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The scientific conference "Technogenic Systems and Environmental Risk" is held annually from 2004 to 2017 at Obninsk Institute for Nuclear Power Engineering, NRNU MEPhI. The main participants of the conference are students, graduate students and young scientists, including representatives of research institutes, universities, scientific and industrial associations and enterprizes. Since 2017, the meeting has officially been recognized as an international conference.

The II International (XV Regional) Scientific Conference "Technogenic Systems and Environmental Risk" 2018 (TSER-2018) was held in Obninsk, Kaluga Region, Russian Federation on April 19-20 2018. It was organized by National Research Nuclear University "MEPhI" (NRNU MEPhI)

The conference addresses current scientific problems related to the study of man-made factors in the human environment, the evaluation of the effect of these factors on humans and natural systems, ensuring the ecological safety of the biosphere. The meeting contributes to raising the level of knowledge of young scientists and teachers, sharing experience in conducting research and teaching activities, establishing links between organizations, regions and countries.

List of Local Organizing Committee, International Program Committee and Keynote Speakers are available in this pdf.

All papers published in this volume of IOP Conference Series: Materials Science and Engineering have been peer reviewed through processes administered by the proceedings Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

Now the Republic of Belarus has a modern system of radiation monitoring of the environment, which is based on innovative technologies, including information technologies. The Republic of Belarus has good practices in organizing radiation monitoring of the environment after the accident at the Chernobyl NPP. Between 1986 and 2017, over 630,000 soil samples were measured for radionuclide contamination, including cesium-137. With the use of GIS technologies maps of radioactive contamination of the territory of Belarus with cesium-137, strontium-90, isotopes of plutonium and americium-241 have been created. New methodical approaches to the formation of a radiation monitoring system were developed in case of new threats to radiation safety, for example, the construction of nuclear power plants. Based on the experience of studying the behavior of radionuclides, an integrated biospheric approach to the organization of radiation monitoring of the environment is developed.

Probable locations of the sources of ruthenium-106 in the atmosphere in September-October 2017 have been considered. Taking into account the monoisotopic nature of the increase in ruthenium-106 concentration in the ground level air and atmospheric precipitation, the most probable version is substantiated, which suggests that ruthenium-106 came from a ground source located in the Southern or the Middle Urals. In order to locate the possible point of Ru-106 emission into the atmosphere, calculations of the time-inversed travel of air masses at the heights of 500-1500 m from the Ru-106 concentration measurement locations at European points during the relevant observation period were used. To confirm the correctness of the source location, calculations were performed that involved simulating regional transport and propagation of radioactivity in the near zone in case of a hypothetical emission of ruthenium-106 from a conventional source in the Southern Urals, in order to compare the simulation results with the available daily ruthenium-106 drop-out measurement data.

The experimental stand «FKBN» (physical fast-neutron boiler) is a critical assembly in which the vertical lift mechanism is used. With the help of such stands, in the second half of the 20th century, experiments were conducted on the effect of various materials in various designs on the kinetic characteristics of a system with fissile material. Mostly, such works were conducted in Los Alamos National Laboratory (USA), Oak Ridge Laboratory (USA), VNIIEF (Russia), VNIITF (Russia). On such installations, there were often accidents with the emergence of a self-sustaining chain reaction. One of these occurred on April 5, 1968 in VNIITF in Chelyabinsk-70 (now Snezhinsk). In this paper, the critical state of the stand is calculated for different distances of the reflector from the core under the conditions of the presence and absence of solid polyethylene inside the core. The configurations in which K_eff=1,000 and K_eff=1,000+β_eff are of interest are of interest. As a tool, the CSAS6 sequence of the SCALE-6.2.1 software package was used.

