Evidence of potential change in nonsequential double ionization

Recently,the quantitative rescattering model(QRS)for nonsequential double ionization(NSDI)is modified by taking into account the potential change(PC)due to the presence of electric field at the time of recollision.Using the improved QRS model,we simulate the longitudinal momentum distributions of doubly charged ions He2+by projecting the correlated two-electron momentum distributions for NSDI of He onto the main diagonal.The obtained results are compared directly with the experimental data at different intensities.It is found that when the PC is considered,the width of momentum distributions reduces and the agreement between theory and experiment is improved.     

中国联通和华为携手打造基于"一朵云"的5G+工业互联网解决方案

中国联通作为全球通信业的领导者之一,长久以来联合华为及其他垂直行业伙伴积极探索5G创新技术和应用解决方案,深入生产业务场景,助力千行百业实现数字化转型,引领全球5G to B发展方向.历经众多行业的丰富实践,中国联通和华为通过结合创新技术开发,面向工业制造领域的5G to B商用目标,打造了基于一朵云的5G+工业互...     

城市地形对电波传播的影响研究

随着科技的日新月异,我国通信技术得到飞速的发展,无线电波在人们的工作和生活中发挥越来越重要的作用。怎样提升无线电波的应用质量,是相关部门一直探索的课题。为了掌握无线电波在移动通信中的传播规律以及无线信道的特征,文章进行了城市地形对电波传播影响的试验,测量的对象是距离基站2.5 km处8个不同的测量点,测量目的是研究接收的信号电平状态和规律,并对城市地形对电波传播的影响进行研究。     

Boundary-Dependent Chaotic Regions for a Bose-Einstein Condensate Interacting with Laser Field

Spatial chaos of a Bose Einstein condensate perturbed by a weak laser standing wave and a weak laser δ pulse is studied. By using the perturbed chaotic solution we investigate the new type of Melnikov chaotic regions, which depend on an integration constant co determined by the boundary conditions. It is shown that when the │co│ values are small, the chaotic region corresponds to small values of laser wave vector k, and the chaotic region for the larger h values is related to the large │co│ values. The result is confirmed numerically by finding the chaotic and regular orbits on the Poincarg section for the two different parameter regions. Thus, for a fixed co the adjustment of k from a small value to large value can transform the chaotic region into the regular one or on the contrary, which suggests a feasible method for eliminating or generating Melnikov chaos.     

带有低温前置放大器的灵敏快速GaAs光导器件

本文介绍了一个灵敏的远红外(100～400微米)探测器系统,它包括液氦致冷GaAs光导器件,低温前置放大器和室温后置放大器。系统的带宽是1赫～30兆赫,比InSb热电测辐射热计大10倍。     

5G+智慧钢铁解决方案助力华菱湘钢转型升级

5G商用一年多以来,中国涌现出机器视觉检测、精准远程操控、现场辅助装配等一系列5G工业互联网应用成果,有力地推动了生产制造更加精准、安全、智慧、高效.在通信世界全媒体主办的"2020年度ICT行业龙虎榜暨优秀解决方案"评选活动中,"5G+智慧钢铁(华菱湘钢)解决方案"凭借创新技术、灵活部署等卓越表现,荣获"2020年I...     

智能高精度温度控制器

<正> 本文介绍的智能高精度温度控制器以8031单片机为核心部件,采用双向可控硅调功方式,利用电接点水银温度计进行温度设置,通过对电接点水银温度计的接通、断开周期的调控实现对控温设备温度的控制。     

中国移动携手华为打造端到端NB-IoT解决方案,加速产业成熟

近年来,随着城镇化、信息化的不断推进,物联网已上升到社会基础设施的高度,国家政策进一步牵引NB-IoT(窄带物联网)产业健康发展,物联网逐步进入规模部署、融合创新、智慧运营的新阶段,并形成多方共赢的生态体系.     

智能云网使能千行百业为数字经济注入新动能

近日,由通信世界全媒体主办的 "2020年度ICT行业龙虎榜暨优秀解决方案"评选活动把ICT产业链带入高光时刻.在此次活动中,华为推出的基于智能IP理念的智能云网解决方案凭借敏捷、高品质、高安全等卓越表现,荣获"2020 ICT行业优秀解决方案奖".