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1.
For the Element2 (a relatively new high-sensitivity magnetic sector ICP MS), we have studied spectral interferences from barium arising as a result of polyatomic barium ions, which have a considerable effect on the intensity of lines for rare-earth isotopes. We have shown that the parameters characterizing the interferences (the ratios of the signals from oxygen-containing, chlorine-containing, and fluorine-containing BaX+ ions to the Ba+ signal, and the apparent rare-earth concentrations Capp j resulting when overlap from polyatomic Ba occurs) are higher for the Element2 than for a quadrupole instrument (PQ2+). However, it is possible to solve many spectral overlap problems when using the Element2 by using the medium-resolution (MR) or high-resolution (HR) modes. We have estimated the resolutions needed to completely separate the masses of the polyatomic barium ions and the rare-earth isotopes in the spectrum. For cases when it is impossible to use the high-resolution mode due to the ∼100-fold decrease in sensitivity, we recommend preliminary separation of Ba from the rare earths. In this work, we have used extraction chromatography to determine low rare-earth concentration levels in Lake Baikal water. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 6, pp. 813–818, November–December, 2006.  相似文献   

2.
介绍了凝胶电泳(GE)和激光剥蚀-电感耦合等离子体质谱(LA-ICP-MS)联用测定蛋白质中微量元素的方法,对蛋白质分离、凝胶处理,包括染色及干燥,和检测过程中的定量校正等技术问题做了详述,并综述了LA-ICP-MS在硒蛋白、磷酸化蛋白及金属蛋白分析中的应用,指出了这种方法在蛋白质中微量元素检测中存在的问题和发展方向。  相似文献   

3.
激光剥蚀-电感耦合等离子体质谱测定植物样品中的元素   总被引:2,自引:0,他引:2  
Wang Q  Zhang W  Wang LY  Liu YS  Hu SH  Hu ZC 《光谱学与光谱分析》2011,31(12):3379-3383
采用193 nm准分子激光剥蚀-电感耦合等离子体质谱(LA-ICP-MS)对标准植物粉末样品(GBW07602-GBW07603灌木枝叶、GBW07604杨树叶、GBW07605茶叶、GBW08514烟草)中13种元素(Li,B,Na,Mg,Al,K,Ca,Cr,Mn,Fe,Ni,Cu,Ba)进行定量测试.向植物粉末样...  相似文献   

4.
Using different types of devices, we have performed an experimental study of matrix ionization effects manifesting themselves in the method of mass spectrometry with an inductively coupled plasma. Basic laws governing these effects have been established. The composition of the analytical zone of the plasma and possible attenuation of the signal from the analyte on introduction of a matrix element due to processes occurring in the plasma and in the ion beam have been determined theoretically. A high degree of coincidence between experimental and calculated results is shown. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 5, pp. 768–774, September–October, 1998.  相似文献   

5.
徐静阳  方少波  周婧 《物理学报》2019,68(6):68701-068701
近年来,依赖于先进光源的化学成像技术迅速发展,极大提高了痕量检测的准确性,在公共安全、环境、食品、医药、考古等领域具有重要的实用价值.在痕量检测中,通过将成像技术与光谱测量技术、质谱技术等相结合,能够同时获取检验对象的物质组成和二维图像信息,不仅可以揭示材料表面的痕量物质成分及其分布,还可以在提高检验灵敏度的情况下,减少甚至避免传统检测手段所需要的特殊显现剂,因此与其他检验方法具有良好的兼容性.本文以指纹检验这一典型的痕量检测问题为例,阐述基于光谱和质谱成像技术的化学成像方法在痕量检测领域中的应用,从定向针对特定组分的化学成像和非定向的直接化学成像两个方面,综述了在指纹显现或显现增强中获得应用的主要成像手段,包括可见-近红外成像、红外成像、拉曼成像、质谱成像等.  相似文献   

6.
ABSTRACT

A novel method, based on extraction induced by emulsion breaking, is proposed for rapid simultaneous determination of iron, manganese, copper, and zinc in jet fuel by inductively coupled plasma-mass spectrometry. Several parameters affecting the extraction efficiency were investigated including the concentrations of nitric acid and emulsifying agents, centrifugal speed, and extraction time. The limits of detection for iron, manganese, copper, and zinc were 0.116, 0.028, 0.06, and 0.085 µg L?1, respectively. The accuracy of the method was tested by the analysis of spiked samples (recovery percentages between 90% and 107% were observed) and by comparison with a well-established method.  相似文献   

