核科学与技术国际期刊(英文)最新文献

{"title":"Establishing a Relationship between Coal Quality and the Enrichment of Radionuclides in Coal Combustion Residues","authors":"U. A. Q. Ahmed, A. Joubert","doi":"10.4236/WJNST.2019.93008","DOIUrl":"https://doi.org/10.4236/WJNST.2019.93008","url":null,"abstract":"Coal-fired power plants (CFPP) provide approximately 40% of the world’s energy demand. Naturally occurring radioactive materials (NORM) contained in coal become enriched in coal combustion residues as a result of the elimination of carbon during combustion. The fly ash and bottom ash produced from CFPP may be significant sources of exposure to naturally occurring radionuclides for the population near the combustion plant or ash dumps. Despite this fact, very few studies have actually addressed the relationship of the NORM enrichment factors and the quality of coal used. This paper aims to relate the quality of coal to the enrichment factors for the radionuclides of interest (K40, Ra226, Th232 and Po210) in coal combustion residues from three South African CFPP. The data from other CFPP was also taken into account to establish this correlation. The feedstock coal used in these CFPP is typically low quality, with ash content in the range of 25 - 45 wt%. The radionuclides investigated were determined by gamma spectrometry with the exception of Po210, which was determined by alpha spectrometry. The enrichment factors for the radionuclides of K40, Ra226, Th232 and Po210 in the fly ash and bottom ash (except Po210) was found to be directly proportional to the quality of coal. That is when the ash percentage increased (coal quality decreased) the enrichment factor decreased. The Po210 radionuclide in the bottom ash had an enrichment factor less than one. The relationship between coal quality and enrichment factors for the radionuclides of K40, Ra226, Th232 and Po210 in both the fly ash and bottom ash (except Po210 in the bottom ash) was demonstrated by the following mathematical equation: . This equation may be used as a good indication in obtaining an estimate in determining the enrichment of the mentioned radionuclides in coal combustion products such as fly ash and bottom ash.","PeriodicalId":61566,"journal":{"name":"核科学与技术国际期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41408141","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}

{"title":"Atom’s Nuclear Structure and the Periodic Table of the Chemical Elements","authors":"F. Menegus","doi":"10.4236/WJNST.2019.93010","DOIUrl":"https://doi.org/10.4236/WJNST.2019.93010","url":null,"abstract":"A new method for the identification of the chemical Elements isotopes takes advantage of the isotope Neutron Excess (NE) number. The repre-sentation of the natural isotopes in the Z-NE plane reveals a surprising correspondence between atom’s nuclear and electronic structures. Nuclear directs the atom electronic structure in spite of the alternative set of numbers ruling the two main atom’s compartments. These compartments appear better integrated than actually considered. The Mendeleev periodic table is rooted in the atom’s nuclear structure. Two recent studies arrive to identical conclusions.","PeriodicalId":61566,"journal":{"name":"核科学与技术国际期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43823692","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}

{"title":"Study of Radionuclides and Radon Exhalation Rate in Soil and Sand Samples from Tiba, Luxor, Governorate","authors":"H. Negm, N. K. Ahmed, A. Abbady, Mahasen Reda","doi":"10.4236/WJNST.2019.92006","DOIUrl":"https://doi.org/10.4236/WJNST.2019.92006","url":null,"abstract":"In this study, the natural radionuclides in soil and sand have been measured by using high purity germanium (HPGe) detector. While, radon exhalation rate has been measured by Alpha GUARD. The data analysis is performed to determine 226Ra, 232Th, and 40K activity concentrations in addition to 222Rn exhalation rate. The values of radium equivalent activity (Raeq), external hazard index (Hex), internal hazard index (Hin), and absorbed dose rate were ranged from 46.46 to 124.16 Bq⋅kg−1, 0.07 to 0.33 Bq⋅kg−1, 0.09 to 0.42 Bq⋅kg−1, and 13.24 to 58.37 nGy⋅h−1 respectively in all samples. The area and mass exhalation rates were increased from 9.16 ± 2.83 to 16.18 ± 2.83 Bq⋅m−2⋅h−1 and 1.8 ± 1.34 to 11.35 ± 0.98 Bq⋅kg−1⋅h−1 respectively.","PeriodicalId":61566,"journal":{"name":"核科学与技术国际期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42351077","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}

{"title":"Radiotracers and Nucleonic Control Systems Applied in Industry—Polish Case","authors":"A. Chmielewski, T. Smolinski, M. Rogowski","doi":"10.4236/WJNST.2019.92003","DOIUrl":"https://doi.org/10.4236/WJNST.2019.92003","url":null,"abstract":"Nuclear and radiation technologies play an important role in Polish power sector, oil industry and mining sector, starting from fossil fuels exploitation, their transport and distribution and finally power generation. Application of environmental isotopes, stable and radioactive, in ground water monitoring in the vicinity of open cast lignite mine, and radon monitor applied for miner’s safety in deep coal mines and nucleonic control systems for ash in coal quality control is often used in mining industry. Other applications of nuclear techniques reviewed, concern the oil industry, oil field recovery, transportation pipelines and refineries. Finally, the application of beta radiation-based gauges for air borne fly ash monitoring and radiation technology for flue gas treatment are the examples of using this technique in power sector equipped with coal and oil fired boilers [1]. The radiotracers techniques were used also in glass industry (determination and optimization parameters of the furnaces), cement industry (test of aggregates for the production of cement and optimization media transport in pipelines), metallurgy of Cu, Pb, Zn (investigation of pyrometallurgy processes and new techniques), cellulose industry, environmental and (mainly hydrological) research etc. [2]. The article is brief review of present status of radiotracer and nucleonic gauges techniques as applied to polish industry.","PeriodicalId":61566,"journal":{"name":"核科学与技术国际期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45924312","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}

{"title":"Natural Radioactivity Measurement and Dose Assessment in Soil Samples from Some Selected Areas of Mali","authors":"I. Traore, A. Ba, A. Nourreddine","doi":"10.4236/WJNST.2019.92004","DOIUrl":"https://doi.org/10.4236/WJNST.2019.92004","url":null,"abstract":"This is the first time that a study applies the gamma ray spectroscopy using a high purity germanium to evaluate the terrestrial gamma radiation level by detector in selected regions of Mali. The results reveal that the activity concentrations of naturally occurring 226Ra, 232Th and 40K radionuclides ranges between respectively 17.26 ± 1.81 and 105.43 ± 10.36; 20.41 ± 2.52 and 180.85 ± 19.69; 41.33 ± 8.26 and 627.63 ± 85.62 Bq⋅kg−1. The measures of radium equivalent activity (Raeq), absorbed dose rates (ADR), annual effective dose rate (AEDR), external hazard index (Hex), internal hazard index (Hin) and excess lifetime cancer risk (ELCR) were evaluated. Some of the obtained values exceed the recommended safe levels. Further studies are necessary to constitute a baseline reference data about the terrestrial radiation in Mali.","PeriodicalId":61566,"journal":{"name":"核科学与技术国际期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47786160","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}

{"title":"New Formulation for Semi-Empirical Correlations for Penetration Jets","authors":"R. Pacheco, L. O. Freire, M. S. Rocha, N. Scuro, M. O. Menezes, D. A. Andrade","doi":"10.4236/WJNST.2019.92007","DOIUrl":"https://doi.org/10.4236/WJNST.2019.92007","url":null,"abstract":"Correlations for the extension of a water vapor jet injected in a liquid pool were historically proposed considering the mass flux (kg/m2/s) as a constant. The results were satisfactory, however adjusting the values by linear regression. Although, it presents the following drawbacks: 1) the formulation is only valid for the specific range of data for what it was created; 2) it does not allow the analytical evaluation of the heat transfer coefficient from the extension equation. This paper proposes a new formulation for the calculation of the mass flux, in such a way to remove both of these drawbacks.","PeriodicalId":61566,"journal":{"name":"核科学与技术国际期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42560495","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}

{"title":"Analysis of Neutronics and Thermal-Hydraulic Behavior in a Fuel Pin of Pressurized Water Reactor (PWR)","authors":"M. Zakir, M. Sarkar, A. Hossain","doi":"10.4236/WJNST.2019.92005","DOIUrl":"https://doi.org/10.4236/WJNST.2019.92005","url":null,"abstract":"This paper presents a comparative analysis of different parameters such as enthalpy, moderator temperature, moderator density, flow velocity, pressure, and fuel temperature profile at the fuel pin cell level of PWR. Moreover, in this paper pitches to fuel pin radius ratio are varied from 2.3 to 4. The methods and implementation strategy are such that the coupled neutronic and thermal-hydraulic analysis is executed in a fully one dimensional (1D) manner. The thermal hydraulic is based on moderator/coolant mass and enthalpy equation together with one group diffusion equation for fuel pin. Modelling of fuel pin cell and subchannel is executed in two steps. First, the governing equations are derived assuming that all the parameters appearing in the equations are temperature independent. Fuel pin centerline temperature and radially averaged temperature equations are derived from Fourier laws of thermal conductivity. Finally, diffusion coefficient, fission cross-section and absorbing cross-section are evaluated with respect to the fuel pin temperature. The outcome will be helpful for further neutronics and thermal analysis of PWR. Thermal hydraulics parameter varies the maximum 30 percentage from the lowermost value.","PeriodicalId":61566,"journal":{"name":"核科学与技术国际期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49663528","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}

