Results 1 - 10 of 200
Results 1 - 10 of 200. Search took: 0.02 seconds
|Sort by: date | relevance|
[en] It has been studied the degree of structural disorder of layered crystals Ga S before and after implantation by hydrogen (H_2''+) with energy of 140 keV by Raman scattering method. From Raman spectra of layered crystals Ga S it is established that at hydrogen implantation up to dose below 5x10''15sm''-2 the position and intensity of the bands are kept, which is connected with stability of crystal lattice, but at 5x10''15cm''-2 dose the intensity of the bands decreases due to the increase in degree of the structural disorder
[en] It was studied the impact of mass and size effects on radiation-chemical yield of molecular hydrogen which is formed from the water radiolysis process under the influence of γ-quanta (60''Co, P=22 rad/sec) within the size (d=50, 100, 300†500 nm) and mass (m=0.01, 0.02, 0.06, 0.12 g) of silicon in Si+H_2O system. It was defined that, radiation-chemical yield of hydrogen decreases with the increase of silicon size and it is directly proportional to silicon mass in low values of the ratio of silicon to water mass, but there is saturation state in the values higher than 1/200
[en] This article presents the current state in the radioecological soil Issyk-Kul province of natural uranium. Found that the background radiation - exposure dose and artificial radionuclides in the soil of the coastal zone of the lake as a whole at the level of the background and the acceptance of lower standards except for natural technogenic and some natural areas. Radioecological this province is mild natural and industrial uranium province.We have previously established 10 experimental plots around Issyk-Kul and the measurement showed that the power of natural background radiation in the gamma radiation of the coastal lake zone is an average of 17 to 25 mR/h in some areas up to 40 mR/h. As the distance from the lake to the side slopes of its level in some places rises to 40 mR/h, especially in some mountainous areas, canyons, which are based on the rocks, granites and their fragments are small, red sand, with a slightly increased radioactivity. For small areas with high natural background radiation can be attributed to the beaches of the coastal zone v. Jenish, v. Ak-Terek, located on the southern shore of Issyk-Kul Lake. The radioactivity of 30 - 60 mR/h, and in areas with a high content of iron in the sand inclusions level exposure dose increases up to 400 mR/h. Small areas of the coastal zone of Issyk-Kul Lake, mostly mud deposits with characteristic brilliance giving high radiation background. These areas include: the beach v.Tosor - 40-50 mR/h, 10 km west of the coast v.Kaji-Sai - 32-40 mR/h, the shore around with. Toru-Aigyr - 30 mR/h, the coast around v.Tamchi - 40-50 mR/h. In general, cities in the Issyk-Kul basin Kara-Kol, Cholpon-Ata and Balykchy radiation situation quite well, the average exposure dose of gamma radiation does not exceed 20 - 22 mR/h, but in some places the use of crushed granite, as filler and construction material, the level of background radiation increases to 40-50 mR/h This indicates that these natural resources, without first checking the radiation is not recommended for use as building materials.There are also slight variations in the natural radiation background in different soil types of Issyk-Kul region, probably due to the inhomogeneous distribution of natural radio-nuclides, scattered in soil, terrestrial rocks, surface, ground water and other objects of the environment. As can be seen from the data for the gray-brown soils of its value varies between 20-28 mR/h, with an average - 22 mR/h, light-brown soils - 16-26 mR/h, with an average - 22 mR/h for the mountain-valley chestnut - 21-24 mR/h, with an average of 22 mR/h, for the mountain-valley chestnut - 18-21 mR/h, with an average - 20 mR/hr, for the mountain-valley dark chestnut 17-21 mR/h, with an average - 18 mR/h. The results of measurements of natural background radiation we compiled conditional schematic map of the exposure dose of external gamma radiation in the Issyk-Kul region.
[en] The samples of diesel fuel from natural oils of Azerbaijan were used as the research object. Laboratory studies were conducted on Co""60 gamma-source at dose rate of P=0,18 Gy/s at different absorbed doses D=15-153kGy. The results of chromatographic, IR-spectroscopic studies are given. Concentrations, radiation-chemical yields of the obtained gases are established. Density of fuel samples before and after irradiation was determined at different absorbed doses and estimated their radiation resistance.Diesel oil with a boiling temperature 180-360 degree C, density of 0.790-0.860 g/cm""3 is obtained from virgin oil followed by hydrotreating and dewaxing. The best diesel oil is considered light engine fuel with boiling temperature 230-350 degree C, consisting of 60 percent kerosene fractions boiling up to 300 degree C and 40 percent heavier straw fractions boiling at the range of 290-350 degree C. The ability of fuel components to keep its chemical composition under operating conditions within temperature change, radiation, under metal influence is of important practical significance. Radiation influence can be accompanied by chemical transformations: break, displacement of chemical bonds, formation of free radicals, gas release, formation of double bonds and polymerization. The materials resistant to radiation influence must have the ability to absorb energy without excessive ionization.We studied the effect of radiation on operational performance of diesel under static conditions in the usual manner before and after irradiation. Earlier, the results of experimental studies of radiation-chemical transformation of synthetic oil of oil-bituminous breed were presented.The aim of the work is the study of radiation resistance of diesel oil from the oil of Azerbaijan. The results of such research allow estimating the radiation resistance of fuel, revealing the influence of irradiation on the overall composition of fuel and the possible changes in the quality of fuel.Conducted studies showed that chemical processes, density change occur in diesel oil within the absorbed doses 15-153 kGy. The effect of radiation influence on hydrocarbons of fuel depends on chemical structure, fuel composition. Within the combustion the hydrocarbons are oxidized so fast that the radiation influence is negligible. When the formation of radicals slow down at low temperatures, a small amount of seal products are formed in hydrocarbon medium as a result of radiation. The processes occurring due to radiolysis can continue long after the termination of irradiation which leads to the change of fuel composition. As a result, the operating ability of oil fuel deteriorates at an ambient temperature. The negative effect of fuel irradiation which is in contact with atmospheric oxygen is more at higher temperatures. In the future, it will be able to select such composition of oil fuel which will withstand the effect of radioactive irradiation at high temperatures by changing hydrocarbon composition of oil products due to minor changes in the composition and introduction of additives
[en] In recent work the results of radioecological research of the territory of Sabunchu region of Baku are presented.As a result of dosimetric investigation it is revealed that the maximum values of exposition dose power exist in the territory of the former lo dine plant in the settlement of Ramana (up to 11,0 μR/hour). It is established that in all soil samples prevails ''40 K (239-524 Bq/kg)
[en] The regularities of removing chloroform (CHCl_3) from its water solutions under the influence of ionizing radiation were studied. It is shown that the decrease of the concentration of chloroform with increasing absorbed dose occurs. The degree of decomposition of chloroform is about 95 percent at 6kGy.Chlorinated hydrocarbons are forming during the chlorination of water in the water disinfection process. A number of chlorinated compounds are formed in the process, but the main of them are trichloromethane.Traditional methods are used for the purification of potable water from the chlorinated compounds, as well innovative methods based on the use of UV and ionizing radiation. In the process of removing of trichloroethylene and tetrachloroethylene from water solutions under the influence of electron beam was studied. Kinetic modeling based on the reaction of intermediate particles of water radiolysis with doped chlorinated molecules was carried out for the clarification of dechlorination mechanism. In the reaction of hydroxyl radicals and hydrogen atoms with chloroacetone (dichloroacetone and tri chloroacetone) was studied by pulse radiolysis method. Appropriate constant of reaction rate constants of e_q, OH and H radicals with above mentioned molecules were defined. In constants of radical reaction rate and electrons, forming in the radiolysis of water with molecules of 4-chloro phenol were defined by pulse radiolysis method. In the process of cleaning waste and drinking water from methane halogen (CHCl_3, CHBrCl_2, CHBr_2Cl, CHBr_3) was studied.It was shown that, the degree of transformation of chloroform increases with an increase of absorbed dose and reaches to 95% at 6kGy dose. Similar results were obtained for the process of radiolytic transformation of other halogen methanes.The aim of this work is the study of kinetic regularities of radiolytic degradation of chloroform in water solution at various initial concentration of chloroform.
[en] In the paper it is studied the influence of gamma irradiation and annealing on optic properties of gallium sulfide in IR spectrum range (wavenumber of 4000-400 cm''-1). Comparative analysis of IR spectra of original, γ-irradiated and annealed samples of gallium sulfide shows that, change in temperature, annealing condition and selection of γ-irradiation (140 krad) leads to modification of the structure. The obtained data suggest that the effect of radiation change in IR absorption occurs as a result of defect reconstruction in band gap of the crystal and concentration of photosensitivity centers and their hole filling
[en] The change of ph, chemical oxygen demand (COD) and formation of CO_2 at radiolysis of water solution of phenol in presence of nano-γ-Al_2O_3 within the absorption dose range of 0-400 kGy has been studied. The existence of Nano-- Al_2O_3 does not significantly affect the decrease in COD with the growth of adsorbed dose, but causes to reduction in concentration forming carbon dioxide. ph is strongly reduced in homogeneous system. ph changes relatively low in the presence of Nano-γ- Al_2O_3.Despite the intensive researches of radiolytic decomposition of phenol in water solutions, heterogeneous radiolysis of the system has been studied insufficiently. Particularly the influence of nanoparticles on radiolytic decomposition of phenol in water solutions has been weakly studied.In the work it has been studied the change in ph indicator, chemical oxygen demand (COD) and formation of CO_2 at radiolysis of water solution of phenol in presence of nano- γ Al_2O_3 within the absorption dose range of 0-400 kGy.The kinetic curves of changes of ph of the irradiated system, including radiolysis of homogeneous system of phenol-water, systems of nano-γ Al_2O_3 with and without sample rotation. ph changes relatively low in the presence of nano-γ Al_2O_3 in the system. Apparently, part of acidic liquid products is adsorbed on the surface of nano-γ Al_2O_3 . Unexpected change in ph is observed in the case of sample rotation. In this case decrease in ph is less than above mentioned two cases. The obtained results show the additional adsorption of acids on the surface of nano-γ Al_2O_3 at rotation in centrifuge.The kinetic curves of the changes in COD of the irradiated systems, including radiolysis of homogeneous system of phenol-water, systems of nano-γ Al_2O_3 with and without sample rotation.
[en] Sample preparation of soil samples (reference material) in a microwave oven using the EPA - 3051 methods showed that, with microwave decomposition, the extraction coefficient of metals from the soil improved and sample preparation time is drastically reduced.
[en] Herein, it has been presented the results of phenological observations, and also investigated the dynamics of dose-dependent changes in the amount of free proline in beans, eggplant, cucumber, tomato, as well as in potato, the seeds, and roots, which were processed with γ rays in the sterilization dose before sowing. It has been shown that pre-sowing irradiation in high doses increases the content of proline in all studied plants. It has been established that the growth and development of plants slow down as the dose increases. It has been shown that potato tubers irradiated in a sterilization dose are not suitable for subsequent sowing.