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Sample records for atomic absorption faa

  1. Speciation determination of chromium(III) and (VI) using preconcentration cloud point extraction with flame atomic absorption spectrometry (FAAS)

    Energy Technology Data Exchange (ETDEWEB)

    Kiran, K. [Department of Environmental Sciences, S.V. University, Tirupati, 517502 A.P. (India); Kumar, K. Suresh; Prasad, B.; Suvardhan, K. [Department of Chemistry, S. V. University, Tirupati, 517502 A.P. (India); Lekkala, Ramesh Babu [Department of Environmental Sciences, S.V. University, Tirupati, 517502 A.P. (India); Janardhanam, K. [Department of Environmental Sciences, S.V. University, Tirupati, 517502 A.P. (India)], E-mail: Kandukurijanardhanam@gmail.com

    2008-02-11

    bis-[2-Hydroxy-1-naphthaldehyde] thiourea was synthesized and preconcentration cloud point extraction (CPE) for speciation determination of chromium(III) and (VI) in various environmental samples with flame atomic absorption spectrometry (FAAS) has been developed. Chromium(III) complexes with bis-[2-hydroxynaphthaldehyde] thiourea is subsequently entrapped in the surfactant micelles. After complexation of chromium(III) with reagent, the analyte was quantitatively extracted to the surfactant-rich phase in the non-ionic surfactant Triton X-100 after centrifugation. The effect of pH, concentration of chelating agent, surfactant, equilibration temperature and time on CPE was studied. The relative standard deviation was 2.13% and the limits of detection were around 0.18 {mu}g L{sup -1}.

  2. Determination of Fe Content of Some Food Items by Flame Atomic Absorption Spectroscopy (FAAS): A Guided-Inquiry Learning Experience in Instrumental Analysis Laboratory

    Science.gov (United States)

    Fakayode, Sayo O.; King, Angela G.; Yakubu, Mamudu; Mohammed, Abdul K.; Pollard, David A.

    2012-01-01

    This article presents a guided-inquiry (GI) hands-on determination of Fe in food samples including plantains, spinach, lima beans, oatmeal, Frosted Flakes cereal (generic), tilapia fish, and chicken using flame atomic absorption spectroscopy (FAAS). The utility of the GI experiment, which is part of an instrumental analysis laboratory course,…

  3. Rapid and simultaneous determination of essential minerals and trace elements in human milk by improved flame atomic absorption spectroscopy (FAAS) with microwave digestion.

    Science.gov (United States)

    Luo, Yang; Zhang, Bo; Chen, Ming; Wang, Jue; Zhang, Xue; Gao, Wei-Yin; Huang, Jun-Fu; Fu, Wei-Ling

    2010-09-08

    A method for the simultaneous and economical determination of many trace elements in human milk is developed. Two multi-element hollow cathode lamps (HCLs) were used instead of single-element HCLs to improve the sample throughput of flame atomic absorption spectroscopy (FAAS). The microwave digestion of milk is optimized prior to detection, and the performance characteristics of the improved analysis method are identified. Clinical samples are detected by both FAAS and inductively coupled plasma-optical emission spectroscopy (ICP-OES) for methodology evaluation. Results reveal that the proposed FAAS with multi-element HCLs could determine six essential minerals and trace elements within 15 min. This method provides a linear analytical range of 0.01-10 mg L(-1). For Ca, Cu, Fe, Mg, Mn, and Zn, the limits of determination are 1.5, 3, 1.8, 2.2, 2.1, and 1.3 microg L(-1), respectively. The mean relative standard deviations (RSDs) of intra- and interassays are lower than 7%. Excellent operational characteristics of rapidity, simplicity, and economy make the proposed method a promising one for the quantification of trace elements in human milk in clinics of underdeveloped areas.

  4. Combined discrete nebulization and microextraction process for molybdenum determination by flame atomic absorption spectrometry (FAAS); Avaliacao da combinacao da nebulizacao discreta e processos de microextracao aplicados a determinacao de molibdenio por espectrometria de absorcao atomica com chama (FAAS)

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    Oviedo, Jenny A.; Jesus, Amanda M.D. de; Fialho, Lucimar L.; Pereira-Filho, Edenir R., E-mail: erpf@ufscar.br [Universidade Federal de Sao Carlos (UFSCar), SP (Brazil). Departamento de Quimica

    2014-04-15

    Simple and sensitive procedures for the extraction/preconcentration of molybdenum based on vortex-assisted solidified floating organic drop microextraction (VA-SFODME) and cloud point combined with flame absorption atomic spectrometry (FAAS) and discrete nebulization were developed. The influence of the discrete nebulization on the sensitivity of the molybdenum preconcentration processes was studied. An injection volume of 200 μ resulted in a lower relative standard deviation with both preconcentration procedures. Enrichment factors of 31 and 67 and limits of detection of 25 and 5 μ L{sup -1} were obtained for cloud point and VA-SFODME, respectively. The developed procedures were applied to the determination of Mo in mineral water and multivitamin samples. (author)

  5. Solvent microextraction-flame atomic absorption spectrometry (SME-FAAS) for determination of ultratrace amounts of cadmium in meat and fish samples.

    Science.gov (United States)

    Goudarzi, Nasser

    2009-02-11

    A simple, low cost and highly sensitive method based on solvent microextraction (SME) for separation/preconcentration and flame atomic absorption spectrometry (FAAS) was proposed for the determination of ultratrace amounts of cadmium in meat and fish samples. The analytical procedure involved the formation of a hydrophobic complex by mixing the analyte solution with an ammonium pyrrolidinedithiocarbamate (APDC) solution. In suitable conditions, the complex of cadmium-APDC entered the micro organic phase, and thus, separation of the analyte from the matrix was achieved. Under optimal chemical and instrumental conditions, a detection limit (3 sigma) of 0.8 ng L(-1) and an enrichment factor of 93 were achieved. The relative standard deviation for the method was found to be 2.2% for Cd. The interference effects of some anions and cations were also investigated. The developed method has been applied to the determination of trace Cd in meat and fish samples.

  6. Cloud point extraction of palladium in water samples and alloy mixtures using new synthesized reagent with flame atomic absorption spectrometry (FAAS)

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    Priya, B. Krishna [Environmental Monitoring Laboratory, Department of Chemistry, S.V. University, Tirupati 517502, AP (India); Subrahmanayam, P. [Environmental Monitoring Laboratory, Department of Chemistry, S.V. University, Tirupati 517502, AP (India); Suvardhan, K. [Environmental Monitoring Laboratory, Department of Chemistry, S.V. University, Tirupati 517502, AP (India); Kumar, K. Suresh [Environmental Monitoring Laboratory, Department of Chemistry, S.V. University, Tirupati 517502, AP (India); Rekha, D. [Environmental Monitoring Laboratory, Department of Chemistry, S.V. University, Tirupati 517502, AP (India); Rao, A. Venkata [Environmental Monitoring Laboratory, Department of Chemistry, S.V. University, Tirupati 517502, AP (India); Rao, G.C. [Environmental Monitoring Laboratory, Department of Chemistry, S.V. University, Tirupati 517502, AP (India); Chiranjeevi, P. [Environmental Monitoring Laboratory, Department of Chemistry, S.V. University, Tirupati 517502, AP (India)]. E-mail: chiranjeevipattium@gmail.com

    2007-06-01

    The present paper outlines novel, simple and sensitive method for the determination of palladium by flame atomic absorption spectrometry (FAAS) after separation and preconcentration by cloud point extraction (CPE). The cloud point methodology was successfully applied for palladium determination by using new reagent 4-(2-naphthalenyl)thiozol-2yl azo chromotropic acid (NTACA) and hydrophobic ligand Triton X-114 as chelating agent and nonionic surfactant respectively in the water samples and alloys. The following parameters such as pH, concentration of the reagent and Triton X-114, equilibrating temperature and centrifuging time were evaluated and optimized to enhance the sensitivity and extraction efficiency of the proposed method. The preconcentration factor was found to be (50-fold) for 250 ml of water sample. Under optimum condition the detection limit was found as 0.067 ng ml{sup -1} for palladium in various environmental matrices. The present method was applied for the determination of palladium in various water samples, alloys and the result shows good agreement with reported method and the recoveries are in the range of 96.7-99.4%.

  7. EVALUATION OF HEAVY METALS IN ETHANOLIC LEAF EXTRACT OF ACACIA CATECHU AS INDICATOR OF POLLUTION BY ATOMIC ABSORPTION SPECTROPHOTOMETRIC (FAAS ANALYSIS

    Directory of Open Access Journals (Sweden)

    Lakshmi.T

    2013-06-01

    Full Text Available Acacia catechu ethanolic leaf extract were selected to determine their heavy metals content and thereby to assure their safer therapeutic application. The trace and heavy metals were detected through atomic absorption spectrometry analysis. The selected medicinal plant material was procured from green chem herbal extracts, Bangalore, India and was digested with nitric acid and hydrochloric acid as specified. Absorbance was measured through atomic absorption spectrometer (AA 6030 and the concentration of different heavy metals in the plant sample was calculated. The quantitative determinations were carried out using standard calibration curve obtained by the standard solutions of different metals. The contents of heavy metals were found to be within the prescribed limit. Thus, on the basis of experimental outcome, it can be concluded that the plant material is safe and may not produce any harmful effect of metal toxicity during their therapeutic application. The investigated medicinal plants contains heavy metals such as arsenic (As, lead (Pb and mercury (Hg and cadmium (Cd, which were present within the permissible limit.

  8. A simple and fast ultrasound-assisted extraction procedure for Fe and Zn determination in milk-based infant formulas using flame atomic absorption spectrometry (FAAS).

    Science.gov (United States)

    Machado, Ignacio; Bergmann, Gabriela; Pistón, Mariela

    2016-03-01

    A simple and fast ultrasound-assisted procedure for the determination of iron and zinc in infant formulas is presented. The analytical determinations were carried out by flame atomic absorption spectrometry. Multivariate experiments were performed for optimization; in addition, a comparative study was carried out using two ultrasonic devices. A method using an ultrasonic bath was selected because several samples can be prepared simultaneously, and there is less contamination risk. Analytical precision (sr(%)) was 3.3% and 4.1% for iron and zinc, respectively. Trueness was assessed using a reference material and by comparison of the results obtained analyzing commercial samples using a reference method. The results were statistically equivalent to the certified values and in good agreement with those obtained using the reference method. The proposed method can be easily implemented in laboratories for routine analysis with the advantage of being rapid and in agreement with green chemistry.

  9. Solid-phase extraction of Mn(II), Co(II), Ni(II), Cu(II), Cd(II) and Pb(II) ions from environmental samples by flame atomic absorption spectrometry (FAAS)

    Energy Technology Data Exchange (ETDEWEB)

    Duran, Celal [Department of Chemistry, Faculty of Art and Science, Karadeniz Technical University, 61080 Trabzon (Turkey); Gundogdu, Ali [Department of Chemistry, Faculty of Art and Science, Karadeniz Technical University, 61080 Trabzon (Turkey); Bulut, Volkan Numan [Department of Chemistry, Giresun Faculty of Art and Science, Karadeniz Technical University, 28049 Giresun (Turkey); Soylak, Mustafa [Department of Chemistry, Faculty of Art and Science, Erciyes University, 38039 Kayseri (Turkey)]. E-mail: soylak@erciyes.edu.tr; Elci, Latif [Department of Chemistry, Faculty of Art and Science, Pamukkale University, 20020 Denizli (Turkey); Sentuerk, Hasan Basri [Department of Chemistry, Faculty of Art and Science, Karadeniz Technical University, 61080 Trabzon (Turkey); Tuefekci, Mehmet [Department of Chemistry, Faculty of Art and Science, Karadeniz Technical University, 61080 Trabzon (Turkey)

    2007-07-19

    A new method using a column packed with Amberlite XAD-2010 resin as a solid-phase extractant has been developed for the multi-element preconcentration of Mn(II), Co(II), Ni(II), Cu(II), Cd(II), and Pb(II) ions based on their complex formation with the sodium diethyldithiocarbamate (Na-DDTC) prior to flame atomic absorption spectrometric (FAAS) determinations. Metal complexes sorbed on the resin were eluted by 1 mol L{sup -1} HNO{sub 3} in acetone. Effects of the analytical conditions over the preconcentration yields of the metal ions, such as pH, quantity of Na-DDTC, eluent type, sample volume and flow rate, foreign ions etc. have been investigated. The limits of detection (LOD) of the analytes were found in the range 0.08-0.26 {mu}g L{sup -1}. The method was validated by analyzing three certified reference materials. The method has been applied for the determination of trace elements in some environmental samples.

  10. Determination of Calcium in Cereal with Flame Atomic Absorption Spectroscopy: An Experiment for a Quantitative Methods of Analysis Course

    Science.gov (United States)

    Bazzi, Ali; Kreuz, Bette; Fischer, Jeffrey

    2004-01-01

    An experiment for determination of calcium in cereal using two-increment standard addition method in conjunction with flame atomic absorption spectroscopy (FAAS) is demonstrated. The experiment is intended to introduce students to the principles of atomic absorption spectroscopy giving them hands on experience using quantitative methods of…

  11. [Digestion-flame atomic absorption spectroscopy].

    Science.gov (United States)

    Xu, Liang; Hu, Jian-Guo; Liu, Rui-Ping; Wang, Zhi-Min; Narenhua

    2008-01-01

    A microwave digestion-flame atomic absorption spectroscopy (FAAS) method was developed for the determination of metal elements Na, Zn, Cu, Fe, Mn, Ca and Mg in Mongolian patents. The instrument parameters for the determination were optimized, and the appropriate digestion solvent was selected. The recovery of the method was between 95.8% and 104.3%, and the RSD was between 1.6% and 4.2%. The accuracy and precision of the method was tested by comparing the values obtained from the determination of the standard sample, bush twigs and leaves (GSV-1) by this method with the reference values of GSV-1. The determination results were found to be basically consistent with the reference values. The microwave digestion technique was applied to process the samples, and the experimental results showed that compared to the traditional wet method, the present method has the merits of simplicity, saving agents, rapidness, and non-polluting. The method was accurate and reliable, and could be used to determine the contents of seven kinds of metal elements in mongolian patents.

  12. Atomic absorption spectroscopy in ion channel screening.

    Science.gov (United States)

    Stankovich, Larisa; Wicks, David; Despotovski, Sasko; Liang, Dong

    2004-10-01

    This article examines the utility of atomic absorption spectroscopy, in conjunction with cold flux assays, to ion channel screening. The multiplicity of ion channels that can be interrogated using cold flux assays and atomic absorption spectroscopy is summarized. The importance of atomic absorption spectroscopy as a screening tool is further elaborated upon by providing examples of the relevance of ion channels to various physiological processes and targeted diseases.

  13. Absorption imaging of a single atom

    Science.gov (United States)

    Streed, Erik W.; Jechow, Andreas; Norton, Benjamin G.; Kielpinski, David

    2012-07-01

    Absorption imaging has played a key role in the advancement of science from van Leeuwenhoek's discovery of red blood cells to modern observations of dust clouds in stellar nebulas and Bose-Einstein condensates. Here we show the first absorption imaging of a single atom isolated in a vacuum. The optical properties of atoms are thoroughly understood, so a single atom is an ideal system for testing the limits of absorption imaging. A single atomic ion was confined in an RF Paul trap and the absorption imaged at near wavelength resolution with a phase Fresnel lens. The observed image contrast of 3.1 (3)% is the maximum theoretically allowed for the imaging resolution of our set-up. The absorption of photons by single atoms is of immediate interest for quantum information processing. Our results also point out new opportunities in imaging of light-sensitive samples both in the optical and X-ray regimes.

  14. Optimized absorption imaging of mesoscopic atomic clouds

    Science.gov (United States)

    Muessel, Wolfgang; Strobel, Helmut; Joos, Maxime; Nicklas, Eike; Stroescu, Ion; Tomkovič, Jiří; Hume, David B.; Oberthaler, Markus K.

    2013-10-01

    We report on the optimization of high-intensity absorption imaging for small Bose-Einstein condensates. The imaging calibration exploits the linear scaling of the quantum projection noise with the mean number of atoms for a coherent spin state. After optimization for atomic clouds containing up to 300 atoms, we find an atom number resolution of atoms, mainly limited by photon shot noise and radiation pressure.

  15. EVALUATION OF HEAVY METALS CONTENT IN EDIBLE MUSHROOMS BY MICROWAVE DIGESTION AND FLAME ATOMIC ABSORPTION SPECTROMETRY

    OpenAIRE

    Cristiana Radulescu; Claudia Stihi; Valerica Gh. Cimpoca; Popescu, Ion V.; Gabriela Busuioc; Ana Irina Gheboianu

    2011-01-01

    The aim of this work was to determine the heavy metal (Cd, Cr, Ni, Pb, Mn, Zn, Fe and Cu) content of the fruiting bodies (cap and stipe) of four species (Amanita caesarea, Pleurotus ostreatus, Fistulina hepatica and Armillariella mellea) and their substrate, collected from forest sites in Dâmboviţa County, Romania. The elements were determined by Flame Atomic Absorption Spectrometry (FAAS) after microwave assisted digestion. From the same collecting point were taken n = 5 samples of young and...

  16. Absorption imaging of a single atom

    CERN Document Server

    Streed, E W; Norton, B G; Kielpinski, D

    2012-01-01

    Absorption imaging has played a key role in the advancement of science from van Leeuwenhoek's discovery of red blood cells to modern observations of dust clouds in stellar nebula. Here we show the first absorption imaging of a single atom isolated in vacuum. The simplicity of this system lets us compare our results directly to quantum theory, unlike recent work on absorption imaging of single molecules. The observed image contrast of 3.1(3)% achieved the maximum allowed by quantum theory for our setup, while the imaging resolution was on the order of the 370 nm illumination wavelength. The absorption of photons by single atoms is of immediate interest for quantum information processing (QIP). Our results also point out new opportunities in imaging of light-sensitive samples both in the optical and x-ray regimes. In particular, the dynamics of chromatin in living cells could be imaged without delivering a lethal UV dose.

  17. [Biological material sampling for atomic absorption analysis].

    Science.gov (United States)

    Makarenko, N P; Ganebnykh, E V

    2007-01-01

    The optimum conditions have been chosen for mineralization of biological material for the atomic absorption determination of toxic metals, by using a [Russian characters: see text]-01 laboratory furnace (Gefest) upon exposure to high temperature, pressure, and microwave field. The completeness of dissection of biological material by microwave mineralization is shown under the optimal conditions.

  18. Absorption of copper(II) by creosote bush (Larrea tridentata): use of atomic and x-ray absorption spectroscopy.

    Science.gov (United States)

    Gardea-Torresdey, J L; Arteaga, S; Tiemann, K J; Chianelli, R; Pingitore, N; Mackay, W

    2001-11-01

    Larrea tridentata (creosote bush), a common North American native desert shrub, exhibits the ability to take up copper(II) ions rapidly from solution. Following hydroponic studies, U.S. Environmental Protection Agency method 200.3 was used to digest the plant samples, and flame atomic absorption spectroscopy (FAAS) was used to determine the amount of copper taken up in different parts of the plant. The amount of copper(II) found within the roots, stems, and leaves was 13.8, 1.1, and 0.6 mg/g, respectively, after the creosote bush was exposed to a 63.5-ppm copper(II) solution for 48 h. When the plant was exposed to a 635-ppm copper(II) solution, the roots, stems, and leaves contained 35.0, 10.5, and 3.8 mg/g, respectively. In addition to FAAS analysis, x-ray microfluorescence (XRMF) analysis of the plant samples provided further confirmation of copper absorption by the various plant parts. X-ray absorption spectroscopy (XAS) elucidated the oxidation state of the copper absorbed by the plants. The copper(II) absorbed from solution remained as copper(II) bound to oxygen-containing ligands within the plant samples. The results of this study indicate that creosote bush may provide a useful and novel method of removing copper(II) from contaminated soils in an environmentally friendly manner.

  19. Determination of tellurium by hydride generation with in situ trapping flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Matusiewicz, H.; Krawczyk, M. [Politechn Poznanska, Poznan (Poland)

    2007-03-15

    The analytical performance of coupled hydride generation - integrated atom trap (HG-IAT) atomizer flame atomic absorption spectrometry (FAAS) system was evaluated for determination of Te in reference material (GBW 07302 Stream Sediment), coal fly ash and garlic. Tellurium, using formation of H{sub 2}Te vapors, is atomized in air-acetylene flame-heated IAT. A new design HG-IAT-FAAS hyphenated technique that would exceed the operational capabilities of existing arrangernents (a water-cooled single silica tube, double-slotted quartz tube or an 'integrated trap') was investigated. An improvement in detection limit was achieved compared with using either of the above atom trapping techniques separately. The concentration detection limit, defined as 3 times the blank standard deviation (3{sigma}), was 0.9 ng mL{sup -1} for Te. For a 2 min in situ preconcentration time (sample volume of 2 mL), sensitivity enhancement compared to flame AAS, was 222 fold, using the hydride generation atom trapping technique. The sensitivity can be further improved by increasing the collection time. The precision, expressed as RSD, was 7.0% (n = 6) for Te. The accuracy of the method was verified using a certified reference material (GBW 07302 Stream Sediment) by aqueous standard calibration curves. The measured Te contents of the reference material was in agreement with the information value. The method was successfully applied to the determination of tellurium in coal fly ash and garlic.

  20. Lead determination at ng/mL level by flame atomic absorption spectrometry using a tantalum coated slotted quartz tube atom trap.

    Science.gov (United States)

    Demirtaş, İlknur; Bakırdere, Sezgin; Ataman, O Yavuz

    2015-06-01

    Flame atomic absorption spectrometry (FAAS) still keeps its importance despite the relatively low sensitivity; because it is a simple and economical technique for determination of metals. In recent years, atom traps have been developed to increase the sensitivity of FAAS. Although the detection limit of FAAS is only at the level of µg/mL, with the use of atom traps it can reach to ng/mL. Slotted quartz tube (SQT) is one of the atom traps used to improve sensitivity. In atom trapping mode of SQT, analyte is trapped on-line in SQT for few minutes using ordinary sample aspiration, followed by the introduction of a small volume of organic solvent to effect the revolatilization and atomization of analyte species resulting in a transient signal. This system is economical, commercially available and easy to use. In this study, a sensitive analytical method was developed for the determination of lead with the help of SQT atom trapping flame atomization (SQT-AT-FAAS). 574 Fold sensitivity enhancement was obtained at a sample suction rate of 3.9 mL/min for 5.0 min trapping period with respect to FAAS. Organic solvent was selected as 40 µL of methyl isobutyl ketone (MIBK). To obtain a further sensitivity enhancement inner surface of SQT was coated with several transition metals. The best sensitivity enhancement, 1650 fold enhancement, was obtained by the Ta-coated SQT-AT-FAAS. In addition, chemical nature of Pb species trapped on quartz and Ta surface, and the chemical nature of Ta on quartz surface were investigated by X-ray photoelectron spectroscopy (XPS) and Raman Spectroscopy. Raman spectrometric results indicate that tantalum is coated on SQT surface in the form of Ta2O5. XPS studies revealed that the oxidation state of Pb in species trapped on both bare and Ta coated SQT surfaces is +2. For the accuracy check, the analyses of standard reference material were performed by use of SCP SCIENCE EnviroMAT Low (EU-L-2) and results for Pb were to be in good agreement with

  1. Various applications of Zeeman atomic absorption spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Koizumi, H.

    1978-06-01

    The application of the Zeeman effect to atomic absorption spectroscopy has been studied over the past several years. This technique has a larger area of application than conventional AAS because of its high degree of selectivity. The ZAA technique can be used for organometallic species determination by interfacing with a high-pressure liquid chromatograph. Various kinds of eluents can be directly introduced in the ZAA system; even organic solvents or high-concentration salt solutions. For example, the Co atom in the functional center of Vitamin B12 molecule was separately analyzed in the presence of much larger amounts of inorganic Co. In the ZAA technique, interference caused by direct spectral overlap can also be corrected. As a typical example, the Sb line at 217.02 nm overlaps the Pb absorption line at 217.00 nm. However, 1000 ppM of Pb did not cause any interference signal in the Sb analysis by ZAA. This is especially important in the analysis of gun powder residue that is often carried out by chemists working in the forensic field. In the determination of trace elements in matrices of unknown composition, the ZAA technique achieved highly reliable results by employing the standard addition method to correct for chemical interferences, because any nonspecific absorption or emission does not give rise to interference signals with this technique.

  2. The absorptive line shape of hadronic atoms

    CERN Document Server

    Ericson, Torleif Eric Oskar

    1977-01-01

    The exact line shape for all energies is derived analytically in the limit of negligible nuclear dimensions. The shape deviates from the Breit-Wigner form. The high-energy tail of the line has a universal shape, independent of the absorptive strength. The tails are different for different initial states, however. The integrated line strength diverges logarithmically. Renormalization of the hadron wavefunction by strong interactions leads to the usual shape near resonance and restores convergence for very large energies. The results resolve a logical inconsistency in the normal analysis of hadronic atoms and are of practical importance. It is shown that bound hadronic states (e.g. Y/sub 0/*) give natural contributions in the high energy region. Numerical illustrations are given. (6 refs).

  3. Spectral aspects of the determination of Si in organic and aqueous solutions using high-resolution continuum source or line source flame atomic absorption spectrometry

    Science.gov (United States)

    Kowalewska, Zofia; Pilarczyk, Janusz; Gościniak, Łukasz

    2016-06-01

    High-resolution continuum source flame atomic absorption spectrometry (HR-CS FAAS) was applied to reveal and investigate spectral interference in the determination of Si. An intensive structured background was observed in the analysis of both aqueous and xylene solutions containing S compounds. This background was attributed to absorption by the CS molecule formed in the N2O-C2H2 flame. The lines of the CS spectrum at least partially overlap all five of the most sensitive Si lines investigated. The 251.611 nm Si line was demonstrated to be the most advantageous. The intensity of the structured background caused by the CS molecule significantly depends on the chemical form of S in the solution and is the highest for the most-volatile CS2. The presence of O atoms in an initial S molecule can diminish the formation of CS. To overcome this S effect, various modes of baseline fitting and background correction were evaluated, including iterative background correction (IBC) and utilization of correction pixels (WRC). These modes were used either independently or in conjunction with least squares background correction (LSBC). The IBC + LSBC mode can correct the extremely strong interference caused by CS2 at an S concentration of 5% w:w in the investigated solution. However, the efficiency of this mode depends on the similarity of the processed spectra and the correction spectra in terms of intensity and in additional effects, such as a sloping baseline. In the vicinity of the Si line, three lines of V were recorded. These lines are well-separated in the HR-CS FAAS spectrum, but they could be a potential source of overcorrection when using line source flame atomic absorption spectrometry (LS FAAS). The expected signal for the 251.625 nm Fe line was not registered at 200 mg L- 1 Fe concentration in the solution, probably due to the diminished population of Fe atoms in the high-temperature flame used. The observations made using HR-CS FAAS helped to establish a "safe" level

  4. Evaluation of lithium determination in three analyzers: flame emission, flame atomic absorption spectroscopy and ion selective electrode

    Directory of Open Access Journals (Sweden)

    Mehri Aliasgharpour

    2009-10-01

    Full Text Available Background: Lithium carbonate salt has become an increasingly important substance in the treatment of manic depressive disorders, and its relatively narrow therapeutic range has caused laboratories to monitor the serum concentration carefully. In the present work we evaluated lithium measurement in 3 different analyzers. Methods & Materials: Three different analyzers including Flame Emission (FES, Flame Atomic Absorption Spectroscopy (FAAS, and Ion Selective Electrode (ISE were used. All chemicals had a grade suitable for trace metal analysis. Results: Within-day precision of CV was ≤ 1.5% for FES & FAAS, except for ISE (1.9% CV. Between-days precision of CV was less for FES than for FAAS and ISE (1.3% versus 2.2% & 2.3%. The percent recovery of added lithium in pooled patients’ serum was higher for ISE than for FASS and FES (103.4% versus 96.2% and 94.6%. We also obtained a higher average lithium concentration for patients’ serum samples (n=16 measured by ISE than for FAAS and FES (0.825±0.30 versus 0.704±0.26 & 0.735±0.19. Paired t-test results revealed a significant difference (p< 0.001 for patient sera analyzed with FAAS and ISE. Conclusion: We report higher results for ISE than the other two analyzers and conclude that the choice between the two flame methods for patients’ serum lithium determination is arbitrary and that FES analyzer is a more attractive routine alternative for lithium determination than FAAS because of its cost and ease of performance. In addition, the results obtained by ISE are precise. However, its accuracy may depend on other interfering factors.

  5. Cloud point extraction for the determination of copper in environmental samples by flame atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    Ardeshir Shokrollahi

    2008-01-01

    Full Text Available A simple cloud point extraction procedure is presented for the preconcentration of copper in various samples. After complexation by 4-hydroxy-2-mercapto-6-propylpyrimidine (PTU, copper ions are quantitatively extracted into the phase rich in Triton X-114 after centrifugation. Methanol acidified with 0.5 mol L-1 HNO3 was added to the surfactant-rich phase prior to its analysis by flame atomic absorption spectrometry (FAAS. Analytical parameters including concentrations for PTU, Triton X-114 and HNO3, bath temperature, centrifugation rate and time were optimized. The influences of the matrix ions on the recoveries of copper ions were investigated. The detection limits (3SDb/m, n=4 of 1.6 ng mL-1 along with enrichment factors of 30 for Cu were achieved. The proposed procedure was applied to the analysis of environmental samples.

  6. [Determination of thirteen metal elements in the plant Foeniculum vulgare Mill. by flame atomic absorption spectrophotometry].

    Science.gov (United States)

    Xue, Guo-qing; Liu, Qing; Han, Yu-qi; Wei, Hui-guang; Dong, Ting

    2006-10-01

    The objective of the paper is to determine the amount of metal elements of Na, K, Mg, Ca, Cu, Zn, Mn, Fe, Co, Ni, Cd, Cr and Pb in the planted Foeniculum vulgare Mill. by flame atomic absorption spectrophotometry (FAAS), after the cinefaction and the digestion with HNO3-HClO4 (phi 4:1) at 90-95 degrees C and normal pressure. The optimum parameters of FAAS and the effects of solution medium on the results were investigated. The analytical results show that the amount of Na, K, Mg, Ca, Mn, Fe, Cu, Zn and Pb was 1508.7, 27653.0, 2036.0, 4848.1, 24.8, 323.5, 15.2, 23.7 and 10.8 microg x g(-1), respectively, and that of Co, Ni, Cd and Cr was not checked out in the samples. The recovery of standard addition is 97.45%-102.50%, the relative standard deviation (n=9) was 0.34%-2.77%. The characteristic method is quick, simple and convenient and the results are satisfactory.

  7. Preconcentration of Copper Using 1,5-Diphenyl Carbazide as the Complexing Agent via Dispersive Liquid-Liquid Microextraction and Determination by Flame Atomic Absorption Spectrometry

    OpenAIRE

    Reyhaneh Rahnama; Elaheh Shafiei; Mohammad Reza Jamali

    2013-01-01

    We report a simple and sensitive microextraction system for the preconcentration and determination of Cu (II) by flame atomic absorption spectrometry (FAAS). Dispersive liquid-liquid microextraction is a modified solvent extraction method and its acceptor-to-donor phase ratio is greatly reduced compared with other methods. In the proposed approach, 1,5-diphenyl carbazide (DPC) was used as a copper ion selective complexing agent. Several variables such as the extraction and dispersive solvent ...

  8. Visualizing the Solute Vaporization Interference in Flame Atomic Absorption Spectroscopy

    Science.gov (United States)

    Dockery, Christopher R.; Blew, Michael J.; Goode, Scott R.

    2008-01-01

    Every day, tens of thousands of chemists use analytical atomic spectroscopy in their work, often without knowledge of possible interferences. We present a unique approach to study these interferences by using modern response surface methods to visualize an interference in which aluminum depresses the calcium atomic absorption signal. Calcium…

  9. Two-dimensional atom localization via probe absorption in a four-level atomic system

    Institute of Scientific and Technical Information of China (English)

    Wang Zhi-Ping; Ge Qiang; Ruan Yu-Hua; Yu Ben-Li

    2013-01-01

    We have investigated the two-dimensional (2D) atom localization via probe absorption in a coherently driven fourlevel atomic system by means of a radio-frequency field driving a hyperfine transition.It is found that the detecting probability and precision of 2D atom localization can be significantly improved via adjusting the system parameters.As a result,our scheme may be helpful in laser cooling or the atom nano-lithography via atom localization.

  10. Graviton Emission and Absorption by Atomic Hydrogen

    CERN Document Server

    Rothman, S B T

    2006-01-01

    Graviton absorption cross sections and emission rates for hydrogen are calculated by both semi-classical and field theoretic methods. We point out several mistakes in the literature concerning spontaneous emission of gravitons and related phenomena, some of which are due to a subtle issue concerning gauge invariance of the linearized interaction Hamiltonian.

  11. Heralded single photon absorption by a single atom

    CERN Document Server

    Piro, Nicolas; Schuck, Carsten; Almendros, Marc; Huwer, Jan; Ghosh, Joyee; Haase, Albrecht; Hennrich, Markus; Dubin, Francois; Eschner, Jürgen

    2010-01-01

    The emission and absorption of single photons by single atomic particles is a fundamental limit of matter-light interaction, manifesting its quantum mechanical nature. At the same time, as a controlled process it is a key enabling tool for quantum technologies, such as quantum optical information technology [1, 2] and quantum metrology [3, 4, 5, 6]. Controlling both emission and absorption will allow implementing quantum networking scenarios [1, 7, 8, 9], where photonic communication of quantum information is interfaced with its local processing in atoms. In studies of single-photon emission, recent progress includes control of the shape, bandwidth, frequency, and polarization of single-photon sources [10, 11, 12, 13, 14, 15, 16, 17], and the demonstration of atom-photon entanglement [18, 19, 20]. Controlled absorption of a single photon by a single atom is much less investigated; proposals exist but only very preliminary steps have been taken experimentally such as detecting the attenuation and phase shift o...

  12. Comparison of serum copper determination by colorimetric and atomic absorption spectrometric methods in seven different laboratories. The S.F.B.C. (Société Française de Biologie Clinique) Trace Element Group.

