The Shanghai Laser Electron Gamma Source(SLEGS)delivers quasi-monochromatic,continuously energy-tunableγ-ray beams.Based on a Photon Activation Analysis(PAA)method,SLEGS built and developed a photon activation analys...The Shanghai Laser Electron Gamma Source(SLEGS)delivers quasi-monochromatic,continuously energy-tunableγ-ray beams.Based on a Photon Activation Analysis(PAA)method,SLEGS built and developed a photon activation analysis platform,including online activation and offiine low background High-Purity Germanium(HPGe)detector measurement systems,as an alternative to direct measurement methods and low-throughput cross-tests.Owing to short half-lives spanning from minutes to days and characteristics such as ease of fabrication,cost-effectiveness,and stability,gold(~(197)Au)and zinc(~(64)Zn)emerge as favorable activation targets for theγ-ray beam flux monitor.Notably,they exhibit a multitude of advantages in monitoring theγ-ray beam flux,typically 10^(5)photons/s,with energies of 13.16 Me V to 19.08 Me V using a 3 mm coarse collimator.In particular,high-fluxγ-ray beam experiments can be conducted effectively.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.
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
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
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
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
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
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
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
Purpose Gamma spectrum of a cement sample is not straightforward to analyze as a result of peak overlapping produced by Compton effect of gamma rays radiated from activated elements in the neutron activation process a...Purpose Gamma spectrum of a cement sample is not straightforward to analyze as a result of peak overlapping produced by Compton effect of gamma rays radiated from activated elements in the neutron activation process and also because of the change into the neutron energy spectrum in the target sample during activation.Methods Artificial neural network(ANN)is an excellent solution for complex and nonlinear systems.Consequently,the use of ANN for quantitative analysis of major cement elements including Ca,Si,Al,and Fe would be very advantageous.Iranian inertial electrostatic confinement fusion device is a fast,monoenergetic and steady neutron generator.It was simulated as a high-energy neutron source for performing neutron activation analysis.In the present study,a library of 29 members of delayed gamma-ray spectra of knowing cement samples were generated via MCNPX version 2.7.Specific photo-peaks related to Ca,Si,Al and Fe obtained from these spectra were used as inputs for ANN(21 of them for training and 8 for testing).Then,using MLP architecture,an ANN model has been presented to model the system to predict the percentages of the elements in cement.The ANN model is optimized to have only a hidden layer with five neurons.Results The comparison between modeling data and results of proposed MLP network shows that there is a good consistency between them.The MAE of training set for Ca,Si and Fe outputs were 0.0351,0.0656 and 0.0660,respectively,and the MAE of testing set for mentioned outputs were 0.0997,0.3046 and 0.8699,respectively.Conclusion Overall,it can be concluded that the defined dispensable errors show that this modeling is a good one as a prediction tool for the mentioned purpose.展开更多
Identifying workers’construction activities or behaviors can enable managers to better monitor labor efficiency and construction progress.However,current activity analysis methods for construction workers rely solely...Identifying workers’construction activities or behaviors can enable managers to better monitor labor efficiency and construction progress.However,current activity analysis methods for construction workers rely solely on manual observations and recordings,which consumes considerable time and has high labor costs.Researchers have focused on monitoring on-site construction activities of workers.However,when multiple workers are working together,current research cannot accu rately and automatically identify the construction activity.This research proposes a deep learning framework for the automated analysis of the construction activities of multiple workers.In this framework,multiple deep neural network models are designed and used to complete worker key point extraction,worker tracking,and worker construction activity analysis.The designed framework was tested at an actual construction site,and activity recognition for multiple workers was performed,indicating the feasibility of the framework for the automated monitoring of work efficiency.展开更多
