Sea trial researches on the measurements of passive source space distribution imaging and positioning

The technology of source space distribution imaging measurement is a passive object positioning method with high precision in the near field, which also can get the distribution image of ship＇s radiated noise sources and locate the ghts of the target. The sea trials have been carried out, and the results validate the feasibility and practicability of this tech-nology. The researches indicate that the measurement precision can be achieved at the meter level within the range of 200 m using the uniform linear array which has the length of 45 m and 10 elements, and the method shows good robustness. The results also provide that the general ship can be simplified as single highlight model at 2-10 kHz in the near field and the catamaran is double highlights while its two propellers are working at the same time.     

电子束固化技术的现状和发展

概要介绍了国内外电子束（ＥＢ） 固化技术的现状；重点讨论了我国ＥＢ固化技术的发展方向及发展之路     

HL—2A主机安装前的准备

HL－2A是我院在建的大科学工程。HL－2A的主要主要部件是我院从德国ASDEX拆运回来的，进行部分改进、修复和调整后将重新安装。主机安装前的相关设计、调研工作以及一些部件加工工作正在进行之中。主机安装中的真空室预装、主机基础及主机安装前应具备的条件和技术准备等问题都将逐步解决和落实。     

基于四阶段DEA的区域技术效率分析

通过运用四阶段DEA的方法,首先分析环境变量对各地区技术效率的影响,并得到过滤掉环境因素影响的技术效率;再运用Bootstrap技术,得到各地区纠偏后的技术效率.结果分析表明:可节约劳动的调整对东中部地区效率变动产生较大的影响,资本调整仅起次要作用;可节约资本与劳动的调整对西部地区效率变动都产生重要影响.环境变量的作用表现为:民营资本、基础设施、产业升级、FDI等因素对提升地区技术效率起重要作用.     

Analysis on absolute measurement of optical coating absorption loss based on photothermal detuning technique

Based on the photothermal detuning technique, the three linear relations among reflectance （or trans- mittance）, temperature rise, and pump beam power are studied to achieve the absolute measurement of absorption loss. The relation between temperature and reflectance and the calculation accuracy of tem- perature rise on sample surface have great impacts on the measured result. The influences of parameters involved in the method and the relation between temperature and reflectance and the temperature model of sample surface are also studied. The results show that the absolute absorption loss of optical coatings can be achieved by the proposed method. The measurement accuracy depends on the temperature model and the relation between temperature and reflectance. The linear relation between reflectance and temper- ature rise has largest slope when probe beam wavelength is 632.8 nm and incident angle is 28°. The linear relation slope between temperature rise and pump beam power decreases with the growing of beam size and modulation frequency. The results provide theoretical and experimental supports for the perfection and further application of the photothermal detuning technique.     

动态

融通停牌凸显美国投资者对中资公司担忧 融通金融技术有限公司虽然名不见经传，但这只在美国市场停牌的中资公司股票却让投资者心存扣忧。     

许越副教授在本刊发表的论文入选“2009年中国百篇最具影响国内学术论文”

日前,由中国科技技术信息研究所发布的中国百篇最具影响的优秀学术论文正式揭晓,北京航天航空大学化学与环境学院许越副教授在《中国稀土学报》2005年23卷第一期40~43发表的论文:《AZ91镁合金表面稀土转化膜的制备及耐腐蚀性能研究》入选2009年中国百篇最具影响国内学术论文。     

Method to accurate calibrate deposition rates of EUV multilayer coatings

Random thickness error is an important factor which effects the calibration accuracies of deposition rates for extreme ultraviolet （EUV） multilayer coatings fabricated by sputter deposition techniques. A least square fitting method is proposed to determine deposition rates and extract random thickness errors accurately. The validity of this method is shown by evaluating two deposition systems with control abilities of -0.1 nm and better than 0.01 nm respectively.