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Radioactivity of granitoids of the Krkonoše-Jizera pluton
Černík, Tomáš ; Goliáš, Viktor (advisor) ; Matolín, Milan (referee)
2. SUMMARY This thesis is focused on the natural radioactivity of the Krkonoše pluton, which is divided in 6 particular types of granite: the Jizera, the Liberec, the Fojtka, the Tanvald, the Harrachov, the Krkonoše ones. The goal of the thesis was to compare these values and find out whether there was an unlike element (U, Th, K) content difference. Based on literature data about the Czech and Polish part of pluton, there was assigned data of the analysed samples (of contents of K, U, Th) to each type of granite. The literature data was refined on the base of the current knowledge. The localized collection points were assigned to the particular types of the Krkonoše - Jizera granitoids. The analytic data collection was statistically evaluated. On the base of the statistic data evaluation significant differences of the radioactive element content of the particular types of granite was proved. The most radioactive one is the Harrachov granite. The Tanvald one has a distinctively anomalous ratio of U to Th higher than 1. The other types of granite have only an average level of radioactivity. There was also checked a significant aerial gamaspectrometric anomaly in the south - west direction of Hejnice. There was made a field gamaspectrometric measurement, which did not prove the significant increase in an...
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Changes of volume activity of radon in soil gas in dependence on the meteorological parameters
Hrušková, Gloria ; Matolín, Milan (advisor) ; Jáně, Zdeněk (referee)
This work engages in radon in soil gas, measuring its volume activity and atmospherical influences on its volume activity. Atmospherical (or meteorological) influences are a pressure, temperature and moisture of the air, wind and its velocity, a condition of the sky and a rate of precipitation. The measurement results from the period 2000-2012 done by the Charles University in Prague, Faculty of Natural Science (The Institute of Engineer Geology, Hydrogeology and Applied Geophysics, Department of Applied Geophysics) in the radon comparisoning areas Cetyně, Bohostice, Buk were used for the assessment. Powered by TCPDF (www.tcpdf.org)
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Radon daughter products absorption by filters
Šálek, Ondřej ; Jáně, Zdeněk (advisor) ; Matolín, Milan (referee)
The work is engaged in effect of short-lived radon (222 Rn) daughter products on measurement of radon volume activity in soil gas. Solid radon daughter products 214 Po and 218 Po transform by α-decay and influence measurement of radon volume activity in soil gas. This effect was investigated by experimental measurement of radon volume activity in soil gas at the Buk radon reference site in Central Bohemia. At each particular point of radon reference site, three values of radon volume activity were determined by measuring; without filter, with automobile petrol filter and with micro-fibrous filter AFPC type. Experimental measurement demonstrates that both of applied filters have near the same effect on measured values of radon volume activity in soil gas. The difference between radon volume activity values got by measuring without filter and with filters is low, in order of measurement error. Experiment did not evidence necessity of using filter for measuring radon volume activity in soil gas. Radon volume activity measurement error is in order of several kBq.m-3 . This fact brings uncertainty into obtained results. The absence of theoretically possible high content of solid radon daughter products in soil gas samples may be explained by possible adsorption of these particles on sampling and soil...
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Determination of photon dose equivalent rate by means of field multichannel gamma-ray spectrometers GS-256 and GR-320, and by radiation detector Gamma-Scout.
Mokrá, Zuzana ; Matolín, Milan (advisor) ; Chalupa, František (referee)
Práce se zabývá porovnáním dvou terénních geofyzikálních přístrojů na měření záření s radiologickým přístrojem. Vrámci řešení úkolu proběhly měření radioaktivity na geologických lokalitách s nízkou, střední a vysokou radioaktivitou přenosnými mnohokanálovými gama spektrometry se scintilačními detektory NaI(Tl) 76x76 mm a pomocí přístroje Gamma-Scout s malým Geiger-Müllerovým počítačem. Jednotlivými přístroji byly stanoveny hodnoty v jednotkách příkonu fotonového dávkového ekvivalentu (Sv/h) a ty pak srovnány. Byly očekávány odchylky v naměřených datech. Odchylky byly různé pro rozdílné způsoby výpočtu přikonu fotonového dávkového ekvivalentu z naměřených dat. Z terénních výsledků vyplývá, že výsledky jednotlivých přístrojů lze porovnávat, přičemž rozdíly jsou zapříčiněny různou detekční účinností a různou kalibrací jednotlivých přístrojů.
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Gamma radiation of geological objects and their localization by radiometric measurement
Šálek, Ondřej ; Matolín, Milan (advisor) ; Mojzeš, Andrej (referee) ; Gnojek, Ivan (referee)
This thesis deals with gamma-ray field of size-limited uranium objects and with possibilities of their localization by a field radiometric measurement. The gamma-ray field attenuates progressively with distance from the ground source of radiation. The applied method of radiometric survey plays an important role in localization of a radioactive object. The gamma- ray field of uranium anomalous objects was studied for variable signatures of ground anomalous objects and different methods of gamma-ray survey by using mathematical modelling. The method of modelling was derived from fundamental theoretical laws describing the gamma-ray field of a point source. The verification of applied mathematical modelling was carried out by the comparison of calculated model of the gamma-ray field at three real uranium anomalous objects with experimental data of ground and mini-airborne measurement. Mini-airborne measurement was realized by the prototype of a gamma spectrometer Georadis D230A. This instrument is characterized by relatively high sensitivity compared to previously used similar devices. Airborne platform was a hexacopter Kingfischer. One of the aims of this thesis was to assess the applicability and technical capacity of D230A instrument. Calculated values of the gamma-ray field at different detection...
