用Microsoft Excel对实验数据处理的方法

介绍采用Microsoft Excel2000对实验数据进行处理和数据分析。该种方法既可简化大量平行数据取平均值的计算，又可根据数据进行自动绘图，而且在图表生成后只要修改某个数据图形会自动调整。该文同时详细介绍用此方法对邻二氮菲分光光度法测定微量铁绘制吸收曲线和标准曲线的方法。     

4-氨基安替比林分光光度法测定水中微量苯胺类化合物的研究

使用4-氦基安替比林分光光度法测定水中微量苯胺类化合物,实验操作简单,具有很好的灵敏度。该方法的检出限、精密度和准确度均能满足水和废水中微量苯胺类化含物分析的要求。     

回归曲线在分析测试中的应用

一、前言 炼油厂入口微量油分析是常规分析化验项目,其数据来源于回归曲线中的K值和光密度的乘积。在分析试样时,要求先用标准物绘制标准曲线,国家环保局统编的分析方法中也要求绘制标准曲线,以往使用的分光光度计虽然本身也能处理实验数据绘制标准曲线,但是在获得多组实验数据,运用标准曲线求被测物的含量,方法本身带有很大误     

有机化学比较实验项目化的探索与实践

根据有机化学实验教学的现状和特点,结合多年来的实验教学经验,设计了一个有机化学比较实验项目:甲基橙的合成。本项目通过对原有的多种合成方法的进行验证比较,提出微量法合成甲基橙。该法经学生微量化实验实践效果令人满意,项目训练有效的提高学生的创新与综合实验能力。     

测定水中总氮工作曲线的改进方法

按国标GB1194-89检测水质总氮的方法,对工作曲线进行了改进,不经消解而直接显色测定。通过对比试验、标准样品考核、实际水样测定、加标回收率测定,表明改进后的方法与国标法无显著差异性。该措施可以提高总氮测定的工作效率,简化实验步骤,满足检测要求。     

火焰原子吸收光谱法测定大豆豆渣中微量金属含量的研究

在最佳实验条件下,采用火焰原子吸收光谱法测定大豆豆渣中微量金属铜和锌的含量。实验结果表明,该方法标准曲线的线性关系好,加标回收率为92.0%～100.4%,相对标准偏差小于5%,说明该方法简便快速,准确度和精密度高。     

微量尿素分析过程优化

水中微量尿素的分析方法为二乙酰基一肟比色法,此法标准曲线制作难度较高,一般相关系数仅为0.99,甚至0.9,一般实验室要求标准曲线相关系数至少达到0.999,通过大量实验,从实验用水、试剂,以及操作过程中找出了影响分析方法的因素,最终实现目标。     

磷酸氢二钠中微量氯根的分光光度法测定

氯根的测定,通常是用硝酸银直接滴定1。对于微量氯根的测定又有电位滴定法2及汞量法3。这些方法在测定磷酸氢二钠中微量氯根时,存在着干扰大、费时、滴定误差大等缺点,影响了分析结果的准确性。由于氯化银的稳定性不易掌握,利用分光光度法测定微量氯根的方法未见报道。本文研究了以HNO3为介质在聚乙烯醇作稳定剂的条件下,用分光光度法测定磷酸氢二钠中的微量氯根。实验结果表明,该方法操作简便,稳定性及重现性好,结果可靠,由此建立了测定微量氯根的新方法。1、实验部分1.1　仪器与试剂分光光度计:7230型,上海分析仪器厂。Cl-标准溶液(1.0m…     

原子吸收分光光度法测定野蜂蜜中微量金属元素含量

采用原子吸收分光光度法测定了野蜂蜜中Fe、Cu、Ca、Mg、Mn、Zn等微量金属元素的含量,建立了Fe、Cu、Ca、Mg、Mn、Zn的标准工作曲线方程及其线性范围.该法简便易行,可连续测定多种微量金属元素的含量,效果较好.     

地方院校开展微型有机化学实验教学初探

选取几个典型的基础有机化学实验,通过常量、半微量、微量的比较实验,揭示了微型实验教学的一些优点和存在的问题,并提出了解决的方法。确认微型实验是实验改革的方向。     

一种简便的评价TiO2晶核剂效果的方法

使用差热分析方法测定玻璃的转变温度Ｔｇ和液化温度Ｔｍ。假定与形核方程和生长方程相联系的几个参数是固定不变的,作样品的形核和生长速率曲线,发现样品中ＴｉＯ２的含量越高,在形核和生长速率曲线间的距离越大,同时相应的最大形核的生长速率的相对温度越低。     

低收缩添加剂对聚酯树脂固化的影响

本文采用SPI法测定加入不同含量低收缩添加剂（LPA）的不饱和聚酯树脂的固化放热曲线。研究了低收缩添加剂的用量，以及中低温固化体系对不饱和聚酯树脂的凝胶时间，固化时间，放热峰温度，固化放热量的影响。     

流化床干燥器中临界湿含量测定

介绍用气相法和固相法测定流化状态下物料临界湿含量的方法，并将实验结果与洞道式干燥器中测得的数据做了比较。结果表明，用气相法测定流化状态下物料临界湿含量具有操作简便、快速和省料的优点。     

顶空气相色谱法测试瓶片乙醛含量标准曲线的制作研究

论述了瓶级聚酯切片顶空气相色谱法测试乙醛含量的标准曲线制作方法,对色谱进样量、线性范围等操作细节进行了研究,使得方法的重复性和再现性得到改善,可操作性强,确保瓶片及其制品的乙醛含量测试准确。     

离子选择电极法测定净化湿法磷酸中氟含量的方法比较

分别采用标准曲线法和标准加入法测定净化湿法磷酸中氟含量,考察两种方法测定结果的差异。实验结果表明,标准曲线法的相关系数(R2)均在0.999 5以上;当加入氟标准溶液体积不小于0.5 m L,标准加入法可替代标准曲线法对湿法精制磷酸中氟含量进行测定。该方法简便、快速、可靠,可推广至生产应用中。     

FP—640火焰光度计测定氯化铵中氯化钠的含量

介绍了FP—640火焰光度计采用低、高标法钠含量的测定。与标准曲线法钠含量测定相比较,该法具有方便、快速、准确度高的特点。     

缩合废水COD测定中氯离子的影响及消除

根据缩合废水中氯离子含量高,对COD测定影响较大的特点,通过实验探讨高含氯对测定废水COD的影响及消除其影响的方法。以重铬酸钾法测定COD,消除氯离子的干扰,一般是采用添加HgSO4的方法。该方法操作简便,但汞盐易对环境造成二次污染。文章采用标准曲线校正法不加HgSO4,能较准确地测定高氯缩合废水中的COD。     

A Method for Determination of Absorption Isotherms at High Relative Humidity Levels: Measurements on Lime-Silica Brick and Norway Spruce (Picea abies (L.) Karst.)

The relationship between the relative humidity and the moisture content of a material (for relative humidity levels close to 100%) can be studied using the pressure plate technique. However, this method is designed for desorption experiments and modifications are necessary in order to perform absorption experiments. This article presents a method to condition samples to a uniform moisture content by absorption with the pressure plate technique. The specimens were suspended in magnetic clamps until the ceramic plate had equilibrated with the applied pressure and modifications were made so that water could circulate through the pressure plate cell.     

MEASUREMENT ERRORS PROCESSING BY COVARIANCE ANALYSIS FOR AN IMPROVED ESTIMATION OF DRYING CHARACTERISTIC CURVE PARAMETERS

ABSTRACT

The aim of this paper is to show the interest of the covariance analysis applied to measurement error in the particular case of the identification of a drying characteristic curve from experimental drying data. The modelisation of drying by use of the Drying Characteristic Curve (DCC) method is first presented with usual specifications (power function, critical moisture content …). The experimental procedure used to obtain drying curves and the data processing are detailled and analysed. Measurements errors are identified at the first step of the procedure and their effects on the estimation error of the exponent α of the power function are estimated. Three different methods for estimating α are presented under their matrix form: the least square method and two methods based on the «Gauss–Markov» or «Maximum likelihood» theorem, firstly under a simplified form suited if the estimation errors are uncorrelated and secondly under a complete form suited even if the estimation errors are correlated. These three methods are applied to experimental results obtained with ginger roots drying. The value of the exponent α of the power function and then the distances between the three corresponding theoretical drying curves (representing product water content vs. time) and the experimental points are studied. It is shown that in this particular application, the complete Gauss–Markov method leads to the better fitting and that the simplified Gauss–Markov method, since it is a priori non appliable in this case where errors are correlated, gives quite better results than the oridnary least squares method. The covariance matrices of the estimation errors of reduced water content, reduced drying rate and exponent α are also presented in order to show the correlations existing between the measurement errors of each variable during a drying cycle.     

A SHORT-CUT METHOD FOR DETERMINING CONCENTRATION DEPENDENT DIFFUSIVITY IN LIQUID FOODS AND POLYMER SOLUTIONS FROM REGULAR REGIME DRYING CURVES

A simple method for determining concentration (water or solvent content) dependent diffusivity in liquid foods and polymer solutions from the regular regime drying curve was developed on the basis of the power-law diffusion model. The method was first tested to the drying data generated from numerical solutions of the diffusion equation with various types of concentration dependent diffusivities. The present method was found to be very simple yet accurate compared with the previous methods. Then, the drying rates of various sugar solutions experimentally obtained were analyzed on the basis of the present method to determine the moisture content dependent diffusivities.