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This paper summarizes measurements of the radioactivity of soil and plant samples from the part of the Łęczna-Włodawa lake district, which is under a re-naturalization project, in Lublin and Chełm provinces (Eastern Poland). The aim of the studies was to determine the concentrations of particular radionuclides in the soils and plants of this district. The total radioactivity is reported as well as the contribution of artificial radionuclides (Cs-134, C-137) whose presence is due to radioactive fall-out. The total radioactivity of the soil samples ranges from 100-900 Bq/kg, and that of plant samples from 100—1300 Bq/kg. Contamination by radiocesium depends on the migration of water.
This paper includes the results of measurements of natural radioactivity in building materials and raw building materials. The dose rate indoors was calculated on the basis of the contents of K-40, Ra-226 and Th-232 in building materials and the results were compared with literature data of measurements (in situ). The standard procedure for qualifying building materials for building houses designed for habitation was used.
Maria Skłodowska was born on November 7, 1867 in Warsaw (Poland). Her parents were teachers. Maria’s mother has died in 1878 of tuberculosis. In 1893 and 1894, respectively, Maria was awarded master’s degrees in physics and in mathematics from the Sorbonne University. In 1895 Maria married Pierre Curie. In 1897 their daughter Irene was born. Maria investigated rays emitted by uranium salts. She hypothesized that the radiation come from atom and called this phenomenon “radioactivity”. In 1898, Maria and Pierre discovered new radioactive elements polonium and radium. In 1902 she isolated pure radium chloride and defined radium atomic mass. In June 1903, Maria supervised by Professor Lippmann was awarded her doctorate in physics from the Sorbonne University of Paris after presentation of the thesis “Investigation of radioactive bodies”. In December 1903, Maria was awarded the Nobel Prize in Physics, along with her husband Pierre and Henri Becquerel, for their work on radioactivity. In 1904, the daughter Eve was born. On 19 April 1906, Pierre was killed in a road accident in Paris. In 1910 Maria isolated radium as a pure metal. She also defined an international standard for radioactive emissions (curie), published her fundamental results on radioactivity and textbook of radiology. She also defined the international pattern of radium. In 1911, she won her second Nobel Prize, this time in Chemistry, for her discovery of radium and polonium. In 1914 she was appointed director in the Radium Institute in Paris. During World War I, Maria became the director of the Red Cross Radiology Service and set up France’s first military radiology centre. In May 1932 she has attended the official opening ceremony of the Radium Institute in Warsaw. On 4 July 1934, Maria Skłodowska-Curie has died aged 66 years in Sancellemoz sanatorium (France) of aplastic anemia.
This paper presents the results of measurements of natural radioactivity of K-40, Ra-226 and Th-232 in building material as well as radon concentrations and dose rates in houses and outdoors. The mean absorbed rate in air outdoors from natural gamma radiation was found to be 40.2 nGyh'1. Doses inside houses made from particular materials were (nGyh '): brick - 102, prefabricate - 89, wood - 88. The mean equivalent concentration of radon indoors was 12 Bqm-3. The calculated annual effective dose equivalent per one statistical inhabitant of "Poland Green Lungs" is 1.61 mSv/year. The doses absorbed by the population in the northeastern region of Poland from natural sources of ionizing radiation are lower than the population-weighted world averages.
The results of studies of radioactive contamination of Borne Sulinowo military range is presented. Until 1991, this area was occupied by the former Soviet Army. No serious contamination with natural or artificial radionuclides has been found in the studied area. The activity of natural radionuclides such as 214Bi, 226Ra, 234Th, 224Ra, 228Ac and 214Pb in the soils ranges from 6-8 Bq/kg of soil, which is low when compared to industrial regions of Poland, where 18-36 Bq/kg of these radionuclides have been found. Also, contamination by 137Cs is considerably lower than in Eastern Poland. In about 70% of the studied samples, post-Chernobyl radiocesium contributed less than half of the total amount of this nuclide. It follows that post-Chernobyl fallout was low in the studied area. Moreover, the high level of l37Cs from global fallout in the examined samples manifests strong bonding of cesium in the surface layer of the soil.
Here are presented results of studies on vertical and horizontal migration of strontium 90Sr isotope in soil systems of Bug river valleys. Mean radioactivity of strontium in these soils was 26.15 ± 22.2 Bq/kg. Atmospheric precipitation of strontium on this area was 0.35 kBq/m2/cm. Radioactivity in soil profiles ranged from 17 to 130 Bq/m2/cm and the isotope was detected even at 30 cm depth. Some tendency to vertical migration of strontium towards the river was noticed. Obtained results were compared with concentrations of calcium and strontium in the soil. Any clear influence of these elements on the migration of strontium 90Sr was noticed.
Several components of sheep blood extensively catabolize nucleosides, including thymidine. Part of the radioactivity from tritiated thymidine, in whole blood cultures, is quickly rendered unincorporable as the compound is metabolized to thymine and further breakdown products. Thus, cells continue to proliferate without incorporating radioactivity from the medium. Furthemore, variability in the degree of catabolism varied from animal to animal, so that neither measurement of the depletion of radioactivity from the medium nor measurement of the amount of label incorporated into cultures can be used as a quantitative index of the cell proliferation or immunocompetence.
Studies of the contents of gamma emitters in samples of water and deposit taken from the Bug River (in Poland only) are presented. The total y-activity of deposits ranges from 120-650 Bq/kg and the average value is 350 Bq/kg. The elevated activity is chiefly due to the presence of natural radionuclides. The main artificial radionuclides are Cs-137 and Cs-134, whose contribution to the total activity ranges from 0.2 to 6%. The activity of water samples is low, namely 1.7-3.5 Bq/kg and is due to the presence of natural radionuclides. The heterogeneity of the distribution of natural and artificial radionuclides in the studied samples reveals the effect of economical and industrial activities on contamination of the Bug.
This paper presents the results of investigations of grass contaminated by 137Cs in eastern Poland. The influence of the site, potassium ion content, soil type and caesium from soil to plant transfer coefficient (TF) were examined.
This paper presents results of physical chemistry research on solutes leached from mine waste dumps. Radioactivity research of that solutes is also included, taking into consideration its usage in earth constructions of hydraulic engineering. The research was done on samples taken from eight coal mine waste dumps. Impact on the water environment of that solutes was assessed, together with their radioactivity effect.
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