Finally , we study the effect of longitudinal wakefield in the propagation of intense laser in plasma and find that this effect leads to asymmetric self - phase modulation of the pulse 最后研究了尾波场效应对激光传输的影响，发现纵向尾波场效应将导致激光脉冲不对称自相位调制。
Carried out by global real estate agent cushman wakefield , ecm interviews senior managers and board directors in charge of location from 507 of the top european companies 在国际房地产机构高纬物业的大力支持下， emc对欧洲507个大型企业专管投资场所的高级经理人和董事长进行了采访。
Cushman wakefield limited is always willing to provide employment opportunities to the disabled . currently , persons with different disabilities have been engaged to perform clerical duties 高纬物业顾问有限公司非常乐意提供就业机会给残疾人士，现时聘用了不同类别的残疾人士负责文职工作。
The pulse has a slow rising wavefront which stimulates the " raman scattering instability " to accelerate the electrons firstly and a sharp falling rear part which excites wakefield to trap electrons secondly 鉴于“受激naman散射”在尾流场加速电子方面的重要性，我们还研究了长脉冲激光激发“受激naman散射”的情况。
Mrs yau took the opportunity to establish her contacts with members of the parliament , research institutes , businessmen and opinion formers at a luncheon hosted by sir peter wakefield , chairman of asia house 尤曾家丽利用参加asiahouse主席peterwakefield爵士邀宴午餐的机会，与多位国会议员、研究机构人员、商界及舆论界人士建立联系。
The saturation time in our simulation is consistent with the prediction of the theory . furthermore , we also studied the propagation of two pulses with inverse phase . in this case , the wakefield excited by the first pulse will be absorbed by the second pulse which shifts to higher frequency 此外，我们还研究“位相相反”的两个脉冲在稀薄等离子体中的传播，第二个激光脉冲由于吸收了前一脉冲激发的静电场，频率向高频方向漂移，得到频移的大小与符合理论推测。
Firstly , the propagation of intense laser light in ionizing gases is analyzed including the ionization - modulation instability , the vectorial and nonparaxial effects , and the mechanism of laser energy loss . secondly , we analyze the propagation of intense laser light in plasmas , and effects such as the weakly relativistic nonlinearity , the ponderomotive force and the wakefield are analyzed 文中对强激光在电离气体中传输的电离不稳定性、矢量非傍轴传输和能量损耗机制，以及强激光在等离子体中传输的弱相对论性非线性效应、有质动力作用和尾波场效应等都作了基本的分析。
The wakefield excited by an ultrashort and ultrahigh laser pulse propagating through tenuous plasma can accelerate electrons to extreme high energy . this can be used as a mechanism to design minitype electron accelerator . this thesis is devoted to studying those issues relevant to the wakefield accelerator , namely the laser wakefield accelerator ( lwfa ) , laser wakefield accelerator driven by multiple pulses ( mp - lwfa ) , plasma beat wave accel - erator ( pbwa ) and self - modulated laser wakefield accelerator ( sm - lwfa ) 本文的目的是：利用粒子模拟方法，研究和比较激光尾流场加速电子的四种主要方案：短脉冲激光尾流场加速( lwfa ) 、多脉冲激光尾流场加速( mp - lwfa ) 、拍频束尾流场加速( pbwa ) 、自调制激光尾流场加速( sm - lwfa ) 。
We focused our discussions on the mechanism of saturation of the wakefield and the electron parametric instabilities which affect the process of the wakefield generation and electrons acceleration . we developed a 2 - dimension distributed parallel pic code under mpi parallel environment and got a good speedup ratio tested on yh - iv and pc computer groups 为了解决研究激光和稀薄等离子体相互作用所需的大量计算，我们研制了21 2d分布式粒子模拟并行程序，在微机群和巨型机yh ? iv对程序并行性能进行了测试得到了较高的加速比。
The optimum intervals between the two pulses is about 1 . 7 in our simulation which is much longer than the commonly cited value 1 . 5 . 3 . in the sm - lwfa simulation , we turned our attention to the wakefield generation and electron acceleration driven by the " self - modulated instability " and " side stimulated raman scattering " 我们首先提出“三角脉冲激发尾流场加速电子”的方案，利用“三角脉冲”平缓的上升沿激发“受激raman散射”预加热电子，其陡峭的下降沿激发尾流场可以使更多的电子被“捕获” 。