7.
Abstract

Atomic spectrometry and atomic mass spectrometric (MS) techniques have been playing crucial roles in the field of biosciences. They detect elements with relatively high sensitivities and are thus applicable to a wide range of analytical targets. In the past decade, determination of bio-relevant metallic elements continues to be of interest, while particularly noteworthy are methods developed for small molecules, peptides, proteins, nucleic acids and even cells that well exploited the bio-analytical strengths of atomic spectrometry and atomic MS, either in a direct or indirect manner. Quantitation, as well as speciation and imaging analyses are all involved. The present review aims to assimilate recent advances in bio-analysis utilizing atomic spectrometry and atomic MS, primarily covering the period of 2013–2018, in an attempt to provide readers insight into the developing trends of this research frontier. Followed by concluding remarks and perspectives, the applications are divided into the following four catalogs: (i) toxicologically important metal-containing species, with an emphasis on quantitative and imaging analysis; (ii) quantitation of biomolecules using naturally occurring heteroatoms; (iii) exogenous metal ion or nanoparticle tagging-based strategies in bioassays; and (iv) label-free detection of biomolecules.  相似文献   

8.
A systematic approach is proposed to evaluate microwave-assisted digestion in a single reaction chamber for the simultaneous determination of elements in the mineral fertilizer and raw material by inductively coupled plasma optical emission spectrometry. A reference material was digested using 12 acid mixtures containing nitric, hydrochloric, orthophosphoric, hydrofluoric or boric acid. Principal components analysis was applied for data treatment. Three digestion procedures based on diluted acids exhibited the most accurate results, with relative errors for reference values ranging from ?15% to +?9%. Limits of quantification were in the range of 0.2?mg cadmium kg?1 up to 1000?mg aluminum kg?1.  相似文献   

9.
The ratio of the magnesium ion to atom signals with wavelengths of 280.270 and 285.213 nm, respectively, is frequently employed to estimate plasma robustness in inductively coupled plasma optical emission spectrometry. To guarantee a rigorous and accurate calculation of this indicator of the plasma condition, a correction for the difference in the response of the instrument at the two wavelengths of magnesium has been frequently applied. However, the literature reviewed shows inconsistencies in the values of the correction factor used. Also it is notable the lack of information concerning the procedures to calculate such correction factor.

In this paper, we propose a simple method for the best estimate of the correction factor from an appropriate measurement of the magnesium atomic and ion background signals, when a blank solution, contaminated by magnesium, is nebulized. We proved that a bad selection of the wavelengths used for background signal estimation can underestimate the correction factor up to a 56%.  相似文献   

10.
吕玲  龚欣  郝跃 《物理学报》2008,57(2):1128-1132
研究了p-GaN材料经感应耦合等离子体(ICP)刻蚀后的表面特性,并用不同的方法对刻蚀表面进行处理.利用原子力显微镜(AFM)和X射线光电子能谱(XPS)对刻蚀样品进行分析,并在样品表面制作Ni/Au电极,进行欧姆接触特性的测试.实验结果表明了NaOH溶液处理表面对改善材料表面和欧姆接触特性是比较有效的. 关键词: GaN 感应耦合等离子刻蚀 表面处理 欧姆接触  相似文献   

11.
Abstract

An inductively coupled plasma mass spectrometer method for estimating trace elements in tree nut oils has been developed which employs microwave digestion equipped with high pressure subassembly. Residual carbon content and residual acidity were determined to evaluate the efficiency of digestion. The best digestion efficiency was obtained using Easyprep? system with 0.5?g of oil, 4?mL concentrated nitric acid, and 2?mL hydrogen peroxide, and a final temperature of 235?°C. Residual carbon content and residual acidity were estimated as 1.7% (corresponding to 852?mg L?1 of carbon in sample solution) and 7.5%, respectively, and recovery values ranged from 90.7% to 107.7%. Whereas, only 0.2?g of oil could be digested through conventional microwave system with 5?mL concentrated nitric acid and 2?mL hydrogen peroxide at 205?°C (residual carbon content?=?3.2%). The developed method has been applied to determine nine trace elements (Cr, Mn, Fe, Ni, Cu, As, Zn, Cd, and Pb) in different categories of tree nut oils, and high content of Fe, Mn, and Zn were found in some of those oils. To the best of our knowledge, the present investigation is the first attempt to analyze trace elements in different categories of tree nut oils consumed in China.  相似文献   

