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Results in Journal Journal of Nuclear Physics, Material Sciences, Radiation and Applications: 181

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Amr Abdelhady
Journal of Nuclear Physics, Material Sciences, Radiation and Applications, Volume 8, pp 7-10; doi:10.15415/jnp.2020.81002

Abstract:
This study aims to evaluate the radiation dose rate distribution inside temporary spent fuel open-pool storage. The storage pool is connected to the main pool via transfer channel to facilitate transporting the spent fuel under water that avoiding radiation dose rising in the working area in the reactor. The storage pool was prepared to store 800 spent fuel elements that considering the maximum capacity of storage. The spent fuel elements in the storage pool have different decay times depending on the times of extraction from the core. Assuming conservatively, that the spent fuels of the 5-years decay time would be stored in the lower rack and the spent fuels, of decay time ranged between 10 days and 5 years, would be stored in the upper rack. The dose rate was profiled in the region above the upper rack using SCALE/MAVRIC code applying adjoint flux calculation as a variance reduction technique. The results show that the dose rate values in the region above the pool surface would be lower than the permissible limits.
Sardar Muhammad Shauddin
Journal of Nuclear Physics, Material Sciences, Radiation and Applications, Volume 8, pp 1-6; doi:10.15415/jnp.2020.81001

Abstract:
Due to cost effective and simplicity homogeneous reactors have been widely used for experimental and research purposes. Parameters which are difficult to get from a heterogeneous reactor system can be easily obtained from a homogeneous reactor system and can be applied in the heterogeneous reactor system if the major parametric differences are known. In this study, homogenization effects of VVER (Water Water Energetic Reactor)-1000 fuel assembly on neutronic parameters have been analyzed with the universal probabilistic code MCNP (Monte Carlo N-Particle). The infinite multiplication factor (k∞) has been calculated for the reconfigured heterogeneous and homogenous fuel assembly models with 2 w/o U-235 enriched fuel at room temperature. Effect of mixing soluble boron into the moderator/coolant (H2O) has been investigated for both models. Direct and fission detected thermal to higher energy neutron ratio also has been investigated. Relative power distributions of both models have been calculated at critical and supercritical states. Burnup calculations for both the reconfigured cores have been carried out up to 5 years of operation. Effective delayed neutron fraction (βeff) and prompt removal lifetime (ℓ) also have been evaluated. All the results show significant differences between the two systems except the average relative power.
Sciprofile linkSatya Seshavatharam U.V, Lakshminarayana S
Journal of Nuclear Physics, Material Sciences, Radiation and Applications, Volume 7, pp 43-51; doi:10.15415/jnp.2019.71005

Abstract:
To understand the mystery of final unification, in our earlier publications, we proposed two bold concepts: 1) There exist three atomic gravitational constants associated with electroweak, strong and electromagnetic interactions. 2) There exists a strong elementary charge in such a way that its squared ratio with normal elementary charge is close to reciprocal of the strong coupling constant. In this paper we propose that, ℏc can be considered as a compound physical constant associated with proton mass, electron mass and the three atomic gravitational constants. With these ideas, an attempt is made to understand nuclear stability and binding energy. In this new approach, with reference to our earlier introduced coefficients k = 0.00642 and f = 0.00189, nuclear binding energy can be fitted with four simple terms having one unique energy coefficient. The two coefficients can be addressed with powers of the strong coupling constant. Classifying nucleons as ‘free nucleons’ and ‘active nucleons’, nuclear binding energy and stability can be understood. Starting from , number of isotopes seems to increase from 2 to 16 at and then decreases to 1 at For Z >= 84, lower stability seems to be, Alower=(2.5 to 2.531)Z.
Journal of Nuclear Physics, Material Sciences, Radiation and Applications, Volume 7, pp 71-76; doi:10.15415/jnp.2020.72007

Abstract:
The emission of characteristic X-rays induced by proton impact is a phenomenon known since the first half of the 20th century. Its more widely known application is the analytical technique Particle Induced X-ray Emission (PIXE). Several models have been developed to calculate, first, ionization cross sections and then the subsequent X-ray production cross sections. However, to carry out the comparisons of these predictions with experimental data it is necessary to use atomic parameters databases (fluorescence yields, Coster-Kronig transition probabilities, emission rates) that also have experimental uncertainties. In this work it is demonstrated how these values do not allow to decide which model describes more accurately the cross sections, due to a final “theoretical uncertainty” obtained through the propagation of the original uncertainties.
T. A. Valencia-Pérez, J. M. Hernández-López, E. Moreno-Barbosa, B. De Celis-Alonso
Journal of Nuclear Physics, Material Sciences, Radiation and Applications, Volume 7, pp 165-171; doi:10.15415/jnp.2020.72021

Abstract:
In medicine, the acquisition process in Computed Tomography Images (CT) is obtained by a reconstruction algorithm. The classical method for image reconstruction is the Filtered Back Projection (FBP). This method is fast and simple but does not use any statistical information about the measurements. The appearance of artifacts and its low spatial resolution in reconstructed images must be considered. Furthermore, the FBP requires of optimal conditions of the projections and complete sets of data. In this paper a methodology to accelerate acquisition process for CT based on the Maximum Likelihood Estimation Method (MLEM) algorithm is presented. This statistical iterative reconstruction algorithm uses a GPU Programming Paradigms and was compared with sequential algorithms in which the reconstruction time was reduced by up to 3 orders of magnitude while preserving image quality. Furthermore, they showed a good performance when compared with reconstruction methods provided by commercial software. The system, which would consist exclusively of a commercial laptop and GPU could be used as a fast, portable, simple and cheap image reconstruction platform in the future.
K. De Los Ríos, C. Méndez-García, Sciprofile linkLuis Acosta, R. García-Martínez, M. A. Martínez-Carrillo, M. E. Ortiz
Journal of Nuclear Physics, Material Sciences, Radiation and Applications, Volume 7, pp 145-151; doi:10.15415/jnp.2020.72018