    Science.gov (United States)

    Arnaud, J; Chappuis, P; Zawislak, R; Houot, O; Jaudon, M C; Bienvenu, F; Bureau, F

    1993-02-01

    An interlaboratory collaborative trial was conducted on the determination of serum copper using two different methods, based on colorimetry (test combination Copper, Boehringer Mannheim, Mannheim, Germany) and flame atomic absorption spectrometry (FAAS). The general performance of the colorimetric method was below that of FAAS, except for sensitivity and linear range, as assessed by detection limit (0.44 versus 1.32 mumol/L) and upper limit of linearity (150 versus 50 mumol/L). The range of the between-run CVs and the recovery of standard additions were, respectively, 2.3-11.9% and 92-127% for the colorimetric method and 1.1-6.0% and 93-101% for the FAAS method. Interferences were minimal with both methods. The two techniques correlated satisfactorily (the correlation coefficients ranged from 0.945-0.970 among laboratories) but the colorimetric assay exhibited slightly higher results than the FAAS method. Each method was transferable among laboratories.

  13. Principles and calibration of collinear photofragmentation and atomic absorption spectroscopy

    Science.gov (United States)

    Sorvajärvi, Tapio; Toivonen, Juha

    2014-06-01

    The kinetics of signal formation in collinear photofragmentation and atomic absorption spectroscopy (CPFAAS) are discussed, and theoretical equations describing the relation between the concentration of the target molecule and the detected atomic absorption in case of pure and impure samples are derived. The validity of the equation for pure samples is studied experimentally by comparing measured target molecule concentrations to concentrations determined using two other independent techniques. Our study shows that CPFAAS is capable of measuring target molecule concentrations from parts per billion (ppb) to hundreds of parts per million (ppm) in microsecond timescale. Moreover, the possibility to extend the dynamic range to cover eight orders of magnitude with a proper selection of fragmentation light source is discussed. The maximum deviation between the CPFAAS technique and a reference measurement technique is found to be less than 5 %. In this study, potassium chloride vapor and atomic potassium are used as a target molecule and a probed atom, respectively.

  14. Electromagnetically induced absorption in metastable 83Kr atoms

    CERN Document Server

    Kale, Y B; Mishra, S R; Singh, S; Rawat, H S

    2015-01-01

    We report electromagnetically induced absorption (EIA) resonances of sub-natural linewidth (FWHM) in metastable noble gas 83Kr* atoms using degenerate two level schemes (DTLSs). This is the first observation of EIA effect in a metastable noble gas atoms. Using these spectrally narrow EIA signals obtained corresponding to the closed hyperfine transition from 4p55s[3/2]2 to 4p55p[5/2]3 hyperfine manifolds of 83Kr* atoms, we have measured the Lande's g-factor (gF) for the lower level (F = 13/2) of the closed transition accurately with small applied magnetic fields of few Gauss.

  15. Atomic Absorption Spectroscopy. The Present and the Future.

    Science.gov (United States)

    Slavin, Walter

    1982-01-01

    The status of current techniques and methods of atomic absorption (AA) spectroscopy (flame, hybrid, and furnace AA) is discussed, including limitations. Technological opportunities and how they may be used in AA are also discussed, focusing on automation, microprocessors, continuum AA, hybrid analyses, and others. (Author/JN)

  16. Developing a Transdisciplinary Teaching Implement for Atomic Absorption Spectroscopy

    Science.gov (United States)

    Drew, John

    2008-01-01

    In this article I explain why I wrote the set of teaching notes on Atomic Absorption Spectroscopy (AAS) and why they look the way they do. The notes were intended as a student reference to question, highlight and write over as much as they wish during an initial practical demonstration of the threshold concept being introduced, in this case…

  17. [Burner head with high sensitivity in atomic absorption spectroscopy].

    Science.gov (United States)

    Feng, X; Yang, Y

    1998-12-01

    This paper presents a burner head with gas-sample separate entrance and double access, which is used for atomic absorption spectroscopy. According to comparison and detection, the device can improve sensitivity by a factor of 1 to 5. In the meantime it has properties of high stability and resistance to interference.

  18. Precision atomic beam density characterization by diode laser absorption spectroscopy

    Science.gov (United States)

    Oxley, Paul; Wihbey, Joseph

    2016-09-01

    We provide experimental and theoretical details of a simple technique to determine absolute line-of-sight integrated atomic beam densities based on resonant laser absorption. In our experiments, a thermal lithium beam is chopped on and off while the frequency of a laser crossing the beam at right angles is scanned slowly across the resonance transition. A lock-in amplifier detects the laser absorption signal at the chop frequency from which the atomic density is determined. The accuracy of our experimental method is confirmed using the related technique of wavelength modulation spectroscopy. For beams which absorb of order 1% of the incident laser light, our measurements allow the beam density to be determined to an accuracy better than 5% and with a precision of 3% on a time scale of order 1 s. Fractional absorptions of order 10-5 are detectable on a one-minute time scale when we employ a double laser beam technique which limits laser intensity noise. For a lithium beam with a thickness of 9 mm, we have measured atomic densities as low as 5 × 104 atoms cm-3. The simplicity of our technique and the details we provide should allow our method to be easily implemented in most atomic or molecular beam apparatuses.

  19. ANALYSIS OF UNCERTAINTY MEASUREMENT IN ATOMIC ABSORPTION SPECTROPHOTOMETER

    Directory of Open Access Journals (Sweden)

    NEHA S.MAHAJAN

    2012-05-01

    Full Text Available A spectrophotometer is a photometer that can measure intensity as a function of the light source wavelength. The important features of spectrophotometers are spectral bandwidth and linear range of absorption or reflectance measurement. Atomic absorption spectroscopy (AAS is a very common technique for detecting chemical composition of elements in metal and its alloy. It is very reliable and simple to use. Quality of result (accuracy depends on the uncertainty of measurement value of the test. If uncertainty of measurement is more there may be doubt of about the final result. The final result of Atomic Absorption Spectrophotometer gets affected by the number of parameters; we should take in to account will calculating the final result. This paper deal with the methodology of evaluating the uncertainty of measurement of chemical composition using AAS. The study is useful for quality of measurement equipment and testing process.

  20. 浊点萃取-火焰原子吸收法(CPE-FAAS)测定蜂蜜中痕量锰%Determination of trace manganese in honey by cloud point extracton-flame absorption spectrometry

    Institute of Scientific and Technical Information of China (English)

    杜军良; 尤海霞; 胡杨; 王秀峰

    2013-01-01

    A new method for determination of trace manganese (Ⅱ) in honey by flame atomic absorption spectrometry combined with cloud point extraction was developed.The cloud point extraction system was based on TritonX-100 as surfactant and 8-Oxyquinoline as complexing agent.The parameters affecting cloud point extraction, including pH, extraction temperature, time, ionic strength, dosage of extraction agent and complexing agent were investigated and optimized.Under the optimum conditions, a good linear relationship was observed for manganese (Ⅱ) in the range of 100~700 ng/mL with the detection limit of 5.74 ng/mL and the relative standard deviations of 1.68% (n = 11 ).The recoveries were in the range of 97.3% ~98.6%.The method was rapid, accurate, simple and suitable to apply in the determination of manganese (Ⅱ) in honey.%研究了以8-羟基喹啉为络合剂,非离子表面活性剂TritonX-100为萃取剂的浊点萃取-火焰原子吸收光谱法(CPE-FAAS)测定蜂蜜中痕量Mn(Ⅱ)的方法.研究了pH值,平衡时间,离子强度,萃取剂用量,以及络合剂用量和共存离子干扰等对萃取效果的影响.方法线性范围为100 ~ 700 ng/mL,检出限为5.74 ng/mL,相对标准偏差为1.68% (n=11),回收率为97.3% ~98.6%.

  1. Espectrometria de absorção atômica: o caminho para determinações multi-elementares Atomic absorption spectrometry: the way for multielement determinations

    Directory of Open Access Journals (Sweden)

    Fábio Alan Carqueija Amorim

    2008-01-01

    Full Text Available This paper present an overview of way covered for the spectrometry of atomic absorption (AAS, tracing a line of the historical events in its development and its establishment as a multielement technique. Additionally, the efforts carried by through several researchers in the search for the instrumental evolution, the advances, advantages, limitations, and trends of this approach are related. Several works focusing its analytical applications are cited employing simultaneous multielement determination by flame (FAAS and/or graphite furnace (GF AAS, and fast sequential multielement determination using FAAS are reported in the present review.

  2. Determination of trace amount of cadmium using dispersive liquid-liquid microextraction-slotted quartz tube-flame atomic absorption spectrometry

    Science.gov (United States)

    Fırat, Merve; Bakırdere, Sezgin; Fındıkoğlu, Maral Selin; Kafa, Emine Betül; Yazıcı, Elif; Yolcu, Melda; Büyükpınar, Çağdaş; Chormey, Dotse Selali; Sel, Sabriye; Turak, Fatma

    2017-03-01

    This study was performed to develop a sensitive analytical method for the determination of cadmium by slotted quartz tube-flame atomic absorption spectrometry (SQT-FAAS) after dispersive liquid-liquid microextraction (DLLME). The parameters affecting the cadmium complex formation and its extraction output were optimized to obtain high extraction efficiency. These included the pH and amount of the buffer solution, and the concentration of the ligand. The DLLME method was comprehensively optimized based on the type and amount of extraction solvent, dispersive solvent and salt. The type and period of mixing needed for a more effective extraction was also investigated. In order to further improve the sensitivity for the determination of cadmium, the flame atomic absorption spectrometry was fitted with a slotted quartz tube to increase the residence time of cadmium atoms in the pathway of incident light from a hollow cathode lamp. The limits of detection and quantitation (LOD and LOQ) for the FAAS were found to be 42 and 140 μg L- 1, respectively. Under the optimum conditions, LOD and LOQ of the FAAS after DLLME were calculated as 1.3 and 4.4 μg L- 1, respectively. Combining both optimized parameters of the DLLME and SQT-FAAS gave 0.5 and 1.5 μg L- 1 as LOD and LOQ, respectively. Accuracy of the method was also checked using a wastewater certified reference material (EU-L-2), and the result was in good agreement with the certified value.

  3. Absorption spectrum of very low pressure atomic hydrogen

    CERN Document Server

    Moret-Bailly, Jacques

    2015-01-01

    Spectra of quasars result primarily from interactions of natural light with atomic hydrogen. A visible absorption of a sharp and saturated spectral line in a gas requires a low pressure, so a long path without blushing as a cosmological redshift. Burbidge and Karlsson observed that redshifts of quasars result from fundamental redshifts, written 3K and 4K, that cause a shift of absorbed beta and gamma lines of H to alpha gas line. Thus absorbed spectrum is shifted until an absorbed line overlaps with Lyman alpha line of gas: redshift only occurs if an alpha absorption pumps atoms to 2P state. Thus, space is divided into spherical shells centered on the quasar, containing or not 2P atoms. Neglecting collisional de-excitations in absorbing shells, more and more atoms are excited until amplification of a beam having a long path in a shell, thus perpendicular to the observed ray, is large enough for a superradiant flash at alpha frequency. Energy is provided by atoms and observed ray, absorbing a line at local Lym...

  4. Quantitative analysis of immobilized metalloenzymes by atomic absorption spectroscopy.

    Science.gov (United States)

    Opwis, Klaus; Knittel, Dierk; Schollmeyer, Eckhard

    2004-12-01

    A new, sensitive assay for the quantitative determination of immobilized metal containing enzymes has been developed using atomic absorption spectroscopy (AAS). In contrast with conventionally used indirect methods the described quantitative AAS assay for metalloenzymes allows more exact analyses, because the carrier material with the enzyme is investigated directly. As an example, the validity and reliability of the method was examined by fixing the iron-containing enzyme catalase on cotton fabrics using different immobilization techniques. Sample preparation was carried out by dissolving the loaded fabrics in sulfuric acid before oxidising the residues with hydrogen peroxide. The iron concentrations were determined by flame atomic absorption spectrometry after calibration of the spectrometer with solutions of the free enzyme at different concentrations.

  5. Determination of Iron in Layered Crystal Sodium Disilicate and Sodium Silicate by Flame Atomic Absorption Spectrometry with Boric Acid as a Matrix Modifier

    Institute of Scientific and Technical Information of China (English)

    Zhi Hua WANG; Min CAI; Shu Jun WANG

    2006-01-01

    The effects of matrix silicate and experimental conditions on the determination of iron in flame atomic absorption spectrometry (FAAS) were investigated. It was found that boric acid as a matrix modifier obviously eliminated silicate interference. Under the optimum operating conditions, the determination results of iron in layered crystal sodium disilicate and sodium silicate samples by FAAS were satisfactory. The linear range of calibration curve is 0-10.5 μg.mL-1, the relative standard deviation of method is 1.2%-2.2%, the recovery of added iron is 96.0%-101%, the of iron of the standard curve method, standard addition calibration and colorimetry method was the same, but the first has the merits of rapid sample preparation, reduced contamination risks and fast analysis.

  6. [Determination of trace elements in new food sources by flame atomic absorption spectrophotometry].

    Science.gov (United States)

    Liu, Li E; Ding, Li; Qi, Min; Han, Xiu Li; Zhang, Hong-Quan

    2007-07-01

    Samples were digested by HNO3 + HClO4. Flame atomic absorption spectrophotometry (FAAS) was successfully used to determine copper, zinc and iron in new resource food. Under our experimental conditions, the recovery ratio was 94.66%-108.80%; the precision was 0.71%-4.78%. This method of measuring elements is convenient, rapid and accurate. The results showed that there are profitable elements, such as copper, zinc and iron in new resourse food in Henan province. By F test and SNK test, the content sequence of metal elements was found as follows: copper, Chrysanthemum morifolium Ramat = Silkworm pupa > flowers of Pueraria lobata Ohwin = Wheat germ = Codonopsis lanceolata = roots of Pueraria lobata Ohwi > Opuntia dillenii Haw. Zinc, Opuntia dillenii Haw > Silkworm pupa = flowers of Pueraria lobata Ohwi = roots of Pueraria lobata Ohwi = Wheat germ = Codonopsis lanceolata = Chrysanthemum morifolium Ramat. Iron, Silkworm pupa = C hrysanthemum morifolium Ramat = roots of Pueraria lobata Ohwi > flowers of Pueraria lobata Ohwi = Wheat germ = Codonopis lanceolata = Opuntia dillenii Haw.

  7. EVALUATION OF HEAVY METALS CONTENT IN EDIBLE MUSHROOMS BY MICROWAVE DIGESTION AND FLAME ATOMIC ABSORPTION SPECTROMETRY

    Directory of Open Access Journals (Sweden)

    Cristiana Radulescu

    2011-05-01

    Full Text Available The aim of this work was to determine the heavy metal (Cd, Cr, Ni, Pb, Mn, Zn, Fe and Cu content of the fruiting bodies (cap and stipe of four species (Amanita caesarea, Pleurotus ostreatus, Fistulina hepatica and Armillariella mellea and their substrate, collected from forest sites in Dâmboviţa County, Romania. The elements were determined by Flame Atomic Absorption Spectrometry (FAAS after microwave assisted digestion. From the same collecting point were taken n = 5 samples of young and mature fruiting bodies of mushrooms and their substrate. The high concentrations of lead, chrome and cadmium (Pb: 0.25 – 1.89 mg.kg-1, Cr: 0.36 – 1.94 mg.kg-1, Cd: 0.23 – 1.13 mg.kg-1 for all collected wild edible mushrooms, were determined. These data were compared with maximum level for certain contaminants in foodstuffs established by the commission of the European Committees (EC No 466/2001. A quantitative evaluation of the relationship of element uptake by mushrooms from substrate was made by calculating the accumulation coefficient (Ka. The moderately acid pH value of soil influenced the accumulation of Zn and Cd inside of the studied species. The variation of heavy metals content between edible mushrooms species is dependent upon the ability of the species to extract elements from the substrate and on the selective uptake and deposition of metals in tissue.

  8. [Measurement of trace elements in blood serum by atomic absorption spectroscopy with electrothermal atomization].

    Science.gov (United States)

    Rogul'skiĭ, Iu V; Danil'chenko, S N; Lushpa, A P; Sukhodub, L F

    1997-09-01

    Describes a method for measuring trace elements Cr, Mn, Co, Fe, Cu, Zn, and Mo in the blood serum using non-flame atomization (KAC 120.1 complex). Optimal conditions for preparing the samples were defined, temperature regimens for analysis of each element selected, and original software permitting automated assays created. The method permits analysis making use of the minimal samples: 0.1 ml per 10 parallel measurements, which is 100 times less than needed for atomic absorption spectroscopy with flame atomization of liquid samples. Metrological characteristics of the method are assessed.

  9. Extraction and analysis of lead in sweeteners by flow-injection Donnan dialysis with flame atomic absorption spectroscopy.

    Science.gov (United States)

    Antonia, A; Allen, L B

    2001-10-01

    Flow-injection Donnan dialysis is demonstrated for the extraction of lead in sweeteners using flame atomic absorption spectroscopy (FAAS). For spiked concentrations in the low microgram per gram range, recoveries were greater than 90%, and the relative standard deviation was typically less than 10% for a 15-min dialysis procedure. The method detection limit is 350 ng/g. Donnan dialysis is shown to be successful for the extraction of lead in sucrose, corn syrup, and honey but limited in performance for molasses and artificial syrup. This paper also includes a comparison to other procedures for the determination of lead in sweeteners and presents options for realizing improved method performance with Donnan dialysis.

  10. Coprecipitation of trace amounts of silicon with aluminum hydroxide and the determination by flame atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    Ardeshir Shokrollahi

    2014-01-01

    Full Text Available A simple preconcentration method of silicon based on coprecipitation with aluminum hydroxide prior to its flame atomic absorption (FAAS determination was established. The recovery values of analyte ion was higher than 95%. The parameters including types of hydroxide ion source for precipitation, acid type for dissolution step, amount of aluminum ion as collector, pH, temperature, standing and centrifuge time, and sample volume were optimized for the quantitative recovery of the analyte. The influences of matrix ions were also examined. The relative standard deviation was found to be 3.2%. The limit of detection was calculated as (0.1 mg L-1. The preconcentration factor is 100 for (200 mL solution. The proposed method was successfully applied for the determination of silicon in some water and alloy samples.

  11. Solid phase extraction of gold(III) on Amberlite XAD-2000 prior to its flame atomic absorption spectrometric determination.

    Science.gov (United States)

    Elci, Latif; Sahan, Derya; Basaran, Aydan; Soylak, Mustafa

    2007-09-01

    A solid phase extraction method for the determination of gold(III) at trace levels by flame atomic absorption spectrometer (FAAS) was developed. The method was based on retention of gold as chloro complexes through the Amberlite XAD-2000. The effect of some analytical parameters including hydrochloric acid concentration, sample volume, sample and eluent flow rates, eluent volume, eluent concentration and interfering ions on the recovery of gold(III) was investigated. The retention of gold(III) from 1.5 mol l(-1) HCl solution and the recovery of gold with 0.07 mol l(-1) NH3 solution were quantitative (>or=95%). The relative standard deviation (RSD) was calculated as 3.2% (n = 10). The detection limit for gold was 2 microg l(-1). The accuracy was checked with the determination of gold spiked an artificial seawater and a pure copper samples.

  12. FLAME ATOMIC ABSORPTION DETERMINATION OF COPPER IN CEREALS FOOD SAMPLES WITH THE PRECONCENTRATION OF POTASSIUM TETRATITANATE WHISKER

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A simple and reliable method has been developed for separation and preconcentration of trace amounts of copper ions in cereals food for subsequent measurement by flame atomic absorption spectrometry (FAAS). The Cu2+ ions are adsorbed selectively and quantitatively during the passage. The retained copper ions were desorbed from the potassium tetratitanate whisker with 10.0mL of 2mol/L sulphuric acid solutions as eluent and were determined by FAAS. The linear range was 0.05μg/mL~0.20μg/mL in the original solution with a correlation coefficient of 0.9998. The detection limit of the proposed method is 2.1ng/mL in the original solution (3σ, n=9). Determination of copper in standard ions showed that the proposed method has good accuracy (recovery was more than 95%). The method was successfully applied for recovery and determination of copper in cereals food samples.

  13. FLAME ATOMIC ABSORPTION DETERMINATION OF COPPER IN CEREALS FOOD SAMPLES WITH THE PRECONCENTRATION OF POTASSIUM TETRATITANATE WHISKER

    Institute of Scientific and Technical Information of China (English)

    XU Wanzhen; ZHANG Xinghua; YAN Yongsheng; LIU Aiqin; JING Junjie

    2007-01-01

    A simple and reliable method has been developed for separation and preconcentration of trace amounts of copper ions in cereals food for subsequent measurement by flame atomic absorption spectrometry (FAAS). The Cu2+ ions are adsorbed selectively and quantitatively during the passage. The retained copper ions were desorbed from the potassium tetratitanate whisker with 10.0mL of 2mol/L sulphuric acid solutions as eluent and were determined by FAAS. The linear range was 0.05μg/mL~0.20μg/mL in the original solution with a correlation coefficient of 0.9998. The detection limit of the proposed method is 2.1ng/mL in the original solution (3σ, n=9). Determination of copper in standard ions showed that the proposed method has good accuracy (recovery was more than 95%). The method was successfully applied for recovery and determination of copper in cereals food samples.

  14. Cinchocaine hydrochloride determination by atomic absorption spectrometry and spectrophotometry.

    Science.gov (United States)

    Abdel-Ghani, Nour T; Youssef, Ahmed F A; Awady, Mohamed A

    2005-05-01

    Two sensitive spectrophotometric and atomic absorption spectrometric procedures have been developed for determination of cinchocaine hydrochloride (Cin.Cl) in pure form and in pharmaceutical formulation. The spectrophotometric method was based on formation of an insoluble colored ion-associate between the cited drug and tetrathiocyanatocobaltate (CoTC) or hexathiocyanatochromate (CrTC) which dissolved and extracted in an organic solvent. The optimal experimental conditions for quantitative extraction such as pH, concentration of the reagents and solvent were studied. Toluene and iso-butyl alcohol proved to be the most suitable solvents for quantitative extraction of Cin-CoTC and Cin-CrTC ion-associates with maximum absorbance at 620 and 555 nm, respectively. The optimum concentration ranges, molar absorptivities, Ringbom ranges and Sandell sensitivities were also evaluated. The atomic absorption spectrometric method is based on measuring of the excess cobalt or chromium in the aqueous solution, after precipitation of the drug, at 240.7 and 357.9 nm, respectively. Linear application ranges, characteristic masses and detection limits were 57.99-361.9, 50.40 and 4.22 microg ml(-1) of Cin.Cl, in case of CoTC, while 37.99-379.9, 18.94 and 0.81 microg ml(-1) in case of CrTC.

  15. A Comprehensive X-Ray Absorption Model for Atomic Oxygen

    Science.gov (United States)

    Gorczyca, T. W.; Bautista, M. A.; Hasoglu, M. F.; Garcia, J.; Gatuzz, E.; Kaastra, J. S.; Kallman, T. R.; Manson, S. T.; Mendoza, C.; Raassen, A. J. J.; de Vries, C. P.; Zatsarinny, O.

    2013-01-01

    An analytical formula is developed to accurately represent the photoabsorption cross section of atomic Oxygen for all energies of interest in X-ray spectral modeling. In the vicinity of the K edge, a Rydberg series expression is used to fit R-matrix results, including important orbital relaxation effects, that accurately predict the absorption oscillator strengths below threshold and merge consistently and continuously to the above-threshold cross section. Further, minor adjustments are made to the threshold energies in order to reliably align the atomic Rydberg resonances after consideration of both experimental and observed line positions. At energies far below or above the K-edge region, the formulation is based on both outer- and inner-shell direct photoionization, including significant shake-up and shake-off processes that result in photoionization-excitation and double-photoionization contributions to the total cross section. The ultimate purpose for developing a definitive model for oxygen absorption is to resolve standing discrepancies between the astronomically observed and laboratory-measured line positions, and between the inferred atomic and molecular oxygen abundances in the interstellar medium from XSTAR and SPEX spectral models.

  16. The determination of vanadium in brines by atomic absorption spectroscopy

    Science.gov (United States)

    Crump-Wiesner, Hans J.; Feltz, H.R.; Purdy, W.C.

    1971-01-01

    A standard addition method is described for the determination of vanadium in brines by atomic absorption spectroscopy with a nitrous oxide-acetylene flame. Sample pH is adjusted to 1.0 with concentrated hydrochloric acid and the vanadium is directly extracted with 5% cupferron in methyl isobutyl ketone (MIBK). The ketone layer is then aspirated into the flame and the recorded absorption values are plotted as a function of the concentration of the added metal. As little as 2.5 ??g l-1 of vanadium can be detected under the conditions of the procedure. Tungsten and tin interfere when present in excess of 5 and 10 ??g ml-1, respectively. The concentrations of the two interfering ions normally found in brines are well below interference levels. ?? 1971.

  17. Spectrofluorimetric, Atomic Absorption Spectrometric and Spectrophotometric Determination of Some Fluoroquinolones

    Directory of Open Access Journals (Sweden)

    Hesham Salem

    2005-01-01

    Full Text Available Simple, accurate, sensitive and selective spectrofluorimetric, atomic absorption spectrometric and spectrophotometric methods are described for the quantitative determination of ten fluoroquinolones (amifloxacin, ciprofloxacin hydrochloride, difloxacin hydrochloride, enoxacin, enrofloxacin, lomefloxacin hydrochloride, levofloxacin, norfloxacin, ofloxacin and pefloxacin mesylate. The first method was a spectrofluorimetric method in which samples of the studied drugs in 0.1 N H2SO4 showed native fluorescence at 450 nm when excitation was at 290 nm. The calibration graph was rectilinear from 0.3-1.4 μg mL-1 (method I. Cobalt sulphate was used for precipitation of the ion associates formed from the reaction with the cited drugs. The formation and solubility of the solid complexes at the optimum conditions of pH and ionic strength values have been studied. The method depends on direct determination of the ions in the precipitate or indirect determination of the ions in the filtrate by atomic absorption spectroscopy. The optimum conditions for precipitation were carefully studied. Rectilinear calibration graphs were obtained in the range of 3-30 μg mL-1 for each of the investigated drugs. The molar ratios of the formed chelats were determined by Job's method and their association constants were also calculated (method II. Ammonium vanadate was used for the spectrophotometric determination of the selected fluoroquinolones by oxidation in sulphuric acid medium resulting in the development of a greenish blue colour measured at 766 nm which was attributed to the vanadium (IV produced by reduction of vanadium (V by the selected drugs. The optimum conditions for heating time, reagent concentration and sulphuric acid concentration were carefully studied. The accuracy and precision of the proposed method was confirmed by estimating five or six replicates within Beer's law limits were obtained in the range 10-40 μg mL-1 for each of the investigated drugs

  18. Ultratrace determination of tin by hydride generation in-atomizer trapping atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Průša, Libor [Institute of Analytical Chemistry of the ASCR, v. v. i., Veveří 97, 602 00 Brno (Czech Republic); Charles University in Prague, Faculty of Science, Department of Analytical Chemistry, Hlavova 8, Prague 2, CZ 128 43 Czech Republic (Czech Republic); Dědina, Jiří [Institute of Analytical Chemistry of the ASCR, v. v. i., Veveří 97, 602 00 Brno (Czech Republic); Kratzer, Jan, E-mail: jkratzer@biomed.cas.cz [Institute of Analytical Chemistry of the ASCR, v. v. i., Veveří 97, 602 00 Brno (Czech Republic)

    2013-12-04

    Graphical abstract: -- Highlights: •In-atomizer trapping HG-AAS was optimized for Sn. •A compact quartz trap-and-atomizer device was employed. •Generation, preconcentration and atomization steps were investigated in detail. •Hundred percent preconcentration efficiency for tin was reached. •Routine analytical method was developed for Sn determination (LOD of 0.03 ng mL{sup −1} Sn). -- Abstract: A quartz multiatomizer with its inlet arm modified to serve as a trap (trap-and-atomizer device) was employed to trap tin hydride and subsequently to volatilize collected analyte species with atomic absorption spectrometric detection. Generation, atomization and preconcentration conditions were optimized and analytical figures of merit of both on-line atomization as well as preconcentration modes were quantified. Preconcentration efficiency of 95 ± 5% was found. The detection limits reached were 0.029 and 0.14 ng mL{sup −1} Sn, respectively, for 120 s preconcentration period and on-line atomization mode without any preconcentration. The interference extent of other hydride forming elements (As, Se, Sb and Bi) on tin determination was found negligible in both modes of operation. The applicability of the developed preconcentration method was verified by Sn determination in a certified reference material as well as by analysis of real samples.

  19. ADSORPTION BEHAVIOUR OF Mn(Ⅱ) AND Zn(Ⅱ) ON ATTAPULGITE WITH FAAS METHOD

    Institute of Scientific and Technical Information of China (English)

    LI Bingbing; LI Chunxiang; LIU Aiqin; XIAO Bo

    2008-01-01

    Active attapulbgite as adsorptive reagent, the adsorptive behavior of Mn(Ⅱ) and Zn(Ⅱ) was studied with Flame atomic absorption spectroscopy (FAAS) method.The mainly factors of influencing the adsorption and desorption of Mn(Ⅱ) and Zn(Ⅱ) were discussed.The interference of coexisting ions was investigated, and the actual sample determination from adzuki beans, mung beans and phosphating waste water was conducted with good result.

  20. ADSORPTION BEHAVIOUR OF Mn(Ⅱ) AND Zn(Ⅱ) ON ATTAPULGITE WITH FAAS METHOD

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Active attapulbgite as adsorptive reagent, the adsorptive behavior of Mn(II) and Zn(II) was studied with Flame atomic absorption spectroscopy (FAAS) method. The mainly factors of influencing the adsorption and desorption of Mn(II) and Zn(II) were discussed. The interference of coexisting ions was investigated, and the actual sample determination from adzuki beans, mung beans and phosphating waste water was conducted with good result.

  1. SPECTROPHOTOMETRIC, ATOMIC ABSORPTION AND CONDUCTOMETRIC ANALYSIS OF TRAMADOL HYDROCHLORIDE

    Directory of Open Access Journals (Sweden)

    Sara M. Anis

    2011-09-01

    Full Text Available Six simple and sensitive spectroscopic and conductometric procedures (A-F were developed for the determination of tramadol hydrochloride. Methods A, B and C are based on the reaction of cobalt (II thiocyanate with tramadol to form a stable ternary complex, which could be measured by spectrophotometric (method A, atomic absorption (method B or conductometric (method C procedures. Methods D and E depend on the reaction of molybdenum thiocyanate with tramadol to form a stable ternary complex, measured by spectrophotometric means (method D or by atomic absorption procedures (method E, while method F depends on the formation of an ion pair complex between the studied drug and bromothymol blue which is extractable into methylene chloride. Tramadol hydrochloride could be assayed in the range of 80-560 and 40-–220 μg ml-1, 1-15 mg ml-1 and 2.5-22.5, 1.25-11.25 and 5-22 μg ml-1 using methods A,B,C,D,E and F, respectively. Various experimental conditions were studied. The results obtained showed good recoveries. The proposed procedures were applied successfully to the analysis of tramadol in its pharmaceutical preparations and the results were favorably comparable with the official method.

  2. Transient absorption spectra of the laser-dressed hydrogen atom

    Science.gov (United States)

    Murakami, Mitsuko; Chu, Shih-I.

    2013-10-01

    We present a theoretical study of transient absorption spectra of laser-dressed hydrogen atoms, based on numerical solutions of the time-dependent Schrödinger equation. The timing of absorption is controlled by the delay between an extreme ultra violet (XUV) pulse and an infrared (IR) laser field. The XUV pulse is isolated and several hundred attoseconds in duration, which acts as a pump to drive the ground-state electron to excited p states. The subsequent interaction with the IR field produces dressed states, which manifest as sidebands between the 1s-np absorption spectra separated by one IR-photon energy. We demonstrate that the population of dressed states is maximized when the timing of the XUV pulse coincides with the zero crossing of the IR field, and that their energies can be manipulated in a subcycle time scale by adding a chirp to the IR field. An alternative perspective to the problem is to think of the XUV pulse as a probe to detect the dynamical ac Stark shifts. Our results indicate that the accidental degeneracy of the hydrogen excited states is removed while they are dressed by the IR field, leading to large ac Stark shifts. Furthermore, we observe the Autler-Townes doublets for the n=2 and 3 levels using the 656 nm dressing field, but their separation does not agree with the prediction by the conventional three-level model that neglects the dynamical ac Stark shifts.

  3. Antimony quantification in Leishmania by electrothermal atomic absorption spectroscopy.

    Science.gov (United States)

    Roberts, W L; Rainey, P M

    1993-05-15

    Tri- and pentavalent antimony were quantified in Leishmania mexicana pifanoi amastigotes and promastigotes by atomic absorption spectroscopy with electrothermal atomization. Leishmania grown in axenic culture were treated with either potassium antimony tartrate [Sb(III)] or sodium stibogluconate [Sb(V)]. The parasites were collected, digested with nitric acid, and subjected to atomic absorption spectroscopy. The method was linear from 0 to 7 ng of antimony. The interassay coefficients of variation were 9.6 and 5.7% (N = 5) for 0.52 and 3.7-ng samples of leishmanial antimony, respectively. The limit of detection was 95 pg of antimony. The assay was used to characterize Sb(III) and Sb(V) influx and efflux kinetics. Influx rates were determined at antimony concentrations that produced a 50% inhibition of growth (IC50). The influx rates of Sb(V) into amastigotes and promastigotes were 4.8 and 12 pg/million cells/h, respectively, at 200 micrograms antimony/ml. The influx rate of Sb(III) into amastigotes was 41 pg/million cells/h at 20 micrograms antimony/ml. Influx of Sb(III) into promastigotes at 1 microgram antimony/ml was rapid and reached a plateau of 175 pg/million cells in 2 h. Efflux of Sb(III) and Sb(V) from amastigotes and promastigotes exhibited biphasic kinetics. The initial (alpha) half-life of Sb(V) efflux was less than 4 min and that of Sb(III) was 1-2 h. The apparent terminal (beta) half-lives ranged from 7 to 14 h.

  4. Determination of metals in lubricating oils by flame atomic absorption spectrometry using a single-bore high-pressure pneumatic nebulizer.

    Science.gov (United States)

    Mora, J; Todolí, J L; Sempere, F J; Canals, A; Hernandis, V

    2000-12-01

    The behaviour of a single-bore high-pressure pneumatic nebulizer (SBHPPN) as a tool for the analysis of lubricating oils by flame atomic absorption spectrometry (FAAS) was investigated. The effects of the sample oil content [from 10% to 100% (w/w) oil in 4-methylpentan-2-one, IBMK] and the carrier nature (IBMK and methanol) on the characteristics of the aerosols generated, on the analyte transport efficiency and on the analytical figures of merit in FAAS were studied. A pneumatic concentric nebulizer (PCN) was used for comparison. Increasing the oil content increases the viscosity of the sample. With the PCN this gives rise to coarser aerosols, making it impossible to nebulize samples with an oil content higher than 70% (w/w). Using the SBHPPN, the viscosity of the sample scarcely affects the characteristics of the primary aerosols. Hence, the SBHPPN is able, by using the appropriate carrier, to nebulize pure lubricating oils. Among the carriers tested, IBMK is the most advisable because it is fully miscible with all the oil samples. The SBHPPN provides higher sensitivities and lower limits of detection than the PCN. Compared with a method based on organic dilution, the use of the SBHPPN for the direct analysis of lubricating oils by FAAS makes it possible, in addition to increasing the analysis throughput, to detect elements at lower concentrations. Moreover, the SBHPPN provides similar results to those obtained using a previous acid digestion step.