12.
ICP-MS测定中草药狼毒中稀土和微量元素   总被引:3,自引:3,他引:0  
研究了电感耦合等离子体质谱法(ICP-MS)测定中草药狼毒中稀土和微量元素的方法,样品处理通过低温灰化方法与硝酸-过氧化氢消解方法比较,实验确认微量元素采用低温灰化法制备样品, 稀土元素采用酸消化法制备样品,可以满足该方法检测要求,具有测试方法准确、快速等优点。 方法的准确度在1.21%~15.15%, 精密度在0.38%~8.54%之间。 该方法完全可以满足中草药样品中稀土和微量元素检测要求。  相似文献   

13.
Abstract

The application of laser ablation inductively plasma mass spectrometry (LA‐ICP‐MS) to the determination of major, minor, and trace elements as well as isotope‐ratio measurements offers superior technology for direct solid sampling in analytical chemistry. The advantages of LA‐ICP‐MS include direct analysis of solids; no chemical dissolution is necessary, reduced risk of contamination, analysis of small sample mass, and determination of spatial distributions of elemental compositions. This review aims to summarize recent research to apply LA‐ICP‐MS, primarily in the field of environmental chemistry. Experimental systems, fractionation, calibration procedures, figures of merit, and new applications are discussed. Selected applications highlighting LA‐ICP‐MS are presented.  相似文献   

14.
ABSTRACT

A closed-vessel microwave-digestion method was developed for the determination of trace amounts of Be, V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Mo, Cd, Sb, Ba, Tl, and Pb by inductively coupled plasma mass spectrometry and Hg by cold-vapor atomic absorption spectrometry in cigarette tobacco samples. In order to gauge the effectiveness of the digestion procedure, recovery studies were conducted using solutions prepared from National Institute of Standards and Technology Standard Reference Material 1573a Trace Elements in Tomato Leaves and Polish Certified Reference Material Virginia Tobacco Leaves. Limits of detection were below 1 µg g?1 for all elements studied. Samples from two genuine-brand and three counterfeit packs were analyzed. The mean amounts of Be, As, Mo, Cd, Sb, Tl, Pb, and Hg were higher in counterfeit cigarettes, while the amounts of V, Cr, Mn, Co, Cu, Zn, Se, and Ba were comparable among legal and counterfeit cigarettes; the amount of Ni was higher in the legal cigarettes. Evaluation of Be, As, Mo, Cd, Sb, Tl, Pb, and Hg with their potential hazards for smokers is briefly discussed.  相似文献   

15.
The concentrations of 14 elements in Lycium barbarum L. leaves collected from the Qaidam basin (China) were determined by inductively coupled plasma mass spectrometry after microwave assisted digestion. This work presents two goals: (1) to determine 14 elements in L. barbarum leaves; (2) to examine the relationship between elements using correlation analysis, principal component analysis, and cluster analysis. The accuracy and precision were verified against a GBW07605 Tea Leaves certified reference material. The results demonstrated that the method was reliable, reproducible, and suitable for determination of the concentrations of trace elements in L. barbarum leaves. Correlation analysis showed that aluminum–copper, arsenic–zinc, manganese–selenium, and chromium–iron have medium correlation coefficients. Principal component loading for L. barbarum leaves extracted seven components explained about 85% of the total variance. Cluster analysis depicts four clusters: (1) arsenic and titanium; (2) calcium, magnesium, manganese, selenium, and zinc; (3) cobalt, iron, and molybdenum; (4) aluminum, copper, and chromium.  相似文献   

