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201.
LIU Ping LOU Sen-Yue 《理论物理通讯》2009,51(1):27-34
The symmetries, symmetry reductions, and exact solutions of a coupled nonlinear Schrodinger (CNLS) equation derived from the governing system for atmospheric gravity waves are researched by means of classical Lie group approach in this paper. Calculation shows the CNLS equation is invariant under some Galilean transformations, scaling transformations, phase shifts, and space-time translations. Some ordinary differential equations are derived from the CNLS equation. Several exact solutions including envelope cnoidal waves, solitary waves and trigonometric function solutions for the CNLS equation are also obtained by making use of symmetries. 相似文献
202.
基于单、双链DNA与纳米金颗粒间的不同静电作用, 建立了一种基于颜色反应检测NOS1AP基因单碱基突变的方法. 根据NOS1AP基因的单碱基多态位点设计检测探针、互补靶序列及带有单碱基突变序列寡核苷酸DNA. 室温下, 检测探针分别与互补序列、单碱基突变序列在缓冲液中进行杂交, 再分别加入纳米金溶液以及NaCl溶液. 用肉眼可以观察到纳米金溶液在两种不同杂交溶液中产生明显不同的颜色变化. 这种变化可通过紫外-可见分光光度计测定纳米金溶液的紫外吸收峰值的变化来证实. 实验结果表明, 纳米金溶液在一定浓度NaCl存在的条件下, 对互补双链NOS1AP DNA及单碱基突变NOS1AP DNA呈现出不同的颜色反应及紫外吸收光谱的改变. 此方法可望用于相关疾病的医学诊断及单碱基突变的检测. 相似文献
203.
LOU Sen-Yue 《理论物理通讯》2001,(11)
Taking the well known (1- l)-dimensional turbulence system,the Korteweg de-Vries Burgers equation,as a special example,we show that some types of lower-dimensional turbulence systems may be derived from some higherdimensional Lax integrable models,say,the (2 1)-dimensional asymmetric Nizhnik-Novikov-Veselov equation.On the other hand,using the Lax pair of the original higher-dimensional integrable model(s),we may obtain higher-dimensional Lax pair(s) for a lower-dimensional turbulence system.`` 相似文献
204.
LOUSen-Yue 《理论物理通讯》2001,35(5):589-592
Usually,one considers only the group velocity dispersion(GVD)-and self-phase modulation(SPM)-induced solitons in optic soliton communication while other higher order effects such as the third-order dispersion(TOD),self-steepening(SS),and stimulated Raman scattering are considered only perturbatively,In this paper,we study the existence of the TOD-and SS-induced soliton solutions.The existence conditions of the TOD-and SS-induced bright and dark solitons are quite different from those of the GVD-and SPM-induced solitons. 相似文献
205.
Conditional Similarity Solutions of the Boussinesq Equation 总被引:2,自引:0,他引:2
The direct method proposed by Clarkson and Kruskal is modified to obtain some conditional similarity solutions of a nonlinear physics model.Taking the (1 1)-dimensional Boussinesq equation as a simple example,six types of conditional similarity reductions are obtained. 相似文献
206.
207.
The homobinuclear complexes of Cu (Ⅱ) and Ni (Ⅱ) with N, N'-bis(3-Carboxyl salicyl aminal ethylene) oxalamide were synthesized, and characterized by elemental analysis, IR spectra, Uv-visible spectra, conductometry, thermogravimetry, and magnetic susceptibility measurement, which indicated the complexes own an oxalic amide bridge-linking structure. Room temperature magnetic moment data show that there are antiferromagnetic spin coupling through oxalic amide conjugated double bond, In DMF, the redox half wave potential of Cu (Ⅱ) binuclear complexes have been measured by cyclic voltammetry, which proves that the Cu (Ⅱ) complex has two redox waves. 相似文献
208.
The states of water in sodium bis(2-ethylhexyl) sulfosuccinate (AOT)/isooctane/water reverse(W/O) microemulsions system have been investigated by using Fourier transform infrared spectroscopy(FT-IR) technique. The broad peak obtained for hydroxy(O-H) of water has been resolved by least square curve-fitting. It has been observed that the water solubilized in microemul-sion droplets has four states, i.e. bound water with sulfo-group, free water, bound water with sodium counterion in the water pool of microemulsion droplets and a small amount of trapped water in the palisade layer of microemulsion droplets. The following have also been determined: the aggregation number (n), the radius of the water pool in the microemulsions(rw), the thickness of the bound water with sulfo-group(d1), the thickness of the bound water with sodium counterion(d2), the total thickness of the bound water (d) and the effective area of head groups of AOT(AAOT). 相似文献
209.
本文考察了四烷基澳化铵(TAAB)碳氢链长对离子型表面活性剂SDS和DTAB在气/液表面吸附行为的影响.实验结果表明,与表面活性剂离子对应的添加剂反离子是影响其水溶液表面活性的主要因素,因而TAAB对SDS表现出明显的效应,对DTAB影响效果则和同浓度的NaBr类似.除了对表面活性离子头基电荷的静电屏蔽外,TAA+的碳氢基团和SD-碳氢链间还可能发生疏水相互作用,但后者受TAA+离子体积制约.TAAB对SDS在气/液表面吸附行为的影响是上述几个因素的综合作用结果. 相似文献
210.
铝对人类智能的损害及其对策的研究 总被引:15,自引:1,他引:14
论述了铝对人类智能的影响。铝的来源主要包括环境铝,食物性铝,炊具中的铝和药源性铝。铝对人类智能危害的基本原理是铝可进入大脑,与脑神经结合形成脑组织神经原纤维缠结和老年斑。防治的方法是减少污染,及时应用铝络合剂排出体内的铝。 相似文献