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141.
Using improved homogeneous balance method, we obtain complex function form new exact solutions for the (1+1)-dimensional dispersion-less system, and from the exact solutions we derive real function form solution of the field u. Based on this real function form solution, we find some new interesting coherent structures by selecting arbitrary functions appropriately.  相似文献   
142.
The generalized transformation method is utilized to solve three-dimensional Nizhnik-Novikov-Veselov equation and construct a series of new exact solutions including kink-shaped and bell-shaped soliton solutions, trigonometric function solutions, and Jacobi elliptic doubly periodic solutions. Among them, the Jacobi elliptic periodic wave solutions exactly degenerate to the soliton solutions at a certain limit condition. Compared with the existing tanh methods and Jacobi function method, the method we used here gives more general exact solutions without much extra effort.  相似文献   
143.
管清梅  杨忠志 《中国化学》2007,25(6):727-735
A detailed theoretical investigation on Co^3+ hydration in aqueous solution has been carded out by means of molecular dynamics (MD) simulations based on the atom-bond electronegativity equalization method fused into molecular mechanics (ABEEM/MM). The effective Co^3+ ion-water potential has been constructed by fitting to ab initio structures and binding energies for ionic clusters. And then the ion-water interaction potential was applied in combination with the ABEEM-7P water model to molecular dynamics simulations of single Co^3+(aq.) solution, managing to reproduce many experimental structural and dynamical properties of the solution. Here, not only the common properties (radial distribution function, angular distribution function and solvation energy) obtained for Co^3+ in ABEEM-7P water solution were in good agreement with those from the experimental methods and other molecular dynamics simulations but also very interesting properties of charge distributions, geometries of water molecules, hydrogen bond, diffusion coefficients, vibrational spectra are investigated by ABEEM/MM model.  相似文献   
144.
ArH+势能曲线的从头计算   总被引:1,自引:0,他引:1  
ArnH^ 是非常重要而又较简单的簇体系,对于它们的深入研究,有助于人们认识质子在溶液中的溶剂化行为,该簇中最为简单而又重要的存在形式是ArH^ 和ArnH^ 。ArH^ 可以在气相中稳定存在,在所有的ArnH^ 族中被研究得最早,实验数据也最为齐全,人们对ArH^ 体系进行了许多理论计算,但只局限于平衡键长、简正振动频率、解离能等分子参数,计算结果与已知的振动-转动光谱数据基本符合。  相似文献   
145.
通过石墨炉原子吸收法破膜检测胞内Rb+的含量, 考察大环配体缬氨霉素运载Rb+跨膜的行为. 基于传输过程的动力学研究, 讨论了离子跨细胞膜时影响离子传输速率和跨膜量的各种因素. 同时还以荧光法研究了RbCl对红细胞膜蛋白荧光强度的作用. 结果显示, 缬氨霉素传输Rb+跨人红细胞膜的行为呈现串联一级反应动力学特征, 跨膜量主要受配体浓度、温育时间的影响. 高浓度RbCl能够影响膜蛋白的荧光强度.  相似文献   
146.
化甲烷催化剂的可能性. 在B3LYP/6-311++G(3df,3p)和MP2/6-311++G(3df,3p)水平下优化了反应通道上各驻点(反应物、中间体、过渡态和产物)的几何构型. 在G2M(+)水平下计算了各物种的能量. 研究结果表明: CH4与Br+(3P)反应存在三条不同的吸热反应途径, 与Br+(1D)反应存在二条不同的放热反应通道. 反应更易于通过单重态反应通道进行. 理论结果不仅较好地解释了实验事实, 还说明Br+有可能成为一种活化甲烷的催化剂.  相似文献   
147.
采用简单的液相法合成了SiO2/LaF3:Eu3+核壳结构发光粒子, 并对其结构及发光性能进行了表征. XRD分析表明包覆层LaF3:Eu3+为立方晶相结构, 红外光谱表明SiO2颗粒表面有柠檬酸的修饰, 电镜照片表明合成了球形的核-壳结构的复合粒子, 包覆层厚度为10~20 nm, 光谱测试表明核-壳复合粒子与纯的LaF3:Eu3+具有相同的发光性能, 均以589 nm附近的5D0—7F1磁偶极跃迁为最强发射峰, 说明Eu3+在LaF3基质中占据的格位相同.  相似文献   
148.
用常规合成方法制备了基于Anderson结构阴离子的二维层状化合物[(C6n5NO2)Pr(H2O)4](CrMo6O24H6)·(C6H5NO2)·2.5H2O,通过红外光谱和X射线单晶衍射对其进行了表征.结果表明,该化合物属于单斜晶系,C2/c空间群.a=2.3442(9)nm,b=1.3291(5)nm,c=2.458(1)nm,β=103.08(1)°,V=7.460(5)nm^3,R1=0.0727,wR2=0.1903.结构分析表明,[CrMo6O24H6]^3-阴离子通过端氧担载一个配位的Pr^3+离子形成中性的(C6H5NO2)Pr(H2O)4(CrMo6O24H6)基团,相邻的中性基团在O1-Pr-O1桥联下形成一维链,链与链又通过异烟酸的桥联形成二维层状结构.  相似文献   
149.
A new polymer [Zn2(cam)2(bpmp)]n 1 (H2cam = D-(+)-camphoric acid, bpmp = bis(4-pyridylmethyl)piperazine) was synthesized under hydrothermal conditions. The compound crystallizes in the monoclinic system, space group P21/n with a = 12.305(9), b = 12.945(9), c = 13.619(10) A, β = 116.833(8)°, V= 1936(2)A3, Z = 4, Mr = 397.76, Dc= 1.365 Mg/m3,μ = 1.292 mm-1, F(000) = 832, the final R = 0.0578 and wR = 0.1678 for 2838 observed reflections with I 〉 2σ(I). The compound presents a three-dimensional (3D) network extended by homochiral 2D layer and bpmp ligands. From the topology point of view, the structure could be described as a 3D 6-connected mab net with (44.610.8) topology. In addition, infrared spectroscopy, elemental analyses, thermogravimetric analysis and powder X-ray diffraction properties of 1 are also investigated.  相似文献   
150.
With the help of an improved mapping approach and a linear-variable-separation approach, a new family of exact solutions with arbitrary functions of the (2+1)-dimensional Nizhnik-Novikov-Veselov system (NNV) is derived. Based on the derived solutions and using some multi-valued functions, we find a few new folded solitary wave excitations for the (2+1)-dimensional NNV system.  相似文献   
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