The Genesis Solar Wind Concentrator Target: Mass Fractionation Characterised by Neon Isotopes

The concentrator on Genesis provided samples of increased fluences of solar wind ions for precise determination of the oxygen isotopic composition. The concentration process caused mass fractionation as a function of the radial target position. This fractionation was measured using Ne released by UV laser ablation and compared with modelled Ne data, obtained from ion-trajectory simulations. Measured data show that the concentrator performed as expected and indicate a radially symmetric concentration process. Measured concentration factors are up to ∼30 at the target centre. The total range of isotopic fractionation along the target radius is 3.8%/amu, with monotonically decreasing ²⁰Ne/²²Ne towards the centre, which differs from model predictions. We discuss potential reasons and propose future attempts to overcome these disagreements.     

逆向工程的关键技术及其研究

综述了逆向工程中实物数字化技术、测量数据的预处理、曲面重建技术、重构曲面的评价和检验等关键技术的发展现状和存在的问题,并对今后的发展方向进行了讨论。     

CFG桩复合地基应力比数值分析

本文采用有限元ANSYS程序对CFG桩复合地基的单桩桩体荷载传递规律、应力比及影响因素进行了分析,得出了减小应力比的方法和措施,对工程可起借鉴的作用。     

Two years of INTEGRAL observation of the BHC IGR J17464-3213

On March 2003, IBIS, the γ-ray imager on board the INTEGRAL satellite, detected an outburst from a new source, IGR J17464-3213, that turned out to be an HEAO-1 transient, namely H1743-322. The spectral and temporal evolutions of the source were observed by INTEGRAL in different periods. Also RXTE observed the source for the first time on 2003 March 29 during a PCA Galactic bulge scan. The source flux decayed below the RXTE PCA sensitivity limit in November 2003, then in April 2004 it was again detected by INTEGRAL. On July 3, 2004 the source was again detected by RXTE/PCA at a 2–10 keV intensity of 16 mCrab and on July 7, reached 69 mCrab. Recently, a new outburst was observed on August 2005. We briefly summarise here the behaviour of the source observed by INTEGRAL from March 2003 to August 2005. The new outbursts of the source and the analysis of all the data collected (now public) give a global view of the spectral and time behaviour of this X-ray transient.     

对“ZY-1”FM1整星热平衡、热真空试验中有效载荷被污染情况的分析

介绍了卫星在热平衡试验后所发现的有效载荷的污染情况,通过对污染提取物的分析和试验设备的再次污染监测,找出了污染源,并对以后的防污染工作提供了借鉴.     

液相色谱仪故障分析与处理

简述了液相色谱仪工作原理，对常见故障进行了分析，并给出了处理方法。     

VO2薄膜制备工艺及电阻开关特性研究

用溶胶－凝胶法在非晶玻璃上制备VO2薄膜，经过熔融、涂膜、烘干和热处理等工艺最后得到电阻相变2－3个量级的VO2薄膜。对烘干温度、熔融温度、膜厚和热处理温度对薄膜电阻开关特性的影响进行了研究。通过XRD（X－ray diffraction)和XPS（X－ray photoelectron spectroscopy）对薄膜的结构和价态进行分析，表明用溶胶－凝胶法制图VO2膜工艺简单，重复性好。     

Time-dependent thermal X-ray afterglows from GRBS

Time-dependent thermal X-ray spectra are calculated from physically plausible conditions around GRB. It is shown that account for time-dependent ionization processes strongly affects the observed spectra of hot rarefied plasma. These calculations may provide an alternative explanation to the observed X-ray lines of early GRBs afterglows (such as GRB 011211). Our technique will allow one to obtain independent constraints on the GRB collimation angle and on the clumpiness of circumstellar matter.     

基于有限元法的隧道荷载模型位移反分析

介绍了一种以荷载模型为求解对象的位移反分析法。它是以通用有限元软件为实验平台，利用隧道位移实测值建立荷载灵敏系数方程，根据最小二乘法原理反求隧道模型的荷载，再将正分析结果和实际值进行对比分析井重新调整隧道荷载模型，最终获得较为符合实际的隧道荷载模型。该方法的优点是既考虑了岩土松动荷载效应又能体现支护结构与周围岩土体的共同作用，且具有较好的操作性。     

养老金替代率的灵敏性分析

文章推导出了企业职工养老金替代率的计算公式,对影响替代率的五个因素分别进行了灵敏性分析,给出了替代率的最佳可行区域.