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
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
Element profiles of some beach rock samples collected from South East Coast of Tamilnadu, India have been determined using single comparator method of INAA. The geo-chemical behavior of the elements in the region is d...Element profiles of some beach rock samples collected from South East Coast of Tamilnadu, India have been determined using single comparator method of INAA. The geo-chemical behavior of the elements in the region is discussed. The irradiations were done at thermal neutron flux of ~ 1011 cm-2·s-1 at 20kW power using Kalpakkam Mini Reactor (KAMINI), IGCAR, Kalpakkam, Tamilnadu, India. Around 19 elements have been determined from 15 samples by high-resolution gamma spectrometry. The accuracy and precision were evaluated by assaying the irradiated Standard Reference Material (SRM 1646a Estuarine sediment) and were found to be in good agreement with certified values.展开更多
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.
In this paper,computational methods are used to optimize the design of a prompt-gamma neutron activation analysis(PGNAA) system on China Advanced Research Reactor(CARR).Approaches are adopted for obtaining accurate ne...In this paper,computational methods are used to optimize the design of a prompt-gamma neutron activation analysis(PGNAA) system on China Advanced Research Reactor(CARR).Approaches are adopted for obtaining accurate neutron beam parameter and saving the computing time.For the radiation shielding design,the optimizing factors include the cost,weight,volume,machining convenience and background radiation at the detector position.Low background spectrum and high sensitivity are expected.The simulation results,and experiences from international PGNAA community,were used in the design of the CARR PGNAA system.展开更多
The fast and maximum thermal neutron fluxes from the DD-109 neutron generator at the University of Sharjah were experimentally measured by the activation technique using different neutron reactions. The thermal and fa...The fast and maximum thermal neutron fluxes from the DD-109 neutron generator at the University of Sharjah were experimentally measured by the activation technique using different neutron reactions. The thermal and fast neutron fluxes were found to be 2.960 × 10~6 and6.186 × 10~7 n/cm^2 s, respectively. This was done to verify the modeling results for the optimum moderator thickness needed to maximize the thermal neutron flux. The optimum moderator thickness was found to be between 3.5 and4 cm. The present data were compared with the detailed MCNP model-based calculation performed in earlier work to simulate the generator.展开更多
In this paper, an experimental method was described for measuring very slight wear of polymer by using neutron activation analysis (NAA). By means of adopting appropriate neutron flux suitable experimental parameters ...In this paper, an experimental method was described for measuring very slight wear of polymer by using neutron activation analysis (NAA). By means of adopting appropriate neutron flux suitable experimental parameters and measuring technique, the method was performed under the condition without any effect upon the mechanical properties of wearing. The sensitivity of the wear measurements reached the order of magnitude of 10-7g for engineering plastics containing about 1 wt% of zinc. The comparison could be made rapidly between different materials with different resistance to wear. The results were free from the influence of vibration of test systems, elastic deformation of materials, media and moisture absorption, and etc. Combined with autoradiograph, the present technique can be used to investigate the backtransfer of ground debris of metallic fillers from the counter part to the specimen. A multifunctional plane wear testing machine was set up for obtaining wear data and friction coefficient. The present work provides a new, rapid and sensitive measuring technique and also a screening method for the wear of polymers.展开更多
An expert system for neutron activation analysis has been designed on personal computer. It is mainly structured by means of the MDBS GURU, and composed of three subsystems: spectrum analysis, experiment design and da...An expert system for neutron activation analysis has been designed on personal computer. It is mainly structured by means of the MDBS GURU, and composed of three subsystems: spectrum analysis, experiment design and data management. The gamma spectra from multiple channel analyzer can be treated conveniently with conventional methods and/or intellectualized isotope identification based on expert experiences. Fuzzy variable and its algebra are employed for inferring and expression of some conclusions. A procedure for quality control has been created to check the analytical quality. Suggestion of planning an experiment for a certain material can be obtained, and a gamma spectrum can be predicted or simulated. There is a data bank for saving the element concentrations.展开更多
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
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
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
The levels and compartmentalization of Na, Mg, Al, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, As, Se, Br, Rb, Sr, Mo, Sb, I, Cs, Ba, La, Ce, Sm, Eu, Tb, Hf, Ta, Au, Th, and U in Phragmites australis (Cav.) Trin. ex...The levels and compartmentalization of Na, Mg, Al, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, As, Se, Br, Rb, Sr, Mo, Sb, I, Cs, Ba, La, Ce, Sm, Eu, Tb, Hf, Ta, Au, Th, and U in Phragmites australis (Cav.) Trin. ex Steud., Carex conescens L. and Cladophora sericea (Hudson) Kutzing from the Caucasian coast of the Black Sea-Anapa recreational region was investigated by Neutron Activation Analysis. The study touches upon subject of the sediment-to-plant and root-to-leaf elemental transfer as well as of the influence of anthropogenic pollution on wetland ecosystems in zone of resort. The content of the majority of considered elements was found higher in the belowground organs of P. australis than in the aboveground tissues while a reverse regularity was evidenced for C. conescens. The levels of elements decrease from bottom sediments to aquatic plants with the notable exception of the halogens Cl, Br and I that presented 5 to 100 fold higher content in plants than in sediments. The increased levels of As, Mo, and Sb in some soil and sediment samples most probably indicate the anthropogenic pollution. It recommends them for a continuous monitoring of the same area.展开更多
