甲磺酸帕珠沙星紫外光谱性质的研究及应用

在0．1mol／L HCI介质中，甲磺酸帕珠沙星的紫外吸收最强且稳定，最大吸收峰在247nm处，另外在331nm处也有显著吸收．在247nm处，吸光度与药物质量浓度在0～30．0mg／L（R=0．99996）范围内呈线性关系，检测限为0．026mg／L,在331nm处，吸光度与药物质量浓度在0～90．0mg／L（R=0．99995）范围内呈线性关系，检测限为0．144mg／L．该方法操作简便快捷，灵敏度较高，体系稳定．用于合成样品中甲磺酸帕珠沙星的测定，结果满意．     

SOME APPROXIATIONS TO S(U(?)G(·))

Approximations,especially,ε-approximation,to a supportfunction in the Lipschitzian sense and some properties are studiedin this paper.     

HIV infection of primate lymphocytes and conservation of the CD4 receptor

The CD4 T-lymphocyte differentiation antigen is an essential component of the cell surface receptor for human immunodeficiency viruses (HIVs) causing AIDS (acquired immune deficiency syndrome) (refs 1-3). Peripheral blood lymphocytes of apes, New World and Old World monkeys express cell surface antigens homologous to CD4 of human T-helper lymphocytes. The cells of several of these species can be infected in short term culture with diverse strains of the type-1 or type-2 human immunodeficiency viruses (HIV-1 and HIV-2). HIV-1 is the prototype AIDS virus, and HIV-2 is the second type of AIDS virus, prevalent in West Africa. Infection of the primate cells correlates with evolutionary conservation on CD4 of one particular epitope cluster, and is inhibited by treatment of the cells with monoclonal antibodies to this epitope. The capacity of HIV to replicate in simian cells may provide a means for evaluating antiviral drugs and vaccines.     

计算机辅助财务管理的实践与思考

对计算机辅助财务管理中的借贷记账法、产品成本计算方法等问题进行了探讨。     

Characterization of low-purity clays for geopolymer binder formulation

The production of geopolymer binders from low-purity clays was investigated. Three low-purity clays were calcined at 750℃ for 4 h. The calcined clays were chemically activated by the alkaline solutions of NaOH and Na₂SiO₃. The compressive strength was measured as a function of curing time at room temperature and 85℃. The results were compared with those of a pure kaolin sample. An amorphous aluminosilicate polymer was formed in all binders at both processing temperatures. The results show that, the mechanical properties depend on the type and amount of active aluminum silicates in the starting clay material, the impurities, and the processing temperature.     

氯化银纳米晶的自陷落激子态产生铌碲酸盐玻璃的光限幅效应

利用熔融法结合扩散控制法制备了含有氯化银(AgCl)纳米晶的碲铌氧化物玻璃样品, 运用吸收光谱观测到532 nm附近AgCl的自陷落激子吸收峰. 通过拉曼光谱表征获得玻璃的网络结构参数, 结合Jahn-Teller模型分析了自陷落激子的形成机制. 利用532 nm皮秒脉冲激光研究了玻璃在近共振区的光限幅效应, 通过Z扫描实验测量了样品的非线性吸收系数, 研究表明在近共振和共振区自陷落激子态吸收导致光限幅效应的增强.     

西太平洋热带气旋路径对北京PM10污染的预示作用

利用北京地区空气质量监测资料和NCEP再分析资料, 分析了北京地区PM10污染过程与天气形势和天气系统的关系. 特别是通过对海平面气压场和西太平洋热带气旋路径的分析, 发现西太平洋热带气旋路径对北京地区PM10污染的发生具有预示作用, 即当热带气旋北上并在朝鲜半岛或日本登陆的情况下, 北京地区一般受持续均压场等弱中尺度天气系统控制, 经常容易发生区域性的PM10空气污染过程. 这为开展北京空气污染预报预警和污染控制, 提供了一个有效的预报方法和手段.     

2008年8月1日日全食的日冕结构和亮度分布

日冕是太阳的外层大气, 日冕活动影响日地空间环境和太空天气以及地球. 日全食是观测研究日冕的良机. 在2008年8月1日的日全食期间, 我们用CCD照相机与天文望远镜组合拍摄了一系列日冕像和日面偏食像. 本文选取部分图像, 进行数字图像处理和分析, 给出初步结果, 揭示日冕的一些活动结构, 测定日冕两极和赤道的亮度径向平滑分布. 虽然太阳活动处于极小期, 但日冕结构仍是不对称的, 不仅显示赤道区比两极区延展, 即使赤道东、西和南、北极区也有较大差别. 赤道东侧的冕流, 尤其东南方的大冕流很显著. 南极区比北极区的冕羽由更多的极射线组成, 这些结构也可由他人观测的及SOHO卫星的当天日冕图像佐证. 日冕赤道区和极区的亮度径向分布接近于Van de Hulst的太阳活动极小期模型, 但存在因日冕结构而比该模型的明显偏离, 这些日冕结构也显示在日冕的等亮度图上.     

ZrO2 strengthened NiAl/Cr(Mo,Hf) composite fabricated by powder metallurgy

The ZrO2 ceramic particles strengthened NiAl/Cr(Mo,Hf) composite was fabricated from the rapidly solidified NiAl/Cr(Mo,Hf) pre-alloyed powder and the ZrO2 powder by powder metallurgy technique.Microstr...     

Progress of applied research on TiO<Subscript>2</Subscript> photocatalysis-membrane separation coupling technology in water and wastewater treatments

Photocatalysis-membrane separation coupling technology has been a heavily researched area in water and wastewater treatment during recent years. The membrane separation process allows the photocatalyst to be easily separated, recovered and reused. More significantly, the membrane is efficient to maintain high flux of membranes as the photocatalyst can reduce the membrane fouling problem which is a hindrance in the development of membrane process. Moreover, some synergistic effects can also be produced, and ...