In this article, the main problems and man-caused risks are considered in the event of a heat exchange crisis in nuclear power plants (NPP). A thermophysical booth simulating the operation of a nuclear reactor was developed. The data of acoustic diagnostics of the boiling of the coolant on the basis of the work of the laboratory stand were collected. Methods for processing and analyzing data collected from acoustic sensors have been developed. The recording and processing of signals was carried out using the application package and MATLAB programming language. The article describes the application of correlation and spectral analysis for data processing and analysis. The authors also use regression analysis to find the dependence of wall temperature on the frequency of acoustic oscillations. Forecasting the values of the wall temperature from the frequency of sound vibrations makes it possible in the future to find diagnostic features and build a mathematical model for detecting boiling and heat transfer crisis in nuclear power plants.

Nowadays the total electricity generated in nuclear power plants in Russian Federation is approximately 18% of all power generation. There are 36 reactors in operation in Russia, 19 of which are reactor plants WWER-1000. A planned operation lifetime of these plants is 30 years and most of them have served for this period. To extend reactor working lifetime it is necessary to carry out the calculation for possibility justification of continued operation of reactor equipment and pipelines. The paper presents the static strength calculation of DN 350 branch pipe cutting-in in the main circulation pipeline of reactor plant WWER-1000. According to calculation results a following conclusion is made: if the static strength of DN 350 branch pipe cutting-in meets the requirements of technical standard, the continued operation of this pipeline section will be possible.

When calculating the reliability indicator of any device, under specified operating condition, usually reference data on the characteristics of the reliability of the elements. Data on the reliability of the groups of electrical-radiation equipment (ERE), used in the design, manufacture and operation of equipment, instruments, devices include information on the mathematical models to calculate (predict) values for the operational intensity of product groups, including information on the storage conditions and information on the reliability groups ERE and the coefficients of the models. This paper considers methods for the refinement of correction factors to estimate the failure rate of ERE under specified conditions. The results of the work allow us to clarify the existing coefficients for the prevention and reduction of the failure rate of ERE, as well as to prevent failures of elements and systems due to personnel errors.

Boron is widely used in nuclear power as a neutron absorber material, thereby creating the possibility of controlling a nuclear reactor by changing the neutron multiplication factor. Natural boron contains about 20% ¹⁰B and 80% ¹¹B with absorption sections respectively 3840 barn and 0.05 barn. The paper deals with changes in neutron-physical parameters of the reactor core of VVER type when the isotope content of ¹⁰B in boron carbide of absorber rods (AR) of the control and protection system (CPS) and in boric acid solution in the coolant of the VVER reactor is varied, and also analyzes the practicality of increasing the enrichment of ¹⁰B isotope in the control rods (CR). The model of VVER-1200 fuel assembly (FA) was used for calculations. In the course of work were modelled and the calculations of the three models of the coolant with different boric acid concentrations, as well as two models of AS with different enrichment in the isotope ¹⁰B.

During operation of the reactor, along its active zone, the energy release is unevenly distributed, consequently also the temperature. These operational parameters introduce an error in the measurement of the system. Of practical interest is the study of the temperature stability of ultrasound sensors, as well as the effect of vibration on the oscillations of the ultrasonic signal. The system solves the problem of controlling the curvature and the diameter of the cells of the graphite masonry of the EGP-6 reactors in two mutually perpendicular planes during the routine preventive and overhaul repairs. Diameter control is carried out by means of 4 sensors of displacement of the resistor type fixed on the sensor probe block. Each of the sensors is mechanically connected to the roller, which is in direct contact with the channel wall. Diameter measurement uses data from sensors connected to two opposite rollers. Curvature control is performed using an ultrasonic inclinometer filled with liquid, which is located in the tail part of the probe. The inclinometer is designed for measuring angles of inclination in 2 mutually perpendicular planes. The data from the inclinometer is transmitted via the interface to an analog-to-digital converter, which is located in the measuring unit and is designed to convert the interface to USB.

Method Monte Carlo is applied to assess the radiological impacts to the environment. As such cases, determining the dose rates due to external radiation source is considered, that is induced by radioactive inert gases when they are released from a nuclear power plant; also to estimate the volumetric concentrations of the released radioactive inert gases, and other characteristics associated with the use of gamma detectors of the automated radiation monitoring systems of the environment and unmanned aircraft radiometric system. In order to assure the reliability and the accuracy of the calculations by Monte Carlo method for the dose rates estimations, the results are compared with the results that obtained by the integral method, which showed satisfactory agreement.

