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This report describes the direct voltammetric detection of peroxynitrite (PN, ONOO-), an important analyte in many physiol. biochem. pathways, at a mercury film electrode (MFE) at alk. pH. The voltammetric response of PN is obsd. as a cathodic inverted peak when the potential is swept in the oxidative direction at ~-0.1 V vs. a Ag/AgCl/1 M KCl ref. electrode. An mechanism is proposed to explain this behavior involving the initial formation of a thin film of Hg(I) oxide on the electrode which is then oxidized by PN to form HgO in a chem. step. The HgO is then reduced back to Hg(0) at the electrode potential of interest resulting in a net cathodic current. The parameters affecting the voltammetry of PN at a MFE, including the concn. of PN (10-5-10-4 M), the effect of varying scan rate (5-100 mV s-1) and pH are investigated and the kinetics of PN decay in alk. solns. ranging from pH 9-13 are explored electrochem. [on SciFinder(R)

Abstract.Modern society, which sets problems of translating culture in a new way, determines new criteria for the educational paradigm. Globalization tendencies in modern educational environment induce the problem of necessity to integrate educational and scientific resources into Russian education. The aim of this article is to demonstrate a significant part of scientific research as a consistent factor in formation of the competence-based model of a professional. It is shown that students' research work beyond the process of education becomes a unique sort of teaching activity, which has a number of essential differences from the main traditional teaching techniques for compulsory courses. The results of students' research work in the ecological situation of Siberian region are presented. The competencies acquired by students during this work are revealed. It is noticed that integrating the theme of students' research work with compulsory courses is one of the most important teaching peculiarities in formation of personal attributes of a future highly-qualified professional, which form the basis of professional mobility and competitiveness. It is summarized that an interdisciplinary character of research work in the modern educational paradigm is aimed at solving innovative tasks of integrating educational, scientific and practice-oriented constituents in the context of the competency building approach.

Power expenditure for water purification to remove arsenic(V) was determined. The processes and kinetics of purification in an electric-discharge reactor with a metallic (aluminum or iron) charge were investigated. The purification mechanisms based on the adsorption of arsenic(V) on a fresh surface of hydroxides formed through dispersion and subsequent oxidation of a charged metal were suggested. Rate equations corresponding to the experimental data and to these mechanisms were given.One of problems accompanying many commercial processes, especially those in the metallurgical industry, is effective removal of arsenic and other toxic elements from wastewater. Methods for arsenic removal from wastewater can be combined in two groups: those with and without reagents. The second group includes galvanocoagulation, electrocoagulation, and electropulse water purification.

We have obtained magnetite nanoparticles (MNP) by using chemical coprecipitation of Fe2+ and Fe3+ in water solution. The size of these particles was less than 9 nm, and they possessed corresponding physical and chemical properties. Citric acid was used to stabilize magnetite particles suspension. The acid was affixed to the surface of the particles by adding it in fresh MNP solution during synthesis. Affixing carboxyl groups on the surface of MNP not only does improve particles' dispersion in solvent, but also allows adding further modifications to their surface. The properties of the particles' microstructure and morphology were determined with X-Ray diffraction (XRD) and transmission electron microscopy (TEM), whereas their magnetic properties were determined by means of automated pulse magnetic field analysis equipment. Magnetic measurements have shown that saturation magnetization was 94 emu/g with nanoparticles being at room temperature. We have also researched possible application of these particles as drug carriers by determining doxorubicin sorption capacity on the surface of MNPs. These MNPs have proven to have perspective ability to be a magnetic field-controlled carrier for cancer-treating drugs. The obtained particles can also potentially be used as a contrast medium for MRI.