激光热致相变核-壳微胶囊的合成与性能

以甲基丙烯酸甲酯作为主要的核单体，甲基丙烯酸缩水甘油酯作为壳单体，叔胺盐作为壳的改性剂，合成了平均粒径为55nm具有激光热致相变性能的核壳微胶囊。用红外光谱对其结构进行了表征；用透射电镜观察了微胶囊形貌；用示差量热分析法、热重分析法测定了热性能、接触角仪测定了相变前后的亲水性，探讨了对相变效果的影响因素。核聚合物的玻璃化转变温度为56.2℃，壳聚合物的玻璃化转变温度为85.3℃；该微胶囊感激光后发生相变，接触角由初始的20°变为93°。     

Lightning activity on the central Tibetan Plateau and its response to convective available potential energy

Lightning flash activities on the central Tibetan Plateau have been studied by using the satellite-based Lightning Imaging Sensor(LIS)database from January 1998 to July 2002.The lightning activity shows a clear diurnal variation on the central Plateau.The peak lightning activity appears at about 17:00 which is 3 h earlier than that in Jingxhou,Hubei in the same latitude belt nearby,indicating that the lightning activity is a sensitive indicator of solar heating on the Plateau.The lightning discharge is weaker on the Plateau than Jingzhou.Hubei and other low-altitude continental regions because of the lower convective available potential energy(CAPE)on the Plateau.The CAPE on the Plateau is 12 times lower than that in Jingzhou,Hubei,and 20 times lower than that in the sea-level region,such as Guangzhou and Florida.However,the sensitivity of lightning activity to CAPE changes on the Plateau is up to 30 times more sensitive than other prominent low-altitude regions.     

Pt胶粒修饰Pt丝微电极对CO的气敏特性研究

介绍了Pt胶粒修饰Pt丝微电极的制作方法，并研究了其对CO的敏感特性，发现在一定的CO浓度范围内，循环伏安扫描的峰电流随CO浓度增加而增加，并成良好的线性关系．同时还研究了电化学活化处理对电极气敏特性的影响，试验结果显示：对修饰电极的电化学活化处理可以降低过电位，增强反应峰电流，削减干扰峰，降低基底电流并使其更平坦．     

残差修正步进模型在社保卡数字照片处理中的应用

针对社保卡安全性问题,提出了将残差修正步进模型(GSMEM)运用于社保卡数字照片处理.为了适应社保卡应用的要求,压缩数字照片既要减少其占用的内存,又要保证算法具备较快的运算速度,以提高社保卡图像边缘的视觉效果.实验结果表明,该方法具有较高的实用性.     

极限周期连分式修正因子的一种新求法

加速收敛在连分式理论中占有重要的地位,对连分式进行加速收敛最常用的方法是选择合适的修正因子;文章借助极限周期连分式与2-周期连分式的性质,针对极限周期连分式的修正因子给出一种新的选取方式,数值例子表明,新的修正因子使得连分式的收敛更快,精度更高。     

基于同步辐射的紫外-真空紫外光谱辐射测量装置的研制

研究基于同步辐射的紫外-真空紫外光谱辐射测量装置. 通过切换前置镜位置来完成同步辐射光源和传递标准光源的测量. 讨论了辐射计偏振特性对测量结果的影响. 根据Schwinger提出的理论公式,利用同步辐射作为基准辐射源,在115～350nm的波长范围测量了作为传递标准的氘灯的光谱辐射亮度,测量不确定度为11%～14%.     

随机扫描振动中结构疲劳寿命的预测

应用应力场强度理论,分析、推导按宇航标准进行随机扫描振动中,复合循环应力作用下材料的应力函数f(iδj)和应力场强度δF1的具体形式,建立随机扫描振动的振动量值与结构疲劳寿命的直接联系,对在高频率(500-2 000 Hz)阶段材料的塑性行为和实验数据进行分析,得到适用于LY12-CZ的寿命修正因数.同时,通过对三因数公式进行修正,得出复合循环应力作用下,预计结构抗振动疲劳寿命的经验公式.     

基于多幅不同曝光量照片的场景高动态范围图像合成

提出了一种恢复相机成像系统光照响应曲线,合成场景高动态范围图像的方法.在满足光学成像系统相反法则的前提下,利用多幅同一场景不同曝光量的照片图像,结合最小二乘原理和B样条函数拟合方法,恢复了相机的光照响应曲线,获得图像中像素值与曝光量之间的映射关系,进而将不同曝光量的场景照片图像融合成一幅高动态范围图像.图像中的像素值与场景中对应点的真实亮度值成正比,扩大了场景图像的表示范围,增加了场景图像中高亮区和暗区的细节特征.实验表明,合成的高动态范围图像效果满意.     

Sn-15%Pb合金电脉冲孕育处理效果时间相关性研究

采用Sn-15%Pb合金作为实验材料,在保持熔体过热90℃的条件下,对其进行不同时间的电脉冲孕育处理.利用金相组织观察和热分析等手段来评价电脉冲孕育处理对合金凝固组织和凝固过程的影响.结果表明:经电脉冲孕育处理后,Sn-15%Pb合金凝固组织发生了明显的变化,凝固组织中的富Sn初生相形态从树枝晶转变为颗粒状;与凝固组织的变化相对应,合金的凝固过程也发生了明显的改变,初生相形核的最低温度有较大幅度的提高;但随着电脉冲处理时间的延长,凝固组织中粒状晶的数量总体呈现出"少-多-少-多"的周期性变化规律;与之相对应,初生相形核温度的变化也随电脉冲孕育处理时间的延长呈现出周期性.     

Simulation and evaluation of the quality and availability of typical GLI ocean image

ADEOS-II satellite will be launched in the near future. It collocates many remote sensing instruments in the same platform. Among them, Global Image (GLI) is considered to be a main sensor which will play a key role. In order to understand the characteristics of future GLI ocean color images, a simulation and evaluation of the quality and availability of GLI typical ocean image has been done. In the paper, we first introduce the simulation models briefly, and simulate typical cases of radiance images at visible channels, in which the radiance distribution is based on geographic location, the satellite orbital parameters and sensor properties. A method, complex signal noise ratio (CSNR) to evaluate the image quality and availability, is developed according to the characteristics of image. Meanwhile, a series of CSNR images are generated from the simulated radiance components for different cases, which can be used to evaluate the quality and availability of GLI images before the ADEOS-II is placed in orbit. Finally, the quality and availability of GLI images are quantitatively analyzed by the simulated CSNR data. The results will be beneficial to the people who are in charge of GLI mission or plan to use the data from GLI.