In this work there is a detailed methodology for the assessment of the radiological ecological risk at the ecosystem level based on critical loads. Risk assessment consists of the following stages: hazard identification, identification of reference species and indicators, determination and analysis of critical loads on the basis of the dose-effect relationship, environmental risk assessment and analysis of risk functions. The experimental site is the territory, which has been exposed to radioactive contamination as a result of depressurization of the storage capacity of radioactive waste. On the basis of long-term (2010 – 2015) monitoring works, the input parameters for risk assessment were determined: the recipient of the impact is the terrestrial ecosystem; in the study of chemical and radioactive contamination of the territory, an environmental hazard factor was identified – Sr-90; the reference species - the mollusk Fruticola fruticum and reference indicators – the coefficient of accumulation of the Sr-90 of shells from the nettle and catalase enzymatic activity of soils. It was determined the acceptability of radiation risk for the terrestrial ecosystem on the basis of critical loads on the catalase activity of soils and unacceptability when accounting the coefficient of accumulation of Sr-90.

In the lack of experimental data and due to the rapid development of numerical modelling and computer hardware, computational fluid dynamics (CFD) is widely used to study wind field and contaminant transport around buildings. The ability to predict quantitative values for these processes is not so clear. CFD simulations work under neutral atmospheric conditions and are validated by the Gauss model. The Gaussian model is a mathematical distribution of the concentration of contaminants from NPP ventilation pipes. It is the most recommended model by the IAEA and most widely used because 1) it gives results consistent with experimental data, 2) it is quite easy to use, and 3) it is consistent with the aleatory nature of turbulence. Reynolds-averaged Navier-Stokes equations is the most widely used method in turbulent flow modeling and simulation. In this paper, the prediction of flow accuracy and propagation around buildings with a stack was examined using k-ε model. The numerical results were compared to Gauss model results. Contaminant dispersion was well predicted with k-ε model. It was also confirmed that the concentrations predicted by the CFD models were more diffused than those of the Gauss model and that the results depend on the position of the obstacles.

Radiation dose rate for a terrestrial mollusk Fruticicola fruticum was assessed under chronic Sr-90 irradiation in field conditions by three methods. The study-site is the territory nearby the radioactive waste storage facility in the Kaluga region. Due to a loss of integrity in one of the storage capacities, there was a leakage of radionuclides in 1998. Specific activities of Sr-90 in soil, plant and shells of terrestrial mollusk used as the input parameters for calculating the radiation dose rate are: 20±3 – 5203±785 Bq/kg; 22.3±13.4 – 10596 ± 195 Bq/kg, 76±11 – 17640±2646 Bq/kg, respectively. As a result of the calculations, the following radiation dose rates were obtained: from 10±2 to 1634±245 mGy/year with the J. Levinger and L.D. Marinelli formula, from 0.012±0.001 to 2.1±0.2 mGy/year with the Erica Assessment Tool, from 0.32±0.07 to 76±9 mGy/year by the Monte Carlo method. The Monte Carlo method gives the most adequate estimates, because the application of this method allows taking into account the maximum possible scenarios of mollusk irradiation, the maximum number of input parameters, including the weight and geometry of the organism, the dosimetric and physical features of the source of irradiation.

The document discusses the development of a system for responding to a nuclear emergency that could affect the agricultural sector. The analysis of some decision support systems showed that while the development of such a system there should be taken into account the advantages of the existing software tools allowing to derive recommendations for countermeasures and remediation of agricultural territories affected by the radiation accident. The consequences of major nuclear disasters have shown that the new system should consider the international experience on mitigation of the impact to agriculture, as well as consider potential nuclear emergencies, which can affect the territories located in the vicinity of nuclear facilities.

