The full-spectrum least-squares(FSLS) method is introduced to perform quantitative energy-dispersive X-ray fluorescence analysis for unknown solid samples.Based on the conventional least-squares principle, this spectr...The full-spectrum least-squares(FSLS) method is introduced to perform quantitative energy-dispersive X-ray fluorescence analysis for unknown solid samples.Based on the conventional least-squares principle, this spectrum evaluation method is able to obtain the background-corrected and interference-free net peaks, which is significant for quantization analyses. A variety of analytical parameters and functions to describe the features of the fluorescence spectra of pure elements are used and established, such as the mass absorption coefficient, the Gi factor, and fundamental fluorescence formulas. The FSLS iterative program was compiled in the C language. The content of each component should reach the convergence criterion at the end of the calculations. After a basic theory analysis and experimental preparation, 13 national standard soil samples were detected using a spectrometer to test the feasibility of using the algorithm. The results show that the calculated contents of Ti, Fe, Ni, Cu, and Zn have the same changing tendency as the corresponding standard content in the 13 reference samples. Accuracies of 0.35% and 14.03% are obtained, respectively, for Fe and Ti, whose standard concentrations are 8.82% and 0.578%, respectively. However, the calculated results of trace elements (only tens of lg/g) deviate from the standard values. This may be because of measurement accuracy and mutual effects between the elements.展开更多
Eight water bottles from Ebrie lagoon with pollution potency were studied using nuclear chemistry technique and Energy dispersive X-ray fluorescence. This pollution is characterized by pH and conductivity parameters, ...Eight water bottles from Ebrie lagoon with pollution potency were studied using nuclear chemistry technique and Energy dispersive X-ray fluorescence. This pollution is characterized by pH and conductivity parameters, concentrations average in mg/L of metals such Fe (0.731), Mn (0.345), Cr (0.070), Cu (0.014) and concentrations of nutrients known to be pollutants and toxic for living or-ganisms. These heavy metals are dangerous to the lives, the local inhabitants and also a threat to aquatic life since this water is essential for the economical town, Abidjan. According to the Manganese concentration average (0.345 mg) values that higher than WHO (0.05 mg) value, the main likely source of pollu-tants is anthropogenic, industrial and agricultural. This study also shows the use of materials and lubricants near the lagoon that pollute this water.展开更多
在使用能量色散X射线荧光光谱仪定量分析钼铜矿中低含量Cu和Mo元素过程中,X光管的原级谱对测量结果影响非常大。为了降低这一影响,采用蒙特卡洛软件模拟了用Ag,Cu和Mo,Ti三种材质的滤片,在不同厚度情况下对原级谱的影响。模拟结果显示,1...在使用能量色散X射线荧光光谱仪定量分析钼铜矿中低含量Cu和Mo元素过程中,X光管的原级谱对测量结果影响非常大。为了降低这一影响,采用蒙特卡洛软件模拟了用Ag,Cu和Mo,Ti三种材质的滤片,在不同厚度情况下对原级谱的影响。模拟结果显示,1 mm Ti滤片测铜钼元素效果优于0.2 mm Ag滤片、0.02 mm Cu和0.1 mm Mo滤片。根据模拟结果,在实验室用三种滤片对样品进行了实测,谱线图对比显示,用Cu+Mo作滤片测钼元素时,本底计数大于200,用Ag和Ti作滤片测钼元素,几乎没有本底影响。但相同的样品,用Ti作滤片测得钼最高计数为800左右,而用Ag作滤片时测得钼最高计数为300左右。由此可见,用Ti作滤片测钼元素时,X光管原级谱对被测量元素的干扰影响小,其本底低于用银滤片和铜钼滤片。Ti滤片在降低本底影响的同时,钼的计数率最高,说明射线强度损失最少。用Cu+Mo作滤片测铜元素时,铜最高计数为300,用Ag作滤片时铜最高计数为180左右,而用Ti作滤片铜最高计数为500左右。由此可见,在铜元素含量较低时,用Ti作滤片测铜元素,铜的计数率最高,射线强度损失最少。通过公式计算显示:用1 mm Ti滤片测钼铜矿中铜的检出限为5.63 mg·kg^-1,钼的检出限为1.39 mg·kg^-1,检出限明显降低。采用不同含量的标准样品进行测量与化学分析拟合,通过工作曲线可见,高、低含量的样品均具有良好的线性关系,误差水平符合正常化学分析误差标准,R2为0.99及以上,说明1 mm Ti滤片测量精密度高。同一个样品进行多次重复测量,其Cu元素的RSD(%)=0.59,Mo元素的RSD(%)=0.3,均小于1,表明仪器测量稳定性好,样品测试结果具有重现性。研究结果为使用能量色散X射线荧光光谱仪测定钼铜矿中的钼和铜滤光片的选择及其厚度的确定提供了可信的依据,推荐选用1 mm Ti滤片。经过实际现场的检验。该方法稳定可靠,具有重要的实际应用价值。展开更多
This paper investigates the temperature dependence of the specific resistance in annealed V/Al/V/Au （15 nm/85 nm/20 nm/95 nm） contacts on n-A10.4Ga0.6N. Contacts annealed at 700 ℃ and higher temperatures show Ohmic...This paper investigates the temperature dependence of the specific resistance in annealed V/Al/V/Au （15 nm/85 nm/20 nm/95 nm） contacts on n-A10.4Ga0.6N. Contacts annealed at 700 ℃ and higher temperatures show Ohmic behaviour. Annealing at 800 ℃ produces the lowest contact resistance. Samples annealed at 800 ℃have been analysed by using cross-sectional transmission electron microscopy and an energy dispersive x-ray spectrum. Limited reaction depths are observed between V-based contacts and n-AlGaN. The VN grains are found to form in the contact layer of the annealed samples, which can be considered as the key to the successful formation of Ohmic contact. The contact layer adjacent to AlGaN material consists of V Al-Au-N, AlN and AlAu alloys.展开更多
