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Neutronics analysis of a stacked structure for a subcritical system with LEU solution driven by a D-T neutron source for~(99)Mo production 被引量:4
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作者 Lei Ren Yun-Cheng Han +3 位作者 Jia-Chen Zhang Xiao-Yu Wang Tao-Sheng Li Jie Yu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第11期52-62,共11页
The utilization of neutrons markedly affects the medical isotope yield of a subcritical system driven by an external D-T neutron source.The general methods to improve the utilization of neutrons include moderating mul... The utilization of neutrons markedly affects the medical isotope yield of a subcritical system driven by an external D-T neutron source.The general methods to improve the utilization of neutrons include moderating multiplying,and reflecting neutrons,which ignores the use of neutrons that backscatter to the source direction.In this study,a stacked structure was formed by assembling the multiplier and the low-enriched uranium solution to enable the full use of neutrons that backscatter to the source direction and further improve the utilization of neutrons.A model based on SuperMC was used to evaluate the neutronics and safety behavior of the subcritical system,such as the neutron effective multiplication factor,neutron energy spectrum,medical isotope yield,and heat deposition.Based on the calculation results,when the intensity of the neutron source was 59×10^(13)n/s,the optimized design with a stacked structure could increase the yield of ^(99)Mo to182 Ci/day,which is approximately 16% higher than that obtained with a single-layer structure.The inlet H_(2)O coolant velocity of 1.0 m/s and initial temperature of 20℃ were also found to be sufficient to prevent boiling of the fuel solution. 展开更多
关键词 neutronics analysis Stacked structure ~(99)Mo yield Subcritical system D-T neutron source
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Accumulation of heavy metals in two crop seeds due to soil contamination as determined by neutron activation analysis techniques 被引量:2
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作者 M.F.Abdel Sabour Soil and Water Department, Nuclear Research Center, Cairo, Egypt A.S.Abdel Haleem Hot Lab’s Center, Atomic Energy Authority, Cairo, Egypt A.Sroor, N.Abdel Baset Nuclear Physics Lab, Girls Faculty, Ain Shams University, Egypt R.A.Zaghloul Mubarak City for Scientific Research and Technology, Egypt 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1998年第2期118-124,共7页
Samples of two crop seeds (corn and sesame) grown on different contaminated soil sources were collected and prepared for neutron activation analysis. Soil contamination sources were organic waste compost applied to s... Samples of two crop seeds (corn and sesame) grown on different contaminated soil sources were collected and prepared for neutron activation analysis. Soil contamination sources were organic waste compost applied to soil amendments namely, sewage sludge(Bs) and municipal solid waste (MSW) at 4%, 6% and 8% respectively. The non destructive NAA technique was used to determine some trace elements accumulation in plant seeds. Results revealed that increasing rate of tested organic waste resulted in dramatic increase in tested heavy metals levels in seeds(i.e., Fe, Zn, Co, Cr, Sc and Hg). Sesame seeds showed higher affinity to accumulate trace elements than corn grains in most tested elements. Moreover, MSW addition enhanced the accumulation of tested metals in seeds more than Bs compost. 展开更多
关键词 heavy metals crop seeds neutron activation analysis techniques.