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Gamma radiation of geological objects and their localization by radiometric measurement
Šálek, Ondřej ; Matolín, Milan (advisor) ; Mojzeš, Andrej (referee) ; Gnojek, Ivan (referee)
This thesis deals with gamma-ray field of size-limited uranium objects and with possibilities of their localization by a field radiometric measurement. The gamma-ray field attenuates progressively with distance from the ground source of radiation. The applied method of radiometric survey plays an important role in localization of a radioactive object. The gamma- ray field of uranium anomalous objects was studied for variable signatures of ground anomalous objects and different methods of gamma-ray survey by using mathematical modelling. The method of modelling was derived from fundamental theoretical laws describing the gamma-ray field of a point source. The verification of applied mathematical modelling was carried out by the comparison of calculated model of the gamma-ray field at three real uranium anomalous objects with experimental data of ground and mini-airborne measurement. Mini-airborne measurement was realized by the prototype of a gamma spectrometer Georadis D230A. This instrument is characterized by relatively high sensitivity compared to previously used similar devices. Airborne platform was a hexacopter Kingfischer. One of the aims of this thesis was to assess the applicability and technical capacity of D230A instrument. Calculated values of the gamma-ray field at different detection...
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An Application of Unmanned Aerial Vehicles in Airborne Radiometry
Dědek, Jiří ; Šálek, Ondřej (advisor) ; Matolín, Milan (referee)
This thesis deals with the use of Unmanned Aerial vehicles (UAV) in radiometric survey. The main goal of this work is to review characteristics of four selected UAV and parameters of employed detectors compared to the classical airborne and ground radiometric survey. Four selected UAV were assessed, hexacopter "Kingfisher" with the detector BGO (Bi4Ge3O12) of the volume 0,2 cm3 , the octocopter "Arducopter" with the 1 cm3 CTZ (CdZnTe) detector, helicopter "Yamaha RMAXG1" with 1,8 l NaI(Tl) detector and airship "ACC15X" with 2,7 l NaI(Tl) detector. Payload capacity, detector sensitivities, flight speed, flight altitude, endurance for one charged battery or full fuel tank and wind resistance were compared among the mini- airborne instruments. The estimation of UAV radiometric data quality was derived from the sensitivity of the detectors, the flight altitude and flight speed. Estimated UAV radiometric data quality was compared to classical airborne and ground typical radiometric data quality. Three selected UAV with a certain altitude and flight speed would achieve a comparable data quality as a classical airborne survey in the altitude of 80 m and flight speed of 50 m/s. Specifically it is hexacopter "Kingfisher" with a scintillation detector D230A at altitude of 40 m and speed of 1m/s, helicopter...
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Radioactivity of the rock and the environment in selected underground areas and its impact on human health
Thinová, Lenka ; Matolín, Milan (advisor) ; Holý, Karel (referee) ; Neznal, Martin (referee)
The thesis is focused on measurement and assessment of absorbed doses of radiation in caves of the Czech Republic, out of which some exhibit high activity concentration of radon in air. This thesis presents an analysis and recommendations based on measurement results obtained in the underground caves over the past 10 years. The focus is on defining the sources of irradiation within the cave environment (and in areas used for speleotherapy), considering their potential health effect, including the variable dependence of external and internal irradiation influences. All of the measurements had as an objective to verify, and where possible improve, the existing methodology for assessing and calculating the dose from radon in underground spaces. The main issue that had to be resolved was whether a numerically specified cave factor value is applicable to all underground areas. The research measurements were carried out in all available show caves and in several underground areas, and were based on the initial results from an aerosol measurement campaign. Two caves (the Bozkov Dolomite Caves and the Zbrašov Aragonite Caves) were selected for advanced long-term measurements. A large number of long-term and short-term studies were carried out. The most important results for cave environments were: the...
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Changes of volume activity of radon in soil gas in dependence on the meteorological parameters
Hrušková, Gloria ; Matolín, Milan (advisor) ; Jáně, Zdeněk (referee)
This work engages in radon in soil gas, measuring its volume activity and atmospherical influences on its volume activity. Atmospherical (or meteorological) influences are a pressure, temperature and moisture of the air, wind and its velocity, a condition of the sky and a rate of precipitation. The measurement results from the period 2000-2012 done by the Charles University in Prague, Faculty of Natural Science (The Institute of Engineer Geology, Hydrogeology and Applied Geophysics, Department of Applied Geophysics) in the radon comparisoning areas Cetyně, Bohostice, Buk were used for the assessment. Powered by TCPDF (www.tcpdf.org)
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