔防御素NP-1基因导入小球藻，通过PCR、Southern杂交、Northern点杂交对转基因小球藻进行了分子检测，同时通过体外离体抑菌实验检测了兔防御素NP-1基因表达产物的活性，结果表明NP-1基因已稳定整合到小球藻基因组中，并进行了正确转录和表达。

Our main work is as follows: the stable laser mode theory in uniform plasmas is extended to non-uniform plasma cases; the discussion of the sufficient and necessary conditions for laser self-focusing in uniform plasmas is developed to non-uniform plasma cases; a quantitative approach to judge the impact of different plasma density distribution on laser self-focusing is proposed; the evolution properties of asymmetric laser filed in non-uniform and uniform plasmas are discussed and mechanisms that symmetric channel-like plasmas can confine the laser centroid around the plasma channel axes and symmetrize initially asymmetric laser beams are proposed; the formation of solitary standing wave in moderate plasma density is studied by PIC simulations and can be explained by stimulated Raman scattering of laser beams in plasmas.

主要工作为：把均匀等离子体中激光的稳定模理论推广到横向非均匀等离子体情形；把均匀等离子体中激光自聚焦的充分和必要条件的讨论推广到横向非均匀等离子体情形；给出横向密度分布不同的等离子体影响激光自聚焦的定量判据。讨论了初始不对称的激光场在横向非均匀及均匀等离子体中的演化特性，并提出了具有对称腔道结构的等离子体箍缩激光质心和对称化初始不对称激光场的物理机制。用粒子模拟讨论了激光场在等离子体中形成孤立驻波的过程，认为前向受激拉曼散射是发生此现象的可能机制。

A mathematical model of the vibration at the upper segment of a pile when there exist severe defects is put forward based on theoretical analysis, and the curve characteristics of its low strain test is described according to engineering practice under condition of transient shock.

文摘：从理论上给出了当基桩存在浅部严重缺陷时，在受到瞬态激振力的情形下，桩体上段振动的数学模型，并结合工程实践，描述了其低应变实测曲线的特征。

It is definitely a good energizing tonic and will help your health to a certain degree.

它无疑是一个好激补品，并会帮助你的健康做出了一定贡献。

Trichloroethylene at the doses of 1500 and 3000mg/kg induces obvious oxidative stress in rat liver tissue and causes DNA damage in rat hepatocytes.

三氯乙烯在1500和3000mg/kg剂量条件下染毒大鼠后，造成肝组织明显的氧化应激并引起肝细胞DNA损伤。

In the United States, chronic alcoholism and hepatitis C are the most common ones.

在美国，慢性酒精中毒，肝炎是最常见的。

If you have any questions, you can contact me anytime.

如果有任何问题，你可以随时联系我。