Broer-Kaup系统的达布变换和新的精确解

利用Broer-Kaup系统Lax对的两个基本解，构造了该系统一个新的达布变换，并利用该变换求出了Broer-Kaup系统一组新的双向孤子解. 关键词： Lax对 达布变换 孤子解     

非线性耦合SchrOdinger-KdV方程组新的精确解析解

利用一类耦合Riccati方程组的某些特解构造了非线性耦合SchrdingerKdV方程组一批精确解析解,获得了该方程组若干形式一般的精确解及两组新的孤波解 关键词： 孤波解 Schrdinger-KdV方程组 符号计算     

系统动力学方法在规划研究中的应用——大连市种植业系统动力学模型的研究

本文运用系统动力学方法,对大连种植业系统进行了定性分析,建立了定量模型——系统动力学模型,对该市的种植业生产进行了动态建模、仿真和预测。为大连市种植业发展“八五”计划及十年规划的制定提供了科学依据。     

一类具不变性质的变系数偏微分方程的特解

In this paper, a few properties of general patial differential operator P beinginvariant with respect to the form F(|x|_p^p+|y|_q^q-|z|_r^r) are studied, where x∈Rⁿ,y∈ R^m, z∈R^l.and explicit formulas are given for certain solution of the equation Pu=Aδ with P being a differential operator with power function coefficientswhich preserves the form (|x|_p^p+|y|_q^q-|z|_r^r)^1/v for arbitrary even integers p, q, r,and odd integers v.     

考虑温度效应的泡沫铝准静态压缩本构模型

采用MTS材料试验机研究了不同密度(0.322~0.726g/cm~3)的闭孔泡沫铝在温度范围25~500℃下的准静态压缩力学性能,得到了泡沫铝在不同温度下的单轴压缩应力-应变曲线,分析了密度以及温度对其力学行为的影响。利用Liu和Subhash提出的本构模型对不同密度泡沫铝的应力-应变曲线进行拟合,分析并确定了模型中各参数随密度变化的函数,再代入Liu-Subhash模型,得到了泡沫铝的准静态压缩本构模型。通过引入温度软化项对准静态压缩本构模型进行修正,建立了考虑温度效应的泡沫铝准静态压缩本构模型,对闭孔泡沫铝的工程应用具有指导意义。     

Analytic Approximations for Soliton Solutions of Short-Wave Models for Camassa-Holm and Degasperis-Procesi Equations

In this paper, the short-wave model equations are investigated, which are associated with the Camassa- Holm （CH） and Degasperis Procesi （DP） shallow-water wave equations. Firstly, by means of the transformation of the independent variables and the travelling wave transformation, the partial differential equation is reduced to an ordinary differential equation. Secondly, the equation is solved by homotopy analysis method. Lastly, by the transformatioas back to the original independent variables, the solution of the original partial differential equation is obtained. The two types of solutions of the short-wave models are obtained in parametric form, one is one-cusp soliton for the CH equation while the other one is one-loop soliton for the DP equation. The approximate analytic solutions expressed by a series of exponential functions agree well with the exact solutions. It demonstrates the validity and great potential of homotopy analysis method for complicated nonlinear solitary wave problems.     

5-[{4-[2-(5,6,7,8-四氢-5,5,8,8-四甲基)萘氧-2-基]乙氧基}苄基]-2,4-噻唑烷二酮的合成

以2,5-二甲基-2,5-己二醇为原料,经氯化、傅一克反应、烷化、Knoevenagel缩合、还原反应制得5-【{4-[2-(5,6,7,8-四氢-5,5,8,8-四甲基)萘氧-2-基]乙氧基}苄基】-2,4．噻唑烷二酮,其结构经元素分析,IR和1H NMR证实。总收率6．3％。