This paper reviews research on coprolites from India,providing the first evidence of microcoprolites from the early Miocene(Aquitanian)Khari Nadi Formation sedimentary succession,exposed about 1.5 km northeast of the ...This paper reviews research on coprolites from India,providing the first evidence of microcoprolites from the early Miocene(Aquitanian)Khari Nadi Formation sedimentary succession,exposed about 1.5 km northeast of the village of Kotada,Kachchh(Kutch)District,Gujarat State,western India.Morphometric and size comparisons(in a statistical framework)with known coprolites from the Mesozoic-Cenozoic successions of India(including those recorded herein)and globally suggest that fishes were the likely producers of the Kotada coprolites.Scanning electron microscopy confirms the presence of fish dental remains within the coprolites,while both Scanning Electron Microscopy(SEM)and Energy Dispersive X-ray Spectroscopy(EDS)reveal the phosphatic nature of the microscopic coprolite specimens(recorded herein)hinting that the producer(s)were predominantly carnivorous(ichthyophagous)in their diet.Furthermore,X-Ray Fluorescence(XRF)analysis of the host and associated lithologies allows us to deduce that the Kotada coprolites were deposited in a shallow marine environment,with possible aerial exposure of the host lithology occurring at some point after deposition.To the best of our knowledge,the present report is the first record of microscopic fish coprolites from India,as well as being the first from the Aquitanian of India and the oldest Neogene record from India.展开更多
[ Objective] The aim was to study the application of scanning electron microscopy（SEM） on the physical property and ideological distri- bution of partials. [ Method] By dint of scanning electron microscopy, the morp...[ Objective] The aim was to study the application of scanning electron microscopy（SEM） on the physical property and ideological distri- bution of partials. [ Method] By dint of scanning electron microscopy, the morphological property of each source and main elements were analyzed. Compared with morphological property of sampling point, the source of particles was determined. [ Result] The results were consistent with the analysis of CMB8.2 chemical mass balance receptor model. Taking the four detection stations in Longyan Normal Training College, Minxi Vocational ＆ Technical College, Longyan University, and Longyan Environment Monitoring Station as examples, the major air pollutants respectively were soil sand, dust of burning coal, second fugitive dust; soil sand, second fugitive dust, vehicle exhausts; second fugitive dust, soil; and second fugitive dust, vehicle exhausts, dust of burning coal. [ Conclusion] The study result had certain guiding significance to the analysis of sources of particles in the atmosphere and atmosphere environment treatment.展开更多
Jingdezhen blue and white imperial porcelain specimens from the Yuan, Ming and Qing dynasties have been systematically analyzed using a nondestructive test method—— energy dispersive X-ray fluorescence analysis (EDX...Jingdezhen blue and white imperial porcelain specimens from the Yuan, Ming and Qing dynasties have been systematically analyzed using a nondestructive test method—— energy dispersive X-ray fluorescence analysis (EDXRF). The derived data of major and trace element compositions have been treated by correspondence analysis. The variation laws of the composition patterns for Jingdezhen blue and white imperial porcelain in different historical periods owing to the change in raw materials, recipe and technology have been discussed, and a time model related to variation of element composition has been preliminarily established, It would be helpful for scientific dating of Jingdezhen blue and white imperial porcelain, and even for the studies on the whole field of identification of ancient ceramics.展开更多
The findings of the Henglingshan group of graves, Guangdong Province, were appraised as one of the ten major archaeological excavations in 2000. The pottery and proto-porcelain samples excavated from the group of grav...The findings of the Henglingshan group of graves, Guangdong Province, were appraised as one of the ten major archaeological excavations in 2000. The pottery and proto-porcelain samples excavated from the group of graves in Henglingshan are very important for studying the development history of Guang-dong ceramics. In this paper, the chemical compositions, micro-structure and physical properties of the samples were systematically analyzed. The results were subjected to multivariate statistical analysis. Different compositional patterns were found for specimens from different periods. The reasons for these variations were discussed. In addition, compared with the pottery and proto-porcelain samples from different production sites in other provinces of China, the obvious regional characters and unique law of the development for ancient ceramics of Guangdong were also discussed.展开更多