Analysis of cluster behaviors of the on-coming cluster is an essential measure for high value locations on the battlefield.Unlike target tracking and clustering analysis,cluster behaviors analysis under cluster securi...Analysis of cluster behaviors of the on-coming cluster is an essential measure for high value locations on the battlefield.Unlike target tracking and clustering analysis,cluster behaviors analysis under cluster security requirements remains an open issue,which is a joint analysis of clus-tering,intent reasoning and activity regions.To address this issue,a framework for cluster behav-iors analysis is proposed by incorporating expert knowledge and domain knowledge,and a knowledge-assisted score function with is designed to improve the accuracy of intent reasoning net-work,overcoming the effects of possible knowledge errors.The framework consists of three mod-ules for cluster analysis,intent reasoning and activity region analysis for typical tasks,in which an intent reasoning network is constructed to obtain cluster intents by using a hybrid knowledge and data driven approach.Furthermore,considering the complexity of the battlefield environment,dif-ferent tasks and corresponding activity region optimization functions are designed for cluster activ-ity region analysis,which are vital elements of cluster behaviors analysis.Simulations demonstrate the effectiveness of the proposed cluster behaviors analysis framework.展开更多
bHLH transcription factors,widely exist in various plants,and are vital for the growth and development of these plants.Among them,many have been implicated in anthocyanin biosynthesis across various plants.In the pres...bHLH transcription factors,widely exist in various plants,and are vital for the growth and development of these plants.Among them,many have been implicated in anthocyanin biosynthesis across various plants.In the present study,a PdbHLH57 gene,belonging to the bHLH IIIf group,was characterized,which was isolated and cloned from the colored-leaf poplar‘Zhongshancaiyun’(ZSCY).The cDNA sequence of PdbHLH57 was 1887 base pairs,and the protein encoded by PdbHLH57 had 628 amino acids,the isoelectric point and molecular weight of which were 6.26 and 69.75 kDa,respectively.Through bioinformatics analysis,PdbHLH57 has been classified into the IIIf bHLH subgroup,with many members of this subgroup known to participate in anthocyanin biosynthesis.The subcellular localization analysis conducted in the leaf protoplasts of‘ZSCY’revealed that the PdbHLH57 protein is specifically localized in the nucleus.The transcription activation analysis was also conducted,and the results showed that the PdbHLH57 protein had self-transcription activation.To better explore the functions of the PdbHLH57 protein,two parts of this protein(PdbHLH57-1,PdbHLH57-2)were split to detect their transcriptional activation activity.The results indicated that PdbHLH57-1(1-433aa)had self-transcription activation,and PdbHLH57-2(433-628aa)had no transcription activation.The expression of PdbHLH57 peaked in June during different developmental stages in‘ZSCY’,and it was most highly expressed in the phloem among various tissues.These findings offer a basis for understanding the role of PdbHLH57 in colored-leaf poplar.展开更多
The identification of ore grades is a critical step in mineral resource exploration and mining.Prompt gamma neutron activation analysis(PGNAA)technology employs gamma rays generated by the nuclear reactions between ne...The identification of ore grades is a critical step in mineral resource exploration and mining.Prompt gamma neutron activation analysis(PGNAA)technology employs gamma rays generated by the nuclear reactions between neutrons and samples to achieve the qualitative and quantitative detection of sample components.In this study,we present a novel method for identifying copper grade by combining the vision transformer(ViT)model with the PGNAA technique.First,a Monte Carlo simulation is employed to determine the optimal sizes of the neutron moderator,thermal neutron absorption material,and dimensions of the device.Subsequently,based on the parameters obtained through optimization,a PGNAA