新制氢氧化钙溶度积测定方法研究

通过正交试验分析得到配位滴定法测定Ca     

阴离子表面活性剂的测定方法——混合指示剂程序加入法

在原有的混合指示剂 (MIT)法的基础上 ,提出一种改进的测定阴离子表面活性剂的两相混合指示剂程序加入 (MIST)法 ,并分别在纯体系和复杂体系中对两种方法进行了比较 .结果表明由于 MIST法减少了滴定过程中的化学反应和化合物在两相之间的相转移 ,因而减小了相应的影响因素 .在稀阴离子表面活性剂溶液的分析中其标准偏差 s不大于 0 .4 % .     

控制电位滴定法的误差分析

研究了影响控制电位滴定法测定结果准确度的因素,得到的结论是:第一,电位的控制误差及滴定剂体积的测定误差是影响控制电位滴定法测定结果准确度的主要因素.计算模型中的比例系数越大,滴定曲线的变化率越大,这种影响越小.第二,多组分体系的测定误差,与组分在计算模型中比例系数的相对大小有关.比例系数越大,测定误差越小.第三,不同浓度(或不同浓度比)待测溶液滴定曲线的差异越大,对控制电位滴定法的测定越有利.     

End-point detection in potentiometric titration by continuous wavelet transform

The aim of this work was construction of the new wavelet function and verification that a continuous wavelet transform with a specially defined dedicated mother wavelet is a useful tool for precise detection of end-point in a potentiometric titration. The proposed algorithm does not require any initial information about the nature or the type of analyte and/or the shape of the titration curve. The signal imperfection, as well as random noise or spikes has no influence on the operation of the procedure.The optimization of the new algorithm was done using simulated curves and next experimental data were considered. In the case of well-shaped and noise-free titration data, the proposed method gives the same accuracy and precision as commonly used algorithms. But, in the case of noisy or badly shaped curves, the presented approach works good (relative error mainly below 2% and coefficients of variability below 5%) while traditional procedures fail. Therefore, the proposed algorithm may be useful in interpretation of the experimental data and also in automation of the typical titration analysis, specially in the case when random noise interfere with analytical signal.     

固定pH滴定法测定Vc片中抗坏血酸

本文采用固定ｐＨ滴定法测定Ｖｃ片中抗坏血酸的含量，其结果与药典法测定值一致，ＲＳＤ≤１．９％，回收率在９８．６％￣１１．６％之间，实验结果表明，该方法操作简便，分析快速，结果准确。     

微型滴定法测定饮品中的总酸度

本文利用微型滴定法测定饮品中的总酸度，并对微型滴定法与常量滴定法的平行测定结果进行了比较，结果无显著性差异，F检T检结果均在允许范围内，相对偏差均小于0．5％，微型滴定法的精度达到常量滴定法测定水平，能满足化学分析要求．     

Potentiometric and volumetric determination of 6-mercaptopurine

Three methods for the determination of 6-mercaptopurine in the pure state and in tablets are described. One method is based on the reaction of this compound with silver ions, whereby an equivalent amount of nitric acid is liberated, the latter being determined potentiometrically with sodium hydroxide. The other two methods involve titration with chloramine-T, with potentiometric and visual end-point-detection. All methods afford accurate and reproducible results and can be used for routine assay of 6-mercaptopurine in tablets.     

Application of isotachophoretic and conductometric methods for neomycin trisulphate determination

Determination of neomycin trisulphate (NMS) in a dosage form (Neox and Neosol) was carried out by capillary isotachophoresis (cITP) with conductometric detection. The following electrolytes: leading: 10 mmol dm⁻³ sodium acetate + 0.08 % hydroxyethylcelulose (HEC) and acetic acid to pH = 5.5, and terminating: 10 mmol dm⁻³ β-alanine were tested for isotachophoretic separation of NMS. The calibration curve was linear over the range of 10.00 mg dm⁻³ to 100.00 mg dm⁻³ with LOD = 5.69 mg dm⁻³ and LOQ = 18.96 mg dm⁻³. The results were compared to the conductometric determination of NMS with: ammonium molybdate (VI), silver nitrate (V) and Reinecke salt. Good accuracy was obtained from conductometric titration of NMS with Reinecke salt, the recoveries being as follows: 100 % (RSD = 1.99 %); 96.17 % (RSD = 2.10 %) and 95.22 % (RSD = 1.55 %) for NMS in pure form, Neosol and Neox, respectively.     

铝合金中六元素的炉前化学分析法

对现有的铝合金化学分析方法进行了筛选、简化，并作了适当改进，建立了铝合金中硅、铜、锰、铁、镁和锌六元素的快速分析方法，该法的特点是设备投资少、分析速度快、准确度较高，适用于炉前分析，对化验设备较简陋的乡镇企业尤其适用．     

Water-soluble γ-cyclodextrin polymers with high molecular weight and their complex forming properties

Polymeric cyclodextrins (CDs) derivatives combine the complex forming properties of CDs and properties of polymers such as high molecular weight and high solubility, justifying the increasing interest for its use in biomedical science. In this paper, a series of water-soluble epichlorohydrin/γ-CD polymers were synthesized and the influences of the epichlorohydrin/γ-CD ratio, NaOH concentration and reaction time were studied in order to get high molecular weight polymers. The M_w distribution and CD content of the polymers were determined by size exclusion chromatography and ¹H NMR, respectively. The complexing properties of the polymers were studied by isothermal titration calorimetry using Methyl Orange (MO) and Sodium Fusidate (Fus) as guests for the γ-cyclodextrin host. The complex formation with MO is exclusively enthalpy driven whereas the one with Fus is totally entropy driven.