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A Method of Measuring the In Situ Seafloor Sound Speed using Two Receivers with WarDing Transformation 下载免费PDF全文
We present a method of measuring the in situ superficial seafloor sound speed by using two receivers deployed vertically in sediment, based on the dispersion characteristic of normal modes in shallow water. Warping transfor- mation is adopted to extract the first normal mode from the broadband propagation signals. Some experimental results which could validate the method are shown. One of the advantages of the method is that the seafloor sound speed can be solved directly from the relative vertical transmission loss of the first normal mode without the exact priori information of the environmental parameters such as the sound speed profile, the water-column depth and the source location. 相似文献
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在亚洲海国际声学实验(ASIAEX2001)中记录了本地混响和异地混响的实验数据。对数据进行处理时,发现异地混响数据和本地混响数据有较大差异:本地混响衰减和混响垂直相关小于异地混响衰减和垂直相关。为了解释这一现象,根据浅海混响的射线简正波理论,结合三维海底散射模型,给出了浅海异地混响衰减和混响垂直相关的一般表达式。讨论了与本地混响衰减和混响垂直相关的关系,并与实验数据进行了比较。理论计算和实验数据表明:在经过时延(从声源到接收器的传播时间)后,较远距离的异地混响衰减与混响垂直相关可以由本地混响衰减和垂直相关近似表示。 相似文献
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本文合成、表征了乙二胺、1,3-丙二胺和1,2-丙二胺桥联邻菲咯啉配体及其镧(Ⅲ)配合物,研究了配合物对人白血病HL60、人前列腺癌PC-3MIE8、人胃癌BGC-823、人乳腺癌MDA-MB-435、人肝癌Bel-7402、人宫颈癌Hela等6个瘤株的体外抗肿瘤活性及其与DNA的作用方式,结果表明该系列化合物对实验的6种瘤株均具有明显的生长抑制作用,具有广谱性。其作用机理可能是配合物以部分插入方式,同时伴随共价作用与静电作用与DNA发生作用,进而影响基因调控与表达,抑制肿瘤细胞的生长,最终导致癌细胞的凋亡。 相似文献
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Bistatic and monostatic reverberation data were recorded in the 2001 Asian Sea International Acoustic Experiment (ASLIAEX).A model based on the normal mode theory has been developed to calculate bistatic bottom reverberation in shallow water and to explain the recorded data.The comparisons between the monostatic and bistatic reverberation data are discussed,and the comparisons between model predictions and measured bistatic reverberation data are also presented.The numerical and experimental results show that the numerical predictions from the bistatic reverberation model fit the experimental data well,and the long-range bistatic reverberation with a time delay can be approximately expressed by the monostatic reverberation data. 相似文献
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1 INTRODUCTION The use of transition metal catalysts with nitro- gen-donor ligands is expanding rapidly[1], and the most widely used nitrogen ligand is the bidentate 2, 2?bipyridine unit[2]. Copper is found to be especial- ly important in the nervous sy… 相似文献
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二胺桥联邻菲罗啉衍生物的合成及其与DNA相互作用研究 总被引:8,自引:0,他引:8
A new ligand N,N′-bis(2-methelene-1,10-phenanthroline)-3,6-dioxa-1,8-octaneethylenediamine(L) and the corresponding complexes LaL, LaL(Phe), and LaL(Try) were synthesized. The interaction of the complexes with calf thymus DNA was studied by means of electronic absorbance spectra, flurescence spectra, circular dichroic spectra and viscosity experiments. All the results indicate that the complexes may interact mainly with calf thymus DNA by intercalation and coordination binding. 相似文献
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Horizontal correlation is one of the most important characteristic parameters in ocean acoustics. In a shallow water acoustic experiment, we observed that the transverse correlation coemcient is an oscillation function of frequency. A model based on adiabatic normal mode theory in a random inhomogeneous waveguide which is statistically isotropic in a horizontal plane is developed. The theory indicates that the oscillation of the transverse correlation coefficient is mainly due to the normal mode interference. 相似文献