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芳香胺参加的Mannich反应——3-芳氨基-3-苯基-1-(4-溴苯基)丙酮的合成 总被引:2,自引:0,他引:2
文献报道过芳香胺与苯甲醛生成的Schiff碱可在少量相应的芳香胺盐酸盐或浓盐酸催化下制备Mannich碱(Ⅰ),所用的Schiff碱系事先合成,且产率较低(15-68.9%)。本文报导用4-溴苯乙酮、苯甲醛和芳香胺在少量浓盐酸催化下能直接发生Mannich反应, 相似文献
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By means of the renormalized vertex procedure for the motion Green's function developed by the au-thors, the vertex function of magnetic alloys, based on the s-d exchange interaction, is solved exactly and the corresponding Hall conductivity tensors are obtained. It is found that the renormalized modification of the conductivity is very important in the cases of not too weak extermal magnetic field and slow relexaction time. 相似文献
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利用推广的Hansch-Mahan量子输运方程,求解了分形子-电子相互作用系统的电阻率。克服了电阻率的低温发散困难,给出了电阻率反常处的温度。 相似文献
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Electronic structures and thermoelectric properties of solid solutions CuGa_(1-x) In_xTe_2 : A first-principles study
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The electronic structures of solid solutions CuGal_xlnxTe2 are systematically investigated using the full-potential all-electron linearized augmented plane wave method. The calculated lattice parameters almost linearly increase with the increase of the In composition, which are in good agreement with the available experimental results. The calculated band structures with the modified Becke-Johnson potential show that all solid solutions are direct gap conductors. The band gap decreases linearly with In composition increasing. Based on the electronic structure calculated, we investigate the thermoelectric properties by the semi-classical Boltzmann transport theory. The results suggest that when Ga is replaced by In, the bipolar effect of Seebeck coefficient S becomes very obvious. The Seebeck coefficient even changes its sign from positive to negative for p-type doping at low carrier concentrations. The optimal p-type doping concentrations have been estimated based on the predicted maximum values of the power factor divided by the scattering time. 相似文献
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设Sing_n是[n]上的奇异变换半群,得了变换半群M_n={α∈Sing_n:max{|xα~(-1)}≥|im(α)|(x∈im{α))}的主因子的极大正则子半群的完全分类. 相似文献
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线性聚焦和线性散焦效应对空间光孤子间相互作用的影响 总被引:2,自引:2,他引:0
考虑非均匀一维自聚焦介质的横向不均匀性,利用非线性薛定谔方程满足的守恒律给出了相邻空间孤子间隔的解析式,并对空间孤子之间的相互作用进行了数值模拟.结果表明,线形聚焦效应增强了空间孤子之间的相互作用;而线形散焦效应减弱了空间孤子之间的相互作用.当不考虑介质横向不均匀时,空间孤子之间发生周期性的碰撞.线性散焦效应使相邻空间孤子之间的间隔随传输距离发生周期性的变化,但孤子之间并不发生碰撞.线性聚焦效应使相邻空间孤子随传输距离发生周期性的碰撞,线性聚焦效应具有压制损耗使相邻空间孤子间隔变大的作用. 相似文献