  5. Sistema automático para análise direta de ligas metálicas por eletrodissolução anódica e espectrometria de absorção atômica On-line anodic electrodissolution system for direct determination of metallic alloys by atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    José Bento B. Silva

    1999-02-01

    Full Text Available An automatic system for the direct determination of lead and tin by atomic absorption spectrometry is described. The on-line treatment of the metallic samples was obtained by anodic electrodissolution in a flow injection system. Lead was determined by flame atomic absorption spectrometry (FAAS and tin by graphite furnace atomic absorption spectrometry (GFAAS. A computer program managed the current source and the solenoid valves that direct the fluids. Good linear correlations between absorbance and current intensity for lead and tin were observed. Results were in agreement with the certified values. Precision was always better than 5%. The recommended procedure allows the direct determination of 60 or 30 elements/h using FAAS or GFAAS, respectively.

  6. Observations of Absorption Lines from Highly Ionized Atoms

    Science.gov (United States)

    Jenkins, E. B.

    1984-01-01

    In the ultraviolet spectra of hot stars, absorption lines can be seen from highly ionized species in the interstellar medium. Observations of these features which have been very influential in revising the perception of the medium's various physical states, are discussed. The pervasiveness of O 6 absorption lines, coupled with complementary observations of a diffuse background in soft X-rays and EUV radiation, shows that there is an extensive network of low density gas (n approx. fewX 0.001/cucm) existing at coronal temperatures, 5.3 or = log T or = 6.3. Shocks created by supernova explosions or mass loss from early-type stars can propagate freely through space and eventually transfer a large amount of energy to the medium. To create the coronal temperatures, the shocks must have velocities in excess of 150 km/sec; shocks at somewhat lower velocity 9v or = 100 km/sec) can be directly observed in the lines of Si3. Observations of other lines in the ultraviolet, such as Si 4V and C 5, may highlight the widespread presence of energetic uv radiation from very hot, dward stars. More advanced techniques in visible and X-ray astronomical spectroscopy may open up for inspection selected lines from atoms in much higher stages of ionization.

  7. Preconcentration and determination of trace silver ion using benzothiazole calix[4]arene modified silica by flow injection flame atomic absorption spectrometry.

    Science.gov (United States)

    Waluvanaruk, Jitwilai; Aeungmaitrepirom, Wanlapa; Tuntulani, Thawatchai; Ngamukot, Passapol

    2014-01-01

    The silica gel modified with benzothiazole calix[4]arene (APS-L1) via Schiff's base reaction was applied as a sorbent in an online system for preconcentration and determination of silver ion by flame atomic absorption spectrometry (FAAS). APS-L1 was used as an effective sorbent for solid phase extraction (SPE) of silver(I) ion in both batch and column methods. The optimum experimental parameters such as pH, eluent type, sample flow rate, eluent volume and eluent flow rate including the effect of interfering ions were investigated. Silver(I) ion was determined at pH 6-7. The capacity of APS-L1 sorbent was found to be 12.2 mg/g of sorbent. The high affinity was obtained without interference from the interfering ions. The optimum conditions of the online flow injection preconcentration coupled with the FAAS (FI-FAAS system) were evaluated. The sample flow rate was 3.0 mL min(-1) using sample volume of 5-10 mL. Elution was performed with 250 μL of 0.1 mol L(-1) thiosulfate at the flow rate of 1.5 mL min(-1). The analytical characteristics and performance of the FI-FAAS system were studied under optimum conditions using a solution spiked with standard silver(I) ion at 20 and 50 μg L(-1). The detection limit of 0.44 μg L(-1) was obtained. The accuracy of the proposed method was evaluated and percentages of recovery at 20 and 50 μg L(-1) were 100.2 and 99.5%, respectively. The percent relative standard deviations (%RSD) at 20 and 50 μg L(-1) were 6.1 and 3.3%, respectively. The developed method was successfully applied to determine trace silver(I) ion in drinking and tap water samples.

  8. Etalon-induced baseline drift and correction in atom flux sensors based on atomic absorption spectroscopy

    Science.gov (United States)

    Du, Yingge; Chambers, Scott A.

    2014-10-01

    Atom flux sensors based on atomic absorption (AA) spectroscopy are of significant interest in thin film growth as they can provide unobtrusive, element specific real-time flux sensing and control. The ultimate sensitivity and performance of these sensors are strongly affected by baseline drift. Here we demonstrate that an etalon effect resulting from temperature changes in optical viewport housings is a major source of signal instability, which has not been previously considered, and cannot be corrected using existing methods. We show that small temperature variations in the fused silica viewports can introduce intensity modulations of up to 1.5% which in turn significantly deteriorate AA sensor performance. This undesirable effect can be at least partially eliminated by reducing the size of the beam and tilting the incident light beam off the viewport normal.

  9. Etalon-induced Baseline Drift And Correction In Atom Flux Sensors Based On Atomic Absorption Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Du, Yingge; Chambers, Scott A.

    2014-10-20

    Atom flux sensors based on atomic absorption (AA) spectroscopy are of significant interest in thin film growth as they can provide unobtrusive, element specific, real-time flux sensing and control. The ultimate sensitivity and performance of the sensors are strongly affected by the long-term and short term baseline drift. Here we demonstrate that an etalon effect resulting from temperature changes in optical viewport housings is a major source of signal instability which has not been previously considered or corrected by existing methods. We show that small temperature variations in the fused silica viewports can introduce intensity modulations of up to 1.5%, which in turn significantly deteriorate AA sensor performance. This undesirable effect can be at least partially eliminated by reducing the size of the beam and tilting the incident light beam off the viewport normal.

  10. Etalon-induced baseline drift and correction in atom flux sensors based on atomic absorption spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Du, Yingge, E-mail: yingge.du@pnnl.gov [Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99352 (United States); Chambers, Scott A. [Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352 (United States)

    2014-10-20

    Atom flux sensors based on atomic absorption (AA) spectroscopy are of significant interest in thin film growth as they can provide unobtrusive, element specific real-time flux sensing and control. The ultimate sensitivity and performance of these sensors are strongly affected by baseline drift. Here we demonstrate that an etalon effect resulting from temperature changes in optical viewport housings is a major source of signal instability, which has not been previously considered, and cannot be corrected using existing methods. We show that small temperature variations in the fused silica viewports can introduce intensity modulations of up to 1.5% which in turn significantly deteriorate AA sensor performance. This undesirable effect can be at least partially eliminated by reducing the size of the beam and tilting the incident light beam off the viewport normal.

  11. Simultaneous flow injection preconcentration of lead and cadmium using cloud point extraction and determination by atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Edson Luiz [Centro de Energia Nuclear na Agricultura, Universidade de Sao Paulo, Av. Centenario, 303, CP 96, 13416-000 Piracicaba, SP (Brazil)], E-mail: edsonqmc@hotmail.com; Santos Roldan, Paulo dos [Centro de Energia Nuclear na Agricultura, Universidade de Sao Paulo, Av. Centenario, 303, CP 96, 13416-000 Piracicaba, SP (Brazil)

    2009-01-15

    A flow injection (FI) micelle-mediated separation/preconcentration procedure for the determination of lead and cadmium by flame atomic absorption spectrometry (FAAS) has been proposed. The analytes reacted with 1-(2-thiazolylazo)-2-naphthol (TAN) to form hydrophobic chelates, which were extracted into the micelles of 0.05% (w/v) Triton X-114 in a solution buffered at pH 8.4. In the preconcentration stage, the micellar solution was continuously injected into a flow system with four mini-columns packed with cotton, glass wool, or TNT compresses for phase separation. The analytes-containing micelles were eluted from the mini-columns by a stream of 3 mol L{sup -1} HCl solution and the analytes were determined by FAAS. Chemical and flow variables affecting the preconcentration of the analytes were studied. For 15 mL of preconcentrated solution, the enhancement factors varied between 15.1 and 20.3, the limits of detection were approximately 4.5 and 0.75 {mu}g L{sup -1} for lead and cadmium, respectively. For a solution containing 100 and 10 {mu}g L{sup -1} of lead and cadmium, respectively, the R.S.D. values varied from 1.6 to 3.2% (n = 7). The accuracy of the preconcentration system was evaluated by recovery measurements on spiked water samples. The method was susceptible to matrix effects, but these interferences were minimized by adding barium ions as masking agent in the sample solutions, and recoveries from spiked sample varied in the range of 95.1-107.3%.

  12. Determination of Aluminum Concentration in Seawater by Colorimetry and Atomic Absorption Spectroscopy.

    Science.gov (United States)

    1972-11-30

    this was also high. 5 . ,Irj ~ - • lri*; llo. TALLE 2 ATOMIC ABSORPTION SPECTROSCOPY DETEPIJINATION OF ALUMINU1 CONCENTRATIO11 OF SEAWATER OCEAN...Concentration in Seawater by Colorimetr-y and Atomic Absorption Spectroscopy Charles A. Greene, Jr. and Everett N. Jones Ocean Science Department T14

  13. Atomic Absorption Spectrophotometric Determination of Lead in White Rice

    Directory of Open Access Journals (Sweden)

    Sherryl M. Montalbo

    2015-11-01

    Full Text Available Recent studies on the heavy metal content of rice from various parts of the world have alarmed rice-eating nations, including the Philippines. In 2013, Philippine Rice Research Institute (PhilRice reported that rice in the Philippines needs to be evaluated to determine whether these contain heavy metals such as lead. This research aimed to assess the presence of lead in the three highest selling rice varieties harvested in Oriental Mindoro and sold in Batangas City public markets. It was done to asses if the lead concentration in the raw and cooked rice samples conform to the maximum acceptable level in food established by Joint FAO/WHO Expert Committee on Food Additives (JECFA Program Codex Alimentarius Commission. Survey analysis showed that the three highest selling rice varieties during the period when this study was conducted were Sinandomeng, Dinorado and C-4 Dinorado respectively. Lead analysis of rice samples was carried out using Flame Atomic Absorption Spectroscopy. The lead content in both the raw and cooked rice samples were not detected, meaning that the lead concentration were either not present or may be present but is less than the detection limit of the instrument used. The lead concentration in the rice samples from Oriental Mindoro conformed to the standards for food safety for lead content in rice, which is 0.2 mg/kg or 0.2 ppm, set by the Codex Alimentarius Commission.

  14. Determination of gold in geologic materials by solvent extraction and atomic-absorption spectrometry

    Science.gov (United States)

    Huffman, Claude; Mensik, J.D.; Riley, L.B.

    1967-01-01

    The two methods presented for the determination of traces of gold in geologic materials are the cyanide atomic-absorption method and the fire-assay atomic-absorption method. In the cyanide method gold is leached with a sodium-cyanide solution. The monovalent gold is then oxidized to the trivalent state and concentrated by extracting into methyl isobutyl ketone prior to estimation by atomic absorption. In the fire-assay atomic-absorption method, the gold-silver bead obtained from fire assay is dissolved in nitric and hydrochloric acids. Gold is then concentrated by extracting into methyl isobutyl ketone prior to determination by atomic absorption. By either method concentrations as low as 50 parts per billion of gold can be determined in a 15-gram sample.

  15. Feasibility of filter atomization in high-resolution continuum source atomic absorption spectrometry

    Science.gov (United States)

    Heitmann, Uwe; Becker-Ross, Helmut; Katskov, Dmitri

    2006-03-01

    A prototype spectrometer for high-resolution continuum source atomic absorption spectrometry (HR-CS AAS), built at ISAS Berlin, Germany, was combined with a graphite filter atomizer (GFA), earlier developed at TUT, Pretoria, South Africa. The furnace and auto-sampler units from a commercial AA spectrometer, model AAS vario 6 (Analytik Jena AG, Jena, Germany), were employed in the instrument. Instead of conventional platform tube, the GFA was used to provide low measurement susceptibility to interferences and short determination cycle. The GFA was modified according to the design of the furnace unit and optimal physical parameters of its components (filter and collector) found. Afterwards, optimal GFA was replicated and tested to outline analytical performances of the HR-CS GFA AA spectrometer in view of prospects of multi-element analysis. In particular, reproducibility of performances, repeatability of analytical signals, lifetime, temperature limit and duration of the measurement cycle were examined, and elements available for determination justified. The results show that the peak area of the atomic absorption signal is reproduced in various GFA copies within ± 4% deviation range. The GFA can stand temperatures of 2800 °C with 6 s hold time for 55 temperature cycles, and 2700 °C (8 s) for about 200 cycles. Only the external tube is prone to destruction while the filter and collector do not show any sign of erosion caused by temperature or aggressive matrix. Analytical signals are affected insignificantly by tube aging. Repeatability of the peak area remains within 1.1-1.7% RSD over more than hundred determination cycles. Peak areas are proportional to the sample volume of injected organic and inorganic liquids up to at least 50 μL. The drying stage is combined with hot sampling and cut down to 15-20 s. The list of metals available for determination with full vapor release includes Al, Co, Cr, Ni, Pt as well as more volatile metals. Characteristic masses at

  16. Dithiocarbamate functionalized or surface sorbed Merrifield resin beads as column materials for on line flow injection-flame atomic absorption spectrometry determination of lead.

    Science.gov (United States)

    Praveen, R S; Naidu, G R K; Prasada Rao, T

    2007-09-26

    This article describes the preparation of dithiocarbamate immobilized/functionalized and diethylammonium dithiocarbamate (DDTC) sorbed Merrifield Chloromethylated Resin (MCR) beads and comparison of these materials for on-line flow injection (FI)-flame atomic absorption spectrometry (FAAS) determination of lead. The above two materials enrich lead quantitatively over an identical optimal pH range (8.0-9.0), a preconcentration/loading time (up to 4 min) and elution with acidified methanol (a minimum of 0.01 molL(-1) HNO(3) in methanol). However, the detection limit for lead using dithiocarbamate functionalized MCR beads is 1.3 microgL(-1) compared to 3 microgL(-1) for DDTC sorbed MCR beads. Again, the sensitivity enhancement over direct FAAS signal is 48- and 27-fold, respectively. In addition, dithiocarbamate functionalized MCR beads offers better precision compared to DDTC sorbed MCR beads as the corresponding relative standard deviation (R.S.D.) values for five successive determinations of 0.20 microgmL(-1) are 1.44 and 4.36%, respectively. The accuracy of the developed on-line FI-FAAS procedure employing dithiocarbamate functionalized MCR beads as column material was tested by analyzing Certified Reference Material (CRM) of soil (IAEA soil-7) and marine sediment reference material (MESS-3) supplied by International Atomic Energy Agency (IAEA), Vienna and National Research Council (NRC), Canada, respectively. Furthermore, the developed procedure has been successfully tested for the analysis of surface, pond, ground and effluent water and soil samples collected from the vicinity of lead acid battery industry in India.

  17. Separation of seven arsenic compounds by high-performance liquid chromatography with on-line detection by hydrogen–argon flame atomic absorption spectrometry and inductively coupled plasma mass spectrometry

    DEFF Research Database (Denmark)

    Hansen, S. H.; Larsen, E. H.; Pritzl, G.

    1992-01-01

    Seven molecular forms of arsenic were separated by anion- and cation-exchange high-performance liquid chromatography (HPLC) with on-line detection by flame atomic absorption spectrometry (FAAS). The interfacing was established by a vented poly(tetrafluoroethylene) capillary tubing connecting...... the HPLC column to the nebulizer of the atomic absorption spectrometer. Arsenite, arsenate, monomethylarsonate (MMA) and dimethylarsinate (DMA) were separated from each other and from the co-injected cationic arsenic compounds, arsenobetaine (AsB), arsenocholine (AsC) and the tetramethylarsonium ion (TMAs......-to-noise ratio of the on-line AAS detector was optimized. This involved the use of the hydrogen-argon-entrained air flame, a slotted tube atom trap in the flame for signal enhancement, electronic noise damping and a high-intensity light source. The detection limits in mu-g cm-3, using 100 mm3 injections...

  18. Separation of seven arsenic compounds by high performance liquid chromatography with on-line detection by hydrogen-argon flame atomic absorption spectrometry and inductively coupled plasma mass spectrometry

    DEFF Research Database (Denmark)

    Hansen, S. H.; Larsen, Erik Huusfeldt; Pritzl, G.

    1992-01-01

    Seven molecular forms of arsenic were separated by anion- and cation-exchange high-performance liquid chromatography (HPLC) with on-line detection by flame atomic absorption spectrometry (FAAS). The interfacing was established by a vented poly(tetrafluoroethylene) capillary tubing connecting...... the HPLC column to the nebulizer of the atomic absorption spectrometer. Arsenite, arsenate, monomethylarsonate (MMA) and dimethylarsinate (DMA) were separated from each other and from the co-injected cationic arsenic compounds, arsenobetaine (AsB), arsenocholine (AsC) and the tetramethylarsonium ion (TMAs......-to-noise ratio of the on-line AAS detector was optimized. This involved the use of the hydrogen-argon-entrained air flame, a slotted tube atom trap in the flame for signal enhancement, electronic noise damping and a high-intensity light source. The detection limits in mu-g cm-3, using 100 mm3 injections...

  19. Cloud point extraction for the preconcentration of silver and palladium in real samples and determination by atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Tavallali, Hossein; Yazdandoust, Saeed; Yazdandoust, Mozhdeh [Department of Chemistry, Payame Noor University (PNU), Shiraz (Iran)

    2010-03-15

    A cloud point extraction procedure is presented for the preconcentration and simultaneous determination of Ag{sup +} and Pd{sup 2+} in various samples. After complexation with 2-((2-((1H-benzo[d]imidazole-2-yl)methoxy)phenoxy)methyl)-1H-benzo[d]imidazol (BIMPI), which was used as a new chelating agent, analyte ions were quantitatively extracted to a phase rich in Triton X-114 following centrifugation, and determination was carried out by flame atomic absorption spectrometry (FAAS). Under the optimum experimental conditions (i. e., pH = 7.0, 15.0.10{sup -5} mol/L BIMPI and 0.036% (w/v) Triton X-114), calibration graphs were linear in the range of 28.0-430.0 {mu}g/L and 57.0-720.0 {mu}g/L with detection limits of 10.0 and 25.0 {mu}g/L for Ag{sup +} and Pd{sup 2+}, respectively. The enrichment factors were 35.0 and 28.0 for Ag{sup +} and Pd{sup 2+}, respectively. The method has been successfully applied to evaluate these metals in some real samples, including waste water, soil and hydrogenation catalyst samples. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  20. Preconcentration procedure using cloud point extraction in the presence of electrolyte for cadmium determination by flame atomic absorption spectrometry

    Science.gov (United States)

    Coelho, Luciana Melo; Arruda, Marco Aurélio Zezzi

    2005-06-01

    This paper describes a micelle-mediated phase separation in the presence of electrolyte as a preconcentration method for cadmium determination by flame atomic absorption spectrometry (FAAS). Cadmium was complexed with ammonium O,O-diethyldithiophosphate (DDTP) in an acidic medium (0.32 mol l- 1 HCl) using Triton X-114 as surfactant and quantitatively extracted into a small volume (about 20 μl) of the surfactant-rich phase after centrifugation. The chemical variables that affect the cloud point extraction, such as complexing time (0 20 min), Triton X114 concentration (0.043 0.87% w/v) and complexing agent concentration (0.01 0.1 mol l- 1), were investigated. The cloud point is formed in the presence of NaCl at room temperature (25 °C), and the electrolyte concentration (0.5 5% w/v) was also investigated. Under optimized conditions, only 8 ml of sample was used in the presence of 0.043% w/v Triton X-114 and 1% (w/v) NaCl. This method permitted limits of detection and quantification of 0.9 μg l- 1 and 2.9 μg l- 1 Cd, respectively, and a linear calibration range from 3 to 400 μg l- 1 Cd. The proposed method was applied to Cd determination in physiological solutions (containing 0.9% (w/v) of NaCl), mineral water, lake water and cigarette samples (tobacco).

  1. Cloud point extraction for the determination of copper, nickel and cobalt ions in environmental samples by flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Ghaedi, M. [Chemistry Department, University of Yasouj, Yasouj 75914-353 (Iran, Islamic Republic of)], E-mail: m_ghaedi@mail.yu.ac.ir; Shokrollahi, A.; Ahmadi, F.; Rajabi, H.R. [Chemistry Department, University of Yasouj, Yasouj 75914-353 (Iran, Islamic Republic of); Soylak, M. [Chemistry Department, University of Erciyes, 38039 Kayseri (Turkey)

    2008-02-11

    A cloud point extraction procedure was presented for the preconcentration of copper, nickel and cobalt ions in various samples. After complexation with methyl-2-pyridylketone oxime (MPKO) in basic medium, analyte ions are quantitatively extracted to the phase rich in Triton X-114 following centrifugation. 1.0 mol L{sup -1} HNO{sub 3} nitric acid in methanol was added to the surfactant-rich phase prior to its analysis by flame atomic absorption spectrometry (FAAS). The adopted concentrations for MPKO, Triton X-114 and HNO{sub 3}, bath temperature, centrifuge rate and time were optimized. Detection limits (3 SDb/m) of 1.6, 2.1 and 1.9 ng mL{sup -1} for Cu{sup 2+}, Co{sup 2+} and Ni{sup 2+} along with preconcentration factors of 30 and for these ions and enrichment factor of 65, 58 and 67 for Cu{sup 2+}, Ni{sup 2+} and Co{sup 2+}, respectively. The high efficiency of cloud point extraction to carry out the determination of analytes in complex matrices was demonstrated. The proposed procedure was applied to the analysis of biological, natural and wastewater, soil and blood samples.

  2. Cloud point extraction and flame atomic absorption spectrometry combination for copper(II) ion in environmental and biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Shokrollahi, Ardeshir [Chemistry Department, Yasouj University, Yasouj 75914-353 (Iran, Islamic Republic of)], E-mail: ashokrollahi@mail.yu.ac.ir; Ghaedi, Mehrorang [Chemistry Department, Yasouj University, Yasouj 75914-353 (Iran, Islamic Republic of)], E-mail: m_ghaedi@mail.yu.ac.ir; Hossaini, Omid; Khanjari, Narges [Chemistry Department, Yasouj University, Yasouj 75914-353 (Iran, Islamic Republic of); Soylak, Mustafa [Chemistry Department, University of Erciyes, 38039 Kayseri (Turkey)

    2008-12-30

    A cloud point extraction procedure was presented for the preconcentration of copper(II) ion in various samples. After complexation by 4-(phenyl diazenyl) benzene-1,3-diamine (PDBDM) (chrysoidine), copper(II) ions were quantitatively recovered in Triton X-114 after centrifugation. 0.5 ml of methanol acidified with 1.0 mol L{sup -1} HNO{sub 3} was added to the surfactant-rich phase prior to its analysis by flame atomic absorption spectrometry (FAAS). The influence of analytical parameters including ligand, Triton X-114 and HNO{sub 3} concentrations, bath temperature, heating time, centrifuge rate and time were optimized. The effect of the matrix ions on the recovery of copper(II) ions was investigated. The detection limit (3S.D.{sub b}/m, n = 10) of 0.6 ng mL{sup -1} along with preconcentration factor of 30 and enrichment factor of 41.1 with R.S.D. of 1.0% for Cu was achieved. The proposed procedure was applied to the analysis of various environmental and biological samples.

  3. Preconcentration and determination of zinc and lead ions by a combination of cloud point extraction and flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Tavallali, H. [Chemistry Department, Payamenore University, Shiraz (Iran); Shokrollahi, A.; Zahedi, M. [Chemistry Department, Yasouj University, Yasouj (Iran); Niknam, K. [Chemistry Department, Persian Gulf University, Bushehr (Iran); Soylak, M. [Chemistry Department, University of Erciyes, Kayseri (Turkey); Ghaedi, M.

    2009-04-15

    The phase-separation phenomenon of non-ionic surfactants occurring in aqueous solution was used for the extraction of lead(II) and zinc(II). After complexation with 3-[(4-bromophenyl) (1-H-inden-3-yl)methyl]-1 H-indene (BPIMI), the analytes were quantitatively extracted to a phase rich in Triton X-114 after centrifugation. Methanol acidified with 1 mol/L HNO{sub 3} was added to the surfactant rich phase prior to its analysis by flame atomic absorption spectrometry (FAAS). The concentration of bis((1H-benzo [d] imidazol-2yl)ethyl)sulfane, Triton X-114, pH and amount of surfactant were all optimized. Detection limits (3 SDb/m) of 2.5 and 1.6 ng/mL for Pb{sup 2+} and Zn{sup 2+} along with preconcentration factors of 30 and an enrichment factor of 32 and 48 for Pb{sup 2+}and Zn {sup 2+} ions were obtained, respectively. The proposed cloud point extraction was been successfully applied for the determination of these ions in real samples with complicated matrices such as food and soil samples, with high efficiency. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  4. Cloud point extraction for the determination of copper, nickel and cobalt ions in environmental samples by flame atomic absorption spectrometry.

    Science.gov (United States)

    Ghaedi, M; Shokrollahi, A; Ahmadi, F; Rajabi, H R; Soylak, M

    2008-02-11

    A cloud point extraction procedure was presented for the preconcentration of copper, nickel and cobalt ions in various samples. After complexation with methyl-2-pyridylketone oxime (MPKO) in basic medium, analyte ions are quantitatively extracted to the phase rich in Triton X-114 following centrifugation. 1.0 mol L(-1) HNO(3) nitric acid in methanol was added to the surfactant-rich phase prior to its analysis by flame atomic absorption spectrometry (FAAS). The adopted concentrations for MPKO, Triton X-114 and HNO(3), bath temperature, centrifuge rate and time were optimized. Detection limits (3 SDb/m) of 1.6, 2.1 and 1.9 ng mL(-1) for Cu(2+), Co(2+) and Ni(2+) along with preconcentration factors of 30 and for these ions and enrichment factor of 65, 58 and 67 for Cu(2+), Ni(2+) and Co(2+), respectively. The high efficiency of cloud point extraction to carry out the determination of analytes in complex matrices was demonstrated. The proposed procedure was applied to the analysis of biological, natural and wastewater, soil and blood samples.

  5. Flame Atomic Absorption Determination of Gold Ion in Aqueous Samples after Preconcentration Using 9-Acridinylamine Functionalized γ-Alumina Nanoparticles

    Directory of Open Access Journals (Sweden)

    Mohammad Karimi

    2013-01-01

    Full Text Available A simple and sensitive solid phase extraction utilizing 9-acridinylamine functionalized alumina nanoparticles was developed, and their potential use for preconcentration and subsequent determination of gold by flame atomic absorption spectrometry (FAAS was investigated. A number of parameters, namely, type, concentration, and volume of eluent, pH of the sample solution, flow rate of extraction, and volume of the sample, were evaluated. The effect of a variety of ions on preconcentration and recovery was also investigated. Gold ions were found to be recovered quantitatively at pH 3.0, with 0.1 mol L−1 thiourea in 2 mol L−1 H2SO4 as eluent. The limit of detection (LOD, defined as five times the standard deviation of the blank, was determined to be lower than 13.0 ppb. Under optimum conditions, the accuracy and precision (RSD% of the method were >98.0 and <1.5%, respectively. To gauge its ability in terms of application to real samples, the proposed method was successfully applied for determination of gold concentration in waste water samples and one soil standard material, and satisfactory results were obtained.

  6. [Analysis and comparison of trace elements of herba euphorbiae humifusae in different periods by microwave digestion-atomic absorption spectroscopy].

    Science.gov (United States)

    Xiong, Wei; Cai, Miao-zhen; Wang, Hong; Yu, Rui-peng; Cheng, Cun-gui

    2010-07-01

    Herba euphorbiae humifusae is the dried whole plant of Euphorbia humi fusa Willd. that belongs to euphorbiaceae. In the present paper, the microwave digestion procedure was used to digest herba euphorbiae humifusae collected in different periods, and then flame atomic absorption spectrometry (FAAS) was used to determine the contents of eight kinds of trace elements of herba euphorbiae humifusae in different periods, and the change in the contents of trace elements at different times was studied and analysed. The results showed that of all the trace elements of herba euphorbiae humifusae in different periods, element Fe was the highest in June, element K was in August at the highest level, element Mn reached the highest content in September, elements Na and Ca were dividedly at the highest content in October and November, and in December the highest content elements were Zn, Cu and Mg. In one word, the change of Na and Ca was jumping, while the change of Cu and Zn was comparatively mild. The results provide scientific basis for the time of collection of herba euphorbiae humifusae.

  7. [Investigation of determining strontium in M. nitida Benth. var. hirsutissima. Z. Wei. by flame atomic absorption spectra].

    Science.gov (United States)

    Zhang, Ling; Rao, Zhi-Jun; Guan, Yuan-Yuan; Zhang, Hai-Ming

    2010-12-01

    The present paper is aimed to establish the method of determining the strontium in M. nitida Benth. var. hirsutissima. Z. Wei. by means of air-acetylene flame atomic absorption spectra, and also provide reference for the determination of the strontium in other traditional Chinese medicine. M. Nitida Benthvarhirsutissima Z. Wei. was taken as the object. The authors used nitric-perchloric acid as digestion solution to digest samples by microwave which was controlled by pressure, and used EDTA-2Na as the releasing agent to add in the samples for determining the strontium in M. nitida Benth. var. hirsutissima. Z. Wei. by FAAS. The results showed that the samples were entirely digested by microwave. The working curve was Y = 0.036 5x -0.001 1, r = 0.999 4, the range was 0-1.6 microg x mL(-1), the average recovery rate was 101.5% with RSD 2.04%, and the method detection limit was 0.008 2 microg x mL(-1) (n = 21). It is concluded that this method is simple and accurate. It has high sensitivity and can be effectively used for determining the strontium in this traditional Chinese medicine.

  8. On-line preconcentration of copper as its pyrocatechol violet complex on Chromosorb 105 for flame atomic absorption spectrometric determinations

    Energy Technology Data Exchange (ETDEWEB)

    Buke, Berrin [Chemistry Department, Science and Arts Faculty, Pamukkale University, 20020 Denizli (Turkey); Divrikli, Umit [Chemistry Department, Science and Arts Faculty, Pamukkale University, 20020 Denizli (Turkey)], E-mail: udivrikli@pamukkale.edu.tr; Soylak, Mustafa [Chemistry Department, Science and Arts Faculty, Erciyes University, 38039 Kayseri (Turkey); Elci, Latif [Chemistry Department, Science and Arts Faculty, Pamukkale University, 20020 Denizli (Turkey)

    2009-04-30

    An on-line solid phase extraction method for the preconcentration and determination of Cu(II) by flame atomic absorption spectrometry (FAAS) has been described. It is based on the adsorption of copper(II) ion onto a home made mini column of Chromosorb 105 resin loaded with pyrocatechol violet at the pH range of 5.0-8.0, then eluted with 1 mol L{sup -1} HNO{sub 3}. Several parameters, such as pH of the sample solution, amount of Chromosorb 105 resin, volume of sample and eluent, type of eluent, flow rates of sample and eluent, governing the efficiency and throughput of the method were evaluated. The concentration of the copper ion detected after preconcentration was in agreement with the added amount. At optimized conditions, for 15 min of preconcentration time (30 mL of sample volume), the system achieved a detection limit of 0.02 {mu}g L{sup -1}, with relative standard deviation 1.1% at 0.03 {mu}g mL{sup -1} copper. The present method was found to be applicable to the preconcentration of Cu(II) in natural water samples.

  9. Optimization of microwave assisted digestion procedure for the determination of zinc, copper and nickel in tea samples employing flame atomic absorption spectrometry.

    Science.gov (United States)

    Soylak, Mustafa; Tuzen, Mustafa; Souza, Anderson Santos; das Graças Andrade Korn, Maria; Ferreira, Sérgio Luis Costa

    2007-10-22

    The present paper describes the development of a microwave assisted digestion procedure for the determination of zinc, copper and nickel in tea samples employing flame atomic absorption spectrometry (FAAS). The optimization step was performed using a full factorial design (2(3)) involving the factors: composition of the acid mixture (CMA), microwave power (MP) and radiation time (RT). The experiments of this factorial were carried out using a certified reference material of tea GBW 07605 furnished by National Research Centre for Certified Reference Materials, China, being the metal recoveries considered as response. The relative standard deviations of the method were found below 8% for the three elements. The procedure proposed was used for the determination of copper, zinc and nickel in several samples of tea from Turkey. For 10 tea samples analyzed, the concentration achieved for copper, zinc and nickel varied at 6.4-13.1, 7.0-16.5 and 3.1-5.7 (microg g(-1)), respectively.

  10. Combination of cloud point extraction and flame atomic absorption spectrometry for preconcentration and determination of nickel and manganese ions in water and food samples

    Energy Technology Data Exchange (ETDEWEB)

    Arpa Sahin, Cigdem, E-mail: carpa@hacettepe.edu.tr [Hacettepe University, Chemistry Department, 06800, Beytepe, Ankara (Turkey); Efecinar, Melis; Satiroglu, Nuray [Hacettepe University, Chemistry Department, 06800, Beytepe, Ankara (Turkey)

    2010-04-15

    A simple, rapid, inexpensive, and nonpolluting cloud point extraction (CPE) technique has been improved for the preconcentration and determination of nickel and manganese. After complexation with p-nitrophenylazoresorcinol (Magneson I), the analytes could be competitively extracted in a surfactant octylphenoxy polyethoxyethanol (Triton X-114), prior to determination by flame atomic absorption spectrometry (FAAS). The effects of experimental conditions such as pH, concentration of chelating agent and surfactant, equilibration temperature and time on CPE were studied. Under the optimum conditions, preconcentration of a 25 mL sample solution permitted the detection of 2.7 ng mL{sup -1} Ni{sup 2+} and 2.9 ng mL{sup -1} Mn{sup 2+} with enrichment factors of 17 and 19 for Ni{sup 2+} and Mn{sup 2+}, respectively. The developed method was applied to the determination of trace nickel and manganese in water and food samples with satisfactory results.

  11. Development a novel supramolecular solvent microextraction procedure for copper in environmental samples and its determination by microsampling flame atomic absorption spectrometry.

