INSTITUTE OF RADIATION PROBLEMS
AZERBAIJAN NATIONAL ACADEMY OF SCIENCES
DEPARTMENT OF PHYSICAL, MATHEMATICAL AND TECHNICAL SCIENCES
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Main scientific achievements

Main scientific achievements made over the last five years:

I ISSUE: CONVERSION PROCESSES OF NUCLEAR ENERGY AND ITS APPLICATION IN SOLUTION OF ECOLOGICAL PROBLEMS
1. In the result of radiation-oxidation process (T=300K, D=432kQr, oxidizing-H2O2) it is formed an oxide layer with nano thickness, resistant to aggressive environment on the surface of stainless steel containing phosphorus in various amount. It has been determined that with increase of the amount of phosphorus in the composition of stainless steel, the influence of radiational oxidized surface on radiolytic decomposition process of water occurring in the environment of contact decreases and so it indicates the increase of radiation resistance of surface.
2. For the purpose of revealing the usage possibilities of decomposition energy of radioactive radium isotope in obtaining hydrogen from water with radiation-catalytic method, it has been synthesized Ra-SiO3, containing various amount of radium and studied radiation-catalytic activity in radiolytic decomposition process of water at T=300÷673K range. It has been defined that catalytic activity of silicate increases in radiation-catalytic decomposition of water with increase of radium amount in it and it shows that radioactive decomposition energy of radium is used as an additional energy source in radiation-catalytic process.
3. Obtain of molecular hydrogen and oxidation of surface occurs in contact of monocrystalline silicium with water in the result of radiation-heterogeneous processes. The process speed and dependence regularities of hydrogen energetic yield on temperature (T=300÷673), pressure of water vapour in environment (P=0÷5 atm.) and thickness of monocrystalline silicium have been revealed. It has been developed the theoretical model of ongoing processes in the system and defined the characteristic critical parameters on the base of the model.
4. Be-BeO system formed in beryllium- water contact in the result of radiation-heterogeneous processes stimulates further radiolytic and radiation-thermal decomposition processes of water and has radiation-catalytic effect. These processes accelerate metal corrosion and lead to obtain of molecular hydrogen with high radiation-chemical yield in contact with environment. The obtained results are recommended both for characterization of the fact of obtaining dangerous hydrogen gas and corrosion in contact of metallic beryllium with water in nuclear reactors, as well as its further use in formation of effective radiation-catalytic systems based on direct Me-MeO contact.
5. Increase in resins concentration up to 15-20% causes increasing in its radiation resistance above 50% and it is closely connected with high defence capability of polycyclic aromatic compounds from radiation. Such kind of oil products with high radiation resistance allows production of materials which is applicable in radiational atmosphere.
6. It has been revealed dechlorination process of transformer oil with 14 mg/kg concentration of PCB in it (with 1,2÷1,4 quantum yield) under the influence of light with 200-300nm wave length. The obtained result can be used in solution of ecological problems related with PCB oils.
7. In the process of radiolysis of phenol solutions in water, the phenol conversion with molecule/100eV yield has been revealed. The observed results can be applied in treatment of water basins from toxic phenols with radiation technological method.
8. It has been revealed an increase for 4-5 times in quantum yield of molecular hydrogen in comparison with pure water in photolysis of water with presence of n-Al2O3. It has been defined that TiO2+nano-Al2O3 binary system has higher radiation-catalytic activity in the process of water radiolysis than its components and the speed of hydrogen formation at optimal mode increases up to W(H2)=5.56∙1014 molecule/g∙sec.

II ISSUE: RADIATION-INDUCED PROCESSES IN SOLIDS
1.It has been revealed increase in TlInTe2 crystal’s dielectric permittivity for three times, electric conductivity for 6 times and shift of transition to superion conductivity towards low temperature range at 50 Mrad of absorption dose of gamma radiation. It has been defined limit values of electric field and gamma radiation doses for the crystal and proposed the mechanism of the observed effects.
2. For the first time it has been defined stoichiometric breakdown in layered GaS crystal irradiated with H2+ ions with 140 keV energy and flux values of irradiation in which the amorphization process started. It has been defined that the crystal compound changes during irradiation in GaS crystal with H2+ ions at values of irradiation flux above 5∙1015 cm-2 and stoichiometry breaks down. After certain value of proton flux amorphization process also takes place in GaS crystal. On the base of model of interaction between protons and GaS crystal, limit doses of amorphization observed theoretically and practically coincide within the framework of errors.
3. In extremely high density polyethylene+CdS/ZnS and polypropylene+ CdS/ZnS compositions at 24-30% amount of concentration of binary aggregates, at 20-80 kQy values of gamma irradiation dose it has been defined radiation resistance according to their electrophysical properties.
4. For physical-mechanical properties, resistance to aggressive liquid environment the new elastomers obtained with thermal-radiation method on the base of polymer peroxide, metal oxide, polyester resin, carbon black and hydrogenated butadiene nitrile rubber can be applied in machine-building, oil-chemistry, automobile and other fields for production of cup, plug, densifying product.

III ISSUE: STUDY OF RADIOECOLOGICAL SITUATION IN THE TERRITORY OF THE REPUBLIC, STUDY OF INFLUENCE MECHANISM OF RADIATION FACTORS ON BIOLOGICAL SYSTEMS, PROTECTION OF LIVING ORGANISMS FROM THE INFLUENCE OF IRRADIATION AND DEVELOPMENT OF SCIENTIFIC BASES OF RADIATION SAFETY PROBLEMS
1. It has been studied the activity of antioxidant protection system in the second generation of some vegetable plants of which seeds exposed to γ-irradiation at different doses before sowing. It has been revealed that the ionizing irradiation at small dose range intensifies the formation of active forms of oxygen on plant leaves and in the result, cell membranes are subjected to large-scale destructions accompanied with increase of amount of malondialdehyde which is the peroxide oxidation product of lipids. In such condition the activity of antioxidant protection system of plants both accelerates synthesis of antioxidants as proline and causes activation of antioxidant enzymes. At high dose range the devastating impact covers both lipids and biological macromolecules.
2. It has been revealed that the productivity and product quality of wheat seeds within preliminary gamma irradiation at 250 Gy absorption dose have decreased.
3. It has been determined that the plant of absinth (Artemisia absinthium) possesses the property of accumulating natural radionuclides from soil by assimilating. The observed effect can be used in phytoremediation (recovery by plants) of radioactive polluted ecosystems.
4. The amplitude of characteristic wide EPR signal (g=2,32 and ΔH=320 Qs) observed in plant samples can be used in radioecological monitoring as a bioindication parameter. High values of the amplitude of EPR signal in the studied samples are consistent with high value (exposure dose rate) of radioactive contamination.
5. The results of the experiments performed on live objects (wheat sprouts, rats, mice, rain worms) allow to recommend the plant extracts of Hypericum perforatum L., Calendula officinalis L. and yarrow (Achillea millefolium L.) modified with polyvinylpirrolidon (PVP) as an immunostimulatory and radiopreventive biological active food additive, and also as a microfertilizer.
6. a. For the first time it has been developed database on background concentrations of polycyclic aromatic hydrocarbons in sediments of intensive oil-gas production areas in Azerbaijan part of Caspian Sea.
b. Studying the background concentrations of radioactive isotopes, heavy metals, polycyclic hydrocarbons and other harmful substances in groundwater in the industrial zone developed in south from Baku, it has been prepared database on physical and chemical parameters and heavy metals.
7. An optimum mode has been selected for decomposition of synthesized new sorbents from produced water with the method of radium sorption and a pilot device has been developed for decomposition.
8. Nuclear activation processes of nano SiO2 samples under the influence of epithermal neutrons and kinetics of decay processes of activated nuclei has been studied. It has been found that under neutron influence the electric conductivity of nano SiO2 samples sharply (3-4 order) changes and dependencies of this change on irradiation dose, temperature and electric field frequency have been determined.
9. a. It has been studied the kinetics of molecular hydrogen formation in radiation-heterogeneous decomposition of water on the surface of uranyl-silicate and pure silicate at the range of T=300-673 K of temperature.
b. It has been determined that though liquid fully covers the surface of uranyl-silicate of water, there occurs more effective energy transport process to water molecule by particles generated at solid phase and therefore molecular hydrogen yield appears to be much higher.
c. As rate of migration of energy carriers to surface level rises with temperature increase, molecular hydrogen yield increases as well.
10. For the first time it has been revealed the fact of accumulation of Be-7 isotope on plant cover under cosmic rays and water flow from high mountain glaciers in the territory of Sheki region of Azerbaijan Republic.

IV ISSUE: OBTAIN OF ENERGY CARRIERS, DEVELOPMENT OF SCIENTIFIC BASES OF UTILIZATION OF RENEWABLE ENERGY SOURCES IN ENERGY SUPPLY IN PRODUCTION AND HOUSEHOLD
1. It has been developed a self-contained solar heating unit for individual, public and industrial objects using hot water.
2. It has been studied the influence of pollination and shadowing on efficiency of solar collector during a day in climatic conditions of Baku. It has been determined that the maximum effect of shadowing rate is observed in the morning and evening hours and its influence on the efficiency becomes 5-6% during a day. For flat solar collector it has been defined the value of pollination rate at constant value of shadowing rate in Absheron peninsula conditions. Considering both of the two factors, it has been defined the values of solar radiation energy of flat solar collector that may be useful.