目标识别因子分析解析完全未知混合体系的研究

本文以目标识别因子分析为基础, 将因子分析与聚类分析相结合, 给出了从完全未知混合体系中提取纯物种光谱的新方法。所得纯物种光谱经光谱检索作定性判别, 然后利用外标法对混合物中的各组份进行标定。该方法用于计算机模拟体系及三组份实际混合体系的红外光谱解析, 结果令人满意。     

完全未知混合体系的纯物种光谱辨析

基于因子分析的迭代目标转换算法,本文提出一种从完全未知混合物体系中获取纯物种光谱的解析方法。该法简单明了,不增加任何困难即可拓广至含n组份的混合体系,对光谱峰形状亦无任何附加限制要求。先采用计算机模拟技术对该法进行了校验,继用于紫外可见与荧光光谱的实际混合体系的解析,均获满意结果。     

不定物种的多组分体系同时测定：逐步回归法解析紫外光谱矢量数据的研究

本文采用逐步回归法对不定物种的多组分体系的紫外光谱矢量数据进行解析，可对物种及物种含量同时进行定性和定量分析，通过对两个复方药物体系（复方扑热息痛与复方维生素Ｂ）的紫外光谱数据的实际解析，表明本法能有效地完成混合物中物种及物种含量的同时定性和定量测定。     

完全未知混合体系中纯组份的红外光谱解析

提出一种新的目标转化因子分析，其初始向量的构造基于实际最大差异光谱，无需分离即可从红外混合体系中解析出纯组份光谱。该算法简单易懂，不必迭代，运算量小，应用于模拟及实际体系，结果令人满意。     

完全未知混合体系的纯物种光谱辨析

基于因子分析的迭代目标转换算法,本文提出一种从完全未知混合物体系中获取纯物种光谱的解析方法.该法简单明瞭,不增加任何困难即可拓广至含n组份的混合体系,对光谱峰形状亦无任何附加限制要求.先采用计算机模拟技术对该法进行了校验,继用于紫外可见与荧光光谱的实际混合体系的解析,均获满意结果.     

利用目标试验因子分析法确定化学反应的级数及速率常数

利用目标试验因子分析(TTFA)结合数值遗传算法(NGA).解析反应过程中在线测得的动力学谱-光谱数据矩阵,可在未知各组分纯光谱及动力学模型情况下同时求解出各组分的纯光谱、反应级数及速率常数。提出用近似计算法计算各组分的动力学谱,使该方法能适用于任意反应级数的体系。针对两步连续反应模型,对反应物、中间体和最终产物均有吸收及某一种组分没有吸收的体系的模拟实验数据矩阵进行了处理,表明该方法均能适用。利用该方法对邻苯二甲酸二甲酯在碱性介质中的水解反应及日落黄水溶液的电解降解反应过程中测得的数据矩阵进行解析,均获得了可靠结果。     

化学计量学方法解析苯胺电解过程

在对混合物样品的紫外可见光谱测量数据阵矩进行主成分分析、潜变量投影等方法解析后,得到一种物质的光谱曲线和另一种物质的动力学曲线,这在化学计量学意义上是一类比较特殊的黑色体系.提出了一种解析这个难题的算法,并详细论证了方法中不可避免的唯一解问题.对于模拟数据,解析结果证明本算法的正确性.用本法解析了苯胺水溶液电解过程,得到苯胺和中间物的动力学曲线及其纯光谱.     

直链烷烃近红外光谱的温度效应与应用研究

近红外光谱的温度效应已得到关注,在结构分析和定量分析方面得到了尝试.以直链烷烃为例,对烷烃有机体系近红外光谱的温度效应进行了研究.采集了20~60℃范围内五种直链烷烃(正己烷到正癸烷)及其混合物的近红外光谱并进行了对比分析,仅发现某些谱峰的强度随温度发生微小变化.采用交替三线性分解算法对光谱数据进行了解析,考察了光谱的特征以及随温度和结构的变化.结果表明,链端C₂H₅和链中CH₂基团的光谱受温度的影响不同,但其光谱信号的强度与温度之间都具有良好的线性关系,可根据光谱预测体系的温度;两种基团的光谱信号强度与烷烃分子的碳数或两种基团在分子中相对含量都具有良好的线性关系,可用于直链烷烃混合物组成的估算.     

