电子对产生

随着激光技术的发展，在超强激光脉冲中产生高能量粒子的理论研究和实验研究引起了人们极大的关注，特别是在强电场存在下真空中正负电子对产生问题的研究具有重要的意义。

With the development of laser technology , the theoretical and experimental studies of production of high-energy particles in ultra-intense laser pulse has aroused great concern , especially electron-positron pair production from vacuum in the presence of strong electric field has become an important topic .

核碰撞中直接电子对产生截面的计算

A Calculation of Production Cross-Section of Direct e ~ + e ~ - Pairs in Nuclear Collisions

通过比较我们发现圆偏振激光场中的正负电子对产生的几率小于线偏振光中的生产率。

By comparison , we found that the electron-positron pair production probability in the circularly polarized laser field is smaller than the linearly polarized one .

介绍了高能核-核碰撞中直接电子对产生截面的理论结果，计算了高能氧核与核乳胶电磁作用中产生直接电子对的截面。

According to the theoretical result of production cross-section of direct e + e - pairs in high energy nucleus-nucleus collisions , the cross-sections of direct e + e-pairs produced in electromagnetic interactions of oxygen nucleus with nuclear emulsion at high energies are calculated .

均匀电场中Dirac方程的严格解和真空中正负电子对的产生率

The exact solution of Dirac equation under a constant uniform electric field and the electron positron pair creation rate in vacuum

电子正电子对产生

Electron positron pair creation

正负电子对的产生问题已经在很多条件下研究过，如在强库仑场条件和强激光场条件下。

It has been investigated for the electron-positron pair creation in many cases , such as in the strong Coulomb potential and in the strong laser field .

然后，我们在椭圆偏振激光场中分别近似地计算出了低频强场和高频弱场两种情况的正负电子对的产生几率。

Then , we have approximately calculated electron-positron pair production probability for two cases of low frequency elliptically polarized strong field and high frequency elliptically polarized weak field .

变革时期，图书馆期刊工作将不可避免地受到两方面的影响：一是图书馆数字化发展中，电子期刊对它产生的冲击；二是我国加入了WTO之后，对外刊工作的影响。

In the innovation period , the library journal work is inevitably affected by the following two factors : one is from the electronic journal , and the other is the foreign journal .

从原子结构看惰性电子对效应的产生

On cause of " inert electron pair effect " in view of atomic structure

一方面，电子商务对物流活动产生了重大影响。

On the one hand , e-logistics activities had a significant impact .

由于双光子吸收引起自由电子-空穴对的产生。

Electron-hole pair are generated due to TPA effect .

用双晶γ谱仪研究正负电子对的近阈产生

Study of the e ~ + e ~ - Pair Production Near Threshold Using Double Crystal γ - ray Spectrometer

本文从政府的职能、政府的工作效率和政务公开等几个方面阐述了电子政务对政府管理产生的影响。

In this paper , the effects of e government on the function , efficiency , and ventilate of government are analyzed .

用低能弱γ源测量电子对的近阈产生截面

Measurements of the cross section of electron pair production near threshold using a low intensity ~ ( 60 ) co γ ray source

电子商务对社会经济产生巨大影响表现是：在知识经济的发展过程中起着关键的促进作用；

The performance that the A electronic commerce to the social economy is : Gets up the key promoter action in the knowledge economy developing process ;

但长期以来经验告诉人们，晚上玩电子游戏会对睡眠产生有害影响，因为这类刺激使人不玩游戏后仍很清醒。

But anecdotal evidence has long suggested that playing such games at night could have a detrimental impact on sleep because the stimulation keeps one awake even after the game has ceased .

同时实验发现，Zni施主缺陷通过影响与Co的3d电子态之间的电子跃迁数量对磁性产生影响。

It was simultaneously found that Zn ; donor defects influence the ferromagnetic via working on the number of transitional electrons among the 3d electronic states of Co.4 .

以无限深势阱为模型，应用量子力学微扰理论计算了叶绿素中电子跃迁几率，并且求得电子对阱壁产生的压力以及所做的构像功。

Applied perturbation theory of quantum , the electronics transition probability is calculated , but the pressure of the wall of well and conformation work is investigated with the infinite-depth potential well model .

本文介绍了图书馆馆藏发展中的重要组成部分网络型全文电子期刊的现状、特征、选择标准以及电子期刊对图书馆产生的影响，并对部分领域提出一些思考性建议。

The paper introduces the current status , features and standards for choice of the webbased electronic full-text journals taken as an important part of library collection development , and its impact on library service , and puts forth some ideas for people to think over .