Journal of Nuclear Physics, Material Sciences, Radiation and Applications最新文献_第5页

Radon Dose Determination and Radiological Risk in Some Mexican Caves with CR-39 Detectors CR-39探测仪测定墨西哥洞穴氡剂量及辐射风险

Journal of Nuclear Physics, Material Sciences, Radiation and Applications Pub Date : 2021-02-10 DOI: 10.15415/JNP.2021.82022

A. Chavarria, J. Golzarri, G. Espinosa

{"title":"Radon Dose Determination and Radiological Risk in Some Mexican Caves with CR-39 Detectors","authors":"A. Chavarria, J. Golzarri, G. Espinosa","doi":"10.15415/JNP.2021.82022","DOIUrl":"https://doi.org/10.15415/JNP.2021.82022","url":null,"abstract":"Radon (222Rn) is a radioactive gas, from the 238U decay chain, that contributes in large part of the natural radiation dose to which humans are exposed. Radon is the second cause of lung cancer after tobacco. The US-EPA considers a concentration of 148 Bq/m3 for homes and 400 Bq/m3 for workplaces as the reference level. Caves are closed spaces where 222Rn, which emanates from the surrounding minerals and rocks, can accumulate and reaches large concentrations that can represent a health risk for the guides, speleologists and visitors who spend time in these spaces. This work uses the previously recorded radon concentrations in 8 caves in Mexico and calculates the average dose range and the average annual dose for each of them with the “Wise” public domain program (http://www.wise-uranium.org/rdcrn.html) to determine the level of radiological risk with 2,000 1,000 and 500 working hours per year. Karmidas cave had the highest average 222Rn concentration with 27,633.3 Bq/m3 and for 2,000 working hours per year an average annual dose rate of 347.1 mSv/y. Los Riscos cave had the lowest average concentration with 384.7 Bq/m3 and for 2,000 working hours per year an average annual dose rate of 4.832 mSv/y. These results show that all the caves studied present values,with 2,000 working hours per year, that exceed 3 mSv/y for workplaces and must be considered by the people who work in these places. A casual tourist visiting the caves does not present any radiological risk, while guides and speleologists should consider it.","PeriodicalId":16534,"journal":{"name":"Journal of Nuclear Physics, Material Sciences, Radiation and Applications","volume":"15 1","pages":"169-175"},"PeriodicalIF":0.0,"publicationDate":"2021-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87498703","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Determination of 234U and 238U Activities in Soil by Liquid Scintillation and High-Resolution Alpha Spectrometry 液体闪烁-高分辨率α光谱法测定土壤中234U和238U的活性

Journal of Nuclear Physics, Material Sciences, Radiation and Applications Pub Date : 2021-02-10 DOI: 10.15415/JNP.2021.82014

Montero-Cabrera María Elena, Caraveo-Castro Carmen del Rocío, Méndez-García Carmen Grisel, Mendieta-Mendoza Aurora, Renteria-Villalobos Marusia, Cabral-Lares Rocío Magaly

引用次数: 0

Receptor Binding Domain (RBD) Structural Susceptibility in the SARS-CoV-2 Virus Spike Protein Exposed to a Pulsed Electric Field 脉冲电场下SARS-CoV-2病毒刺突蛋白受体结合域(RBD)结构敏感性研究

Journal of Nuclear Physics, Material Sciences, Radiation and Applications Pub Date : 2021-02-10 DOI: 10.15415/JNP.2021.82023