利用目标试验因子分析法确定化学反应的级及速率常数

利用目标试验因子分析（TTFA）结合数值遗传算法（NGA），解析反应过程中在线测得的动力学谱－光谱数据矩阵，可在未知各组分纯光谱及动力学模型情况下同时求解出各组分的纯光谱，反应级数及速率常数，提出用近似计算法计算各组分的动力学谱，使该方法能适用于在任意反应级数的体系。针对两步连续反应模型，对反应物，中间体和最终产物均有吸收及某一种组分没有吸收的体系的矩阵进行了处理，表明该方法均能适用。利用该方法对邻苯二甲酸二甲酯在碱性介质中的水解反应及日落黄水溶液的电解降解反应过程中测得的数据矩阵进行解析，均获得了可靠结果。     

吸光度减技术在混合物分析中的应用

混合物的光谱是其组份光谱的叠加,直接对它进行解析是十分困难的,所以光谱工作者要在化学分离上耗费大量精力。富里埃变换红外光谱仪及其它计算机化的红外光谱仪器具有被称为吸光度减的功能,可用以进行光谱之间的带权相减。它在一定程度上代替了化学分离,把各组份的光谱从混合物光谱中一一“剥离”开来。此技术可广泛用于混合物分析和涉及混合物的研究工作。Koenig曾对此技术的应用作过     

A Study on the Competitive Permeability of Anions in Anion Exchange Membrane

The selective permeability of two species of critical ions coexisting in Solution 1 for a third species of ions of the same charge in Solution 2 penetrate through the anion exchange membrane has been studied. The competitive permeability of coexisting ions depends on various concentrations, compositions and reaction time with the restriction that the volume of solution in each compartment is finite. The species which is easy to exchange across the membrane in multi-ionic system has a high selective permeability at small composition and high total concentration condition. The experimental result shows that there exist overshooting and depletion effects for the fast ion when the reaction time is long enough, and the higher the permselectivity T^CL_OH is, the more appreciable the overshooting effect is. An explanation of the overshooting and depletion effects with finite volume of solution has been made specifically in discussion.     

Study of a composition of officinal herb mixtures using gas-liquid chromatography with mass-spectrometric detection

A composition of the volatile fraction of acetonitrile extracts of officinal herbs, used in the therapy of respiratory diseases, has been investigated. For each of the plant species we offered a set of markers, which made it possible to standardize a raw plant material and herb mixtures using a gas-liquid chromatography with mass-spectrometric detection.     

Simultaneous spectrophotometric determination of phenanthridine, phenanthridinone and phenanthridine N-oxide using multivariate calibration methods

The multivariate calibration methods, partial least squares (PLS) and principle component regression (PCR) have been used to determine phenanthridine, phenanthridinone and phenanthridine N-oxide in spiked human plasma samples. Resolution of binary and ternary mixtures of analytes with minimum sample pre-treatment and without analyte separation has been successfully achieved analyzing the UV spectral data. The net analyte signal (NAS) concept was also used to calculate multivariate analytical figures of merit such as limit of detection, selectivity and sensitivity. The simultaneous determination of three analytes was possible by PLS and PCR processing of sample absorbance in the 210–355 nm region. Good recoveries were obtained for both synthetic mixtures and spiked human plasma samples.     

Human liver dihydrodiol dehydrogenase 1-catalyzed reaction generating 9alpha,11beta-prostaglandin F2 from prostaglandin D2 followed by micellar electrokinetic chromatography

An enzyme reaction converting prostaglandin D2 (PGD2) into 9alpha,11beta-prostaglandin F2 (9alpha,11beta-PGF2) by a human liver-originated recombinant dihydrodiol dehydrogenase 1 (DD1) has been studied using CE. Four prostaglandins, viz. PGD2, 9alpha,11beta-PGF2, PGE2, and PGF2a (see Fig. 1, the latter two major PGs are possibly coexisting compounds in the assay mixtures), were completely separated by using SDS or PEG as buffer additives. Because analysis times in the SDS system were shorter than in the PEG system, SDS was employed in measurements of the enzyme activity of DD1. The pH dependence and the reaction temperature dependence of enzyme activity have been studied. The present method enabled us to detect all of the participants in the enzyme reaction: PGD2, 9alpha,11beta-PGF2, nicotinamide adenine dinucleotide phosphate (NADPH), and NADP+. Thus, direct, comprehensive, and reliable analysis of the enzyme reaction becomes possible. Enzyme activity has hitherto been estimated indirectly from the decrease of fluorescence derived from NADPH as an index of progress of the enzyme reactions in batch methods employed in conventional studies. In addition, the low sample consumption characteristic of CE should be a significant advantage of the present method in characterization of less commonly available enzymes such as the recombinant species used in this work.     