    Science.gov (United States)

    Yilmaz, Erkan; Soylak, Mustafa

    2014-08-01

    A supramolecular solvent (Ss) made up of reverse micelles of 1-decanol in tetrahydrofuran (THF): water was used for the fast and selective microextraction of Cu(II) prior to its determination by microsampling flame atomic absorption spectrometry (FAAS). Cu(II) was complexed with dimethyl dithiocarbamate (DMDC) to obtain hydrophobic complex and extracted to supramolecular solvent phase. The influences of some analytical parameters including pH, type and volume of supramolecular solvent, amount of complexing agent, ultrasonication and centrifuge time and sample volume were investigated. The effects of matrix components were also examined. The detection limit (LOD) and the quantification limit (LOQ) were 0.52µg L(-1) and 1.71µg L(-1) respectively. An preconcentration factor was obtained as 60 and the relative standard deviation was copper in food and water samples with satisfactory results.

  12. Evaluation of cadmium, lead, copper, iron and zinc in Turkish dietary vegetable oils and olives using electrothermal and flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Acar, O.

    2012-07-01

    The Cd, Pb, Cu, Fe and Zn contents of some edible vegetable oils (soybean, sunflower, flower, nut, corn and olive) and of olives (olive-1, black, green, black crushed with seeds and green crushed with seeds) were determined and evaluated by an electrothermal atomic absorption spectrometer (ETAAS) using an Sc + Ir + NH{sub 4}H{sub 2}PO{sub 4} chemical modifier mixture and flame atomic absorption spectrometer (FAAS) after microwave digestion. The pyrolysis and atomization temperatures of Cd, Pb and Cu in sample solutions with and without the modifier mixture were investigated. The limits of detection (LOD) for analytes found are 0.1, 0.6, 0.9, 15.0 and 12.0 {mu}g L{sup -}1 for Cd, Cu, Pb, Fe and Zn, respectively. The accuracy of the procedure proposed was confirmed by analyzing bovine liver 1577b standard reference material (SRM) and a spiked sample solution. The results of the analytes found were compared with certified and added values. The relative standard deviations of the analytes found were lower than 7% and the percent of recoveries obtained ranges from 96 to 101%. The Sc + Ir + NH{sub 4}H{sub 2}PO{sub 4} mixture proposed was applied for the determination of Cd, Pb and Cu in oils and olives. The results of analytes found in the samples were compared with international and national food quality guidelines as well as with literature values. (Author) 48 refs.

  13. Non-Dispersive Atomic Absorption System for Engine Health Monitoring Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to design, construct and test a first implementation of a non-dispersive technique for the measurement of atomic absorption in the plumes of liquid rocket...

  14. Investigation of novel rapidly synergistic cloud point extraction pattern for bismuth in water and geological samples coupling with flame atomic absorption spectrometry determination

    Science.gov (United States)

    Wen, Xiaodong; Zhao, Yu; Deng, Qingwen; Ji, Shoulian; Zhao, Xia; Guo, Jie

    2012-04-01

    Rapidly synergistic cloud point extraction (RS-CPE) greatly simplified and accelerated the procedure of traditional cloud point extraction (CPE). In order to expand the application of RS-CPE, this work was carried out after the establishment of the improved extraction technique. The new established extraction method was firstly applied for bismuth extraction and determination coupled with flame atomic absorption spectrometry (FAAS) in this work. The improved RS-CPE was accomplished in the room temperature in 1 min. Non-ionic surfactant Triton X-100 (TX-100) was used as extractant. Octanol worked as cloud point revulsant and synergic reagent. TX-100 has a relatively high cloud point temperature (CPT), which limited its application in CPE. In this work, TX-100 accomplished the RS-CPE procedure in room temperature successfully. The factors influencing RS-CPE, such as concentrations of reagents, pH, conditions of phase separation, effect of environmental temperatures, salt effect and instrumental conditions, were studied systematically. Under the optimal conditions, the limit of detection (LOD) for bismuth was 4.0 μg L-1, with sensitivity enhancement factor (EF) of 43. The proposed method greatly improved the sensitivity of FAAS for the determination of bismuth and was applied to the determination of trace bismuth in real and certified samples with satisfactory analytical results. The proposed method was rapid, simple, and sensitive.

  15. A new cloud point extraction procedure for determination of inorganic antimony species in beverages and biological samples by flame atomic absorption spectrometry.

    Science.gov (United States)

    Altunay, Nail; Gürkan, Ramazan

    2015-05-15

    A new cloud-point extraction (CPE) for the determination of antimony species in biological and beverages samples has been established with flame atomic absorption spectrometry (FAAS). The method is based on the fact that formation of the competitive ion-pairing complex of Sb(III) and Sb(V) with Victoria Pure Blue BO (VPB(+)) at pH 10. The antimony species were individually detected by FAAS. Under the optimized conditions, the calibration range for Sb(V) is 1-250 μg L(-1) with a detection limit of 0.25 μg L(-1) and sensitive enhancement factor of 76.3 while the calibration range for Sb(III) is 10-400 μg L(-1) with a detection limit of 5.15 μg L(-1) and sensitive enhancement factor of 48.3. The precision as a relative standard deviation is in range of 0.24-2.35%. The method was successfully applied to the speciative determination of antimony species in the samples. The validation was verified by analysis of certified reference materials (CRMs).

  16. Preconcentration and determination of iron and copper in spice samples by cloud point extraction and flow injection flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Sahin, Cigdem Arpa, E-mail: carpa@hacettepe.edu.tr [Hacettepe University, Chemistry Department, 06800 Beytepe, Ankara (Turkey); Tokgoez, Ilknur; Bektas, Sema [Hacettepe University, Chemistry Department, 06800 Beytepe, Ankara (Turkey)

    2010-09-15

    A flow injection (FI) cloud point extraction (CPE) method for the determination of iron and copper by flame atomic absorption spectrometer (FAAS) has been improved. The analytes were complexed with 3-amino-7-dimethylamino-2-methylphenazine (Neutral Red, NR) and octylphenoxypolyethoxyethanol (Triton X-114) was added as a surfactant. The micellar solution was heated above 50 {sup o}C and loaded through a column packed with cotton for phase separation. Then the surfactant-rich phase was eluted using 0.05 mol L{sup -1} H{sub 2}SO{sub 4} and the analytes were determined by FAAS. Chemical and flow variables influencing the instrumental and extraction conditions were optimized. Under optimized conditions for 25 mL of preconcentrated solution, the enrichment factors were 98 and 69, the limits of detection (3s) were 0.7 and 0.3 ng mL{sup -1}, the limits of quantification (10s) were 2.2 and 1.0 ng mL{sup -1} for iron and copper, respectively. The relative standard deviation (RSD) for ten replicate measurements of 10 ng mL{sup -1} iron and copper were 2.1% and 1.8%, respectively. The proposed method was successfully applied to determination of iron and copper in spice samples.

  17. Determination of trace copper in water samples by flame atomic absorption spectrometry after preconcentration on a phosphoric acid functionalized cotton chelator

    Directory of Open Access Journals (Sweden)

    XINGYAN LIU

    2008-02-01

    Full Text Available This paper reports the preparation of a phosphorylated cotton chelator (PCC by solid phase esterification of phosphoric acid (PA onto defatted cotton fibres using urea as the catalyst. The synthesized PCC was employed for the preconcentration of copper from water samples prior to its determination by flame atomic absorption spectrometry (FAAS. The preconcentration of copper was studied under both batch and column techniques. The pH range for the quantitative preconcentration of copper was 4.0–7.0. The sorption time required for each sample was less than 30 min by the batch method. The copper sorption capacity of the PCC was found to be 15.3 mg/g at the optimum pH value. Elution with 1.0 mol dm-3 hydrochloric acid was found to be quantitative. Feasible flow rates of the copper solution for quantitative sorption onto the column packed with PCC were 0.5–4.0 ml min-1, whereas the optimum flow rate of the hydrochloric acid solution for desorption was less than 1.5 ml min-1. An 80-fold preconcentration factor could be achieved under the optimum column conditions. The tolerance limits for common metal ions on the preconcentration of copper and the number of times of column reuse were investigated. The proposed method was successfully applied for the preconcentration and determination of trace copper in natural and drinking water samples by FAAS.

  18. Speciation of zinc in low molecular weight proteins of breast milk and infant formulas by size exclusion chromatography/flame atomic absorption spectroscopy.

    Science.gov (United States)

    Bermejo, P; Peña, E M; Fompedriña, D; Domínguez, R; Bermejo, A; Cocho, J A; Fernández, J R; Fraga, J M

    2001-01-01

    Size exclusion chromatography (SEC) and flame atomic absorption spectroscopy (FAAS) were used for the separation of metal-containing species in milk whey. After milk ultracentrifugation, the sample was injected into a TSK-Gel G2000 glass column and eluted with 0.2M NH4NO3-NH3, pH 6.7. Low molecular weight proteins were fractionated, and the fractions were characterized by molecular weight. Zinc distributions were obtained by FAAS using a high performance nebulizer. The method was very sensitive (limit of detection = 2.6 x 10(-3) microg/mL; limit of quantitation = 8.9 x 10(-3) microg/mL) and precise (RSDs < or =10%). This method was applied to the determination of Zn in binding compounds in breast milk whey and in commercial cow's milk-based formulas. Distribution patterns were different. The presence of Zn in most fractions in breast milk was most significant, whereas in infant formulas Zn was detected only in fractions of molecular weight <5 kDa and in the highest molecular weight peak.

  19. Determination of β-lactam Antibiotics in Pharmaceutical Preparations by Uv-visible Spectrophotometry Atomic Absorption and High Performance Liquid Chromatography

    Directory of Open Access Journals (Sweden)

    *A. J. Abdulghani

    2012-09-01

    Full Text Available The determination amoxicillin, ampicillin and cephalexin was studied by complexation of the antibiotics with Au(III and Hg(II ions in bulk and pharmaceutical preparations using uv-visible spectrophotometry, atomic absorption, and HPLC techniques. Optimum conditions for complex formation were fixed at pH 4 and (2-4 for Au(III and Hg(IIcomplexes respectively, heating temperature at (60 °C and heating time for (10 minute. All complexes were extracted from aqueous solution with benzyl alcohol prior to measurements except in the case of HPLC. The L:M ratios for all complexes were determined and stability constants were calculated using mole ratio method. The Beer's law was obeyed over the concentration range (5-60 and 5-50 µg/ml of antibiotics for Au(III and Hg(II complexes using colorimetric method and (1-25 µg/ml of Au(III for FAAS. The linearity for HPLC method was (10-110 and 10-120 µg/ml respectively. The correlation coefficients (r were (0.9981-0.9997. Generally, the highest sensitivity was recorded by FAAS.

  20. Investigation of novel rapidly synergistic cloud point extraction pattern for bismuth in water and geological samples coupling with flame atomic absorption spectrometry determination.

    Science.gov (United States)

    Wen, Xiaodong; Zhao, Yu; Deng, Qingwen; Ji, Shoulian; Zhao, Xia; Guo, Jie

    2012-04-01

    Rapidly synergistic cloud point extraction (RS-CPE) greatly simplified and accelerated the procedure of traditional cloud point extraction (CPE). In order to expand the application of RS-CPE, this work was carried out after the establishment of the improved extraction technique. The new established extraction method was firstly applied for bismuth extraction and determination coupled with flame atomic absorption spectrometry (FAAS) in this work. The improved RS-CPE was accomplished in the room temperature in 1 min. Non-ionic surfactant Triton X-100 (TX-100) was used as extractant. Octanol worked as cloud point revulsant and synergic reagent. TX-100 has a relatively high cloud point temperature (CPT), which limited its application in CPE. In this work, TX-100 accomplished the RS-CPE procedure in room temperature successfully. The factors influencing RS-CPE, such as concentrations of reagents, pH, conditions of phase separation, effect of environmental temperatures, salt effect and instrumental conditions, were studied systematically. Under the optimal conditions, the limit of detection (LOD) for bismuth was 4.0 μg L(-1), with sensitivity enhancement factor (EF) of 43. The proposed method greatly improved the sensitivity of FAAS for the determination of bismuth and was applied to the determination of trace bismuth in real and certified samples with satisfactory analytical results. The proposed method was rapid, simple, and sensitive.

  1. Preconcentration and determination of copper and cadmium ions with 1,6-bis(2-carboxy aldehyde phenoxy)butane functionalized Amberlite XAD-16 by flame atomic absorption spectrometry.

    Science.gov (United States)

    Oral, Elif V; Dolak, Ibrahim; Temel, Hamdi; Ziyadanogullari, Berrin

    2011-02-15

    A new chelating resin, covalently linked 1,6-bis(2-carboxy aldehyde phenoxy)butane with the Amberlite XAD-16 was synthesized and used for preconcentration of Cu(II) and Cd(II) prior to their determination by flame atomic absorption spectrometry (FAAS). It was characterized by elemental analyses and Fourier Transform Infrared Spectroscopy (FT-IR). Cu(II) and Cd(II) ions were quantitatively preconcentrated on minicolumn loaded with synthesised resin at pH 4.00 and 6.00, respectively. They were eluated with 5 mL of 0.5 mol L(-1) HCl. Recoveries of Cu(II) and Cd(II) were found to be 100±2.15, 100±1.40 (N=5), the limits of detection of Cu(II) and Cd(II) in the determination by FAAS (3s, N=20) were found to be 0.33 and 1.19 μg L(-1), respectively. The effect of foreign ions on the recovery has been investigated. The proposed method has been applied for the determination of Cu(II) and Cd(II) ions to the real samples collected from Tigris river water in Diyarbakir and Elaziğ cities in Turkey. Standard addition method and analysis of the certified reference material (NCS-DC 73350) was employed to check the accuracy of the method.

  2. Vacuum Ultraviolet Absorption Measurements of Atomic Oxygen in a Shock Tube

    Science.gov (United States)

    Meyer, Scott Andrew

    1995-01-01

    The absorption of vacuum ultraviolet light by atomic oxygen has been measured in the Electric Arc-driven Shock Tube (EAST) Facility at NASA-Ames Research Center. This investigation demonstrates the instrumentation required to determine atomic oxygen concentrations from absorption measurements in impulse facilities. A shock wave dissociates molecular oxygen, producing a high temperature sample of atomic oxygen in the shock tube. A probe beam is generated with a Raman-shifted ArF excimer laser. By suitable tuning of the laser, absorption is measured over a range of wavelengths in the region of the atomic line at 130.49 nm. The line shape function is determined from measurements at atomic oxygen densities of 3 x 10(exp 17) and 9 x 10(exp 17)/cu cm. The broadening coefficient for resonance interactions is deduced from this data, and this value is in accord with available theoretical models.

  3. Vacuum Ultraviolet Absorption Measurements of Atomic Oxygen in a Shock Tube

    Science.gov (United States)

    Meyer, Scott Andrew

    1995-01-01

    The absorption of vacuum ultraviolet light by atomic oxygen has been measured in the Electric Arc-driven Shock Tube (EAST) Facility at NASA-Ames Research Center. This investigation demonstrates the instrumentation required to determine atomic oxygen concentrations from absorption measurements in impulse facilities. A shock wave dissociates molecular oxygen, producing a high temperature sample of atomic oxygen in the shock tube. A probe beam is generated with a Raman-shifted ArF excimer laser. By suitable tuning of the laser, absorption is measured over a range of wavelengths in the region of the atomic line at 130.49 nm. The line shape function is determined from measurements at atomic oxygen densities of 3 x 10(exp 17) and 9 x 10(exp 17) cm(exp -3). The broadening coefficient for resonance interactions is deduced from this data, and this value is in accord with available theoretical models.

  4. Theoretical analysis on two-photon absorption spectroscopy in a confined four-level atomic system

    Institute of Scientific and Technical Information of China (English)

    Yuanyuan Li; Jintao Bai; Li Li; Yanpeng Zhang; Xun Hou

    2009-01-01

    We investigate theoretically two-photon absorption spectroscopy modified by a control field in a confined Y-type four-level system. Dicke-narrowing effect occurs both in two-photon absorption lines and the dips of transparency against two-photon absorption due to enhanced contribution of slow atoms. We also find that the suppression and the enhancement of two-photon absorption can be modified by changing the strength of the control field and the detuning of three laser fields. This control of two-photon absorption may have some applications in information processing and optical devices.

  5. Understanding the mechanism of H atom absorption in the Pd(1 1 0) surface

    Energy Technology Data Exchange (ETDEWEB)

    Padama, Allan Abraham B. [Institute of Mathematical Sciences and Physics, College of Arts and Sciences, University of the Philippines Los Baños, Los Baños, Laguna 4031 (Philippines); Kasai, Hideaki, E-mail: kasai@dyn.ap.eg.osaka-u.ac.jp [Department of Applied Physics, Osaka University, Suita, Osaka 565-0871 (Japan); Center for Atomic and Molecular Technologies, Osaka University, Suita, Osaka 565-0871 (Japan); Center for Continuing Professional Development, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871 (Japan)

    2015-10-05

    Highlights: • This study elucidates the absorption of H in Pd(1 1 0) (1 × 2) missing-row surface. • Electronic structure depicts the stronger adsorption on ridge than on trough site. • The geometry of missing-row Pd(1 1 0) allows Pd atoms to accommodate H and H{sub 2}. • Assisted absorption is facilitated by the repulsion between H atoms. - Abstract: The underlying mechanism of H atom absorption in the Pd(1 1 0) (1 × 2) missing-row reconstructed surface is investigated by performing density functional theory based calculations. The stronger binding energy of H on ridge than on trough site of the missing-row surface is due to the more pronounced creation of derived bonding state as had been depicted from the electronic structure of the system. Hydrogen absorption takes place with the involvement of other incoming H atoms through an assisted absorption process that is facilitated by the repulsion between the incoming H and the absorbing H. The geometry of the missing-row surface enables the Pd atoms to accommodate the H atoms efficiently leading to H absorption as well as H{sub 2} dissociation.

  6. Bioavailability study of calcium sandoz-250 by atomic absorption spectroscopy in albino rats

    OpenAIRE

    Patel, Bimalkumar N.; Krishnaveni, N.; Jivani, Nurrrudin P.; Khodakiya, Akruti S.; Khodakiya, Moorti S.; Parida, Saswat K.

    2014-01-01

    Background: Calcium sandoz-250 is an Ayurvedic calcium supplement, containing Khatika Churna. Bioavailability study of the formulation is essential for estimation of peak plasma concentration (C max), time to C max and rate of absorption. Aim: To evaluate the absorption parameters of calcium sandoz-250 in albino rats by atomic absorption spectroscopic (AAS) method. Materials and Methods: Study was carried out as a single dose, open-label, randomized study. Estimation of calcium was carried ou...

  7. Comparison between EDXRF and FAAS for Zn determination in terrestrial molluscs

    Energy Technology Data Exchange (ETDEWEB)

    Melo, Julyanne T.B.; Cantinha, Rebeca S.; Santos, Mariana L.O.; Santos, Katarine M.B.; Franca, Elvis J., E-mail: julyanne.melo@ufpe.br, E-mail: rebecanuclear@gmail.com, E-mail: marianasantos_ufpe@hotmail.com, E-mail: katarine.mizan@gmail.com, E-mail: ejfranca@cnen.gov.br [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil); Melo, Ana M.M.A., E-mail: amdemelo@hotmail.com [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Departamento de Biofisica e Radiobiologia

    2015-07-01

    Even with the most advanced analytical techniques, achieving the true values of a given analyte in a sample cannot be an easy task. Energy Dispersive X-Ray Fluorescence (EDXRF) and Flame Atomic Absorption Spectrometry (FAAS) have been widely used for analysis of the chemical composition of biological matrices in environmental studies. However, depending on the sample matrix, a combination of techniques could be needed for the correct determination of the analyte. Zinc distribution in Littoraria angulifera and Melampus coffea is quite dependent on the environment, so that, diverse methods could be necessary to evaluate the chemical composition of these mollusks. This study aimed at the comparison between EDXRF and FAAS techniques for determining Zn in the soft tissues of terrestrial mollusks. The animals were collected in three mangroves in the State of Pernambuco, Brazil. After shell removal, tissues were lyophilized and milled in a mortar. Test portions of 500 mg were analyzed by EDXRF, followed by chemical treatment for FAAS analysis. For the quality of the analytical procedure, the standard reference material SRM 2976 Mussel Tissue was analyzed together with the samples. The results for the analysis of the certified reference material SRM 2976 indicated the quality of the analytical procedure for both techniques. Adjusted-R{sup 2} between EDXRF and FAAS results was 0.95, indicating a good equivalence of Zn determination by both techniques. However, some improvement of EDXRF determination could be necessary because of the tendency of lower results compared to FAAS, probably related to spectral interferences during the analysis. (author)

  8. Atomic structure of machined semiconducting chips: An x-ray absorption spectroscopy study

    Energy Technology Data Exchange (ETDEWEB)

    Paesler, M.; Sayers, D.

    1988-12-01

    X-ray absorption spectroscopy (XAS) has been used to examine the atomic structure of chips of germanium that were produced by single point diamond machining. It is demonstrated that although the local (nearest neighbor) atomic structure is experimentally quite similar to that of single crystal specimens information from more distant atoms indicates the presence of considerable stress. An outline of the technique is given and the strength of XAS in studying the machining process is demonstrated.

  9. Optical pumping effect in absorption imaging of F=1 atomic gases

    CERN Document Server

    Kim, Sooshin; Noh, Heung-Ryoul; Shin, Y

    2016-01-01

    We report our study of the optical pumping effect in absorption imaging of $^{23}$Na atoms in the $F=1$ hyperfine spin states. Solving a set of rate equations for the spin populations under a probe beam, we obtain an analytic expression for the optical signal of the $F=1$ absorption imaging. Furthermore, we verify the result by measuring the absorption spectra of $^{23}$Na Bose-Einstein condensates prepared in various spin states with different probe beam pulse durations. The analytic result can be used in quantitative analysis of $F=1$ spinor condensate imaging and readily applied to other alkali atoms with $I=3/2$ nuclear spin such as $^{87}$Rb.

  10. Reduction of interference fringes in absorption imaging of cold atom cloud using eigenface method

    Institute of Scientific and Technical Information of China (English)

    Xiaolin Li; Min Ke; Bo Yan; Yuzhu Wang

    2007-01-01

    Eigenface method used in face recognition is introduced to reduce the pattern of interference fringes appearing in the absorption image of cold rubidium atom cloud trapped by an atom chip. The standard method for processing the absorption image is proposed, and the origin of the interference fringes is analyzed. Compared with the standard processing method which uses only one reference image, we take advantage of fifty reference images and reconstruct a new reference image which is more similar to the absorption image than all of the fifty original reference images. Then obvious reduction of interference fringes can be obtained.

  11. Determination of cadmium in biodiesel using microemulsion and electrothermal atomization atomic absorption spectrometry.

    Science.gov (United States)

    Lima, Adriana S; Silva, Deise G; Teixeira, Leonardo S G

    2015-01-01

    This work aimed to prepare biodiesel microemulsions for the subsequent quantification of cadmium via graphite furnace atomic absorption spectrometry (GFAAS). The biodiesel samples were prepared using n-propanol as an emulsifier, 10% (v/v) nitric acid as the aqueous phase, and biodiesel. Pseudoternary phase diagrams were constructed to determine the microemulsion region with the specified components. The optimized conditions for microemulsion formation were 57.6% (v/v) n-propanol, 21.2% (v/v) biodiesel, and 21.2% (v/v) nitric acid solution. The stability of the microemulsified system was investigated using aqueous and organic standards, and the system was found to be stable for at least 240 min. The applied pyrolysis and atomization temperatures were 800 and 2000 °C, respectively, and 5 μg of aluminum was used as the chemical modifier. The obtained limits of detection and quantification were 0.2 and 0.5 μg kg(-1), respectively, and the characteristic mass was 1.6 pg. The precision, expressed as the relative standard deviation (% R.S.D., n = 10), was 2.5% for a sample with a cadmium concentration of 6.5 μg kg(-1). The accuracy was determined from addition and recovery experiments, with results varying from 93 to 108% recovery. This study demonstrates that the proposed method based on the use of a microemulsion formation in sample preparation can be applied as an efficient alternative for the determination of cadmium in biodiesel by GFAAS. Cadmium determination in biodiesel samples of different origins (soybean, corn, cotton, and sunflower) was evaluated after acid digestion using the inductively coupled plasma-mass spectrometry (ICP-MS) technique, and the obtained results were compared to the results obtained using the proposed method. The paired t test (95% confidence level) did not show significant differences. The concentrations of cadmium found ranged from 5.3 to 8.0 μg kg(-1).

  12. Gold volatile species atomization and preconcentration in quartz devices for atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Arslan, Yasin [Institute of Analytical Chemistry of the ASCR, v. v. i., Veveří 97, 602 00 Brno (Czech Republic); Mehmet Akif Ersoy University, Faculty of Arts & Sciences, Chemistry Department, 15030 Burdur (Turkey); Musil, Stanislav; Matoušek, Tomáš; Kratzer, Jan [Institute of Analytical Chemistry of the ASCR, v. v. i., Veveří 97, 602 00 Brno (Czech Republic); Dědina, Jiří, E-mail: dedina@biomed.cas.cz [Institute of Analytical Chemistry of the ASCR, v. v. i., Veveří 97, 602 00 Brno (Czech Republic)

    2015-01-01

    The on-line atomization of gold volatile species was studied and the results were compared with thermodynamic calculations in several quartz atomizers, namely: diffusion flame, flame-in-gas-shield, flame-in-plain-tube, externally heated T-tube and externally heated flame-in-T-tube. Atomization mechanism in the explored devices is proposed, where volatile species are converted to thermodynamically stable AuH at elevated temperature over 500 °C and then atomized by an interaction with a cloud of hydrogen radicals. Because of its inherent simplicity and robustness, diffusion flame was employed as a reference atomizer. It yielded atomization efficiency of 70 to 100% and a very good long time reproducibility of peak area sensitivity: 1.6 to 1.8 s μg{sup −1}. Six and eleven times higher sensitivity, respectively, was provided by atomizers with longer light paths in the observation volume, i.e. externally heated T-tube and externally heated flame-in-T-tube. The latter one, offering limit of detection below 0.01 μg ml{sup −1}, appeared as the most prospective for on-line atomization. Insight into the mechanism of atomization of gold volatile species, into the fate of free atoms and into subsequent analyte transfer allowed to assess possibilities of in-atomizer preconcentration of gold volatile species: it is unfeasible with quartz atomizers but a sapphire tube atomizer could be useful in this respect. - Highlights: • On-line atomization of gold volatile species for AAS in quartz devices was studied. • Atomization mechanism was proposed and atomization efficiency was estimated. • Possibilities of in-atomizer preconcentration of gold volatile species were assessed.

  13. Application of dual-cloud point extraction for the trace levels of copper in serum of different viral hepatitis patients by flame atomic absorption spectrometry: A multivariate study

    Science.gov (United States)

    Arain, Salma Aslam; Kazi, Tasneem G.; Afridi, Hassan Imran; Abbasi, Abdul Rasool; Panhwar, Abdul Haleem; Naeemullah; Shanker, Bhawani; Arain, Mohammad Balal

    2014-12-01

    An efficient, innovative preconcentration method, dual-cloud point extraction (d-CPE) has been developed for the extraction and preconcentration of copper (Cu2+) in serum samples of different viral hepatitis patients prior to couple with flame atomic absorption spectrometry (FAAS). The d-CPE procedure was based on forming complexes of elemental ions with complexing reagent 1-(2-pyridylazo)-2-naphthol (PAN), and subsequent entrapping the complexes in nonionic surfactant (Triton X-114). Then the surfactant rich phase containing the metal complexes was treated with aqueous nitric acid solution, and metal ions were back extracted into the aqueous phase, as second cloud point extraction stage, and finally determined by flame atomic absorption spectrometry using conventional nebulization. The multivariate strategy was applied to estimate the optimum values of experimental variables for the recovery of Cu2+ using d-CPE. In optimum experimental conditions, the limit of detection and the enrichment factor were 0.046 μg L-1 and 78, respectively. The validity and accuracy of proposed method were checked by analysis of Cu2+ in certified sample of serum (CRM) by d-CPE and conventional CPE procedure on same CRM. The proposed method was successfully applied to the determination of Cu2+ in serum samples of different viral hepatitis patients and healthy controls.

  14. Application of dual-cloud point extraction for the trace levels of copper in serum of different viral hepatitis patients by flame atomic absorption spectrometry: a multivariate study.

    Science.gov (United States)

    Arain, Salma Aslam; Kazi, Tasneem G; Afridi, Hassan Imran; Abbasi, Abdul Rasool; Panhwar, Abdul Haleem; Naeemullah; Shanker, Bhawani; Arain, Mohammad Balal

    2014-12-10

    An efficient, innovative preconcentration method, dual-cloud point extraction (d-CPE) has been developed for the extraction and preconcentration of copper (Cu(2+)) in serum samples of different viral hepatitis patients prior to couple with flame atomic absorption spectrometry (FAAS). The d-CPE procedure was based on forming complexes of elemental ions with complexing reagent 1-(2-pyridylazo)-2-naphthol (PAN), and subsequent entrapping the complexes in nonionic surfactant (Triton X-114). Then the surfactant rich phase containing the metal complexes was treated with aqueous nitric acid solution, and metal ions were back extracted into the aqueous phase, as second cloud point extraction stage, and finally determined by flame atomic absorption spectrometry using conventional nebulization. The multivariate strategy was applied to estimate the optimum values of experimental variables for the recovery of Cu(2+) using d-CPE. In optimum experimental conditions, the limit of detection and the enrichment factor were 0.046μgL(-1) and 78, respectively. The validity and accuracy of proposed method were checked by analysis of Cu(2+) in certified sample of serum (CRM) by d-CPE and conventional CPE procedure on same CRM. The proposed method was successfully applied to the determination of Cu(2+) in serum samples of different viral hepatitis patients and healthy controls.

  15. Graphene for Preconcentration of Trace Amounts of Ni in Water and Paraffin-Embedded Tissues from Liver Loggerhead Turtles Specimens Prior to flame Atomic Absorption Spectrometry

    Directory of Open Access Journals (Sweden)

    Hanie Arbabi Rashid

    2014-03-01

    Full Text Available A new sensitive and simple method was developed for the preconcentration of trace amounts of Ni using 1-(2-pyridylazo-2-naphthol (PAN as chelating reagent prior to its determination by flame atomic absorption spectrometry. The proposed method is based on the uti- lization of a column packed with graphene as sorbent. Several effective parameters on the extraction and complex formation were selected and optimized. Under optimum conditions, the calibration graph was linear in the concentration range of 5.0–240.0 µg L-1 with a detection limit of 0.36 µg L-1. The relative standard deviation for ten replicate measurements of 20.0 and 100.0 µg L-1 of Ni were 3.45 and 3.18%, respectively. Comparative studies showed that graphene is superior to other adsorbents including C18 silica, graphitic carbon, and single- and multi-walled carbon nanotubes for the extraction of Ni. In the present study, we report the application of preconcentration techniques still continues increasingly for trace metal determinations by flame atomic absorption spectrometry (FAAS for quantification of Ni in Formalin-fixed paraffin-embedded (FFPE tissues from Liver loggerhead turtles. The proposed method was successfully applied in the analysis of four real environmental water samples. Good spiked recoveries over the range of 95.8–102.6% were obtained.

  16. Atomic absorption determination of tin in foods: collaborative study.

    Science.gov (United States)

    Elkins, E R; Sulek, A

    1979-09-01

    Samples of green beans, applesauce, and a fruit juice were fortified with tin at 3 levels. Collaborators were asked to digest the samples, using HNO3-H2SO4, add methanol to enhance the absorption signal, and aspirate directly, using a nitrous oxide-acetylene flame. Results were received from 8 laboratories including 4 from Europe. However, only 6 laboratories used the prescribed methodology. All results were considered acceptable. The method has been adopted as interim official first action.

  17. Absorption Spectra of a Three-Level Atom Embedded in a PBG Reservoir

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ke; ZHANG Han-Zhuang

    2007-01-01

    We introduce the 'decay rate' terms into the density matrix equations of an atom embedded in a photonic band gap (PSG)reservoir successfully.By utilizing the master equations,the probe absorption spectra and the refractivity properties of a three-level atom in the PBG reservoir are obtained.The interaction between the atom and the PBG reservoir as well as the effects of the quantum interference on the absorption of the atom has also been taken into account.It is interesting that two different types of the anomalous dispersion relations of refractivity are exhibited in one dispersion line.The methodology used here can be applied to theoretical investigation of quantum interference effects of other atomic models embedded in a PBG reservoir.

  18. Flameless Atomic Absorption Spectroscopy: Effects of Nitrates and Sulfates.

    Science.gov (United States)

    1980-05-01

    oxide by graphite followed by sublimation of the metal. Frech and Cedergren investigated high temperature equilibria in graphite furnace atomizers. 1 4...Acta, 72, 49 (1974). 13. R.E. Sturgeon, C.L. Chakrabarti, and C.H. Langford, Anal. Chem., 48, 1792 (1976). 14. W. Frech and A. Cedergren , Anal. Chim...Acta, 82, 83 (1976). 15. W. Frech, Anal. Chim. Acta, 77, 43 (1975). 16. W. Frech and A. Cedergren , Anal. Chim. Acta, 88, 57 (1977). CHAPTER III

  19. Dielectric barrier discharge plasma atomizer for hydride generation atomic absorption spectrometry—Performance evaluation for selenium

    Energy Technology Data Exchange (ETDEWEB)

    Duben, Ondřej [Institute of Analytical Chemistry of the CAS, v.v.i., Veveří 97, CZ-602 00 Brno (Czech Republic); Faculty of Science, Department of Analytical Chemistry, Charles University in Prague, Hlavova 8, Prague, CZ 128 43 Czech Republic (Czech Republic); Boušek, Jaroslav [Faculty of Electrical Engineering and Communications, Brno University of Technology, Technická 1058/10, 61600 Brno (Czech Republic); Dědina, Jiří [Institute of Analytical Chemistry of the CAS, v.v.i., Veveří 97, CZ-602 00 Brno (Czech Republic); Kratzer, Jan, E-mail: jkratzer@biomed.cas.cz [Institute of Analytical Chemistry of the CAS, v.v.i., Veveří 97, CZ-602 00 Brno (Czech Republic)

    2015-09-01

    Atomization of selenium hydride in a quartz dielectric barrier discharge (DBD) atomizer was optimized and its performance was compared to that of the externally heated quartz multiatomizer. Argon was found as the best DBD discharge gas employing a flow rate of 75 ml min{sup −1} Ar while the DBD power was optimized at 14 W. The detection limits reached 0.24 ng ml{sup −1} Se in the DBD and 0.15 ng ml{sup −1} Se in the multiatomizer. The tolerance of DBD to interferences is even better than with the multiatomizer. - Highlights: • SeH{sub 2} atomization in a dielectric barrier discharge (DBD) was optimized for AAS. • Atomizer performance was compared for DBD and externally heated quartz atomizer. • Detection limits were quantified and interferences were studied in both atomizers. • Atomization efficiency in the DBD was estimated.

