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[en] Full text: Radiation dose and risk calculations for different radioisotope concentration stack heights and atmospheric stability categories have been carried out by the code CAP88-PC around the YPP environment by using the results of previous studies about maximum measured gross alpha activity in the flying ash samples as radioactive source. A modified Gaussian plume equation was used to estimate the average dispersion of radionuclides released from up to six emitting sources for a circular grid of distances and directions for a radius of up to 80 kilometers around the facility. The meteorological data obtained from Turkish State Meteorological Service for Yatagan region was processed to find out the stability array file consists of 4 different wind frequencies, one for each of the 16 wind directions on 6 Pasquill stability categories. 16 records were entered for each Pasquill stability category and wind frequencies. Pasquill stability classes used in the code are A: extremely unstable, B: unstable, C: slightly unstable, D: neutral, E: slightly stable, and F: stable. Dose and risk are estimated by combining the inhalation and ingestion intake rates, air and ground surface concentrations with the dose and risk conversion factors used in CAP88-PC. The effective dose equivalent is calculated using the weighting factors in ICRP (International Commission on Radiological Protection) Publication 26 (ICRP, 1977). Risks are based on lifetime risk from lifetime exposure, with a nominal value of 4E-4 cancers/rem. Doses and risks can be tabulated as a function of radionuclide, pathway, location and organ CAP88-PC also tabulates the frequency distribution of risk. The risk levels are divided into orders of magnitude from one in ten to one in a million. The maximum effective dose equivalent rates for each condition and their radiological effects have been interpreted. It is seen that these values are recommended by the International Commission on Radialogical Protection (ICRP) and have not any significant risk for public health around the plant environment
[en] Full text: Determination of the contents of light elements such as: H, B, N etc. in various objects is actual problem in many branches of a science, engineering, chemical and mining industry, and agriculture. The method of the prompt gamma activation analysis - PGAA, based on neutron capture gamma-ray spectrometry is the most suitable analytical method for determination of the contents of these elements in different complex compounds. The very wide range of a spectrum of prompt gamma radiation (from 0.1 MeV up to 11.4 MeV), which accompanies the capture of neutrons allows determining the majority of elements. In this work the results of creation of the device for PGAA and the developed technique for determination of some elements (such as nitrogen, hydrogen and boron) content are given. In the Institute Nuclear Physics AS UZ the authors have developed the experimental device using low-power radionuclide neutron source (californium-252) for study of prompt gamma radiation spectra. As a result of experiments the optimal construction materials and measurement geometry were found for investigation of whole spectra of prompt gamma radiation and the possibility of analytical application for determination of nitrogen in chemical fertilizers for agriculture, soil, grain and cereals. It has been shown that by use of scintillation spectrometry with NaI (Tl) detector (80 * 90 mm) it is possible to determine nitrogen, hydrogen and boron through their prompt gamma lines (10829 keV, 2223 keV and 478 keV respectively)
[en] Full text: In the site selection process, all site characteristics that could be acceptable from a safety viewpoint are considered. The site selection process is important from not only the safety point of view, but also economical concerns. Some of the countries have important difficulties in finding locations to build nuclear power plants. Because these countries are encountering different evidences during the site selection, such as seismic unstability, inadequate cooling water availability (river site case) and the difficulties of the transportation of heavy equipment etc. Site selection study is performed in three phases; site survey, site evaluation and site confirmation. The purpose of the site survey is to identify one or more site that are likely to be suitable for detailed characterization during the site evaluation phase. In the evaluation stage, in order to demonstrate whether the site is acceptable, the studies and investigations are focused on the one or more preferable sites. Finally in the site confirmation stage which is a pre-operational stage , the activities are accumulated in detail and performed during construction of the nuclear power plants. In Turkey the siting study is performed in accordance with the decree on pertaining to issue of licenses for nuclear installations.In fact, this decree is mainly adapted from the IAEA safety guides and NRC experiences. But the decree doesn't have selection procedures. These are defined in the related regulations