分光光度法同时测定无机多组分体系的研究III: 微量钨, 钼, 钛的测定

本文从配合物吸收光谱行为及矩阵运算角度分别探讨了CPA矩阵法AKC矩阵法中波长选择对分析结果误差的影响. 在前人有关钨, 钼, 钛单个元素光度测定研究的基础上, 确定了适宜于钨, 钼, 钛一苯基荧光酮-溴代十六烷基三甲铵三元配合物同时光度测定的最佳条件, 拟定了不经分离直接光度测定钨, 钼, 钛的方法.     

高灵敏度高选择性多组分痕量分析研究:卡尔曼滤波-分光光度法

本文根据卡尔曼滤波算法结合高灵敏显色反应提出了一种新的高灵敏度高选择性多组分痕量分析方法, 对卡尔曼滤波处理过程, 估计初值, 新息序列, 信息增量等作为分析结果评价, 波长数目选择的依据等基础性理论问题进行了探讨, 应用于十余种高灵敏显色反应体系, 对多种金属离子混合物及实际样品进行同时或分别测定, 可不经任何分离, 操作简便, 结果良好。     

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.     

Gel-permeation chromatography. V. A study of “overloading effects”

In the calculation of molecular weight averages from GPC chromatograms and in the correction for zone broadening effects, it is assumed that the retention volumes of the individual species are not affected by the presence of the other components in the sample (linear fractionation process). This assumption was tested by the computer comparisons of the chromatograms of mixtures of narrow molecular weight distribution polystyrene standards and the envelopes of the individual chromatograms of the components of the mixtures. Disagreements between experimental and computer synthesized chromatograms were interpreted as non-linear fractionation effects. The investigation covered a range of molecular weights (1.8 × 10⁶ to 2100), molecular weight distributions (binary and seven component mixtures), and sample loadings (2 to 70 mg). Accurate normalizations of raw GPC chromatograms and calculations of molecular weight averages were made possible through an automated GPC apparatus using a high-speed computer for data acquisition and data reduction. It was found that some nonlinear fractionation effects (large disagreement between chromatograms of the mixture and the computed envelopes of the individual chromatograms of the components of the mixture) became more pronounced as sample loading was increased and as the molecular weight distribution of the sample narrows. The nonlinear effect was also found to be sensitive to the molecular weight of the sample.     

Interaction between polyelectrolyte gels and surfactants of opposite charge

Investigations dealing with fundamental aspects of the interaction between covalently cross-linked polyelectrolyte gels and oppositely charged surfactants are reviewed. For reference, a brief summary of results from recent studies of associative phase separation in linear polyelectrolyte/surfactant mixtures is also included. It is found that great progress has been made in several sub-areas since the first reports appeared in the early 1990's. The frequently observed surfactant-induced volume transition has been studied in detail. Its relation to associative phase separation in solutions and the important role of polyion-mediated micelle–micelle attractions have been clarified. Phase separation in gels, in particular core/shell structures, has been studied in great detail. The importance of network mediated elastic forces between two phases coexisting in the same gel has been demonstrated and some of their consequences have been clarified. Hydrophobic interactions between polyion and micelle have been found to have strong effects on both binding and swelling isotherms. The effect of salt, which has been found to sometimes disfavor, sometimes promote surfactant binding, is quite well understood. The microstructure of gels in the collapsed state has been studied in great detail and is often found to be highly ordered, resembling liquid crystalline phases common to surfactant/water systems. The kinetics of surfactant binding and the associated volume change has been investigated to some extent. Progress has been made for gels displaying phase separation during the volume transition.