A short review is given for the determination of gross alpha activity ill urine;detailed information is collected including urine mineralization,separation of alpha emitters and source preparation.
The response of a silicon alpha detector to beta particles, electrons and photons was investigated using measurements and Monte Carlo simulations. This information is of relevance for in situ alpha spectrometry from d...The response of a silicon alpha detector to beta particles, electrons and photons was investigated using measurements and Monte Carlo simulations. This information is of relevance for in situ alpha spectrometry from different surfaces at ambient air pressure. According to the simulations, photon detection efficiencies were more than two orders of magnitude smaller than those of electrons. Photons generate signals mainly by Compton electrons. Counts originating from beta particles, electrons and photons were usually below 1 MeV in energy and no clear peaks could be identified from the measured spectra. Unequivocal identification of radionuclides emitting beta particles, electrons and photons is not possible when a mixture of different radionuclides is present in the source. However, radionuclide classification according to their emission energies appears to be possible. Surface contamination measurements will benefit from this capability.展开更多
Distribution of Cu, Zn, Pb, Cr, Ni, Mn concentrations and the activity of polonium-210 in the surrounding area of a phosphate fertilizer industry located on the eastern coast of the Mediterranean Sea has been determin...Distribution of Cu, Zn, Pb, Cr, Ni, Mn concentrations and the activity of polonium-210 in the surrounding area of a phosphate fertilizer industry located on the eastern coast of the Mediterranean Sea has been determined. Nineteen sampling sites were distributed around the industrial zone on a surface area of about 100,000 m^2. Atomic absorption spectroscopy and Alpha spectroscopy were used to quantify the heavy elements and polonium-210, respectively. Investigation on a particle scale was conducted by TEM and SEM coupled to EDX and X-ray cartography to determine the nature of heavy elements carriers and their distribution. Heavy elements were mainly concentrated inside the particle size fraction 〈 50 μm. Their levels decreased with distance increasing from the industry. According to the reference soil, enrichment factors were about 10, 15, 32 and 100 times for Zn, Pb, Cu, and Cr, respectively inside the particle size fraction 〈 50 μm on the closest sites to the industry. The main contaminant sources were transport and storage of row materials and the free release of phosphogypsum waste. Heavy elements were entrapped inside agglomerates of sulfates, phosphates and iron oxihydroxides in a diffused shape. Polonium-210 with an enrichment factor of about 56, showed the same behavior of the spatial distribution of the trace elements.展开更多
文摘A short review is given for the determination of gross alpha activity ill urine;detailed information is collected including urine mineralization,separation of alpha emitters and source preparation.
文摘The response of a silicon alpha detector to beta particles, electrons and photons was investigated using measurements and Monte Carlo simulations. This information is of relevance for in situ alpha spectrometry from different surfaces at ambient air pressure. According to the simulations, photon detection efficiencies were more than two orders of magnitude smaller than those of electrons. Photons generate signals mainly by Compton electrons. Counts originating from beta particles, electrons and photons were usually below 1 MeV in energy and no clear peaks could be identified from the measured spectra. Unequivocal identification of radionuclides emitting beta particles, electrons and photons is not possible when a mixture of different radionuclides is present in the source. However, radionuclide classification according to their emission energies appears to be possible. Surface contamination measurements will benefit from this capability.
基金supported by the research grants program of the Lebanese Council for Scientific Research
文摘Distribution of Cu, Zn, Pb, Cr, Ni, Mn concentrations and the activity of polonium-210 in the surrounding area of a phosphate fertilizer industry located on the eastern coast of the Mediterranean Sea has been determined. Nineteen sampling sites were distributed around the industrial zone on a surface area of about 100,000 m^2. Atomic absorption spectroscopy and Alpha spectroscopy were used to quantify the heavy elements and polonium-210, respectively. Investigation on a particle scale was conducted by TEM and SEM coupled to EDX and X-ray cartography to determine the nature of heavy elements carriers and their distribution. Heavy elements were mainly concentrated inside the particle size fraction 〈 50 μm. Their levels decreased with distance increasing from the industry. According to the reference soil, enrichment factors were about 10, 15, 32 and 100 times for Zn, Pb, Cu, and Cr, respectively inside the particle size fraction 〈 50 μm on the closest sites to the industry. The main contaminant sources were transport and storage of row materials and the free release of phosphogypsum waste. Heavy elements were entrapped inside agglomerates of sulfates, phosphates and iron oxihydroxides in a diffused shape. Polonium-210 with an enrichment factor of about 56, showed the same behavior of the spatial distribution of the trace elements.