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Application of neutron activation analysis in geochemistry and cosmochemistry 被引量:1
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作者 G.M. Kolesov(Vernadsky Institute of Geochem & Anal Chem.,Russian Academy of Sciences),Kosygin) st.19.117975、Moscow,V-334,Russian 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1994年第3期337-346,共10页
Generalized the use of neutron activation analysis(NAA)in the investigations of unique processes occurring in early stages of formations and evolution of bodies in solar system Out of them the formation of chondrules,... Generalized the use of neutron activation analysis(NAA)in the investigations of unique processes occurring in early stages of formations and evolution of bodies in solar system Out of them the formation of chondrules,emergence of ultra refractory inclusions in carbonaceous chondrites,formation of metallic and silicate phases of iron and stone meteorites,and formation of iron meteorites of different chemical groups Changes in regolite and lunar rock contents,differentiation in the upper mantle matter, identification of earthly meteoritic craters,transportation of cosmic(meteoritic)materials on to the Earth, investigations of unique events like Tunguska fall of the year 1908 and also ore formation studies and processes taking place on geochemical barrier type river-sea,ocean-atmosphere and so on Prospectives of NAA are pointed out 展开更多
关键词 neutron activation analysis GEOCHEMISTRY cosmochemistry Solar system
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A brief introduction to neutron activation analysis in China―history,major achievements,and future perspectives 被引量:1
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作者 Tian Weizhi 《Engineering Sciences》 EI 2009年第4期101-122,共22页
The history,the major achievements in both methodology and applications,the current trends and future perspectives of neutron activation analysis (NAA) in China are briefly described.
关键词 neutron activation analysis (NAA) reactor NAA fast NAA (FNAA) prompt gamma NAA (PGNAA)
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The affect of industrial activities on zinc in alluvial Egyptian soil determined using neutron activation analysis
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作者 Abde.MF Abde.N 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2002年第3期330-332,共3页
Thirty two surface (0—20 cm) soil samples were collected from different locations in Egypt representing non polluted, moderately and highly polluted soils. The aim of this study was to evaluate total Zn content in ... Thirty two surface (0—20 cm) soil samples were collected from different locations in Egypt representing non polluted, moderately and highly polluted soils. The aim of this study was to evaluate total Zn content in alluvial soils of Nile Delta in Egypt by using the delayed neutron activation analysis technique (DNAA), in the irradiation facilities of the first Egyptian research reactor (ET RR 1). The gamma ray spectra were recorded with a hyper pure germanium detection system. The well resolved gamma ray peak at 1116.0 keV was efficiently used for 65 Zn content determination. Zn content in non polluted soil samples ranged between 74.1 and 103.8 ppm with an average of 98.5±5.1 ppm. Zn content in moderately polluted soils ranged between 136.0 and 232.5 ppm with an average of 180.1±32.6 ppm. The highest Zn levels ranging from 240.0 and 733.0 ppm with an average of 410.3±54.4 ppm, were observed in soil samples collected from, either highly polluted agricultural soils exposed to prolonged irrigation with industrial wastewater or surface soil samples from industrial sites. 展开更多
关键词 elemental analysis POLLUTION neutron activation analysis
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An application of a simple computer program for neutron activation analysis
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作者 N.Abdel Basset 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2001年第1期22-24,共3页
A simple computer program is designed for estimation of elemental concentration values in complex samples by neutron activation analysis technique. The program is applied for an Egyptian cement sample which irradiat... A simple computer program is designed for estimation of elemental concentration values in complex samples by neutron activation analysis technique. The program is applied for an Egyptian cement sample which irradiated at the Egyptian Research Reactor 1(ET RR 1). The data obtained is compared with the reported values. The time consumed for such calculations has a remarkable reduction in comparison with the routine work. 展开更多
关键词 neutron activation analysis cement sample EGYPT
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Elemental analysis of some Egyptian ores and industrial iron samples by neutron activation analysis
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作者 A.Srror N.Abdel Basset +1 位作者 A.S.Abdel Haleem A.M.Hassan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2001年第1期115-118,共4页
Elemental analysis of iron ore samples and first industrial iron production prepared by the Egyptian Iron and Steel Company of Helwan near Cairo were determined by instrumental neutron activation analysis technique. ... Elemental analysis of iron ore samples and first industrial iron production prepared by the Egyptian Iron and Steel Company of Helwan near Cairo were determined by instrumental neutron activation analysis technique. Five samples from each kind were irradiated for a 48 hours at a thermal neutron flux of 4×10 12 n/(cm 2.s) in the first Egyptian research reactor ET RR 1. Also the Pneumatic irradiation Rabbit system (PIRS) attached to the reactor in Inshass, was used to measure the elements of short life time. The gamma ray spectra were recorded by means of the hyper pure germanium detection system. The concentration percentage values of major, minor and trace elements are presented. The long and short lived isotopes were considered. A comparative study and a discussion on the elemental concentration values are given. 展开更多
关键词 elemental analysis Egyptian iron samples neutron activation analysis
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Neutron activation analysis of ceramic tiles and its component and radon exhalation rate
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作者 A.El-Shershaby A.Sroor +2 位作者 F.Ahmed A.S.Abdel-Haleem Z.Abdel 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第1期94-99,共6页
The concentrations of 20 trace elements in several ceramics tiles and ceramic composites used in Egypt were elementally analyzed by neutron activation analysis(NAA) technique. The samples and standard were irradiate... The concentrations of 20 trace elements in several ceramics tiles and ceramic composites used in Egypt were elementally analyzed by neutron activation analysis(NAA) technique. The samples and standard were irradiated with reactor for 4 h(in the Second Research Egyptian Reactor(Et-RR-2)) with thermal neutron flux 5.9×10 13 n/(cm 2·s).The gamma-ray spectra obtained were measured for several times by means of the hyper pure germanium detection system(HPGe). Also a solid state nuclear track detector(SSNTD) CR-39, was used to measure the emanation rate of radon for these samples. The radium concentrations were found to vary from 0.39—3.59 ppm and the emanation rates were found to vary from (0.728—5.688) × 10 -4 kg/(m 2· s).The elemental analysis of the ceramic tiles and ceramic composites have a great importance in assigning the physical properties and in turn the quality of the material. 展开更多
关键词 CERAMIC neutron activation analysis(NAA) radon emanation solid state nuclear track detector(SSNTD)
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Neutron activation method in the analysis of environmental objects
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作者 G.M. Kolesov(V.I.Vernadsky Institute of Geochem。&Anal.Chem.,Russian Academy of effciences,Kosygin St.19,Moskow,Russian) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1995年第1期92-100,共9页
NeutronactivationmethodintheanalysisofenvironmentalobjectsG.M.Kolesov(V.I.VernadskyInstituteofGeochem。&Anal.... NeutronactivationmethodintheanalysisofenvironmentalobjectsG.M.Kolesov(V.I.VernadskyInstituteofGeochem。&Anal.Chem.,RussianAcad... 展开更多
关键词 neutron activation analysis:environmental objects nuclear-physical methods.
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Overview of Industrial Materials Detection Based on Prompt Gamma Neutron Activation Analysis Technology
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作者 Jiawen Fan Jie Xu Changming Wang 《World Journal of Engineering and Technology》 2020年第3期389-404,共16页
Prompt gamma neutron activation analysis (PGNAA) is a non-destructive online measurement nuclear analysis method. With its unique advantages, it has been widely used in online analysis of industrial materials such as ... Prompt gamma neutron activation analysis (PGNAA) is a non-destructive online measurement nuclear analysis method. With its unique advantages, it has been widely used in online analysis of industrial materials such as coal, cement, and minerals in recent years. </span><span style="font-family:Verdana;">However, there are many kinds of literature on PGNAA in the field of industrial materials detection, and there are still a few concluding articles. To this end,</span><span style="font-family:Verdana;"> based on the principle of PGNAA online analysis, the status quo and development of the real-time online detection of industrial material components in the field are reviewed and discussed by consulting a large number of domestic and foreign PGNAA related literature and data, to facilitate the reference of relevant scientific researchers. 展开更多