Soil erosion and associated sediment redistribution are key environmental problems in Central Argentina.Specific land uses and management practices,such as intensive grazing and crop cultivation,are considered to be s...Soil erosion and associated sediment redistribution are key environmental problems in Central Argentina.Specific land uses and management practices,such as intensive grazing and crop cultivation,are considered to be significantly driving and accelerating these processes.This research focuses on the identification of suitable soil tracers from hot spots of land degradation and sediment fate in an agricultural catchment of central Argentina with erodible loess soils.Using Energy Dispersive X-Ray Fluorescence(EDXRF),elemental concentrations were determined and later used as soil tracers for geochemical characterization.The best set of tracers were identified using two artificial mixtures composed of known proportions of soil sources collected from different lands having contrasting soil uses.Barium,calcium,iron,phosphorus,and titanium were identified for obtaining the best suitable reconstruction of source proportions in the laboratory-prepared artificial mixtures.Then,these elements,as well as the total organic carbon,were applied for pinpointing critical hot spots of erosion within the studied catchment.Feedlots were identified to be the main source of sediments,river banks and dirt roads together are the second most important source.This investigation provides key information for optimizing soil conservation strategies and selecting land management practices and land uses which do not generate great contribution of sediment,preventing pollution of the waterways of the region.展开更多
基金supported by the National Key R&D Project of China(No.2017YFC0602100)the National Natural Science Foundation of China(No.41774147)Sichuan Science and Technology Support Program(No.2015GZ0272)
文摘The full-spectrum least-squares(FSLS) method is introduced to perform quantitative energy-dispersive X-ray fluorescence analysis for unknown solid samples.Based on the conventional least-squares principle, this spectrum evaluation method is able to obtain the background-corrected and interference-free net peaks, which is significant for quantization analyses. A variety of analytical parameters and functions to describe the features of the fluorescence spectra of pure elements are used and established, such as the mass absorption coefficient, the Gi factor, and fundamental fluorescence formulas. The FSLS iterative program was compiled in the C language. The content of each component should reach the convergence criterion at the end of the calculations. After a basic theory analysis and experimental preparation, 13 national standard soil samples were detected using a spectrometer to test the feasibility of using the algorithm. The results show that the calculated contents of Ti, Fe, Ni, Cu, and Zn have the same changing tendency as the corresponding standard content in the 13 reference samples. Accuracies of 0.35% and 14.03% are obtained, respectively, for Fe and Ti, whose standard concentrations are 8.82% and 0.578%, respectively. However, the calculated results of trace elements (only tens of lg/g) deviate from the standard values. This may be because of measurement accuracy and mutual effects between the elements.
文摘Eight water bottles from Ebrie lagoon with pollution potency were studied using nuclear chemistry technique and Energy dispersive X-ray fluorescence. This pollution is characterized by pH and conductivity parameters, concentrations average in mg/L of metals such Fe (0.731), Mn (0.345), Cr (0.070), Cu (0.014) and concentrations of nutrients known to be pollutants and toxic for living or-ganisms. These heavy metals are dangerous to the lives, the local inhabitants and also a threat to aquatic life since this water is essential for the economical town, Abidjan. According to the Manganese concentration average (0.345 mg) values that higher than WHO (0.05 mg) value, the main likely source of pollu-tants is anthropogenic, industrial and agricultural. This study also shows the use of materials and lubricants near the lagoon that pollute this water.
文摘在使用能量色散X射线荧光光谱仪定量分析钼铜矿中低含量Cu和Mo元素过程中,X光管的原级谱对测量结果影响非常大。为了降低这一影响,采用蒙特卡洛软件模拟了用Ag,Cu和Mo,Ti三种材质的滤片,在不同厚度情况下对原级谱的影响。模拟结果显示,1 mm Ti滤片测铜钼元素效果优于0.2 mm Ag滤片、0.02 mm Cu和0.1 mm Mo滤片。根据模拟结果,在实验室用三种滤片对样品进行了实测,谱线图对比显示,用Cu+Mo作滤片测钼元素时,本底计数大于200,用Ag和Ti作滤片测钼元素,几乎没有本底影响。但相同的样品,用Ti作滤片测得钼最高计数为800左右,而用Ag作滤片时测得钼最高计数为300左右。由此可见,用Ti作滤片测钼元素时,X光管原级谱对被测量元素的干扰影响小,其本底低于用银滤片和铜钼滤片。Ti滤片在降低本底影响的同时,钼的计数率最高,说明射线强度损失最少。用Cu+Mo作滤片测铜元素时,铜最高计数为300,用Ag作滤片时铜最高计数为180左右,而用Ti作滤片铜最高计数为500左右。由此可见,在铜元素含量较低时,用Ti作滤片测铜元素,铜的计数率最高,射线强度损失最少。通过公式计算显示:用1 mm Ti滤片测钼铜矿中铜的检出限为5.63 mg·kg^-1,钼的检出限为1.39 mg·kg^-1,检出限明显降低。采用不同含量的标准样品进行测量与化学分析拟合,通过工作曲线可见,高、低含量的样品均具有良好的线性关系,误差水平符合正常化学分析误差标准,R2为0.99及以上,说明1 mm Ti滤片测量精密度高。同一个样品进行多次重复测量,其Cu元素的RSD(%)=0.59,Mo元素的RSD(%)=0.3,均小于1,表明仪器测量稳定性好,样品测试结果具有重现性。研究结果为使用能量色散X射线荧光光谱仪测定钼铜矿中的钼和铜滤光片的选择及其厚度的确定提供了可信的依据,推荐选用1 mm Ti滤片。经过实际现场的检验。该方法稳定可靠,具有重要的实际应用价值。
基金supported by the National Natural Science Foundation of China (Grant Nos. 10774001,60736033,60876041 and 60577030)National Basic Research Program of China (Grant Nos. 2006CB604908 and 2006CB921607)the National Key Basic Research and Development Program of China (973 Project) (Grant No. TG2007CB307004)
文摘This paper investigates the temperature dependence of the specific resistance in annealed V/Al/V/Au （15 nm/85 nm/20 nm/95 nm） contacts on n-A10.4Ga0.6N. Contacts annealed at 700 ℃ and higher temperatures show Ohmic behaviour. Annealing at 800 ℃ produces the lowest contact resistance. Samples annealed at 800 ℃have been analysed by using cross-sectional transmission electron microscopy and an energy dispersive x-ray spectrum. Limited reaction depths are observed between V-based contacts and n-AlGaN. The VN grains are found to form in the contact layer of the annealed samples, which can be considered as the key to the successful formation of Ohmic contact. The contact layer adjacent to AlGaN material consists of V Al-Au-N, AlN and AlAu alloys.
基金funding support from BSIP in the form of In-house Project No.2.17(XIII five-year plan)。
文摘This paper reviews research on coprolites from India,providing the first evidence of microcoprolites from the early Miocene(Aquitanian)Khari Nadi Formation sedimentary succession,exposed about 1.5 km northeast of the village of Kotada,Kachchh(Kutch)District,Gujarat State,western India.Morphometric and size comparisons(in a statistical framework)with known coprolites from the Mesozoic-Cenozoic successions of India(including those recorded herein)and globally suggest that fishes were the likely producers of the Kotada coprolites.Scanning electron microscopy confirms the presence of fish dental remains within the coprolites,while both Scanning Electron Microscopy(SEM)and Energy Dispersive X-ray Spectroscopy(EDS)reveal the phosphatic nature of the microscopic coprolite specimens(recorded herein)hinting that the producer(s)were predominantly carnivorous(ichthyophagous)in their diet.Furthermore,X-Ray Fluorescence(XRF)analysis of the host and associated lithologies allows us to deduce that the Kotada coprolites were deposited in a shallow marine environment,with possible aerial exposure of the host lithology occurring at some point after deposition.To the best of our knowledge,the present report is the first record of microscopic fish coprolites from India,as well as being the first from the Aquitanian of India and the oldest Neogene record from India.
基金Supported by Young Teacher Innovation Program of Jilin University(421031674425)Seed Fund of Jilin University (421021614425)
文摘[ Objective] The aim was to study the application of scanning electron microscopy（SEM） on the physical property and ideological distri- bution of partials. [ Method] By dint of scanning electron microscopy, the morphological property of each source and main elements were analyzed. Compared with morphological property of sampling point, the source of particles was determined. [ Result] The results were consistent with the analysis of CMB8.2 chemical mass balance receptor model. Taking the four detection stations in Longyan Normal Training College, Minxi Vocational ＆ Technical College, Longyan University, and Longyan Environment Monitoring Station as examples, the major air pollutants respectively were soil sand, dust of burning coal, second fugitive dust; soil sand, second fugitive dust, vehicle exhausts; second fugitive dust, soil; and second fugitive dust, vehicle exhausts, dust of burning coal. [ Conclusion] The study result had certain guiding significance to the analysis of sources of particles in the atmosphere and atmosphere environment treatment.
文摘Jingdezhen blue and white imperial porcelain specimens from the Yuan, Ming and Qing dynasties have been systematically analyzed using a nondestructive test method—— energy dispersive X-ray fluorescence analysis (EDXRF). The derived data of major and trace element compositions have been treated by correspondence analysis. The variation laws of the composition patterns for Jingdezhen blue and white imperial porcelain in different historical periods owing to the change in raw materials, recipe and technology have been discussed, and a time model related to variation of element composition has been preliminarily established, It would be helpful for scientific dating of Jingdezhen blue and white imperial porcelain, and even for the studies on the whole field of identification of ancient ceramics.
基金Supported by the National Natural Science Foundation of China (Grant No. 50762006)Origin Exploring of Chinese Civilization Projects (second) (Grant No. 2006BAK21B03)Project of Jiangxi Provincical Department of Eduction (Grant No. GJJ08319)
文摘The findings of the Henglingshan group of graves, Guangdong Province, were appraised as one of the ten major archaeological excavations in 2000. The pottery and proto-porcelain samples excavated from the group of graves in Henglingshan are very important for studying the development history of Guang-dong ceramics. In this paper, the chemical compositions, micro-structure and physical properties of the samples were systematically analyzed. The results were subjected to multivariate statistical analysis. Different compositional patterns were found for specimens from different periods. The reasons for these variations were discussed. In addition, compared with the pottery and proto-porcelain samples from different production sites in other provinces of China, the obvious regional characters and unique law of the development for ancient ceramics of Guangdong were also discussed.
基金CONICET,Argentina PROICO 22/F41 PIP 11220150100334Universidad Nacional de San Luis,Argentina RLA 5076 ARCAL RLA 5064 and ARCAI
文摘Soil erosion and associated sediment redistribution are key environmental problems in Central Argentina.Specific land uses and management practices,such as intensive grazing and crop cultivation,are considered to be significantly driving and accelerating these processes.This research focuses on the identification of suitable soil tracers from hot spots of land degradation and sediment fate in an agricultural catchment of central Argentina with erodible loess soils.Using Energy Dispersive X-Ray Fluorescence(EDXRF),elemental concentrations were determined and later used as soil tracers for geochemical characterization.The best set of tracers were identified using two artificial mixtures composed of known proportions of soil sources collected from different lands having contrasting soil uses.Barium,calcium,iron,phosphorus,and titanium were identified for obtaining the best suitable reconstruction of source proportions in the laboratory-prepared artificial mixtures.Then,these elements,as well as the total organic carbon,were applied for pinpointing critical hot spots of erosion within the studied catchment.Feedlots were identified to be the main source of sediments,river banks and dirt roads together are the second most important source.This investigation provides key information for optimizing soil conservation strategies and selecting land management practices and land uses which do not generate great contribution of sediment,preventing pollution of the waterways of the region.