The aspect of ensuring NPP safety has always attracted scrupulous attention. Experience in operating power plants with different reactor types shows that radiation situation in the NPP area, environmental contamination depend very much on the integrity of the fuel cladding – one of the most important protective barriers.

In practice, some fuel pins in the core can have certain cladding defects occurring during the normal plant operation, with a BN-type reactor used. Np, Pu, Am, Cm transuranic elements may take special part in contaminating the primary circuit with actinides. Presence of actinides in the process media of the reactor facility may have radiation effect not only on the NPP staff but also on the population living outside the buffer area.

There is little information on the problem in scientific publications. Computer codes are mainly oriented to the calculation of the effective doses the population take as a result of release of radionuclides into the air during the first year of NPP operation. Increasing the duration of NPP operation results in significantly complicated calculations. This paper presents a simplified method of calculating the main components of the annual effective dose the population receive due to release of actinides into the air over «n» partial refuelings after reactor startup.

Short-term hydroponic experiment was conducted to evaluate intensity of the ¹³⁷Cs transfer from a solution with extremely high activity of the radionuclide into onion, considering different plant's compartments (green leaves, bulbs, roots). It has been revealed that the root uptake of ¹³⁷Cs was significantly discriminated, and not exceeded 0.01% of the total amount of radionuclide contained in the solution. At the same time, biometric indices of the plants – shoot height, roots elongation, phytomass inventory and structure – under conditions of ¹³⁷Cs stress exposure were not significantly changed in comparison with the control. The main accumulation of ¹³⁷Cs, which incorporated into onion, occurred in roots, especially in root tips, which are most actively involved in the processes of mass exchange between the plant and the external environment. The translocation of ¹³⁷Cs into the shoot part, including the onion bulb and green leaves, was significantly suppressed, which allows considering the root system of onion as a biological barrier providing the rhizofiltration of the toxicant.

Here, we present the comparative studies of DNA damage induced by X-ray irradiation in vitro in mouse, frog and human blood cells and assessed by the "comet test" (alkaline version). We showed that, in contrast to mouse and human cells, DNA repair processes in frog blood cells are not completed by 60 minutes of the post-radiation period. The results suggest that frogs can be used as indicators of environmental radiation pollution. In this regard, additional experiments are needed to assess the different types of external and internal exposure of animals.

The article considers the research of the plant pigments content in the upper layer of the bottom sediments in the rivers (the Serovka, the Yagorba, the Sheksna), which are affected by communal and industrial wastewater in Cherepovets. The average content of pigments in the bottom sediments of the Serovka and the Yagorba rivers was higher than in the Sheksna river during the observation period (July 2015 – December 2016). According to the indices E480 / E665, E480 / (1.7E665k) and the ratio of chlorophyll to pheophytin, the pigmentary fund of benthic algocenoses is mainly in a degraded state. In terms of chlorophyll and pheopigments (calculated on dry soil) amount, the bottom sediments of the Serovka river are characterized by the mesotrophic category values, while the ones of the Yagorba and the Sheksna rivers – by oligotrophic values.

We have shown that γ-irradiation at dose of 10 Gy and low-intensity electromagnetic fields (EMF, 900 MHz, 100 μW/cm², 180 min) significantly compromised cell proliferation of planarian S. mediterranea regenerating after decapitation. Using flow cytometry we have shown that 24 hours after exposure to γ-rays and EMF the index of proliferation established as the total amount of cells at S and G2/M phases was 2.8 and 1.8 lower than that in controls respectively. Our data therefore provide the first experimental evidence for the effects of medium-dose γ-irradiation on regeneration in planaria which is attributed to radiation-induced compromised proliferation activity.

The separate and combined impacts of aluminium and selenium ions on different barley cultivars and onion (Allium cepa L.) seedling as well as ions copper, zinc and nickel on onion have been studied. The experiments have been performed in several series with different solutions of ions: aluminium have been used in concentration of 0.5 mg/l (Russian MPC for cultural-domestic water), ions of Fe, Mn, Se, Ag and their combinations with ions of Al have been used in concentrations corresponding to the values of Rus MPC for cultural-domestic water. At the same condition were chosen the concentrations of copper, zinc and nickel. The phytotoxic and genotoxic effects (as mitotic index – MI and aberrant cell frequency – ACF) were estimated. It was showed that aluminium ions promote higher phytotoxic and genotoxic effects, but in combined with another ions the negative effects on barley and Allium cepa reduced. This confirms that the universal mechanism the interaction between two metals (aluminium and other) and their detoxification effect in plant. The essential metals Cu and Zn and the toxic metal nickel provide a strong cytogenetic effect which results to ACF increasing and MI suppression. We assume that the mechanisms of detoxication should be initiated by metals themselves.

Regulatory peptides are one of the main signaling molecules that provide intercellular interactions in biological systems. Thus, regulatory peptides are known as morphogens - biologically active substances involved in the regulation of the morphogenesis of animals and plants. Until now, the interaction of plant and animal peptides and, in particular, the 'cross' effect of plant peptides on the morphogenesis of animals and vice versa has not been sufficiently investigated.

The present work is devoted to the study of the effect of growth regulator peptide (CLV 3) of Arabidopsis on the morphogenesis of animals - freshwater flatworms – planaria. This peptide is an effective regulator of growth and differentiation of plant roots in low and ultra-low concentrations.

Various biophysical methods have shown that this plant peptide at a concentration of 10⁻⁹M is also an effective morphogen of animals. At the same time, the specificity of the action of peptides on 'unrelated' biological targets has been found. The peptide CLV 3 stimulates on the morphogenesis of plant roots in concentrations up to 10⁻¹²M, while for planarian regeneration it acts only at concentrations up to 10⁻⁹M, at which it does not show a noticeable effect on root plant growth. When this peptide was applied to the of stem human stem cells Th culture, there was no effect observed.

The results of the study confirm the thesis that there is a general biological level and peptide regulation mechanisms that are similar for animals and plants, and also reveal the nature of the specifics of the 'direct' and 'cross' action of this mechanism.

The effect of molybdenum on the germination of seeds of agricultural plants common vetch, white mustard and oats in the presence of Rhodoccocus-biosurfactants was studied. Molybdenum in concentrations from 10 MPC and above had a pronounced inhibitory effect on the germination of seeds. It has been found that pretreatment of seeds and their germination in the presence of biosurfactants contributed to a significant (up to 4.5 times) increase in germination, germinative energy and viability of Avena sativa L., Sinapis alba L. and Vicia sativa L.

An analytical solution to control the active ingredient in the air, a pesticide of the chemical class of triazolinthione – prothioconazole, which is a systemic fungicide of a new generation that has a protective, eradicating and curative effect, the article presents. The method is based on HPLC with an ultraviolet detector (detection wavelength 213 nm), involves the air samples on high-density paper filter with an aspiration rate of 5 l/min. Extraction of prothioconazole from the filters is performed with acetonitrile. To concentrate the extract from the filters, solid-phase extraction using octadecyl silane-based cartridges is used. Was noted that the concentration cannot be performed directly without diluting the aliquot of the extract with water in a ratio of 1:9. Due to the special properties of this active ingredient, its propensity for degradation, the amino acid cysteine is used to stabilize the aqueous solutions obtained. The linearity of the calibration characteristic was confirmed in the concentration range 0.05-0.5 μg/ml (correlation coefficient more than 0.999). The lower limit of the quantitation of prothioconazole in the air environment is 0.0025 mg/m3 when aspirating 80 L of air, which is 8 times lower than the established value of approximate safe level of influence prothioconazole in the air of urbanized places (0.02 mg/m³). The total measurement error doesn't exceed 16%.

