Quantitative surface analysis by Auger and x-ray photoelectron spectroscopy

Recent developments in quantitative surface analysis by Auger (AES) and x-ray photoelectron (XPS) spectroscopies are reviewed and problems relating to a more accurate quantitative interpretation of AES/XPS experimental data are discussed. Special attention is paid to consideration of elementary physical processes involved and influence of multiple scattering effects on signal line intensities. In particular, the major features of core-shell ionization by electron impact, Auger transitions and photoionization are considered qualitatively and rigorous approaches used to calculate the respective transition probabilities are analysed. It is shown that, in amorphous and polycrystalline targets, incoherent scattering of primary and signal Auger and photoelectrons can be described by solving analytically a kinetic equation with appropriate boundary conditions. The analytical results for the angular and energy distribution, the mean escape depth, and the escape probability as a function of depth of origin of signal electrons as well as that for the backscattering factor in AES are in good agreement with the corresponding Mote Carlo simulation data. Methods for inelastic background subtraction, surface composition determination and depth-profile reconstructions by angle-resolved AES/XPS are discussed. Examples of novel techniques based on x-ray induced photoemission are considered.     

提高独立学院英语专业学生学习动机的策略

学习动机是影响英语学习成功的重要因素。最近几十年学习动机已经成为了第二语言习得研究的热门话题。越来越多的英语教育学者也都参与研究学习动机对英语学习者的作用。本文主要采用Tremblay and Gardner’s（1995）学习动机的模式,对独立学院的英语专业学生进行学习动机的分析,最后提出提高独立学院英语专业学生学习动机的几点建议。     

星载激光测高仪接收放大器参数的优化设计

为使星载激光测高仪满足测量精度的需求,分析了接收放大器部分的设计原则与要求,对带宽、信噪比、探测灵敏度和放大倍数等主要性能参数进行了理论分析与研究,得到了性能参数的关系和优化的参量。理论结果表明,在激光测高仪测量范围为450 km~650 km,激光脉冲宽度为8 ns~12 ns,工作波长为532 nm与1 064 nm的情况下,对放大器性能参数进行分析计算,可以满足虚警率为1%的星载激光测高仪的设计需求。     

在面向服务的光网络中SLA的扩展及应用研究

在面向服务的光网络中，光网络资源被封装成有状态的Web服务资源（WS-Resource）。利用扩展的服务等级协商（SLA）机制，实现了对动态变化的光网络WS-Resource的协商与调度。另外在此基础上，增加了违例处理，完善了SLA处理流程。     

预张拉纤维布约束混凝土圆柱预应力损失试验

为了对混凝土墩柱有效施加环向预应力,研制了一种自锁式锚具用来环向张拉纤维布,从而对核心混凝土提供主动约束应力,提高混凝土墩柱的强度和延性.根据自锁式锚具的施工工艺,分析了引起预应力损失的主要原因,针对摩擦损失、碳纤维布应力松弛损失、混凝土收缩徐变损失等各种影响因素进行了试验研究和理论分析,得到了各项预应力损失的发展规律及其与相关影响因素的关系,提出了减少预应力损失的措施.     

SaaS应用中基于SLA的资源分配研究

随着云计算的普及,软件即服务(Software as a Service,SaaS)得到了广泛的关注.SaaS应用中,需要满足客户服务等级协议(Service Level Agreement,SLA)要求、减少SLA服务违例的同时,尽量提高系统资源的利用率,这对资源分配策略提出了挑战.提出了SaaS模式下的基于SLA的资源分配策略:基于对客户请求动态变化的分析,针对"首次租用服务"和"租用服务升级"两种请求类型,提出了一种用户请求与底层资源的映射策略;提出了提高虚拟机重用度的基于SLA的资源效率优化分配算法.实验表明,该资源分配算法可以在有效保证服务质量的同时,提高资源的利用率.     

Analysis of the Internal and External Factors Involved in Second Language Acquisition

Materialist dialectics holds that internal causes are the basis of change and the external causes are the condition of change, and that external causes become operative through internal causes. This law can be applied into SLA. The internal causes and external causes influence SLA greatly. This paper mainly discusses the factors involved in SLA process.     

Krashen二语习得理论在五年制高职小学教育专业英语教学中的运用

分析五年制高职小学教育专业英语教学现状,介绍Krashen二语习得理论中的5个假设及其对教学的启示,改革英语教材,结合《新概念英语》教材的基本原理和新课堂模式的构建,阐述Krashen二语习得理论运用于五年制高职小学教育专业英语教学的可行性和有效性。     

国内过渡语语用学研究综述

过渡语语用学作为一门新兴的交叉学科,丰富了语用学、二语习得和跨文化交际学的内涵。语际语用学从语用的角度为过渡语研究提供了理论依据。本文对国内过渡语语用学的发展历程和研究现状进行了归纳总结,并指出该研究存在的问题和发展前景。