Capillary Electrophoretic Determination of Tetramethylthiuram Disulphide (Thiram)

SUMMARY

A simple and sensitive capillary electrophoretic method was developed for the separation and determination of Thiram in boric acid buffer by direct UV absorbance detection at λ = 254 nm. The separation behaviour of Thiram from Nabam was studied and it is dependent on pH and the nature of the buffer. The detection limit (S/N = 3) is 0.5 μg/ml for Thiram. The method was successfully applied to the analysis of wheat samples spiked with Thiram.     

The Simultaneous Spectrophotometric Determination of Osmium and Ruthenium

Abstract

A spectrophotometric procedure is described for the simultaneous determination of osmium and ruthenium in the form of bromo complexes. It was found that a blue ruthenium-thiourea complex could be formed in 6.7 M HBr solutions while the osmium could be maintained as the hexabromoosmate complex. Absorption maxima were at 620 μ for the ruthenium complex and at 446 μ for the osmium complex. Molar absorptivities for the ruthenium complex were 2.47 × 10³ at 620 μ and 763 at 446 μ. For the osmium complex molar absorptivities were 328 at 620 μ and 6.81 × 10³ at 446 μ. The method is useable over the range of 5 to 30 ppm with an absolute error of = 1 ppm over the range. Other platinum metals interfere.     

催化动力学分光光度法测定痕量锇

在磷酸介质及加热条件下 ,锇 对KBrO3氧化二氨替比林基 对二甲氨基苯基甲烷 (DAMAM)显色反应有强烈的催化作用 ,由此建立了测定痕量锇的催化动力学分光光度分析法。体系催化反应 (吸光度为A)和非催化反应 (吸光度为A0 )的最大吸收波长均为 5 4 0nm ,锇含量在 0～ 14 μg L范围内与 (A -A0 )呈线性关系 ,检出限为 1.82× 10 - 9g mL ,方法用于冶金产品和贵金属精矿中痕量锇的测定 ,结果满意     

乙基罗丹明B-高碘酸盐催化光度法测定锇

在０．００８ｍｏｌ／Ｌ硫酸介质和热水浴中,Ｏｓ（Ⅳ）催化高碘酸盐氧化乙基罗丹明Ｂ（ＥＲＢ）褪色,建立了灵敏催化光度法测定锇,Ｏｓ（Ⅳ）浓度在０￣８．８ｎｇ／ｍＬ范围成线性关系,检出限为０．０２６ｎｇ／ｍＬ,对６．０ｎｇ／ｍＬ Ｏｓ（Ⅳ）测定的相对标准偏差为１．８８％（ｎ＝１１）,催化反应对Ｏｓ（Ⅳ）、ＥＲＢ、ＫＩＯ和Ｈ２ＳＯ４分别为一级反应,表观活化能为２０５．７ｋＪ／ｍｏｌ。探讨了反应机理,研究     

Rapid Spectrophotometric Determination Of Osmium With Cyclohezane 1,3-Dione Bisthiosemicarbazone Monohydrochloride: Simultaneous Determination of Osmium and Platinum

Abstract

A simple, sensitive and rapid spectrophotometric method has been developed for the determination of osmium using cyclohexane 1,3-dione bisthiosemicarbazone mono-hydrochloride (1,3-CHDT.HCl). The method is based on the instantaneous colour reaction between 1,3-CHDT. HCl and osmium(VIII) in sodium acetate—acetic acid buffer medium (pH range 3–6). The osmium complex shows maximum absorbance at 375 nm and considerable absorbance at 510 nm. Although the complex formed between platinum(IV) and reagent (1,3-CHDT.HCl) shows maximum absorbance at 375 nm, it does not show any absorbance at 510 nm. Simultaneous determination of osmium and platinum is carried out when present alone and in presence of other foreign (associated) ions. Some physico-chemical and analytical characteristics of osmium and platinum complex are described. Interference of various foreign ions have studied and osmium is estimated selectively in the presence of constituents of platinum ores.     

Spectrophotometric Determination of Azide Ion Through Carbon Disulphide - Azide Reaction

Abstract

The azide ion can be converted quantitatively into 1,2,3,4, - thiatriazol - 5 - thiolate ion by treatment with carbon disulphide in aqueous ethanolic medium. The CS₂N₃ ^? concentration is measured spectrophotometrically at 321nm, where ?= 7. 8 × 10³ l mol^?1 cm^?1. The conditions outlined below provide a rapid, simple and precise method to determine the azide ion at the 8 μg/ml level.The influence of several foreign ions on the proposed method is also studied.     