The antioxidant and genoprotective properties of the antidiabetic drug metformin have been investigated. The research was performed both in vitro and in vivo under X-ray irradiation. It was shown that metformin reduced the formation of hydroxyl radicals and hydrogen peroxide in aqueous solutions irradiated with X-rays. The particular features of its influence on the formation of H₂O₂ were revealed. It has been established that metformin reduced the formation of 8-oxoguanine, a key biomarker of oxidative damage to DNA, in vitro. The effect of metformin on the frequency of micronucleus formation in polychromatic erythrocytes of bone marrow of irradiated mice was investigated. Its genoprotective and radiomimitatory properties at different concentrations and times of application are shown.

Electron beam impact on the radiation resistance of organochlorine hydrocarbon is considered for two forms of pesticide – a pure chemical compound and a component of active substance of a pesticide product to be disposed of. State standard reference samples (SRS) of hexachlorocyclohexane (HCH) – lindane and hexachlorane dust – are used. The fullness of decomposition are determined for lindane and organochlorine compounds as part of the active substance, depending on the aggregate state of the preparation and the absorbed dose of electronic radiation. In all samples, a reduction in the radiation resistance of HCH and its isomers is detected within the range of the radiation dose (D) from 10 to 200 kGy. The maximum decomposition is observed in the suspension of the preparation. The dependence of a degree of decomposition on the amount of radiation dose is not linear.

Aqueous solutions of Beetroot Red fade fairly quickly, when kept in daylight, due to betanin hydrolysis. Aqueous solution produced out of Beta vulgaris chips is an unstable disperse solution. Protein coagulation results in turbidity and residuum in the solution under storage conditions. Proteins and the colorant form hydrogen bonds. Under coagulation of these bonds, the colorant is released and colorant hydrolysis is initiated. Hindered protein settling leads to the colorant precipitate together with the protein. In order to stabilize the colorant solution, we have used colloid protection that helped the solution retain the color continuously. Guar gum was used as a high-molecular compound to stabilize the color of the solution continuously.

In recent years, more and more attention has been paid to nanoparticles (NPs) as target drug delivery systems. Silicon-based nanoparticles are one of the most biocompatible nanomaterials that have become widespread. In this research, we studied the possibility of gallium-68 sorption on silicon (Si-SiO_x) and silicon dioxide (SiO₂) nanoparticles without their surface modification. Conditions allowing to obtain ⁶⁸Ga-NPs with radiochemical yield ≥ 90% were found. ⁶⁸Ga-SiO₂ showed much higher stability over ⁶⁸Ga-Si-SiO_x in both in vitro and in vivo experiments.

The non-steroidal anti-inflammatory drug diclofenac (2-[2-(2,6-dichloroanilino)phenyl] acetic acid) is one of the most frequently detected pharmaceuticals in the environment. The ability of actinobacteria of the genus Rhodococcus to biodegrade diclofenac (170 μΜ) as the sodium salt has been revealed. Cells of R. ruber IEGM 231 pregrown with diclofenac (1.7 μΜ) removed diclofenac (about 50% degradation) within 56 days in the presence of glucose. Diclofenac induced changes in the morphometric characteristics of rhodococci. The products of diclofenac biodegradation did not have pronounced phytotoxicity.

Radiation accidents at nuclear installations are usually accompanied by releases of volatile and biologically dangerous iodine radionuclides into the environment, which can lead to contamination of large areas and cause irradiation of the thyroid gland (TG) in the population and mammals. The reference representatives of biota in radioactive contamination of agricultural ecological systems can be agricultural animals. The basis for the selection of farm animals as reference species is the availability of data of constant veterinary control of animal health indicators and characteristics of their changes due to radiation exposure. To date, the regularities of radiation pathology of the thyroid gland in farm animals with the arrival of radioactive isotopes of iodine have been studied. At the same time, the computational base and software for quantitative analysis of dynamics of formation of radiobiological effects are not sufficiently developed. Using numerical models, namely: a) a compartment model of the ¹³¹I metabolism and (b) precise radiation transport model for the thyroid gland the radiobiological characteristics for calves' thyroid irradiation is derived for the experimental conditions. As a result of experimental and calculated data comparison, critical dose resulting in rapid (within a day) radiation destruction of the parenchymal thyroid tissue was estimated.

The purpose of this work is to reveal the activation of natural defenses reserve in mice after treatment with different physico-chemical agents in vivo using previously developed technology of adaptive response induction. Physical agents were represented by X-rays, carbon ions, infrared light, He-Ne laser light, famine and chemical agents – by immunomodulator CaCl₂ and anti-inflammatory drug ibuprofen. The following tasks were set: assessment of cytogenetic damage using a micronucleus test, the weight index of lymphoid organs (thymus and spleen) and the level of ROS production in whole blood through the method of luminol-dependent zymosan-induced chemiluminescence. SHK mice were irradiated according to the scheme of adaptive response. Analysis of data on the number of cytogenetic damage in bone marrow showed that pretreatment of the animals with all investigated agents and subsequent exposure to X-rays or carbon ions at a dose of 1.5 Gy has led to a decrease in radiosensitivity compared to the nontreated animals. Similar results were observed when analyzing weight index of lymphoid organs. Determination of level of ROS production has shown that the activation index calculated according to the relation of induced to spontaneous light area, was significantly higher in all groups of mice, indicating activation of the natural defenses reserve as compared to the group exposed only at a dose of 1.5 Gy. The obtained results confirm the assumption of revealing activation of the natural defense of the organism with the help of the adaptive response induction technology.

The paper considers the results on the efficiency of application of ionising radiation for grain disinfestation. It is shown that gamma-irradiation of confused flour beetle (imago stage) inhabiting on the barley grain, in a dose range 0.7–1.0 kGy caused the 100% mortality of the pest in 15 days after irradiation at a dose rate 0.5 kGy/h. The similar occurred at doses 0.15–0.6 kGy and dose rate 1.8 kGy, and at the dose rate 0.1 kGy/h the total pest mortality occurred in 30 days after the irradiation. The use of the bremsstrahlung and electron radiation for treatment of barley contaminated with confused flour beetle allowed to establish that the mortality of 100% of the insect-pests occurs in 15 days after irradiation at all studied doses and dose rates in case of both radiation types, with exception of the dose 0.25 kGy (bremsstrahlung radiation), when the organisms perish in 30 days after irradiation. The use of gamma-irradiation for radiation disinfestation of grain affects its quality, which depends both on the radiation dose and the dose rate. It was found that the gamma-irradiation caused the increase of the ash content in the grain by 4–6% at doses 0.2–0.6 kGy (dose rate 0.1 kGy/h) and by 9–19.9% at doses 0.75–1.0 kGy (dose rate 1.8 kGy/h). The application of the bremsstrahlung and electron radiation within the investigated dose range had no significant effect on the quality of barley grain of Nur variety. The results obtained on the assessment of the sensitivity of insect-pests (Tribolium confusum Duv.) to the effects of different ionising radiation types indicate the prospects of the use of ionising radiation for grain disinfestation.

Electromagnetic field levels at workplaces may exceed permissible limit values. In this case the individual protective means use obligatory. There are presented the date of typical samples of conductive suits (under work in power frequency electric field) testing by simulation and in experiment. Individual protective means screening factors were changed from 42.26 to 52.43 dB. The averaged electric field level inside of conductive suit was 220 mV/m in case of simulation. The induced electric fields in human body tissues with conductive suit were 0.003-0.150 V/m. The results show that conductive suit use allows reducing the induced electric filed levels and ensures worker safety.

The negative effect of acute barley irradiation depends both on the spectrum of UV radiation and on the stage of plant development. UV-B radiation, having a higher photon energy, has the greater negative effect compared to UV-A radiation at the same dose of irradiation. During the vegetation, barley is the most sensitive to the influence of ultraviolet at the II-V stages of organogenesis (in the transition from the vegetative to the generative stage of development). The adverse effect of UV-B radiation on the grain yield shows in the substantial reduction of flowers in the ear during their laying and probably in the pollen sterility.