Influence of the nature of the pasting liquid on the accumulation of nitroanilines at carbon paste electrode during determination by absorptive stripping voltammetry.

ABSTRACT. The accumulation of ortho-, para-nitroanilines, 2,4-dimetyl-6-nitroaniline, and meta-nitrobenzoic acid at carbon paste electrode (CPE) has been studied. For the preparation of CPE different pasting liquids have been used: esters, aromatic hydrocarbons, saturated hydrocarbons, and polymethylsiloxane. Distribution ratios of o- and p-nitroanilines between the pasting liquid and water have been determined. Correlation between peak current constants and distribution ratios has been found. It has been demonstrated that during the determination of analyte on the CPE with aromatic hydrocarbons, the main influence on nitro-compound accumulation is executed by the extraction into the pasting liquids, and on the CPE with saturated hydrocarbons - by the process of depolarizer sorption onto the graphite. The selective determination of nitroanilines in the presence of hindering compounds with adsorptive stripping voltammetry has been carried out.

[The use of ground mollusks in the evaluation of environmental pollution with heavy metals in the city of Ufa]. / Primenenie nazemnykh molluskov dlia otsenki zagriazneniia territorii g. Ufy tiazhelymi metallami.

The authors analyzed soil and cochleae of bush snails in Ufa for heavy metals (Zn, Cu, Pb, Cd) content. Zn and Cu content of the soil exceeds the background levels and approaches the MACs. Pb and Cd content corresponds to their usual content of soil. The coefficients of Zn, Cu, Pb and Cd pass from soil to cochleae of bush snails increase in the row Pb < Zn < Cu < Cd and never outnumber 1.

[Concentration of imidazolines in the air]. / Kontsentrirovanie imidazolinov iz vozdukha.

Using chamber for adjustable mode and dosing apparatus, the authors studied conditions of imidazolines' condensation from the air into 60% ethanol, to paper filters of "white tape" type, to analytic filters of AFA-HP type, into a shell with ultrathin layer of sorbent (2.7% sulfuric acid in 20% solution of glycerine in water). The best results were provided by experiments using the paper filter of "white tape" type and absorbing objects filled with 60% ethanol and containing spongy plate. Rate of the air pumping equalled 2-3 l/min and 0.5 l/min respectively.