二氧化碳基聚碳酸酯二元醇末端羟基含量的测定

羟值滴定是一种基于羟基的化学特性，通过定量二元醇中的末端羟值从而表征二元醇分子量的化学分析方法。聚氨酯通常是以多元醇和多异氰酸酯为原料通过羟基(—OH)和异氰酸酯基团(—NCO)之间的聚加成反应得到，且—OH与—NCO的比例尤为重要，因此需要准确计算所用二元醇中羟基含量。以环氧类化合物和CO₂为原料直接合成的聚碳酸酯型二元醇(PCDL)粘度大且与水互溶性差，因此本文用改进的乙酸酐-甲基咪唑-二甲基甲酰胺滴定方法对市售和自制PCDL进行羟值滴定测试，详细探讨了滴定过程中的各种因素对滴定结果的影响。优化后的羟值滴定方法相比于行业标准方法，减少了样品和试剂用量且酰化反应仅需在45℃水浴20 min完成，节约了测试时间，提高了羟值滴定效率。     

微分倒数示波计时电位法的研究—定量测试及滴定分析

首次利用微分倒数示波图定量测试微量金属离子并滴定分析药物，结果满意。     

小波变换用于电位滴定法测定极弱酸

研究了用小波变换确定电位滴定终点方法测定硼酸和苯酚两种极弱酸,同经典方法及其它数学方法的结果进行比较,说明用小波变换电位滴定法测定极弱酸快速,准确,可为极弱酸的计算机联机测定提供一种新的途径。     

一种自动微量滴定新方法

本文依据传统滴定分析原理，利用流动注射装置提出一种新的自动微量滴定方法，它不仅具有流动注射滴定分析法简便快速，试剂和试样消耗少，仪器装置简单等优点，而且测定信号怀被测组分的浓度直接成线性关系，结果的准确度和精度优于一般流动注射滴定方法。通过用盐酸滴定氢氧化钠进行验证，相关系数为０．９９９９，相对标准偏差（ＲＳＤ）为０．４％。     

非水滴定法测定酰胺缩醛

对非水滴定酰胺缩醛的溶剂、滴定剂和指示剂进行了选择试验，用ＨＣｌ甲醇标准液进行滴定，通过电位滴定曲线或甲基橙指示剂可以准确的确定滴定终点，方法简便，结果准确。     

重铬酸钾滴定法测定低品位多金属矿石中全铁含量

三氯化钛还原重铬酸钾滴定法测定低品位多金属矿石中全铁含量是一种常见的检测方法,其根据指示剂的颜色变化指示滴定终点,然后目测标准滴定溶液消耗的体积,计算分析结果。通过试样的测试,对分析结果精密度和准确度进行了考察,相对标准偏差RSD均小于1.000%,加标回收率为94.6～100.0%,可用于低品位多金属矿石中全铁含量在0.500%及以上的测定。     

直接测定法测定葡萄酒中糖含量操作条件的探讨

通过分析滴定温度、滴定碱度、热源温度、沸腾时间和滴定速度等操作条件，探讨了操作条件对直接滴定法测定葡萄酒中糖含量的影响，确定了最佳操作条件，提高了测定结果的准确度。     

镉离子选择电极电位滴定测定钙镁

建立了以镉离子选择电极极作指示电极ＥＤＴＡ、ＥＧＴＡ电位滴定测定钙、镁的方法，详细考察了电位滴定的适宜条件，干扰离子的影响及消除办法。在四硼酸钠－氢氧化钠缓冲介质中，ＥＧＴＡ滴定钙，ＥＤＴＡ滴定钙镁含量，测定矿泉水及硅酸盐样品中钙镁含量，结果符合要求。     

微型滴定在定量化学分析中的应用

本文在讨论微型滴定装置和滴定误差的基础上，探索了微型滴定在酸碱、络合、氧化还原和沉淀滴定中应用的可能性。结果表明，效果良好     

通过Boltzmann拟合方程定量计算Al(Ⅲ)盐强制水解聚合溶液中的羟基多核铝型体

在表征聚合铝的3种传统测试方法中,只有酸碱电位滴定法至今还没有用于定量计算羟基多核铝。本文依据Al(Ⅲ)盐强制水解聚合过程的电位滴定实验结果,利用铝盐水解聚合电位滴定曲线的三个临界特征点,同时利用Origin软件自备的Boltzmann方程对滴定曲线拟合,可以很方便地计算出铝盐强制水解聚合溶液中聚合铝的含量。模式计算结果与Al-Ferron逐时络合比色法的测试结果线性符合较好,为研究Al(Ⅲ)盐水解聚合过程及其聚合铝形态的定量测定尝试了一种新的方法。     