16.
A method of ultrasound-assisted digestion followed by inductively coupled plasma optical emission spectrometry (ICP-OES) used for the determination of trace element (chromium, copper, lead, nickel, vanadium and zinc) concentrations in fly ash samples was developed. All the measurements were performed in robust plasma conditions. Ultrasound-assisted digestion procedures using digestion solutions of aqua regia and hydrofluoric acid (HF) resulted in recovery rates of over 80% for all the analyte elements. Ultrasound-assisted two-step digestion with digestion solutions of 6 mL of HNO3 (Step 1) and 3 mL of HNO3 + 3 mL of HF (Step 2) resulted in recovery rates of over 92% for all the analyte elements with one exception, chromium, which had a recovery of about 85%. The analysis of SRM 1633b showed that the two-step ultrasound-assisted digestion method developed resulted in chromium, copper, nickel and zinc concentrations higher than the microwave digestion method standardized by the United States Environmental Protection Agency (USEPA method 3052). This is the very first time when a digestion method using ultrasound resulted in higher efficiency than microwave (USEPA method 3052) for chromium and nickel in very hard to dissolve samples. The major advantages of the ultrasound-assisted digestion over microwave digestion is the high treatment rate (about 30 samples simultaneously with a sonication time of 18 min) and the possibility to use new sample vessels without a significant increase in costs.  相似文献   

17.
The nonlinear ion acoustic wave propagation in a strongly coupled plasma composed of ions and trapped electrons has been investigated. The reductive perturbation method is employed to derive a modified Korteweg–de Vries–Burgers (mKdV–Burgers) equation. To solve this equation in case of dissipative system, the tangent hyperbolic method is used, and a shock wave solution is obtained. Numerical investigations show that, the ion acoustic waves are significantly modified by the effect of polarization force, the trapped electrons and the viscosity coefficients. Applying the bifurcation theory to the dynamical system of the derived mKdV–Burgers equation, the phase portraits of the traveling wave solutions of both of dissipative and non-dissipative systems are analyzed. The present results could be helpful for a better understanding of the waves nonlinear propagation in a strongly coupled plasma, which can be produced by photoionizing laser-cooled and trapped electrons [1], and also in neutron stars or white dwarfs interior.  相似文献   

18.
ICP-MS测定三种抗肿瘤中成药中铅镉汞砷含量   总被引:9,自引:0,他引:9  
采用电感耦合等离子体-质谱(ICP-MS)法测定了三种抗肿瘤中成药(金克槐耳、华蟾素和复方苦参)中四种元素铅、镉、汞、砷的含量。结果显示,铅、镉、汞、砷四种元素在三种抗肿瘤中成药中的含量较低,均符合东南亚进口标准。其中金克槐耳中汞和砷含量略高于美国FAD药品与功能性食品要求标准,但仍符合其他标准。电感耦合等离子体-质谱法是测定中成药中铅、镉、汞、砷快速、准确的方法。  相似文献   

19.
The Maoniuping rare earth elements deposit is the second largest rare earth elements deposit in China, and the third largest in the world. A sediment core was collected from the river floodplain downstream from the Maoniuping rare earth elements mining area (Sichuan Province, China) to reconstruct the cadmium contamination history and trace its contamination source. Based on lead-210 (210Pb) dating by gamma ray spectrometry and elements determination with inductively coupled plasma mass spectrometry of the sediment core, it was found that the cadmium accumulation rate of the flood plain increased from 0.16 to 2.22 µg cm?2 yr?1 over the past 100 years. Combining aspects of time, space, and element composition information, it is proved that the exploitation of Maoniuping rare earth elements deposit was the main reason for the increase. Moreover, to evaluate the mobility and availability of cadmium in the sediment core, the modified European Communities Bureau of Reference sequential extraction procedure in combination with inductively coupled plasma mass spectrometry was applied. Risk assessment code was used to further assess the environmental risk of cadmium in the sediment. It was found that the environmental risk from cadmium was high in the surface of the sediments. The results from gamma ray spectrometric and mass spectrometric methods may provide important information for the control and remedy of cadmium-related pollution areas.  相似文献   

20.
The accurate ultra-trace analysis of six fluorobenzoic acids (FBAs) via isotope dilution gas chromatography mass spectrometry through their deuterated analogues is described. North Sea reservoir and ground water samples were spiked with six deuterated FBAs (dFBAs), enriched using solid-phase extraction (SPE) and analysed using GC/MS after derivatisation with BF 3· MeOH. All FBAs were enriched and determined simultaneously. SPE allowed a 250-fold enrichment of the acids if 100 mL of sample volume was used. The method enables the determination of FBAs down to the range of 8–37 ng L ?1 with recoveries between 66 % and 85 %. It uses low amounts of chemicals and is adaptable to larger and smaller sample volumes.  相似文献   

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