copper ore measurement model is established.The gamma spectrum of the copper ore is analyzed using the ViT model.The ViT model is optimized for hyperparameters using a grid search.To ensure the reliability of the identification results,the test results are obtained through five repeated tenfold cross-validations.Long short-term memory and convolutional neural network models are compared with the ViT method.These results indicate that the ViT method is efficient in identifying copper ore grades with average accuracy,precision,recall,F_(1)score,and F_(1)(-)score values of 0.9795,0.9637,0.9614,0.9625,and 0.9942,respectively.When identifying associated minerals,the ViT model can identify Pb,Zn,Fe,and Co minerals with identification accuracies of 0.9215,0.9396,0.9966,and 0.8311,respectively.展开更多
A new method of Neutron Activation Analysis (NAA) for sediment movement study is presented in this paper. Through analyzing the natural sediment, the information about natural tracing agents has been obtained, which c...A new method of Neutron Activation Analysis (NAA) for sediment movement study is presented in this paper. Through analyzing the natural sediment, the information about natural tracing agents has been obtained, which can show the direction of sediment movement and relative discharge of sediment transportation. Test results in some areas, such as Shanton Harbour and Hangzhou Bay, are in good agreement with those from normal hydrologic measurements and some results are not obtainable with the latter. The NAA is economical, practical and reliable, and should be widely used in engineering practice.展开更多
The content analysis of radioactive waste and radiation dose evaluation is considered as one of the important factors in the reactor facility design.This kind of buildings consists of the concrete for the most part an...The content analysis of radioactive waste and radiation dose evaluation is considered as one of the important factors in the reactor facility design.This kind of buildings consists of the concrete for the most part and uses it as the structure and shield of the building.Generally,the concrete has impurities such as cobalt,europium,nickel,and cesium with specific content depending on the production method or manufacturing company.Dominant radioactive nuclides generated from the fundamental components of concrete are considered that it is less contributed to the radiation dose because they are beta decay nuclides in general.Thus,impurities of irradiated concrete in the reactor facilities,are considered occasionally an important evaluation factor for induced activity.In this study,the influence on the activation of impurities in concrete was evaluated from the radiation dose and induced activity calculations.The calculation was evaluated at the bio-shield which is one of the areas with the highest neutron irradiation among the concrete structure in the reactor facility.The results show that radioactive nuclides with gamma decay were produced in these impurities.Moreover,the radiation dose of concrete with impurities was higher than concrete without impurities.The increased radiation dose was quantified through the content of impurities.展开更多
基金supported by National Key Research and Development Program of China(Nos.2022YFA1602404 and2023YFA1606901)the National Natural Science Foundation of China(Nos.12275338,12388102,and U2441221)the Key Laboratory of Nuclear Data Foundation(JCKY2022201C152)。
文摘The Shanghai Laser Electron Gamma Source(SLEGS)delivers quasi-monochromatic,continuously energy-tunableγ-ray beams.Based on a Photon Activation Analysis(PAA)method,SLEGS built and developed a photon activation analysis platform,including online activation and offiine low background High-Purity Germanium(HPGe)detector measurement systems,as an alternative to direct measurement methods and low-throughput cross-tests.Owing to short half-lives spanning from minutes to days and characteristics such as ease of fabrication,cost-effectiveness,and stability,gold(~(197)Au)and zinc(~(64)Zn)emerge as favorable activation targets for theγ-ray beam flux monitor.Notably,they exhibit a multitude of advantages in monitoring theγ-ray beam flux,typically 10^(5)photons/s,with energies of 13.16 Me V to 19.08 Me V using a 3 mm coarse collimator.In particular,high-fluxγ-ray beam experiments can be conducted effectively.
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.
文摘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.
