Catalytic Photometric Determination of Selenium by Flow Injection Analysis

A method is developed for the determination of trace amounts of selenium by flow injection analysis based on the catalytic effect of this element. Catalytic enhancement by selenium for the reduction of picrate ion by sodium sulfide was used and photometrically measured at the wavelength, 470nm. Optimum conditions were determined for temperature, pH, the concentrations of picrate and sodium sulfide, and also the conditions of the flow system; injection of sample volume, flow rate and mixing coil length. With these conditions a good linear relationship was obtained for selenium in the range from 0.1 ppm to 1.0ppm and the detection limit was about 5ppb (two times of the noise). Interference by the diverse ions can be avoided with the use of a precolumn cation exchanger (Dowex 50) and by masking with EDTA in the conditional stream.     

Optimisation of a Flow Injection System with a Piezoelectric Quartz Crystal Detector for the Determination of Inorganic Mercury

ABSTRACT

A new method combining flow injection methodology with quartz crystal microbalance (QCM) detection is proposed for inorganic mercury analysis. A modified simplex method is used in order to maximise the observed analytical signals (crystal frequency decrease). Six parameters were optimised: the concentration of the acidic carrier solution, the lengths of the sample loop and mixing coil, and the flow rates of the sample carrier, the reductant stream (SnCl₂), and the carrier of the mercury vapour (N₂). An increase of 18% in the signal of the centroid of the calibration line was achieved, as well as an increase in the sensitivity from 290 Hz μg^? to 313 Hz μg^?. Following the proposed procedure, detection limits of 47 μg L^? of inorganic mercury were found for sample volumes of 0.5 mL.     

Indirect Spectrophotometric Determination of Fluoride In Water With Zirconium-Spadns By Flow Injection Analysis

Abstract

The zirconium-SPADNS method for the determination of fluoride based on the effect of fluoride ion on the color system (Zr-SPADNS), has been adapted to the continuous flow spectrophotometry. A manifold consisting of two lines was used. the decrease in the absorbance of Zr-SPADNS reagent at 590 nm is linear with fluoride concentration in the range 0.00-3.5 ppm. the method has a detection limit of 0.02 ppm fluoride. At a sampling rate of 50 determinations per hour, the precision was about 1% relative standard deviation. the method is applied to the determination of fluoride in natural water samples. the good agreement between the results obtained by this method and those obtained by a potentiometric method using a fluoride ion-selective electrode, show that the new method is potentially suitable for routine analysis. the effects of reaction conditions, flow parameters, and interferences on the FIA-spectrophotometric signals are reported. amount of interfering ion is present in quantity great enough to produce an error of 0.1 ppm or more, the sample must be distilled¹⁷     

气体扩散法测氨中几种流动注射扩展线性范围方式的比较及发酵液中氨态氮的测定

本文以气体扩散法测氨为例，比较了三种流动注射扩展线性范围方法的性能；讨论了影响分析精度的因素。把微升进样在线稀释技术同气体扩散光度法结合，测定了农药发酵液中氨态氮的含量。方法的回收率为９３—１０６％，每小时可分析６０—８０个样。     

Spectropotometric Determination of Cyanide by Flow Injection Analysis

Abstract

The flow injection technique is shown to provide fast, reliable, and sensitive determination of cyanide. Spectrophotometric detection in the ultraviolet region at 267 nm was used for measuring the absorbance of tetracyanonickelate (II) complex ion. The nickel carrier stream and the sample solutions were buffered at pH 10 (ammoniacal buffer). The method has a detection limit of 0.2 ppm cyanide. At a sampling rate of 90 samples per hour, with 60 μl sample injections, high reproducibility of measurements was achieved, with about 1% relative standard deviation. The effects of sample volume, flow rate, coil length, and anions interference on the FIA-spectrophotometeric signals are reported.     

Simultaneous Spectrophotometric Determination of Silicate and Phosphate by Flow Injection Analysis

Abstract

A method is reported for the simultaneous determination of phosphate and silicate by flow injection analysis based on the different rate of formation of the heteromolybdic acids of the two anions. Measurements are based on the colour of the ion-pairs formed between the said molybdic acids and Rhodamine B. The method allows the determination of the two anions at a rate of 20 samples/h over the ranges 0.05–2.5 ppm (phosphate) and 0.8–15 ppm (silicate), which allows application to a variety of waters.     

水杨基荧光酮胶束增敏流动注射分光光度法测定微量锗

本文将锗一水杨基荧光酮一溴化十六烷基三甲基铵胶束五色体系应用于流动注射分析，建立了测定微量锗的快速方法。方法采用单通道流路及合并带流路进行试验。对有关的管路参数及试剂浓度等影响因素进行了探讨。优化的流动注射分析体系对锗的检测灵敏度高、重现性好。方法用于混合成试样及有机锗生物制品中锗的测定，结果满意。     

流动注射—吐温40化学发光新体系测定贵金属冶金物料中微量铱

本文研究了吐温４０－ＫＯＨ－Ｈ２Ｏ２－Ｉｒ化学发光新体系，采用流动注射进样技术，建立了测定铱的新的化学发光分析法，检测限为１．１×１０＾－１３ｇ／Ｌ；线性范围为每ｍＬ１．０×１０＾－９－１．０×１０＾－５ｇ。经离子交换分离Ａｕ和Ｏｓ离子后，测定贵金属冶金物料中微量铱，结果满意。     

停流流动注射分析同时测定碘离子和亚硝酸根的研究

基于铁（Ⅲ）－硫氰酸根络合物褪色动力学反应，利用流动注射分析停流技术，建立了流动注射动力学分析法同时测定碘离子和亚硝酸根离子的新方法，方法对碘离子的线性范围为２×１０＾－－１．６×１０－４ｍｏｌ／Ｌ，对亚硝酸根的线性范围为４×１０＾－７－１×１０ｍｏｌ／Ｌ。应用于全成混合液中碘离子和亚硝酸根的测定，结果满意。     

