小间隙高放大多丝室及其放电机制

对以强猝灭气体工作的小间隙多丝室及其放电机制进行了研究,实验表明,因为工作在饱和模式区,这种室同时具有很高的气体放大和相当快的时间特性.文中探讨了放电机制,雪崩中空间电荷效应以及电离光子的产生和作用是重要的因素,而其中后一因素又受到强猝灭气体的抑制.     

控温相变免疫分析测定雌酮

通过热引发聚合与氧化还原引发聚合，合成水凝胶，作为雌酮全抗原(E1— BSA)载体；以异硫氰基灾光素标记雌酮的单克隆抗体(McAb)作为示踪剂，建立了控温相变竞争免疫分析测定雌酮(EI)的方法并应用于分析血清样品。实验表明：以热引发聚合合成的水凝胶为载体的荧光免疫分析方法具有更高的灵敏度，它的线性范围为10-700μg/L，检出限为1μg／L(n=10，3倍空白)。经水凝胶性质的比较(包括LCST、非特异性吸附、抗原与抗体反应时间及固定化抗原活性)，证明了热引发聚合的水凝胶较氧化还原引发聚合的水凝胶更适合于作为免疫分析的载体。     

X波段五腔渡越管振荡器的理论与实验研究

 提出了一种新结构的X波段五腔渡越管振荡器，进行了理论和实验研究。根据场分布进行了一维非线性分析，结果表明该结构可以产生高功率微波，并判断了工作模式，为TM₀₁模的3π/5模。采用粒子模拟验证了一维非线性分析的结论，并优化设计出五腔渡越管振荡器,优化结果为：输出功率约1 GW， 工作频率9.3 GHz，束波转换效率约22%。实验中，通过参数调节，得到频率约9.25 GHz，峰值功率约780 MW，脉宽（半高宽）21 ns的输出微波，束波转换效率约为16%。实验结果与模拟结果基本符合。     

Triterpenoid Constituents of Huperzia miyoshiana

Thirteen triterpenoids, including three new ones, miyoshianois A (1), B (2) and C (3), were isolated from Huperzia miyoshiana. The structures of these new compounds were established as 3-O-dihydroferuloyltohogenol (1), 16-oxo-3β,21β-dihydrox-y-serrat-14-en-24-ferulate (2) and 16-oxo-3a, 21β-dihydroxy-serrat-14-en-24-ferulate (3), respectively, on the basis of their spectroscopic analysis.     

更新时间概率模型及其无偏估计定理的论证

本文提出应用小参数法 ,探讨 Markov链中相邻两次更新时刻内稀疏事件的概率估计问题 .建立了三种最重要的具有更新时间的概率模型 .通过小参数的引入和对概率式的幂展开 ,进而推证出幂渐近展开系数的模型估算法 .论证了无偏估计的重要定理 ,给出了概率估计式和无偏估计精度 .亦将许多算法扩展到Markov链的任意状态空间     

The spectrum of cyclic BSA(ν, 3, λ; α) with α = 2, 3

Balanced sampling plans excluding contiguous units (or BSEC) were first introduced by Hedayat, Rao, and Stufken in 1988. In this paper, we generalize the concept of a cyclic BSEC to a cyclic balanced sampling plan to avoid the selection of adjacent units (or CBSA for short) and use Langford and extended Langford sequences to construct a cyclic BSA(ν, 3, λ; α) with α = 2, 3. We finally establish the necessary and sufficient conditions for the existence of a cyclic BSA(ν, 3, λ; α) where α = 2, 3. © 2005 Wiley Periodicals, Inc. J Combin Designs.     

短脉冲激光尾流场中的前向Raman散射

用212维粒子模拟分析了前向Raman散射对激光尾流场加速电子的影响.前向Raman散射使脉冲长度在传播方向上被拉长，脉冲后沿变陡，产生的尾流场相速度明显减小，而且超热电子的最大动能明显小于理论估计值.此外激光频率整体向低频移动.     

Optical characterization of CdTe/ZnSe fractional monolayer structures grown by atomic layer epitaxy

Luminescence properties of CdTe/ZnSe fractional monolayer grown by atomic layer epitaxy have been investigated. To investigate the origin of the highly efficient luminescence, various optical spectroscopic methods such as, photoluminescence (PL), temporal/spatial resolved PL, temperature dependence PL, and excitation power dependence PL have been used. It is found that structural inhomogeneities affect dominant influence on the line width and line shape of luminescence. The luminescence intensity greatly enhanced by the localization of exciton at the disorder induced localized states.     

Synthesis,and Antimycobacterial and Cytotoxic Evaluation of Certain Fluoroquinolone Derivatives

Certain 1‐ethyl‐ and 1‐aryl‐6‐fluoro‐1,4‐dihydroquinol‐4‐one derivatives were synthesized and evaluated for antimycobacterial and cytotoxic activities. Preliminary results indicated that, for 1‐aryl‐6‐fluoroquinolones, both 7‐(piperazin‐1‐yl)‐ and 7‐(4‐methylpiperazin‐1‐yl) derivatives, 9b and 11a , are able to completely inhibit the growth of M. tuberculosis at a concentration of 6.25 μg/ml, while the 7‐[4‐(2‐oxo‐2‐phenylethyl)piperazin‐1‐yl] derivative 13 exhibits only 31% growth inhibition at the same concentration. For 1‐ethyl‐6‐fluoroquinolones, both 7‐[4‐(2‐oxopropyl)piperazin‐1‐yl]‐ and 7‐[4‐(2‐oxo‐2‐phenylethyl)piperazin‐1‐yl]‐derivatives, 2a and 2b , respectively, show complete inhibition, while their 2‐iminoethyl and substituted phenyl counterparts 3a and 2c are less active. In addition, the 6,8‐difluoro derivative was a more‐favorable inhibitor than its 6‐fluoro counterpart ( 2b vs. 2d ). These results deserve full attention especially because 2a, 2b, 9b , and 11a are non‐cytotoxic at a concentration of 100 μM . Furthermore, compound 9b proved to be a potent anti‐TB agent with selective index (SI)>40 and an EC₉₀ value of 5.75 μg/ml.