摘要:

The d.c. anodic stripping voltammetry method has been used to investigate the effect of organic substances simulating the composition of natural waters on the results of determination of concentration levels of copper, lead and cadmium. The response, sensitivity and concentration (the latter determined by the standard additions method) have been used as sources of information. In the presence of enzymes, fulvic acids, humic acids and polyethylene glycol all these three parameters change in the case of determination of copper and lead, making the results unreliable. The determination of cadmium concentration is not hampered by the said organic substances.

ISSN:0003-2719    

DOI:10.1080/00032718508068756

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

The polarographic reouction of quinoline-4-alochyde is studied in different supperting electrolytes and at different pH values. The compound is reduced through a two one-electron irreversible steps in both acid and alkaline media. The nature of the obtained reduction waves, mechanism of the electrode reaction and kinetic parameters has been considered.

ISSN:0003-2719    

DOI:10.1080/00032718508068757

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

A divalent ion-selective electrode in combination with a single junction reference electrode was used to determine the stability constants of calcium, magnesium and zinc gallate. All measurements were carried out at 25[ddot]C, constant ionic strength of 0.1M and with the pH adjusted to pH8 using a Tris-HCl buffer. Direct potentiometric titration of the metal ion solution with solutions of gallic acid showed a break when the metal-ligand ratio was 2:1. Using the concentration of free metal ion determined by direct measurements, the experimental results indicated binuclear complex formation. Conditional stability constants were calculated. From the experimentally determined dissociation constants for gallic acid (pK14.4, pK28.6, pK311.2, pK412) the calculated stability constants for the metal gallate complexes gave the following log K values: Ca 11.45: Mg 10.70: Zn 11.38. The ion-selective electrode provides a Convenient and accurate method for the determination of stability constants in aqueous solutions.

ISSN:0003-2719    

DOI:10.1080/00032718508068758

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

The oxidation of species derived from adsorption of methanol, formic acid and reduced CO2on platinized platinum electrodes with different roughness factor by some inorganic oxidants has been studied using electrochemical and radiochemical methods. It was found that the roughness of the electrode and the type of the oxidant as well as the adsorbed species have some influence on the reaction course.

ISSN:0003-2719    

DOI:10.1080/00032718508068759

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

Ternary compleres of cadmium (II) with succinate (Succ) as primary ligand and trimethylenediamine (TMDA) as secondary ligand have been studied using differential pulse polarography. Schaap and McMasters treatment reveals the presence of three mixed complexes with stoichiometries 1:1:1, 1:1:2 and 1:2:1. The reduction is reversible and diffusion-controlled. The stability constants of mixed ligand complexes were calculated atatistically using watters method and compared with the observed values.

ISSN:0003-2719    

DOI:10.1080/00032718508068760

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

A method is described for the analysis of phosphorus in geological samples involving the decomposition of the sample with hydrofluoric acid in a quartz tube and the measurement of phosphate ion concentration using an ion chromatograph (Dionex 10) with an anion separator column (Wescan anion 269-001). The detection limit is between 0.05-0.5% P2O5in the original sample. Multiple analyses of eight U.S.G.S. standard rocks yielded a relative standard deviation range between 2.37-16.67%. In excess of 15 samples can be analyzed in an 8 hour day.

ISSN:0003-2719    

DOI:10.1080/00032718508068761

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

Thiols are generally amenable to gas chromatographic analysis, When thiophenol is analyzed by gas chromatography-mass spectrometry, however, its mass spectrum also shows the molecular ion for dipheny 1 disulfide. This paper reports a systematic investigation establishing that the oxidation of thiophenol to dipheny1 disulfide takes place in the GC/MS interface and is affected by heat. Similar phenomena are also reported forp-chlorothiophenol, cyclohexyl mercaptan, andn-hexyl mercaptan.

ISSN:0003-2719    

DOI:10.1080/00032718508068762

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

A reduction-aeration method is optimized for the analysis of mercury at the ng.I−1-level in drinking-water. The parameters investigated are: the aeration time, the flow rate of the aeration-gas, the type of gas distributor, the amount of reductant and the mercury concentration. To improve the sensitivity, the mercury aerated is preconcentrated on a gold-coated quartz-sand absorber which is analysed by thermal desorption and CVAAS. In this way, the interference by water vapour is avoided and the calibration is simplified.

ISSN:0003-2719    

DOI:10.1080/00032718508068763

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

A method for sampling and analysis of airborne acetone cyanohydrin is described. The analyte is collected on Porapak QS, a silylated styrene-divinylbenzene porous polymer. Samples are desorbed with ethyl acetate and analyzed by gas chromatography using a nitrogen-specific detector and a teflon column packed with 5% OV-17 on Chromosorb T. The detection limit is estimated to be 0.1 μg/mL acetone cyanohydrin in ethyl acetate. The method was tested by evaporating from 1.0 to 50 μg of the analyte onto sorbent beds of Porapak QS and exposing the samples to a humidified airstream for 15 min. Quantitative recovery was obtained for samples stored for one day at ambient temperature or for seven days if the samples were refrigerated immediately after collection.

ISSN:0003-2719    

DOI:10.1080/00032718508068764

出版商:Taylor & Francis Group    

年代:1985

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:10.1080/00032718508068755

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor