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CRUSTAL STRUCTURE OF THE SOUTH CHINA SEA BASIN 总被引:2,自引:0,他引:2
Based on the results from prospcction of seismic sonobuoy and two-ship refraction measurement, structural characteristics for earth crust of South China Sea Basin are analyzed: very thick crustal Layer 1, normal crustal Layer 2 and abnormally thin crustal Layer 3 are observed, with Layer 3 increasing continuously in thickness towards NS direction from the centre of the basin, and the earth crust becoming thick accordingly. These structural characteristics are in conformity with Cenozoic sea spreading mode inferred from magnetic anomaly. Finally, possible causes that account for these characteristics are discussed. 相似文献
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追击问题是运动学中比较典型的问题,此类问题与实际联系紧密,涉及的知识较为综合,且与数学知识联系密切.曲线轨迹的"等速率追击"问题是此类问题中的一种.用不同方法研究其运动规律,逐层深入分析和讨论,可以拓宽学生的知识面,增加学生深层面的思维能力. 相似文献
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For preparing the phenobarbital(PHN) molecularly imprinted polymers(MIPs) with higher adsorption and selectivity properties, we used the M062 X/6-31 g(d,p) method of density functional theory to predict the various properties of PHN-MIPs. Here PHN is as the imprinted molecule and acrylamide(AM) as the functional monomer. The ethylene glycol dimethacrylate,trimethylolpropane trimethacrylate, divinyl benzene, and pentaerythritol trimethacrylate are as the cross-linking agents, respectively. The acetonitrile, chloroform, toluene, and tetrahydrofuran are used as the solvents, respectively. The configurations of the molecular imprinting self-assembly system for PHN and AM have been simulated to study their bonding sites, binding energy, amount of hydrogen bond, and interaction mechanism. The essence of imprinting interaction for PHN and AM has been revealed by the atomic in the molecule theory. Meanwhile, the analogues of PHN were used to discuss the selectivity property of the stable PHN-AM complex. The results show that the PHN interacts with AM through hydrogen bonds. When the imprinting molar ratio of PHN-AM is1:6 and the THF is as the solvent, the amount of their hydrogen bonds is the most, the binding energy is the lowest, and their configuration is the most stable. In comparison with the other cross-linking agents(EGDMA, TRIM, and DVB), the PETA is more suitable for PHN-MIPs. The selective property of PHN-MIP to PHN is excellent when PHN and DMBA exist at the same time. 相似文献
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质量为m的物体从地面上方h1高度自由下落到h2高度,物体的速度为v,由机械能守恒或动能定理易得表达式mgh1-mgh2=1/2mv2,然文献[1],作者通过详实的分析指出了这个看似严谨表达式的不严密之处,并通过系统的能量分析对表达式进行了修正,鉴于分析、讨论的需要,特将原文中的问题、部分分析摘录如下. 相似文献
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以密度泛函理论结合跳跃模型, 重点研究了氯原子和烷基链的引入对吲哚并咔唑类衍生物传输性质的影响. 计算结果表明, 与吲哚并[3,2-b]咔唑(1)相比, 氯原子的引入增大了2,8-二氯吲哚并[3,2-b]咔唑(2)和2,8-二氯-5,11-二己基吲哚并[3,2-b]咔唑(3)的最高占据分子轨道(HOMO)的离域程度, 而对最低未被占据分子轨道(LUMO)则无显著贡献, 但明显降低了二者的能级. 上述结果表明, 对于LUMO, 氯原子体现了吸电子效应, 而对于HOMO, 氯原子体现了共轭效应. 烷基链的引入使化合物3的空穴迁移率明显高于化合物1和2, 这主要归因于化合物3具有更加紧密的分子堆积, 尤其在跳跃路径A中, 具有更大的分子间电子耦合和轨道重叠. 同时能带结构的计算结果进一步证明, 氯原子和烷基链的同时引入大大改善了吲哚并咔唑类衍生物的电荷传输性能. 相似文献
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本文对文献[1]中的一个问题进行了理论与实验研究,指出了原有解释的不当之处,并采用基于Runge-Kutta-Felhberg算法的Matlab数值方法给出本问题的数值解. 相似文献
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