吸光光度法同时测定施尔康药物中痕量锌铁铜和锰

在pH8.5时,Zn(Ⅱ)、Fe(Ⅲ)、Cu(Ⅱ)和Mn(Ⅱ)均与2-(5-溴-2-吡啶偶氮)-5-二乙氨基苯酚和非离子表面活性剂聚乙二醇辛基苯基醚发生高灵敏的显色反应,生成稳定的三元胶束络合物,其λmax分别为558,556,560和567nm,表明吸收光谱严重重叠;在相应λmax处,其表观摩尔吸光系数分别为1.04×105,7.32×104,1.02×105和1.13×105L·mol-1·cm-1。用偏最小二乘法和迭代目标转换因子分析法等化学计量学法辅助吸光光度法,不经分离,同时测定了模拟样和施尔康药物试样中痕量锌、铁、铜和锰。虽然体系的加和性较差,但由于两种算法的优良性能,仍取得满意的结果。     

光度法同时测定地质样品中的钼钨锡锑

以水杨基荧光酮为显色剂,确定了光度分析法同时测定钼、钨锡、锑四组份的最佳条件。并采用迭代目标转换因子分析光度法,对地质样品中上述四组份进行了测定,测定结果的相对误差一般小于１０％。浓度矩阵的实验设计、主因子数的确定、干扰及消除等问题进行了讨论。     

A class of new iterative methods for general mixed variational inequalities

In this paper, we use the auxiliary principle technique to suggest a class of predictor-corrector methods for solving general mixed variational inequalities. The convergence of the proposed methods only requires the partially relaxed strongly monotonicity of the operator, which is weaker than co-coercivity. As special cases, we obtain a number of known and new results for solving various classes of variational inequalities and related problems.     

具有时滞的Volterra反应扩散差分方程的稳定性

本文考虑一类时滞Volterra反应扩散差分方程的初边值问题的正稳态解的稳定性。利用上下解方法和单调迭代方法得到了每一个解趋于方程的正稳态解的充分条件。     

A PRODUCT HYBRID GMRES ALGORITHM FOR NONSYMMETRIC LINEAR SYSTEMS

It has been observed that the residual polynomials resulted from successive restarting cycles of GMRES(m) may differ from one another meaningfully. In this paper, it is further shown that the polynomials can complement one another harmoniously in reducing the iterative residual. This characterization of GMRES(m) is exploited to formulate an efficient hybrid iterative scheme, which can be widely applied to existing hybrid algorithms for solving large nonsymmetric systems of linear equations. In particular, a variant of the hybrid GMRES algorithm of Nachtigal, Reichel and Trefethen (1992) is presented. It is described how the new algorithm may offer significant performance improvements over the original one.     

半参数回归模型的迭代法

在补偿最小二乘法则下,采用迭代法考虑半参数回归模型Li=Ai^TX＋s（ti）＋△i（i=1,2,……n,）得到参数及非参数的估计;接着从理论上证明了该法的可行性,并给出了误差上界及确定迭代的最大次数;最后用模拟的算例说明该法的有效性．     

改进的迭代目标转换因子分析研究

本文用非线性迭代偏最小二乘法分解原始数据阵,提出了改进的迭代目标转换因子分析法,大大简化了运算,方法简单、直观、准确.用此法对复方扑热息痛片中三组分(乙酰基水杨酸、扑热息痛及咖啡因)的含量进行紫外光谱测定,结果满意.     

H-单调映象的广义Fuzzy隐拟变分包含

引入了一类H-单调映象的广义Fuzzy隐拟变分包含问题,利用文[1]中H-单调映象的预解算子技巧研究了这类变分包含解的迭代算法逼近,证明了其解的存在性以及由算法生成的迭代序列的收敛性。     

Introducing memory to a family of multi-step multidimensional iterative methods with weight function

In this paper, we construct a derivative-free multi-step iterative scheme based on Steffensen’s method. To avoid excessively increasing the number of functional evaluations and, at the same time, to increase the order of convergence, we freeze the divided differences used from the second step and use a weight function on already evaluated operators. Therefore, we define a family of multi-step methods with convergence order $2m$, where $m$ is the number of steps, free of derivatives, with several parameters and with dynamic behaviour, in some cases, similar to Steffensen’s method. In addition, we study how to increase the convergence order of the defined family by introducing memory in two different ways: using the usual divided differences and the Kurchatov divided differences. We perform some numerical experiments to see the behaviour of the proposed family and suggest different weight functions to visualize with dynamical planes in some cases the dynamical behaviour.