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Showing 1 to 16 of 16 for “"Polonium"”.
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Polonium-210 radioactivity in Lake Mead fish
Polonium-210, a naturally occurring radioisotope, has been found at high concentrations in marine fish. One publication reports much lower concentration (on the order of 10{dollar}\sp{-1}{dollar}) of {dollar}\sp{210}{dollar}Po in fresh-water fish compared to salt-water, although the visceral organs …
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Alpha-Gamma Directional Correlation in Polonium-211
Made available in DSpace on 2015-05-12T17:12:06Z (GMT). No. of bitstreams: 2 license.txt: 4848 bytes, checksum: 96035ab3f5e1c23cc7138a224ce498bd (MD5) 0020890.PDF: 3853025 bytes, checksum: b8795662aa4c3b10b642063555ca1d0d (MD5) Previous issue date: 1957
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The Kinetics of Neutralization of Polonium-218
… experimental system the neutralization of polonium-218 ions was investigated as a function of the physical and chemical properties of the controlled composition atmosphere. The mobilities of ${\rm Po}\sp+$ and ${\rm PoO}\sbsp{2}{+}$ are determined by combining experimental results with a …
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Study of the Bismuth-209(gamma,negative Pion X Neutrons)polonium-(209-X) and Lead-206 (helium-3, X Neutrons) Polonium-(209-X) Reactions by Detection of Polonium Alpha Activities
Made available in DSpace on 2015-05-12T21:41:40Z (GMT). No. of bitstreams: 2 license.txt: 4848 bytes, checksum: 96035ab3f5e1c23cc7138a224ce498bd (MD5) 6711857.PDF: 5628961 bytes, checksum: 271ce3088186a00d9f9a475ef306f8e4 (MD5) Previous issue date: 1967
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Polonium extraction techniques for a lead-bismuth cooled fast reactor
… were performed to determine the kinetics of polonium hydride and lead-polonide released from molten lead-bismuth to determine the rate response of gaseous polonium chemical species in contact with various argon and hydrogen gas streams. It was determined that the rate release of polonium …
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Investigating the ocean’s biological pump using thorium-235 and polonium-210
Oceans play a critical role in the Earth’s ability to regulate atmospheric carbon dioxide, absorbing approximately one-third of all anthropogenically-emitted CO2. The biological pump is a mechanism which controls oceanic uptake of CO2 and sequestration of carbon into deeper waters. It is a complex …
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Polonium-210 in Freshwater Environments: Analytical Advances, Predictive Modelling, Food Web Transfer and Dose Assessment
Polonium-210 (²¹⁰Po) is a naturally occurring radionuclide of high radiological relevance, yet its occurrence, environmental behaviour and biological transfer in freshwater ecosystems remain poorly characterized. Advances in understanding have been constrained by analytical challenges and by …
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Aufbau eines Experimentes zur Messung der Emissionswahrscheinlichkeit von Bremsstrahlung im alpha-Zerfall von Polonium-210
Die Emissionswahrscheinlichkeit von Bremsstrahlung kann in den meisten Fällen sehr gut semi-klassisch beschrieben werden. Beim Alpha-Zerfall jedoch tunnelt das Alpha-Teilchen durch die Coulomb-Barriere des Kernes, ein Prozess, der nur quantenmechanisch begriffen werden kann. Hierbei stellt sich die …
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Study of the Bi209 (gamma,pi-xn) Po209-x and Pb206 (He3,xn) Po209-x reactions by detection of polonium alpha activities
The cross sections for Bi 209{gamma, pi-xn ) Po209-x were measured for x = 0-3, 5, and 7 and used to estimate the total (gamma, pi-) cross section. Total (gamma, pi-) cross sections have not previously been measured for a complex nucleus. At bremsstrahlung energies of 200,220, and 250 MeV, the …
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Studies of alpha-radioactivity in the marine environment
… thorium series nuclides and "excess" unsupported polonium-210 were determined by using the "thorium pairs" technique and by studying the variation of the total alpha count-rate with time. This is considered in Chapter 2. The 'second phase of the investigation was to investigate the alpha-spectrum …
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High-Throughput Ab Initio Phase Diagram Prediction
… the phase diagrams of the heavy metals lead and polonium. In the process, insight is gained into the best strategies for developing EDDPs, and their behaviour in dynamical calculations. The effects of spin-orbit coupling on structure and melting point are analysed. I produce the first-ever …
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Conceptual design of a lead-bismuth cooled fast reactor with in-vessel direct-contact steam generation
… of the turbine and 3) the release of radioactive polonium (a product of coolant activation) to the steam. Modeling of the multi-phase phenomena occurring in the chimney confirmed the effectiveness of the direct contact heat transfer mode within a well-defined design envelope for the reactor power, …
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Cavity Ringdown Spectroscopy in Nitrogen/Oxygen Mixtures in the Presence of Alpha Radiation
… in nitrogen-oxygen mixtures while the Polonium 210 alpha sources were cycled between being shielded and exposed.</p> <p>The beginning of this thesis will provide brief reviews of ionizing radiation and ozone formation, along with explanations of Cavity Enhanced Absorption Spectroscopy …
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Realizing a design for a cloud chamber cooled by thermoelectric modules
… region was observed using three materials: Polonium-210, Lead-2 10, and Strontium-90. The cloud chamber can be improved and further work is discussed.
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Deportment of radionuclides in copper concentrate from Olympic Dam
The Olympic copper-gold province of South Australia is home to the world’s largest uranium resource, representing at least 23% of the known global uranium budget. The primary commodity produced is copper, with secondary Au, Ag, and U (as U₃O₈) also recoverable in economic quantities. Processing the …