  20. Chlorine Analysis by Diode Laser Atomic Absorption Spectrometry

    Institute of Scientific and Technical Information of China (English)

    Joachim Koch; Aleksandr Zybin; Kay Niemax

    2000-01-01

    The general characteristics of Diode Laser Absorption Spectrometry (DLAAS) in low pressure plasmas particulary with respect to the detection of non-metals are comprehensively recapitulated and discussed. Furthermore, a detector, which is based on DLAAS in a microwave-induced low pressure plasma as an alternative technique for halogene-specific analysis of volatile compounds and polymeric matrices is described. The analytical capability of the technique is demonstrated on the chlorine-specific analysis of ablated polymer fragments as well as gas chromatographically separated hydrocarbons. Since the measurements were carried out by means of a balanced-heterodyne detection scheme, different technical noise contributions, such as laser excess and RAM noise could efficiently be suppressed and the registered absorption was limited only by the principal shot noise. Thus, in the case of the polymer analysis a chlorine-specific absolute detection limit of 10 pg could be achieved. Furthermore, fundamental investigations concerning the influence of hydrocarbons on the dissociation capability of the microwave induced plasma were performed. For this purpose, the carbon-, chlorine-and hydrogen-specific stoichiometry of the compounds were empirically determined. Deviations from the exspected proportions were found to be insignificant, implying the possibility of internal standardization relative to the response of a reference sample.

  1. Determination of antimony by using tungsten trap atomic absorption spectrometry

    Science.gov (United States)

    Titretir, Serap; Kendüzler, Erdal; Arslan, Yasin; Kula, İbrahim; Bakırdere, Sezgin; Ataman, O. Yavuz.

    2008-08-01

    An electrically heated tungsten coil was used as a trap in the determination of antimony. The technique consists of three steps. Initially, SbH 3 is formed by hydride generation procedure; then the analyte species in vapor form are transported to W-coil trap heated at 370 °C. Following the preconcentration step, the trap is heated to 895 °C; analyte species are revolatilized and transported to the flame-heated quartz atom cell where atomization and the formation of signal take place. The experimental parameters were optimized both for trap and no-trap studies. The most important experimental parameters are concentrations of HCl and NaBH 4 solutions, H 2 and Ar gas flow rates, and collection and revolatilization temperatures of W-coil. Accuracy was tested using a certified reference material, waste water EU-L-1. Limit of detection for the system is 16 ng l - 1 using a sample of 36 ml collected in 4.0 min. Enhancement factor in sensitivity was 17.

  2. Determination of antimony by using tungsten trap atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Titretir, Serap [Department of Chemistry, Inoenue University, 44065 Malatya (Turkey); Kenduezler, Erdal [Department of Primary Education, Faculty of Education, Ahi Evran University, 40100 Kirsehir (Turkey); Arslan, Yasin [Department of Chemistry, Middle East Technical University, 06531 Ankara (Turkey); Department of Chemistry, Atatuerk University, 25240 Erzurum (Turkey); Kula, Ibrahim [Department of Chemistry, Mugla University, 48000 Mugla (Turkey); Bakirdere, Sezgin [Department of Chemistry, Middle East Technical University, 06531 Ankara (Turkey); Department of Chemistry, Zonguldak Karaelmas University, 67100 Zonguldak (Turkey); Ataman, O. Yavuz. [Department of Chemistry, Middle East Technical University, 06531 Ankara (Turkey)], E-mail: ataman@metu.edu.tr

    2008-08-15

    An electrically heated tungsten coil was used as a trap in the determination of antimony. The technique consists of three steps. Initially, SbH{sub 3} is formed by hydride generation procedure; then the analyte species in vapor form are transported to W-coil trap heated at 370 deg. C. Following the preconcentration step, the trap is heated to 895 deg. C; analyte species are revolatilized and transported to the flame-heated quartz atom cell where atomization and the formation of signal take place. The experimental parameters were optimized both for trap and no-trap studies. The most important experimental parameters are concentrations of HCl and NaBH{sub 4} solutions, H{sub 2} and Ar gas flow rates, and collection and revolatilization temperatures of W-coil. Accuracy was tested using a certified reference material, waste water EU-L-1. Limit of detection for the system is 16 ng l{sup -1} using a sample of 36 ml collected in 4.0 min. Enhancement factor in sensitivity was 17.

  3. Entanglement-preserving absorption of single SPDC photons by a single atom

    CERN Document Server

    Huwer, J; Piro, N; Schug, M; Dubin, F; Eschner, J

    2011-01-01

    We study the controlled interaction between a single trapped Ca40+ ion and single photons belonging to entangled photon pairs. The ion is prepared as a polarization-sensitive single-photon absorber; the absorption of one photon from a pair is marked by a quantum jump of the atomic state and heralded by the coincident detection of the entangled partner photon. For three polarization basis settings of absorption and detection of the herald, we find maximum coincidences always for orthogonal polarizations. Tomographic reconstruction of the biphoton quantum state from the absorption-herald coincidences reveals 93% overlap with the maximally entangled state. This proves that the polarization entanglement shared by the photon pair is preserved in the absorption process and converted to transient photon-atom entanglement.

  4. Infrared absorption on a complex comprising three equivalent hydrogen atoms in ZnO

    Science.gov (United States)

    Herklotz, F.; Hupfer, A.; Johansen, K. M.; Svensson, B. G.; Koch, S. G.; Lavrov, E. V.

    2015-10-01

    A hydrogen-related defect in ZnO which causes two broad IR absorption bands at 3303 and 3321 cm-1 is studied by means of infrared absorption spectroscopy and first-principles theory. In deuterated samples, the defect reveals two sharp absorption lines at 2466 and 2488 cm-1 accompanied by weaker sidebands at 2462 and 2480 cm-1. Isotope substitution experiments with varying concentrations of H and D together with polarization-sensitive measurements strongly suggest that these IR absorption lines are due to stretch local vibrational modes of a defect comprising three equivalent hydrogen atoms. The zinc vacancy decorated by three hydrogen atoms, VZnH3 , and ammonia trapped at the zinc vacancy, (NH3)Zn, are discussed as a possible origin for the complex.

  5. Cloud Point Extraction and Flame Atomic Absorption Spectrometric Determination of Lead, Cadmium and Palladium in Some Food and Biological Samples

    Directory of Open Access Journals (Sweden)

    M. Soylak

    2011-12-01

    Full Text Available The proposed method is based on the complexation of the Pb2+, Cd2+ and Pd2+ ions with 3-(1-(1-H-Indol-3-Yl-3-phenylallyl-1H-indole (IPAI at pH 8.0 in the presence of Triton X-114. The phase separation occured when micellar solution was heated at 55 ◦C. The surfactant-rich phase, diluted to 0.5 mL via 1.0 mol L−1 nitric acid in methanol was directly introduced into the nebulizer of the flame atomic absorption spectrometry (FAAS. Influence of variables such as pH, amount of ligand and Triton X-114, heating time and temperature were evaluated and optimized. The optimized enhancement factors for Pb2+, Cd2+ and Pd2+ ions were 22, 33 and 23, respectively and the detection limit (DLs was between of 1.6–2.6 µgL−1. The relative standard deviation (RSD of each ion was found to be less than 4.6% at 100 µgL−1. In addition, the calibration graphs were linear in the range of 0.01-0.22 μg mL−1 for Cd2+ ion, 0.018-0.26 μg mL−1 for Pb2+ ion and 0.02-0.27 μg mL−1 for Pd2+ ion with the correlation coefficients in the range of 0.995–0.999.

  6. Preconcentration procedure using cloud point extraction in the presence of electrolyte for cadmium determination by flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Melo Coelho, Luciana [Departamento de Quimica Analitica, Universidade Estadual de Campinas (Unicamp), Cidade Universitaria ' Zeferino Vaz' , 13084-971, Campinas, Sao Paulo (Brazil); Arruda, Marco Aurelio Zezzi [Departamento de Quimica Analitica, Universidade Estadual de Campinas (Unicamp), Cidade Universitaria ' Zeferino Vaz' , 13084-971, Campinas, Sao Paulo (Brazil)]. E-mail: zezzi@iqm.unicamp.br

    2005-06-30

    This paper describes a micelle-mediated phase separation in the presence of electrolyte as a preconcentration method for cadmium determination by flame atomic absorption spectrometry (FAAS). Cadmium was complexed with ammonium O,O-diethyldithiophosphate (DDTP) in an acidic medium (0.32 mol l{sup -} {sup 1} HCl) using Triton X-114 as surfactant and quantitatively extracted into a small volume (about 20 {mu}l) of the surfactant-rich phase after centrifugation. The chemical variables that affect the cloud point extraction, such as complexing time (0-20 min), Triton X114 concentration (0.043-0.87% w/v) and complexing agent concentration (0.01-0.1 mol l{sup -} {sup 1}), were investigated. The cloud point is formed in the presence of NaCl at room temperature (25 deg. C), and the electrolyte concentration (0.5-5% w/v) was also investigated. Under optimized conditions, only 8 ml of sample was used in the presence of 0.043% w/v Triton X-114 and 1% (w/v) NaCl. This method permitted limits of detection and quantification of 0.9 {mu}g l{sup -} {sup 1} and 2.9 {mu}g l{sup -} {sup 1} Cd, respectively, and a linear calibration range from 3 to 400 {mu}g l{sup -} {sup 1} Cd. The proposed method was applied to Cd determination in physiological solutions (containing 0.9% (w/v) of NaCl), mineral water, lake water and cigarette samples (tobacco)

  7. A sapphire tube atomizer for on-line atomization and in situ collection of bismuthine for atomic absorption spectrometry

    OpenAIRE

    Musil, S. (Stanislav); Dědina, J. (Jiří)

    2013-01-01

    Sapphire was tested as a new material for volatile species atomizers and bismuthine was chosen as a convenient model for volatile species. Its performance was compared with a quartz atomizer in both modes of operation - on-line atomization versus in situ collection.

  8. Observing random walks of atoms in buffer gas through resonant light absorption

    CERN Document Server

    Aoki, Kenichiro

    2016-01-01

    Using resonant light absorption, random walk motions of rubidium atoms in nitrogen buffer gas are observed directly. The transmitted light intensity through atomic vapor is measured and its spectrum is obtained, down to orders of magnitude below the shot noise level to detect fluctuations caused by atomic motions. To understand the measured spectra, the spectrum for atoms performing random walks in a gaussian light beam is computed and its analytical form is obtained. The spectrum has $1/f^2$ ($f$: frequency) behavior at higher frequencies, crossing over to a different, but well defined behavior at lower frequencies. The properties of this theoretical spectrum agree excellently with the measured spectrum. This understanding also enables us to obtain the diffusion constant, the photon cross section of atoms in buffer gas and the atomic number density, from a single spectral measurement. We further discuss other possible applications of our experimental method and analysis.

  9. Direct determination of selenoproteins in polyvinylidene difluoride membranes by electrothermal atomic absorption spectrometry

    DEFF Research Database (Denmark)

    Sidenius, U; Gammelgaard, Bente

    2000-01-01

    A method for the direct determination of selenoproteins in plastic membranes after protein separation by gel electrophoresis was developed. Quantification was based on the determination of the selenium content of the proteins by electrothermal atomic absorption spectrometry (ET-AAS) after manual...... were excised and chemical modifier was added on top of the excised membrane prior to atomic absorption measurement. Acceptable linearity was achieved in the range 2-10 ng Se, corresponding to selenium concentrations close to 1 mg/L, when aqueous solutions of selenomethionine standard as well...

  10. The Application of Atomic Absorption Spectroscopy and Optical Microscopy to the Characterization of Sized Airborne Particulate in Dayton, Ohio.

    Science.gov (United States)

    1978-01-01

    PERIOD COVERED " AneT Appication of Atomic Absorption Spectroscopy ’ and Optical Microscopy to the Characterization of THESIS/DISSERTATION 4 Sized...1978 U I HEREBY REC04MEND THAT THE THESIS PREPARED ’NDER MY SUPERVISION BY Lorelei Ann Krebs ENTITLED The Application of Atomic Absorption Spectroscopy and...acid and diluted with distilled water in a 25 milliliter volumetric flask. Atomic absorption . spectroscopy was used to analyze the solutions for

  11. Determination of vanadium in food and traditional Chinese medicine by graphite furnace atomic absorption spectroscopy

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Various experimental conditions were described for the vanadium determination by graphite furnace atomic ab-sorption spectroscopy (GFAAS). The experiments showed that when atomization took place under the conditions where thecombination of a pyrolytic coating graphite tube and fast raising temperature were used and the temperature was stable, thesignal peak shapes could be improved, the sensitivity was enhanced, and the memory effect was removed. The vanadium infood and traditional Chinese medicinal herbs can be accurately determined using the standard curve method.

  12. Padronização interna em espectrometria de absorção atômica Internal standardization in atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    Kelly G. Fernandes

    2003-03-01

    Full Text Available This paper describes a review on internal standardization in atomic absorption spectrometry with emphasis to the systematic and random errors in atomic absorption spectrometry and applications of internal standardization in flame atomic absorption spectrometry and electrothermal atomic absorption spectrometry. The rules for selecting an element as internal standard, limitations of the method, and some comments about the application of internal standardization in atomic absorption spectrometry and the future of this compensation strategy are critically discussed.

  13. Absorption spectroscopy of cold caesium atoms confined in a magneto-optical trap

    Institute of Scientific and Technical Information of China (English)

    Yan Shu-Bin; Liu Tao; Geng Tao; Zhang Tian-Cai; Peng Kun-Chi; Wang Jun-Min

    2004-01-01

    Absorption spectra of cold caesium atoms confined in a magneto-optical trap are measured around D2 line at 852nm with a weak probe beam. Absorption reduction dip due to electromagnetically induced transparency (EIT)effect induced by the cooling/trapping field in a V-type three-level system and a gain peak near the cycling transition are clearly observed. Several mechanisms mixed with EIT effect in a normal V-type three-level system are briefly discussed. A simple theoretical analysis based on a dressed-state model is presented for interpretation of the absorption spectra.

  14. Determination of zinc in edible oils by flow injection FAAS after extraction induced by emulsion breaking procedure.

    Science.gov (United States)

    Bakircioglu, Dilek; Topraksever, Nukte; Kurtulus, Yasemin Bakircioglu

    2014-05-15

    A new procedure using extraction induced by emulsion breaking (EIEB) procedure has been developed for extraction/preconcentration of zinc in various edible oils (canola oil, corn oil, hazelnut oil, olive oil, and sunflower oil) prior to its determination by the single line flow injection (FI) flame atomic absorption spectrometry (FAAS). Several parameters affecting the extraction efficiency of the procedure were investigated including the type and concentrations of surfactant, the concentration of HNO3, and the other operational conditions (emulsion breaking time and temperature). The limits of detection of 1.1 and 1.0 μg L(-1) were observed for zinc when aqueous standard and oil-based standards were added to the emulsions for calibration, respectively. The proposed procedure of combining EIEB and single line FI-FAAS can be regarded as a new procedure for the determination of zinc in edible oil samples.

  15. High sensitivity probe absorption technique for time-of-flight measurements on cold atoms

    Indian Academy of Sciences (India)

    A K Mohapatra; C S Unnikrishnan

    2006-06-01

    We report on a phase-sensitive probe absorption technique with high sensitivity, capable of detecting a few hundred ultra-cold atoms in flight in an observation time of a few milliseconds. The large signal-to-noise ratio achieved is sufficient for reliable measurements on low intensity beams of cold atoms. We demonstrate the high sensitivity and figure of merit of the simple method by measuring the time-of-flight of atoms moving upwards from a magneto-optical trap released in the gravitational field.

  16. A new heating strategy in electrothermal atomic absorption spectrometry for better absorbance-time curves at high atomization rate

    Energy Technology Data Exchange (ETDEWEB)

    Torsi, Giancarlo [Department of Chemistry G. Ciamician, University of Bologna, Via F. Selmi 2, 40126 Bologna (Italy)]. E-mail: giancarlo.torsi@unibo.it; Zattoni, Andrea [Department of Chemistry G. Ciamician, University of Bologna, Via F. Selmi 2, 40126 Bologna (Italy); Locatelli, Clinio [Department of Chemistry G. Ciamician, University of Bologna, Via F. Selmi 2, 40126 Bologna (Italy); Valcher, Sergio [Department of Chemistry G. Ciamician, University of Bologna, Via F. Selmi 2, 40126 Bologna (Italy)

    2005-03-31

    The results previously obtained by using fast heating in electrothermal atomic absorption spectrometry are considerably improved by using a new heating sequence which can be summarized as transverse-longitudinal heating mode. The absorbance vs. time curves, obtained with the new heating mode, follow almost perfectly a simple model in which only diffusion is considered as the force acting on the atomic vapor. From the fitting of the experimental absorbance vs. time data points with theoretical values, it is possible to calculate both the absorbance, when all atoms injected are assumed to be present, and their diffusion coefficient. Both values can be calculated by a simple software approach without the operator intervention. The asymptotic absorbance calculated in this way is the maximum absorbance physically obtainable and is the basis for standardless analysis.

  17. Point defect absorption by grain boundaries in α -iron by atomic density function modeling

    Science.gov (United States)

    Kapikranian, O.; Zapolsky, H.; Patte, R.; Pareige, C.; Radiguet, B.; Pareige, P.

    2015-12-01

    Using the atomic density function theory (ADFT), we examine the point defect absorption at [110] symmetrical tilt grain boundaries in body-centered cubic iron. It is found that the sink strength strongly depends on misorientation angle. We also show that the ADFT is able to reproduce reasonably well the elastic properties and the point defect formation volume in α -iron.

  18. DETERMINING BERYLLIUM IN DRINKING WATER BY GRAPHITE FURNACE ATOMIC ABSORPTION SPECTROSCOPY

    Science.gov (United States)

    A direct graphite furnace atomic absorption spectroscopy method for the analysis of beryllium in drinking water has been derived from a method for determining beryllium in urine. Ammonium phosphomolybdate and ascorbic acid were employed as matrix modifiers. The matrix modifiers s...

  19. Circuit Board Analysis for Lead by Atomic Absorption Spectroscopy in a Course for Nonscience Majors

    Science.gov (United States)

    Weidenhammer, Jeffrey D.

    2007-01-01

    A circuit board analysis of the atomic absorption spectroscopy, which is used to measure lead content in a course for nonscience majors, is being presented. The experiment can also be used to explain the potential environmental hazards of unsafe disposal of various used electronic equipments.

  20. Direct microcomputer controlled determination of zinc in human serum by flow injection atomic absorption spectrometry

    DEFF Research Database (Denmark)

    Simonsen, Kirsten Wiese; Nielsen, Bent; Jensen, Arne;

    1986-01-01

    A procedure is described for the direct determination of zinc in human serum by fully automated, microcomputer controlled flow injection atomic absorption spectrometry (Fl-AAS). The Fl system is pumpless, using the negative pressure created by the nebuliser. It only consists of a three-way valve...

  1. Chemical modifiers in electrothermal atomic absorption determination of Platinum and Palladium containing preparations in blood serum

    Directory of Open Access Journals (Sweden)

    Аntonina Alemasova

    2012-11-01

    Full Text Available The biological liquids matrixes influence on the characteristic masses and repeatability of Pt and Pd electrothermal atomic absorption spectroscopy (ETAAS determination was studied. The chemical modifiers dimethylglyoxime and ascorbic acid for matrix interferences elimination and ETAAS results repeatability improvement were proposed while bioliquids ETAAS analysis, and their action mechanism was discussed.

  2. The Use of an Air-Natural Gas Flame in Atomic Absorption.

    Science.gov (United States)

    Melucci, Robert C.

    1983-01-01

    Points out that excellent results are obtained using an air-natural gas flame in atomic absorption experiments rather than using an air-acetylene flame. Good results are obtained for alkali metals, copper, cadmium, and zinc but not for the alkaline earths since they form refractory oxides. (Author/JN)

  3. X-ray absorption studies of atomic environments in semiconductor nanostructures

    CERN Document Server

    Boscherini, F

    2003-01-01

    The use of X-ray absorption fine structure spectroscopy in the investigation of the atomic environment in semiconductor nanostructures is illustrated. After a description of the experimental apparatus two specific examples are reported: the detection of Si-Ge intermixing in Ge quantum dots and the relation between long range elasticity and local distortions in strained InGaAs epilayers.

  4. Optical pumping effect in absorption imaging of F =1 atomic gases

    Science.gov (United States)

    Kim, Sooshin; Seo, Sang Won; Noh, Heung-Ryoul; Shin, Y.

    2016-08-01

    We report our study of the optical pumping effect in absorption imaging of 23Na atoms in the F =1 hyperfine spin states. Solving a set of rate equations for the spin populations in the presence of a probe beam, we obtain an analytic expression for the optical signal of the F =1 absorption imaging. Furthermore, we verify the result by measuring the absorption spectra of 23Na Bose-Einstein condensates prepared in various spin states with different probe-beam pulse durations. The analytic result can be used in the quantitative analysis of F =1 spinor condensate imaging and readily applied to other alkali-metal atoms with I =3 /2 nuclear spin such as 87Rb.

  5. Photon absorption and emission statistics of a two-level atom in a cavity

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chang J. [Sun Moon University, Asan (Korea, Republic of)

    2012-03-15

    The absorption and the emission of photons by an atom involves quantum jumps between states. We investigate the quantum jump statistics for the system of a two-level atom and a single-mode cavity field. We use the Jaynes-Cummings model for this problem, perform Monte Carlo numerical simulations, and give a detailed exact analysis on these simulations. These studies reveal that the waiting-time distribution (WTD) for photon absorptions (emissions) has a unique novel statistic, and that the photon absorption (emission) rate is not uniform, but counter-intuitively depends on the position in the Rabi cycle. The effects of the nonclassical nature of the field on the WTD is discussed.

  6. Determination of nickel in blood and serum samples of oropharyngeal cancer patients consumed smokeless tobacco products by cloud point extraction coupled with flame atomic absorption spectrometry.

    Science.gov (United States)

    Arain, Sadaf Sadia; Kazi, Tasneem Gul; Arain, Jamshed Bashir; Afridi, Hassan Imran; Kazi, Atif Gul; Nasreen, Syeda; Brahman, Kapil Dev

    2014-10-01

    Oropharyngeal cancer is a significant public health issue in the world. The incidence of oropharyngeal cancer has been increased among people who have habit of chewing smokeless tobacco (SLT) in Pakistan. The aim of present study was to evaluate the concentration of nickel (Ni) in biological samples (whole blood, serum) of oral (n = 95) and pharyngeal (n = 84) male cancer patients. For comparison purposes, the biological samples of healthy age-matched referents (n = 150), who consumed and did not consumed SLT products, were also analyzed for Ni levels. As the Ni level is very low in biological samples, a preconcentration procedure has been developed, prior to analysis of analyte by flame atomic absorption spectrometry (FAAS). The Ni in acid-digested biological samples was complexed with ammonium pyrrolidinedithio carbamate (APDC), and a resulted complex was extracted in a surfactant Triton X-114. Acidic ethanol was added to the surfactant-rich phase prior to its analysis by FAAS. The chemical variables, such as pH, amounts of reagents (APDC, Triton X-114), temperature, incubation time, and sample volume were optimized. The resulted data indicated that concentration of Ni was higher in blood and serum samples of cancer patients as compared to that of referents who have or have not consumed different SLT products (p = 0.012-0.001). It was also observed that healthy referents who consumed SLT products have two to threefold higher levels of Ni in both biological samples as compared to those who were not chewing SLT products (p < 0.01).

  7. A novel solidified floating organic drop microextraction method for preconcentration and determination of copper ions by flow injection flame atomic absorption spectrometry.

    Science.gov (United States)

    Sahin, Ciğdem Arpa; Tokgöz, Ilknur

    2010-05-14

    A rapid, simple and cost effective solidified floating organic drop microextraction (SFODME) and flow injection flame atomic absorption spectrometric determination (FI-FAAS) method for copper was developed. In this method, a free microdrop of 1-undecanol containing 1,5-diphenyl carbazide (DPC) as the complexing agent was transferred to the surface of an aqueous sample including Cu(II) ions, while being agitated by a stirring bar in the bulk of the solution. Under the proper stirring conditions, the suspended microdrop can remain at the top-center position of the aqueous sample. After the completion of the extraction, the sample vial was cooled by placing it in a refrigerator for 10min. The solidified microdrop was then transferred into a conical vial, where it melted immediately and diluted to 300microL with ethanol. Finally, copper ions in 200microL of diluted solution were determined by FI-FAAS. Several factors affecting the microextraction efficiency, such as type of extraction solvent, pH, complexing agent concentration, extraction time, stirring rate, sample volume and temperature were investigated and optimized. Under optimized conditions for 100mL of solution, the preconcentration factor was 333 and the enrichment factor was 324. The limit of detection (3s) was 0.4ngmL(-1), the limit of quantification (10s) was 1.1ngmL(-1) and the relative standard deviation (RSD) for 10 replicate measurements of 10ngmL(-1) copper was 0.9%. The proposed method was successfully applied to the determination of copper in different water samples.

  8. On-line sequential injection dispersive liquid-liquid microextraction system for flame atomic absorption spectrometric determination of copper and lead in water samples.

    Science.gov (United States)

    Anthemidis, Aristidis N; Ioannou, Kallirroy-Ioanna G

    2009-06-30

    A simple, sensitive and powerful on-line sequential injection (SI) dispersive liquid-liquid microextraction (DLLME) system was developed as an alternative approach for on-line metal preconcentration and separation, using extraction solvent at microlitre volume. The potentials of this novel schema, coupled to flame atomic absorption spectrometry (FAAS), were demonstrated for trace copper and lead determination in water samples. The stream of methanol (disperser solvent) containing 2.0% (v/v) xylene (extraction solvent) and 0.3% (m/v) ammonium diethyldithiophosphate (chelating agent) was merged on-line with the stream of sample (aqueous phase), resulting a cloudy mixture, which was consisted of fine droplets of the extraction solvent dispersed entirely into the aqueous phase. By this continuous process, metal chelating complexes were formed and extracted into the fine droplets of the extraction solvent. The hydrophobic droplets of organic phase were retained into a microcolumn packed with PTFE-turnings. A portion of 300 microL isobutylmethylketone was used for quantitative elution of the analytes, which transported directly to the nebulizer of FAAS. All the critical parameters of the system such as type of extraction solvent, flow-rate of disperser and sample, extraction time as well as the chemical parameters were studied. Under the optimum conditions the enhancement factor for copper and lead was 560 and 265, respectively. For copper, the detection limit and the precision (R.S.D.) were 0.04 microg L(-1) and 2.1% at 2.0 microg L(-1) Cu(II), respectively, while for lead were 0.54 microg L(-1) and 1.9% at 30.0 microg L(-1) Pb(II), respectively. The developed method was evaluated by analyzing certified reference material and applied successfully to the analysis of environmental water samples.

  9. Room temperature ionic liquids enhanced the speciation of Cr(VI) and Cr(III) by hollow fiber liquid phase microextraction combined with flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Chujie, E-mail: cjzeng@126.com [Department of Chemistry and Material, Yulin Normal College, Yulin, Guangxi 537000 (China); Lin, Yao; Zhou, Neng; Zheng, Jiaoting; Zhang, Wei [Department of Chemistry and Material, Yulin Normal College, Yulin, Guangxi 537000 (China)

    2012-10-30

    Highlights: Black-Right-Pointing-Pointer First reported enhancement effect of RTILs in HF-LPME for the speciation of chromium. Black-Right-Pointing-Pointer The addition of RTILs led to 3.5 times improvement of the sensitivity of Cr(VI). Black-Right-Pointing-Pointer The proposed method is a simplicity, sensitivity, low cost, green method. - Abstract: A new method for the speciation of Cr(VI) and Cr(III) based on enhancement effect of room temperature ionic liquids (RTILs) for hollow fiber liquid phase microextraction (HF-LPME) combined with flame atomic absorption spectrometry (FAAS) was developed. Room temperature ionic liquids (RTILs) and diethyldithiocarbamate (DDTC) were used enhancement reagents and chelating reagent, respectively. The addition of room temperature ionic liquids led to 3.5 times improvement in the determination of Cr(VI). In this method, Cr(VI) reacts with DDTC yielding a hydrophobic complex, which is subsequently extracted into the lumen of hollow fiber, whereas Cr(III) is remained in aqueous solutions. The extraction organic phase was injected into FAAS for the determination of Cr(VI). Total Cr concentration was determined after oxidizing Cr(III) to Cr(VI) in the presence of KMnO{sub 4} and using the extraction procedure mentioned above. Cr(III) was calculated by subtracting of Cr(VI) from the total Cr. Under optimized conditions, a detection limit of 0.7 ng mL{sup -1} and an enrichment factor of 175 were achieved. The relative standard deviation (RSD) was 4.9% for Cr(VI) (40 ng mL{sup -1}, n = 5). The proposed method was successfully applied to the speciation of chromium in natural water samples with satisfactory results.

  10. Atomization mechanisms and gas phase reactions in graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Frech, W.; Lindberg, A.O.; Lundberg, E.; Cedergren, A.

    1986-04-01

    The amounts of carbon monoxide as well as the total amounts of hydrocarbons generated in different types of graphite tubes were investigated under various experimental conditions. Depending on whether or not a matrix like 50 ..mu..g of sodium nitrate was added the amount of carbon monoxide formed during atomization at 1,700 K in a pyrocoated tube was in the range 60 to 600 nmoles when using a thermal pretreatment temperature of 1,200 K. The corresponding values for an uncoated tube were 250 to 1,300 nmoles. The effect of carbon monoxide on the atomization behaviour of silver, bismuth, chromium, copper and lead was investigated experimentally and the results were evaluated by means of thermodynamically based models. In accordance with theoretical predications, only lead, bismuth and chromium, which are assumed to be atomized by oxide decomposition, showed substantial shifts in their appearance temperatures in different gas mixtures, and changes in activation energies.

  11. Determination of cadmium and lead in urine by derivative flame atomic absorption spectrometry using the atom trapping technique

    Science.gov (United States)

    Han-wen, Sun; De-qiang, Zhang; Li-li, Yang; Jian-min, Sun

    1997-06-01

    A method is described for the determinations of cadmium and lead in urine by derivative flame atomic absorption spectrometry with a modified water-cooled stainless steel atom trapping tube. The effects of the trap position, the flame conditions, the coolant flow rates, and the collection time were studied. With a 1 min collection time, the characteristic concentrations (derivative absorbance of 0.0044) for cadmium and lead were 0.028 and 1.4 μg L -1, the detection limits (3σ) were 0.02 and 0.27 μg L -1, respectively. The detection limits and sensitivities of the proposed method were 2 and 3 orders of magnitude higher for 1-3 min collection time than those of conventional flame atomic absorption spectrometry for cadmium and lead, respectively. Urine samples from a small population of normal individuals have been analyzed for cadmium and lead by the proposed method. Satisfactory recoveries of 91-110% and 91-106%, for Cd and Pb were obtained with these urine samples.

  12. Tunable Diode Laser Atomic Absorption Spectroscopy for Detection of Potassium under Optically Thick Conditions.

    Science.gov (United States)

    Qu, Zhechao; Steinvall, Erik; Ghorbani, Ramin; Schmidt, Florian M

    2016-04-05

    Potassium (K) is an important element related to ash and fine-particle formation in biomass combustion processes. In situ measurements of gaseous atomic potassium, K(g), using robust optical absorption techniques can provide valuable insight into the K chemistry. However, for typical parts per billion K(g) concentrations in biomass flames and reactor gases, the product of atomic line strength and absorption path length can give rise to such high absorbance that the sample becomes opaque around the transition line center. We present a tunable diode laser atomic absorption spectroscopy (TDLAAS) methodology that enables accurate, calibration-free species quantification even under optically thick conditions, given that Beer-Lambert's law is valid. Analyte concentration and collisional line shape broadening are simultaneously determined by a least-squares fit of simulated to measured absorption profiles. Method validation measurements of K(g) concentrations in saturated potassium hydroxide vapor in the temperature range 950-1200 K showed excellent agreement with equilibrium calculations, and a dynamic range from 40 pptv cm to 40 ppmv cm. The applicability of the compact TDLAAS sensor is demonstrated by real-time detection of K(g) concentrations close to biomass pellets during atmospheric combustion in a laboratory reactor.

  13. Flame atomic absorption spectrometric (FAAS) determination of copper, iron and zinc in food samples after solid-phase extraction on Schiff base-modified duolite XAD 761

    Energy Technology Data Exchange (ETDEWEB)

    Ghaedi, M., E-mail: m_ghaedi@mail.yu.ac.ir [Chemistry Department, Yasouj University, Yasouj 75918-74831 (Iran, Islamic Republic of); Mortazavi, K. [Chemistry Department, Gachsaran Branch, Islamic Azad University, Gachsaran (Iran, Islamic Republic of); Montazerozohori, M. [Chemistry Department, Yasouj University, Yasouj 75918-74831 (Iran, Islamic Republic of); Shokrollahi, A. [Chemistry Department, Gachsaran Branch, Islamic Azad University, Gachsaran (Iran, Islamic Republic of); Soylak, M. [Chemistry Department, University of Erciyes, 38039 Kayseri (Turkey)

    2013-05-01

    The present study involves the development of solid-phase extraction (SPE) procedure for the preconcentration of trace amounts of copper (Cu{sup 2+}), iron (Fe{sup 3+}) and zinc (Zn{sup 2+}) ions on duolite XAD 761 modified by bis(2-hydroxyacetophenone)-2,2-dimethyl-1,3-propanediimine(BHAPDMPDI). The complexation between the metal ions and the proposed ligand was investigated potentiometrically. The metal ions retained on the sorbent were quantitatively determined via complexation with BHAPDMPDI. The complexed metal ions were efficiently eluted using 6 mL of 4 mol L{sup −1} nitric acid in acetone. The influences of the analytical parameters, including pH, amounts of the ligand and the solid phase, eluent conditions and sample volume, on the recoveries of the metal ions were optimized. Using the optimized parameters, the linear response of the SPE method for Cu{sup 2+}, Zn{sup 2+} and Fe{sup 3+} ions were in the ranges of 0.01–0.34, 0.01–0.28 and 0.02–0.31 μg mL{sup −1}, respectively, and the detection limits for Cu{sup 2+}, Zn{sup 2+} and Fe{sup 3+} ions were 1.8, 1.6 and 2.4 μg mL{sup −1}, respectively. The proposed method exhibits a preconcentration factor of 208 for all of the ions studied and an enhancement factor for Cu{sup 2+}, Fe{sup 3+} and Zn{sup 2+} ions of 34, 28 and 38, respectively. The presented results demonstrate the successful application of the proposed method for the determination of these metal ions in some real samples with high recoveries (> 95%) and reasonable relative standard deviation (RDS < 5%). Highlights: ► Highly efficient adsorbent for dye removal was synthesized. ► The sorbent was fully characterized. ► The proposed method has a potential of a waste water treatment alternative. ► Excellent properties of the sorbent have been illustrated in detail.

