The inactivation of eggs of helminthes under the action of narrowband ultraviolet radiation of excilamps

The inactivation of eggs of Opisthorchis felineus and Diphyllobothrium latum in the water under the action of UV excilamps at 222 and 282 nm in dependence on the surface dose of radiation was studied. It was observed that the water disinfection from eggs of helminthes was more efficient at 222 nm, than at 282 nm. At the surface dose up to 5 mJ/cm2 of UV radiation at 222 nm up to 85 % of Opisthorchis felineus eggs were inactivated. At the comparable surface dose of UV radiation at 222 nm up to 56 % of Diphyllobothrium latum eggs were inactivated

Excilamps and their applications

An innovative class of sources of spontaneous ultraviolet and vacuum ultraviolet radiation, the so-called excilamps, based on the nonequilibrum radiation of exciplex or excimer molecules, is described. The design and some technical characteristics of traditional excilamps excited by a dielectric barrier discharge are presented. The data concerning newly developed types of excilamps excited by runaway-electrons-preionized diffuse discharge both in single and pulse-periodic modes are given as well. Some novel applications of excilamps in photochemistry, the effect of ultraviolet and vacuum ultraviolet radiation on the physiological action of living organisms, photosynthesis, and growth of plants, and the use of excilamps for pre-sowing treatment of seeds are explained in detail

On the question of the source of the apokamp

The object of this work is the apokamp—a new type of plasma jet, which is formed from a bright offshoot emerging at the bending point of a channel of a high-voltage pulse-periodic discharge under conditions where the electrodes have a capacitive decoupling with the ground. The aim of this work is the identification of distinctive properties of the offshoot in comparison with the apokamp. The differences in the spectra of the offshoot and plasma jet (apokamp) were detected experimentally in air under normal conditions. The results of the previous studies, according to which the apokamp is a wave of ionization, were confirmed. The launch of a helium plasma jet from the offshoot of the pulse-periodic discharge in a mode of the apokamp forming was demonstrated experimentally. It was shown that the offshoot of high-voltage pulsed discharge in the mode with the apokamp is a medium that is strongly heated and conducting electric current

The field strength necessary for the formation of blue jets in the middle atmosphere

The formation of blue jets in air at low pressures is simulated using an apokamp discharge. The field strength is measured in the discharge channel. Assuming the applicability of similarity laws to gas discharges, the field strength in a storm cloud during the formation of blue jets is assessed to be from 6 x 1010 to 1.9 x 109 V/m, which is much higher than the values characteristic of the development of cloud-to-ground lightning discharges. A hypothesis is suggested that excess magnitudes of characteristic fields is among features of high-voltage pulsed discharge within a cloud, which results in the formation of blue jets at altitudes of about 12-18 k

Dielectric barrier discharge KrCl - and XeCl-excilamps radiation power control by pressure jump method

The energy dissipation processes in dielectric barrier discharge KrCl- and XeCl-excilamps at various voltage, frequencies and pulse duration are revealed by a pressure jump method. It is offered and tested a way of radiation power calculation in conditions of non-uniform filling of device bulb by discharge plasma. The previous data (Pikulev A.A., Sosnin E.A., 2010-2013) are confirmed. The regularity was formulated: conditions of maximal ultraviolet radiation power corresponds to conditions of maximal heat release in plasma. © (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only

Laboratory demonstration in the air red and blue mini-jets

The properties of apokamps (miniature plasma jets) with length up to 60 cm at low pressures are studied. It is shown that several properties of apokamps resembles that ones for large-scale transient luminous events (sprites, starters and blue jets) observed in the Earth upper atmosphere. The images and spectra of apokamps in these conditions are presented. For the first time red downward directed mini jets in air at pressures of fraction of Torr were obtained

Application of excilamps in agriculture and animal breeding (review)

The paper provides a review of research data on applications of XeCl excilamps in agriculture and animal breeding. The data demonstrate a favorable effect of radiation produced by the excilamps on the fertility of animals (outbred mice and pigs) and on the growth of plants (flaxes, potatoes, carrots, cucumbers, conifers). Excilamp models adapted specially for use in stock-raising and grain storage complexes are now available. The research data obtained in 2012-2015 suggest that XeCl excilamps hold promise for prevention of diseases in indoor-housed pigs and for pre-sowing seed preparation

Fungicidal effect of apokampic discharge plasma jet on wheat seeds infected with Alternaria sp. and Bipolaris sorokiniana Shoemaker

Atmospheric pressure plasma jets generated by apokamp discharge (APPJ AD) in ambient air was investigated for the improvement of growth parameters of spring wheat seeds («Irgina» cultivar) and for inhibition of potentially phytopathogenic fungi on seeds surface. In case of APPJ AD, active forms of oxygen and nitrogen (as well as the radiation of molecules) are formed in the air of atmospheric pressure, which increases their concentration in the streamer head by orders of magnitude, compared to traditional APPJ based on inert gases. Owing to this, we believe to concentrate action of active forms of oxygen and nitrogen in situ, on the biological target. In our case, this can intensify the processes of inactivation of microscopic mold fungi on the surface of seeds. We tested our hypothesis on wheat seeds infected with helminthosporiosis (Bipolaris sorokiniana Shoemaker) with a degree of infection of 50% and early blight (Alternaria sp.), whose infection rate was 10%. In the first case, the seeds were treated by apokamp plasma for 1 and 10 minutes. It provided a significant reduction in the degree of infection of seeds with helminthosporiosis by 1.7 and 2.3 times. In comparison with check variant, the treated seeds maintained high rates of viability and germination energy. In the second case, it was possible to completely inactivate alternariosis pathogens within 3 min of treatment. In addition, it is shown that the action of APPJ AD caused a statistically valid elongation of the roots of wheat seedlings. A hypothesis is proposed to explain the found effects. The potential advantages of APPJ AD in the task of seed surface treatment in comparison with other known atmospheric plasma techniques are discussed

Physiological action of UVB radiation on wheat seeds and sprouts (Triticum aestivum L.)

This work continues the cycle of our research on the physiological effect of UVB radiation on plants. Two research cycles were conducte