尿中肌酐的流动注射分析

本文提出了一种简便快速的尿中肌酐的测定方法。采用空气整段间隔试样带的流动注射分析体系,在非化学反应平衡的条件下测定,尿样不经手工稀释可直接用于测定。测样频率每小时为90次,相对标准偏差为1.5%。     

化学发光—流动注射—胶束增敏连续测定钴铬研究

基于钴（Ⅱ）和铬（Ⅲ）对鲁米诺－过氧化氢化学发光反应均有催化作用，加入ＣＴＭＡＢ能明显提高发光的信噪比，可测定亚纳克量的钴和铬，加入ＥＤＴＡ掩蔽钴（Ⅱ）测得铬（Ⅲ）量，再由钴和铬总量求得钴（Ⅱ）量，实现钴和铬的不经分离而流动注射连续测定。此法线性范围宽达４个数量级（１０－１１～１０－７ｇ／ｍＬ），检测下限低（Ｃｏ２＋１．２×１０－１１ｇ／ｍＬ，Ｃｒ３＋１．０×１０－１１ｇ／ｍＬ），再现性好，工效高（１２０个样品／ｈ），用于三种矿泉水中痕量钴（Ⅱ）、铬（Ⅲ）连续测定，结果良好     

吗啡的流动注射分光光度法分析研究

本文建立了吗啡的流动注射分光光度分析法。在优化条件下,线性检测范围为30～700μg/ml,回归方程为h=0.0250+1.74×10~(-3)C,相关系数为0.9999,并用于吗啡样品的分析。回收率为99.9％,相对标准偏差为0.43％,样品分析速度为240次/小时。     

Batch and Flow Injection Fluorimetric Determination of Fluoxetine

Abstract

A method for the fluorimetric determination of fluoxetine in continuous and discontinuous systems is reported. The method is based on the hydrolysis of fluoxetine in acid medium. The fluorescent product has a spectrum with excitation and emission maxima at 253 and 306 nm, respectively. The method was applied to the determination of fluoxetine in pharmaceutical products.     

流动注射—分光光度法测定植物中钼

本文将流动注射分析(FIA)引入Mo-SCN~--RhB三元缔合体系测定痕量Mo。不需萃取,反应迅速,重现性好。0～1.6μg/ml Mo符合比耳定律,检测限0.02μg/ml。用预混线圈R_1可克服Fe~(3+)等元素与SCN~-络合的干扰。测定了植物中Mo,结果满意。     

流动注射光度法测定阳极泥中微量锇

目前,流动注射分析已广泛应用于许多元素和物质的快速测定。但锇的流动注射分析方法至今未见报道。本文根据γ-酸(7-氨基-1-萘酚-3-磺酸)被空气中的氧氧化后生成血红色醌的反应能被微量Os(Ⅷ)催化的原理,在文献的基础上,采用自制的集成微管道,建立了用合并带-停流技术测定Os(Ⅶ)的流动注射分析方法。该方法具有快速简便、节省试剂、精密     

Application of Flow Injection Method for the Determination of Thioridazine

Abstract

A simple flow-injection spectrophotometric method for the determination of thioridazine is described. The method is based on the oxidation of thioridazine with phosphotungstic acid in hydrochloric acidic media. Concentrations of thioridazine in the range 10 – 60 ppm are determined with a relative standard deviation of 1.1%. The method was applied to the determination of thioridazine in pharmaceutical formulations.     

Determination of Phenolic Compounds and Coumarins in Sugar Cane Spirit Aged in Different Species of Wood

The identities and quantities of the phenolic compounds and coumarins in twelve samples of sugar cane spirit aged in Quercus sp., Amburana cearensis, Cariniana legalis, Castanea sativa Mill, Ocotea sp., Cotyledon orbiculata L., and Hymenaea sp. casks were determined. These compounds have a direct influence on the sensory characteristics of aged beverages; some of them are considered to be markers for the aging process. The analysis of phenolic compounds was performed by HPLC. Solid phase extraction (SPE) was also used for the determination of coumarins. The concentrations of the principal compounds extracted varied according to the species of wood. The concentrations of total phenolic compounds ranged from 0.08 for a sample stored in a 4000-L jatobá barrel for a period of six months to 40.9 mg · L^?1 for a sample aged in a 50000-L oak barrel for a period of 48 months. The use of the SPE technique removed interfering compounds from the samples, thereby improving the detection of coumarin.     

流动注射胶束增溶分光光度法同时测定镁砖中微量铁铝

本文研究了铁铝－ＣＡＳ－乳化剂ＯＰ胶束增溶体系的ＦＩＡ－光度法时测定镁砖中微量铁铝，该法操作简便，快速可靠，进样频率４５样次／ｈ，ＲＳＤ＜３．４％和５．８％。结果令人满意。     

间氯偶氮安替比林流动注射分析测定药物及水中钙

基于间氯偶氮安替比林可与钙在碱性介质中形成灵敏的兰色络合物这一显色反应，本文在自行组装的带微型计算机的流动注射分析仪上，以分光光度计作检测器，建立了测定微量钙的流动注射分光光度法。最佳显色反应条件：０．０８ｍｏｌ／Ｌ ＮａＯＨ－０．０１２％显色剂２．０％三乙醇胺溶液，测定波长为６３０ｎｍ。以三乙醇胺为掩蔽剂，方法选择性较高。钙的线性范围为１．０￣１５．０μｇ／ｍｌ，检测限０．５μｇ／ｍｌ，进样频率