Measurement of urine absorbance which has been irradiate by a dose of ionising radiation with addition of Mn2+ should serve to find the dose of radiation. This method could work quickly and reliably for homogeneous irradiation of person or as a rough estimate of the dose which the person received during a radiation accident. This method should serve for quick classification of the person. The target of this thesis is to find out if the irradiated urine with the addition of a solution of manganese chloride will change absorbance according to radiation dose. And if urine can be used as a biological dosimeter. In the theoretical part I describe the basic areas related to the topic and target of my thesis. This part is divided to seven subchapters: ionising radiation, radiation protection, radiotherapy, particle accelerators, spectrophotometry, excretion and urine, and dosimetry and its methods. Methods of this thesis are not clear. I tried different procedures during experiments with different results. First, I always prepared samples of urine in tubes and irradiated it in a linear accelerator Clinac 2100C/D in České Budějovice, a.s. hospital with doses from 1 to 25 Gy. Before each measurement I had two sets of tubes with these doses: 0, 1, 2, 3, 5, 7, 10, 15, 20 and 25 Gy. The following procedure was different in each experiment. Sometimes I tried adding a solution of manganese chloride to all tubes at once. Sometimes I tried to adding a solution of manganese chloride to each tube separately. I added the solution to irradiated urine at various concentrations of solution (from 1 do 5 mols) and different amounts (from 1 to 3 ml). Another difference was the use of centrifuges. A centrifuge was use in about half of experiments. Other measurements were made without centrifugation.In discussion I propose recommended methods. I recommend measuring only without centrifuges. Each cell should be measured as soon as possible after irradiation and simultaneously as soon as possible after adding the solution of manganese chloride. Results of the thesis are not clear. Only some experiments which were measuring with centrifuge were clear. I can say that this method does not work when a centrifuge is used at any tested concentration of solution of manganese chloride. The absorbance of single doses of ionising radiation does not change and the values were the same when using 1M, 3M and 5M solutions of MnCl2. The resulting graphs from all experiments have a constant absorbance value of all measured doses. (subchapter 3.1).In the remaining experiments measured without the centrifuge the results were much more interesting. In some experiments the measured absorbance really changed with the dose of ionising radiation so the hypothesis of this study was confirmed. But the differences were too small for this method to be used for measuring radiation doses (subchapter 3.2).The results were compared with the results of the thesis ?Measurement of urine extinction in depending on ionising radiation? from author Š. Radová. She performed a similar experiment, but with a different indicator - FeSO4. 7 H20. It was found that the indicator FeSO4. 7 H20 is preferable to measuring doses of ionising radiation in urine. In conclusion I can say that the hypothesis of this study was confirmed, but the method could not be used in practice and irradiated urine with added MnCl2 indicator does not function as a biological dosimeter.
Identifer | oai:union.ndltd.org:nusl.cz/oai:invenio.nusl.cz:154663 |
Date | January 2013 |
Creators | KONEČNÝ, Jan |
Source Sets | Czech ETDs |
Language | Czech |
Detected Language | English |
Type | info:eu-repo/semantics/masterThesis |
Rights | info:eu-repo/semantics/restrictedAccess |
Page generated in 0.0753 seconds