轴向扩散型反应器恒温反应的近似解

根据轴向扩散模型求解的数学关键和化学反应的辩证本质,在轴向扩散模型一级不可逆反应解析解的基础上,由个别到一般,导出了动力学方程为幂函数型的各类均相反应浓度分布的近似积分方程。     

多孔催化剂非线性扩散—反应边值问题的近似解

基于大参数的假设提出了求解多孔催化剂内部非线性扩散－反应边值问题的近解的方法，在近似解的基础上，得到了计算有效因子的数学表达式。针对幂函数型这方程和Ｌａｎｇｍｕｉｒ－Ｈｉｎｓｈｅｗｌｗｏｏｄ型动力学方程，计算了三种不同形状催化剂颗粒的有效因子。     

单晶生长中的三相界面的近似解析解

本文考虑了单晶生长中的三相界面问题，即研究了气——液新月形界面满足的Ｌａｐｌａｃｅ－Ｙｏｕｎｇ方程２ｙ＝β〔ｙ″（１＋ｙ′２）３／２－ｙ′ｘ（１＋ｙ′２）１／２〕在边界条件为ｙ（∞）＝０，ｙ′（∞）＝ｂ＜０时的解，其中β＝２σ０／ｇΔρ是正常数（Ｌａｐｌａｃｅ常数）．我们得到了新月形高ｈ应满足的关系式：ｈ＝βｓｉｎ２α０２ｃｏｓα０以及新月形轮廓线的一个近似解析解ｘ＝１－（Ｉ－１βｙ２＋ｓｉｎα０２ｒｈｙ２）２ｓｉｎα０ｒｈｙ其中α０是三相边界（ｒ，ｈ）处的切角，Ｉ＝１１＋ｂ２．     

理想非线性双组分色谱方程解析解与GC实验结果的比较

在理想非线性单组分色谱分析的基础上，用ＧＣ做了理想非线性双组分色谱的流曲线。在非线性条件下，得出了各组分不同温度下的保留时间和最大浓度值。理想非线性双组分色谱的数学模型的解析解则通过双组分模型的理论公式结合计算机求解，解析解与实验结果进行了比较。     

陡坡坡面流的基本方程及其近似解析解

本文从物理原理出发,导出了描述降雨条件下的陡坡坡面流微分方程式,并通过量纲分析,比较了有林地和裸露地坡面的坡面流差异;对有充分前期降雨的恒定雨强条件(人工降雨),通过数学方法得出了描述汇流段和退水段的坡面流近似解析解     

混合条件下的连续源水污染模型的解析解

应用反应扩散方程的形式建立连续源水污染模型,结合初边值混合条件的情况,根据偏微分方程的常用解法并结合应用maple软件求出解析解.     

非线性单摆的精确解与近似解

本文指导非线性单摆的精确解及级数表达式。     

Hulthén势散射态的解析解

对改良的Manning-Rosen势的径向薛定谔方程任意l波散射态进行解析求解,得到按“K/2π标度”的相移公式和归一化的超几何函数表示的径向波函数。通过对散射振幅在极点解析性质的研究得到束缚态能级, 而特征值的数值结果与先前结果的比较进一步验证了本文结果的精确性。     

非线性边值问题的有限元近似解

利用配置－Galerkin方法研究了非线性两点边值问题的有限元解,通过引入Jacobi点建立了高精度的近似解,并给出了数值结果。     

反应罐直接还原过程动力学模型

在实验室反应罐直接还原过程动力学研究的基础上,建立了动力学模型——半焦收缩反应核模型,推导了动力学速度方程,以实验数据验证了动力学方程的适用性.     

Modified image analytical solutions for ground displacement using nonuniform convergence model

Based on the image theory,the analytical solutions of tunneling-induced ground displacement were derived in conjunction with the nonuniform convergence model.The reasonable value of Poisson ratio in the analytical solution was discussed.The ground settlement width parameter which could reflect the ground condition was introduced to modify the analytical solutions proposed above,and new analytical solutions were presented.To evaluate the validity of the present solutions using the nonuniform convergence mode...     

稳定态近似原理的数理根据

对于多相多组分且初始浓度不同的n级反应，除n＝1外，其速率方程的求解是十分复杂、繁琐的，多为难于求得精确解．因此，走近似求解之路已势在必行．其中稳态近似原理求解法是应用较多的．所提出稳态近似原理的数理根据，严格证明了它是一个科学的原理和方法．     

用改进的CSA法计算多元固溶体混合熵

CSA法在估算多元固溶体的混合料,骨比CVM法计算简单的优点,所以,CSA法特别适合于利用实验数据优化计算多元合金体系的相图,采用相同的能量参数及结构,比较了用蒙特卡罗（MC）法、CVM法及CSA法计算的结果,由此可知,由于CSA法引入了1个参数,增强了实用性,计算得到的Cu-Au相图与用蒙特卡罗（MC）法及CMV法计算的结果一致。     

Morphological evolution model for unidirectional solidification of multicomponent alloys

Based on the nonlinear interaction of the different species and the calculation of phase diagram, a self-consistent model is developed to describe the interface morphology evolution during unidirectional solidification of multicomponent alloys. This model takes full account of the mutually coupled effect of temperature field, solute field, interface energy and interface attachment kinetics. In comparison with linearization analysis of multicomponent, it not only extends the convergent range of the analysis, but also greatly improves the applicability.     

Mathematical model for coupled reactive flow and solute transport during heap bioleaching of copper sulfide

Based on the momentum and mass conservation equations, a comprehensive model of heap bioleaching process is developed to investigate the interaction between chemical reactions, solution flow, gas flow, and solute transport within the leaching system. The governing equations are solved numerically using the COMSOL Multiphysics software for the coupled reactive flow and solute transport at micro-scale, meso-scale and macro-scale levels. At or near the surface of ore particle, the acid concentration is relatively higher than that in the central area, while the concentration gradient decreases after 72 d of leaching. The flow simulation between ore particles by combining X-ray CT technology shows that the highest velocity in narrow pore reaches 0.375 m/s. The air velocity within the dump shows that the velocity near the top and side surface is relatively high, which leads to the high oxygen concentration in that area. The coupled heat transfer and liquid flow process shows that the solution can act as an effective remover from the heap, dropping the highest temperature from 60 to 38 °C. The reagent transfer coupled with solution flow is also analyzed. The results obtained allow us to obtain a better understanding of the fundamental physical phenomenon of the bioleaching process.     

翼型采用近似边界条件的欧拉方程数值解

1　IntroductionThe use of body- conforming curvilinear gridshas become the most common approach in modernComputational Fluid Dynamics ( CFD ) methodssince the early seventies.It is now almost thenorm of all CFD methods that use structured gridsfor complex geometries.However,the computertime and human work involved in generating thecurvilinear grids could be rather demanding,especially for problems involving motion of theflow boundaries such as in the aeroelasticsimulation of a deforming wi…     

Alkylated and silylated β-cyclodextrin for gas chromatographic chiral stationary phases

Three new ehiral stationary phases, 2, 6-di-O-heptyl-3-O-trimethylsilyl-β-cyclodextrin( DHTBCD), 2,6-di-O-pentyl-3-O-trimethylsilyl-β-cyclodextrin (DPTBCD) and 2,6-di-O-butyl-3-O-trimethylsilyl-β-cyclodextrin (DBTBCD), were synthesized. Chromatographie properties sueh as eolumn efficieney, thermal stability and eolumn life span, were studied. The separations of enantiomers, sueh as ketone, esters, alcohols and olefines, were investigated on the alkylated and silylated β-eyelodextrin stationary phases. The influenee of diluent on ehiral separation was studied. The experimental results indieate that the stationary phases show good ehromatographie properties in separating enantiomers. It is observed that inelusion eomplexafion and hydrogen bonding interaction hardly play a role in separating enantiomers.     

基于小波变换的重叠色谱峰检测方法研究

为了构建一种色谱数据处理方法,可以同时解决包含肩峰的复杂重叠色谱峰群检测中的噪声滤除、基线校正和谱峰辨识等问题,作者利用小波变换多分辨分析及奇异性检测原理,提出了一种色谱信号处理的新方法.通过对仿真和实验数据处理的结果表明:该方法检测重叠色谱信号无须专门的滤波和基线校正步骤,可以确定出色谱图中包含肩峰在内的复杂峰群各特征点位置和峰形情况.用该方法开发的检测算法只需设置两个参数,方便了计算机的自动处理.     

FRP约束混凝土圆柱应力-应变分析模型

为精确模拟FRP约束混凝土的单轴受压性能,提出了FRP约束混凝土圆柱应力-应变分析模型的建立方法.在分析国内外大量试验数据基础上,依据八面体强度准则提出了FRP约束混凝土圆柱极限强度的计算方法,分析FRP约束混凝土圆柱极限应变与侧向约束强度的关系,建立了极限应变的计算方法;分析应力-应变全曲线试验结果中轴向应变与环向应变的关系,建立由轴向应变确定环向应变的计算公式;以Mander本构模型为主动约束关系,采用增量方法计算了FRP约束混凝土圆柱的应力-应变系曲线,模型预测结果与多数试验结果吻合较好.