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Method to measure tree-ring width,density,elemental composition,and stable carbon and oxygen isotopes using one sample 被引量:1
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作者 Chenxi Xu Yaru Zhao +4 位作者 Wenling An Qingyu Zhao Yucheng Liu Masaki Sano Takeshi Nakatsuka 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第3期167-174,共8页
Tree-ring width(RW),density,elemental com-position,and stable carbon and oxygen isotope(δ^(13)C,δ^(18)O)are widely used as proxies to assess climate change,ecology,and environmental pollution;however,a specific pret... Tree-ring width(RW),density,elemental com-position,and stable carbon and oxygen isotope(δ^(13)C,δ^(18)O)are widely used as proxies to assess climate change,ecology,and environmental pollution;however,a specific pretreat-ment has been needed for each proxy.Here,we developed a method by which each proxy can be measured in the same sample.First,the sample is polished for ring width meas-urement.After obtaining the ring width data,the sample is cut to form a 1-mm-thick wood plate.The sample is then mounted in a vertical sample holder,and gradually scanned by an X-ray beam.Simultaneously,the count rates of the fluorescent photons of elements(for chemical characteriza-tion)and a radiographic grayscale image(for wood density)are obtained,i.e.the density and the element content are obtained.Then,cellulose is isolated from the 1-mm wood plate by removal of lignin,and hemicellulose.After producing this cellulose plate,cellulose subsamples are separated by knife under the microscope for inter-annual and intra-annual stable carbon and oxygen isotope(δ^(13)C,δ^(18)O)analysis.Based on this method,RW,density,elemental composition,δ^(13)C,and δ^(18)O can be measured from the same sample,which reduces sample amount and treatment time,and is helpful for multi-proxy comparison and combination research. 展开更多
关键词 Tree-ring width Tree-ring density Tree-ring elemental composition Tree-ring stable carbon and oxygenisotopes
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Multi-Elemental Analysis and 2D Image Mapping within Roots, Leaves and Seeds from O. glaberrima Rice Plants Using Micro-PIXE Technique
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作者 Alassane Traore Anna Ndiaye +6 位作者 Christopher Bongani Mtshali Manneh Baboucarr Jean Paul Latyr Faye Daouda Mbodj Kandiaba Traore Tapha Gueye Ababacar Sadikhe Ndao 《World Journal of Nuclear Science and Technology》 CAS 2024年第2期97-106,共10页
Understanding metal accumulation at organ level in roots, leaves and seeds in O. glaberrima (OG) is crucial for improving physiological and metabolic aspects in growing Asian and African rice in salted areas. The micr... Understanding metal accumulation at organ level in roots, leaves and seeds in O. glaberrima (OG) is crucial for improving physiological and metabolic aspects in growing Asian and African rice in salted areas. The micro-analytical imaging techniques are required to reveal its accumulation and distribution within plant tissues. PIXE studies have been performed to determine different elements in rice plants. The existing microbeam analytical technique at the iThemba LABS will be applied for the 2D image mapping of fresh rice tissues to perform a concentration of low atomic mass elements (such as Al, Si, P, S, Cl, Ca, Ti, Mn, Fe, Cu, Br, Zn and K) with detection limits of typically 1-10 μg/g. Comparison of the distribution of the elements between leaves, root and seed samples using uptake and distribution of elements in particular environmental conditions with potential amount of salt in water have been performed. We are also expecting to indicate metal exclusion as salt tolerance strategies from leaves, root, and seed compartments using matrix correlation between samples and between elements on rice species. 展开更多
关键词 PIXE 2D Mapping Rice Concentration elemental Analysis
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Elemental Compositions of Clinopyroxenes from Southern Okinawa Trough Basalt:Implications for Magmatism and Structural Environment in an Initial Back-Arc Basin
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作者 GUO Kun ZHAI Shikui +3 位作者 FAN Di ZHANG Xia ZHANG Yu ZHU Zhimin 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第3期643-653,共11页