关键词 Prompt Gamma Neutron Activation analysis Method PGNAA On-Line Detection of Industrial Materials
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Elemental Analysis of Air Suspended Particles in Rasht City Using Instrumental Neutron Activation Analysis
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作者 M.V. Masoud F. Aliasghar +2 位作者 K. Hossein K. Yalda B. Mehdi 《Journal of Environmental Science and Engineering》 2010年第10期40-43,共4页
Instrumental neutron activation analysis (INAA) has turned out to be particularly useful in the analysis of suspended particles. This work describes the INAA characterization of air particulate matter collected in R... Instrumental neutron activation analysis (INAA) has turned out to be particularly useful in the analysis of suspended particles. This work describes the INAA characterization of air particulate matter collected in Rasht city, Iran. The particulate matter was collected in two sampling sites for elemental analysis in the period of winter-summer 2009. Samples have been transferred to the environmental laboratory of radiation applications research school. Neutron exposures were performed in Tehran Research Reactor, and measurements were carried out using HPGe detectors coupled to gamma ray spectrometer. In these filter samples, the elements, AI, As, Ba, Br, Ca, CI, Co, Cr, Cu, Fe, Hg, K, La, Mg, Mn, Na, Sb, Sc, Ti, V and Zn were determined using different irradiation and counting protocols. Results show that mean concentration of most air-pollutants in Rasht are lower than those measured in other cities in Iran (Tehran, Shiraz, Isfahan). Collected data were also compared with reported results for other cities in the world. 展开更多
关键词 Instrumental neutron activation analysis air pollutants particulate matter Rasht city toxic elements
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Determination of the Bromine, Manganese and Antimony in Nicotiana tabacum Solanaceae by Using the Neutron Activation Analysis Technique
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作者 Tufic Madi Filho Elson Barros Ferreira +1 位作者 José Roberto Berretta Maria da Conceição Costa Pereira 《Materials Sciences and Applications》 2022年第2期91-106,共16页
Tobacco addiction has been mentioned as a leading cause of preventable illnesses and premature disability. Smoking is the main cause of lung cancer and one of the factors that most contribute to the occurrence of hear... Tobacco addiction has been mentioned as a leading cause of preventable illnesses and premature disability. Smoking is the main cause of lung cancer and one of the factors that most contribute to the occurrence of heart diseases, among others. The herbaceous species Nicotiana tabacum is a plant of the solanaceae family used for tobacco production. Some authors have conducted research about heavy metals and the toxicity of tobacco. It is, frequently, found in low concentrations in the ground, and superficial and underground waters, even though they do not have environmental anthropogenic contributions. However, with the increase of industrial activities and mining together with the agrochemical use of contaminated organic and inorganic fertilizers, an alteration of the geochemical cycle occurs. As a consequence, the natural flow of these materials increases and is released into the biosphere, where they are often accumulated in the superior layer of the ground, accessible to the roots of the plants. During planting and plant development, fertilizers and insecticides, including organochlorines and organophosphates, are used;consequently, the smoke from cigarette smoking presents various toxic substances, such as bromine (Br), manganese (Mn) and antimony (Sb), elements studied in this work. The procedures for the preparation of the samples were carried out in our laboratories and submitted to irradiation with thermal neutrons at Nuclear and Energy Research Institute (IPEN/CNEN-SP), in the Atomic Energy Institute IEA-R1 research reactor. The irradiated material was, then, analyzed by gamma spectrometry, using a high purity germanium detector (HPGe). 展开更多
关键词 Nicotiana tabacum BROMINE MANGANESE ANTIMONY Neutron Activation analysis
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Atmospheric Deposition Study in the Area of Kardzhali Lead-Zinc Plant Based on Moss Analysis
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作者 Gergana Hristozova Savka Marinova +3 位作者 Lyudmila Pavlovna Strelkova Zoya Goryainova Marina Vladimirovna Frontasyeva Trajce Stafilov 《American Journal of Analytical Chemistry》 2014年第14期920-931,共12页
