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51.
52.
着重研究了多孔介质BISQ模型中慢纵波的基本特性.给出了BISQ模型下慢纵波速度 和衰减的低频近似公式.与Biot理论对比,BISQ模型中慢纵波的衰减随频率降低急剧增大, 且随喷射流长度的减小而增加;相速度随喷射流长度的减小而增加,其低频极限值不是零; 孔隙流体位移与固相骨架位移之比的幅值随喷射流长度的增加而减小,其相位特点与Biot模 型预测的不同;在流体与孔隙介质的边界上可产生更大的渗流.为对比,同时也给出快纵波 的行为.依据BISQ模型可推断:非黏滞流体饱和孔隙介质中不存在喷射流机理;BISQ模型中
关键词:
多孔介质
喷射流
慢纵波
动力协调 相似文献
53.
54.
报导了采用基于室温脉冲量子级联激光器的脉内光谱检测技术,利用中心波长为1904 cm-1的量子级联激光器,在实验室对NO气体样品进行检测的研究结果. 针对单线直接吸收光谱反演算法进行了研究,介绍了基线拟合的最小二乘算法以获取其吸光度,根据HITRAN数据库中相应吸收谱线的吸收线强,采用扫描积分实现了气体浓度的反演,避免了标气标定造成的误差及污染;通过拟合残差分析得到了系统的检测限,达到34×10-6 m.
关键词:
量子级联激光器
中红外
多项式拟合
扫描积分 相似文献
55.
该文研究一个反应扩散方程组的自由边界问题,它来源于描述抑制物作用下无坏死核肿瘤生长的数学模型.作者运用抛物型方程的Lp理论和压缩映照原理,证明了这个问题局部解的存在唯一性,然后用延拓方法得到了整体解的存在唯一性. 相似文献
56.
在s波超导体绝缘层dx2-y2波超导体结(sId)中,考虑到结界面粗糙散射,运用BogoliubovdeGennes(BdG)方程和FurusakiTsukada(FT)电流公式,计算超导结中的准粒子传输系数和直流Josephson电流.结果表明:sId超导结的直流Josephson电流随温度以及结两侧的相位差变化的关系曲线强烈地依赖于d波超导体的晶轴方位;结界面的粗糙散射对Josephson电流有抑制作用
关键词:
s/I/d超导结
dx2-y2波超导体
直流Josephson电流 相似文献
57.
W. Chen X. L. Xu P. Zhou Y. M. Cui Y. G. Li 《Russian Journal of Coordination Chemistry》2013,39(3):301-304
Two silver(I) compounds, [Ag(R,R-hxn)](C7H4BrO2) · 2H2O (I) (Chxn = 1,2-diaminocyclohexane) and [Ag(C5H6N2)2]2(C8H4O4) · 10H2O (II), were synthesized and complex I was structurally characterized by X-ray crystallography. Compound I contains a catena-(trans-1,2-diaminocyclohexane) silver polycation ([Ag(Chxn)]∞) in a roughly linear fashion, while II possesses a linear-type silver monocation. Compounds I and II were evaluated for their inhibitory activities against Helicobacter pylori urease in vitro. Both were found to have strong inhibitory activities against H. pylori urease comparable to that of acetohydroxamic acid. 相似文献
58.
The 3D fluorescence discrimination of phytoplankton classes was investigated by SA4 multiwavelet,GHM multiwavelet,and coifman-2(coif2) wavelet analysis.Belonging to 35 genera of 7 major phytoplankton divisions in the inshore area of China Sea,Single species cultures of 51 phytoplankton species were employed.The second scale vector (Ca2) of SA4,Ca2 of GHM and the third scale vector (Ca3) of coif2 were selected as feature spectra by Bayesian discriminate analysis (BDA).The reference spectra were obtained via hierarchical cluster analysis (HCA).With average high correct discrimination ratios (CDRs),reference spectra were representative to phytoplankton species.For one-algae samples,the average CDRs were 95.6% at genus level and 86.7% at division level.For the laboratory mixed samples,the average CDRs (one division accounted for 25%,75% or 100% of the total biomass) were 86.6%,91.4% and 100% at division level.Moreover,the average CDRs of the dominant species (accounted for 75%) was 79.8% at genus level.Results for the in situ samples were coincided with the microscopic ones at division level with the relative contents of 54.3%-96.5%.The fluorometric discriminating technique was further tested during the cruise in Bohai Sea recently. 相似文献
59.
Cuiling Du Dr. Jie Zhao Dr. Jinbo Fei Dr. Liang Gao Wei Cui Dr. Yang Yang Prof. Dr. Junbai Li 《化学:亚洲杂志》2013,8(4):736-742
A reactive template method was used to fabricate alginate‐based hydrogel microcapsules. The uniform and well‐dispersed hydrogel capsules have a high drug loading capacity. After they are coated by a folate‐linked lipid mixture on the surface, the capsules possess higher cell uptake efficiency by the molecule recognition between folate and the folate‐receptor overexpressed by the cancer cells. Moreover, in this bioconjugate, the lipid could remarkably reduce the release rate of hydrophilic doxorubicin from the hydrogel microcapsules and encapsulate the hydrophobic photosensitizer hypocrellin B. The biointerfaced capsules could be used as drug carriers for combined treatment against cancer cell proliferation in vitro; this was much more effective than chemotherapy or photodynamic therapy alone. 相似文献
60.
Song Yun Weizhong Qian Chaojie Cui Yuntao Yu Chao Zheng Yi Liu Qiang Zhang Fei Wei 《Journal of Energy Chemistry》2013,22(4):567-572
For the synthesis of single-walled carbon nanotubes (SWCNTs) from CH4 over a Fe/MgO catalyst, we proposed a coupled Downer-turbulent fluidized-bed (TFB) reactor to enhance the selectivity and yield (or production rate) of SWCNTs. By controlling a very short catalyst residence time (1–3 s) in the Downer, only part of Fe oxides can be reduced to form Fe nano particles (NPs) available for the growth of SWCNTs. The percentage of unreduced Fe oxides increased and the yield of SWCNTs decreased accordingly with the increase of catalyst feeding rate in Downer. SWCNTs were preferentially grown on the catalyst surface and inhibited the sintering of the Fe crystallites which would be formed thereafter in the downstream TFB, evidenced by TEM, Raman and TGA. The coupled Downer-turbulent fluidized-bed reactor technology allowed higher selectivity and higher production rate of SWCNTs as compared to TFB alone. 相似文献