在液-固色谱中溶剂强度与流动相中活性组分的关系

本文以液-固色谱中溶质计量置换保留模型为基础, 研究了二元体系溶剂强度与流动相中活性组分浓度之间的定量关系, 用80多组数据检验了这种关系的可靠性, 该模式的建立为液-固色谱中有效地选择洗脱体系及确定流动相中不同溶剂的比例, 提供了可靠的依据。     

芳香族羟肟的合成及其萃取铜的结构-性能研究

合成了一系列不同结构高纯度的芳香族羟肟, 测得了它们的反式羟肟含量和解离常数, 用HMO法计算了配位原子的电荷密度, 并用多元线性回归法研究了这类化合物的结构参数与其萃取铜反应平衡常数的关系。     

分光光度法同时测定两个干扰组份的研究 I.多波长数据线性回归法及其应用于同时测定微量锰和锌的探讨

In this paper, a linear regression method of multiwavelength data is proposed. The method, based on the difference of molar absorptivity between two coloured chelates at murti-wavelengths, can be applied to simultaneous spectrophotometric determination of two-interfering-component systems in the visible region. As an example, the availability as well as the optimum condition for simultaneous determination of Mn and Zn with 5-Br-PADAP in the presence of nonionic surfactant Triton X-100 have been studied. Measure the absorbance at 15 wavelengths over the range of 540-584 nm and treat the data with the suggested method, the linear correlation coefficients (γ) are found to be 0.998 in the synthetic mixtures containing microamounts of Mn and Zn with the concentration ratio from 1:10 to 10:1. The recoveries of both elements are 95-120% with the relative standard deviations (N=5) less than 17%. the method has been successfully used for direct determination of Mn and Zn in tap water. The new method proposed in this work is simple, fast and can be used for the analysis of two-interfering-component systems.     

含硫化合物的SK~αX射线荧光光谱的研究

在RIGAKU 3070X射线光谱仪(双晶)上系统测定了含硫化合物的SK~α谱; 用统计试验最优化方法处理实验数据, 得到了峰谱的峰位, 非对称因子, 半高宽度等信息; 并计算了化学位移和部分化合物硫原子的净电荷。讨论了硫化合物SK~α谱化学位移的变化规律及原因。线性回归分析结果表明: 硫化物SK~α谱的化学位移与价态, 硫的含氧化合物SK~α谱的化学位移与O/S原子数比之间都有较好的线性关系; 并给出了线性相关系数及线性方程。     

反相液相色谱操作参数最优化及水溶性维生素的分离

用最小二乘法拟合的多项式作为描述保留值或峰宽与流动相组成间关系的数学模型, 以影响水溶性维生素分离的主要因素(流动相中有机调节剂甲醇的浓度)作为主变量, 分析时间最短为目标, 各最难分离物质对的分离度≥1.5为约束条件, 在一定变量范围内对流动相组成进行了优化, 并运用此优化方法选择了维生素C、烟酸、烟酰胺、维生素B1、维生素B2和维生素B6六种水溶性维生素的最佳分离条件.     

电动势法对LiCl-Li~2SO~4-H~2O体系25℃热力学性质研究

用自制的锂离子选择电极和经典Ag-AgCl电极,测定25℃时LiCl-Li~2SO~4-H~2O三元体系中离子强度0.01～6.0mol.kg^-1的LiCl平均活度系数.,由实验数据,用多元线性回归法求取Pitzer方程、Harned方程的离子作用参数和系数,并用上述方程计算LiCl在混合溶液中的平均活度系数,分别以Inγ~±LiCl和logγ~±LiCl的形式与实验值进行比较,标准偏差均小于0.008.本工作测得的LiCl平均活度系数的自然对数与等压法测定的渗透系数拟合的Pitzer方程参数计算值比较,标准偏差为0.0097.同时计算了Li~2SO~4在该体系中的平均活度系数和混合溶液的渗透系数以及混合超额自由能.     

Nonexistence in power and gamma density regression, sum of nonnegative terms

When we use the power function α(c x)^b and gamma density αx^be^-cx to fit the data by the least squares method, we have to address the question of existence. The closure of the set of each type of these functions defined on a finite domain is determined. We derive a way to determine the closure of a sum of nonnegative functions if the closures of the summands are available.