摘要:

Evidence is obtained to show that the ion-dipole bond between an ion and the water molecule adducts surrounding it is stronger than the bond between the ion and the organic phase molecules. The water adducts cannot be displaced and the system remains hydrophilic and resists extraction.

ISSN:0003-2719    

DOI:10.1080/00032718408065353

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

The electrochemical behaviour of the R-nitroso salt in 0.5MHAc/NaAc at pH 4.7 is studied by cyclic voltammetry. The compound shows a very sharp reduction peak at -0.37 V vs SCE giving the corresponding amine derivative. The height of the peak is shown to be inversely proportional to the iron (II) concentration of the solution. A linear calibration plot is obtained between 0 and 56 ppm of iron (II) using, initially, 4.0mMsolution of the salt. A simple and fast procedure was developed for the analysis of standard samples of ferrous iron.

ISSN:0003-2719    

DOI:10.1080/00032718408065354

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

A method for the assay of sulfur in organic liquids is presented. The method utilizes an oxidative combustion process coupled with a piezoelectric crystal detector. The sulfur dioxide evolved upon combustion of the organic liquid is bubbled through a mercurous nitrate solution. The mercury vapor produced is detected by a piezoelectric crystal due to the formation of a mercury amalgam.

ISSN:0003-2719    

DOI:10.1080/00032718408065355

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

The complexes formed by the Na+, K+, Rb+, Ca2+, UO2+2, and Ag+cations with the macrocyclic polyethers 18-crown-6, benzo-15-crown-5, and dicyclohexy1-18-crown-6 are investigated. The stability constants of these complexes have been determined potentiometrically in (90% vol.) ethanol-water solutions at 25[ddot]C and an ionic strength μ= 0.1 (achieved with tetrabuty lammonium perchlorate). The stablity of the investigated complexes was interpreted in terms of “caging” the metal cation into the cavity of the macrocyclic ligand, an effect which depends on the ratio of the diameter of the complexed cation over the diameter of the cavity of the complexing ligand.

ISSN:0003-2719    

DOI:10.1080/00032718408065356

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

The interferences encountered in trace metal analysis of plant media by ET-AAS are described. The atomization of Cd, Cr and Ni are weakly perturbed by the plant matrix elements and no corrections have been investigated. For Pb, T1 and Sb a drastic slope reduction of the working curve is observed, which drastically reduces sensitivity. These perturbations are minimized by the L'vov platform technology, the efficiency of which has been tested with four commercially available ET-AAS systems. Matrix modification by ascorbic acid may be also efficient.

ISSN:0003-2719    

DOI:10.1080/00032718408065357

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

A spectromeric study of the reaction of the Zr(IV) ions with Mandelazo I was carried out. Absorption spectra revealed that the maximum absorption of the zirconium compound appears at a wavelength (316 nm) different from the maxima of the reagent (253 and 390 nm). Beer-Lambert law is followed for zirconium concentrations of the order of 8.8x 10−5M (i.e. 8 μg Zr (IV)/mL). Possible interferences of ions such as Be(II), Cu(II), Zn(II), Al(III), Th(IV), U(VI), Mn(II), Fe(III), Co(II) and Ni(II) were investigated in connection with some masking agents such as SO42-and C2O42-. Also, the solid state Zr(IV)-Mandelazo I compound was prepared and characterized by nitrogen and thermogravimetric analyses.

ISSN:0003-2719    

DOI:10.1080/00032718408065358

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Two vapor-liquid equilibrators to saturate water with organic solvent without forming two liquid phases were developed, thus permitting a more accurate determination of organic adducts to metal chelates. An equation was developed to show that vapor pressure measurements could be used as an alternative method for determining the number of organic adducts on a metal chelate in the aqueous phase.

ISSN:0003-2719    

DOI:10.1080/00032718408065359

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

A solid reagent of Purpald®-acetone aminal on sodium or potassium bicarbonate responds to formaldehyde in the sub-ppm concentration range. A purple color (λ=560 nm) is developed proportional to concentration of formaldehyde and time of exposure after wetting with a 90% acetone-10% water solution. The reagent should be of value as a semi-quantitative warning device for the presence of formaldehyde. A device is described which generates formaldehyde in air in the sub-ppm concentration range at room temperature with desired relative humidity. This generator could be used in the same manner to generate low concentrations of other substances of low volatility.

ISSN:0003-2719    

DOI:10.1080/00032718408065360

出版商:Taylor & Francis Group    

年代:1984

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:10.1080/00032718408065352

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor