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Abstract
In the Lower Silesia region, in the vicinity of Kletno town (near K
odzko), there are remainders of uranium ores being mined there, such as dump sites, abandoned pits and the like. Extensive research has indicated an increase in radioactivity there. The present research was aimed at defining the radioactive contamination in the neighborhood of Kletno. The research involved gauging the radiation background, especially at the mine dumps and measuring the concentration of natural radioactive isotopes and Cs in the rocks and soil. Besides, the concentration of radium isotopes in waters was determined. Two spots only were found with higher radiation levels. A method for dealing with radiation hazards is proposed. Water analyses have indicated that flushing of radium isotopes from the rock-mass and the dumps is not significant. Therefore, it can be concluded that uranium ore mining in the region of Kletno has not caused any significant radioactive contamination.
Abstract
A sensitive procedure for the simultaneous determination of trace levels of osmium and ruthenium in platinum, by thermal neutron activation analysis utilizing γ-ray spectrometry, was developed. The radiochemical separation method utilized perchloric acid for a selective oxidation of osmium and ruthenium to the volatile tetroxides. The distillation of the tetroxides greatly reduced the radiation hazard presented by the bulk of the activities in the matrix. Activities of 15-day191Os and 40-day104Ru were measured by accumulation of pulses from a 3″ diameter NaI(Tl) crystal detector. Analyses of γ-ray spectra were achieved using digital computer techniques. The procedure provided analyses for a high purity platinum stock of 0.032±0.007 ppm Os and 0.044±0.005 ppm Ru.
Abstract
The concentration of 226Ra, 232Th and 40K has been determined by 
-ray spectrometry. The measured activity in the selected building materials and by-products of coal fired power plants ranges from 21.5 to 91.3 Bq·kg–1, 15.4 to 63.2 Bq·kg–1 and 83.2 to 683.9 Bq·kg–1 for 226Ra, 232Th and 40K, respectively. The results were compared with the reported data of other countries and with the world average activity of soil. The radium equivalent activities values of all building materials are lower than the limit of 370 Bq·kg–1, equivalent to a -dose of 1.5 mSv·y–1. The values of the external hazard index and the internal radiation hazard index are less than unity.
Abstract
South Africa signed and ratified the Comprehensive Nuclear Test-Ban-Treaty (CTBT) and accordingly made commitments to the Organization (CTBTO). Of the obligations are the establishment of a Radionuclide Laboratory, the design, installation and operation and maintenance of a radionuclide particulate and noble-gas monitoring station and the nomination of one radionuclide specialist South African to serve on an international team for On-Site Inspection (OSI). The last to provide expertise when the worldwide monitoring network provides strong indications that an illegal nuclear test has been performed at the territory of a State Party. The inspection team will be equipped with amongst others radiation monitors and nuclide specific measuring equipment limited to report on specific radionuclides agreed upon by all State Parties. In real-time operational circumstances one may assume that all members of the team will not be registered radiation workers and accordingly be regarded as members of the public when radiation hazard is to be evaluated. In this paper we try to categorize the radionuclides of interest and evaluate the radiological risk to the OSI-team due to inhalation of airborne radioactive particulate matter during the survey at the site of an anticipated nuclear test. From this study recommendations will be made to the CTBTO for possible implementation of portable sampling and analysis equipment to allow on-site evaluation of the potential internal exposure of OSI-team members.
Summary
Samples of limestone, sand, marble, clay brick, red brick, gypsum, Portland cement and white cement collected from upper Egypt used in building manufacturing have been analyzed for the natural radionuclides 226Ra, 232Th and 40K usingg-ray spectrometry. The specific concentrations for 226Ra, 232Th and 40K, ranged from 20-88, 13-115 and 54-304 Bq/kg, respectively. The average specific activities of these radionuclides were compared. Higher values of 226Ra and 232Th could be noticed in marble while that of 40K was in red bricks. Radium equivalent activities, dose rate and the annual gonadal dose equivalents AGDE were calculated for the measured samples to assess the radiation hazard arising from using those materials in the construction of dwellings. The radioactive heat production values of the selected materials have also been determined. They vary from a minimum of 0.41 for white cement to a maximum of 5.52mW/m3 for marble samples. The calculated heat-production values are quite similar to those estimated in Corsica.
Abstract
Usually neutron activation analyses are performed in point-source geometry. However, specially designed irradiation positions and carefully planned measuring conditions enabled the activation and analysis of samples with weights up to several tens of kilograms. A dedicated character of irradiation and of measuring conditions was the main reason for a very limited application of such activation analysis. The use of routine irradiation facilities and standard conditions for analytical gamma-spectrometric measurements is described. Starting with samples of some hundred milligrams usually used in activation, through multi-gram samples to several hundred gram samples, irradiation and measuring conditions were studied and tested for development of the method. This work began in 1991 in Denmark, using the Danish DR-3 reactor. Since then different aspects of the method have been investigated on 6 reactors; in Denmark on DR-3, in Austria on Triga-MkII (in Vienna), and Astra (in Seibersdorf), in the German Federal Republic on FRG-1 in Geesthacht, in Norway on Jeep II (in Kjeller), and in Kazakhstan on VVR-K (in Alatau). Altogether more than 1000 samples have been irradiated and measured. In total, the roughly 30 kg of irradiated materials included almost 300 large samples of more than 30 gram weight. The following theoretical and practical aspects were investigated during the work: theoretical problems concerning neutron self-absorption in common organic and inorganic materials, as well as gamma-attenuation during the measurement. From a more practical point of view: health physics and radiation hazards during irradiation, measurement, transportation and storage of samples with several hundred grams weight. Special requirements to irradiation containers were formulated and various containers were tested. Main advantages and drawbacks of the method are discussed.
Abstract
This study presents the high purity germanium (HPGe) gamma spectrometric measurement of natural radioactivity mainly due to 226Ra, 232Th and 40K in soil samples collected in Ferozepur and Faridkot district of Punjab, India. 226Ra activity varied from 28.6 to 51.1 Bq kg−1 with the mean of 39.7 Bq kg−1. The range and mean activity of 232Th were 42.9–73.2 and 58.2 Bq kg−1, respectively. 40K activity was in the range of 470.9–754.9 Bq kg−1 with the mean of 595.2 Bq kg−1. The air kerma rate (AKR) at 1 m height from the ground was also measured using gamma survey meter in all the sampling locations, which was ranging from 92.1 to 122.8 nGy h−1 with the mean of 110.6 nGy h−1. The radiological parameters such as Raeq and activity index of the soil samples were also evaluated, which are the tools to assess the external radiation hazard due to building materials. The mean and range of the Raeq values were 168.7 and 132.9–210.4 Bq kg−1, respectively, whereas the activity index varied from 0.5 to 0.8 with the mean value of 0.62. These indices show that the indoor external dose due to natural radioactivity in the soil used for the construction will not exceed the dose criteria. The AKR was also evaluated from soil activity concentration and altitude correction of cosmic radiation contribution. The statistical tests such as Pearson correlation, spearman rank correlation, box and whisker plot, the Wilcoxon/Mann–Whitney test and chi-square test, were used to compare the measured AKR with evaluated AKR, which indicates good correlation.
Szemléletváltozás az alsó végtagi érrekonstrukciók gyakorlatában a Szegedi Tudományegyetem Érsebészeti Osztályán
Paradigm shift in the vascular surgery of the lower extremity at the Department of Vascular Surgery, University of Szeged, Hungary
interventions. J Endovasc Ther. 2008; 15: 680–687. 26 Kim JB, Lee J, Prk K. Radiation hazards to vascular surgeon and scrub nurse in mobile fluoroscopy equipped hybrid vascular
of electrical systems in operating rooms and evidences on radiation hazards provide researchers to more investigate about the issue. Although there are several studies about the evaluation of electromagnetic waves intensity around electrical