For the first time the moss biomonitoring technique was used to assess the environmental situation in the area affected by a lead zinc plant as one of the most hazardous enterprises in Bulgaria. 77 Hypnum cupressiform... For the first time the moss biomonitoring technique was used to assess the environmental situation in the area affected by a lead zinc plant as one of the most hazardous enterprises in Bulgaria. 77 Hypnum cupressiforme moss samples were collected in the Kardzhali municipality, in the summer and autumn of 2011. The concentrations of a total of 47 elements were determined by means of instrumental epithermal neutron activation analysis (ENAA), atomic absorption spectrometry (AAS) and inductively coupled plasma-atomic emission spectrometry (ICP-AES). Multivariate statistics was applied to characterize the sources of elements detected in the samples. Four groups of elements were found. In comparison to the data averaged for the area outside of the town, the atmospheric deposition loads for the elements of industrial origin in Kardzhali, where the smelter chimney is located, were found to be much higher. Median levels of the measured concentrations for the most toxic metals (Pb, Zn, Cd, As, Cu, In, Sb) were extremely high in this hot spot when compared to the median Bulgarian cross-country data from the 2010/2011 European moss survey. GIS technology was used to produce element distribution maps illustrating deposition patterns of element pollutants in the study area. The results obtained contribute to the Bulgarian environmental research used to study and control the manufacturing processes of a lead-zinc smelter in the town of Kardzhali. 展开更多
关键词 Moss Biomonitoring Heavy Metals Epithermal Neutron Activation analysis Atomic Absorption Spectrometry
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An emergency decision support system for the marine pollution 被引量:1
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作者 宋军 郭俊如 +7 位作者 牟林 刘玉龙 李琰 袁泽轶 李欢 高佳 王国松 姚志刚 《Marine Science Bulletin》 CAS 2015年第2期56-67,共12页
The paper introduces the research progress in an emergency decision support system for marine pollution (EDSS) in China seas and elaborates on the possible role of the Neutron Activation Analysis (NAA) method ther... The paper introduces the research progress in an emergency decision support system for marine pollution (EDSS) in China seas and elaborates on the possible role of the Neutron Activation Analysis (NAA) method therein. To deal with the increasingly grave situation of offshore pollution, the EDSS for China seas has been researching and developing. Based on the prediction and analysis of the ocean three-dimensional current field, this system makes an inference on the possible path of diffusion and influencing area of marine pollutants and possible location of pollution source, and in combination with the environmentally sensitive information related to the technical integration of GIS, it puts forward the decision, making support for minimizing the hazard caused by pollutants. This system has been operationalized and running for many years on the Bohai and Huanghai seas' Marine Pollutants Prediction and Early-Warning, and it has achieved successful experience for many times in the emergencies of China's coastal pollution accidents. At present, the environmental guarantee system directed against heavy metals and radioactive pollutants is in the experimental stage. As the NAA method is especially applicable to the detection of part of heavy metals and radioactive substances, it is of very important practical value for the new system to realize the monitoring, prediction and early-warning of ocean heavy metals and radioactive pollutants. 展开更多
关键词 marine pollution Neutron Activation analysis ocean modeling
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Criticality Search of an Accelerator Driven System Using the ANET Code
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作者 Xenofontos Thalia Savva Panayiota +3 位作者 Melpomeni Varvayanni Jacques Maillard Jorge Silva Nicolas Catsaros 《World Journal of Nuclear Science and Technology》 2021年第1期65-72,共8页
