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11.
次声波武器及其物理基础   总被引:3,自引:1,他引:2  
王秀敏 《大学物理》1999,18(5):43-44
分析了两次声波武器的工作原理,并在此基础上对其主要特征加以简要分析。概述了次声波武器的发展现状。  相似文献   
12.
13.
The molecular mechanism of the binding of norfloxacin (NRF) to trypsin was investigated by fluorescence, synchronous fluorescence and UV–vis absorbance spectroscopy and molecular modeling at physiological conditions. The quenching mechanism and the binding mode were investigated in terms of the association constants and basic thermodynamic parameters. The results of spectroscopic measurements suggested that NRF have a strong ability to quench the intrinsic fluorescence of trypsin through static quenching procedure. Moreover, fluorescence experiments were also performed at different values of pH to elucidate the effect of pH on the binding. The NRF–trypsin complex was stabilized by hydrophobic forces and hydrogen bonding, via tryptophan residue as indicated from the thermodynamic parameters, which was consistent with the results of molecular docking and accessible surface area calculations.  相似文献   
14.
可调光瞳滤波器的轴向焦移及扩展焦深   总被引:2,自引:1,他引:1  
光学超分辨、焦深扩展及焦移3种效应一直受到研究人员的关注,且在光学显微成像、光学校准、光学相干层析成像及光存储中有着重要的应用.提出一种可调谐光瞳滤波器来实现光学系统的轴向焦移及扩展焦深.该光瞳滤波器由两个完全相同且相互平行的λ/4波片和置于其间的λ/2波片组成,其中λ/2波片分为两个可作相对旋转的区域,并且通过推导得...  相似文献   
15.
新型自然循环自动清洗式蒸发器及设计原理   总被引:1,自引:0,他引:1  
以高效蒸发器为目标,旨在以自然循环替代高能耗的强制循环泵、以自动清洗取代加热面盐垢的周期性停车清洗.主要研究沸腾室内的不平衡汽化过程机理,提出动力温度的新概念,采用显热与汽化热转换平衡的研究方法,得到自然循环推动力的工程设计计算式,并且由此引出推动力强化的基本原则,进而获得中试的成功.还提出加热室必须采用能够低流速下自转清洗又高效传热强化的螺旋齿带,才能保障循环总阻力低于推动力.  相似文献   
16.
A multiplex polymerase chain reaction (m-PCR) assay was developed for the simultaneous detection of multiple components of genetically modified (GM) soybean. It uses two sets of primers (I, lectin1/35S/CP4; II, lectin2/35S/CP4) specific for a soybean reference gene, the 35S promoter, and an event-specific gene. Amplified fragments of 118, 414, 195, and 320 bp were easily detected by agarose gel electrophoresis and were positively confirmed by sequencing. Primer set concentrations and annealing temperatures in the m-PCR were optimized. The optimized m-PCR conditions were obtained for primer set I at a ratio of 1:2:3 and a 59.2 °C annealing temperature and set II at the same ratio and 58.6 °C, 60.3 °C, and 61.2 °C annealing temperatures. The sensitivities of the two m-PCR primer sets (I and II) were 0.25% and 0.5%, respectively. The results showed that this m-PCR assay provides rapid, reliable, and effective identification of multiple components of GM soybean in feed.  相似文献   
17.
A novel strategy was utilized to develop a stable probe based on thiolated poly(ethylene glycol) (SH-PEG) and polyacrylic acid (PAA) functionalized gold nanorods (GNRs), following the attachment of an anti-cancer drug, doxorubicin (DOX), to obtain PAA-PEG-GNRs@DOX assemblies. Importantly, the obtained probe as a novel drug-delivery and fluorescent imaging agent for simultaneous imaging of and drug delivery to prostate cancer cells has also been demonstrated. In addition to designing PAA-PEG-GNRs that passively target tumor cells for cancer-fighting drug therapy, GNRs are also regarded as hyperthermia agents for photokilling cancer cells, so that the tumor would be attacked on two fronts simultaneously.  相似文献   
18.
Jinsong Li  Xiumin Gao  Songlin Zhuang 《Optik》2008,119(14):671-681
In this article, a nonspiral plate is investigated numerically by vector diffraction theory to observe the focusing properties of Gaussian beams. Both low- and high-numerical-aperture (NA) optical systems are considered in the investigation. It is found that the parameter of NA and the phase vary rate of the phase plate influence the focal intensity distribution considerably. When a nonspiral plate is used to provide linear phase variation on one half of the Gaussian beam, it may adjust the focal spot considerably and conveniently. Changing the vary rate of the phase plate or the parameter of NA can alter optical intensity distribution; some novel focal spots and focal switch may also occur.  相似文献   
19.
激光-钨靶耦合效应的二维模拟研究   总被引:1,自引:0,他引:1  
利用二维ESCL-CASTOR磁流体力学三温激光靶程序,对激光-钨靶进行了计算机模拟研究。得到了密度、温度(T_e,T_i,T_R)和速度的空间分布以及随时间的变化规律;特别是得到了临界面的运动规律、辐射谱和X光转换效率等结果,并与实验结果进行了比较。  相似文献   
20.
通过复势函数计算出了同轴圆弧柱形电容器及非平行板电容器的电容、场强和薄金属弧片中的电导、电势.  相似文献   
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