Spectrophotometric Determination of Osmium at the PPB Level Using Pyrocatechol and Hydroxyamidine

Abstract

A sensitive method for the spectrophotometric determination of osmium at the ppb level is described. The method is based on the formation of a brown-coloured complex by heating the reaction mixture containing Os(VIII), pyrocatechol and a hydroxyamidine at pH 8.5 over a boiling water bath, with subsequent extraction of the coloured species into chloroform. The molar absorptivity of the coloured species with N-hydroxy-N,N′-diphenylbenzamidine is 3.95 × 10⁶ 1 mol^?1 cm^?1 at λ_max = 410 nm. The method is free from interferences for almost all ions tested.     

用8－氨基喹啉高选择性分光光度法测定痕量锇的研究

研究了用８－氨基喹啉在ｐＨ３．６２的ＨＡｃ－ＮａＡｃ缓冲溶液中测定痕量Ｏｓ（Ⅳ）的分光光度法。常见的非贵金属和贵金属离子不干扰测定，并且选择性较好。Ｏｓ（Ⅳ）与８－氨基喹啉的组成比为１：３，表观摩尔吸光系数ε_（６００）＝１．３×１０~５Ｌ／ｍｏｌ·ｃｍ。在０～１０μｇ／１０ｍＬ范围内符合比耳定律。合成样品分析结果良好。     

高碘酸盐氧化耐尔蓝动力学光度法测定锇

在硫酸介质和热水浴中 ,Os( )对高碘酸盐氧化耐尔蓝有催化作用。研究了反应速率对酸度、浓度、温度和离子强度的依赖关系 ,采用 0 .0 1 0mol/ L硫酸 ,反应的灵敏度随温度升高而增大 ,反应速率对反应混合物的离子强度依赖较小。线性范围为 0～ 0 .2 5μg/ 2 5m L;检出限为 8.0 2× 1 0 -5 μg/ m L;对质量浓度为 0 .1 0 μg/ 2 5m L 的 Os( )测定的相对标准偏差为 1 .0 2 % ( n=1 1 ) ;导出了催化反应的动力学方程 ;探讨了反应机理。4 0 0倍量以上常见金属离子不干扰锇的测定 ,1 0倍量以上的 Ru( )、Fe3 +有干扰。本法已用于贵金属冶金样品中锇的测定。     

Extraction and Spectrophotometric Determination of Diclofenac in Pharmaceuticals

A new simple, rapid and sensitive spectrophotometric method has been developed for the determination of diclofenac sodium (Dicl) in pharmaceutical preparations. This method is based on the reaction of diclofenac sodium with an analytical reagent 1,3,3‐trimethyl‐5‐thiocyanato‐2‐[3‐(1′,3′,3′‐trimethyl‐3′‐H‐indol‐2′‐ylidene)‐propenyl]‐indolium cloride (TIC) at pH 8.0‐11.0 and the extraction of ion associate colored complex. Optimal conditions for the complex formation between Dicl and TIC were studied. This ion associate complex (1:1) was detected and extracted with toluene and an absorption maximum at 566.2 nm against a blank reagent. The calibration graph was linear from 0.9‐11.0 μg/mL of diclofenac and the detection limit was 0.86 μg/mL.     

高碘酸盐氧化亚甲蓝动力学光度法测定痕量锇

以Ｏｓ（Ⅳ）催化高碘酸盐氧化亚甲蓝（ＭＢ）反应为基础提出了测定痕量锇的方法。在９０℃加热１４ｍｉｎ和６６０ｎｍ波长处采用固定时间法测定亚甲蓝吸收的降低,锇浓度在０～３．２μｇ／Ｌ范围呈线性关系,检了限为０．０２μｇ／Ｌ,对１．６μｇ／Ｌ Ｏｓ（Ⅳ）测定的ＲＳＤ为１．５６％（ｎ＝１１）,催化反应对Ｏｓ（Ⅳ）、ＭＢ、ＫＩＯ４和Ｈ２ＳＯ４均为一级反应,催化反应的表观活化能为８７．７２ＫＪ／ｍｏｌ,探讨了     

Extraction and Spectrophotometric Determination of Arsenic in the Environment

Abstract

A simple, sensitive and selective method for the determination of microamounts of arsenic (III) in the environment is described. Arsenic forms a yellow coloured complex with N-phenylbenzo-hydroxamic acid (PBHA) at pH 4.5-5.2 which can be extracted from chloroform. The effective molar absorptivity of As-PBHA extract is 1.1 × 1mol^?1cm^?1 at 410 nm. Many common ions associated with arsenic do not interfere. The effect of pH, reagent concentration and solvent is described. The arsenic in trace quantities is estimated in the industrial effluents, soil and glass samples.     

