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Abstract  

127I Mössbauer spectra for the phenyliodonium ylides were measured at 20 K. The valence electron populations (Ns, Nx-z) and the charge number (ZI) for iodine atom are estimated from the Mössbauer parameters. The obtained populations were very close to those of diphenyliodonium chloride having two I-C primary bonds. To examine the possibility of some double bond character, the electron populations for the case of Nz = 1.90 are estimated. In this case, the ZI values become larger as 1.2-1.3, and these values were unreasonably large because the values are close to those of PhICl2, PhI(OAc)2 having electron withdrawing ligands. Thereby, 127I Mössbauer parameters suggest little double bond character for phenyliodonium ylides.

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Abstract  

A simple method employing neutron activation and radiochemical separation was developed for simultaneous determination of the concentrations of232Th(Th) and238U(U) in biological materials. Using this method, it is possible to detect 0.05 and 0.2 ng of Th and U, respectively, in the samples. This method was applied to determine the daily dietary intake of these two nuclides by the population living in the high background areas of India (Monazite area), where the soil contains very high levels of these two nuclides. The comparison of the daily intakes by the population living in high and normal background areas showed significantly higher intake of these two nuclides by the high background population.

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Abstract  

Competing groups in a population will be integrated or segregated depending on their contest strategies. In this work a population of a fixed proportion of hawks and doves is supposed to be able to employ two different contest strategies, one more competitive than the other one. Energies are derived for populations employing these strategies and these energies depend on the availability of the resource for which hawks and doves compete. The energy for the less competitive strategy is lower than the other one when the resource is abundant. In that case hawks and doves can be in cohabitation in all proportions. If, however, the resource is scarce, the energy of the more competitive strategy is lower than the other one. In that case complete segregation of hawks and doves into colonies will result. The situation is akin to the phase pressure diagram of a binary solution with eutectic point, miscibility gap in the liquid phase and complete miscibility in the vapour phase.

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Abstract  

Statistical tests were performed on the -spectrometry measurement data obtained during the last decade for the natural radionuclides40K,226Ra and232Th, in water samples collected from the Danube River, the Sava River and its tributaries, ground waters and artificial lakes. The lognormal radiopotassium distribution indicates a single statistical population. The presence of break points in the frequency distribution plots indicates that data for226Ra and232Th do not come from a single statistical population. The annual iongestion of40K,226Ra and232Th was calculated and expressed in Bq y–1.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: T. Martinez, J. Lartigue, P. Avila-Perez, G. Zarazua, M. Navarrete, S. Tejeda, and A. Ramírez

Abstract  

Trace elements were determined by TXRF in whole blood samples in a randomly non-occupational exposed population living in the Metropolitan Zone of the Mexico Valley (MZMV). Arithmetic and geometric means of S, Ca, Cu, Zn, Rb and Pb concentrations, were on the reported range values for non-occupational population in other countries, while those of K and Br were higher, possibly due to dietary habits and geographical or environmental factors. The noticeable decline in blood lead level (91%) should be positively perceived. As a part of the Quality Control Program, a certified IAEA-A13 was tested.

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Abstract  

This paper estimates the body content and excretion levels of Pu from the combined intake from the global and Chernobyl fallout. The approach developed allows to estimate the contributions from each component. This approach is necessary for estimating the average and collective doses to the population of different regions or settlements. Verifications of this approach have been made using autopsy data (the early stage of the accident, Kiev residents, the late stage inhabitants of the Ovruch region) which are in good agreement. Assessment of the dose from transuranics to the population of the Ukraine required using bioassay data. This was achieved by measuring the urinary excretion of Pu.

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Abstract  

The training process and training programs in both commercial nuclear plants and Department of Energy (DOE) nuclear facilities have improved significantly in the years following the Three-Mile Island (TMI) accident. This article describes some of these changes, including the reasons behind the change, the affected population, the training accreditation process and performance-based training, and the benefits of the changes.

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Abstract  

Eleven trace elements were determined in the hair of Chuquicamata copper mine workers and of children living in camp by means of neutron activation analysis. Comparative studies demonstrated that concentrations of certain elements were greater than those corresponding to the nonexposed populations. Arsenic exceeded the normal limit considered for this element by health organizations.

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Abstract  

The paper deals with modeling of -radiation fields produced by natural terrestrial radionuclides in construction materials of houses. Isodoses computed in planes crossing a rectangular room with specified thickness of walls as well as the concentration of radionuclides in building materials enable one to estimate health risks of the population dwelling in such a room.

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Abstract  

The occurrence of anomalous enhancements of U-isotope activities in the surrounding environment of a phosphate fertilizer factory complex at the southwest of Spain has been established. It seems that significant amounts of U, released by such industries, are being accumulated in the environment, which may substantially contribute to the collective radiation dose received by the local population.

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