利用滴定曲线方程和Origin精确绘制滴定曲线*

滴定曲线是滴定分析原理的重要内容。它显示了滴定过程中平衡体系性质的变化,可以获知化学计量点和滴定突跃信息,从而指导准确滴定判别或指示剂的选择。滴定曲线方程是滴定过程中体系的某种性质X(例pH)与滴定分数a(或滴定剂体积V)的关系方程,解析方程可获得函数X=f(a)的表达式。对一些较复杂的体系,推导函数X=f(a)较困难,但多数情况下反函数a=g(X)的推导更容易,表达式也更简洁。本文对酸碱、配位、氧化还原和沉淀滴定曲线方程进行了系统总结,并对不同情况下的函数X=f(a)或反函数a=g(X)进行了推导,拓展了教材内容。根据函数关系,在Origin中利用其函数绘图功能可直接绘制出滴定曲线,不用先生成数据点再绘图,方便快捷。用反函数绘图时增加数据点即可获得高精度的滴定曲线,可直接从滴定曲线上查找化学计量点和滴定突跃信息。     

The use of glass electrodes for the determination of formation constants--I: A definitive method for calibration

The computer program, MAGEC (Multiple Analysis of titration data for Glass Electrode Calibration), described can optimize simultaneously any or all of the titration parameters pertinent to the calibration of glass electrodes. In particular, the protonation constants of a ligand and the glass-electrode parameters may be determined simultaneously from a given single set of titration data. A method is described for obtaining definitive values of these parameters, involving cyclical treatment of titration data by means of MAGEC and another program such as MINIQUAD. The use of MAGEC for evaluating the performance of a glass electrode or as an analytical tool for determining, with high precision, the concentrations of acid and base solutions, is also described.     

Multiparametric curve fitting-VII Determination of the number of complex species by factor analysis of potentiometric data

The number of complex species in solution may be determined by a computer-assisted factor analysis of a set of potentiometric titration curves, by finding the rank of the normalized data matrix. An application of the program SPECIES is demonstrated for some examples of titration data. The method is limited in that it can discriminate only between species with differing degrees of polymerization.     

The titration error in potentiometric precipitation titration

The titration error can be calculated with the aid of the value of the buffer index determined at the inflection point of the titration curve when a precipitation titration is followed with an ion-selective electrode. When the precipitate is not formed ideally in the titration (i.e., is not formed under equilibrium conditions) the titration error cannot be predicted from the values of the solubility product, nor can the values of the solubility product be calculated from titration data at the inflection point.     

Determination of the composition and the stability constants of complexes of mercury (II) with amino acids

The execution of a titration rarely performed, or of one with a reagent of limited stability, may be facilitated by applying multiparametric curve-fitting to titration-curve data in such a way that the amount of the substance titrated and the concentration of the reagent are evaluated simultaneously; the necessity for prior standardization of the reagent is thereby eliminated. In the potentiometric titration of acetate ion, a very weak base, with unstandardized hydrochloric acid, the accuracy and precision of the concentration of acetate thus obtained are approximately five times better than those which can be secured by titration with standardized acid and location of the point of maximum slope. The accuracy and precision of the concentration of acid are comparable to those that can be secured in very careful standardizations against a primary standard that gives a titration curve of far more favorable shape.     

Fitting and Analyzing pH Titration Curves on a Graphing Calculator

The pH titration curve is a well-known figure in chemistry. It is easy to plot this graph from experimental data by measuring pH as a function volume of added titrant; however, there is no simple mathematical equation of expressing pH as a function of titrant volume. The logistic function has been suggested but, as discussed in this paper, it is inadequate for modeling titration curves. Developed in this paper is a piecewise continuous function (with chemically meaningful parameters) of pH versus volume. A program has been written to display this function on a graphing calculator. This program can be used by students (1) to analyze the characteristics of pH titration curves, for example, the derivative and the presence of two inflection points, and (2) to interactively fit experimental titration data that they have collected.     