D. Osorio-González, V. J. Muñiz-Orozco, C. Gonzalez, M. Fuentes-Acosta, J. Mulia-Rodríguez, L. A. Mandujano-Rosas

{"title":"Receptor Binding Domain (RBD) Structural Susceptibility in the SARS-CoV-2 Virus Spike Protein Exposed to a Pulsed Electric Field","authors":"D. Osorio-González, V. J. Muñiz-Orozco, C. Gonzalez, M. Fuentes-Acosta, J. Mulia-Rodríguez, L. A. Mandujano-Rosas","doi":"10.15415/JNP.2021.82023","DOIUrl":"https://doi.org/10.15415/JNP.2021.82023","url":null,"abstract":"Received: September 28, 2020 Accepted: January 27, 2021 Published Online: February 10, 2021 SARS-CoV-2 is responsible for causing the Coronavirus disease 2019 (COVID-19) pandemic, which has so far infected more than thirty million people and caused almost a million deaths. For this reason, it has been a priority to stop the transmission of the outbreak through preventive measures, such as surface disinfection, and to establish bases for the design of an effective disinfection technique without chemical components. In this study, we performed in silico analysis to identify the conformational alterations of the SARS-CoV-2 Spike Receptor Binding Domain (RBD) caused by the effect of a pulsed electric field at two different intensities. We found that both stimuli, especially the one with the highest angular frequency and amplitude, modified the electrical charge distribution in the RBD surface and the number of hydrogen bonds. Moreover, the secondary structure was significantly affected, with a decrease of the structured regions, particularly the regions with residues involved in recognizing and interacting with the receptor ACE2. Since many regions suffered conformational changes, we calculated RMSF and ΔRMSF to identify the regions and residues with larger fluctuations and higher flexibility. We found that regions conformed by 353-372, 453-464, and 470-490 amino acid residues fluctuate the most, where the first is considered a therapeutic target, and the last has already been characterized for its flexibility. Our results indicate that a pulsed electric field can cause loss of stability in the Spike-RBD, and we were able to identify the vulnerable sites to be used as a starting point for the development of viral inhibition or inactivation mechanisms.","PeriodicalId":16534,"journal":{"name":"Journal of Nuclear Physics, Material Sciences, Radiation and Applications","volume":"58 1","pages":"177-182"},"PeriodicalIF":0.0,"publicationDate":"2021-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84865471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Superficial Surface Treatment using Atmospheric Plasma on Recycled Nylon 6,6 大气等离子体对再生尼龙6,6的表面处理

Journal of Nuclear Physics, Material Sciences, Radiation and Applications Pub Date : 2021-02-10 DOI: 10.15415/JNP.2021.82025

M. Rodríguez, E. Vázquez‐Vélez, H. Martinez, A. Torres

引用次数: 1

Simultaneous Grafting of Poly(Acrylic Acid) and Poly(Ethylene Glycol) onto Chitosan using Gamma Radiation: Polymer Networks for Removal of Textile Dyes 聚丙烯酸和聚乙二醇在壳聚糖上同时接枝的伽马辐射-聚合物网络脱除纺织染料

Journal of Nuclear Physics, Material Sciences, Radiation and Applications Pub Date : 2021-02-10 DOI: 10.15415/JNP.2021.82017

M. P. Carreón-Castro, M. Caldera-Villalobos, B. Leal-Acevedo, A. Herrera-González

{"title":"Simultaneous Grafting of Poly(Acrylic Acid) and Poly(Ethylene Glycol) onto Chitosan using Gamma Radiation: Polymer Networks for Removal of Textile Dyes","authors":"M. P. Carreón-Castro, M. Caldera-Villalobos, B. Leal-Acevedo, A. Herrera-González","doi":"10.15415/JNP.2021.82017","DOIUrl":"https://doi.org/10.15415/JNP.2021.82017","url":null,"abstract":"Chitosan is a bio-based polyelectrolyte with high potential for wastewater treatment. Chitosan can remove anionic dyes by adsorption but it has low performance in the removal of cationic dyes. In this work, we report the synthesis of chitosan-based graft-copolymers using gamma radiation. Acrylic acid and poly(ethylene glycol) were grafted successfully onto chitosan applying a radiation dose of 12 kGy at a dose rate of 8 kGyh-1. The grafted-copolymers have improved adsorptive properties for the removal of basic dyes reaching a maximum adsorption capacity higher than 300 mgg-1. The Lanmguir’s isotherm model described satisfactorily the interaction between the grafted copolymers and basic dyes. Freundlich’s isotherm model described the adsorption of anionic dye acid orange 52. The grafted copolymers removed successfully textile dyes from wastewater of the dyeing process. The best results were obtained in the removal of direct and basic dyes. Further, poly(ethylene glycol) grafted on the copolymer conferred better swelling behavior making easy the separation of the adsorbent after dye removal. The results showed that the adsorbent materials synthesized by radiochemical graftcopolymerization are more efficient than the beads, composite materials, and blends of chitosan.","PeriodicalId":16534,"journal":{"name":"Journal of Nuclear Physics, Material Sciences, Radiation and Applications","volume":"17 1","pages":"135-142"},"PeriodicalIF":0.0,"publicationDate":"2021-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87443416","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Wear Behavior of a Ni/Co Bilayer Coating by Physical Vapor Deposition on AISI 1045 Steel AISI 1045钢物理气相沉积Ni/Co双层涂层的磨损性能

Journal of Nuclear Physics, Material Sciences, Radiation and Applications Pub Date : 2021-02-10 DOI: 10.15415/JNP.2021.82027

S. Rodil, B. Campillo, I. Domínguez, J. González-Rodríguez, H. Martínez

引用次数: 2

Simulation of Dose Estimations from Solar Protons: A PMMA-Bi2O3 Shielding Model for Space Exploration 太阳质子剂量估算的模拟:用于空间探索的PMMA-Bi2O3屏蔽模型

Journal of Nuclear Physics, Material Sciences, Radiation and Applications Pub Date : 2021-02-10 DOI: 10.15415/JNP.2021.82020

L. Sajo-Bohus, J. A. López, M. Castro-colin

{"title":"Simulation of Dose Estimations from Solar Protons: A PMMA-Bi2O3 Shielding Model for Space Exploration","authors":"L. Sajo-Bohus, J. A. López, M. Castro-colin","doi":"10.15415/JNP.2021.82020","DOIUrl":"https://doi.org/10.15415/JNP.2021.82020","url":null,"abstract":"Adverse effects of long-term exposure to galactic cosmic radiation (GCR) pose a non negligible obstacle for future space exploration programs; the high-LET-particle-rich environment has an adverse effect on human health. Concomitant to GCR we have as well solar particle radiation. Long term space exploration will rely on adequate and highly efficient shielding materials that will reduce exposure of both biosystems and electronic equipment to GCR and solar particles. The shield must attenuate efficiently heavy GCR ions, by breaking them up into less-damaging fragments and secondary radiation: biologically damaging energetic neutrons and highly charged and energetic HZE- particles. An approach to this problem is the development of shielding compounds. Shielding materials should address the conditions of different aspects of a given mission, e.g. time duration and travel path. The Monte Carlo method (GEANT4) is here employed to estimate the effects of a shielding material based on the recently developed Bi2O3-based compound (Cao et al., 2020). In the present study GEANT4 code is used to make estimations of attenuation of solar protons. The objective is to provide some insight about the effect of the new composite shield that has an intrinsic capability for dose reduction.","PeriodicalId":16534,"journal":{"name":"Journal of Nuclear Physics, Material Sciences, Radiation and Applications","volume":"19 1","pages":"155-160"},"PeriodicalIF":0.0,"publicationDate":"2021-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86687346","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Changes of the Neutron Flux of the Nuclear Reactor Triga Mark III Since the Conversion from High to Low 235U Enrichment 高铀浓缩到低铀浓缩以来Triga Mark III核反应堆中子通量的变化

Journal of Nuclear Physics, Material Sciences, Radiation and Applications Pub Date : 2021-02-10 DOI: 10.15415/JNP.2021.82019

C. Vázquez-López, O. D. Ángel-Gómez, R. Raya-Arredondo, S. Cruz-Galindo, J. I. Golzarri-Moreno, Guillermo Espinosa

引用次数: 1

Structural Shielding Design of CT Facility using Monte Carlo Simulation 基于蒙特卡罗模拟的CT设备结构屏蔽设计