Neutron activation analysis technique of the Gd2O2S:М scintillation ceramics was developed. The concentrations of 15 trace, minor and major elements (As, Ce, Co, Cr, Cs, Eu, Fe, La, Sc, Tb, Zn, Zr, Pr, Gd, Na) have b...Neutron activation analysis technique of the Gd2O2S:М scintillation ceramics was developed. The concentrations of 15 trace, minor and major elements (As, Ce, Co, Cr, Cs, Eu, Fe, La, Sc, Tb, Zn, Zr, Pr, Gd, Na) have been measured with the instrumental neutron activation analysis of the Gd2O2S:Pr sample. The concentrations range of the determined elements is from 3 × 10-8 to 2.0% in mass. The determination limit of the elements was calculated to be (0.6 - 1.3 × 10-8% in mass).展开更多
This manuscript presents an application of calculation methods in neutron activation analysis (NAA) of a large crude oil sample. Monte-Carlo computer code was developed. The computer code calculates neutron cross sect...This manuscript presents an application of calculation methods in neutron activation analysis (NAA) of a large crude oil sample. Monte-Carlo computer code was developed. The computer code calculates neutron cross sections and neutron flux density distribution in the interior large sample. ENDF/B-VII.0 data files and ENSDF BNL-NCS-51655-01/02-Rev data files were used as nuclear databases in our computer code. HPGe planar detector efficiency registration technique and the software were developed for the absolute NAA technique of the large sample. The concentrations of Na, K, Ca, Sc, Cr, Fe, Co, Ni, Cu, Zn, Ga, As, Br, Sr, Zr, Mo, Ag, Sb, Cs, Ba, Ce, Nd, Sm, Eu, Tb, Dy, Ho, Tm, Yb, Lu, Hf, Ta, W, Pt, Au, Hg, Th and U in the crude oil samples of Eastern Siberia oilfield were determined using calculation and relative techniques in the concentration range from 10-9 to 0.5%.展开更多
Instrumental neutron activation analysis(INAA)has been used to determine some chemical element contents(K,Ca,Na,Fe,Zn,Co,Eu,Sb,and Sc)in Traganum nudatum Del(Chenopodiaceae family)consumed in North African rangelands ...Instrumental neutron activation analysis(INAA)has been used to determine some chemical element contents(K,Ca,Na,Fe,Zn,Co,Eu,Sb,and Sc)in Traganum nudatum Del(Chenopodiaceae family)consumed in North African rangelands by sheep livestock.Samples were collected from the area of Djelfa in an arid steppe of Algeria.Results show that pasture halophyte had sufficient levels of K,Ca,Zn,and Co to meet the requirements of ruminants.However,it seems that this halophyte shrub had substantial amounts of Na,higher than the critical level established by the National Research Council(NRC).Eu,Sb,and Sc were within the safety baseline of all the assayed elements recommended by the NRC.The high Na content(~10 g/kg)in this halophytic species requires elevated intake of water by livestock.展开更多
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
The main goal of the current study was to determine the fluorine in the rock samples coal (SARM-18, SARM-19, and SARM-20), opal glass NBS91 and phosphate rock NBS694 using neutron activation analysis. Neutrons energy ...The main goal of the current study was to determine the fluorine in the rock samples coal (SARM-18, SARM-19, and SARM-20), opal glass NBS91 and phosphate rock NBS694 using neutron activation analysis. Neutrons energy of 14 MeV used for irradiation was produced by bombardment of a water-cooled titanium tri-tide target with a beam of deuterons accelerated to a potential of 350 KV to develop a neutron flux (10<sup>8</sup> n⋅cm<sup>-2</sup>⋅s<sup>-1</sup>) on the sample at the neutron generator in the ECN (Netherlands Energy Research Foundation) Petten. This new approach contributes to the existing knowledge of fluorine measurement by the coincidence channels investigation of the positron energy with respect to decay time for each radionuclide element. The present study was designed to determine the fluorine by fast neutron through the reaction of F<sup>19</sup> (n, 2n) F<sup>18</sup>. Interference was treated by irradiating the standard of these elements and reasonable selection of the decay time between the end of irradiation and beginning of counting time. The results of this method indicate that the concentration of fluorine is agreed fairly with literatures.展开更多
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
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
A prompt gamma-neutron activation analysis(PGNAA) system was developed to detect the iron content of iron ore concentrate. Because of the self-absorption effect of gamma-rays and neutrons, and the interference of chlo...A prompt gamma-neutron activation analysis(PGNAA) system was developed to detect the iron content of iron ore concentrate. Because of the self-absorption effect of gamma-rays and neutrons, and the interference of chlorine in the neutron field, the linear relationship between the iron analytical coefficient and total iron content was poor, increasing the error in the quantitative analysis. To solve this problem, gamma-ray self-absorption compensation and a neutron field correction algorithm were proposed, and the experimental results have been corrected using this algorithm. The results show that the linear relationship between the iron analytical coefficient and total iron content was considerably improved after the correction. The linear correlation coefficients reached 0.99 or more.展开更多
文摘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.
