摘要:

An anodic voltanmetric study was made of the Ziegler-Natta catalyst in tetrahydrofuran using a rotating platinum electrode. It was shown that these measurements could be used as an indication of the activity of the catalyst. It was also observed that the catalyst and the cocatalyst (diethyl aluminum chloride) formed an electrochemically inactive species. The study was complicated by the presence of an impurity (probably water) In the solvent that reacted with the catalyst and by the formation on the electrode of an inert film.

ISSN:0003-2719    

DOI:10.1080/00032718208069517

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

An indirect polarographic method is described based on the alprade reaction. The formaldehyde produced is determined by its decrease of the hydroxylamine a-c polarographic wave. Sorbitol, ethanediol, mannitol, ethanolamine, serine and threonine are determined in the range 5 – 30 × 10−6M while 2.5 – 10 × 10−6M triethanolamine are determinable.

ISSN:0003-2719    

DOI:10.1080/00032718208069518

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

Trialkylsulfonium- and trialkylselenoniumhydroxides are pyrolytic alkylation reagents that derivatize acidic compounds quantitatively inside the injector of the gas chromatograph. Trimethyl-sulfoniumhydroxide and Triethylsulfoniumhydroxide, the analogues of selenium respectively are stable in cool methanol solution for at least 6 months. The reagents are easy to handle and the byproducts formed are very volatile. Therefore the application of ternary sulfonium- and selenoniumhydroxides is equivalent or even superior to the use of the well known quartary ammoniumhydroxides.

ISSN:0003-2719    

DOI:10.1080/00032718208069519

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

A method is described for the determination of fluoride in geologic materials utilizing a sodium carbonate fusion and an ion chromatographic method of analysis. Excellent agreement is observed with published values for geologic standards ranging from 0.01% to 6% fluoride in the sample. Estimates of precision were based upon the repetitive analysis of United States Geological Survey standard GSP-1. Results indicate a relative standard deviation for the method of 5%. Detection limits were estimated to be 8 ppm fluoride in the sample at the 90% confidence level.

ISSN:0003-2719    

DOI:10.1080/00032718208069520

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

Ion chromatographic separation of tungstate and molybdate is achieved using a 3 × 250 mm standard anion separator column, a 0.006 M sodium carbonate eluent, a standard anion suppressor column, and a flow rate of 90 ml/hr. Elution of peaks for the species tungstate and molybdate occurs at 9 and 12 minutes, respectively, and peak heights are distinguishable from the base line at concentrations of 0.1 mg/L, using a full scale deflection of 10 μmho and a dual-pen recorder. Tungstate and molybdate must be concentrated from 1 L of water by collecting them on a chelating resin after the pH of the water is adjusted to between 1 and 2. Tungstate and molybdate are eluted with concentrated ammonium hydroxide. The amnonia is evaporated, leaving a water solution containing tungstate and molybdate. About 90% of the tungsten and molybdenum is recovered, with a relative standard deviation of about 15% at the 5 μg/L level. Natural concentrations of tungsten or molybdenum as small as 1 μg/L are measured by this technique.

ISSN:0003-2719    

DOI:10.1080/00032718208069521

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

Electrophoretic behaviour of 34 organic acids on calcium sulphate impregnated papers has been studied. The 19 binary separations in aqueous sodium chloride and sodium sulphate solutions and distilled water have been achieved.

ISSN:0003-2719    

DOI:10.1080/00032718208069522

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

The tetraiodoaurate(III) complex forms with the tetrabutylammonium cation the [(C4H9)4N][AuI4] ion-pair which may be extracted with chloroform. The present work studies the variables affecting the extraction efficiency, which in optimal conditions is greater than 99.8%. The absorption spectrum of the organic extract shows two maxima at 292 and 360 nm. Beer's law is followed for gold concentrations of the order of 10−5M. A procedure for the spectrophotometric determination of gold after extracting the [(C4H9)4N][AuI4] ion-pair by chloroform is proposed. Iron(III), Cu(II), Tl(III), Bi(III), Pd(II) and Pt(IV) interfere.

ISSN:0003-2719    

DOI:10.1080/00032718208069523

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

A kinetic fluorimetric method is developed for the determination of microamounts of copper(II) on the basis of its catalytic activity on the hydrolysis of 2-hydroxybenzaldehyde azine. To monitor the reaction, the appearance rate of fluorescence in the hydrolysis reaction product, the 2-hydroxy benzaldehyde hydrazone (λexe= 355 nm., λem= 465 nm.), is measured. The determination of copper at the 100–500 ng/ml level suffers very few interferences. The mechanism of this catalyzed reaction is proposed.

ISSN:0003-2719    

DOI:10.1080/00032718208069524

出版商:Taylor & Francis Group    

年代:1982

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:10.1080/00032718208069516

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor