The problem of diffusion and reaction in catalyst pellets is considered for the case of nth order reactions. The Adomian decomposition method is used to solve the nonlinear model of diffusion and reaction and to obtain approximate solutions. The variation of reactant concentration in the catalyst pellet and the effectiveness factors are determined for second-, half-and first order reaction. The approximate analytical solutions obtained are compared with solutions obtained with a finite difference numerical method. In general, the Adomian polynomial method with three terms gives solutions comparable to the numerical procedure for Thiele modulus approximately up to 4.0.

The problem of the process of coupled diffusion and reaction in catalyst pellets is considered for the case of second and half order reactions. The Adomian decomposition method is used to solve the non-linear model. For the second, half and first order reac tions, analytical approximate solutions are obtained. The variation of reactant concentration in the catalyst pellet and the effectiveness fac tors at φ<10 are determined and compared with those by the BAND's finite difference numerical method developed by Newman. At low er values of φ, the decomposition solution with 3 terms gives satisfactory agreement with the numerical solution; at higher values of φ, as the term nmnber in the decomposition method is increased, an acceptable agreement between the two methods is achieved. In general the solution with 6 terms gives a satisfactory agreement.

用低温合成法制备出不同Pt掺杂量的Pt-W-Ru-Se催化剂，应用旋转圆盘电极电位扫描法测试其对氧还原反应的催化作用，采用XRD、EDS、XPS技术表征结构及表面组成。结果表明，Pt能够显著增强W-Ru-Se对氧还原反应的催化活性，尤其以含5%Pt（质量分数，下同）的Pt-W-Ru-Se催化剂最为明显，在0.5mol•L-1H2SO4中其对氧还原反应的电催化活性超过了W-Ru-Se和Pt；甲醇存在时，其稳定性和抗甲醇性也都超过了Pt。

应用两步化学还原法合成不同壳层厚度的Fecure-Ptshell纳米粒子，并用SEM、TEM、EDS和XRD手段对其进行物理表征，应用动电位、交流阻抗和循环伏安法进行氧还原电催化活性及抗甲醇性测试。结果表明，样品Fecore-Ptshell纳米颗粒粒径分布集中，其中Fecore-Ptshell0.5平均值为50nm，核芯直径约34nm，壳层厚度约8nm；与Pt/C相比，Fecore-Ptshell/C对氧还原的催化活性和抗甲醇性明显提高，Fe与Pt原子比为1：0.5的Fecore-Ptshell//C在0.5mol•L-1H2SO4中氧还原的最大峰电流密度可达到184.7mA•mg-1，是相同反应条件下Pt/C电流密度的1.45倍。抗甲醇性显著提高。

通过对纯铝板电化学阳极氧化及腐蚀液处理，在～定的条件下制备出了排布有序的Al2O3纳米线，采用SEM、EDS、IR手段对纳米线微观形貌和组成进行了表征。实验结果表明：多孔Al2O3薄膜经腐蚀后形成纳米线，在铝基板上呈六角形排布，组成为纯A1203，直径随电氧化温度、槽电压的升高和腐蚀处理时间的延长减小，直径范围为16～60nm，长径比较大。在实验的基础上，提出了有序排布Al2O3纳米线的形成机理。