Approximate Symmetry Reduction and Infinite Series Solutions to the Nonlinear Wave Equation with Damping

The approximate symmetry perturbation method is applied to the nonlinear damped wave equation. The approximate symmetry reduction equations of different orders are derived and the corresponding series reduction solutions are obtained.     

New variable separation solutions for the generalized nonlinear diffusion equations

The functionally generalized variable separation of the generalized nonlinear diffusion equations ut = A(u, ux)uxx +B(u, ux) is studied by using the conditional Lie–Ba¨cklund symmetry method. The variant forms of the considered equations,which admit the corresponding conditional Lie–Ba¨cklund symmetries, are characterized. To construct functionally generalized separable solutions, several concrete examples defined on the exponential and trigonometric invariant subspaces are provided.     

Kinetic effect in the size-control of CdS nanoparticles

A new method of size control for CdS nanoparticles, called common cation coprecipitation, is reported. In the course of coprecipitation, both CdS and CdSt_2(cadmium stearate) formations are diffusion-controlled and their rates are quite different. The size of CdS nanoparticles depends on the ratio of initial concentrations of S~(2-) to St~- (stearate ion). Characterized by UV-Vis absorption, XRD, TEM, fluorescence and XPS, the results obtained show that the coprecipitate is a composite, i. e. CdS particle inserts in the CdSt_2 molecular layers to form a sandwich-like structure. The method reported for size control of CdS nanoparticles might be called kinetic self-assembling.     

一类环丙烷螺环化合物的简易合成和结构表征

以乙二醇二甲醚为溶剂,在K2CO3及痕量水存在下,鉮盐和多取代贫电子烯烃反应,高立体选择性合成了顺-1-甲氧羰基-2-取代芳基-6-环己烷基-5,7-二氧杂螺-〔2,3〕-4,8-二酮。采用IR、MS、1H NMR、13C NMR、DEPT及二维核磁共振技术对所合成的化合物进行了结构表征,并以NOESY实验确定了该化合物为顺式结构的环丙烷衍生物。     

Functional Variable Separation for Extended （l＋2）-Dimensional Nonlinear Wave Equations

The functional variable separation approach is applied to study extended （1＋2）-dimensional nonlinear wave equations. Complete classification for those equations admitting the functional separable solutions and some exact separable solutions are obtained.     

还原蓝RSN在染色中过还原问题的研究

讨论了还原蓝RSN在染色过程中过还原及其控制的原理。通过实验 ,优选出了能有效防止还原蓝RSN发生过还原现象的染色工艺条件。     

Reason for the loss of hydrophilicity of TiO_2 film and its photocatalytic regeneration

TiO2 film was prepared on soda-lime glass by sol-gel method. The water contact angle (θ) of the fresh TiO2 film is 0°. During storage in air, the surface of TiO2 film is gradually converted to the hydrophobic state. XPS and ITD results reveal that it is due to the adsorption of organic contaminants on TiO2 surface in air ambience. The lost hydrophilicity of TiO2 film can be regenerated by UV illumination.     

Initial-value Problems for Extended KdV-Burgers Equations via Generalized Conditional Symmetries

We classify initial-value problems for extended KdV-Burgers equations via generalized conditional symmetries. These equations can be reduced to Cauchy problems for some systems of first-order ordinary differential equations. The obtained reductions cannot be derived within the framework of the standard Lie approach.