Pulsed Electric Discharges in the Water and Oxide Nanoparticles

Abstract

Summary form only given. The pulsed electric discharges (PED) in water attract more and more attention of researchers. There are at least three reasons: their bactericidal action to pathogenic bacteria and spores of fungi, which are opportunistic to the human beings; destroying ability concerning some of organic compounds, including toxic ones; high productivity of oxide nanoparticles of various metals. The erosion of electrodes at electric discharges in water takes place. As a result of the erosion the metal nanoparticles are in water. Hence some part of the oxide nanoparticles transforms to the ions, the action of the water treated by the PED to the microorganisms must be than more intensively, than the ions are more toxic. The ions of metals on a degree of their toxicity to microorganisms are located as follows; Ag > Cu > Cd. Zn. Pb > Mn, Fe > Mg, Ca. The purpose of this investigation was to determine quantitative relations between parameters of electric pulses, such as their duration, current rise rate, the energy expenditure and specific erosion of electrodes metal, and also characteristics of produced nanoparticles. in particular, function of distribution of nanoparticles sub fractions in the dimension. It was found that at duration of the discharge pulse from 5 to 10 mus there is optimum ratio of those two above parameters, i.e. high specific erosion of electrodes of 5 mg/C at dominant output of nanoparticles with dimension of about 20 nm. which most effectively influence onto bacteria and spores. Besides increase of energy expenditure results in displacement of maxima of distribution of mass of subfractions to greater dimension of nanoparticles and clusters formed by them.