摘要:

The effect of chloride on the bromide and iodide solid state precipitate electrodes is studied and selectivity constants calculated. The use of multiple linear regression analysis to determine the initial concentration of halide ions in solutions is studied and the resulting technique is used to determine fluoride, iodide and bromide in a geothermal-geopressured brine.

ISSN:0003-2719    

DOI:10.1080/00032718408065342

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

A method is described for the simultaneous flotation separation and determination of μg-levels of copper (II), nickel (II) and cobalt (II) in water. Copper, nickel and cobalt in a 1000-ml sample of water are coprecipitated with hydrated zirconium oxide at pH 9.1±0.1. The precipitate is floated with the aid of a surfactant solution and small air bubbles, separated and dissolved in dilute hydrochloric acid. The contents of these elements are determined by electrothermal atomic absorption spectrophotometry. The method is applied to the determination of low μg/1 levels of copper, nickel and cobalt in fresh water.

ISSN:0003-2719    

DOI:10.1080/00032718408065343

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Polycyclic aromatic hydrocarbons (PAHs) have been determined by GC/MS to be present on the inner surfaces of copper tubing as supplied by the manufactures. The PAHs presumably exist as byproducts of the manufacturing process. Concentrations of PAHs found ranged from 0.00021 to 0.17 mg/m of tubing.

ISSN:0003-2719    

DOI:10.1080/00032718408065344

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Since concentrations of trace elements in most natural waters seldom exceed the μg/L level, analysis of trace elements in natural waters by inductively coupled plasma emission spectrometry (ICP) requires a preconcentration procedure. The elements Ag, Bi, Cd, Co, Cu, Fe, Mo, Ni, Pb, Sn, V, W, and Zn were separated and concentrated from 500 mL of water by coprecipitating them with sodium dibenzyldithiocarbamate (NaDBDTC) using nickel or silver as a carrier. The precipitated trace elements were collected on a membrance filter, redissolved from the filter with hot nitric and hydrochloric acids, and analyzed using ICP. Recoveries for all the trace elements except tungsten exceeded 80%. Coprecipitation of trace elements with NaDBDTC eliminated the use of difficult-to-inject organic solvents, and NaDBDTC coprecipitated a wider array of trace elements than ammoniumpyrrolidinedithiocarbamate (APDC), another commonly used coprecipitate.

ISSN:0003-2719    

DOI:10.1080/00032718408065345

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

A statistical technique, components of variance analysis, was used to quantify three potential sources of variation in the determination of fluoride by ion chromatography (IC). The variance components due to sampling (2.09%) and oxygen bombings (1.47%) were found to be significant while the variance component due to IC repeats was only 0.272%. From these variance components the expected precision of various sampling and testing protocols was estimated. Graphical procedures were also used to visually analyze the experimental data.

ISSN:0003-2719    

DOI:10.1080/00032718408065346

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

In previous papers the authors reported that nonsuppressed ion chromatography using potassium hydroxide solution as an eluent was a very sensitive and effective method for the analysis of anions and that this method could be applied to the determination of anions in environmental water samples.

ISSN:0003-2719    

DOI:10.1080/00032718408065347

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

The solvent extraction methods for the separation of germanium are very limited. The carbon tetrachloride method had limited applications when large concentration of germanium was present(1). The extraction with tributyl phosphate was possible only in the presence of salting out agent(2). An attempt was made in this laboratory to separate germanium by reversed phase extraction chromatography from associated elements with tributyl phosphate as the stationary phase(3). No doubt this method permitted the separation of germanium from arsenic, indium, manganese, cobalt and zinc but it failed to separate germanium from commonly associated elements.

ISSN:0003-2719    

DOI:10.1080/00032718408065348

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Beelen and coworkers in the Netherlands recently reported that visible light enhanced the rate of selective oxidation of mercaptoethanol by dioxygen, catalyzed by cobalt (II) tetrasulfonated phthalocyanine (CoTSPC). The Dutch workers speculated that visible light promoted disaggregation of CoTSPC, producing more of the catalytically active monomer.

ISSN:0003-2719    

DOI:10.1080/00032718408065349

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

A highly selective and sensitive method is described for the determination of para- as well as ortho-isomers of aminophenol. The method involves oxidative coupling of aminophenol with Berthelot hypochlorite-alkaline phenol reagents. The reaction yielded a blue chromophose with p-aminophenol (∑=10,000 at 633 nm) and a dark green chromophore with o-aminophenol (∑=1436 at 845 nm). The reaction mechanisms involved in the chromophore formation are discussed.

ISSN:0003-2719    

DOI:10.1080/00032718408065350

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

This report demonstrates that immobilized trimethylsilane is an appropriate reference standard for MASSCP-13C NMR studies of reagents immobilized on silica gel. An example is presented which shows that the immobilized trimethylsilane exhibits many of the advantages as a reference for these solid samples as does tetramethylsilane for liquid samples. It is further shown that pure solids may interact with an immobilized phase and produce significant spectral changes and thus are not appropriate as reference standards.

ISSN:0003-2719    

DOI:10.1080/00032718408065351

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor