裉色光度法测定SO^2—3的研究

本文研究了ＳＯ＾２－３褪色碱蓝６Ｂ的反应，在ｐＨ５．２Ａｃ－ＮａＡｃ缓冲介质中，ＳＯ＾２－３浓度在０．３９－１２ｍｇ／Ｌ范围内符合比尔定律，仅Ｆｅ＾３＋，Ｎｉ＾２＋，Ｃｒ＾３＋干扰测定，用于食品中ＳＯ＾２－３的测定，结果令人满意。     

偶合反应化学发光法测定痕量银的研究——K4Fe（CN）6—Luminol体系

将Ａｇ（Ｉ）催化Ｋ４Ｆｅ（ＣＮ）６的水合反应与Ｌｕｍｉｎｏｌ同Ｃｕ（ＣＮ）＾２－４的化学发光反应相偶合，建立起一种新的灵敏测定痕量银的化学发光分析法，在所研究的优化条件下，该法测定银的选择性较好，检测限达到４．０×１０＾－１３ｇ／ｍＬＡｇ线性浓度范围为１．０×１０＾－１２～１．０×１０＾－６ｇ／ｍＬＡｇ对４×１０＾－１１ｇ／ｍＬＡｇ（Ｉ）溶液连续１１次测定的ＲＳＤ≤３．５％，用于环境水和岩矿中银的     

新银盐光度法测定磷酸氢钙中的微量砷

以硝酸银－乙酸－聚忆烯醇－乙醇作为砷化氢吸收液,Ｚｎ－ＫＩ－ＳｎＣｌ２为还原体系的新银盐光度法测定了磷酸氢钼中的微量砷。Ａｓ＾２－含量在０－７．５μｇ／５ｍＬ范围内服从比耳定律。应用于磷酸氢钙样品中Ａｓ呈测定,回收率９６－１０３％,方法检出限为２．８８×１０＾－６ｇ／Ｌ,ＲＳＤ为０．９４－５．５０％,测定结果与标准方法基本一致。     

催化动力学光度法测定痕量苯酚

研究了在硫酸介质中苯酚对Ｉ＾－１催化Ｃｅ＾４＋－Ａｓ（Ⅲ）反应的抑制作用及其动力学条件。建立了用催化动力这光度法测定痕量苯酚的新方法，结果表明，在０．００１ｍｏｌ／ＬＣｅ（ＳＯ４）２，０．００１２５ｍｏｌ／Ｌ，Ａｓ２Ｏ３，０．０１ｍｇ／Ｌ，ＫＩ，０．０１２５ｍｏｌ／Ｌ，Ｈ２ＳＯ４和０．１３％（ｗ／ｖ）ＮａＣｌ溶液中测定苯酚，其表面摩尔吸光系数为２．１×１０＾５Ｌ．ｍｏｌ＾－１．ｃｍ＾－１，线性范围     

大黄酚的电化学行为及其应用研究

大黄酚在０．１５ｍｏｌ／Ｌ ＨＡｃ－ＮａＡｃ（ｐＨ４．９）底液中，出现一灵敏的示波极谱导数峰，峰电位为－０．４５Ｖ（ｖｓ，ＳＣＥ），峰电流与大黄酚浓度在２．０×１０＾－７－５．０×１０＾－６ｍｏｌ／Ｌ范围内成线性关系，检测限为２．０×１０＾－６ｍｏｌ／Ｌ。用于生药大黄中大黄酚的测定，回收率为９２．４％－１０８．４％。用多种电化学手段研究体系的电化学行为，测得电极反应电子数ｎ＝２。体系具有吸附性，并     

诺氟沙星离子选择性电极的研制和应用

研究了诺氟沙星选择电极的制备方法,将该电极应用于诺氟沙星胶囊制剂的测定。在ＮａＡｃ－ＨＡｃ（ｐＨ４．０）底液中,电极响应的线性范围为１．０×１０＾－４￣１．０×１０＾－２ｍｏｌ·Ｌ＾－１,七次测定的标示量百分含量的平均值为９４％,与药典法测定结果基本一致,相对标准偏差为１．０％。     

新催化动力学光度法测定痕量铝

根据ＡＩ＾３对ＫＢｒＯ３氧化Ｂａｎｇ花青褪色的催化行为,建立了测定痕量铝的催化动力学动力学分析方法。本法线性范围为０～１６０ｎｇ．ｍＬ＾－１,检出限为１．０ｎｇ．ｍＬ＾－１。除Ｃｕ＾２＋、Ｆｅ＾３＋、Ｃｒ（Ⅵ）外,其余离子均不影响测定。Ｆｅ＾３＋和Ｃｕ＾２＋、Ｃｒ（Ⅵ）的干扰可分别有效消除。测定了人发、茶叶和不中的,加标回收率为９８．４％～１０２％,ＲＳＤ为１．３％～２．１％（ｎ＝６）。     

抑制动力学分析法测定痕量铈

１引言研究了铈（Ⅲ）阻抑Ｈ２Ｏ２氧化水杨基荧光酮（ＳＡＦ）褪色的反应。反应对铈（Ⅲ）为一级反应，表观活化能为２８．７５ｋＪ／ｍｏｌ。据此建立了测定痕量铈的动力学分析法。测定条件为：ＳＡＦ：４．０ｘ１０－５ｍｏｌ／Ｌ，Ｈ２Ｏ２：０．０１０％，ＮａＯＨ：２．０ｘ１０－２ｍｏｌ／Ｌ，５０℃。线性范围０．０４～０．４４ｍｇ／Ｌ，检测限为０．０２ｍｇ／Ｌ。当溶液中的铈含量为０．１６ｍｇ／Ｌ时，３～８倍量的轻稀土，５～１１倍量的重稀土及同倍量铀和钍不干扰测定。２实验部分２．１试剂和仪器铈（Ⅲ）标准溶液：２０…     

锡钨杂多酸—耐尔蓝光度法测定纳克量易

本文报道一个光度法测定纳克量锡的新方法,在聚乙烯醇（ＰＶＡ）存在下锡与钨酸盐和耐尔蓝（ＮＢ）反应形成离子缔合物,离子缔合物的最大吸收位于５８０ｎｍ,表现摩尔吸光系数ε值２．９５×１０＾７Ｌ·ｍｏｌ＾－１·ｃｍ＾－１。服从比耳定律范围０－２．０μｇ／Ｌ,检出限（３σ）０．０８３μｇ／Ｌ,对２．０μｇ／Ｌ锡测定的ＲＳＤ为２１．４２％,离子缔合物至少稳定７２ｈ。考察了４０多种共存离子的影响,大多数常见元     

N-四氢苯并噻唑亚胺Schiff碱的化学发光测定

新合成的噻唑类Ｓｃｈｉｆｆ碱Ｎ－２（２－四氢苯并噻唑）－２－羟基苯甲亚胺及类似化合物与Ｃｅ＾４＋反应可产生微弱的化学发光,使用增敏剂奎宁可使发光显著增强,研究其发光反应动力学曲线、荧光光谱、化学发光光谱以及Ｓｃｈｉｆｆ碱与Ｃｅ＾４＋混合前后紫外可见吸收光谱的变化,确定子发生反应的官能团,讨论了发光反应的机理。考察了奎宁存在下Ｓｃｈｉｆｆ碱与Ｃｅ＾４＋化学发光反应条件及共存物质对发光强度的影响,建立了流动注射化学发光测定Ｓｃｈｉｆｆ碱的方法。该法线性范围为２．０＊１０＾－７－１．０＊１０＾－４ｍｏｌ／Ｌ检出限为８．０＊１０＾－８ｍｏｌ／Ｌ,化学发光测定Ｓｃｈｉｆｆ碱的方法,该法线性范围为２．０＊１０＾－７－１．０＊１０＾－４ｍｏｌ／Ｌ,检出限为８．０＊１０＾－８ｍｏｌ／Ｌ,对２．０＊１０＾－６ｍｏｌ／Ｌ噻唑类Ｓdi     

氨基酸-稳定同位素稀释质谱法用于合成肽段准确含量分析

建立了氨基酸同位素稀释液相色谱-串联质谱法准确测定合成肽段绝对含量的方法。实验中对合成肽段的纯度进行了表征,色谱纯度表征结果为99%以上,质谱纯度为90%以上。在肽段溶液中加入13C标记的氨基酸后进行酸溶液水解时间的优化,水解后的氨基酸直接经液相色谱分离和质谱检测,结果表明肽段中的被测氨基酸在150 ℃、6 mol/L HCl溶液水解4～6 h就可以达到水解平衡。每个肽段选择两个或两个以上的被测氨基酸,测得随机选择的5种合成肽段的绝对含量为62.07%～88.18%,测定结果的相对标准偏差小于8%,相对误差小于5%,均满足定量要求。除常用的被测氨基酸苯丙氨酸、缬氨酸、异亮氨酸外,还考察了选择赖氨酸和精氨酸作为被测氨基酸的可行性,实验结果表明增加精氨酸为被测氨基酸是可行的,从而进一步增加了方法的普适性。该方法的建立避免了色谱法定量时氨基酸衍生化处理带来的副反应影响及操作繁琐等问题,提高了肽段含量测定的准确度和精密度,为肽段含量的准确测定提供了一种新的方法。     

Determination of the Concentrations of Binary Mixtures of Glycerine and Water by a Transient Method

The conductivities of binary mixtures of glycerine and water were measured at 20°C by means of a transient method. The equation describing the correlation between concentration and thermal conductivity was determined. The equation can be used for determining concentrations in mixtures. The results show that (1) the error in the determination of the molar concentration of water in mixtures is less than 1%, (2) the time of measurement is 1 s, (3) this method can be used for on-line analysis in production control. This revised version was published online in July 2006 with corrections to the Cover Date.     

用ICP-AES法测定首饰金的成分

本文报道采用ICP-AES法直接同时测定首饰金中合金无素及主要杂质元素含量,通过计算求得金含量。确定了仪器的最佳工作条件,进行了干扰试验。方法适用于18k～99.99%成色的首饰金。测定的RSD为<0.01%(对于高纯度金祥n=10)～0.2%(对于10k金样n=10)之间,分析结果表明,方法准确、快速、简便且样品消耗量少。     

Peak area measurement of severely overlapped pairs

Summary Based on the ratio of two apparent heights and an empirical correction factor, a method is presented for quantitation of peak areas of severely overlapped pairs. This method can be applied to a wide range of area ratios and peak asymmetries, provided there exists a clear and precise valley-except for shoulder peaks. The relative errors of the first peak are usually within ±3% and theoretical relative error limits are −7.0% to +5.5%. Peak asymmetry of a severely overlapped pair can be determined using the ratio of the front half-width to the rear half-width at 10% peak height of an overlapping profile. The asymmetry so determined is an apparent one and the relative errors are −4% to +5.3% for peaks with 90% relative valley, depending on area ratio, degree of overlap and asymmetry. An empirical area equation for the first peak involving area ratio, asymmetry, resolution and the area measured by a perpendicular drop algorithm is also developed.     

镍-二甲酚橙-溴化十六烷基三甲铵动力学光度法测定镍

研究了Ni2+与二甲酚橙及溴化十六烷基三甲铵形成三元络合物的反应特性，测定了反应级数和表观活化能．基于该络合反应速率较小的特性，采用对数外推法计算机处理数据，建立了停流－动力学测定Ni2+的新方法．大多数元素的干扰均可用动力学方法消除，应用于镍矿等实样中镍的测定，结果满意，其相对标准偏差小于3％。     

Development of a method for direct determination of solids as thin films by energy dispersive X-ray fluorescence analysis

Solid samples can be analysed as without a prior decomposition step, if they are pulverized and then embedded in a thin layer of a cold-setting polymer. This method is very appropriate for materials which are difficult to decompose or which can be easily contaminated. The sample components are evenly distributed in a thin layer, which improves considerably the signal-tonoise-ratio, and this leads to a decrease of the limits of detection. The reproducibility of the method was tested with cobalt oxide and yttrium oxide and also a mixture of these with silver oxide and manganese dioxide. Between 20 and 60 ng of these elements can be determined without difficulty, with a precision of ± 2–4%. The correlation coefficients found for the calibration graphs were between 0.994 and 0.999.     

无需待测化合物标准样品便可测定校正因子

 根据色谱峰面积、校正因子和待测组分含量的关系，应用Ｌｅｖｅｎｂｅｒｇ－Ｍａｒｑｕａｒｄｔ方法对气相色谱分析数据进行最优化计算，可在缺乏待测组分标准样品的条件下测定相应的校正因子。分别测定了甲苯－氯苯、二乙氧基甲烷－乙酸乙酯和二乙氧基甲烷－乙醇－水等３个体系中各组分的相对校正因子。结果表明：化合物校正因子的测定值与相应文献值的相对偏差小于３％。根据实验结果进一步讨论了方法的适用范围以及进行测定所需样品的数目。     

快速溶剂萃取-气相色谱/质谱法分析血液中的甲卡西酮

建立血液中甲卡西酮快速溶剂萃取（ASE）-气相色谱/质谱（GC/ MS）分析的新方法. 通过优化 ASE 的萃取条件（溶剂、温度及时间）,对血液中的甲卡西酮进行有效提取,之后用 GC/ MS 进行定性、定量分析. 方法检出限为0. 02 mg / L,定量限为0. 1 mg / L. 血液中甲卡西酮在0. 5、1. 0 和2. 0 mg / L 3 个添加水平的平均回收率在96. 70% ~99. 27%之间,甲卡西酮在0. 1 ~ 50 mg / L 的浓度范围内线性良好. 方法快速、简便、高效且操作自动化,适用于血液中甲卡西酮的检验鉴定.     

Study of Spectrophotometric Determination of Amoxicillin Using Sodium 1,2‐Naphthoquinone‐4‐Sulfonate as the Chemical Derivative Chromogenic Reagent

Abstract

A simple and sensitive spectrophotometric method is described for determination of amoxicillin. The method is based on a nucleophilic substitution reaction to measure the pink compound produced by the reaction of amoxicillin with sodium 1,2‐naphthoquinone‐4‐sulfonate in pH 9.00 buffer solution. The stoichiometric ratio of the compound is 1:1, and its maximum absorption wavelength is at 468 nm, ε=3.91×10³ L · mol^?1 · cm^?1. The Beer's law is obeyed in the range of 0.8–120 µg · mL^?1 of amoxicillin. The linear regression equation is A=0.041239+0.22128 C, with 0.9994 of a linear regression correlation coefficient. The detection limit is 2.0 µg · mL^?1, and average recovery is over 98.5%. This paper further optimizes the determination of amoxcillin compared to the previous methods, and the kinetic property and reaction mechanism are studied intensively. This proposed method has been successfully applied to the determination of amoxicillin in tablets and capsules. The results obtained by this method agreed well with those by the official method high pressure liquid chromatography (HPLC).