Abstract:
The meteoric cosmogenic beryllium has been used as an essential geophysical tracer in the analysis of atmospheric flows and erosion soils since 1960. The first measurements Be-7 and Be-10 concentrations in rainwater from Mexico, have been carried out by using gamma decay spectroscopy and AMS techniques, respectively for each isotope. With this it was possible to report a preliminar value for the Be-10/Be-7 isotopic ratio in such environmental samples. The present work described preliminary results related to rainwater collected at mountain and metropolitan areas. Results are compared with predictions and previous measurements for both radioisotopes, observing a very sensible behavior particularly for the case of Be-7 activities.
Sciprofile linkE. Islas-Ortiz, E. O. Reyes-Salas, A. Negrón-Mendoza, A. L. Meléndez-López, G. Reyes-García, J. A. Cruz- Castañeda, E. Madrigal-Lagunas
Journal of Nuclear Physics, Material Sciences, Radiation and Applications, Volume 7, pp 103-107; doi:10.15415/jnp.2020.72012

Abstract:
In this study, remnants concentrations of curcumin in Curcuma longa (organic turmeric powder) were determined after it was exposed to irradiation doses of 1, 2 and 3 kGy. Curcumin analysis was performed using the analyte-sensitive impulse differential polarography technique (LOD: 0.621 ppm and LOQ: 2.130 ppm). The results obtained showed a decreasing concentration of curcumin as a function of the irradiation dose. This reduction is low in terms of affecting the product’s quality with respect to its concentration.
Laura Patricia Cruz-Cruz, Sciprofile linkA. Negrón-Mendoza, Alejandro Heredia-Barbero
Journal of Nuclear Physics, Material Sciences, Radiation and Applications, Volume 7, pp 83-87; doi:10.15415/jnp.2020.72009

Abstract:
The stability of biologically important molecules, such as amino acids, being subjected to highradiation fields is relevant for chemical evolution studies. Bodies of water were very important in the primitive Earth. In these bodies, the presence of dissolved salts, together with organic molecules, could influence the behavior of the systems in prebiotic environments.The objective of this work is to examine the influence of sodium chloride on the stability of the amino acid glycine when subjected to high radiation doses. The analysis of the irradiated samples was followed by HPLC coupled with a UV-VIS detector. The results show that glycine in aqueous solutions (without oxygen) decomposed around 90% at a dose of 91 kGy. In the presence of salts, up to 80% of the amino acid was recovered at the same dose. Laboratory simulations demonstrate a protective role for sodium chloride (specifically the chloride ion) to glycine against an external source of ionizing radiation.
A. H. Ramírez, O. Talavera, S. Souto, J. I. Golzarri, G. Espinosa
Journal of Nuclear Physics, Material Sciences, Radiation and Applications, Volume 7, pp 203-207; doi:10.15415/jnp.2020.72026

Abstract:
In this work the determination of radon gas (222Rn) and the characterization of chemical elements in drinking water of the city Taxco was carried out. Ingesting or inhaling a small number of radionuclides, as well as water of poor chemical quality, can become a potential public health problem. We are collecting 8 samples of water from a spring, physicochemical parameters were measured in field on different days of the dry season. Measurements of 222Rn were performed in the laboratory with an AlphaGUARD equipment. The chemical quality was analyzed in laboratory too by means of mayor and minor ions, by volumetry and colorimetry. The sodium was determined by Flama Atomic Absorption Spectroscopy (FAAS). Trace elements were analyzed by were determined by Atomic Emission Spectroscopy with Plasma Coupled by Induction (ICP-AES). The concentrations of 222Rn present an average of 22.06 ± 2.52 BqL-1. The results obtained from the main ions and field parameters show a type of diluted sodium-calcium-bicarbonate water. The trace elements present are very small and not exceed the limit of quantification. Radon gas is produced by the igneous rock that is the top of the stratigraphic column, of the hydric recharge. Rainwater when descending through the fractures is impregnated with 222Rn gas and accumulated in the underlying rock that has sufficient porosity to accumulate water and gas in the Chacualco´s spring.
C. Peña-Negrete, M.A. Fuentes-Acosta, J. Mulia, L.A. Mandujano-Rosas, Sciprofile linkD. Osorio-González
Journal of Nuclear Physics, Material Sciences, Radiation and Applications, Volume 7, pp 189-194; doi:10.15415/jnp.2020.72024

Abstract:
Rotavirus diarrhea is an infectious intestinal disease that causes about 215 thousand deaths annually in infants under five years old. This virus is formed by three layers of concentric proteins that envelop its genome, from which VP6 structural protein is the most conserved among rotavirus serotypes and an excellent vaccine candidate. Recent studies have shown that structural proteins are susceptible to losing their biological function when their conformation is modified by moderate temperature increments, and in the case of VP6, its antigen efficiency decreases. We performed an in silicoanalysis to identify the structural variations in the epitopes 301-315, 357-366, and 376-384 of the rotavirus VP6 protein -in a hydrated medium- when the temperature is increased from 310 K to 322 K. In the latter state, we applied an electric field equivalent to a low energy laser pulse and calculated the fluctuations per amino acid residue. We identified that the region 301-315 has greater flexibility and density of negative electrical charge; nevertheless, at 322 K it experiences a sudden change of secondary structure that could decrease its efficiency as an antigenic determinant. The applied electric field induces electrical neutrality in the region 357-366, whereas in 376-384 inverts the charge, implying that temperature changes in the range 310 K-322 K are a factor that promotes thermoelectric effects in the VP6 protein epitopes in the region 300-396.
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