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
文摘Purpose Gamma spectrum of a cement sample is not straightforward to analyze as a result of peak overlapping produced by Compton effect of gamma rays radiated from activated elements in the neutron activation process and also because of the change into the neutron energy spectrum in the target sample during activation.Methods Artificial neural network(ANN)is an excellent solution for complex and nonlinear systems.Consequently,the use of ANN for quantitative analysis of major cement elements including Ca,Si,Al,and Fe would be very advantageous.Iranian inertial electrostatic confinement fusion device is a fast,monoenergetic and steady neutron generator.It was simulated as a high-energy neutron source for performing neutron activation analysis.In the present study,a library of 29 members of delayed gamma-ray spectra of knowing cement samples were generated via MCNPX version 2.7.Specific photo-peaks related to Ca,Si,Al and Fe obtained from these spectra were used as inputs for ANN(21 of them for training and 8 for testing).Then,using MLP architecture,an ANN model has been presented to model the system to predict the percentages of the elements in cement.The ANN model is optimized to have only a hidden layer with five neurons.Results The comparison between modeling data and results of proposed MLP network shows that there is a good consistency between them.The MAE of training set for Ca,Si and Fe outputs were 0.0351,0.0656 and 0.0660,respectively,and the MAE of testing set for mentioned outputs were 0.0997,0.3046 and 0.8699,respectively.Conclusion Overall,it can be concluded that the defined dispensable errors show that this modeling is a good one as a prediction tool for the mentioned purpose.
基金supported by the National Natural Science Foundation of China(52130801,U20A20312,52178271,and 52077213)the National Key Research and Development Program of China(2021YFF0500903)。
文摘Identifying workers’construction activities or behaviors can enable managers to better monitor labor efficiency and construction progress.However,current activity analysis methods for construction workers rely solely on manual observations and recordings,which consumes considerable time and has high labor costs.Researchers have focused on monitoring on-site construction activities of workers.However,when multiple workers are working together,current research cannot accu rately and automatically identify the construction activity.This research proposes a deep learning framework for the automated analysis of the construction activities of multiple workers.In this framework,multiple deep neural network models are designed and used to complete worker key point extraction,worker tracking,and worker construction activity analysis.The designed framework was tested at an actual construction site,and activity recognition for multiple workers was performed,indicating the feasibility of the framework for the automated monitoring of work efficiency.
基金support from the Natural Science Foundation of China (No.61873205)。
文摘Analysis of cluster behaviors of the on-coming cluster is an essential measure for high value locations on the battlefield.Unlike target tracking and clustering analysis,cluster behaviors analysis under cluster security requirements remains an open issue,which is a joint analysis of clus-tering,intent reasoning and activity regions.To address this issue,a framework for cluster behav-iors analysis is proposed by incorporating expert knowledge and domain knowledge,and a knowledge-assisted score function with is designed to improve the accuracy of intent reasoning net-work,overcoming the effects of possible knowledge errors.The framework consists of three mod-ules for cluster analysis,intent reasoning and activity region analysis for typical tasks,in which an intent reasoning network is constructed to obtain cluster intents by using a hybrid knowledge and data driven approach.Furthermore,considering the complexity of the battlefield environment,dif-ferent tasks and corresponding activity region optimization functions are designed for cluster activ-ity region analysis,which are vital elements of cluster behaviors analysis.Simulations demonstrate the effectiveness of the proposed cluster behaviors analysis framework.
基金supported by the Natural Science Foundation of Jiangsu Province,China(BK20242007)the Natural Science Foundation of China(32271916)the Jiangsu Agricultural Science and Technology Innovation Fund[CX(24)3048].
文摘bHLH transcription factors,widely exist in various plants,and are vital for the growth and development of these plants.Among them,many have been implicated in anthocyanin biosynthesis across various plants.In the present study,a PdbHLH57 gene,belonging to the bHLH IIIf group,was characterized,which was isolated and cloned from the colored-leaf poplar‘Zhongshancaiyun’(ZSCY).The cDNA sequence of PdbHLH57 was 1887 base pairs,and the protein encoded by PdbHLH57 had 628 amino acids,the isoelectric point and molecular weight of which were 6.26 and 69.75 kDa,respectively.Through bioinformatics analysis,PdbHLH57 has been classified into the IIIf bHLH subgroup,with many members of this subgroup known to participate in anthocyanin biosynthesis.The subcellular localization analysis conducted in the leaf protoplasts of‘ZSCY’revealed that the PdbHLH57 protein is specifically localized in the nucleus.The transcription activation analysis was also conducted,and the results showed that the PdbHLH57 protein had self-transcription activation.To better explore the functions of the PdbHLH57 protein,two parts of this protein(PdbHLH57-1,PdbHLH57-2)were split to detect their transcriptional activation activity.The results indicated that PdbHLH57-1(1-433aa)had self-transcription activation,and PdbHLH57-2(433-628aa)had no transcription activation.The expression of PdbHLH57 peaked in June during different developmental stages in‘ZSCY’,and it was most highly expressed in the phloem among various tissues.These findings offer a basis for understanding the role of PdbHLH57 in colored-leaf poplar.