文摘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.
文摘Element profiles of some beach rock samples collected from South East Coast of Tamilnadu, India have been determined using single comparator method of INAA. The geo-chemical behavior of the elements in the region is discussed. The irradiations were done at thermal neutron flux of ~ 1011 cm-2·s-1 at 20kW power using Kalpakkam Mini Reactor (KAMINI), IGCAR, Kalpakkam, Tamilnadu, India. Around 19 elements have been determined from 15 samples by high-resolution gamma spectrometry. The accuracy and precision were evaluated by assaying the irradiated Standard Reference Material (SRM 1646a Estuarine sediment) and were found to be in good agreement with certified values.
文摘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.
基金Supported by National Natural Science Foundation of China(No.10805077)
文摘In this paper,computational methods are used to optimize the design of a prompt-gamma neutron activation analysis(PGNAA) system on China Advanced Research Reactor(CARR).Approaches are adopted for obtaining accurate neutron beam parameter and saving the computing time.For the radiation shielding design,the optimizing factors include the cost,weight,volume,machining convenience and background radiation at the detector position.Low background spectrum and high sensitivity are expected.The simulation results,and experiences from international PGNAA community,were used in the design of the CARR PGNAA system.
文摘The fast and maximum thermal neutron fluxes from the DD-109 neutron generator at the University of Sharjah were experimentally measured by the activation technique using different neutron reactions. The thermal and fast neutron fluxes were found to be 2.960 × 10~6 and6.186 × 10~7 n/cm^2 s, respectively. This was done to verify the modeling results for the optimum moderator thickness needed to maximize the thermal neutron flux. The optimum moderator thickness was found to be between 3.5 and4 cm. The present data were compared with the detailed MCNP model-based calculation performed in earlier work to simulate the generator.
文摘In this paper, an experimental method was described for measuring very slight wear of polymer by using neutron activation analysis (NAA). By means of adopting appropriate neutron flux suitable experimental parameters and measuring technique, the method was performed under the condition without any effect upon the mechanical properties of wearing. The sensitivity of the wear measurements reached the order of magnitude of 10-7g for engineering plastics containing about 1 wt% of zinc. The comparison could be made rapidly between different materials with different resistance to wear. The results were free from the influence of vibration of test systems, elastic deformation of materials, media and moisture absorption, and etc. Combined with autoradiograph, the present technique can be used to investigate the backtransfer of ground debris of metallic fillers from the counter part to the specimen. A multifunctional plane wear testing machine was set up for obtaining wear data and friction coefficient. The present work provides a new, rapid and sensitive measuring technique and also a screening method for the wear of polymers.
基金The Project Supported by the National Natural Science Foundation of China
文摘An expert system for neutron activation analysis has been designed on personal computer. It is mainly structured by means of the MDBS GURU, and composed of three subsystems: spectrum analysis, experiment design and data management. The gamma spectra from multiple channel analyzer can be treated conveniently with conventional methods and/or intellectualized isotope identification based on expert experiences. Fuzzy variable and its algebra are employed for inferring and expression of some conclusions. A procedure for quality control has been created to check the analytical quality. Suggestion of planning an experiment for a certain material can be obtained, and a gamma spectrum can be predicted or simulated. There is a data bank for saving the element concentrations.
文摘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.
文摘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.
文摘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.
文摘The levels and compartmentalization of Na, Mg, Al, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, As, Se, Br, Rb, Sr, Mo, Sb, I, Cs, Ba, La, Ce, Sm, Eu, Tb, Hf, Ta, Au, Th, and U in Phragmites australis (Cav.) Trin. ex Steud., Carex conescens L. and Cladophora sericea (Hudson) Kutzing from the Caucasian coast of the Black Sea-Anapa recreational region was investigated by Neutron Activation Analysis. The study touches upon subject of the sediment-to-plant and root-to-leaf elemental transfer as well as of the influence of anthropogenic pollution on wetland ecosystems in zone of resort. The content of the majority of considered elements was found higher in the belowground organs of P. australis than in the aboveground tissues while a reverse regularity was evidenced for C. conescens. The levels of elements decrease from bottom sediments to aquatic plants with the notable exception of the halogens Cl, Br and I that presented 5 to 100 fold higher content in plants than in sediments. The increased levels of As, Mo, and Sb in some soil and sediment samples most probably indicate the anthropogenic pollution. It recommends them for a continuous monitoring of the same area.