One of the most important safety parameters taken into consideration during the design and actual operation of a nuclear reactor is its control rods adjustment to reach criticality. Concerning the conventional nuclear... One of the most important safety parameters taken into consideration during the design and actual operation of a nuclear reactor is its control rods adjustment to reach criticality. Concerning the conventional nuclear systems, the specification of their rods’ position through the utilization of neutronics codes, deterministic or stochastic, is considered nowadays trivial. However, innovative nuclear reactor concepts such as the Accelerator Driven Systems require sophisticated simulation capabilities of the stochastic neutronics codes since they combine high energy physics, for the spallation-produced neutrons, with classical nuclear technology. ANET (Advanced Neutronics with Evolution and Thermal hydraulic feedback) is an under development stochastic neutronics code, able to cover the broad neutron energy spectrum involved in ADS systems and therefore capable of simulating conventional and hybrid nuclear reactors and calculating important reactor parameters. In this work, ANETS’s reliability to calculate the effective multiplication factor for three core configurations containing control rods of the Kyoto University Critical Assembly, an operating ADS, is examined. The ANET results successfully compare with results produced by well-established stochastic codes such as MCNP6.1. 展开更多
关键词 Monte Carlo neutronics analysis Code Validation Accelerator Driven Systems
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Neutronic calculations of the China dual-functional lithium–lead test blanket module with the parallel discrete ordinates code Hydra 被引量:2
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作者 Guang-Chun Zhang Jie Liu +2 位作者 Liang-Zhi Cao Hong-Chun Wu Xian-Bao Yuan 《Nuclear Science and Techniques》 SCIE CAS CSCD 2020年第8期1-12,共12页
The China dual-functional lithium–lead test blanket module(DFLL-TBM) is a liquid Li Pb blanket concept developed by the Institute of Nuclear Energy Safety Technology of the Chinese Academy of Sciences for testing in ... The China dual-functional lithium–lead test blanket module(DFLL-TBM) is a liquid Li Pb blanket concept developed by the Institute of Nuclear Energy Safety Technology of the Chinese Academy of Sciences for testing in ITER to validate relevant tritium breeding and shielding technologies. In this study, neutronic calculations of DFLL-TBM were carried out using a massively parallel three-dimensional transport code, Hydra, with the Fusion Evaluated Nuclear Data Library/MG. Hydra was developed by the Nuclear Engineering Computational Physics Lab based on the discrete ordinates method and has been devoted to neutronic analysis and shielding evaluation for nuclear facilities. An in-house Monte Carlo code(MCX) was employed to verify the discretized calculation model used by Hydra for the DFLL-TBM calculations. The results showed two key aspects:(1) In most material zones,Hydra solutions are in good agreement with the reference MCX results within 1%, and the maximal relative difference of the neutron flux is merely 3%, demonstrating the correctness of the calculation model;(2) while the current DFLL-TBM design meets the operation shielding requirement of ITER for 4 years, it does not satisfy the tritium self-sufficiency requirement. Compared to the two-step approach, Hydra produces higher accuracies as it does not rely on the homogenization technique during the calculation process. The parallel efficiency tests of Hydra using the DFLL-TBM model also showed that this code maintains a high parallel efficiency on O(100) processors and, as a result, is able to significantly improve computing performance through parallelization. Parameter studies have been carried out by varying the thickness of the beryllium armor layer and the tritium breeding zone to understand the influence of the beryllium layer and breeding zone thickness on tritium breeding performance. This establishes a foundation for further improvement in the tritium production performance of DFLL-TBM. 展开更多
关键词 Discrete ordinates method DFLL-TBM Neutronic analysis Tritium breeding performance
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Optimization of PGNAA device and algorithm for testing basicity index of sinter mixture 被引量:3
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作者 Long Zhao Xu Xu +6 位作者 Jing-Bin Lu Ya-Lin Gong Qing-Feng Song Qing-Min Shang Wei Zhang De-You Yin Yan-Feng Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第1期46-57,共12页
