National Repository of Grey Literature 23 records found  1 - 10nextend  jump to record: Search took 0.01 seconds. 
Experimental Investigation of the Neutron Field in an Accelerator Driven Subcritical Reactor
Zeman, Miroslav ; Janda,, Jiří (referee) ; Chudoba,, Petr (referee) ; Katovský, Karel (advisor)
This dissertation focuses on irradiations of a spallation set-up consisting of more than half a ton of natural uranium that were executed by a 660 MeV proton beam at the Joint Institute for Nuclear Reserch in Dubna. Two types of irradiations were arranged: with and without lead shielding. Both types were arranged with threshold activation detectors (Al-27, Mn-55, Co-59, and In-nat) located throughout the whole set-up both in horizontal and vertical positions and activated by secondary neutrons produced by spallation reaction. The threshold activation detectors were analysed by the method of gamma-ray spectroscopy. Radionuclides found in the threshold detectors were analysed and reaction rates were determined for each radionuclide. Ratios of the reaction rates were determined from irradiation of the set-up with and without lead shielding. Subsequently, the neutron spectra generated inside the spallation target at different positions were calculated using Co-59 detector. The experimental results were compared with Monte Carlo simulations performed using MCNPX 2.7.0.
Transmutation of spent nuclear fuel with using accelerator driven systems
Máca, Pavel ; Král, Dušan (referee) ; Zeman, Miroslav (advisor)
This bachelor thesis deals with the analysis of neutron spectra in the reactors with liquid salts. The teoretical part contains a brief description of the nuclear fuel cycles. In the theoretical are further described the reactors of IV. generations. Here are the reactors on the basis of liquid salts described in detail. The practical part of the bachelor thesis is focused on the analysis of neutron spectra in set-ups performer from solid salt. Concretly, the salts NaCl and KCl were analysed by means of the computational codes TALYS and MCNP.
Neutron sources in science and industry
Andrýsek, Jan ; Zeman, Miroslav (referee) ; Král, Dušan (advisor)
This bachelor thesis is composed of literature review on the topic of neutron sources and experimental component discussing the reaction rate in an experimental model of a neutron source dependent on the isotope in used foil. The most used neutron sources in the world and in the Czech Republic are mentioned. The creation of neutrons in radionuclide sources in AmBe and PuBE, nuclear reactors, spallation sources and fusion neutron generators are described, together with their utilisation in research and industry. The practical part contains description of the design (\(\gamma \), n) of a neutron source in MCNP programme and its consecutive calculation using the Monte-Carlo method. The input for nuclear reaction are electrons accelerated onto energy of 70 MeV. These electrons strike the target, where the effect of braking radiation generates gamma rays. Radiation integrates with the nuclei of the convertor from beryllium oxide or lithium salt. The results analysed and discussed are used from experimental measurements in Yerevan for foils from isotopes 197-Au, 209-Bi and 59-Co. These foils were used in models with convertors from Beo and LiCl.
Characterization of the neutron AmBe source using threshold activation detectors
Burian, Jiří ; Zeman, Miroslav (referee) ; Král, Dušan (advisor)
Neutron activation analysis is used to characterize an unknown neutron field source or material of unknown composition. Using known reactions that take place in the activation detector due to the action of the neutron field, their measurement and evaluation, we can describe the composition of the source if we know the material composition of the activation detector, or, conversely, if we do not know the materials from which the activation detector is made, we can find out if we put this detector of unknown composition into the action of neutron radiation of known origin.