{"title":"Application of a Mathematical Model to the Sierra Indiana Ore Leaching Process Containing Thorium, by Means of H2SO4 Solution and HCl","authors":"Pedro Orrego, P. Fleming, J. Skeet, Ramón Ávila","doi":"10.4236/wjnst.2019.91002","DOIUrl":"https://doi.org/10.4236/wjnst.2019.91002","url":null,"abstract":"The existence of the thorium element in the ores from the Atacama region, Chile, and its importance in the activities of the nuclear industry, have generated the interest of the Chilean Nuclear Energy Commission (CChEN) to study the technical feasibility of its recovery, like ThO2 through the implementation of hydrometallurgical techniques, such as leaching, solvent extraction, among others. The present work has become a report about the research carried out in the Extractive Metallurgy Area of the Department of Advanced Materials of CChEN, whose objective is to know the behavior of the thorium element when the mineral carrier is leached. The leaching tests were carried out in a glass reactor in batch mode, by mechanical agitation, varying different operational parameters, such as: type of leaching solution, concentration of acid in the solution, system temperature and granulometry of the mineral. The results indicate that there is technical feasibility for the recovery of thorium by leaching the mineral carrier with hydrochloric and/or sulfuric solution. The highest recovery of thorium for a sulfuric solution was 70.0% and for a hydrochloric solution of 83.8%, so the process presents a good efficiency in both cases. For a hydrochloric solution, the mathematical model of the thorium recovery efficiency obtained is: Y=31.14+26.25*X1+8.69*X2−0.82*X3+9.5*X12−0.83*X13−3.71*X23−1.83*X123+6.45 The concentration of HCl and temperature, as well as their interaction, significantly affect the recovery of thorium for Sierra Indiana mineral, as well as temperature and granulometry. The previous model gives a good representativeness of 99.98%. For a sulfuric solution, the mathematical model of the thorium recovery efficiency obtained is: Y=29.78+25.92*X1+0.99*X2−1.05*X3−2.05*X12−9.84*X13−5.26*X23−3.87*X123+15.18 The model indicates that the recovery of thorium for the mineral is significantly affected by the concentration of sulfuric acid, and to a lesser degree by the temperature and granulometry. The model provides a representativeness of 98.3%.","PeriodicalId":61566,"journal":{"name":"核科学与技术国际期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44315700","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}

{"title":"Development of ToSPACE for Pipe Wall Thinning Management in Nuclear Power Plants","authors":"K. Hwang, Hun Yun, Hyeok Seo, G. Lee, Kyung Woo Kim","doi":"10.4236/wjnst.2019.91001","DOIUrl":"https://doi.org/10.4236/wjnst.2019.91001","url":null,"abstract":"A number of piping components in the secondary system of nuclear power plants are exposed to aging mechanisms such as FAC (Flow-Accelerated Corrosion), cavitation, flashing, SPE (Solid Particle Erosion), LDIE (Liquid Droplet Impingement Erosion), etc. Those mechanisms may lead to thinning, leak, or rupture of the components. Due to the pipe ruptures caused by wall thinning in Surry unit 2 of USA in 1986 and in Mihama unit 3 of Japan in 1994, the pipe wall thinning management has emerged as one of the most important issues in nuclear power plants. To manage the pipe wall thinning in the secondary system, Korea has used a foreign program since 1996. As using the foreign country’s program for long term, it was necessary to improve from the perspective of the users. Accordingly, KEPCO-E & C has started to develop the 3D-based pipe wall thinning management program (ToSPACE, Total Solution for Piping And Component Engineering management) from eight years ago, and the development was successful. This paper describes the major functions included in ToSPACE program, such as 3D-based DB (Database) buildup, development of FAC and erosion evaluation theories, UT (Ultra-sonic Test) data reliability analysis, field connection with 3D, automatic establishment of long-term inspection plan, etc. ToSPACE program was developed to allow site engineers performing the selection of inspection quantity at each refueling outage, UT data reliability analysis, UT evaluation, determination of next inspection timing, identification of the inspecting and replacing components in 3D drawings, etc., to access easily.","PeriodicalId":61566,"journal":{"name":"核科学与技术国际期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70889647","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}

{"title":"A Way to Realize Controlled Nuclear Fusion by γ-Laser or γ-Ray","authors":"Shihao Chen, Ziwei Chen","doi":"10.4236/WJNST.2018.84016","DOIUrl":"https://doi.org/10.4236/WJNST.2018.84016","url":null,"abstract":"A way is proposed to realize controllable-nuclear fusion by γ-laser or γ-ray and ordinary laser with their certain frequencies and large enough intensities to irradiate a target ball. The function of ordinary laser is to heat the target nuclei and to realize the inertial confinement for the target nuclei. The target nuclei absorbing γ-photons will be in a certain excited state. The scattering cross-sections will be larger and the ignition temperature will be lower to realize fusion of the nuclei in their excited states than those of the nuclei in their ground states. In contrast with the nuclei applied in conventional fusion, e.g., deutons and tritons, according to the way, the nuclei applied to fusion should have the following characters: the nuclei have their excited states, one of the excited states has higher energy and longer lifetime, and the masses of the nuclei are lesser. Thus, the Lawson conditions can more easily be realized so that the controllable nuclear fusion is possibly realized by the way.","PeriodicalId":61566,"journal":{"name":"核科学与技术国际期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41700878","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}