  14. Flame atomic absorption spectrometric (FAAS) determination of copper, iron and zinc in food samples after solid-phase extraction on Schiff base-modified duolite XAD 761.

    Science.gov (United States)

    Ghaedi, M; Mortazavi, K; Montazerozohori, M; Shokrollahi, A; Soylak, M

    2013-05-01

    The present study involves the development of solid-phase extraction (SPE) procedure for the preconcentration of trace amounts of copper (Cu(2+)), iron (Fe(3+)) and zinc (Zn(2+)) ions on duolite XAD 761 modified by bis(2-hydroxyacetophenone)-2,2-dimethyl-1,3-propanediimine(BHAPDMPDI). The complexation between the metal ions and the proposed ligand was investigated potentiometrically. The metal ions retained on the sorbent were quantitatively determined via complexation with BHAPDMPDI. The complexed metal ions were efficiently eluted using 6 mL of 4 mol L(-1) nitric acid in acetone. The influences of the analytical parameters, including pH, amounts of the ligand and the solid phase, eluent conditions and sample volume, on the recoveries of the metal ions were optimized. Using the optimized parameters, the linear response of the SPE method for Cu(2+), Zn(2+) and Fe(3+) ions were in the ranges of 0.01-0.34, 0.01-0.28 and 0.02-0.31 μg mL(-1), respectively, and the detection limits for Cu(2+), Zn(2+) and Fe(3+) ions were 1.8, 1.6 and 2.4 μg mL(-1), respectively. The proposed method exhibits a preconcentration factor of 208 for all of the ions studied and an enhancement factor for Cu(2+), Fe(3+) and Zn(2+) ions of 34, 28 and 38, respectively. The presented results demonstrate the successful application of the proposed method for the determination of these metal ions in some real samples with high recoveries (> 95%) and reasonable relative standard deviation (RDS <5%).

  15. Hydride generation – in-atomizer collection of Pb in a quartz trap-and-atomizer device for atomic absorption spectrometry – an interference study

    Energy Technology Data Exchange (ETDEWEB)

    Novotný, Pavel [Institute of Analytical Chemistry of the ASCR, v.v.i., Veveří 97, 602 00 Brno (Czech Republic); High School in Hořice, Husova 1414, 508 01 Hořice (Czech Republic); Kratzer, Jan, E-mail: jkratzer@biomed.cas.cz [Institute of Analytical Chemistry of the ASCR, v.v.i., Veveří 97, 602 00 Brno (Czech Republic)

    2013-01-01

    Interferences of selected hydride forming elements (As, Sb, Bi, Se and Sn) on lead determination by hydride generation atomic absorption spectrometry were extensively studied in both on-line atomization and preconcentration (collection) modes. The commonly used on-line atomization mode was found free of significant interferences, whereas strong interference from Bi was observed when employing the preconcentration mode with plumbane collection in a quartz trap-and-atomizer device. Interference of Bi seems to take place in the preconcentration step. Interference of Bi in the collection mode cannot be reduced by increased hydrogen radical amount in the trap and/or the atomizer. - Highlights: ► Interference study on Pb determination by in-atomizer trapping was performed for the first time. ► Bi was found as a severe interferent in the preconcentration mode (Pb:Bi ratio 1:100). ► No interference was found in the on-line atomization (no preconcentration). ► Bi interference occurs during preconcentration.

  16. Self-corrected sensors based on atomic absorption spectroscopy for atom flux measurements in molecular beam epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Du, Y., E-mail: yingge.du@pnnl.gov, E-mail: scott.chambers@pnnl.gov; Liyu, A. V. [Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99352 (United States); Droubay, T. C.; Chambers, S. A., E-mail: yingge.du@pnnl.gov, E-mail: scott.chambers@pnnl.gov [Fundamental and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352 (United States); Li, G. [Energy and Environment Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352 (United States)

    2014-04-21

    A high sensitivity atom flux sensor based on atomic absorption spectroscopy has been designed and implemented to control electron beam evaporators and effusion cells in a molecular beam epitaxy system. Using a high-resolution spectrometer and a two-dimensional charge coupled device detector in a double-beam configuration, we employ either a non-resonant line or a resonant line with low cross section from the same hollow cathode lamp as the reference for nearly perfect background correction and baseline drift removal. This setup also significantly shortens the warm-up time needed compared to other sensor technologies and drastically reduces the noise coming from the surrounding environment. In addition, the high-resolution spectrometer allows the most sensitive resonant line to be isolated and used to provide excellent signal-to-noise ratio.

  17. Self-corrected Sensors Based On Atomic Absorption Spectroscopy For Atom Flux Measurements In Molecular Beam Epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Du, Yingge; Droubay, Timothy C.; Liyu, Andrey V.; Li, Guosheng; Chambers, Scott A.

    2014-04-24

    A high sensitivity atom flux sensor based on atomic absorption spectroscopy has been designed and implemented to control electron beam evaporators and effusion cells in a molecular beam epitaxy system. Using a high-resolution spectrometer and a two-dimensional charge coupled device (CCD) detector in a double-beam configuration, we employ a non-resonant line or a resonant line with lower absorbance from the same hollow cathode lamp as the reference for nearly perfect background correction and baseline drift removal. This setup also significantly shortens the warm-up time needed compared to other sensor technologies and drastically reduces the noise coming from the surrounding environment. In addition, the high-resolution spectrometer allows the most sensitive resonant line to be isolated and used to provide excellent signal-to-noise ratio.

  18. Self-corrected sensors based on atomic absorption spectroscopy for atom flux measurements in molecular beam epitaxy

    Science.gov (United States)

    Du, Y.; Droubay, T. C.; Liyu, A. V.; Li, G.; Chambers, S. A.

    2014-04-01

    A high sensitivity atom flux sensor based on atomic absorption spectroscopy has been designed and implemented to control electron beam evaporators and effusion cells in a molecular beam epitaxy system. Using a high-resolution spectrometer and a two-dimensional charge coupled device detector in a double-beam configuration, we employ either a non-resonant line or a resonant line with low cross section from the same hollow cathode lamp as the reference for nearly perfect background correction and baseline drift removal. This setup also significantly shortens the warm-up time needed compared to other sensor technologies and drastically reduces the noise coming from the surrounding environment. In addition, the high-resolution spectrometer allows the most sensitive resonant line to be isolated and used to provide excellent signal-to-noise ratio.

  19. Electrothermal atomization atomic absorption spectrometry for the determination of lead in urine: results of an interlaboratory study

    Science.gov (United States)

    Parsons, Patrick J.; Slavin, Walter

    1999-05-01

    Results of an interlaboratory study are reported for the determination of lead in urine. Two levels of a lyophilized material containing biologically-bound lead were prepared using pooled urine obtained from lead-poisoned children undergoing the CaNa 2EDTA mobilization test. The materials were circulated to a group of reference laboratories that participate in the `New York State Proficiency Testing Program for Blood Lead'. Results of the initial round-robin gave all-method consensus target values of 145±22 μg/l (S.D.) for lot 17 and 449±43 μg/l (S.D.) for lot 20. The interlaboratory exercise was repeated some 5 years later and consensus target values were re-calculated using the grand mean (excluding outliers) of results reported by laboratories using electrothermal atomization atomic absorption spectrometry (ETAAS). The re-calculated target values were 139±10 μg/l (S.D.) and 433±12 μg/l (S.D.). The urine reference materials were also analyzed for lead by several laboratories using other instrumental techniques including isotope dilution (ID), inductively coupled plasma (ICP) mass spectrometry (MS), flame atomic absorption with extraction, ICP-atomic emission spectrometry, ID-gas chromatography MS and flow injection-hydride generation AAS, thus providing a rich source of analytical data with which to characterize them. The materials were also used in a long-term validation study of an ETAAS method developed originally for blood lead determinations that has since been used unmodified for the determination of lead in urine also. Recently, urine lead method performance has been tracked in a proficiency testing program specifically for this analysis. In addition, a number of commercial control materials have been analyzed and evaluated.

  20. A double cell for X-ray absorption spectrometry of atomic Zn

    CERN Document Server

    Mihelic, A; Arcon, I; Padeznik-Gomilsek, J; Borowski, M

    2002-01-01

    A high-temperature cell with a double wall design has been constructed for X-ray absorption spectrometry of metal vapors. The inner cell, assembled from a corundum tube and thin plates without welding or reshaping, serves as a container of the vapor sample. It is not vacuum tight: instead, the outer tube provides inert atmosphere. Several spectra of K-edge atomic absorption of Zn were obtained in the stationary working regime below the Zn boiling point. The K-edge profile shows an extremely strong resonance and, above the continuum threshold, coexcitations of the outer electrons.

  1. Determination of zinc in serum, blood, and ultrafiltrate fluid from patients on hemofiltration by graphite furnace/atomic absorption spectroscopy or flow injection analysis/atomic absorption spectroscopy.

    Science.gov (United States)

    de Blas, O J; Rodriguez, R S; Mendez, J H; Tomero, J A; Gomez, B de L; Gonzalez, S V

    1994-01-01

    Two methods were optimized for the determination of zinc in samples of blood, serum, and ultrafiltrate fluid from patients with chronic renal impairment undergoing hemofiltration. In the first procedure, after acid digestion of the samples, Zn in blood and serum is determined by a system coupled to flow injection analysis and atomic absorption spectroscopy. The method is rapid, automated, simple, needs small amounts of sample, and has acceptable analytical characteristics. The analytical characteristics obtained were as follows: determination range of method, 0.05-2.0 ppm of Zn; precision as coefficient of variation (CV), 5.3%; recovery, 95-105%; and detection limit (DL), 0.02 ppm. The second method is optimized for ultrafiltrate fluid because the sensitivity of the first procedure is not suitable for the levels of Zn (ppb or ng/mL) in these samples. The technique chosen was atomic absorption spectroscopy with electrothermal atomization in a graphite furnace. The analytical characteristics obtained were as follows: determination range of method, 0.3-2.0 ppb Zn; CV, 5.7%; recovery, 93-107%; and DL, 0.12 ppb. The methods were used to determine zinc in samples of blood, serum, and ultrafiltrate fluid from 5 patients with chronic renal impairment undergoing hemofiltration to discover whether there were significant differences in the zinc contents of blood, serum, and ultrafiltrate fluid after the hemofiltration process. An analysis of variance of the experimental data obtained from a randomly selected group of 5 patients showed that zinc concentrations in the ultrafiltrate fluid, venous blood, and venous serum do not vary during hemofiltration (p < 0.05), whereas in arterial blood and serum, the time factor has a significant effect.

  2. Unraveling the absorption spectra of alkali metal atoms attached to helium nanodroplets.

    Science.gov (United States)

    Bünermann, Oliver; Droppelmann, Georg; Hernando, Alberto; Mayol, Ricardo; Stienkemeier, Frank

    2007-12-13

    The absorption spectra of the first electronic exited state of alkali metal atoms on helium nanodroplets formed of both 4He and 3He isotopes were studied experimentally as well as theoretically. In the experimental part new data on the 2palkali metal atoms with helium nanodroplets, a model calculation was performed. New helium density profiles as well as a refined model allowed us to achieve good agreement with the experimental findings. For the first time the red-shifted intensities in the lithium and sodium spectra are explained in terms of enhanced binding configurations in the excited state displaced spatially from the ground state configurations.

  3. Absorption-Dispersion Properties in a Four-Level Atomic System with Vacuum-Induced Coherence

    Institute of Scientific and Technical Information of China (English)

    WEI Hua; LI Jia-Hua; ZHAN Zhi-Ming; PENG Ju-Cun

    2005-01-01

    We discuss and analyze absorption-dispersion response for the probe field in a typical four-level atomic system with vacuum-induced coherence (VIC) arising from the cross coupling pathways associated with a pair of upper excited hyperfine levels. We find that VIC effect can preserve electromagnetically induced transparency (EIT) by using the detailed numerical simulations based on the density-matrix equations and analytical calculations in the dressed-state picture. We also show that the atomic hyperfine structure cannot be a hindrance to obtaining EIT.

  4. Absorption-Dispersion Properties in a Four-Level Atomic System with Vacuum-Induced Coherence

    Institute of Scientific and Technical Information of China (English)

    WEIHua; LIJia-Hua; ZHANZhi-Ming; PENGJu-Cun

    2005-01-01

    We discuss and analyze absorption-dispersion response for the probe field in a typical four-level atomic system with vacuum-induced coherence (VIC) arising from the cross coupling pathways associated with a pair of upper excited hyperfine levels. We find that VIC effect can preserve electromagnetically induced transparency (FIT) by using the detailed numerical simulations based on the density-matrix equations and analytical calculations in the dressed-state picture. We also show that the atomic hyperfine structure cannot be a hindrance to obtaining EIT.

  5. Determination of copper, zinc and iron in broncho-alveolar lavages by atomic absorption spectroscopy.

    Science.gov (United States)

    Harlyk, C; Mccourt, J; Bordin, G; Rodriguez, A R; van der Eeckhout, A

    1997-11-01

    Concentrations of Zn, Cu and Fe were measured in 157 broncho-alveolar lavages (BAL), before and after centrifugation, collected at the Leuven University Hospital (Belgium). Zn was measured by flame-atomic absorption spectroscopy, using direct calibration, while Cu and Fe were determined by electrothermal atomic absorption spectroscopy, using the method of standard additions. For Fe only 56 samples were measured. Most of the studied elements are present in the liquid phase (supernatant). About 90% of Cu concentrations lie between 0 and 15 micrograms/kg, while 90% of Zn concentrations are lower than 230 micrograms/kg, with 30% between 30 and 70 micrograms/kg, and 50% between 100 and 200 micrograms/kg. There seems to be a reverse relationship between Cu and Zn levels with high Cu going along with low Zn and vice versa.

  6. Absorptive reduction and width narrowing in A-type atoms confined between two dielectric walls

    Institute of Scientific and Technical Information of China (English)

    Li Yuan-Yuan; Hou Xun; Bai Jin-Tao; Yan Jun-Feng; Gan Chen-Li; Zhang Yan-Peng

    2008-01-01

    This paper investigates the absorptive reduction and the width narrowing of electromagnetically induced trans- parency (EIT) in a thin vapour film of A-type atoms confined between two dielectric walls whose thickness is comparable with the wavelength of the probe field. The absorptive lines of the weak probe field exhibit strong reductions and very narrow EIT dips, which mainly results from the velocity slow-down effects and transient behaviour of atoms in a con-fined system. It is also shown that the lines are modified by the strength of the coupling field and the ratio of L/λ, with L the film thickness and A the wavelength of the probe field. A simple robust recipe for EIT in a thin medium is achievable in experiment.

  7. Cadmium, copper, lead, and zinc determination in precipitation: A comparison of inductively coupled plasma atomic emission spectrometry and graphite furnace atomization atomic absorption spectrometry

    Science.gov (United States)

    Reddy, M.M.; Benefiel, M.A.; Claassen, H.C.

    1987-01-01

    Selected trace element analysis for cadmium, copper, lead, and zinc in precipitation samples by inductively coupled plasma atomic emission Spectrometry (ICP) and by atomic absorption spectrometry with graphite furnace atomization (AAGF) have been evaluated. This task was conducted in conjunction with a longterm study of precipitation chemistry at high altitude sites located in remote areas of the southwestern United States. Coefficients of variation and recovery values were determined for a standard reference water sample for all metals examined for both techniques. At concentration levels less than 10 micrograms per liter AAGF analyses exhibited better precision and accuracy than ICP. Both methods appear to offer the potential for cost-effective analysis of trace metal ions in precipitation. ?? 1987 Springer-Verlag.

  8. Literature study of microwave-assisted digestion using electrothermal atomic absorption spectrometry.

    Science.gov (United States)

    Chakraborty, R; Das, A K; Cervera, M L; De La Guardia, M

    1996-05-01

    The literature on the use of microwave-assisted digestion procedures for subsequent sample analysis by means of electrothermal atomic absorption spectrometry (ETAAS) is reviewed. The literature survey reveals that this digestion technique has been applied mainly for biological materials. The elements most extensively determined by this method are cadmium and lead followed by copper, chromium, nickel and iron. The microwave digestion conditions, ETAAS furnace programmes and analytical details of the developed methodologies have been carefully revised.

  9. Determination of Trace Iron in High Purity Sodium Fluoride by Graphite Furnace Atomic Absorption Spectrometry

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A method is described for the direct determination of iron in high purity sodium fluoride using graphite furnace atomic absorption spectrometry. Interferences caused by the matrix are investigated. It is shown that the ashing temperature can be increased to 1 400°C and matrix interferences eliminated, the sensi tivity of iron increased in 1.27 fold by the addition of nickel nitrate. The method is applied to the determina tion of iron in sodium fluoride and satisfactory results are obtained.

  10. Determination of diethyllead in the urine by flameless atomic absorption spectrometry.

    OpenAIRE

    Turlakiewicz, Z; Jakubowski, M.; Chmielnicka, J

    1985-01-01

    A method for the determination of diethyllead in urine by flameless atomic absorption spectrometry after chelation with glyoxal-bis (2-hydroxyanil) and extraction of the formed complex with methyl isobutyl ketone is described. The method is specific in relation to both triethyllead and inorganic lead. The limit of detection was 3.2 micrograms Pb/l and the relative standard deviation in the concentration range 20-100 micrograms Pb/l was 0.076.

  11. Speciation analysis of arsenic in biological matrices by automated hydride generation-cryotrapping-atomic absorption spectrometry with multiple microflame quartz tube atomizer (multiatomizer).

    Science.gov (United States)

    This paper describes an automated system for the oxidation state specific speciation of inorganic and methylated arsenicals by selective hydride generation - cryotrapping- gas chromatography - atomic absorption spectrometry with the multiatomizer. The corresponding arsines are ge...

  12. Radiation trapping in atomic absorption spectroscopy at lead determination in different matricies

    Energy Technology Data Exchange (ETDEWEB)

    El-Gohary, Z. [Department of Physics, Faculty of Science, Menoufia University, Shebin El-Koom (Egypt)]. E-mail: zhelgohary@yahoo.com

    2005-08-15

    The determination of lead by flame atomic absorption analysis in the presence of Sn and Fe atoms and different matrices such as OH and SO{sub 3} was investigated with the objective of understanding the spectral interference processes at the analytical lines 283.31 nm for a wide range of concentration. The radiation trapping factor was interpreted and evaluated assuming Voigt distribution of the atomic and rotational lines in the flame. The radiation trapping factor was increased by increasing the number density (plasma of the absorbing medium is optically thick). In plasma, there is a certain point of equilibrium between the trapping and the escaping of radiation, which is relevant to 50% of absorption. The spectral background interference can cause a variation of the number density at equilibrium point as a result of the degree of overlap with the analytical line. The spectral background interference can be easily avoided by using another resonance absorption line for the analysis. The chemical modification of the matrix is applied to minimize the interference effect. Nitric acid, ammonium nitrate and magnesium nitrate are most commonly recommended as matrix modifiers.

  13. Radiation trapping in atomic absorption spectroscopy at lead determination in different matricies

    Science.gov (United States)

    El-Gohary, Z.

    2005-08-01

    The determination of lead by flame atomic absorption analysis in the presence of Sn and Fe atoms and different matrices such as OH and SO3 was investigated with the objective of understanding the spectral interference processes at the analytical lines 283.31 nm for a wide range of concentration. The radiation trapping factor was interpreted and evaluated assuming Voigt distribution of the atomic and rotational lines in the flame. The radiation trapping factor was increased by increasing the number density (plasma of the absorbing medium is optically thick). In plasma, there is a certain point of equilibrium between the trapping and the escaping of radiation, which is relevant to 50% of absorption. The spectral background interference can cause a variation of the number density at equilibrium point as a result of the degree of overlap with the analytical line. The spectral background interference can be easily avoided by using another resonance absorption line for the analysis. The chemical modification of the matrix is applied to minimize the interference effect. Nitric acid, ammonium nitrate and magnesium nitrate are most commonly recommended as matrix modifiers.

  14. Absorption and dispersion control in a five-level M-type atomic system

    Institute of Scientific and Technical Information of China (English)

    Yang Hong; Yan Dong; Zhang Mei; Fang Bo; Zhang Yan; Wu Jin-Hui

    2012-01-01

    We investigate the steady optical response of a coherently driven five-level M-type atomic system in three different situations.When all three coupling fields have the same zero detuning,we just find one deep transparency window accompanied by a steep normal dispersion in the probe absorption and dispersion spectra.When two coupling fields are detuned from the relevant transitions to the same extent,however,a second deep transparency window may be observed in the presence of a narrow absorption line of linewidth ~ 50 kHz.In this case,two single-photon far-detuned transitions can be replaced by a two-photon resonant transition,so the five-level M system in fact reduces into a four-level quasi-A system.Finally,we note that no deep transparency windows and no narrow absorption lines can be found when all three coupling fields have unequal detunings.

  15. Time-resolved Absorption Spectra of the Laser-dressed Hydrogen Atom

    Science.gov (United States)

    Murakami, Mitsuko; Chu, Shih-I.

    2013-05-01

    A theoretical study of the transient absorption spectra for the laser-dressed hydrogen atom based on the accurate numerical solution of the time-dependent Schrödinger equation is presented. The timing of absorption is controlled by the time delay between an isolated extreme ultraviolet (XUV) pulse and a dressing infrared (IR) field. We identify two different kinds of physical processes in the spectra. One is the formation of dressed states, signified by the appearance of sidebands between the XUV absorption lines separated by one IR-photon energy. We show that their population is maximized when the XUV pulse coincides with the zero-crossing of the IR field, and that their energy can be manipulated by using a chirped IR field. The other process is the dynamical AC Stark shift induced by the IR field and probed by the XUV pulse. Our calculations indicate that the accidental degeneracy of the hydrogen atom leads to the multiple splittings of each XUV absorption line whose separations change in response to a slowly-varying IR envelope. Furthermore, we observe the Autler-Townes doublets for the n=2 and 3 states using the 656 nm dressing field, but their separation does not agree with the prediction by the conventional 3-level model that neglects the dynamical AC Stark effects.

  16. Self-assembly based plasmonic arrays tuned by atomic layer deposition for extreme visible light absorption.

    Science.gov (United States)

    Hägglund, Carl; Zeltzer, Gabriel; Ruiz, Ricardo; Thomann, Isabell; Lee, Han-Bo-Ram; Brongersma, Mark L; Bent, Stacey F

    2013-07-10

    Achieving complete absorption of visible light with a minimal amount of material is highly desirable for many applications, including solar energy conversion to fuel and electricity, where benefits in conversion efficiency and economy can be obtained. On a fundamental level, it is of great interest to explore whether the ultimate limits in light absorption per unit volume can be achieved by capitalizing on the advances in metamaterial science and nanosynthesis. Here, we combine block copolymer lithography and atomic layer deposition to tune the effective optical properties of a plasmonic array at the atomic scale. Critical coupling to the resulting nanocomposite layer is accomplished through guidance by a simple analytical model and measurements by spectroscopic ellipsometry. Thereby, a maximized absorption of light exceeding 99% is accomplished, of which up to about 93% occurs in a volume-equivalent thickness of gold of only 1.6 nm. This corresponds to a record effective absorption coefficient of 1.7 × 10(7) cm(-1) in the visible region, far exceeding those of solid metals, graphene, dye monolayers, and thin film solar cell materials. It is more than a factor of 2 higher than that previously obtained using a critically coupled dye J-aggregate, with a peak width exceeding the latter by 1 order of magnitude. These results thereby substantially push the limits for light harvesting in ultrathin, nanoengineered systems.

  17. Some problems connected with boron determination by atomic absorption spectroscopy and the sensitivity improvement

    Directory of Open Access Journals (Sweden)

    JELENA J. SAVOVIC

    2001-08-01

    Full Text Available Two atomizers were compared: an N2O–C2H2 flame and a stabilized U-shaped DC arc with aerosol supply. Both the high plasma temperature and the reducing atmosphere obtained by acetylene addition to the argon stream substantially increase the sensitivity of boron determination by atomic absorption spectroscopy (AAS when the arc atomizer is used. The results were compared with those for silicon as a control element. The experimental characteristic concentrations for both elements were compared with the computed values. The experimentally obtained characteristic concentration for boron when using the arc atomizer was in better agreement with the calculated value. It was estimated that the influence of stable monoxide formation on the sensitivity for both elements was about the same, but reduction of analyte and formation of non-volatile carbide particles was more important for boron, which is the main reason for the low sensitivity of boron determination using a flame atomizer. The use of an arc atomizer suppresses this interference and significantly improves the sensitivity of the determination.

  18. Determination of trace elements in paints by direct sampling graphite furnace atomic absorption spectrometry.

    Science.gov (United States)

    Bentlin, Fabrina R S; Pozebon, Dirce; Mello, Paola A; Flores, Erico M M

    2007-10-17

    A direct sampling graphite furnace atomic absorption spectrometric (DS-GFAAS) method for the determination of Cd, Pb, Cr, Ni, Co and Cu in paints has been developed. Serigraphy, acrylic and tattoo paints were analysed. Approaches like pyrolysis and atomization temperatures, modifiers and sample mass introduced in the atomizer were studied. Quantification was performed using calibration curves measured with aqueous standard solutions pipetted onto the platform. The sample mass introduced in the graphite tube ranged from 0.02 to 8.0 mg. Palladium was used as modifier for Cd, Pb and Cu, while Mg(NO3)2 was used for Co. For Ni determination, the graphite platform was covered with carbon powder. The characteristic masses of Cd, Pb, Cr, Ni, Co and Cu were 1.4, 22.5, 7.9, 11.0, 9.6 and 12.5 pg, while the limits of detection were 0.0004, 0.001, 0.03, 0.22, 0.11 and 0.05 microg g(-1) of Cd, Pb, Cr, Ni, Co and Cu, respectively. The accuracy was determined by comparison of the results with those obtained by inductively coupled plasma mass spectrometry (ICP-MS) and graphite furnace atomic absorption spectrometry (GFAAS), using liquid sampling of digests. For matrix characterization, major and minor elements (Al, Mg, Ba, Ca, Cr, Cu, Pb, Sr, Ti and Mg) were determined by inductively coupled plasma optical emission spectrometry (ICP OES).

  19. Determination of trace elements in paints by direct sampling graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Bentlin, Fabrina R.S. [Instituto de Quimica, Universidade Federal do Rio Grande do Sul, UFRGS, 91501-970 Porto Alegre, RS (Brazil); Pozebon, Dirce [Instituto de Quimica, Universidade Federal do Rio Grande do Sul, UFRGS, 91501-970 Porto Alegre, RS (Brazil)], E-mail: dircepoz@iq.ufrgs.br; Mello, Paola A.; Flores, Erico M.M. [Departamento de Quimica, Universidade Federal de Santa Maria, UFSM, 97105-900 Santa Maria, RS (Brazil)

    2007-10-17

    A direct sampling graphite furnace atomic absorption spectrometric (DS-GFAAS) method for the determination of Cd, Pb, Cr, Ni, Co and Cu in paints has been developed. Serigraphy, acrylic and tattoo paints were analysed. Approaches like pyrolysis and atomization temperatures, modifiers and sample mass introduced in the atomizer were studied. Quantification was performed using calibration curves measured with aqueous standard solutions pipetted onto the platform. The sample mass introduced in the graphite tube ranged from 0.02 to 8.0 mg. Palladium was used as modifier for Cd, Pb and Cu, while Mg(NO{sub 3}){sub 2} was used for Co. For Ni determination, the graphite platform was covered with carbon powder. The characteristic masses of Cd, Pb, Cr, Ni, Co and Cu were 1.4, 22.5, 7.9, 11.0, 9.6 and 12.5 pg, while the limits of detection were 0.0004, 0.001, 0.03, 0.22, 0.11 and 0.05 {mu}g g{sup -1} of Cd, Pb, Cr, Ni, Co and Cu, respectively. The accuracy was determined by comparison of the results with those obtained by inductively coupled plasma mass spectrometry (ICP-MS) and graphite furnace atomic absorption spectrometry (GFAAS), using liquid sampling of digests. For matrix characterization, major and minor elements (Al, Mg, Ba, Ca, Cr, Cu, Pb, Sr, Ti and Mg) were determined by inductively coupled plasma optical emission spectrometry (ICP OES)

  20. Variations of Positive and Negative Dispersions in Both Highly and Weakly Absorptive Atomic Systems

    Science.gov (United States)

    Abi-Salloum, Tony; Snell, Scott; Davis, Jon; Narducci, Frank

    2011-05-01

    Positive and negative dispersive media are essential in subluminal, superluminal and negative group velocity pulse propagation applications. Three-level atomic media at resonance, especially the Lambda configuration, are positively dispersive and transparent. In contrast, two-level atomic systems are negatively dispersive and opaque. In this work we study higher level atomic systems comprised of three fields coupled to three levels (double lambda) or four levels (N-Scheme). We explore the systems of interest for critical features such as negative dispersion and transparency, a combination that is needed in numerous applications, e.g. optical gyroscopes. We solve the time dependent equations perturbatively and compare them to well established behavior in three-level systems. Some of the results are analyzed in terms of resonances which control the different features of the observed dispersive and absorptive behaviors.

  1. A Green Preconcentration Method for Determination of Cobalt and Lead in Fresh Surface and Waste Water Samples Prior to Flame Atomic Absorption Spectrometry

    Science.gov (United States)

    Naeemullah; Kazi, Tasneem Gul; Shah, Faheem; Afridi, Hassan Imran; Khan, Sumaira; Arian, Sadaf Sadia; Brahman, Kapil Dev

    2012-01-01

    Cloud point extraction (CPE) has been used for the preconcentration and simultaneous determination of cobalt (Co) and lead (Pb) in fresh and wastewater samples. The extraction of analytes from aqueous samples was performed in the presence of 8-hydroxyquinoline (oxine) as a chelating agent and Triton X-114 as a nonionic surfactant. Experiments were conducted to assess the effect of different chemical variables such as pH, amounts of reagents (oxine and Triton X-114), temperature, incubation time, and sample volume. After phase separation, based on the cloud point, the surfactant-rich phase was diluted with acidic ethanol prior to its analysis by the flame atomic absorption spectrometry (FAAS). The enhancement factors 70 and 50 with detection limits of 0.26 μg L−1 and 0.44 μg L−1 were obtained for Co and Pb, respectively. In order to validate the developed method, a certified reference material (SRM 1643e) was analyzed and the determined values obtained were in a good agreement with the certified values. The proposed method was applied successfully to the determination of Co and Pb in a fresh surface and waste water sample. PMID:23227429

  2. Cloud Point Extraction for the Determination of Trace Amounts of Cobalt in Water and Food Samples by Flame Atomic Absorption Spectrometry

    Directory of Open Access Journals (Sweden)

    Shangzhi Wang

    2013-01-01

    Full Text Available A cloud point extraction (CPE procedure which was developed for the separation and preconcentration of trace amounts of cobalt is combined with flame atomic absorption spectrometry (FAAS to determine trace amounts of cobalt in water and food samples. The procedure is based on the formation of the hydrophobic complex between Co(II and 4-methoxy-2-sulfo-benzenediazoaminoazo-benzene (MOSDAA followed by its extraction into a Triton X-114 surfactant-rich phase. The parameters such as pH of sample, concentrations of MOSDAA and Triton X-114, equilibrium temperature, and equilibrium time, which affect both complexation and extraction, are optimized. Under the selected optimum conditions, the preconcentration of 10.0 mL, 0.1 μg mL−1 Co(II solution results in a limit of detection of 0.47 ng mL−1 (3σ and an enrichment factor of 19. A relative standard deviation of 2.78% (,  μg mL−1 for the determination of Co(II is obtained. The proposed method was applied for the determination of trace amounts of cobalt in river water and millet samples with satisfactory results.

  3. Optimization of cloud point extraction procedure with response surface methodology for quantification of iron by means of flame atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    Abdolmohammad-Zadeh Hossein

    2013-01-01

    Full Text Available A simple micelle-mediated phase separation method has been developed for the pre-concentration of trace levels of iron as a prior step to determination by flame atomic absorption spectrometry (FAAS. The method is based on the cloud point extraction (CPE of iron using non-ionic surfactant polyethyleneglycolmono-p-nonylphenylether (PONPE 7.5 without adding any chelating agent. Several variables affecting the extraction efficiency were studied and optimized utilizing central composite design (CCD and three levels full factorial design. Under the optimum conditions, the limit of detection (LOD, limit of quantification (LOQ and pre-concentration factor were 1.5 μg L-1, 5.0 μg L-1 and 100, respectively. The relative standard deviation (RSD for six replicate determinations at 50 μg L−1 Fe(III level was 1.97%. The calibration graph was linear in the rage of 5-100 μg L-1, with a correlation coefficient of 0.9921. The developed method was validated by the analysis of two certified reference materials and applied successfully to the determination of trace amounts of Fe(III in water and rice samples.

  4. [Analysis the properties of Cr2O7(2-) adsorption onto functional organic reagent modified nano-SiO2 by flame atomic absorption spectroscopy].

    Science.gov (United States)

    Zhang, Zu-Lei; Li, Lei

    2011-02-01

    A new type of functional organic reagent modified nano-SiO2 sorbent (Si/ (CH2)3-NH-CO-Ph-CH2-P(C6H5)3 Br) was synthesized by several reasonable organic combination reactions using nano-SiO2, gamma-Aminopropyl triethoxysilane (KH-550) and functional organic reagent (COOH-Ph-CH2-P(C6 H5)3 Br) as raw materials. The prepared new sorbent was characterized by using FTIR, particle diameter and TG. A batch of adsorption experiments was performed to evaluate its adsorption behavior of Cr2O7(2-) by flame atomic absorption spectroscopy (FAAS). The effects of solution pH, shaken time and sorbent amount on the extraction of Cr2O7(2-) from aqueous solutions were studied. Results showed that when under the optimum conditions the solution pH 1, sorbent amount = 0.1 g, and shaken time = 30 min, the adsorption efficiency can be more than 95%. It indicated that this novel sorbent (Si/ (CH2)3-NH-CO-Ph-CH2-P (C6 H5)3 Br) was a solid sorbent being efficient and low-cost, with convenient separation, and can remove trace Cr2 O7(2-) in environmental waste water.

  5. Determination of nickel in food samples by flame atomic absorption spectroscopy after preconcentration and microextraction based ionic liquids using full factorial and central composite design.

    Science.gov (United States)

    Zarei, Zohre; Shemirani, Farzaneh

    2012-12-01

    In this research, a microextraction technique based on ionic liquids (ILs) termed in situ solvent formation microextraction (ISFME) was used for determination of nickel in solutions. 1-(2-pyridylazo)-2-naphtol (PAN) was chosen as a complexing agent. After preconcentration, the settled IL-phase was dissolved in 50 μL of ethanol and aspirated into the flame atomic absorption spectrometer (FAAS) using a home-made microsample introduction system. Injection of 50 μL volumes of analyte into an air-acetylene flame provided very sensitive spike-like and reproducible signals. ISFME is based on phase separation phenomenon of ionic liquids in aqueous solutions. This method is simple and rapid for extraction and preconcentration of metal ions from food samples and can be applied for the sample solutions containing very high concentrations of salt. Furthermore, this technique is much safer in comparison with the organic solvent extraction because of using ionic liquid. The effective parameters such as amount of IL, salt effect, concentration of the chelating agent and ion pairing agent were inspected by a full factorial design to identify important parameters and their interactions. Next, a central composite design was applied to obtain optimum point of the important parameters. Under the optimum conditions, the calibration graph was linear over the range of 2 to 80 ng/mL. The limit of detection and relative standard deviation (n= 6) were 0.6 ng/mL and 2%, respectively.

  6. On-line preconcentration system using a microcolumn packed with Alizarin Red S-modified alumina for zinc determination by flame atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    A.M. Haji Shabani

    2009-01-01

    Full Text Available A simple and sensitive on-line flow injection system for determination of zinc with FAAS has been described. The method is based on the separation and preconcentration of zinc on a microcolumn of immobilized Alizarin Red S on alumina. The adsorbed analyte is then eluted with 250 µL of nitric acid (1 mol L-1 and is transported to flame atomic absorption spectrometer for quantification. The effect of pH, sample and eluent flow rates and presence of various cations and anions on the retention of zinc was investigated. The sorption of zinc was quantitative in the pH range of 5.5-8.5. For a sample volume of 25 mL an enrichment factor of 144 and a detection limit (3S of 0.2 µg L-1 was obtained. The precision (RSD, n=7 was 3.0% at the 20 µg L-1 level. The developed system was successfully applied to the determination of zinc in water samples, hair, urine and saliva.

  7. Preconcentration of Copper Using 1,5-Diphenyl Carbazide as the Complexing Agent via Dispersive Liquid-Liquid Microextraction and Determination by Flame Atomic Absorption Spectrometry

    Directory of Open Access Journals (Sweden)

    Reyhaneh Rahnama

    2013-01-01

    Full Text Available We report a simple and sensitive microextraction system for the preconcentration and determination of Cu (II by flame atomic absorption spectrometry (FAAS. Dispersive liquid-liquid microextraction is a modified solvent extraction method and its acceptor-to-donor phase ratio is greatly reduced compared with other methods. In the proposed approach, 1,5-diphenyl carbazide (DPC was used as a copper ion selective complexing agent. Several variables such as the extraction and dispersive solvent type and volume, pH of sample solution, DPC concentration, extraction time, and ionic strength were studied and optimized for a quantitative preconcentration and determination of copper (II and at the optimized conditions: 60 μL, 0.5 mL, and 5 mL of extraction solvent (chloroform, disperser solvent (ethanol, and sample volume, respectively, a linear calibration graph was obtained over the concentration range of 10–200 μg L−1 for Cu (II with R2 = 0.9966. The limit of detection (3Sb/m, and preconcentration factor are 2 μg L−1 and 25, respectively. The relative standard deviation (n=10 at 100 μg L−1 of Cu (II is 2.5%. The applicability of the developed technique was evaluated by application to spiked environmental water samples.

  8. Preconcentration of trace amounts of lead in water samples with cetyltrimethylammonium bromide coated magnetite nanoparticles and its determination by flame atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    Mohammad Faraji

    2016-11-01

    Full Text Available A sensitive and simple magnetic solid phase extraction procedure was presented for the preconcentration of lead ions in environmental water samples. In the present study, lead ions form complexes with 1-(2-pyridilazo-2-naphthol reagent (PAN in basic medium, and then are quantitatively extracted to the surface of cetyltrimethylammonium bromide (CTAB-coated magnetite nanoparticles (Fe3O4 NPs. After magnetic separation of adsorbent, the adsorbent was eluted with 0.5% (v/v HCl in methanol prior to its analysis by flame atomic absorption spectrometry (FAAS. The pH of sample, concentrations of PAN, amounts of CTAB and Fe3O4 NPs, sample volume and desorption conditions were optimized. Under optimum conditions, the calibration curve was linear in the range of 0.05–100 ng mL−1 with R2 = 0.9996. Detection and quantification limits of the proposed method were 0.005 and 0.05 ng mL−1, respectively. Enhancement factor of 1050 was achieved using this method to extract 1000 mL of different environmental water samples. Compared with conventional solid phase extraction methods, the advantages of this method still include easy preparation of sorbents, short times of sample pre-treatment, high extraction yield, and high breakthrough volume. It shows great analytical potential in preconcentration of lead from large volume water samples.

  9. A novel ionic liquid/micro-volume back extraction procedure combined with flame atomic absorption spectrometry for determination of trace nickel in samples of nutritional interest

    Energy Technology Data Exchange (ETDEWEB)

    Dadfarnia, Shayesteh, E-mail: sdadfarnia@yazduni.ac.ir [Department of Chemistry, Faculty of Science, Yazd University, 89195/74, Yazd (Iran, Islamic Republic of); Haji Shabani, Ali Mohammad; Shirani Bidabadi, Mahboubeh; Jafari, Abbas Ali [Department of Chemistry, Faculty of Science, Yazd University, 89195/74, Yazd (Iran, Islamic Republic of)

    2010-01-15

    A simple, highly sensitive and environment-friendly method for the determination of trace amount of nickel ion in different matrices is proposed. In the preconcentration step, the nickel from 10 mL of an aqueous solution was extracted into 500 {mu}L of ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate [C{sub 4}MIM][PF{sub 6}], containing PAN as complexing agent. Subsequently, the PAN complex was back-extracted into 250 {mu}L of nitric acid solution, and 100 {mu}L of it was analyzed by flow injection flame atomic absorption spectrometry (FI-FAAS). The main parameter influencing the extraction and determination of nickel, such as pH, concentration of PAN, extraction time and temperature, ionic strength, and concentration of stripping acid solution, were optimized. An enhancement factor of 40.2 was achieved with 25 mL sample. The limit of detection (LOD) and quantification obtained under the optimum conditions were 12.5 and 41.0 {mu}g L{sup -1}, respectively. To validate the proposed methods two certified reference materials 681-I and BCR No. 288 were analyzed and the results were in good agreement with the certified values. The proposed method was successfully applied to determination of nickel in water samples, rice flour and black tea.

  10. A novel ionic liquid/micro-volume back extraction procedure combined with flame atomic absorption spectrometry for determination of trace nickel in samples of nutritional interest.

    Science.gov (United States)

    Dadfarnia, Shayesteh; Shabani, Ali Mohammad Haji; Bidabadi, Mahboubeh Shirani; Jafari, Abbas Ali

    2010-01-15

    A simple, highly sensitive and environment-friendly method for the determination of trace amount of nickel ion in different matrices is proposed. In the preconcentration step, the nickel from 10 mL of an aqueous solution was extracted into 500 microL of ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate [C(4)MIM][PF(6)], containing PAN as complexing agent. Subsequently, the PAN complex was back-extracted into 250 microL of nitric acid solution, and 100 microL of it was analyzed by flow injection flame atomic absorption spectrometry (FI-FAAS). The main parameter influencing the extraction and determination of nickel, such as pH, concentration of PAN, extraction time and temperature, ionic strength, and concentration of stripping acid solution, were optimized. An enhancement factor of 40.2 was achieved with 25 mL sample. The limit of detection (LOD) and quantification obtained under the optimum conditions were 12.5 and 41.0 microg L(-1), respectively. To validate the proposed methods two certified reference materials 681-I and BCR No. 288 were analyzed and the results were in good agreement with the certified values. The proposed method was successfully applied to determination of nickel in water samples, rice flour and black tea.

  11. A novel solidified floating organic drop microextraction method for preconcentration and determination of copper ions by flow injection flame atomic absorption spectrometry in water samples

    Directory of Open Access Journals (Sweden)

    Arpa Şahin Ç.

    2013-04-01

    Full Text Available A simple, rapid and inexpensive solidified floating organic drop microextraction (SFODME and flow injection flame atomic absorption spectrometric determination (FI-FAAS method for copper was developed. 3-amino-7-dimethylamino-2-methylphenazine (Neutral red, NR was used as the complexing agent. Several factors affecting the microextraction efficiency, such as, pH, NR and sodium dodecylbenzenesulfonate (SDBS concentration, extraction time, stirring rate, and temperature were investigated and optimized. Under optimized experimental conditions an enrichment factor of 541 was obtained for 100 mL of sample solution. The calibration graph was linear in the range of 0.5 – 20.0 ng mL–1 and the limit of detection (3s was 0.18 ng mL–1, the limit of quantification (10s was 0.58 ng mL–1. The relative standard deviation (RSD for 10 replicate measurements of 10 ng mL–1 copper was 2.7%. The developed method was successfully applied to the extraction and determination of copper in different certified reference materials (Estuarine water, Slew 3 and fortified water, TM 23.2 and real water samples and satisfactory results were obtained.

  12. On-line micro-volume introduction system developed for lower density than water extraction solvent and dispersive liquid-liquid microextraction coupled with flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Anthemidis, Aristidis N., E-mail: anthemid@chem.auth.gr [Laboratory of Analytical Chemistry, Department of Chemistry, Aristotle University, Thessaloniki 54124 (Greece); Mitani, Constantina; Balkatzopoulou, Paschalia; Tzanavaras, Paraskevas D. [Laboratory of Analytical Chemistry, Department of Chemistry, Aristotle University, Thessaloniki 54124 (Greece)

    2012-07-06

    Highlights: Black-Right-Pointing-Pointer A dispersive liquid-liquid micro extraction method for lead and copper determination. Black-Right-Pointing-Pointer A micro-volume transportation system for extractant solvent lighter than water. Black-Right-Pointing-Pointer Analysis of natural water samples. - Abstract: A simple and fast preconcentration/separation dispersive liquid-liquid micro extraction (DLLME) method for metal determination based on the use of extraction solvent with lower density than water has been developed. For this purpose a novel micro-volume introduction system was developed enabling the on-line injection of the organic solvent into flame atomic absorption spectrometry (FAAS). The effectiveness and efficiency of the proposed system were demonstrated for lead and copper preconcentration in environmental water samples using di-isobutyl ketone (DBIK) as extraction solvent. Under the optimum conditions the enhancement factor for lead and copper was 187 and 310 respectively. For a sample volume of 10 mL, the detection limit (3 s) and the relative standard deviation were 1.2 {mu}g L{sup -1} and 3.3% for lead and 0.12 {mu}g L{sup -1} and 2.9% for copper respectively. The developed method was evaluated by analyzing certified reference material and it was applied successfully to the analysis of environmental water samples.

  13. Cloud point extraction and flame atomic absorption spectrometric determination of cadmium(II), lead(II), palladium(II) and silver(I) in environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Ghaedi, Mehrorang, E-mail: m_ghaedi@mail.yu.ac.ir [Chemistry Department, Yasouj University, Yasouj 75914-353 (Iran, Islamic Republic of); Shokrollahi, Ardeshir [Chemistry Department, Yasouj University, Yasouj 75914-353 (Iran, Islamic Republic of); Niknam, Khodabakhsh [Chemistry Department, Persian Gulf University, Bushehr (Iran, Islamic Republic of); Niknam, Ebrahim; Najibi, Asma [Chemistry Department, Yasouj University, Yasouj 75914-353 (Iran, Islamic Republic of); Soylak, Mustafa [Chemistry Department, University of Erciyes, 38039 Kayseri (Turkey)

    2009-09-15

    The phase-separation phenomenon of non-ionic surfactants occurring in aqueous solution was used for the extraction of cadmium(II), lead(II), palladium(II) and silver(I). The analytical procedure involved the formation of understudy metals complex with bis((1H-benzo [d] imidazol-2yl)ethyl) sulfane (BIES), and quantitatively extracted to the phase rich in octylphenoxypolyethoxyethanol (Triton X-114) after centrifugation. Methanol acidified with 1 mol L{sup -1} HNO{sub 3} was added to the surfactant-rich phase prior to its analysis by flame atomic absorption spectrometry (FAAS). The concentration of BIES, pH and amount of surfactant (Triton X-114) was optimized. At optimum conditions, the detection limits of (3 sdb/m) of 1.4, 2.8, 1.6 and 1.4 ng mL{sup -1} for Cd{sup 2+}, Pb{sup 2+}, Pd{sup 2+} and Ag{sup +} along with preconcentration factors of 30 and enrichment factors of 48, 39, 32 and 42 for Cd{sup 2+}, Pb{sup 2+}, Pd{sup 2+} and Ag{sup +}, respectively, were obtained. The proposed cloud point extraction has been successfully applied for the determination of metal ions in real samples with complicated matrix such as radiology waste, vegetable, blood and urine samples.

  14. A Green Preconcentration Method for Determination of Cobalt and Lead in Fresh Surface and Waste Water Samples Prior to Flame Atomic Absorption Spectrometry

    Directory of Open Access Journals (Sweden)

    Naeemullah

    2012-01-01

    Full Text Available Cloud point extraction (CPE has been used for the preconcentration and simultaneous determination of cobalt (Co and lead (Pb in fresh and wastewater samples. The extraction of analytes from aqueous samples was performed in the presence of 8-hydroxyquinoline (oxine as a chelating agent and Triton X-114 as a nonionic surfactant. Experiments were conducted to assess the effect of different chemical variables such as pH, amounts of reagents (oxine and Triton X-114, temperature, incubation time, and sample volume. After phase separation, based on the cloud point, the surfactant-rich phase was diluted with acidic ethanol prior to its analysis by the flame atomic absorption spectrometry (FAAS. The enhancement factors 70 and 50 with detection limits of 0.26 μg L−1 and 0.44 μg L−1 were obtained for Co and Pb, respectively. In order to validate the developed method, a certified reference material (SRM 1643e was analyzed and the determined values obtained were in a good agreement with the certified values. The proposed method was applied successfully to the determination of Co and Pb in a fresh surface and waste water sample.

  15. Dispersive liquid-liquid microextraction based on solidification of floating organic drop for preconcentration and determination of trace amounts of copper by flame atomic absorption spectrometry.

    Science.gov (United States)

    Karadaş, Cennet; Kara, Derya

    2017-04-01

    A novel, simple, rapid, sensitive, inexpensive and environmentally friendly dispersive liquid-liquid microextraction method based on the solidification of a floating organic drop (DLLME-SFO) was developed for the determination of copper by flame atomic absorption spectrometry (FAAS). N-o-Vanillidine-2-amino-p-cresol was used as a chelating ligand and 1-undecanol was selected as an extraction solvent. The main parameters affecting the performance of DLLME-SFO, such as sample pH, volume of extraction solvent, extraction time, concentration of the chelating ligand, salt effect, centrifugation time and sample volume were investigated and optimized. The effect of interfering ions on the recovery of copper was also examined. Under the optimum conditions, the detection limit (3σ) was 0.93μgL(-1) for Cu using a sample volume of 20mL, yielding a preconcentration factor of 20. The proposed method was successfully applied to the determination of Cu in tap, river and seawater, rice flour and black tea samples as well as certified reference materials.

  16. Cloud point extraction and flame atomic absorption spectrometric determination of cadmium(II), lead(II), palladium(II) and silver(I) in environmental samples.

    Science.gov (United States)

    Ghaedi, Mehrorang; Shokrollahi, Ardeshir; Niknam, Khodabakhsh; Niknam, Ebrahim; Najibi, Asma; Soylak, Mustafa

    2009-09-15

    The phase-separation phenomenon of non-ionic surfactants occurring in aqueous solution was used for the extraction of cadmium(II), lead(II), palladium(II) and silver(I). The analytical procedure involved the formation of understudy metals complex with bis((1H-benzo [d] imidazol-2yl)ethyl) sulfane (BIES), and quantitatively extracted to the phase rich in octylphenoxypolyethoxyethanol (Triton X-114) after centrifugation. Methanol acidified with 1molL(-1) HNO(3) was added to the surfactant-rich phase prior to its analysis by flame atomic absorption spectrometry (FAAS). The concentration of BIES, pH and amount of surfactant (Triton X-114) was optimized. At optimum conditions, the detection limits of (3 sdb/m) of 1.4, 2.8, 1.6 and 1.4 ng mL(-1) for Cd(2+), Pb(2+), Pd(2+) and Ag(+) along with preconcentration factors of 30 and enrichment factors of 48, 39, 32 and 42 for Cd(2+), Pb(2+), Pd(2+) and Ag(+), respectively, were obtained. The proposed cloud point extraction has been successfully applied for the determination of metal ions in real samples with complicated matrix such as radiology waste, vegetable, blood and urine samples.

  17. Preconcentration of lead, cadmium and zinc on silica gel loaded with diethyldithiocarbamate prior to their determination by flame-atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Rio-Segade, S. [Dept. de Quimica Analitica y Alimentaria, Univ. de Vigo, Orense (Spain); Perez-Cid, B. [Dept. de Quimica Analitica y Alimentaria, Univ. de Vigo, Orense (Spain); Bendicho, C. [Dept. de Quimica Analitica y Alimentaria, Univ. de Vigo, Orense (Spain)

    1995-04-01

    A silica gel sorbent loaded with sodium diethyldithiocarbamate has been developed for the preconcentration of lead, cadmium and zinc prior to their determination by flame-atomic absorption spectrometry (FAAS). The sorption and desorption of the metal ions was studied under both static and dynamic conditions. The metal ions were quantitatively retained on the silica gel sorbent based on an equilibrium time of less than 1 min. In case of the batch method, the effects of pH, shaking time, amount of sorbent, and desorption time were investigated. Among the desorption agents studied, only EDTA in ammonium chloride/ammonia buffer yielded quantitative recoveries. Freundlich`s sorption isotherms determined for each metal show that sufficient sorption ability is obtained. The column method allows the preconcentration of metal ions from large sample volumes (e.g. 200 mL) using a flow rate of 5 mL min{sup -1}. The influence of foreign ions present in natural waters and saline solutions was examined. The reproducibility of the total analytical method, expressed as relative standard deviation (RSD) is 1.8, 0.5 and 0.6%, for lead, cadmium and zinc, respectively. (orig.)

  18. Supramolecular solvent-based extraction coupled with vortex-mixing for determination of palladium and silver in water samples by flame atomic absorption spectrometry.

    Science.gov (United States)

    Meng, Lifen; Cheng, Jiaxi; Yang, Yaling

    2014-01-01

    A simple and practical extraction method of supramolecular solvents (SUPRAS) was developed for separation and enrichment of trace amounts of palladium (Pd) and silver (Ag) in water samples prior to flame atomic absorption spectrometry (FAAS) analysis. The SUPRAS selected was made up of an aqueous solution containing tetrahydrofuran and nonanoic acid. Pd and Ag reacted with diethyldithiocarbamate to form hydrophobic chelates, which were extracted into the vesicles of SUPRAS. Different parameters such as the concentration of chelating agent, sample pH, supramolecular solvent and the effect of foreign ions were studied. Under the optimal conditions, the linear ranges of Pd and Ag were from 10 to 1,000 μg/L. The relative recoveries of Pd and Ag in tap and river water samples at the spiking level of 10 ug/mL ranged from 90.8 to 116%. The relative standard deviations were 3.6-4.0% (n = 9), the limits of detection were 2.8 and 1.9 μg/L and the enrichment factors were 36 and 18 for Pd and Ag, respectively. The quantification limits were 3.2 and 2.4 μg/L. The method was successfully applied to the determination of Pd and Ag in water samples.

  19. A green and efficient procedure for the preconcentration and determination of cadmium, nickel and zinc from freshwater, hemodialysis solutions and tuna fish samples by cloud point extraction and flame atomic absorption spectrometry.

    Science.gov (United States)

    Galbeiro, Rafaela; Garcia, Samara; Gaubeur, Ivanise

    2014-04-01

    Cloud point extraction (CPE) was used to simultaneously preconcentrate trace-level cadmium, nickel and zinc for determination by flame atomic absorption spectrometry (FAAS). 1-(2-Pyridilazo)-2-naphthol (PAN) was used as a complexing agent, and the metal complexes were extracted from the aqueous phase by the surfactant Triton X-114 ((1,1,3,3-tetramethylbutyl)phenyl-polyethylene glycol). Under optimized complexation and extraction conditions, the limits of detection were 0.37μgL(-1) (Cd), 2.6μgL(-1) (Ni) and 2.3μgL(-1) (Zn). This extraction was quantitative with a preconcentration factor of 30 and enrichment factor estimated to be 42, 40 and 43, respectively. The method was applied to different complex samples, and the accuracy was evaluated by analyzing a water standard reference material (NIST SRM 1643e), yielding results in agreement with the certified values.

  20. Evaluation of quartz tubes as atomization cells for gold determination by thermospray flame furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Morzan, Ezequiel; Piano, Ornela; Stripeikis, Jorge; Tudino, Mabel, E-mail: tudino@qi.fcen.uba.ar

    2012-11-15

    This work describes the development of a new analytical procedure able to determine gold by thermospray flame furnace atomic absorption spectrometry (TS-FF-AAS) using nickel tubes (NiT) and quartz tubes (QT) as atomization cells. Experiments involving changes in the flow injection operational parameters, reagent concentrations and sizes of the QT were performed in order to optimize sensitivity. Under the same operational conditions, it was observed that the employment of QT increases the sensitivity of gold determination when compared to the nickel tube. Since solutions of highly concentrated hydrochloric acid showed the best performance as carriers, quartz tubes were also preferred due to its greater tolerance to corrosion by mineral acids in comparison to NiT. In addition, changes in the internal diameter of the QT revealed an important improvement in sensitivity for smaller tubes. Under optimized conditions the main figures of merit showed values close to that of graphite furnace atomic absorption spectrometry with the addition of an excellent improvement of the sample throughput. They are: LOD (3 s): 0.004 {mu}g mL{sup -1}, sensitivity: 0.306 ({mu}g mL{sup -1}){sup -1}, RSD% (n = 10, 1 {mu}g mL{sup -1}): 2.5, linear range: 0.01-4 {mu}g mL{sup -1} and sample throughput: 72 h{sup -1}. This new method was employed for the determination of gold in homeopathic medicines with no need of sample digestion. Validation of the analytical results will be shown. A full discussion of the most relevant findings regarding the role of the atomization cell as a strategic key for improving sensitivity will be also provided. - Highlights: Black-Right-Pointing-Pointer Quartz tubes as furnaces in TS-FFAAS. Black-Right-Pointing-Pointer Small tubes for controlling radial dispersion. Black-Right-Pointing-Pointer Improved figures of merit for gold determination. Black-Right-Pointing-Pointer Analysis of homeopathic medicines.

  1. Determination of total magnesium in biological samples using electrothermal atomic absorption spectrometry

    Science.gov (United States)

    Hulanicki, Adam; Godlewska, Beata; Brzóska, Malgorzata

    1995-11-01

    Magnesium content is an important diagnostic parameter in medicine. It is recognized that its determination in one compartment is not sufficient for reliable information about the magnesium status in the body. In addition to the common procedures of magnesium determination in blood by flame atomic absorption spectrometry, the procedure of electrothermal atomization has also been developed and applied to the analysis of blood fractions, mononuclear cells and isolated nuclei of liver cells. Electrothermal atomization is preferred in cases where the sample size is limited and the magnesium content low. The total errors are in the order of 3-4%. Various techniques of sample pretreatment have been tested and direct dilution with 0.05 mol l -1 nitric acid was optimal when the samples were not mineralized. The calibration graph based on standards containing albumin was found to give the best results, as the form of magnesium in the samples may influence the ashing and atomization processes. Good agreement was obtained for determination of magnesium in standard serum. The results are compared with those obtained by the standard flame atomization technique.

  2. Method 200.12 - Determination of Trace Elements in Marine Waters by StabilizedTemperature Graphite Furnace Atomic Absorption

    Science.gov (United States)

    This method provides procedures for the determination of total recoverable elements by graphite furnace atomic absorption (GFAA) in marine waters, including estuarine, ocean and brines with salinities of up to 35 ppt.

  3. Indirect determination of vitamin B1 in vitamin tablets by flame atomic absorption spectrometry%FAAS法间接测定维生素片中维生素B1的含量

    Institute of Scientific and Technical Information of China (English)

    贾彩云; 王亦军; 魏国涛; 赵冰冰

    2012-01-01

    建立了火焰原子吸收光谱(FAAS)法间接测定维生素B片中的维生素B1含量的方法.用过量的Ag+与硫胺素盐酸盐的Cl-反应,产生AgCl沉淀,用火焰原子分光光度计测量上清液中剩余Ag+含量进而计算出样品中维生素B1的含量.方法回收率在98%~102%之间,相对标准偏差(RSD%)在1.05%~1.87%之间,方法操作简便,快速,重现性好.%An indirect method for the determination of vitamin B1 by flame atomic absorption spectrometry (FAAS).Excess Ag+ reacted with Cl- exists in thiamine hydrochloride to form AgCl, which was separated by centrifuge. Vitamin B1 was determined indirectly by determination of Ag+ in supernatant fluid. The average recoveries were between 98% and 102% ,and the relative standard deviations (RSD%) were 1.05%-1.87%. The results showed that the method was sensitive, accurate, convenient and quick, which can be used to detect Vitamin Bj in vitamin tablets.

  4. Towards FAA Certification of UAVs

    Science.gov (United States)

    Nelson, Stacy

    2003-01-01

    As of June 30, 2003, all Unmanned Aerial Vehicles (UAV), no matter how small, must adhere to the same FAA regulations as human-piloted aircraft. These regulations include certification for flying in controlled airspace and certification of flight software based on RTCA DO-178B. This paper provides an overview of the steps necessary to obtain certification, as well as a discussion about the challenges UAV's face when trying to meet these requirements. It is divided into two parts: 1) Certifications for Flying in Controlled Airspace; 2) Certification of Flight Software per RTCA DO-178B.

  5. ADSORPTION BEHAVIOR OF Pb(II) ON POTASSIUM HEXATITANATE WHISKER BY FAAS

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Based on the advantage of high surface area and strong adsorption ability of potassium hexatitanate whisker, a method to determine trace Pb(II) content by combining solid phase extraction with Flame atomic absorption spectrometry (FAAS) was established. The adsorptive behavior of potassium hexatitanate whisker to Pb(II), primary influencing factors of adsorption and elution and effect of coexistence ions were investigated systemically. The optimal analytical conditions were discussed and examined. It was found that the adsorption rate of potassium hexatitanate whisker to Pb(II) was 100% at pH 4.0. Pb(II) could be eluted from potassium tetratitanate whisker with HCl (2mol/L) under boiling water for 30min. The detection limit was 5.75ng/mL, and relative standard deviation was 1.66% (n=9, CPb=2.0μg/mL).

  6. ADSORPTION BEHAVIOR OF Pb(Ⅱ) ON POTASSIUM HEXATITANATE WHISKER BY FAAS

    Institute of Scientific and Technical Information of China (English)

    CHENG Yonghua; XU Wanzhen; YAN Yongsheng; JING Junjie

    2008-01-01

    Based on the advantage of high surface area and strong adsorption ability of potassium hexatitanate whisker, a method to determine trace Pb(Ⅱ) content by combining solid phase extraction with Flame atomic absorption spectrometry (FAAS) was established.The adsorptive behavior of potassium hexatitanate whisker to Pb(Ⅱ), primary influencing factors of adsorption and elation and effect of coexistence ions were investigated systemically.The optimal analytical conditions were discussed and examined.It was found that the adsorption rate of potassium hexatitanate whisker to Pb(Ⅱ) was 100% at pH 4.0.Pb(Ⅱ) could be elated from potassium tetratitanate whisker with HCI (2mol/L) under boiling water for 30min.The detection limit was 5.75ng/mL, and relative standard deviation was 1.66% (n=9, CPb=2.0μg/mL).

  7. Evaluation of lubricating oil preparation procedures for the determination of Al, Ba, Mo, Si and V by high-resolution continuum source FAAS.

    Science.gov (United States)

    Amorim Filho, Volnei Resta; Gomes Neto, José Anchieta

    2009-01-01

    Microwave-assisted acid decomposition and oil-in-water emulsification were evaluated as sample pretreatment procedures to determine Al, Ba, Mo, Si and V in lubricating oils by high-resolution continuum source flame atomic absorption spectrometry (HR-CS FAAS). Average recoveries of Al, Ba and V in oil digests (107, 103 and 101%) were close to those obtained for emulsions prepared in kerosene medium (94, 113 and 95%). Average recoveries for Mo were close to 105 and 46% for emulsions and digests, respectively. Improved average recoveries (101%) were obtained for Mo in digests using the analyte addition technique. Silicon was successfully quantified only in digested samples. Limits of quantification for Al, Ba, Mo and V were 1.4, 31.5, 1.5 and 11.4-fold lower than those obtained by line-source FAAS. Enhanced sensitivity, multi-elemental capability, and high sample throughput are among the main advantages of HR-CS FAAS in comparison with the line-source FAAS technique.

  8. Alternative approaches to correct interferences in the determination of boron in shrimps by electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Pasias, I.N.; Pappa, Ch.; Katsarou, V.; Thomaidis, N.S., E-mail: ntho@chem.uoa.gr; Piperaki, E.A.

    2014-02-01

    The aim of this study is to propose alternative techniques and methods in combination with the classical chemical modification to correct the major matrix interferences in the determination of boron in shrimps. The performance of an internal standard (Ge) for the determination of boron by the simultaneous multi-element atomic absorption spectrometry was tested. The use of internal standardization increased the recovery from 85.9% to 101% and allowed a simple correction of errors during sampling preparation and heating process. Furthermore, a new preparation procedure based on the use of citric acid during digestion and dilution steps improved the sensitivity of the method and decreased the limit of detection. Finally, a comparative study between the simultaneous multi-element atomic absorption spectrometry with a longitudinal Zeeman-effect background correction system, equipped with a transversely-heated graphite atomizer and the single element atomic absorption spectrometry with a D{sub 2} background correction system, equipped with an end-heated graphite atomizer was undertaken to investigate the different behavior of boron in both techniques. Different chemical modifiers for the determination of boron were tested with both techniques. Ni-citric acid and Ca were the optimal chemical modifiers when simultaneous multi-element atomic absorption spectrometry and single-element atomic absorption spectrometry were used, respectively. By using the single-element atomic absorption spectrometry, the calculated characteristic mass was 220 pg and the calculated limit of detection was 370 μg/kg. On the contrary, with simultaneous multi-element atomic absorption spectrometry, the characteristic mass was 2200 pg and the limit of detection was 5.5 mg/kg. - Highlights: • New approaches were developed to cope with interferences of B determination by ETAAS • Ge was used as internal standard for the determination of B by simultaneous ETAAS • Citric acid was used during

  9. Novel atomic absorption spectrometric and rapid spectrophotometric methods for the quantitation of paracetamol in saliva: Application to pharmacokinetic studies

    Directory of Open Access Journals (Sweden)

    Issa M

    2008-01-01

    Full Text Available A novel atomic absorption spectrometric method and two highly sensitive spectrophotometric methods were developed for the determination of paracetamol. These techniques based on the oxidation of paracetamol by iron (III (method I; oxidation of p-aminophenol after the hydrolysis of paracetamol (method II. Iron (II then reacts with potassium ferricyanide to form Prussian blue color with a maximum absorbance at 700 nm. The atomic absorption method was accomplished by extracting the excess iron (III in method II and aspirates the aqueous layer into air-acetylene flame to measure the absorbance of iron (II at 302.1 nm. The reactions have been spectrometrically evaluated to attain optimum experimental conditions. Linear responses were exhibited over the ranges 1.0-10, 0.2-2.0 and 0.1-1.0 µg/ml for method I, method II and atomic absorption spectrometric method, respectively. A high sensitivity is recorded for the proposed methods I and II and atomic absorption spectrometric method value indicate: 0.05, 0.022 and 0.012 µg/ml, respectively. The limit of quantitation of paracetamol by method II and atomic absorption spectrometric method were 0.20 and 0.10 µg/ml. Method II and the atomic absorption spectrometric method were applied to demonstrate a pharmacokinetic study by means of salivary samples in normal volunteers who received 1.0 g paracetamol. Intra and inter-day precision did not exceed 6.9%.

  10. Direct determination of arsenic in petroleum derivatives by graphite furnace atomic absorption spectrometry: A comparison between filter and platform atomizers

    Energy Technology Data Exchange (ETDEWEB)

    Becker, Emilene; Rampazzo, Roger T.; Dessuy, Morgana B. [Instituto de Quimica, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves, 9500, 91501-970 Porto Alegre, RS (Brazil); Vale, Maria Goreti R., E-mail: mgrvale@ufrgs.br [Instituto de Quimica, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves, 9500, 91501-970 Porto Alegre, RS (Brazil); Instituto Nacional de Ciencia e Tecnologia do CNPq - INCT de Energia e Ambiente, Universidade Federal da Bahia, Salvador, BA (Brazil); Silva, Marcia M. da [Instituto de Quimica, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves, 9500, 91501-970 Porto Alegre, RS (Brazil); Welz, Bernhard [Instituto Nacional de Ciencia e Tecnologia do CNPq - INCT de Energia e Ambiente, Universidade Federal da Bahia, Salvador, BA (Brazil); Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil); Katskov, Dmitri A. [Tshwane University of Technology (TUT), Faculty of Science, Chemistry Department, Pretoria 0001 (South Africa)

    2011-05-15

    In the present work a direct method for the determination of arsenic in petroleum derivatives has been developed, comparing the performance of a commercial transversely heated platform atomizer (THPA) with that of a transversely heated filter atomizer (THFA). The THFA results in a reduction of background absorption and an improved sensitivity as has been reported earlier for this atomizer. The mixture of 0.1% (m/v) Pd + 0.03% (m/v) Mg + 0.05% (v/v) Triton X-100 was used as the chemical modifier for both atomizers. The samples (naphtha, gasoline and petroleum condensate) were stabilized in the form of a three-component solution (detergentless microemulsion) with the sample, propan-1-ol and 0.1% (v/v) HNO{sub 3} in a ratio of 3.0:6.4:0.6. The characteristic mass of 13 pg found in the THFA was about a factor of two better than that of 28 pg obtained with the THPA; however, the limits of detection (LOD) and quantification (LOQ) were essentially the same for both atomizers (1.9 and 6.2 {mu}g L{sup -1}, respectively, for THPA, and 1.8 and 5.9 {mu}g L{sup -1}, respectively, for THFA) due to the increased noise observed with the THFA. A possible explanation for that is a partial blockage of the radiation from the hollow cathode lamp by the narrow inner diameter of this tube and the associated loss of radiation energy. Due to the lack of an appropriate certified reference material, recovery tests were carried out with inorganic and organic arsenic standards and the results were between 89% and 111%. The only advantage of the THFA found in this work was a reduction of the total analysis time by about 20% due to the 'hot injection' that could be realized with this furnace. The arsenic concentrations varied from < LOQ to 43.3 {mu}g L{sup -1} in the samples analyzed in this work.