基金supported by the National Natural Science Foundation of China(Nos.U2BB2077 and 42374226)the Natural Science Foundation of Jiangxi Province(20232BAB201043 and 20232BCJ23006)the Nuclear energy development project of the National Defense Science and Industry Bureau(Nos.20201192-01,20201192-03).
文摘The identification of ore grades is a critical step in mineral resource exploration and mining.Prompt gamma neutron activation analysis(PGNAA)technology employs gamma rays generated by the nuclear reactions between neutrons and samples to achieve the qualitative and quantitative detection of sample components.In this study,we present a novel method for identifying copper grade by combining the vision transformer(ViT)model with the PGNAA technique.First,a Monte Carlo simulation is employed to determine the optimal sizes of the neutron moderator,thermal neutron absorption material,and dimensions of the device.Subsequently,based on the parameters obtained through optimization,a PGNAA copper ore measurement model is established.The gamma spectrum of the copper ore is analyzed using the ViT model.The ViT model is optimized for hyperparameters using a grid search.To ensure the reliability of the identification results,the test results are obtained through five repeated tenfold cross-validations.Long short-term memory and convolutional neural network models are compared with the ViT method.These results indicate that the ViT method is efficient in identifying copper ore grades with average accuracy,precision,recall,F_(1)score,and F_(1)(-)score values of 0.9795,0.9637,0.9614,0.9625,and 0.9942,respectively.When identifying associated minerals,the ViT model can identify Pb,Zn,Fe,and Co minerals with identification accuracies of 0.9215,0.9396,0.9966,and 0.8311,respectively.
文摘A new method of Neutron Activation Analysis (NAA) for sediment movement study is presented in this paper. Through analyzing the natural sediment, the information about natural tracing agents has been obtained, which can show the direction of sediment movement and relative discharge of sediment transportation. Test results in some areas, such as Shanton Harbour and Hangzhou Bay, are in good agreement with those from normal hydrologic measurements and some results are not obtainable with the latter. The NAA is economical, practical and reliable, and should be widely used in engineering practice.
基金This work was supported by the R&D program throughout the National Fusion Research Institute(NFRI)funded by the Ministry of Science of the Republic of Korea(Project No.:201800000002652),and Innovative Technology Center for Radiation Safety(ITRS).
文摘The content analysis of radioactive waste and radiation dose evaluation is considered as one of the important factors in the reactor facility design.This kind of buildings consists of the concrete for the most part and uses it as the structure and shield of the building.Generally,the concrete has impurities such as cobalt,europium,nickel,and cesium with specific content depending on the production method or manufacturing company.Dominant radioactive nuclides generated from the fundamental components of concrete are considered that it is less contributed to the radiation dose because they are beta decay nuclides in general.Thus,impurities of irradiated concrete in the reactor facilities,are considered occasionally an important evaluation factor for induced activity.In this study,the influence on the activation of impurities in concrete was evaluated from the radiation dose and induced activity calculations.The calculation was evaluated at the bio-shield which is one of the areas with the highest neutron irradiation among the concrete structure in the reactor facility.The results show that radioactive nuclides with gamma decay were produced in these impurities.Moreover,the radiation dose of concrete with impurities was higher than concrete without impurities.The increased radiation dose was quantified through the content of impurities.