文摘Neutron activation analysis technique of the Gd2O2S:М scintillation ceramics was developed. The concentrations of 15 trace, minor and major elements (As, Ce, Co, Cr, Cs, Eu, Fe, La, Sc, Tb, Zn, Zr, Pr, Gd, Na) have been measured with the instrumental neutron activation analysis of the Gd2O2S:Pr sample. The concentrations range of the determined elements is from 3 × 10-8 to 2.0% in mass. The determination limit of the elements was calculated to be (0.6 - 1.3 × 10-8% in mass).
文摘This manuscript presents an application of calculation methods in neutron activation analysis (NAA) of a large crude oil sample. Monte-Carlo computer code was developed. The computer code calculates neutron cross sections and neutron flux density distribution in the interior large sample. ENDF/B-VII.0 data files and ENSDF BNL-NCS-51655-01/02-Rev data files were used as nuclear databases in our computer code. HPGe planar detector efficiency registration technique and the software were developed for the absolute NAA technique of the large sample. The concentrations of Na, K, Ca, Sc, Cr, Fe, Co, Ni, Cu, Zn, Ga, As, Br, Sr, Zr, Mo, Ag, Sb, Cs, Ba, Ce, Nd, Sm, Eu, Tb, Dy, Ho, Tm, Yb, Lu, Hf, Ta, W, Pt, Au, Hg, Th and U in the crude oil samples of Eastern Siberia oilfield were determined using calculation and relative techniques in the concentration range from 10-9 to 0.5%.
基金Supported by MERS(CNEPRU Project No.F-02820140010,entitled:"cophysiologie et valorisation des plantes extremophiles dans la rhabilitation des sols salins et pollus")
文摘Instrumental neutron activation analysis(INAA)has been used to determine some chemical element contents(K,Ca,Na,Fe,Zn,Co,Eu,Sb,and Sc)in Traganum nudatum Del(Chenopodiaceae family)consumed in North African rangelands by sheep livestock.Samples were collected from the area of Djelfa in an arid steppe of Algeria.Results show that pasture halophyte had sufficient levels of K,Ca,Zn,and Co to meet the requirements of ruminants.However,it seems that this halophyte shrub had substantial amounts of Na,higher than the critical level established by the National Research Council(NRC).Eu,Sb,and Sc were within the safety baseline of all the assayed elements recommended by the NRC.The high Na content(~10 g/kg)in this halophytic species requires elevated intake of water by livestock.
文摘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).
文摘The main goal of the current study was to determine the fluorine in the rock samples coal (SARM-18, SARM-19, and SARM-20), opal glass NBS91 and phosphate rock NBS694 using neutron activation analysis. Neutrons energy of 14 MeV used for irradiation was produced by bombardment of a water-cooled titanium tri-tide target with a beam of deuterons accelerated to a potential of 350 KV to develop a neutron flux (10<sup>8</sup> n⋅cm<sup>-2</sup>⋅s<sup>-1</sup>) on the sample at the neutron generator in the ECN (Netherlands Energy Research Foundation) Petten. This new approach contributes to the existing knowledge of fluorine measurement by the coincidence channels investigation of the positron energy with respect to decay time for each radionuclide element. The present study was designed to determine the fluorine by fast neutron through the reaction of F<sup>19</sup> (n, 2n) F<sup>18</sup>. Interference was treated by irradiating the standard of these elements and reasonable selection of the decay time between the end of irradiation and beginning of counting time. The results of this method indicate that the concentration of fluorine is agreed fairly with literatures.
文摘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.
文摘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
基金supported by the National Key Scientific Instrument and Equipment Development Projects(No.2012YQ240121)Liaoning science and technology project(No.2017220010)Changchun Science and Technology Bureau Local Company and College(University,Institution)Cooperation Projects(No.17DY023)
文摘A prompt gamma-neutron activation analysis(PGNAA) system was developed to detect the iron content of iron ore concentrate. Because of the self-absorption effect of gamma-rays and neutrons, and the interference of chlorine in the neutron field, the linear relationship between the iron analytical coefficient and total iron content was poor, increasing the error in the quantitative analysis. To solve this problem, gamma-ray self-absorption compensation and a neutron field correction algorithm were proposed, and the experimental results have been corrected using this algorithm. The results show that the linear relationship between the iron analytical coefficient and total iron content was considerably improved after the correction. The linear correlation coefficients reached 0.99 or more.