Nitric oxide - an indicator for severity of injury in polytrauma
Beitl, Evžen ; Hoch, Jiří (advisor) ; Cvachovec, Karel (referee) ; Zeman, Miroslav (referee)
- Part I (clinical study) Background: Patients with injuries to multiple organs or organ systems are in a serious risk of shock, multiorgan failure and death. Although there are scoring systems available to assess the extent of polytrauma and guide prognosis, their usefulness is limited by their considerably subjective nature. As the production of nitric oxide (NO) by many cell types is elevated by tissue injury, we hypothesized that serum concentration of NO (and its oxidation products, NOx) represents a suitable marker of polytrauma correlating with prognosis. We wanted to prove that nitric oxide can serve as an indicator for severity of injury in polytrauma. Methods: We measured serum NOx and standard biochemical parameters in 93 patients with various degrees of polytrauma, 15 patients with minor injuries and 20 healthy volunteers. Results: On admission, serum NOx was higher in patients with moderate polytrauma than in both controls and patients with minor injury, and it was even higher in patients with severe polytrauma. Surprisingly, NOx on admission was normal in the group of patients that required cardiopulmonary resuscitation or died within 48 hours after admission. In groups where it was elevated on admission, serum NOx dropped to normal values within 12 hours. Blood lactate levels on...
The analysis of laboratory X-ray device using possibilities and detection to ensure the entery into nuclear power plant.
Vlk, Petr ; Zeman, Miroslav (referee) ; Varmuža, Jan (advisor)
The thesis deals with the use of X-ray device for analysis of imported objects when entering a nuclear power plant. It describes the principles of X-ray generation and detection and techniques used in current X-ray devices. The thesis includes analysis of legislative requirements related to the safety of nuclear power plants and operation of X-ray devices. The benefit of the thesis is a proposed laboratory task using the Heimann HI-SCAN 6040-A X-ray device, which demonstrates detection and differentiation of analyzed objects and various types of materials. An integral part is the verification of the dose rate limits near the laboratory X-ray device, based on the knowledge of the legislative requirements.
Investigation of Thorium Utilization in Accelerator Driven Nuclear Reactors
Král, Dušan ; ČR, Petr Chudoba, ÚJF AV (referee) ; Zeman, Miroslav (advisor)
This thesis deals with the idea of using accelerator driven systems for thorium transmutation into the fissile material, which can be utilized in the accelerator driven systems and in thermal nuclear reactors. Thorium occurs on Earth only in fertile isotope Th-232. It can be converted to fissile U-233 by neutron capture and subsequent beta decay. The experimental part handles the data measured by the irradiation of four thorium samples by the secondary neutrons in the QUINTA spallation target, which was irradiated with 660~MeV protons. Reaction rates for the fission and spallation products were estimated using gamma spectroscopy and activation techniques. Furthermore, Pa-233 production rates were also determined in all experimental samples. Pa-233 and fission production rates were calculated in all experimental samples using the MCNPX transport code and evaluated nuclear data for high-energy reactions. The experimental results are of a great importance for the future investigation of thorium in the accelerator driven system concept, validation of Monte-Carlo based calculation codes and validation of high-energy nuclear models.
Analysis of the requirements for Mobile Monitoring System foe elderly people living in home background
Hrabalová, Klára ; Fiala, Radek (advisor) ; Zeman, Miroslav (referee)
In the thesis the author deals with the Mobile Supervisory System Senior Inspect, which allows monitoring of elderly people living in home background. Monitoring makes use of biological and general technical values, which are wirelessly transported and digestedly displayed in a notebook monitor. The author focuses on the analysis of the requirements, she puts forward the metodology of aplications of the monitoring system. Next the author endeavours to determine the requirements of the monitoring system and extending the whole system. She describes the desk of Senior Inspect 24/7 and checklist created for it. At the conclusion of her thesis the author highlights use of the monitoring system. The findings of this thesis should help when the monitoring system is put into practice.

National Repository of Grey Literature : 23 records found   1 - 10nextend  jump to record:
See also: similar author names
6 ZEMAN, Marek
14 ZEMAN, Martin
8 ZEMAN, Michal
6 Zeman, Marek
14 Zeman, Martin
2 Zeman, Matěj
8 Zeman, Michal
1 Zeman, Mikuláš
4 Zeman, Milan
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