The major and trace elemental compositions of clinopyroxene from basalt were used to characterize the nature of the primitive magma and structural environment beneath the southern Okinawa Trough(SOT),which is an initi... The major and trace elemental compositions of clinopyroxene from basalt were used to characterize the nature of the primitive magma and structural environment beneath the southern Okinawa Trough(SOT),which is an initial back-arc basin at a continental margin.The clinopyroxenes in the basalt were augite with variable Mg^(#)contents(73.37-78.22).The regular variations in major oxide contents(i.e.,CaO,FeO,TiO_(2),and Cr)with decreasing Mg#implied that the clinopyroxenes evolved from being enriched in Mg,Ca,and Cr to being enriched in Fe and Ti.The clinopyroxenes had relatively low rare earth element concentrations(7.51×10^(-6) to 12.68×10^(-6))and negative Eu anomalies(δEu=0.67-0.95).The Kd_(cpx) values of clinopyroxenes(0.2-0.26),which were used to examine whether the clinopyroxene was equilibrated with its host basalt,demonstrate that these clinopyroxene phenocrysts were not captured crystals but were instead produced by crystallization differentiation of the magma.The calculated clinopyroxene crystallization temperatures showed a narrow range of 990-1061℃,and their crystallization pressures ranged from 2.0 to 3.2 kbar.The geochemistry features of these clinopyroxenes indicated that the parent magma belonged to the subalkaline tholeiitic magma series and suggested that the magma experienced crystallization differentiation of olivine,plagioclase,and clinopyroxene,where the crystallization of plagioclase occurred earlier than that of clinopyroxene.Combined with geophysical data,this research on primitive magma and its crystallization differentiation from clinopyroxene indicates that the SOT is in the stage of‘seafloor spreading’and that basaltic rocks produced from tholeiitic magma represent the generation of oceanic crust. 展开更多
关键词 trace elements CLINOPYROXENES southern Okinawa Trough seafloor spreading back-arc basin
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Carbonization mechanism of bamboo (phyllostachys) by means of Fourier Transform Infrared and elemental analysis 被引量:13
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作者 左宋林 高尚愚 +1 位作者 阮锡根 徐柏森 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第1期75-79,共5页
通过测定在200-600℃炭化竹材得到的固体产物的碳、氢、氧元素的含量及它们的红外光谱,研究了在炭化过程中竹材中半纤维素、纤维素及木素的变化规律。结果表明,结合元素分析,红外光谱分析方法是研究竹材炭化机理的有效手段。在200℃以前... 通过测定在200-600℃炭化竹材得到的固体产物的碳、氢、氧元素的含量及它们的红外光谱,研究了在炭化过程中竹材中半纤维素、纤维素及木素的变化规律。结果表明,结合元素分析,红外光谱分析方法是研究竹材炭化机理的有效手段。在200℃以前,竹材中的半纤维素和纤维素的大量羟基断裂,并结合成水而失去。在200-250℃之间,竹材中的纤维素被降解,其中的吡喃型环也遭到破坏。并且木素中的甲氧基也被脱去。竹材中的木素网状结构在250-400℃之间遭到完全的破坏。竹炭中的碳原子在600℃已基本上完成了芳环化。图3表2参15。 展开更多
关键词 BAMBOO CARBONIZATION Fourier Transform infrared elemental analysis
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Standard spectrum measurement and simulation of elemental capture spectroscopy log 被引量:8
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作者 武宏亮 李宁 +2 位作者 兰长林 孔祥忠 柴华 《Applied Geophysics》 SCIE CSCD 2013年第1期109-116,120,共9页
We have established a set of laboratory measurements which is used for capturing element gammma spectrum. Standard captured gamma ray spectra for ten elements, including Si, Ca, Fe, are obtained using the measurements... We have established a set of laboratory measurements which is used for capturing element gammma spectrum. Standard captured gamma ray spectra for ten elements, including Si, Ca, Fe, are obtained using the measurements for the first time in China. We also simulated the capture gamma ray spectra of the ten elements using Monte Carlo methodology with the same parameters of our experimental measurements. Comparing the experiment and simulation results with the data from the International Atomic Energy Agency's Nuclear Data Center, we obtained the standard captured gamma ray spectra of the ten elements, which, as calibration spectra, are used to calibrate the raw spectrum in data processing. This method solved the key problem during the conversion from the original measuring spectrum to the yield of each element in the data processing. The method can effectively improve the accuracy of the element yield calculation. 展开更多
关键词 elemental capture spectroscopy log capture gamma ray spectrum Monte Carlo simulation
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Elemental Composition of the Shell of the Testate Amoeba Difflugia tuberspinifera (Sarcodina:Rhizopoda) 被引量:4
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作者 杨军 Louis BEYENS +1 位作者 沈韫芬 冯伟松 《Zoological Research》 CAS CSCD 北大核心 2004年第5期452-455,共4页
X-ray microanalysis was used to study the elemental composition of the shell of the freshwater testate amoeba Difflugia tuberspinifera Hu et al.,1997 collected from Mulan Lake,Hubei province,China in July 2003.The res... X-ray microanalysis was used to study the elemental composition of the shell of the freshwater testate amoeba Difflugia tuberspinifera Hu et al.,1997 collected from Mulan Lake,Hubei province,China in July 2003.The results show that the shell is composed of ten elements:Si in greater quantity;then Ca and Al;and traces of K,Na,Cl,Fe,Mg,S and P.The analysis of results suggests that D.tuberspinifera in elemental composition appears to occupy a middle position between marine and soil testate amoebae. 展开更多
关键词 Testate amoebae Difflugia tuberspinifera X-ray microanalysis elemental composition
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Separation and enrichment of elemental sulfur and mercury from hydrometallurgical zinc residue using sodium sulfide 被引量:2
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作者 王子阳 蔡晓兰 +3 位作者 张泽彪 张利波 王仕兴 彭金辉 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第2期640-646,共7页
The separation and enrichment of mercury and the recovery of elemental sulfur from flotation sulfur concentrate in zinc pressure leaching process were carried out by sodium sulfide leaching and carbon dioxide precipit... The separation and enrichment of mercury and the recovery of elemental sulfur from flotation sulfur concentrate in zinc pressure leaching process were carried out by sodium sulfide leaching and carbon dioxide precipitating. The results show that the leaching rate of elemental sulfur is more than 98%, and 98.13% of mercury is enriched in the residue, under the optimized conditions of sodium sulfide concentration 1.5 mol/L, liquid/solid ratio 6:1 and leaching time 30 min at room temperature. In addition, the content of mercury is enriched 5.23 times that in the leaching residue. The elemental sulfur is precipitated from leaching solution under conditions of carbon dioxide flow rate 200 mL/min and blowing time 150 min, while solution is stirred adequately. The recovery efficiency of elemental sulfur reaches 97.67%, and the purity of elemental sulfur is 99.75%, meeting the requirements of industrial first-rate product standard according to the national standard of GB/T 2449-2006 (PRC). 展开更多
关键词 flotation sulfur concentrate sodium sulfide leaching carbon dioxide precipitating mercury enrichment elemental sulfurrecovery
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Comparative Studies on the Fine Structure and Elemental Composition of Envelopes of Trachelomonas and Strombomonas (Euglenophyta) 被引量:1
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作者 王全喜 刘洪家 +3 位作者 于晶 孙世琴 张大维 包文美 《Acta Botanica Sinica》 CSCD 2003年第5期601-607,共7页
Fine structure and elemental composition of envelopes of 10 taxa of Trachelomonas and Strombomonas from natural freshwater bodies in China were studied and phylogeny of both genera were discussed. The results indicate... Fine structure and elemental composition of envelopes of 10 taxa of Trachelomonas and Strombomonas from natural freshwater bodies in China were studied and phylogeny of both genera were discussed. The results indicate that iron (Fe) and silicon (Si) are the primary mineral elements of the envelopes. Composition of mineral elements was uncorrelated with envelope color, however, it was highly correlated with the microarchitecture of the envelopes. Content of Si was higher than that of Fe in all species of Strombomonas and some species of Trachelomonas with rough surface. In most species of Trachelomonas, especially those with dense and smoothy surface, content of Fe was higher than that of Si. Based on the above results, we propose to assign those species of Strombomonas into Trachelomonas and consider them as a group of the latter. These species were the most primitive among the group with envelopes in Euglenaceae. 展开更多
关键词 Trachelomonas Strombomonas ENVELOPE elemental composition fine structure
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Gaseous elemental mercury concentration in atmosphere at urban and remote sites in China 被引量:26
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作者 WANG Zhang-wei CHEN Zuo-shuai +1 位作者 DUAN Ning ZHANG Xiao-shan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第2期176-180,共5页
An investigation of gaseous elemental mercury concentration in atmosphere was conducted at Beijing and Guangzhou urban, Yangtze Delta regional sites and China Global Atmosphere Watch Baseline Observatory (CGAWBO) in... An investigation of gaseous elemental mercury concentration in atmosphere was conducted at Beijing and Guangzhou urban, Yangtze Delta regional sites and China Global Atmosphere Watch Baseline Observatory (CGAWBO) in Mt. Waliguan of remote continental area of China. High temporal resolved data were obtained using automated mercury analyzer RA-915^+. Results showed that the overall hourly mean Hg^0 concentrations in Mt. Waliguan were 1.7±1.1 ng/m3 in summer and 0.6±0.08 ng/m^3 in winter. The concentration in Yangtze Delta regional site was 5.4±4.1 ng/m^3, which was much higher than those in Waliguan continental background area and also higher than that found in North America and Europe rural areas. In Beijing urban area the overall hourly mean Hg^0 concentrations were 8.3±3.6 ng/m^3 in winter, 6.5±5.2 ng/m^3 in spring, 4.9±3.3 ng/m^3 in summer, and 6.7±3.5 ng/m^3 in autumn, respectively, and the concentration was 13.5±7.1 ng/m^3 in Guangzhou site. The mean concentration reached the lowest value at 14:00 and the highest at 02:00 or 20:00 in all monitoring campaigns in Beijing and Guangzhou urban areas, which contrasted with the results measured in Yangtze Delta regional site and Mr. Waliguan. The features of concentration and diurnal variation of Hg^0 in Beijing and Guangzhou implied the importance of local anthropogenic sources in contributing to the high Hg^0 concentration in urban areas of China. Contrary seasonal variation patterns of Hg^0 concentration were found between urban and remote sites. In Beijing the highest Hg^0 concentration was in winter and the lowest in summer, while in Mt. Waliguan the Hg^0 concentration in summer was higher than that in winter. These indicated that different processes and factors controlled Hg^0 concentration in urban, regional and remote areas. 展开更多
关键词 gaseous elemental mercury urban/remote sites MONITORING
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Continuous Measurement of Number Concentrations and Elemental Composition of Aerosol Particles for a Dust Storm Event in Beijing 被引量:14
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作者 张仁健 韩志伟 +1 位作者 沈振兴 曹军骥 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2008年第1期89-95,共7页
A continuous measurement of number size distributions and chemical composition of aerosol particles was conducted in Beijing in a dust storm event during 21-26 March 2001. The number concentration of coarse particles ... A continuous measurement of number size distributions and chemical composition of aerosol particles was conducted in Beijing in a dust storm event during 21-26 March 2001. The number concentration of coarse particles ( 〉2μm) increased more significantly than fine particles ( 〈2μm) during the dust storm due to dust weather, while the anthropogenic aerosols collected during the non-dust-storm period tended to be associated with fine particles. Elemental compositions were analyzed by using proton-induced X-ray emission (PIXE). The results show that 20 elements in the dust storm were much higher than in the non-dust-storm period. The calculated soil dust concentration during the dust storm was, on average, 251.8μg m^-3, while it was only 52.1μg m^-3 on non-dust-storm days. The enrichment factors for Mg, A1, P, K, Ca, Ti, Mn, Fe, C1, Cu, Pb, and Zn show small variations between the dust storm and the non-dust-storm period, while those for Ca, Ni and Cr in the dust storm were much lower than those in the non-dust-storm period due to significant local emission sources. A high concentration and enrichment factor for S were observed during the dust storm, which implies that the dust particles were contaminated by aerosol particles from anthropogenic emissions during the long-range transport. A statistical analysis shows that the elemental composition of particles collected during the dust storm in Beijing were better correlated with those of desert soil colleted from desert regions in Inner Mongolia. Air mass back-trajectory analysis further confirmed that this dust storm event could be identified as streaks of dust plumes originating from Inner Mongolia. 展开更多
关键词 PIXE elemental concentration number concentration dust storm
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Elemental Composition and Geochemical Characteristics of Iron-Manganese Nodules in Main Soils of China 被引量:11
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作者 TAN Wen-Feng LIU Fan +2 位作者 LI Yong-Hua HU Hong-Qing HUANG Qiao-Yun 《Pedosphere》 SCIE CAS CSCD 2006年第1期72-81,共10页
Elemental composition and geochemical characteristics of iron-manganese nodules from nine main soils in China were studied by chemical and multivariate statistical analyses to better understand the reactions and funct... Elemental composition and geochemical characteristics of iron-manganese nodules from nine main soils in China were studied by chemical and multivariate statistical analyses to better understand the reactions and functions of iron-manganese nodules in soils and sediment. Compared to the corresponding soils, Mn, Ba, Cd, Co and Pb had strong accumulation, Ni had moderate accumulation, while Ca, Cu, Fe, Na, P, Sr and Zn accumulated to a minor degree in the iron-manganese nodules. In contrast, Si, Al, K, Mg and Ti were reduced in the iron-manganese nodules. The contents of Ba, Cd, Co, Cu, Ni, Pb and Zn were positively and significantly correlated with that of MnO2 in the iron-manganese nodules, while the contents of Cr, Cu, Ni, Pb and Zn were positively and significantly correlated with that of Fe2O3 in soils. Based on a principle component analysis, the elements of iron-manganese nodules were divided into four groups: 1) Mn, Ba, Cd, Co, Cu, Li, Ni, Pb and Zn that were associated with Mn oxides, 2) Fe, Cr and P that were associated with Fe oxides, 3) Si, K, and Mg that were included in the elemental composition of phyllosilicate, and 4) Ca, Na, Al and Ti that existed in todorokite, birnessite, lithiophorite and phyllosilicate. It was suggested that accumulation, mineralization and specific adsorption were involved in the formation processes of soil iron-manganese nodules. 展开更多
关键词 elemental composition geochemical characteristics iron-manganese nodule soil
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Impacting Factors of Elemental Mercury Re-emission across a Lab-scale Simulated Scrubber 被引量:11
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作者 武成利 曹晏 +1 位作者 董众兵 潘伟平 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第3期523-528,共6页
Elemental mercury(Hg^0)re-emissions from slurries and solutions were evaluated in a lab-scale simulated scrubber.Oxidized mercury(Hg^2 +)standard solution was injected into the simulated scrubber at a desired rat... Elemental mercury(Hg^0)re-emissions from slurries and solutions were evaluated in a lab-scale simulated scrubber.Oxidized mercury(Hg^2 +)standard solution was injected into the simulated scrubber at a desired rate to simulate absorbing and dissolving of Hg^2 +in the flue gas across wet flue gas desulfurization(WFGD)systems. PS analytical mercury analyzer was used to continuously determine Hg0re-emission concentrations in the carrier gas from the scrubber.Sulfite ion in the slurry of CaSO3 was validated to reduce Hg ^2+to Hg^ 0,while no Hg ^0 re-emission occurred from slurries of CaSO4 and CaO.Transitional metal ions with low chemical valence such as Fe^2 +,Pb ^2+,Ni ^2+, AsO2^-and Cu ^+were used to prepare solutions with concentration levels of mmol·L^-1.Reduction reaction of Hg^2 +to Hg 0was observed from these solutions.Reduction capabilities for the different transitional metal ions in the solutions were:Pb^2 +〉Cu ^+〉Fe^ 2+〉 AsO2^-〉Ni ^2+. 展开更多
关键词 simulated scrubber elemental mercur-y re-emission impacting factors SULFITE transitional metal ions
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Characteristics of indoor/outdoor PM_(2.5) and elemental components in generic urban, roadside and industrial plant areas of Guangzhou City, China 被引量:10
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作者 HUANG Hong LEE Shun-cheng +3 位作者 CAO Jun-ji ZOU Chang-wei CHEN Xin-geng FAN Shao-jia 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第1期35-43,共9页
Quantitative information on mass concentrations and other characteristics, such as spatial distribution, seasonal variation, indoor/outdoor (I/O) ratio, correlations and sources, of indoor and outdoor PM2.5 and elem... Quantitative information on mass concentrations and other characteristics, such as spatial distribution, seasonal variation, indoor/outdoor (I/O) ratio, correlations and sources, of indoor and outdoor PM2.5 and elemental components in Guangzhou City were provided. Mass concentration of PM2.5 and elemental components were determined by standard weight method and proton-induced X-ray emission (PIXE) method. 18 elements were detected, the results showed positive results. Average indoor and outdoor PM2.5 concentrations in nine sites were in the range of 67.7-74.5μg/m^3 for summer period, and 109.9-123.7 μg/m^3 for winter period, respectively. The sum of 18 elements average concentrations were 5362.6-5533.4 ng/m^3 for summer period, and 8416.8-8900.6 ng/m^3 for winter period, respectively. Average concentrations of PM2.5 and element components showed obvious spatial characteristic, that the concentrations in roadside area and in industrial plant area were higher than those in generic urban area. An obvious seasonal variation characteristic was found for PM2.5 and elemental components, that the concentrations in winter were higher than that in summer. The I/O ratio of PM2.5 and some elemental components presented larger than 1 sometimes. According to indoor/outdoor correlation of PM2.5 and element concentrations, it was found that there were often good relationships between indoor and outdoor concentrations. Enrichment factors were calculated to evaluate anthropogenic versus natural elements sources. 展开更多
关键词 PM2.5 elemental components indoor air
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Characteristics of Elemental Composition of PM_(2.5) in the Spring Period at Tongyu in the Semi-arid Region of Northeast China 被引量:7
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作者 张仁健 符淙斌 +1 位作者 韩志伟 朱崇抒 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2008年第6期922-931,共10页
Continuous observations of mass concentration and elemental composition of aerosol particles (PM2.5) were conducted at Tongyu, a semi-arid site in Northeast China in the spring of 2006. The average mass concentratio... Continuous observations of mass concentration and elemental composition of aerosol particles (PM2.5) were conducted at Tongyu, a semi-arid site in Northeast China in the spring of 2006. The average mass concentration of PM2.5 at Tongyu station was 260.9±274.4 μg m^-3 during the observation period. Nine dust events were monitored with a mean concentration of 528.0±302.7 μgm^-3. The PM2.5 level during non- dust storm (NDS) period was 111.65±63.37 μg m^-3. High mass concentration shows that fine-size particles pollution was very serious in the semi-arid area in Northeast China. The enrichment factor values for crust elements during the dust storm (DS) period are close to those in the NDS period, while the enrichment factor values for pollution elements during the NDS period are much higher than those in the DS period, showing these elements were from anthropogenic sources. The ratios of dust elements to Fe were relative constant during the DS period. The Ca/Fe ratio in dust aerosols at Tongyu is remarkably different from that observed in other source regions and downwind regions. Meteorological analysis shows that dust events at Tongyu are usually associated with dry, low pressure and high wind speed weather conditions. Air mass back-trajectory analysis identified three kinds of general pathways were associated with the aerosol particle transport to Tongyu, and the northwest direction pathway was the main transport route. 展开更多
关键词 dust aerosol mass concentration elemental composition transport pathway
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Data Analysis of Chang'E-1 Gamma-Ray Spectrometer and Global Distribution of U,K,and Th Elemental Abundances 被引量:7
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作者 ZOU Yongliao ZHANG Liyan +17 位作者 LIU Jianzhong MU Lingli REN Xin ZHANG Guangliang CHANG Jin YAN Jun ZHANG Nan ZHANG Hongbo LU Chang LIU Jianjun ZUO Wei SU Yan WEN Weibin BIAN Wei WANG Min XU Chun LI Chunlai OUYANG Ziyuan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第6期1299-1309,共11页
Gamma-ray spectrometer (GRS) is one of the main payloads on the Chang'E-1 (CE-1) lunar probe, mainly aimed to detect the elemental abundances and distributions on the lunar surface. At 03:58 on 28 November 2007,... Gamma-ray spectrometer (GRS) is one of the main payloads on the Chang'E-1 (CE-1) lunar probe, mainly aimed to detect the elemental abundances and distributions on the lunar surface. At 03:58 on 28 November 2007, it performed the first observation of the lunar gamma rays. As of 24 October 2008, 2105 h of effective gamma rays spectra had been acquired by CE-1 GRS, which covers the whole surface of the moon. This paper mainly describes the data processing procedures and methods of deriving the elemental abundances by using the CE-1 GRS time series corrected spectra: first, to bin data into pixels for mapping; then, to perform a background deduction of the cumulative spectra and obtain a peak area of the elements; and finally, to use the elemental abundances inversion model to produce the elemental abundances. Based on these processing methods, the global abundance maps of U, K, and Th at a 5°×5° equal-area pixel are acquired by CE-1 GRS data. The paper gives a preliminary analysis of the uncertainties of the elemental abundances. 展开更多
关键词 Chang'E-1 PAYLOADS gamma rays elemental abundances
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Construction of Inorganic Elemental Fingerprint and Multivariate Statistical Analysis of Marine Traditional Chinese Medicine Meretricis concha from Rushan Bay 被引量:6
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作者 WU Xia ZHENG Kang +2 位作者 ZHAO Fengjia ZHENG Yongjun LI Yantuan 《Journal of Ocean University of China》 SCIE CAS 2014年第4期712-716,共5页
Meretricis concha is a kind of marine traditional Chinese medicine(TCM), and has been commonly used for the treatment of asthma and scald burns. In order to investigate the relationship between the inorganic elemental... Meretricis concha is a kind of marine traditional Chinese medicine(TCM), and has been commonly used for the treatment of asthma and scald burns. In order to investigate the relationship between the inorganic elemental fingerprint and the geographical origin identification of Meretricis concha, the elemental contents of M. concha from five sampling points in Rushan Bay have been determined by means of inductively coupled plasma optical emission spectrometry(ICP-OES). Based on the contents of 14 inorganic elements(Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Se, and Zn), the inorganic elemental fingerprint which well reflects the elemental characteristics was constructed. All the data from the five sampling points were discriminated with accuracy through hierarchical cluster analysis(HCA) and principle component analysis(PCA), indicating that a four-factor model which could explain approximately 80% of the detection data was established, and the elements Al, As, Cd, Cu, Ni and Pb could be viewed as the characteristic elements. This investigation suggests that the inorganic elemental fingerprint combined with multivariate statistical analysis is a promising method for verifying the geographical origin of M. concha, and this strategy should be valuable for the authenticity discrimination of some marine TCM. 展开更多
关键词 Meretricis concha traditional Chinese medicine inorganic elemental fingerprint multivariate statistical analysis Rushan Bay
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TiAl ALLOYS PREPARED BY THERMAL EXTRUSION OF ELEMENTAL POWDER MIXTURES 被引量:6
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作者 Liu Zhijian, Qu Xuanhui, Huang Baiyun Powder Metallurgy Research Institute, Central South University of Technology, Changsha 410083 《中国有色金属学会会刊:英文版》 CSCD 1997年第1期97-101,共5页
TiAlALLOYSPREPAREDBYTHERMALEXTRUSIONOFELEMENTALPOWDERMIXTURES①LiuZhijian,QuXuanhui,HuangBaiyunPowderMetallur... TiAlALLOYSPREPAREDBYTHERMALEXTRUSIONOFELEMENTALPOWDERMIXTURES①LiuZhijian,QuXuanhui,HuangBaiyunPowderMetallurgyResearchInstitu... 展开更多
关键词 POWDER metallurgy TIAL INTERMETALLICS THERMAL EXTRUSION elemental powders
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Elemental geochemical records of seafloor hydrothermal activities in the sediments from the Okinawa Trough 被引量:6
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作者 ZHAI Shikui YU Zenghui DU Tongjun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2007年第4期53-62,共10页
The major and minor element contents in the sediment core H9 from the hydrothermal fields of the Okinawa Trough show a sharp change at the depth of 80 cm. The elements enriched in the upper 80 cm core are those enrich... The major and minor element contents in the sediment core H9 from the hydrothermal fields of the Okinawa Trough show a sharp change at the depth of 80 cm. The elements enriched in the upper 80 cm core are those enriched in the hydrothermal deposits and in the surface sediments recovered from the hydrothermal fields in the trough, which indicates the input of hydrothermal materials. Comparing with other hydrothermal sediments from Mid-ocean Ridges or the Lau Basin, the degree of the enrichment of elements iron, copper,cobah, and nickel is relatively low. However, the enrichment of elements manganese, lead, arsenic, antimony and mercury is remarkable. The average contents of these elements in the upper 80 cm core sediments are three to six times those in the lower section, and 3 - 12 times those in the surface sediments which are not influenced by hydrothermal activities. Hydrothermal activities have contributed significant manganese, lead, arsenic, antimony and mercury to the sediments, and these elements are distinct indicators for the hydrothermal activity in the Okinawa Trough. The significant enrichment of these elements in Core H9 upward from the depth 80 cm indicates the start or the significant enhancing of the hydrothermal activity in this area at about 5 740 aB. P. The average accumulation rate of manganese during this period is about 40 461μg/( cm^2·ka) , which is similar to the hydrothermal sediments in the Lau Basin or the East Pacific Rise. 展开更多
关键词 Okinawa Trough hydrothermal activity elemental geochemical record
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Inorganic Elemental Determinations of Marine Traditional Chinese Medicine Meretricis concha from Jiaozhou Bay:The construction of Inorganic Elemental Fingerprint Based on Chemometric Analysis 被引量:5
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作者 SHAO Mingying LI Xuejie +3 位作者 ZHENG Kang JIANG Man YAN Cuiiwe LI Yantuan 《Journal of Ocean University of China》 SCIE CAS 2016年第2期357-362,共6页
The goal of this paper is to explore the relationship between the inorganic elemental fingerprint and the geographical origin identification ofMeretricis concha, which is a commonly used marine traditional Chinese med... The goal of this paper is to explore the relationship between the inorganic elemental fingerprint and the geographical origin identification ofMeretricis concha, which is a commonly used marine traditional Chinese medicine (TCM) for the treatment of asthma and scald bums. For that, the inorganic elemental contents ofMeretricis concha from five sampling points in Jiaozhou Bay have been determined by means of inductively coupled plasma optical emission spectrometry, and the comparative investigations based on the contents of 14 inorganic elements (A1, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Se and Zn) of the samples from Jiaozhou Bay and the previous reported Rushan Bay were performed. It has been found that the samples from the two bays are ap- proximately classified into two kinds using hierarchical cluster analysis, and a four-factor model based on principle component analysis could explain approximately 75% of the detection data, also linear discriminant analysis can be used to develop a prediction model to distinguish the samples from Jiaozhou Bay and Rushan Bay with accuracy of about 93%. The results of the present investi- gation suggested that the inorganic elemental fingerprint based on the combination of the measured elemental content and chemom- etric analysis is a promising approach for verifying the geographical origin ofMeretricis concha, and this strategy should be valuable for the authenticity discrimination of some marine TCM. 展开更多
关键词 Meretricis concha marine traditional Chinese medicine inorganic elemental fingerprint chemometric analysis
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An improved optimal elemental method for updating finite element models 被引量:5
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作者 段忠东 Spencer B.F. +1 位作者 闫桂荣 欧进萍 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2004年第1期67-74,共8页
The optimal matrix method and optimal elemental method used to update finite element models may not provide accurate results.This situation occurs when the test modal model is incomplete,as is often the case in practi... The optimal matrix method and optimal elemental method used to update finite element models may not provide accurate results.This situation occurs when the test modal model is incomplete,as is often the case in practice.An improved optimal elemental method is presented that defines a new objective function,and as a byproduct,circumvents the need for mass normalized modal shapes,which are also not readily available in practice.To solve the group of nonlinear equations created by the improved optimal method,the Lagrange multiplier method and Matlab function fmincon are employed.To deal with actual complex structures, the float-encoding genetic algorithm(FGA)is introduced to enhance the capability of the improved method.Two examples,a 7- degree of freedom(DOF)mass-spring system and a 53-DOF planar frame,respectively,are updated using the improved method. The example results demonstrate the advantages of the improved method over existing optimal methods,and show that the genetic algorithm is an effective way to update the models used for actual complex structures. 展开更多
关键词 model updating optimal elemental method Lagrangc multiplier method genetic algorithm
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