[en] Full text: Radon emissions that are enhanced by forthcoming geophysical events as earthquakes have been observed all over the World. Many of these observations have been carried out with several equipment using different techniques. In this study, radon concentrations were determined by collector method and solid state nuclear tracks detectors (LR-115 films). The data were obtained reading films that buried into sufficient depth of soil, using handmade 100 X magnification of digital microscope. Reading was performed by counting tracks that remained from alpha radiation of radon decay on films. In film process, they have been bath with 10 percent of NaOH solution. In other method to determine radon activity concentration is collector method. In the method thermal water samples were foamed and gas was taken into steel chamber that was vacuumed. In the chamber 600 volt electric was applied to the body of chamber and cupper plate that was insulated from steel. The thermal water sources and soils in the Cheshme fault zone were selected as study regions. The results obtained with the method of collector vary between 22.52 Bequerell L-1 and 0.21, and the results obtained with the method of film vary between 4920 track cm-2 and 200 track cm-2
[en] Full text: Due to the fact of long-term oil production some local polluted zones exist on Absheron peninsula. The reasons of this pollution vary depending upon the place of pollution. The territory of Romani Iodine plant was selected as the object of investigation. This area was polluted as a result of iodine production process as well as of the influence of stratal water coming with extracted oil. Iodine element is accumulated as other radionuclides in composition of stratal water extracted with oil from ground substratum. During the process of iodine separation from water for its usage in production, water is run through coal. After absorption process coal is placed in the open air. Being in the open air under the influence of rain and other external action coal looses its sorption ability and changes the natural radioactive background of the given territory. The task of the investigation is to determine the changed radioactive background and to set the reasons of this change. It has been observed that the radioactive background at this territory in the source differs from that one at the distance from the source. From the first stage of the investigation the territory was studied and numbered being previously subdivided to small areas. In numbered areas the radioactive background was measured at the distance 1 m above the ground surface by means of SRP - 88 dosimeter, the strength of exposure dose was determined and marked. After that the soil samples were taken at the depth of 10-20 m in the noted point by means of the dosimeter. It should be noted that in above mentioned areas firm soil existed together with the soft one. The samples are collected in special packets with their number, the place of taking and EDG. The natural radioactive background of the territory was measured in different points and so according to these measurements the radiological map of the territory was drawn up. Radionuclide content and activity of the samples were identified by gamma spectrometer
[en] Full text: The principle of analysis by Monte Carlo method consists of a choice of random variables of coefficients of an exposition doze capacities of radiation and data on activity within the boundaries of their individual density of frequency distribution upon corresponding sizes of exposition doses capacities. This procedure repeats for many times using computer and results of each round of calculations create universal density of frequency distribution of exposition doses capacities. The analysis using Monte Carlo method can be carried out at the level of radiation polluted soil categories. The analysis by Monte Carlo method is useful for realization of sensitivity analysis of measured capacity amount of an exposition dose in order to define the major factors causing uncertainty in reports. Reception of such conceptions can be valuable for definition of key categories of radiation polluted soil and establishment of priorities to use resources for enhancement of the report. Relative uncertainty of radiation polluted soil categories determined with the help of the analysis by Monte Carlo method in case of their availability can be applied using more significant divergence between average value and a confidential limit in case when borders of a confidential interval are asymmetric. It is important to determine key categories of radiation polluted soil to establish priorities to use reports of resources available for preparation and to prepare possible estimations for the most significant categories of sources. Usage of the notion uncertaintyin reports also allows to set threshold value for a key category of sources, if it is necessary, for exact reflection of 90 percent uncertainty in reports. According to radiation safety norms level of radiation background exceeding 33 mkR/hour is considered dangerous. By calculated Monte Carlo method much more dangerous sites and sites frequently imposed to disposals and utilization were chosen from analyzed samples of polluted soil
[en] Full text : In the photovoltaic material family, cadmium telluride is regarded as one of the most promising material for fabrication of high efficiency polycrystalline CdTe/CdS thin film solar cells because of its near-optimum band gap of about 1.46 eV and high optical absorption coefficient in visible range. The maximum efficiency of about 16.5 percent of the laboratory samples of polycrystalline CdTe based thin film solar cells was achieved by using nanostructured CdS:O window layer and the modified device structure. In spite of the large lattice mismatch between cubic CdTe and hexagonal CdS (nearly 9.7 percent) the CdTe/CdS solar cells are characterized by essentially high efficiencies caused by interdiffusion at the junction interface removing the lattice mismatch. To identify the structural mechanisms leading to the solar cell efficiency increase we have studied the effect of CdCl2 treatment on the output parameters of CdS/CdTe-based solar cells and crystal structure of the base layers deposited on glass substrates by different ways. In the first way both of CdS and CdTe layers were deposited by physical vapor deposition (PVD) method meanwhile in the second way the chemical bath deposition (CBD) and close-spaced sublimation (CSS) methods were used for CdS and CdTe films deposition, respectively. For the PVD structures. The average grain size of the film increases from 1 μm to 4 μm due to the lattice strain caused by macrodeformations and stacking faults. The maximum efficiency (ηA=10.3 percent) of solar cells on the basis of cadmium telluride layers deposited by PVD method corresponds to 0,35 μm CdRl2 thickness at CdCl2 treatment. CBD/CSS samples were exposed to CdCl2 vapor at 400 degrees Celsium for 5-7 min in vacuum chamber in the presence of 100 torr oxygen and 400 torr helium. As-grown CdTe films were characterized by clearly faceted surface morphology and an average grain size of about 3-4 μm. Unlike the thermally evaporated CdTe films, no considerable changes after CdCl2-treatment in the structural properties and surface morphology were observed for the CdTe films obtained by CSS method. The difference between the results on CdCl2-treatment can be explained by a lower concentration of defects and grain boundary area in CSS deposited CdTe films resulting in lower lattice strain energy which promote recrystallization and grain growth. As a result the CSS deposited CdTe films do not recrystallize at the temperatures and times used in the CdCl2 treatment
[en] The given article affects main principles and ways of establishing an international radiation protection standards in Azerbaijan. There is also mentioned about ICRP recommendations which are strongly used within the country. All these recommendations can de divided into several groups : a) Justification principle; b) The optimization principle; c) The dose-limitation principle. Also ICRP recommendations have scientific and medical character, issued as publication. There have been made a connection between Government Organizations, National Security and Radiation protection. Additional protection and safety objectives have been described in detail. At least final conclusion concerning the ways of improvement national radiation control had been offered.
[en] Full text : In this research, polarization resistance (Rp) and capacitance samples of Electroless Ni-P layer exposed to gamma radiation under H2O2 environment and then oxidized in temperature 673 degrees K under H2O environment were investigated by using frequency dependent complex impedances (FDCI) method. In order to measure FDCI of specimens, an alternating voltage with a sine wave pattern was supplied between the counter and sample electrodes by changing frequency from 1 MHz to 100 KHz. Two semi-circles were observed in cole-cole plot. One semi-circle for low frequencies from 1 MHz to 10 Hz, designated as the low frequency semi-circle, was observed on the larger real part of the impedance, while the second for high frequency up to 100 KHz designated as the high frequency semi-circle was observed in the smaller real part. Measured FDCIs and phase-angle for specimens of NI-P and NI-P oxidized are compared in the article. It is seen that the result can be concluded that Rp resistance and capacitance for sample of oxidized layer larger than non oxidized sample; that related on formation of oxide layer with double layer structure.
[en] Full text : It was early shown that 78,4Fe10,8Mo10,8C and 75,5Fe10Mo14,5C spinning ribbons, which contain ∼ 90 percent mass. of metastable ternary δ-phase (cP20, Ρ4132, β-Mn, a = 0,6327 - 0,6370 nm), reach the state of thermodynamic equilibrium under in situ high-temperature X-Ray diffractometry (HT XRD) conditions. According HT XRD data three-phase equilibrium fields η + β + γ, β + γ + ε exist among others on the solidus surface of the Fe-Mo-C system. This experimental result corroborated completely data of thermodynamic modelling, which have been obtained by CALPHAD-method on the base of Andersson's model of Fe-Mo-C system with using of Thermo-Calc applications modules. The fragment of the reactions scheme of the iron rich part of the Fe-Mo-C system in the temperature range of ∼1000...1600 K shown in this article.