钯作基体改进剂FIA－HG－GFAAS法测定锗及其机理研究

采用钯，钯－镁作基体改进剂，ＦＩＡ－ＨＧ－ＧＦＡＡＳ法成功地测定了锗。灵敏度、精密度和分析速度都得到很大的提高。峰值吸收的特征质量８．０ｐｇ，检出限１０．９ｐｇ，相对标准偏差０．３４％，同时探讨了基体改进剂钯的稳定作用机理及锗在石墨管中的原子化机理。     

Determination of generation lifetime fromC-t transients under linear voltage ramp bias

When a linear voltage ramp is applied to the gate of a MOS capacitor, a capacitancetime (C-t) transient is observed. The MOS capacitor is biased into strong inversion before applying the voltage ramp in order to eliminate surface generation. FromC-t transient curve obtained experimentally the minority carrier generation lifetime in semiconductor can be determined. The experimental results show that for the same sample the lifetimes extracted fromC-t curves under varying voltage sweep rates are close each other, and they are consistent with the lifetimes extracted by saturation capacitance method.     

Applications of fast atom bombardment mass spectrometry (FAB MS) to organometallic and coordination chemistry

This article describes the technique of fast atom bombardment mass spectrometry (FAB MS) and its applications to the analysis of organometallic and coordination complexes. Sections on ion generation and matrices are followed by a Periodic Group-based review of FAB MS results obtained from Transition Metal and Main Group compounds, organometallic cluster carbonyls and their derivatives, and salts of poly-oxo-anions. The literature has been surveyed from 1981 to approximately mid-1986.     

High resolution staring arrays answering compact MW and LW applications

This paper overviews the electro-optical and thermal performances of different types of infrared detectors manufactured by Sofradir. The detector’s fabrication processes and detector’s performance are shortly described. New staring arrays are more compact and offer system solutions required by infrared market. Special attention is directed to some reliability advantages of new dewar design. Finally, the development trends for highest resolution infrared detector are discussed. The paper presented there appears in Infrared Photoelectronics, edited by Antoni Rogalski, Eustace L. Dereniak, Fiodor F. Sizov, Proc. SPIE Vol. 5957, 59570U (2005).     

相干叠加态高次谐波发射的时间行为分析

本文研究了一维模型分子离子(初态为基态和一个激发束缚态叠加的相干态)在超强超短激光脉冲作用下的谐波发射谱.我们发现在高次谐波谱平台区域出现了周期性的结构变化.我们利用小波变换对谐波谱进行了暂态时间频率分析,结果表明该谐波结构产生的原因是由电离电子返回母离子时与不同束缚态复合而产生的谐波光脉冲之间相干叠加.同时采用半经典计算,对所得到的计算结果进行了分析,验证了我们的结论.     

Internet 防火墙及其发展趋势

本文叙述了Internet来自外部、内部、硬件、软件方面的十种安全威胁和攻击,给出了防火墙的限制、隔离、筛选、过滤和屏蔽作用,介绍了防火墙的六种基本结构类型,论述了过滤路由器、双宿主主机、主机过滤、过滤子网和吊带式五种安全结构,分析了传统防火墙的七种不足,给出了目前防火墙混合应用包过滤技术、代理服务技术和其他一些技术的发展趋势。     

红外动态图像生成技术概念研究

红外动态图像生成技术的基本概念包括基本术语及其定义。为了描述红外动态图像生成技术的特性,通常采用如光源类型、光谱波段、阵列规模、空间分辨率、填充因子、时间常数、帧频、闪烁、温度范围、串扰、均匀性、发射率、辐射对比度、动态范围、温度分辨率、调制传递函数、几何畸变及最大温度和最大辐射强度等概念。介绍了描述红外动态图像生成系统性能的基本概念的定义。转换器的指标定义对于转换器的设计和性能指标的测试都有重要的意义。     

一种高性能超宽带线性调频信号源

介绍一种VHF／UHF频段高性能超宽带线性调频信号源的设计与实现。首先简要阐述了高性能超宽带线性调频信号源的设计思想，然后依据基带数字产生结合倍频扩展带宽的思路提出了一种超宽带线性调频信号产生方案，并进行了设计实现研究。测试结果表明：按照本文阐述的指导思想和实现方案所设计的超宽带线性调频信号源达到 了相当高的性能。