Sinter is the main raw material in the blast furnace iron-making process,and basicity(CaO/SiO2)is an important quality index of sinter.Prompt gamma neutron activation analysis is a multi-elemental online detection tec... Sinter is the main raw material in the blast furnace iron-making process,and basicity(CaO/SiO2)is an important quality index of sinter.Prompt gamma neutron activation analysis is a multi-elemental online detection technology that has been successfully applied in cement,coal,etc.Compared with cement as a raw material,sinter exhibits poor moderation ability and a large neutron absorption cross section.Therefore,cement detection devices are not suitable for sinter mixture detection.In this study,a prompt gamma neutron activation analysis equipment used for testing cement was re-optimized to render it suitable for measuring a sinter mixture.Using Monte Carlo simulation,the comprehensive detection efficiency of the detection device improved by 71.52%.Because of the gamma-ray self-shielding effect of the sinter mixture,the detection errors of CaO and SiO2 are significant.By applying the gamma-ray self-shielding correction algorithm,the detection accuracies improved,and their linear correlation coefficients R2 exceeded 0.99.Furthermore,by applying an improved analyzer to a sintering plant,the first-grade product rate of the factory increased by 4.64%. 展开更多
关键词 Prompt gamma neutron activation analysis SINTER BASICITY Monte Carlo simulation
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STUDY ON OCCURENCE FORM OF PLATINUM IN XINJIE Cu-Pt DEPOSIT BY NAA AND SCANNING PROTON MICROPROBE 被引量:1
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作者 李晓林 朱节清 +5 位作者 谷英梅 邬显慷 童纯菡 汪云亮 帅德权 张成江 《Nuclear Science and Techniques》 SCIE CAS CSCD 1995年第4期212-216,共5页
A combination of NAA and micro-PIXE was used to study concentrations and distributions of platinum group elements (PGE) in ores from Xinjie Cu-Pt deposit.The NAA results of the bulk indicate that the ores belong to th... A combination of NAA and micro-PIXE was used to study concentrations and distributions of platinum group elements (PGE) in ores from Xinjie Cu-Pt deposit.The NAA results of the bulk indicate that the ores belong to the enriched Pt-Pd type.The element concentration maps of scanning micro-PIXE for the ores show that the occurence form of Pt is independent arsenide minerals. No PGE were detected in chalcopyrite of Xinjie Cu-Pt deposit. These information are economically beneficial to the mineral smelting process. 展开更多
关键词 Platinum group elements Neutron activation analysis Scanning proton microprobe China
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Dispersal and Fate of Dredged Materials Disposed of in the Changjiang Estuary Determined by Use of An in Situ Rare Earth Element Tracer
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作者 刘高峰 吴华林 +2 位作者 郭文华 朱建荣 孙连成 《China Ocean Engineering》 SCIE EI 2011年第3期495-506,共12页
To investigate the dispersal pattern and the fate of dredged materials disposed at a pre-selected disposal site, a field tracer experiment was conducted in the North Passage of the Changjiang Estuary during the 2005 f... To investigate the dispersal pattern and the fate of dredged materials disposed at a pre-selected disposal site, a field tracer experiment was conducted in the North Passage of the Changjiang Estuary during the 2005 flood season. Three tons of dredged materials were mixed with 2.792 kg of sodium hexachloroiridate (IV) hexahydrate (SHH), which contained the rare earth element tracer iridum (Ir). Sampling was conducted at pre-selected sections of the estuary on the second, third and fourth day after the release of dredged materials. All samples were evaluated by use of neutron activation analysis. The majority of the dredged material was dispersed nearly parallel to the navigation channel and deposited between the channel and the south dike. Only a small quantity of dredged materials entered or crossed the navigation channel, and the back silting ratio in the navigation channel was about 5%. The dredged materials also dispersed southeasterly beyond two dike heads. 展开更多
关键词 dredged material tracer sediment transport Neutron activation analysis deepwater navigation channel of the Changjiang Estuary
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DETERMINATION OF IMPURITY ELEMENTS IN ALUMINIUM
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作者 侯小琳 张永保 《Nuclear Science and Techniques》 SCIE CAS CSCD 1994年第4期241-245,共5页
Twenty five impurity elements in aluminium applied as reactor material are determined. Titanium and nickel are determined with epithermal neutron activation analysis (NAA), magnesium and silicon by inductance coupling... Twenty five impurity elements in aluminium applied as reactor material are determined. Titanium and nickel are determined with epithermal neutron activation analysis (NAA), magnesium and silicon by inductance coupling plasma emission spectra (ICP), other elements by thermal NAA. The fission coefficient of uraniumis given by an experiment, the interferences of uranium to Ce, Nd, Mo, Zr, La, Sin are subtracted. The detection limits of these methods to all of impurity elements in aluminium are calculated. 展开更多
关键词 Aluminium Impurity element Neutron activation analysis Miniature neutron source reactor Reactor materials
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