Simultaneous determination of equivalence volumes and acid dissociation constants from potentiometric titration data

New iterative methods for analysis of potentiometric titration data of (a) mixtures of weak monoprotic acids with their conjugate bases, (b) solutions of polyprotic (di- and triprotic) acids, and (c) mixtures of two diprotic acids are presented. These methods, using data exclusively resulting from the acidic region of the titration curve permits the accurate determination of the analytical concentration of one or more acids even if the titration is stopped well before the end point of the titration. For the titration of a solution containing a conjugate acid/base pair, the proposed procedure enables the extraction of the initial composition of the mixture, as well as the dissociation constant of the concerned acid. Thus, it is possible by this type of analysis to distinguish whether a weak acid has been contaminated by a strong base and define the extent of the contamination. On the other hand, for the titration of polyprotic acids, the proposed approach enables the extraction of the accurate values of the equivalence volume and the dissociation constants K(i) even when the ionization stages overlap. Finally, for the titration of a mixture of two diprotic acids the proposed procedure enables the determination of the composition of the mixture even if the sum of the concentrations of the acids is not known. This method can be used in the analysis of solutions containing two diastereoisomeric forms of a weak diprotic acid. The test of the proposed procedures by means of ideal and Monte Carlo simulated data revealed that these methods are fairly applicable even when the titration data are considerably obscured by 'noise' or contain an important systematic error. The proposed procedures were also successfully applied to experimental titration data.     

Modeling the acid-base surface chemistry of montmorillonite

Proton uptake on montmorillonite edge surfaces can control pore water pH, solute adsorption, dissolution kinetics and clay colloid behavior in engineered clay barriers and natural weathering environments. Knowledge of proton uptake reactions, however, is currently limited by strong discrepancies between reported montmorillonite titration data sets and by conflicting estimates of edge structure, reactivity and electrostatics. In the present study, we show that the apparent discrepancy between titration data sets results in large part from the widespread use of an erroneous assumption of zero specific net proton surface charge at the onset of titration. Using a novel simulation scheme involving a surface chemistry model to simulate both pretreatment and titration, we find that montmorillonite edge surface chemistry models that account for the "spillover" of electrostatic potential from basal onto edge surfaces and for the stabilization of deprotonated Al-Si bridging sites through bond-length relaxation at the edge surface can reproduce key features of the best available experimental titration data (the influence of pretreatment conditions on experimental results, the absence of a point of zero salt effect, buffer capacity in the acidic pH range). However, no combination of current models of edge surface structure, reactivity and electrostatics can quantitatively predict, without fitted parameters, the experimental titration data over the entire range of pH (4.5 to 9) and ionic strength (0.001 to 0.5 mol dm(-3)) covered by available data.     

非终点滴定法与其应用

为了实现滴定分析的快速和自动化,本文借鉴以往研究的经验针对其不足[1~8],提出了一种新的分析方法,滴定中只要加二次标准液,将采集到的数据通过适当的数学计算,即可得到样品液的浓度,本法不需要已知反应常数、电极转换系数等,对中和度没有严格要求[9~11],故具有可操作性和实用性。本法不需要确定终点,不需要全过程滴定,为滴定分析的自动、快速化提供了充分的条件,特别适合冶金、环境、食品、药品的大批量快速分析和在线分析。根据该方法的原理即可开发出一种新的自动分析仪。     

Miniglass,an interactive program for the evaluation of stability constants of metal/ligand complexes from potentiometric data

MINIGLASS is a microcomputer program for the treatment of pH titrations for evaluation of stability constants and adjustment of the parameters defining the titration curve. The program is written in PASCAL for the HP-200 computer series, and contains procedures for blank titrations, acidity constants and metal/ligand stability constants. Graphics support is provided for easy interaction with the user. The data files can be written by the editor of the operating system or can be created automatically from an automatic titration system. The program is tested for the determination of the formation constants of the well-studied Ni²⁺/glycine system. The results obtained agree well with literature values.