Determination of Platinum Metals III. An Extraction Spectrophotometaic Determination of Tetravalent Osmium

Abstract

A new spectrophotometry determination of Os(IV) has been developed, based on the formation of the [OsCl₆]^2? - 1-carb-ethoxypentadecyltrimethylammonium cation ion-associate extract-able into chloroform. The measurement is carried out at 340 or 376 nm. It is possible to determine 1.5 to 18.6 μg Os in 1 ml of the chloroform phase.     

在PVA存在下Os-SnCl_2-亮绿离子缔合体系的研究高纯镍中微量Os的测定

本文研究了Os-SnCl_2-PVA-亮绿离子缔合体系的显色反应,摩尔吸光系数ε_(434)为5.6×10~6L·mol~(-1)·cm~(-1),锇含量在0.1～0.7μg/25mL范围内遵守比耳定律,室温下显色后,吸光度在110min内稳定。研究了30种外来离子的影响,并进行了高纯镍中微量锇的测定。     

P507萃取分离-二甲酚橙光度法测定锆铪

本文用自合成的P507萃淋树脂对锆铪吸附特性进行研究,并对此树脂的离子交换柱性能进行了研究与测定;在此基础上,对不同配比锆铪混合液进行分离,作出了分离曲线,并采用二甲酚橙分光光度法对锆铪进行了测定.研究了干扰离子存在的允许量及树脂的使用寿命.     

Extraction and Spectrophotometric Determination of Antimony in the Environment:

A new sensitive method for the extraction and spectrophotometric determination of antimony in the environment is described. The antimony forms a greenish yellow coloured complex with N-phenylbenzohydroxamic acid (PBHA) at 4 M HCl which is extracted from chloroform.

The Sb-PBHA complex is back extracted in 0.01 M NH₄OH and then antimony is estimated with rhodamine B in 6 M HCl media. This bluish violet coloured complex is extractable in benzene. The maximum absorbance of the antimony rhodamine B complex is observed at 565 nm. The effects of acidity, reagent concentration and diverse ions are discussed. The method is applied to the trace determination of antimony in industrial effluents and natural resources.     

Extraction and Spectrophotometric Determination of Zirconium(IV)

Abstract

A sensitive and selective method for the extraction and spectrophotometric determination of Zr(IV) with N-p-chlorophenyl-3,4-,5-trimethoxycinnamohydroxamic acid (PTCHA) has been developed. The binary complex of Zr(IV)-PTCHA is extracted from 2–6 M HCl into chloroform, having a maximum absorbance at 385 nm; molar absorptivity 2.1 × 10⁴ 1 mol^?1 cm^?1. A ternary complex with xylenol orange (Zr-PTCHA-XO) have been studied in chloroform-ethanol media, which absorbs at 540 nm; molar absorptivity 4.3 × 10⁴ 1 mol^?1 cm^?1. The present method is applied for the analysis of zirconium in standard samples.     

在阳离子表面活性剂存在下锇与对硝基苯基荧光酮显色反应的研究

本文研究了在CTMAB存在下锇的分光光度测定新方法。络合物最大吸收峰位于570nm,摩尔吸光系数ε_(570)=1.0×10~5L·mol~(-1)·cm~(-1)。反应的pH为7.2～7.8。锇含量在0～7.0μg/10mL范围内服从比尔定律。锇在络合物中与p-NPF的摩尔比有1:1、1:2两种。采用蒸馏法锇能与所有金属离子分离,使该测定锇的方法具有专一性。用于人工合成样及矿样的分析结果满意。对显色反应机理进行了初步探讨。     

Extraction Spectrophotometric Determination of Vanadium in Industrial Waste Water

A new and simple extraction spectrophotometric method for the determination of vanadium(V) with KIO₄, N‐phenylbenzohydroxamic acid (PBHA) and crystal violet (CV), in industrial waste water samples is described. It is based on the extraction of mixed‐ligand complex V(V)‐IO₄^? ‐PBHA‐CV⁺ into chloroform solution over 2‐7 MHC1. The molar absorptivity of the complex is (7.20) × 10³1 mol^?1 cm^?1 at λ_max 535 nm. The detection limit of the method is 44 μg 1^?1 V. The linearity of the calibration curve is followed up to 6 μgmL^?1 in the organic solution with slope, intercept and correlation coefficient of 1.34 × 10^?1, 6.7 × 10^?3 and +0.99, respectively. This method enhances the sensitivity of the conventional PBHA method for the determination of vanadium, and is free from interferences of other metal ions commonly associated with vanadium. The method has been successfully tested for the determination of V in the industrial waste water samples.