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As a result of the various evolving needs, thermoluminescence dosimetry is constantly under development, with applications intended in environmental and personal radiation monitoring through to the sensing of radiotherapy and radiation processing doses. In radiotherapy dosimetry challenges include small-field profile evaluation, encompassing the fine beams of radiosurgery, evaluations confronting the steep dose gradients of electronic brachytherapy and the high dose rates of FLASH radiotherapy. Current work concerns the thermoluminescent dosimetric properties of commercial low-cost borosilicate glass in the form of thin (sub-mm to a few mm) plates, use being made of microscope cover-slips irradiated using clinical external-beam radiotherapy facilities as well as through use of 60Co gamma irradiators. In using megavoltage photons and MeV electrons, characterization of the dosimetric response has been made for cover-slips of thicknesses up to 4 mm. Reproducibility to within +/5% has been obtained. In particular, for doses up to 10 Gy, the borosilicate cover-slips have been demonstrated to have considerable potential for use in high spatial resolution radiotherapy dosimetry, down to 0.13 mm in present work, with a coefficient of determination in respect of linearity of >0.99 for the thinner cover-slips. Results are also presented for 0.13- and 1.00-mm thick cover slips irradiated to 60Co gamma-ray doses, initially in the range 5- to 25 Gy, subsequently extended to 5 kGy-25 kGy, again providing linear response. The conceptual design of a soil-moisture measurement instrument using a rectangular soil sample and an almost collimated 241Am-9Be source was proposed. Unlike previous studies and in a different simulation approach, the soil moisture was determined using the angular distribution of thermal neutrons using MCNPX2.6 Monte Carlo code, where a cylindrical BF3 proportional counter located at different polar angles was responsible for thermal neutron detection. Both Monte Carlo library least-squares method (MCLLS) and artificial neural networks (ANN) were used to calculate the soil moisture based on BF3 count rates with small relative error, about 2% and 10% maximum relative errors, respectively. Dosimetry properties of nanocrystalline SrSO4Sm powders prepared via a co-participation method, were studied. X-ray diffraction, energy dispersive X-ray spectroscopy and Field emission scanning electron microscopy (FE-SEM) were used to investigate the structure, composition and morphology of nanocrystalline SrSO4Sm powders. The nanocrystalline SrSO4Sm powders had the orthorhombic crystal structure. FE-SEM image showed polygonal structure of particles with an average size of particles 0.2 μm. The thermoluminescence (TL) measurements for different concentration of samarium were done after gamma irradiation. TL glow curves showed the main glow peak at 370 °C. Tamoxifen supplier The maximum intensity of the TL glow curves for SrSO4Sm was obtained with 0.05mol% concentration of Sm. Then, due to its high intensity glow curve, it was selected as the main sample. Furthermore, its dose-response, energy-response, and fading were studied in detail. Nanocrystalline SrSO4Sm(0.05 mol%) powder had a linear dose-response approximately between 10Gy and 3 kGy. It showed energy dependence for low energy photons and its fading was less than 20% after 37 days. The X-ray excited luminescence (XEL), and TL were examined. The kinetic parameters were calculated by using the various TL analysis methods and OriginPro 8 software. The results showed the main TL glow peak obeyed second order kinetics. The aim of the present paper is to develop a novel method for fluorimetric determination of uranium in rock/mineral solutions containing hydrolysable elements such as Nb, Ta, Zr and Ti sequestered by bi-fluoride. These rocks/minerals are decomposed with ammonium bi-fluoride (NH4HF2) and sulfuric acid (H2SO4) mixture. Uranium in such mineral solutions is selectively extracted into ethyl acetate with 2,3-dihydroxynaphthalene at pH 10-12 in the presence of cetyltrimethylammonium bromide, prior to its pellet fluorimetric determination. Optimizations of certain parameters such as the effects of fluoride fluxes, mineral acids, masking agents and diverse ions are discussed in detail. This method is applied for the determination of uranium in synthetic mixtures and a set of in-house reference refractory minerals including certified reference material X1807 with a high degree of accuracy and precision. The results for the refractory minerals using the proposed method are in excellent agreement with results obtained by other standard methods. The novelty of the proposed method is that the decomposition mixture (NH4HF2/H2SO4) inhibits the hydrolysis of hydrolysable elements by formation of their soluble fluoro complexes, and the separation of uranium using the complexing agent 2,3-dihydroxynaphthalene is more eco-friendly compared to existing the conventional solvent extraction system using aluminum nitrate as the salting out agent. The use of high pure industrial crystalline Si wafers as backing materials for PIXE elemental analysis of aqueous liquid samples has been investigated. It can potentially be applied as supporting material of liquid samples owing to its advantages being available at high purity, resistant to ion beam heating effects, unaffected by chemicals, surface easily cleanable, semi-conductor that inhibits local ion beam charging effects, durable, relatively cheap and easily prepared for liquid sample deposition. Sample preparation procedure, deposition homogeneity aspects, experimental conditions and ion beam parameters optimization have been discussed. Comprehensive verification study to perform direct PIXE measurements on reference aqueous liquid sample containing 27 elements, micropipetted on Si wafers has been implemented. A combination of minimum sample preparation procedures and specific experimental conditions applied enables simple and accurate elemental analysis. Elemental concentrations, at about 5-15% absolute accuracy and uncertainties less than 15% for most elements detected, sensitivity curves and detection limits have been determined. Advantages and limitations of using Si wafers in this investigation have been discussed. Comprehensive literature comparison with other backing materials has been reviewed.

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