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991.
992.
以简易的量子化学方法计算了二十多种卤代苯和苯酚衍生物的FMO位电荷密度能 ,并进行定量结构—活性相关 (quantitativestructurebiodegradability)研究 ,获得满意的结果 .最后从生物酶促反应本质、污染物 -生物酶的轨道控制反应角度对QSAR提出新的解释 相似文献
993.
The calculation of the molecular electrostatic potential from simplified models of the electron density is considered. Results are shown for water, hydrogen fluoride and ammonia. Little loss of accuracy is evident when the density is represented by a linear sum of well-chosen Gaussians. When these are further simplified into sets of point charges the inner parts of the molecule are poorly represented. More elaborate point moments make the representation worse. On the other hand a mixed representation with point charges and one diffuse Gaussian gives all the essential features of the potential of these molecules. 相似文献
994.
采用密度泛函理论的B3LYP方法和二次组态相互作用(QCISD(T))方法优化计算了OH分子基态(X2Π)的平衡结构、振动频率和离解能.根据原子分子反应静力学原理,导出了OH分子基态(X2Π)的合理离解极限,采用最小二乘法拟合Murrell-Sorbie函数得到了相应的势能函数和与该基态相对应的光谱常数(Be,αe,ωe和ωeχe),计算结果与实验数据符合得相当好.
关键词:
OH分子
2Π)')" href="#">基态(X2Π)
势能函数 相似文献
995.
Snezana Savic Gordana Vuleta Rolf Daniels Christel C. Müller-Goymann 《Colloid and polymer science》2005,283(4):439-451
The aim of this study was to examine the lyotropic potential of an alkylpolyglucoside mixed emulsifier (Cetearyl glucoside&Cetearyl alcohol), which belongs to the new generation of natural (sugar) surfactants, and to elaborate the potential stabilization mechanism and relation between the colloid microstructure and water distribution within the systems. Polarization and ordinary light as well as transmission electron microscopy, wide and small-angle X-ray diffraction, thermal analysis and rheological measurement were employed for the systems characterization.It was suggested that Cetearyl glucoside&Cetearyl alcohol stabilizes the o/w creams by synergistic effects of viscoelastic hydrophilic gel of lamellar type and lipophilic gel network built up from cetostearyl alcohol semi-hydrates as well as by lamellar liquid crystalline bilayers surrounding the oil droplets. The hydrophilic gel consists of mixed cetearyl glucoside/cetearyl alcohol crystalline bilayers entrapping the water interlamellarly by hydrogen bonding. It is also showed that oil addition into the chosen binary system influences the creams microstructure significantly, which particularly reflects onto the mode of water distribution within the creams and consequently their potential of skin hydration. 相似文献
996.
997.
998.
Mousumi Ballav A. Roy Chowdhury 《Communications in Nonlinear Science & Numerical Simulation》2007,12(8):1440-1453
Properties of spatial solitons in channel waveguide and optical lattice are studied with the help of projection operator approach. The nonlinearity is assumed to be of cubic-quintic type. The stability consideration of the fixed point solutions of the ODE’s governing the evolution of soliton parameters indicates to the existence of more than one branch of soliton, giving rise to multistability. Explicit numerical analysis gives more information than the standard Vakhitov–Kolokov criterion. A systematic numerical simulation of the soliton profile gives detailed information about the nature of trapping and structure of the different branches of the pulse. It is observed that even under different launching conditions the solitons do not radiate but get trapped. 相似文献
999.
Potential Analysis - Assume that a bounded domain Ω??N (N ≥ 2) has the property that there exists a signed measure µ with compact support in Ω such that, for every... 相似文献
1000.