Journal of Nuclear Physics, Material Sciences, Radiation and Applications Pub Date : 2021-02-10 DOI: 10.15415/JNP.2021.82018

A. Yadav, Basilia Quispe Huillcara, Pablo Víctor Cerón Ramírez, M. S. Aquino, Miguel Ángel Vallejo Hernández

{"title":"Structural Shielding Design of CT Facility using Monte Carlo Simulation","authors":"A. Yadav, Basilia Quispe Huillcara, Pablo Víctor Cerón Ramírez, M. S. Aquino, Miguel Ángel Vallejo Hernández","doi":"10.15415/JNP.2021.82018","DOIUrl":"https://doi.org/10.15415/JNP.2021.82018","url":null,"abstract":"Radiation application in medicine offers extraordinary benefits. But radiation is like a double-edged sword, it has both benefits and associated risks on the community in contact. To justify the safety of workers and members of the public, regulated use of radiation is assessed by the radiation protection protocols. The aim of this study is to design a Computed Tomography (CT) facility with a simplified model of CT scanner, whose shielding follows the guidelines of National Council on Radiation Protection and Measurements (NCRP) Report No. 147. To design the study model, Monte Carlo (MC) radiation transport code in MCNPX 2.6.0 was used for the simulation. Furthermore, MCNPX was used to measure the photon flux in a vicinity or the detector cell. To validate the functioning of the X-ray tube, the experimental results were compared with the X-ray Transition Energies Database of National Institute of Standards and Technology, U.S. Department of Commerce. The results obtained were within 0.60% of relative error. To confirm the functioning of shielding design, radiation protection quantity, air kerma was measured at several points outside, and inside of the CT room and they were under the radiation dose recommended by NCRP, which demonstrates that the shielding design wassuccessful in blocking the radiation. The study can be used for an easy evaluation of any CT room within the framework of the model of the study.","PeriodicalId":16534,"journal":{"name":"Journal of Nuclear Physics, Material Sciences, Radiation and Applications","volume":"2013 1","pages":"143-147"},"PeriodicalIF":0.0,"publicationDate":"2021-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73971251","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

GEANT4 Study of Proton–Body Interactions 质子-体相互作用的研究

Journal of Nuclear Physics, Material Sciences, Radiation and Applications Pub Date : 2021-02-10 DOI: 10.15415/JNP.2021.82015

J. A. López, S. González, O. Rodriguez, J. Holmes, R. Alarcon

{"title":"GEANT4 Study of Proton–Body Interactions","authors":"J. A. López, S. González, O. Rodriguez, J. Holmes, R. Alarcon","doi":"10.15415/JNP.2021.82015","DOIUrl":"https://doi.org/10.15415/JNP.2021.82015","url":null,"abstract":"Received: September 18, 2020 Accepted: January 09, 2021 Published Online: February 10, 2021 Proton therapy uses a beam of protons to destroy cancer cells. A problem of the method is the determination of what part of the body the protons are hitting during the irradiation. In a previous study we determine that by capturing the gamma rays produced during the irradiation one can determine the location of the proton-body interaction, in this work we investigate if by examining the gamma rays produced it is possible to determine the body part that produced the gamma rays by the proton collision. This study uses GEANT4 computer simulations of interactions of proton-tissue, protonbrain, proton-bone, etc., which produce gamma rays, to determine the characteristics of the gamma rays produced. We then analyze the characteristics of the gamma rays to find signatures that could be used to determine the source of the rays. In particular, we study the distribution of gamma ray energies, their full-width half-maximum, energy resolution, maximum height, and total number of counts. This study concludes that it is possible to use the gamma ray spectra to determine what body part produced it.","PeriodicalId":16534,"journal":{"name":"Journal of Nuclear Physics, Material Sciences, Radiation and Applications","volume":"8 1","pages":"121-127"},"PeriodicalIF":0.0,"publicationDate":"2021-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81544393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1