摘要:

The influence of some precipitating and complexing agents on the function of Pb(II)-sensitive electrode was studied. On the basis of the experimental findings, procedures were worked out for determining oxalate, phosphate, chromate, nitrilotriacetic acid (NTA), sodium diethyldithiocarbamate (NaDDC), and diethylenetetraamine penta-acetic acid (DTPA) with a standard Pb(II) solution as a titrant and a Pb(II), -sensitive electrode as a detector. The reverse titration of Pb(II), with any of these agents could also be done.

ISSN:0003-2719    

DOI:10.1080/00032718108081460

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Electrochemical caracteristics of 2-mercaptopyridine-5-carboxylic acid and its methylic ester have been determined using recent polarographic techniques. Measurements have been carried out as a function of parameters such as frequency, others surimposed signals and as a function of concentration and pH. Results are compared to those obtained for selectively methylated on sulfur or nitrogen atoms derivatives. Interpretations of the data are given. The optimal conditions for a quantitative determination by D.C. and differential pulse polarography are fixed.

ISSN:0003-2719    

DOI:10.1080/00032718108081461

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Paper chromatographic separations of 34 organic acids on calcium carbonate and calcium sulphate impregnated paper has been developed. Tricarboxylic acids, dicarboxylic acids, amino acids, and keto acids and their derivatives can be separated in simple solvents such as acetone, ethanol, water, aqueous sodium chloride, ammonium chloride and calcium nitrate. Important separations achieved are: Adipic from maleic and malonic, cis-aconitic from I-cystine and nicotinic, citric or tartaric from ascorbic, gallic, malic and salicylic, I-aspartic from arginine-HCl, fumaric and glutamic, barbituric from hippuric and α-ketoglutaric, benzoic from ρ- & m-nitrobenzoic and cis-aconitic from trans-aconitic.

ISSN:0003-2719    

DOI:10.1080/00032718108081462

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

The vapour pressure (10−3to 10 mmHg) of n alkanes (hexadecan to octacosan) and a serie of polyethylene glycols (molecular weight 50 to 400) have been determined by the inert gas saturation technique. The relation between P and the number of carbon atoms or the temperature are given. The method can be used to identify fractions in liquid chromatography.

ISSN:0003-2719    

DOI:10.1080/00032718108081463

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

A gas chromatographic method for the determination of trace amounts of some chloro- and nitrophenols is reported. Direct acetylation of chloro- and nitrophenols is carried out by adding acetic anhydride to large volumes of an alkaline aqueous solution of phenols. The stable acetate esters formed improve chromatographic characteristics and also provide for near quantitative extraction using small volumes of methylene chloride. Relative retention times of nine acetates of phenols on 1% SP-1240 A are reported and seven derivatives have been separated. The increased extraction efficiency, short extraction time and small volume of organic solvent used are some of the attractive features of this method in comparison to currently used methods.

ISSN:0003-2719    

DOI:10.1080/00032718108081464

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

HPLC-ECD and HPLC-GC-ECD instrumentation can be conveniently applied to the trace analysis of a wide variety of explosive materials in complex matrices. Limits of detection, sensitivity, and linearity plots for a number of standard explosives have been determined. These methods have now been applied to the real world analysis of explosives in post-blast residue debris, and the overall methods have been compared and confirmed via more conventional TLC approaches.

ISSN:0003-2719    

DOI:10.1080/00032718108081465

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

p-Nitrosodiphenylamine as a representative of nitrosoamine group was tested as a new reagent for the spectrophotometric determination of SO2. A mixture containing: p-nitrosodiphenylamine, formaldehyde, HCl, di-methylformamide and water was added to the aqueous test solutions of sulphites forming after 5 min, a blue complex with Λmax=675 nm stable for one hour. The Lambert-Beer law was obeyed in the 0 to 50 /ug SO2/cm3range. Molar absorptivity was equal to 2000 and the specific absorption was 0.062. The investigations should lead to search for other reagents from the nitrosoamine group suitable for this purpose.

ISSN:0003-2719    

DOI:10.1080/00032718108081466

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

End-point detection, in titrations involving precipitation, neutralization and complexation reactions, was accomplished by means of ebulliometric measurements with an average error of 1.6%. The titration curves consisted of straight lines with different slopes, before and after the end point. Theoretical curves were derived which show that the slopes depend on the kind and on the order of addition of reagents.

ISSN:0003-2719    

DOI:10.1080/00032718108081467

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

This is a scanned image of the original Editorial Board page(s) for this issue.

ISSN:0003-2719    

DOI:10.1080/00032718108081459

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor