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熔融制样-波长色散和能量色散X射线荧光光谱仪应用于硅酸盐类矿物及疑难样品分析 被引量:8
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作者 李迎春 张磊 +1 位作者 周伟 尚文郁 《岩矿测试》 CAS CSCD 北大核心 2020年第6期828-838,共11页
目前硅酸盐类样品中主量元素一般采用熔融制样X射线荧光光谱法(XRF)测定,不仅单元素测定结果不能超差,而且百分数加和也要满足要求。但对于矿化样品,由于微量元素较高,往往造成不能满足加和质量要求。充分利用波长色散(WD)和能量色散(ED... 目前硅酸盐类样品中主量元素一般采用熔融制样X射线荧光光谱法(XRF)测定,不仅单元素测定结果不能超差,而且百分数加和也要满足要求。但对于矿化样品,由于微量元素较高,往往造成不能满足加和质量要求。充分利用波长色散(WD)和能量色散(ED)复合式X射线荧光光谱仪同时波谱、能谱测定的优势,可使分析人员快速掌握样品组成信息,对评估矿化样品数据质量具有重要意义。本文利用波长-能量色散X射线荧光光谱仪,可在测定主量元素的同时加入更多的微量元素进行测定,而分析时间不延长。主量元素采用波长色散定量,次量元素主要采用能量色散测定,在保证主量元素准确度的情况下,合理设置测量条件,延长能谱测量时间,实现在波长色散12min左右测定主量元素的同时,能够提供14个微量元素如Rb、Sr、Y、Zr、Ba、Cu、Zn的测定结果和10个线性范围较窄或含量较低元素如Co、Ge、Pr、Ta的参考结果,24个微量元素最大检出限为16.76μg/g。通过准确度考核,主量元素测定结果与认定值基本一致,高含量微量元素测定结果亦满足定量分析要求。该方法可使分析人员快速掌握样品组成信息,为提供更加准确、可靠的数据奠定基础,有效地解决矿化疑难样品主量元素测定问题。 展开更多
关键词 波长色散-能量色散x射线荧光光谱 熔融制样 矿化样品 硅酸盐类矿物 主次微量元素
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X射线荧光光谱分析法在土壤样品多元素分析中的应用 被引量:16
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作者 李玉璞 于庆凯 《环境科学与管理》 CAS 2010年第3期99-102,共4页
用Epsilon5偏振能量色散X射线荧光光谱仪测定土壤样品中27种元素。方法的准确度用GBW07323和GSS-32标准样品验证,结果均在标准值范围内。方法的精密度用GBW07401标准样品检验,除Ni、Mo、Se和Pr四种元素的RSD>10%外,其余被测元素的RSD... 用Epsilon5偏振能量色散X射线荧光光谱仪测定土壤样品中27种元素。方法的准确度用GBW07323和GSS-32标准样品验证,结果均在标准值范围内。方法的精密度用GBW07401标准样品检验,除Ni、Mo、Se和Pr四种元素的RSD>10%外,其余被测元素的RSD均<6.3%。实验表明用X射线荧光光谱分析法测定土壤样品中多种元素,具有方法简便、灵敏、准确,检出限低等特点。 展开更多
关键词 偏振-能量色散x射线荧光光谱 土壤样品 多元素分析
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Potential Applications of X-ray Fluorescence Core Scanner in Elemental Analyses of the Muddy Sediments on the Coastal Shelves of China and in Ecological Study 被引量:2
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作者 ZHOU Xin SUN Liguang +1 位作者 LIU Yi WANG Yuhong 《Journal of Ocean University of China》 SCIE CAS 2013年第4期619-623,共5页
Large areas of muddy sediments on the coastal shelves of China provide important samples for studying climate and ecological changes. Analysis of a large number of such samples, which is essential for systematic study... Large areas of muddy sediments on the coastal shelves of China provide important samples for studying climate and ecological changes. Analysis of a large number of such samples, which is essential for systematic study on environmental information recorded in mud areas because of complicated sedimentary environment and variable sedimentary rate, requires a fast and economical method. In this study, we investigated the potential of X-ray fluorescence core scanner (XRFS), a fast analytical instrument for measuring the elemental concentrations of muddy sediments, and observed a significant correlation between the element concentrations of muddy sediments determined by regular X-ray fluorescence spectrometer (XRF) and XRFS, respectively. The correlations are mainly determined by excitation energy of elements, but also influenced by solubility of element ions. Furthermore, we found a striking link between A1 concentrations and marine-originated organic carbon (MOC), a proxy of marine primary productivity. This indicates that MOC is partly controlled by sedimentary characteristics. Therefore, XRFS method has a good potential in fast analysis of a large number of muddy sediment samples, and it can also be used to calibrate MOC in ecological study of coastal seas. 展开更多
关键词 x-ray fluorescence core scanner x-ray fluorescence spectrometer muddy sediment marine-originated organic carbon ecological study
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Effect of Mg^(2+) content in ion-exchanged Shengli lignite on its equilibrium adsorption water content and its mechanism 被引量:1
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作者 刘祥春 冯莉 +2 位作者 王新华 张营 汤海燕 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第2期456-460,共5页
Mg ion-exchanged samples were prepared with acid-washed Shengli lignite.The chemical composition of the ash of the raw sample was determined by X-ray fluorescence.The equilibrium adsorption water contents of samples w... Mg ion-exchanged samples were prepared with acid-washed Shengli lignite.The chemical composition of the ash of the raw sample was determined by X-ray fluorescence.The equilibrium adsorption water contents of samples were determined in a range of relative humidity.The ion-exchange process was characterized by FT-IR,ash content,and p H value.A possible mechanism is proposed for equilibrium adsorption water of ion-exchanged samples at different humidities.The extent of ion-exchange reaction between Mg2+and lignite is controlled by the concentration of Mg2+in Mg SO4solution.The effect of Mg2+on equilibrium adsorption water content varies with relative humidity and content of Mg2+.The factor that controls equilibrium adsorption water content at low relative humidity is water interactions with sorption sites,which are Mg2+–carboxyl group complex.At middle relative humidity capillary force between Mg2+–water clusters Mg+(H2O)nand capillary is more important.At high relative humidity,free water–free water interactions are more significant. 展开更多
关键词 Ion-exchange FT-IR Equilibrium adsorption water content SURFACE
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Prediction of XRF analyzers error for elements on-line assaying using Kalman Filter 被引量:3
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作者 Nakhaei F Sam A +1 位作者 Mosavi MR Nakhaei A 《International Journal of Mining Science and Technology》 SCIE EI 2012年第4期595-601,共7页
Determination of chemical elements assay plays an important role in mineral processing operations.This factor is used to control process accuracy,recovery calculation and plant profitability.The new assaying methods i... Determination of chemical elements assay plays an important role in mineral processing operations.This factor is used to control process accuracy,recovery calculation and plant profitability.The new assaying methods including chemical methods,X-ray fluorescence and atomic absorption spectrometry are advanced and accurate.However,in some applications,such as on-line assaying process,high accuracy is required.In this paper,an algorithm based on Kalman Filter is presented to predict on-line XRF errors.This research has been carried out on the basis of based the industrial real data collection for evaluating the performance of the presented algorithm.The measurements and analysis for this study were conducted at the Sarcheshmeh Copper Concentrator Plant located in Iran.The quality of the obtained results was very satisfied;so that the RMS errors of prediction obtained for Cu and Mo grade assaying errors in rougher feed were less than 0.039 and 0.002 and in final flotation concentration less than 0.58 and 0.074,respectively.The results indicate that the mentioned method is quite accurate to reduce the on-line XRF errors measurement. 展开更多
关键词 PredictionAccuracyx-ray fluorescence Kalman FilterAssayingError
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X射线荧光光谱法与电感耦合等离子体-原子发射光谱法联用测定土壤、水系沉积物、岩石中21种主、次和痕量元素 被引量:16
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作者 徐国栋 葛建华 +3 位作者 金斌 程江 杜谷 董俊 《光谱实验室》 CAS CSCD 北大核心 2011年第1期1-6,共6页
建立了X射线荧光光谱-电感耦合等离子体-原子发射光谱法(XRF-ICP-AES)联用技术测定土壤、水系沉积物和岩石中21种主、次和痕量元素的方法。采用复合熔剂熔融制样法,X射线荧光谱法测定其中的主量元素Al、Ca、Fe、Mg、K、Na、Si。熔融玻... 建立了X射线荧光光谱-电感耦合等离子体-原子发射光谱法(XRF-ICP-AES)联用技术测定土壤、水系沉积物和岩石中21种主、次和痕量元素的方法。采用复合熔剂熔融制样法,X射线荧光谱法测定其中的主量元素Al、Ca、Fe、Mg、K、Na、Si。熔融玻璃样片经φ=10%(体积分数,下同)的HNO3超声波振荡提取,电感耦合等离子体-原子发射光谱法测定其中的次量和痕量元素Ba、Co、Cu、La、Mn、Sr、V、Zn、Y、Sc、Sn、Ta、Ti、Hf。对国家标准土壤样品GBW07401—07408,水系沉积物样品GBW07301—07312,岩石样品GBW07103—07108进行了测定,测定结果与标准值相吻合,方法的准确度、精密度能够满足样品中各元素定量分析的要求。 展开更多
关键词 x射线荧光光谱-电感耦合等离子体-原子发射光谱 土壤 水系沉积物 岩石 主、次和痕量元素
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Selected Major Elements Content in Igneous Rocks of Paraguay by Neutron and X-ray Irradiation
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《Journal of Earth Science and Engineering》 2013年第6期411-415,共5页
Plutonic and volcanic rocks were analyzed by INAA (Instrumental Neutron Activation Analysis) ana XRF (X-ray flurescence) in their major components for its classification. The samples proceed from the sites/regions... Plutonic and volcanic rocks were analyzed by INAA (Instrumental Neutron Activation Analysis) ana XRF (X-ray flurescence) in their major components for its classification. The samples proceed from the sites/regions corresponding to the Precambrian to Paleozoic/Postpaleozoic magmatism in the eastern and western Paraguay. The analysed elements were Si, A1, Na and K and thus the SiO2, AI/O3, Na2O and K2O content determined. The activation were performed in an annular 25Ci Am-Be neutron source with total flux of 5×10^7n.s^-1. The reactions used were (1) ^28Si (n, p) ^27A1, (2) ^27A1 (n, p) ^27Mg; (3) ^23Na (n, γ) ^24Na, the fourth element of interest, potassium, was analysed by XRF. The procedure overall uncertainties were checked as per the analysis of three compositae samples of SiO2: + A12O3 + NaHCO3 + K2CO3 prepared as standards in convenient proportions. The determination of these parameters according to the last recommendations of the IUGS (International Union of Geosciences), permits the classification of the rocks in the categories acid, intermediate, basic and ultrabasie, as well as the identification of the rock family and in certain cases, the norm and their magmatic provenance. 展开更多
关键词 Magmatism in Paraguay activation with Am-Be source xRF in rocks rock classification IUGS recommendations.
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XRF–ICP–AES法测定土壤中的主次元素 被引量:5
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作者 黄元 《化学分析计量》 CAS 2015年第6期73-76,共4页
建立x射线荧光光谱-电感耦合等离子体原子发射光谱法测定土壤中主次元素含量的方法。采用混合熔剂Li2B4O7-LiBO2(质量比为67:33)与试样在高温中熔融制得玻璃熔片,以x荧光法分析土壤样品中主元素(Al,Si,Fe,S,Mn,P,Ti);采用... 建立x射线荧光光谱-电感耦合等离子体原子发射光谱法测定土壤中主次元素含量的方法。采用混合熔剂Li2B4O7-LiBO2(质量比为67:33)与试样在高温中熔融制得玻璃熔片,以x荧光法分析土壤样品中主元素(Al,Si,Fe,S,Mn,P,Ti);采用混合酸消解玻璃熔片,以电感耦合等离子体原子发射光谱法分析土壤样品中次元素(Cd,Cr,Cu,Ni,Pb,Na,K,Ca,Mg,Co)。在选定的条件下,各元素的线性相关系数大于0.9993,方法检出限为0.5~100μg/g,重复测定结果的相对标准偏差均小于5%(n=9)。采用该法对土壤标准物质样品进行测定,测定结果与标准值一致。该方法操作简便、测定结果准确可靠,适用于土壤样品中主次元素的测定。 展开更多
关键词 x射线荧光光谱-感耦合等离子体原子发射光谱 土壤 主次元素
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Characterization and recycling of nickel- and chromium-contained pickling sludge generated in production of stainless steel 被引量:9
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作者 李小明 谢庚 +2 位作者 HOJAMBERDIEV Mirabbos 崔雅茹 赵俊学 《Journal of Central South University》 SCIE EI CAS 2014年第8期3241-3246,共6页
Pickling sludge generated during the neutralization of pickling wastewater with calcium hydroxide in stainless steel pickling process was characterized using X-ray fluorescence spectrometry, X-ray diffractometry, scan... Pickling sludge generated during the neutralization of pickling wastewater with calcium hydroxide in stainless steel pickling process was characterized using X-ray fluorescence spectrometry, X-ray diffractometry, scanning electron microscopy, thermogravimetry and differential scanning calorimetry, etc. The major compositions of pickling sludge are CaF2, CaSO4, Me(OH), (M: Fe, Cr, Ni), and the content of CaF2 is high in the sludge. The melting point of pickling sludge is about 1350℃ and the viscosity is about 0.14 Pa.s at 1450 ℃, which are comparatively lower than those of normal refining slag. After heat treatment, the contents of sulfur and fluorine in the pickling sludge were reduced, confirming the thermal decomposition of sulfate in the sludge. Fluorine in the sludge is reduced by the gaseous SiF4 and A1F3 generated through the reactions of CaF2 with SiO2 and Al2O3. The preliminary results from the reduction test indicate that the sulfur content in the steel is not affected by the presence of sulfur in the sludge. The recovery of nickel is about 40%, and the chromium content changes marginally due to the protective atmosphere under the reduction condition of chromic oxide. The pickling sludge is a potential auxiliary material for the production of stainless steel. 展开更多
关键词 stainless steel pickling sludge CHARACTERIZATION RECYCLING SULFUR FLUORINE
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Extraction of nickel from molybdenum leaching residue of metalliferous black shale by segregation roasting and acid leaching 被引量:4
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作者 楚广 赵思佳 杨天足 《Journal of Central South University》 SCIE EI CAS 2012年第2期340-346,共7页
The recovery of nickel from molybdenum leach residue by the process of segregation roasting-sulfuric acid leaching-solvent extraction was investigated. The residue was characterized by microscopic investigations, usin... The recovery of nickel from molybdenum leach residue by the process of segregation roasting-sulfuric acid leaching-solvent extraction was investigated. The residue was characterized by microscopic investigations, using X-ray fluorescence spectrometry (XRF) and X-ray diffractometry (XRD) techniques and the residue after segregation roasting was characterized by chemical phase analysis method. A series of experiments were conducted to examine the mass ratio of activated carbon (AC) to the residue, segregation roasting time and temperature, sulfuric acid concentration, liquid-to-solid ratio, leaching time, leaching temperature, addition amount of 30% H2O2, stirring speed (a constant) on the leaching efficiency of nickel. A maximum nickel leaching efficiency of 90.5% is achieved with the mass ratio of AC to the residue of 1:2.5, segregation roasting time of 2 h, segregation roasting temperature of 850 ℃, sulfuric acid concentration of 4.5 mol/L, liquid-to-solid ratio of 6:1, leaching time of 5 h, leaching temperature of 80 ℃, addition of 30% H202 of 0.6 mL for 1 g dry residue. Under these optimized conditions, the average leaching efficiency of nickel is 89.3%. The nickel extraction efficiency in the examined conditions is about 99.6%, and the nickel stripping efficiency in the examined conditions is about 99.2%. 展开更多
关键词 metalliferous black shale segregation roasting nickel leaching PC-88A solvent extraction
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Effect of Mischmetal Addition on Catalytic Performance of PtSnNa/ZSM-5 for Propane Dehydrogenation 被引量:4
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作者 Xue Mengwei Zhou Yuming +3 位作者 Huang Li Zhang Yiwei Duan Yongzheng Sheng Xiaoli 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2011年第3期47-52,共6页
The influence of mischmetal addition on physicochcmical properties of PtSnNa/ZSM-5 catalyst was studied by means of XRF, H2 chemisorption, XRD, TPR, NH3-TPD and TPO techniques. The results showed that the presence of ... The influence of mischmetal addition on physicochcmical properties of PtSnNa/ZSM-5 catalyst was studied by means of XRF, H2 chemisorption, XRD, TPR, NH3-TPD and TPO techniques. The results showed that the presence of mischmetal had an obvious impact on the catalytic performance of the PtSnNa/ZSM-5 catalyst. A suitable content of mischmetal not only could enhance the interactions between Pt species and the support, but also inhibit the formation of coke during the reaction, thus improving the catalytic activity and stability. In our experiments, when the content of mischmetal was 3m%, the catalyst exhibited best catalytic performance. However, the continuous addition of mischmetal could promote the reduction of Sn species to metallic tin, which was disadvantageous to the reaction. 展开更多
关键词 mischmetal propane dehydrogenation PtSnNa/ZSM-5 CATALYST
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Propane Dehydrogenation on PtSnNa/AlSBA-15 Catalyst:Influence of Tin as a Promoter 被引量:4
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作者 Duan Yongzheng Zhou Yuming +2 位作者 Zhang Yiwei Sheng Xiaoli Xue Mengwei 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2012年第1期37-45,共9页
PtSnNa/AlSBA-15 catalysts with different amounts of Sn were prepared for propane dehydrogenation.The catalysts were characterized by XRF,BET,H2 chemisorption,NH3-TPD,H2-TPR,and TPO techniques.Test results indicated th... PtSnNa/AlSBA-15 catalysts with different amounts of Sn were prepared for propane dehydrogenation.The catalysts were characterized by XRF,BET,H2 chemisorption,NH3-TPD,H2-TPR,and TPO techniques.Test results indicated that the presence of tin not only modified the acid function and the interfacial character between metal and support,but also reduced the coke deposition effectively.Among these catalysts investigated thereby,the PtSn(0.7%)Na/AlSBA-15 catalyst had the best catalytic performance in terms of propane conversion and stability.With the continuous addition of Sn,more amounts of Sn0 species appeared,which was unfavorable to the reaction.The PtSn(0.7%)Na/AlSBA-15 catalyst was parametrically characterized in order to obtain necessary information to integrate the process operating conditions.A weight hourly space velocity of 3 h-1,a reaction temperature of 610 ℃ and a H2/C3H8 molar ratio of 0.25 were found to be optimum conditions for achieving a higher dehydrogenation activity of the catalyst. 展开更多
关键词 propane dehydrogenation PtSnNa/A1SBA-15 catalyst
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The elementary explore of multiple regression techniques about the fiberglass filter paper's influence on the PM2.5 assaying 被引量:1
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作者 NIU Dun MA Yun-feng +1 位作者 HU Xiao-min ZHOU De-ping 《Journal of Environmental Science and Engineering》 2007年第1期44-47,共4页
The thesis had a deep research about the fiberglass filter paper's influence on the PM2.5 assaying. It has chosen XRF to make a quantitative analysis. Based on multiple regression theory it regard fiberglass filter p... The thesis had a deep research about the fiberglass filter paper's influence on the PM2.5 assaying. It has chosen XRF to make a quantitative analysis. Based on multiple regression theory it regard fiberglass filter paper's quality, element content and the quality of the loaded sample as independent variable, while the element's quality that the sample has collected as dependent variable. Furthermore, it has established four multiple quadric response surface models which concerning Ca by using of Mathematica and Matlab: Y = 0.8649-2.094x1-2.08x2 -1.375x3-10.58x1x2+8.53x1x3+1.549x2x3-3.443x1^2+6.555x2^2+6. 547x3^2; Y = 0.8649-2.094x1-2.08x2-1.375x3; Y = 0.8649 -2.094x2-2.08x2-1.375x3-3.443x1^2+6.525x2^2+6.547x3^2 ; Y =0.8649-2.094x1-2.08x2-1.375x3-10.58x1x2+8.53x1x3+1.549x2x3. After comparison it has finally found the best model. In combining with the sample it present a multiple data fitting analysis method which could adjust the fiberglass filter paper model accordingly. 展开更多
关键词 PM2.5 fiberglass filter paper xRF analysis multiple regression quadric response surface model
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Effect of Exogenous Organic Matter Application on Soil and Plant Elemental Composition in Pot Experiments
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作者 Eubica Pospislova Magdalena Habova +2 位作者 Eva Dolezelova Ida Drapelova Veronika Renciukova 《Journal of Life Sciences》 2016年第3期153-160,共8页
Content of macro- and microelements in plant and soil was studied after biochar, compost, digestate, lignite, and lignohumate application. Pot experiments were carried out in Phytotron CLF Plant Master (Wertingen, Ge... Content of macro- and microelements in plant and soil was studied after biochar, compost, digestate, lignite, and lignohumate application. Pot experiments were carried out in Phytotron CLF Plant Master (Wertingen, Germany). As tested plant lettuce (Lactucasativa) was used. Elemental composition was determined by AAS and XRF spectroscopy. Macronutrients content (Ca, Mg, K, and P) was determined by Mehlich III. Total content of carbon and nitrogen were determined by LECO TruSpec CN analyser. Results showed that different exogenous organic amendments statistically significantly influenced macro and micronutrients content in soil and plant. Satisfactory C/N ratio for soil microorganisms was measured only after compost and digestate application. As concerns hazardous elements, no legislation limits were overstepped after application of the tested organic amendments. Bioavailability and their uptake by plants followed the order: Cd 〉 Mn 〉 Zn 〉 Fe. 展开更多
关键词 Haplic Cambisol macro and micro elements AAS xRF spectroscopy.
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Geochemical characteristics of illite clay rocks from the Shihezi Formation in the Hanxing mining area and its sedimentary environment
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作者 Xu Bohui Ding Shuli +1 位作者 Wang Yu Liu Qinfu 《Mining Science and Technology》 EI CAS 2011年第4期495-500,共6页
We studied the geochemical characteristics of illite clay rocks and their importance from the 5hihezi Formation of Late Permian in the Hanxing mining area by means of ICP-M5 and sequential X-ray fluorescence spectrome... We studied the geochemical characteristics of illite clay rocks and their importance from the 5hihezi Formation of Late Permian in the Hanxing mining area by means of ICP-M5 and sequential X-ray fluorescence spectrometry. The results show that the amount of SiO2 is between 53.37% and 61.58% (by weight) and that of Al2O3 22.40% and 31.31% (by weight). The ratio of SiO2/Al2O3 lies between 1.71 and 2.75. The amount of K2O ranges from 1.11% to 2.56% (by weight). The amounts of Fe and Ti are higher than the theoretical values in illite clay rock would indicate. The amounts of some trace elements, such as Ga, As, Ba, Cu, Th and U are higher than their Clark values, while that of another 23 trace elements are found to be dose to their Clark values. The amounts of REE range from 22.59 to 570.54 μg/g, with an average of 163.23μg/g. The ratios of LREE/HREE range from 5.41 to 21.82, with an average of 8.87. These characteristics show that LREE are much richer in content than HREE. The REE distribution patterns of our samples were characterized by clearly negative Ce and Eu anomalies. We analyzed the sedimentary environment of the Hanxing mining area in Late Permian by the characteristic element ratio method. The ratios of Mn/Fe range from 0 to 0.0168, which are lower than those in a marine sedimentary environment. The ratios of Sr/Ba (0.20-0.41) are less than 1. These are all indications that the sediments of the Hanxing mining area in Late Permian form largely a continental sedimentary environment. The sedimentary water is freshwater, a conclusion reached on the basis of the ratios of Th/U (2.66-6.62) and of Ca/(Ca + Fe) (0.01-0.059); the average ratio of Fe2+/Fe3+ is 4.8. The sedimentary water condition is weakly acidic and weakly oxidative-weakly reductive, a conclusion reached on the basis of ratios of Fe2+/Fe3+ (4.8) and of Ceanom (-0.08). 展开更多
关键词 Hanxing mining arealllite Trace elements Geochemical Sedimentary environment
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溴化丁基橡胶溴含量的测定 被引量:7
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作者 王娟 李树新 郭文莉 《合成橡胶工业》 CAS CSCD 北大核心 2007年第6期423-426,共4页
分别用1H-核磁共振(1H-NMR)法、X射线-荧光光谱(XRF)法和化学滴定法测定了溴化丁基橡胶(BBR)的溴含量。结果表明,1H-NMR法与XRF法操作简单,测试周期短,且分析结果的准确度较高;化学滴定法测试周期较长,分析结果偏低。
关键词 溴化丁基橡胶 溴含量 ^1H-核磁共振 x射线-荧光光谱 化学滴定
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数理统计方法在仪器运行检查中的应用
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作者 彭宇 《光谱实验室》 CAS CSCD 2001年第4期534-535,共2页
本文以 Philips PW140 4型 X射线荧光光谱仪的使用为例 ,应用数理统计理论 ,提出了一种仪器运行状态检查的方法 ,该方法具有简便、快速的特点 ,非常适合生产要求。
关键词 数理统计 运行检查 分析仪器 x射线-荧光光谱 工作状态
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In-Situ Differentiation of Acidic and Non-Acidic Tundra via Portable X-ray Fluorescence (PXRF) Spectrometry 被引量:4
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作者 Somsubhra CHAKRABORTY David C. WEINDORF +6 位作者 GARY J. MICHAELSON Chien Lu PING Ashok CHOUDHURY Tarek KANDAKJI Autumn ACREE Akriti SHARMA WANG Dandan 《Pedosphere》 SCIE CAS CSCD 2016年第4期549-560,共12页
Frozen soils or those with permafrost cover large areas of the earth's surface and support unique vegetative ecosystems. Plants growing in such harsh conditions have adapted to small niches, which allow them to su... Frozen soils or those with permafrost cover large areas of the earth's surface and support unique vegetative ecosystems. Plants growing in such harsh conditions have adapted to small niches, which allow them to survive. In northern Alaska, USA, both moist acidic and non-acidic tundra occur, yet determination of frozen soil p Hs currently requires thawing of the soil so that electrometric pH methods can be utilized. Contrariwise, a portable X-ray fluorescence(PXRF) spectrometer was used in this study to assess elemental abundances and relate those characteristics to soil pH through predictive multiple linear regressions. Two operational modes, Soil Mode and Geochem Mode, were utilized to scan frozen soils in-situ and under laboratory conditions, respectively, after soil samples were dried and ground. Results showed that lab scanning produced optimal results with adjusted coefficient of determination(R^2) of 0.88 and 0.33 and root mean squared errors(RMSEs) of 0.87 and 0.34 between elemental data and lab-determined pH for Soil Mode and Geochem Mode, respectively. Even though the presence of ice attenuated fluoresced radiation under field conditions, adjusted R^2 and RMSEs between the datasets still provided reasonable model generalization(e.g., 0.73 and 0.49 for field Geochem Mode). Principal component analysis qualitatively separated multiple sampling sites based on elemental data provided by PXRF, reflecting differences in the chemical composition of the soils studied. Summarily, PXRF can be used for in-situ determination of soil pH in arctic environments without the need for sample modification and thawing. Furthermore, use of PXRF for determination of soil pH may provide higher sample throughput than traditional eletrometric-based methods, while generating elemental data useful for the prediction of multiple soil parameters. 展开更多
关键词 frozen soil Gelisols Geochem Mode proximal sensing Soil Mode soil pH determination
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Influence of Ice on Soil Elemental Characterization via Portable X-Ray Fluorescence Spectrometry 被引量:4
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作者 D.C.WEINDORF N.BAKR +6 位作者 Y.ZHU A.MCWHIRT C.L.PING G.MICHAELSON C.NELSON K.SHOOK S.NUSS 《Pedosphere》 SCIE CAS CSCD 2014年第1期1-12,共12页
Field portable X-ray fluorescence (PXRF) spectrometry has become an increasingly popular technique for in-situ elemental characterization of soils. The technique is fast, portable, and accurate, requiring minimal sa... Field portable X-ray fluorescence (PXRF) spectrometry has become an increasingly popular technique for in-situ elemental characterization of soils. The technique is fast, portable, and accurate, requiring minimal sample preparation and no consumables. However, soil moisture 〉 20% has been known to cause fluorescence denudation and error in elemental reporting and few studies have evaluated the presence of soil moisture in solid form as ice. Gelisols (USDA Soil Taxonomy), permafrost-affected soils, cover a large amount of the land surface in the northern and southern hemispheres. Thus, the applicability of PXRF in those areas requires further investigation. PXRF was used to scan the elemental composition (Ba, Ca, Cr, Fe, K, Mn, Pb, Rb, Sr, Ti, Zn, and Zr) of 13 pedons in central and northern Alaska, USA. Four types of scans were completed: 1) in-situ frozen soil, 2) re-frozen soil in the laboratory, 3) melted soil/water mixture in the laboratory, and 4) moisture-corrected soil. All were then compared to oven dry soil scans. Results showed that the majority of PXRF readings from in-situ, re-frozen, and melted samples were significantly underestimated, compared to the readings on oven dry samples, owing to the interference expected by moisture. However, when the moisture contents were divided into 〉 40% and 〈 40〈 groups, the PXRF readings under different scanning conditions performed better in the group with 〈 40% moisture contents. Most elements of the scans on the melted samples with 〈 40% moisture contents acceptably compared to those of the dry samples, with R2 values ranging from 0.446 (Mn) to 0.930 (St). However, underestimation of the melted samples was still quite apparent. Moisture-corrected sample PXRF readings provided the best correlation to those of the dry, ground samples as indicated by higher R2 values, lower root mean square errors (RMSEs), and slopes closer to 1 in linear regression equations. However, the in-situ (frozen) sample scans did not differ appreciably from the melted sample scans in their correlations to dry sample scans in terms of R2 values (0.81 vs. 0.88), RMSEs (1.06 vs. 0.85), and slopes (0.88 vs. 0.92). Notably, all of those relationships improved for the group with moisture contents 〈 40%. 展开更多
关键词 Gelisols MOISTURE PERMAFROST proximal sensing regression
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The distribution and variation of elements in sediments off the Huanghe (Yellow) River mouth 被引量:3
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作者 乔淑卿 石学法 +4 位作者 高晶晶 刘焱光 杨刚 朱爱美 王昆山 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第4期876-885,共10页
Surface sediment samples collected off the Huanghe (Yellow) River mouth during the period 2007-2009 were analyzed for major and trace element concentrations. Concentrations of 16 elements were measured using X-ray f... Surface sediment samples collected off the Huanghe (Yellow) River mouth during the period 2007-2009 were analyzed for major and trace element concentrations. Concentrations of 16 elements were measured using X-ray fluorescence spectrometry. Results demonstrate that sediment grain size is the dominant factor controlling the spatial variations of elemental concentrations. Correlation and cluster analyses allowed classification of the study area into four geochemical regions: Regions Ⅰ and Ⅲare characterized by high concentrations ofAl2O3, Fe2O3, MgO, Na2O, K2O, Cr, Cu, Mn, Ni, Pb, V, and Zn, and contain fine-grained sediments with mean grain size (Mz)〈22 μm; and; Regions Ⅱ and Ⅳcontain mostly coarse-grained sediments, and are characterized by high concentrations of SiO2, Na2O, and Zr. The sediment entering the sea from the Huanghe River and its tributaries is enriched in Ca. Thus, the Ca/Al ratio was used as an indicator of the proportion of sediments in the study area that originated from the Huanghe River. Ca/Al ratios decrease from Regions Ⅰ and Ⅱ(located in the nearshore zone of the Huanghe River delta) to Regions Ⅲand Ⅳ(distributed in the offshore zone of the northern Huanghe River delta, southern and southeastern Laizhou Bay area). 展开更多
关键词 Huanghe (Yellow) River Bohai Sea major and trace elements grain size heavy metals
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