  11. Absorption spectroscopy characterization measurements of a laser-produced Na atomic beam

    Energy Technology Data Exchange (ETDEWEB)

    Ching, C.H.; Bailey, J.E.; Lake, P.W.; Filuk, A.B.; Adams, R.G.; McKenney, J.

    1996-06-01

    This work describes a pulsed Na atomic beam source developed for spectroscopic diagnosis of a high-power ion diode on the Particle Beam Fusion Accelerator II. The goal is to produce a {approximately} 10{sup 12}-cm{sup {minus}3}-density Na atomic beam that can be injected into the diode acceleration gap to measure electric and magnetic fields from the Stark and Zeeman effects through laser-induced-fluorescence or absorption spectroscopy. A {approximately} 10 ns fwhm, 1.06 {micro}m, 0.6 J/cm{sup 2} laser incident through a glass slide heats a Na-bearing thin film, creating a plasma that generates a sodium vapor plume. A {approximately} 1 {micro}sec fwhm dye laser beam tuned to 5,890 {angstrom} is used for absorption measurement of the Na I resonant doublet by viewing parallel to the film surface. The dye laser light is coupled through a fiber to a spectrograph with a time-integrated CCD camera. A two-dimensional mapping of the Na vapor density is obtained through absorption measurements at different spatial locations. Time-of-flight and Doppler broadening of the absorption with {approximately} 0.1 {angstrom} spectral resolution indicate that the Na neutral vapor temperature is about 0.5 to 2 eV. Laser-induced-fluorescence from {approximately} 1 {times} 10{sup 12}-cm{sup {minus}3} Na I 3s-3p lines observed with a streaked spectrograph provides a signal level sufficient for {approximately} 0.06 {angstrom} wavelength shift measurements in a mock-up of an ion diode experiment.

  12. Determination of vanadium in mussels by electrothermal atomic absorption spectrometry without chemical modifiers

    Energy Technology Data Exchange (ETDEWEB)

    Saavedra, Y.; Fernandez, P. [Centro de Control do Medio Marino, Peirao de Vilaxoan s/n, Vilagarcia de Arousa, 36611 Pontevedra (Spain); Gonzalez, A. [Departamento de Quimica Analitica, Nutricion y Bromatologia, Facultad de Quimica, 15706, Santiago de Compostela (Spain)

    2004-05-01

    A method was developed for the quantitative determination of total vanadium concentration in mussels via electrothermal atomic absorption spectrometry (ETAAS). After the microwave digestion of the samples, a program using temperatures of 1600 C and 2600 C for ashing and atomization respectively, without any matrix modifiers, allowed us to obtain results that were satisfactory since they agreed closely with certified reference material values. The detection limit was 0.03 mg kg{sup -1} (dry weight), indicating that the method is suitable for the analysis of mussel samples. This determination was compared with matrix modifiers that have been reported previously. The method was applied to various cultivated and wild mussels from the Galician coast, yielding levels below 1 mg kg{sup -1} (wet weight). (orig.)

  13. Determination of ruthenium in pharmaceutical compounds by graphite furnace atomic absorption spectroscopy.

    Science.gov (United States)

    Jia, Xiujuan; Wang, Tiebang; Bu, Xiaodong; Tu, Qiang; Spencer, Sandra

    2006-04-11

    A graphite furnace atomic absorption (GFAA) spectrometric method for the determination of ruthenium (Rh) in solid and liquid pharmaceutical compounds has been developed. Samples are dissolved or diluted in dimethyl sulfoxide (DMSO) without any other treatment before they were analyzed by GFAA with a carefully designed heating program to avoid pre-atomization signal loss and to achieve suitable sensitivity. Various inorganic and organic solvents were tested and compared and DMSO was found to be the most suitable. In addition, ruthenium was found to be stable in DMSO for at least 5 days. Spike recoveries ranged from 81 to 100% and the limit of quantitation (LOQ) was determined to be 0.5 microg g(-1) for solid samples or 0.005 microg ml(-1) for liquid samples based a 100-fold dilution. The same set of samples was also analyzed by ICP-MS with a different sample preparation method, and excellent agreement was achieved.

  14. [Determination of trace selenium in edible fungi with graphite furnace atomic absorption spectroscopy].

    Science.gov (United States)

    Tie, Mei; Zhang, Wei; Li, Jing; Jing, Kui; Zang, Shu-liang; Li, Hua-wei

    2006-01-01

    In the present article, samples were digested by a quartz high-pressure digestion pot, reducing the loss of selenium in digestion. The content of selenium in edible fungi was determined by using graphite furnace atomic absorption spectroscopy, and the results showed that when the content of selenium in edible fungi was determined by using 1% Ni(NO3)2 as a matrix modifier, ashing temperature of 500 degreed C, and atomization temperature of 2 500 degrees C, and rectifying background by deuterium light, the recovery was in the range of 92.1%-115.5%, the relative standard deviation of the method was 1.28%, and the limit of detection was 15.8 microg x L(-1). The method was suitable for the determination of trace selenium in edible fungi with the advantages of being simple, rapid, sensitive, stable and accurate etc., and the results were satisfactory.

  15. The determination of aluminum, copper, iron, and lead in glycol formulations by atomic absorption spectroscopy

    Science.gov (United States)

    1977-01-01

    Initial screening tests and the results obtained in developing procedures to determine Al, Cu, Fe, and Pb in glycol formulations are described. Atomic absorption completion was selected for Cu, Fe and Pb, and after comparison with emission spectroscopy, was selected for Al also. Before completion, carbon, iron, and lead are extracted with diethyl dithio carbamate (DDC) into methyl isobutyl ketone (MIBK). Aluminum was also extracted into MIBK using 8-hydroxyquinoline as a chelating agent. As little as 0.02 mg/l carbon and 0.06 mg/l lead or iron may be determined in glycol formulations. As little as 0.3 mg/l aluminum may be determined.

  16. Iron analysis in atmospheric water samples by atomic absorption spectroscopy (AAS) in water-methanol.

    Science.gov (United States)

    Sofikitis, A M; Colin, J L; Desboeufs, K V; Losno, R

    2004-01-01

    To distinguish between Fe(II) and Fe(III) species in atmospheric water samples, we have adapted an analytical procedure based on the formation of a specific complex between Fe(II) and ferrozine (FZ) on a chromatographic column. After elution of Fe(III), the Fe(II) complex is recovered with water-methanol (4:1). The possibility of trace iron measurements in this complex medium by graphite-furnace atomic-absorption spectrometry has been investigated. A simplex optimization routine was required to complete the development of the analytical method.

  17. Determination of traces of silver in waters by anion exchange and atomic absorption spectrophotometry

    Science.gov (United States)

    Chao, T.T.; Fishman, M. J.; Ball, J.W.

    1969-01-01

    A method has been developed for the accurate determination of 0.1-1 ??g of silver per liter of water. The method permits stabilization of silver in water without loss to container walls. Optimum conditions have been established for the complete recovery of silver from water with an anion-exchange column, for quantitative elution of silver from the resin, and for measurement of silver by atomic absorption spectrophotometry after chelation with ammonium pyrrolidine dithiocarbamate and extraction of the chelate with MIBK. Silver in the 1-10 ??g 1 range can be determined by extraction without pre-concentration on an ion-exchange resin. ?? 1969.

  18. Determination of heavy metals in solid emission and immission samples using atomic absorption spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Fara, M.; Novak, F. [EGU Prague, PLC, Bichovice, Prague (Czechoslovakia)

    1995-12-01

    Both flame and electrothermal methods of atomic absorption spectroscopy (AAS) have been applied to the determination of Al, As, Be, Ca, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, TI, Se, V and Zn in emission and emission (deposition) samples decomposed in open PTFE test-tubes by individual fuming-off hydrofluoric, perchloroic and nitric acid. An alternative hydride technique was also used for As and Se determination and Hg was determined using a self-contained AAS analyzer. A graphite platform proved good to overcome non-spectral interferences in AAS-ETA. Methods developed were verified by reference materials (inc. NBS 1633a).

  19. Exploiting flow Injection and sequential injection schemes for trace metal determinations by electrothermal atomic absorption spectrometry

    DEFF Research Database (Denmark)

    Hansen, Elo Harald

    Determination of low or trace-level amounts of metals by electrothermal atomic absorption spectrometry (ETAAS) often requires the use of suitable preconcentration and/or separation procedures in order to attain the necessary sensitivity and selectivity. Such schemes are advantageously executed....../preconcentration procedures have been suggested and applied, such as liquid-liquid extraction, (co)precipitation with collection in knotted reactors, adsorption, hydride generation, or ion-exchange. Selected examples of some of these procedures will be discussed. Emphasis will be placed on the use of FI...

  20. Neutral atomic absorption lines and far-UV extinction: Possible implications for depletions and grain parameters

    Science.gov (United States)

    Welty, Daniel E.

    1990-01-01

    Researchers examine nine lines of sight within the Galaxy and one in the Large Magellanic Cloud (LMC) for which data on both neutral atomic absorption lines (Snow 1984; White 1986; Welty, Hobbs, and York 1989) and far UV extinction (Bless and Savage 1972; Jenkins, Savage, and Spitzer 1986) are available, in order to test the assumption that variations in gamma/alpha will cancel in taking ratios of the ionization balance equation, and to try to determine to what extent that assumption has affected the aforementioned studies of depletions and grain properties.

  1. A simple and fast method for assessment of the nitrogen–phosphorus–potassium rating of fertilizers using high-resolution continuum source atomic and molecular absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Bechlin, Marcos André; Fortunato, Felipe Manfroi; Moutinho da Silva, Ricardo; Ferreira, Edilene Cristina; Gomes Neto, José Anchieta, E-mail: anchieta@iq.unesp.br

    2014-11-01

    The determination of N, P, and K in fertilizers by high-resolution continuum source flame atomic and molecular absorption spectrometry is proposed. Under optimized conditions, measurements of the diatomic molecules NO and PO at 215.360 and 247.620 nm, respectively, and K using the wing of the alternative line at 404.722 nm allowed calibration curves to be constructed in the ranges 500–5000 mg L{sup −1} N (r = 0.9994), 100–2000 mg L{sup −1} P (r = 0.9946), and 100–2500 mg L{sup −1} K (r = 0.9995). Commercial fertilizers were analyzed by the proposed method and the concentrations of N, P, and K were found to be in agreement with those obtained by Kjeldahl, spectrophotometric, and flame atomic emission spectrometry methods, respectively, at a 95% confidence level (paired t-test). A phosphate rock certified reference material (CRM) was analyzed and the results for P and K were in agreement with the reference values. Recoveries from spiked CRM were in the ranges 97–105% (NO{sub 3}{sup −}-N), 95–103% (NH{sub 4}{sup +}-N), 93–103% (urea-N), 99–108% (P), and 99–102% (K). The relative standard deviations (n = 12) for N, P, and K were 6, 4, and 2%, respectively. - Highlights: • A single technique is proposed to analyze NPK fertilizer. • HR-CS FAAS is proposed for the first time for N, P and K determination in fertilizers. • The method employs the same sample preparation and dilution for the three analytes. • Addition of H{sub 2}O{sub 2} allows analysis of fertilizers with different nitrogen species. • Proposal provides advantages over traditional methods in terms of cost and time.

  2. Method for the determination of cobalt from biological products with graphite furnace atomic absorption spectrometer

    Science.gov (United States)

    Zamfir, Oana-Liliana; Ionicǎ, Mihai; Caragea, Genica; Radu, Simona; Vlǎdescu, Marian

    2016-12-01

    Cobalt is a chemical element with symbol Co and atomic number 27 and atomic weight 58.93. 59 Co is the only stable cobalt isotope and the only isotope to exist naturally on Earth. Cobalt is the active center of coenzymes called cobalamin or cyanocobalamin the most common example of which is vitamin B12. Vitamin B12 deficiency can potentially cause severe and irreversible damage, especially to the brain and nervous system in the form of fatigue, depression and poor memory or even mania and psychosis. In order to study the degree of deficiency of the population with Co or the correctness of treatment with vitamin B12, a modern optoelectronic method for the determination of metals and metalloids from biological samples has been developed, Graphite Furnace - Atomic Absorption Spectrometer (GF- AAS) method is recommended. The technique is based on the fact that free atoms will absorb light at wavelengths characteristic of the element of interest. Free atoms of the chemical element can be produced from samples by the application of high temperatures. The system GF-AAS Varian used as biological samples, blood or urine that followed the digest of the organic matrix. For the investigations was used a high - performance GF-AAS with D2 - background correction system and a transversely heated graphite atomizer. As result of the use of the method are presented the concentration of Co in the blood or urine of a group of patient in Bucharest. The method is sensitive, reproducible relatively easy to apply, with a moderately costs.

  3. Low-resolution continuum source simultaneous multi-element electrothermal atomic absorption spectrometry: steps into practice

    Energy Technology Data Exchange (ETDEWEB)

    Katskov, Dmitri, E-mail: katskovda@tut.ac.za

    2015-03-01

    The theory and practical problems of continuum source simultaneous multi-element electrothermal atomic absorption spectrometry (SMET AAS) are discussed by the example of direct analysis of underground water. The experimental methodology is based on pulse vaporization of the sample in a fast heated graphite tube and measurement of transient absorption of continuum spectrum radiation from D{sub 2} and Xe lamps within 200–400 nm wavelengths range with a low resolution spectral instrument and linear charge-coupled device. The setup permits the acquisition of 200 spectra during 1 s atomization pulse. Respective data matrix absorbance vs wavelength/time is employed for the quantification of elements in the sample. The calculation algorithm developed includes broad band and continuum background correction, linearization of function absorbance vs. concentration of atomic vapor and integration of thus modified absorbance at the resonance lines of the elements to be determined. Practical application shows that the method can be employed for the direct simultaneous determination of about 20 elements above microgram per liter level within 3–5 orders of the magnitude concentration range. The investigated sources of measurement errors are mainly associated with the atomization and vapor transportation problems, which are aggravated for the simultaneous release of major and minor sample constituents. Respective corrections concerning the selection of analytical lines, optimal sampling volume, matrix modification and cleaning of the atomizer have been introduced in the SMET AAS analytical technology. Under the optimized experimental conditions the calibration curves in Log-Log coordinates for all the investigated analytes in the single or multi-element reference solutions are approximated by the first order equations. The use of these equations as permanent characteristics of the setup enables instant quantification of Al, Ca, Co, Cr, Cu, Fe, Mg, Mn and Ni in the underground

  4. Slurry analysis after lead collection on a sorbent and its determination by electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Baysal, Asli; Tokman, Nilgun [Istanbul Technical University, Faculty of Science and Letters, Department of Chemistry, 34469 Maslak-Istanbul (Turkey); Akman, Suleyman [Istanbul Technical University, Faculty of Science and Letters, Department of Chemistry, 34469 Maslak-Istanbul (Turkey)], E-mail: akmans@itu.edu.tr; Ozeroglu, Cemal [Istanbul University, Department of Chemistry, Faculty of Engineering, 34320 Avcilar-Istanbul (Turkey)

    2008-02-11

    In this study, in order to eliminate the drawbacks of elution step and to reach higher enrichment factors, a novel preconcentration/separation technique for the slurry analysis of sorbent loaded with lead prior to its determination by electrothermal atomic absorption spectrometry was described. For this purpose, at first, lead was collected on ethylene glycol dimethacrylate methacrylic acid copolymer (EGDMA-MA) treated with ammonium pyrolidine dithiocarbamate (APDC) by conventional batch technique. After separation of liquid phase, slurry of the sorbent was prepared and directly pipetted into graphite furnace of atomic absorption spectrophotometer. Optimum conditions for quantitative sorption and preparation of the slurry were investigated. A 100-fold enrichment factor could be easily reached. The analyte element in certified sea-water and Bovine-liver samples was determined in the range of 95% confidence level. The proposed technique was fast and simple and the risks of contamination and analyte loss were low. Detection limit (3{delta}) for Pb was 1.67 {mu}g l{sup -1}.

  5. Determination of Elements by Atomic Absorption Spectrometry in Medicinal Plants Employed to Alleviate Common Cold Symptoms

    Institute of Scientific and Technical Information of China (English)

    F Zehra Küçükbay; Ebru Kuyumcu

    2014-01-01

    Eleven important medicinal plants generally used by the people of Turkey for the treatment of com-mon cold have been studied for their mineral contents .Eleven minor and major elements (essential ,non-essen-tial and toxic) were identified in the Asplenium adiantum-nigrum L .,Althaea of ficinalis L .,Verbascum phlomoides L .,Euphorbiachamaesyce L .,Zizyphus jujube Miller ,Peganum harmala L .,Arum dioscori-dis Sm .,Sambucus nigra L .,Piper longum L .,Tussilago farfara L .and Elettariacardamomum Maton by employing flame atomic absorption and emission spectrometry and electro-thermal atomic absorption spectrom-etry .Microwave digestion procedure for total concentration was applied under optimized conditions for dissolu-tion of medicinal plants .Plant based biological certified reference materials (CRMs) served as standards for quantification .These elements are found to be present in varying concentrations in the studied plants .The baseline data presented in this work can be used in understanding the role of essential ,non-essential and toxic elements in nutritive ,preventive and therapeutic properties of medicinal plants .

  6. Quantitation of a novel metalloporphyrin drug in plasma by atomic absorption spectroscopy.

    Science.gov (United States)

    Hoffman, K L; Feng, M R; Rossi, D T

    1999-03-01

    A bioanalytical method to quantify cobalt mesoporphyrin (CoMP), a novel therapeutic agent, in plasma has been developed and validated. The approach involves atomic absorption spectroscopy to determine total cobalt in a sample and a back-calculation of the amount of compound present. Endogenous plasma cobalt concentrations were small ( <0.2 ng/ml(-1) Co in rat plasma) in comparison to the quantitation limit (4.5 ng/ml(-1) Co). The inter-day imprecision of the method was 10.0% relative standard deviation (RSD) and the inter-day bias was +/- 8.0% relative error (RE) over a standard curve range of 4.5- 45.0 ng/ml(-1) Co. Because it quantifies total cobalt, the method cannot differentiate between parent drug and metabolites, but negligible metabolism allows reliable estimates of the actual parent drug concentration. A correlation study between the atomic absorption method and 14C-radiometry demonstrated excellent agreement (r = 0.9868, slope = 1.041 +/- 0.028, intercept = 223.7 +/- 190.0) and further substantiated the accuracy of the methods. Methodology was successfully applied to a pharmacokinetic study of CoMP in rat, with pharmacokinetic parameter estimation. The elimination half-lives, after intra-muscular and subcutaneous administration, were 7.7 and 8.8 days, respectively.

  7. Determination of metal concentration in fat supplements for swine nutrition by atomic absorption spectroscopy.

    Science.gov (United States)

    Cocchi, Marina; Faeti, Valerio; Manfredini, Matteo; Manzini, Daniela; Marchetti, Andrea; Sighinolfi, Simona

    2005-01-01

    The presence of some essential and toxic metals in fat supplements for swine diet was investigated. Collected samples represented a relevant production of the Italian industry. In particular, some samples were enriched with antioxidants or waste cooking oils. The method for the determination of Ca, Cu, Cd, Fe, Mg, Mn, Ni, Pb, and Zn in fat samples was developed by means of a certified reference material (CRM 186) and a representative fatty sample (RFS). All samples were digested in closed vessels in a microwave oven and then analyzed by flame atomic absorption or graphite furnace atomic absorption spectrometry. The entire analytical method provided a satisfactory repeatability and reproducibility confirmed by agreement between the experimental recovery data obtained for the CRM 186 sample and, with the method of standard additions, for the RFS material. The samples generally showed a small amount of metals compared with the recommended daily intake for the essential elements. On the other hand, some samples contained a significant concentration, from an analytical point of view, of Cd, Ni, and Pb. Principal component analysis (PCA) was applied to inspect the experimental data obtained from samples analysis. Basically no differences were detected in terms of metal concentration among the fat supplements analyzed.

  8. Use of flameless atomic absorption spectroscopy in immune cytolysis for nonradioactive determination of killer cell activity.

    Science.gov (United States)

    Borella, P; Bargellini, A; Salvioli, S; Cossarizza, A

    1996-02-01

    We describe here a novel method to evaluate natural killer (NK) cytolytic activity by use of flameless atomic absorption spectroscopy (GF-AAS). This technique may be adopted for use in laboratories equipped with electrothermal atomic absorption spectrometers. Nonradioactive Cr as Na2CrO4 was used to label target cells (K562), and cell lysis was evaluated by measuring Cr released after 4 h of incubation with the effectors. We selected 520 micrograms/L as the optimal dose for labeling targets, between 12 and 20 h as the optimal incubation time, and 10(4) cells as the optimal target size. Advantages of this method include: (a) exclusion of radioactive tracer, with no risk for workers; (b) limited costs; (c) high sensitivity and reproducibility; (d) possibility to store samples; and (e) better control of Cr used for labeling cells due to well-determined, fixed Cr concentrations in the range of nontoxic and linear cellular uptake. Comparison with data obtained by conventional 51Cr labeling of targets killed by the same effectors was excellent, yielding comparable results and corroborating the method.

  9. Shock-tube measurements of excited oxygen atoms using cavity-enhanced absorption spectroscopy.

    Science.gov (United States)

    Nations, Marcel; Wang, Shengkai; Goldenstein, Christopher S; Sun, Kai; Davidson, David F; Jeffries, Jay B; Hanson, Ronald K

    2015-10-10

    We report the use of cavity-enhanced absorption spectroscopy (CEAS) using two distributed feedback diode lasers near 777.2 and 844.6 nm for sensitive, time-resolved, in situ measurements of excited-state populations of atomic oxygen in a shock tube. Here, a 1% O2/Ar mixture was shock-heated to 5400-8000 K behind reflected shock waves. The combined use of a low-finesse cavity, fast wavelength scanning of the lasers, and an off-axis alignment enabled measurements with 10 μs time response and low cavity noise. The CEAS absorption gain factors of 104 and 142 for the P35←S520 (777.2 nm) and P0,1,23←S310 (844.6 nm) atomic oxygen transitions, respectively, significantly improved the detection sensitivity over conventional single-pass measurements. This work demonstrates the potential of using CEAS to improve shock-tube studies of nonequilibrium electronic-excitation processes at high temperatures.

  10. [The application of atomic absorption spectrometry in automatic transmission fault detection].

    Science.gov (United States)

    Chen, Li-dan; Chen, Kai-kao

    2012-01-01

    The authors studied the innovative applications of atomic absorption spectrometry in the automatic transmission fault detection. After the authors have determined Fe, Cu and Cr contents in the five groups of Audi A6 main metal in automatic transmission fluid whose travel course is respectively 10-15 thousand kilometers, 20-26 thousand kilometers, 32-38 thousand kilometers, 43-49 thousand kilometers, and 52-58 thousand kilometers by atomic absorption spectrometry, the authors founded the database of primary metal content in the Audi A6 different mileage automatic transmission fluid (ATF). The research discovered that the main metal content in the automatic transmission fluid increased with the vehicles mileage and its normal metal content level in the automatic transmission fluid is between the two trend lines. The authors determined the main metal content of automatic transmission fluid which had faulty symptoms and compared it with its database value. Those can not only judge the wear condition of the automatic transmission which had faulty symptoms but also help the automobile detection and maintenance personnel to diagnose automatic transmission failure reasons without disintegration. This reduced automobile maintenance costs, and improved the quality of automobile maintenance.

  11. Combination of dispersive liquid-liquid microextraction with flame atomic absorption spectrometry using microsample introduction for determination of lead in water samples

    Energy Technology Data Exchange (ETDEWEB)

    Naseri, Mohammad Taghi; Hemmatkhah, Payam; Hosseini, Mohammad Reza Milani [Department of Analytical Chemistry, Faculty of Chemistry, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Electroanalytical Chemistry Research Center, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Assadi, Yaghoub [Department of Analytical Chemistry, Faculty of Chemistry, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Electroanalytical Chemistry Research Center, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of)], E-mail: y_assadi@iust.ac.ir

    2008-03-03

    The dispersive liquid-liquid microextraction (DLLME) was combined with the flame atomic absorption spectrometry (FAAS) for determination of lead in the water samples. Diethyldithiophosphoric acid (DDTP), carbon tetrachloride and methanol were used as chelating agent, extraction solvent and disperser solvent, respectively. A new FAAS sample introduction system was employed for the microvolume nebulization of the non-flammable chlorinated organic extracts. Injection of 20 {mu}L volumes of the organic extract into an air-acetylene flame provided very sensitive spike-like and reproducible signals. Some effective parameters on the microextraction and the complex formation were selected and optimized. These parameters include extraction and disperser solvent type as well as their volume, extraction time, salt effect, pH and amount of the chelating agent. Under the optimized conditions, the enrichment factor of 450 was obtained from a sample volume of 25.0 mL. The enhancement factor, calculated as the ratio of the slopes of the calibration graphs with and without preconcentration, which was about 1000. The calibration graph was linear in the range of 1-70 {mu}g L{sup -1} with a detection limit of 0.5 {mu}g L{sup -1}. The relative standard deviation (R.S.D.) for seven replicate measurements of 5.0 and 50 {mu}g L{sup -1} of lead were 3.8 and 2.0%, respectively. The relative recoveries of lead in tap, well, river and seawater samples at the spiking level of 20 {mu}g L{sup -1} ranged from 93.8 to 106.2%. The characteristics of the proposed method were compared with those of the liquid-liquid extraction (LLE), cloud point extraction (CPE), on-line and off-line solid-phase extraction (SPE) as well as co-precipitation, based on bibliographic data. Operation simplicity, rapidity, low cost, high enrichment factor, good repeatability, and low consumption of the extraction solvent at a microliter level are the main advantages of the proposed method.

  12. Heavy metal adsorptivity of calcium-alginate-modified diethylenetriamine-silica gel and its application to a flow analytical system using flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Mori, Masanobu, E-mail: mori@gunma-u.ac.jp [Graduate School of Science and Technology, Gunma University, 1-5-1, Tenjin-cho, Kiryu 376-8515, Japan, (Japan); Suzuki, Toshinobu; Sugita, Tsuyoshi; Nagai, Daisuke [Graduate School of Science and Technology, Gunma University, 1-5-1, Tenjin-cho, Kiryu 376-8515, Japan, (Japan); Hirayama, Kazuo [College of Engineering, Nihon University, 1 Nakagawara, Tokusada, Tamuramachi, Koriyama, Fukushima 963-8642 (Japan); Onozato, Makoto; Itabashi, Hideyuki [Graduate School of Science and Technology, Gunma University, 1-5-1, Tenjin-cho, Kiryu 376-8515, Japan, (Japan)

    2014-08-20

    Highlights: • Calcium-alginate-modified dien-silica gel adsorbed multivalent metal ions. • Metal ions adsorbed on CaAD were eluted using low acidic concentrations. • Flow system with CaAD-packed column enriched metal concentrations up to 50-fold. - Abstract: This study aimed to evaluate the heavy metal adsorptivity of calcium-alginate-modified diethylenetriamine-silica gel (CaAD) and incorporate this biosorbent into a flow analytical system for heavy metal ions using flame atomic absorption spectrometry (FAAS). The biosorbent was synthesized by electrostatically coating calcium alginate onto diethylenetriamine (dien)-silica gel. Copper ion adsorption tests by a batch method showed that CaAD exhibited a higher adsorption rate compared with other biosorbents despite its low maximum adsorption capacity. Next, CaAD was packed into a 1 mL microcolumn, which was connected to a flow analytical system equipped with an FAAS instrument. The flow system quantitatively adsorbed heavy metals and enriched their concentrations. This quantitative adsorption was achieved for pH 3–4 solutions containing 1.0 × 10{sup −6} M of heavy metal ions at a flow rate of 5.0 mL min{sup −1}. Furthermore, the metal ions were successfully desorbed from CaAD at low nitric acid concentrations (0.05–0.15 M) than from the polyaminecarboxylic acid chelating resin (Chelex 100). Therefore, CaAD may be considered as a biosorbent that quickly adsorbs and easily desorbs analyte metal ions. In addition, the flow system enhanced the concentrations of heavy metals such as Cu{sup 2+}, Zn{sup 2+}, and Pb{sup 2+} by 50-fold. This new enrichment system successfully performed the separation and determination of Cu{sup 2+} (5.0 × 10{sup −8} M) and Zn{sup 2+} (5.7 × 10{sup −8} M) in a river water sample and Pb{sup 2+} (3.8 × 10{sup −9} M) in a ground water sample.

  13. Evaluation of cadmium, lead, copper, iron and zinc in Turkish dietary vegetable oils and olives using electrothermal and flame atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    Acar, Orhan

    2012-10-01

    Full Text Available The Cd, Pb, Cu, Fe and Zn contents of some edible vegetable oils (soybean, sunflower, flower, nut, corn and olive and of olives (olive-1, black, green, black crushed with seeds and green crushed with seeds were determined and evaluated by an electrothermal atomic absorption spectrometer (ETAAS using an Sc + Ir + NH4H2PO4 chemical modifier mixture and flame atomic absorption spectrometer (FAAS after microwave digestion. The pyrolysis and atomization temperatures of Cd, Pb and Cu in sample solutions with and without the modifier mixture were investigated. The limits of detection (LOD for analytes found are 0.1, 0.6, 0.9, 15.0 and 12.0 μg L–1 for Cd, Cu, Pb, Fe and Zn, respectively. The accuracy of the procedure proposed was confirmed by analyzing bovine liver 1577b standard reference material (SRM and a spiked sample solution. The results of the analytes found were compared with certified and added values. The relative standard deviations of the analytes found were lower than 7% and the percent of recoveries obtained ranges from 96 to 101%. The Sc + Ir + NH4H2PO4 mixture proposed was applied for the determination of Cd, Pb and Cu in oils and olives. The results of analytes found in the samples were compared with international and national food quality guidelines as well as with literature values.

    Se han determinado los metales Cd, Cu, Pb, Fe y Zn en aceites vegetales comestibles (soja, girasol, flores, nueces, maíz y aceite de oliva y aceitunas (aceitunas-1, negra, verde, negra machacadas con semillas y verde machacadas con semillas mediante espectrometría de absorción atómica electrotérmica (ETAAS utilizando como modificador químico la mezcla Sc + Ir + NH4H2PO4 y mediante espectrometría de absorción atómica de llama (FAAS tras digestión con microondas. Se estudiaron las temperaturas de pirólisis y atomización para Cd

  14. Pressure broadening of atomic oxygen two-photon absorption laser induced fluorescence

    Science.gov (United States)

    Marinov, Daniil; Drag, Cyril; Blondel, Christophe; Guaitella, Olivier; Golda, Judith; Klarenaar, Bart; Engeln, Richard; Schulz-von der Gathen, Volker; Booth, Jean-Paul

    2016-12-01

    Atomic oxygen, considered to be a determining reactant in plasma applications at ambient pressure, is routinely detected by two-photon absorption laser induced fluorescence (TALIF). Here, pressure broadening of the (2p 4 3 P 2  →  3p 3 P J=0,1,2) two-photon transition in oxygen atoms was investigated using a high-resolution TALIF technique in normal and Doppler-free configurations. The pressure broadening coefficients determined were {γ{{\\text{O}2}}}   =  0.40  ±  0.08  cm-1/bar for oxygen molecules and {γ\\text{He}}   =  0.46  ±  0.03 cm-1/bar for helium atoms. These correspond to pressure broadening rate constants k\\text{PB}{{\\text{O}2}}   =  9 · 10-9 cm3 s-1 and k\\text{PB}\\text{He}   =  4 · 10-9 cm3 s-1, respectively. The well-known quenching rate constants of O(3p 3 P J ) by O2 and He are at least one order of magnitude smaller, which signifies that non-quenching collisions constitute the main line-broadening mechanism. In addition to providing new insights into collisional processes of oxygen atoms in electronically excited 3p 3 P J state, reported pressure broadening parameters are important for quantification of oxygen TALIF line profiles when both collisional and Doppler broadening mechanisms are important. Thus, the Doppler component (and hence the temperature of oxygen atoms) can be accurately determined from high resolution TALIF measurements in a broad range of conditions.

  15. Atomic oxygen adsorption and absorption on Rh(111) and Ag(111)

    Science.gov (United States)

    Derouin, Jonathan D.

    A central question in the field of heterogeneous catalysis is how surface structure and subsurface species influence catalytic behavior. One key to answering that question is determining which surface structures and subsurface species are present under catalytically relevant conditions. This dissertation presents results of Auger electron spectroscopy, low energy electron diffraction, temperature programmed desorption, and scanning tunneling microscopy experiments on oxidized Rh(111) and Ag(111) crystals. Exposing Rh(111) to O2 produced a predominately (2 x 1) adlayer, but even after extended dosing, (2 x 2) domains were also present. Exposing Rh(111) to atomic oxygen yielded O coverages greater than 0.5 ML and (1 x 1) domains were observed to form along terrace step edges. However, (2 x 1) and (2 x 2) domains were still present. Atomic oxygen was used to oxidize Ag(111) in order to study the effect of sample temperature as well as oxygen flux and energy. When atomic oxygen was generated using a lower temperature thermal cracker, a variety of previously reported surface structures were observed. When O was generated using a higher filament temperature, the surface became highly corrugated, layers of Ag 2O appeared to form, and little subsurface oxygen was observed. To investigate the role of sample temperature, the Ag(111) sample was held at various temperatures while being exposed to atomic oxygen. For short doses, sample temperature had minimal effect on surface reconstruction. For longer doses, changes in sample temperature in the range of 490 K to 525 K had a substantial impact on surface reconstruction and subsurface oxygen absorption. Higher temperature dosing yielded the same surface structures which were observed after short doses. Lower temperature dosing with atomic oxygen resulted in subsurface oxygen formation and new structures which covered the surface. The results indicate the rich complexity of oxygen/transition metal interactions and illustrate how

  16. Rhodium as permanent modifier for atomization of lead from biological fluids using tungsten filament electrothermal atomic absorption spectrometry

    Science.gov (United States)

    Zhou, Ying; Parsons, Patrick J.; Aldous, Kenneth M.; Brockman, Paul; Slavin, Walter

    2002-04-01

    Rhodium (Rh) was investigated as a permanent modifier for the atomization of Pb from biological fluids in W-filament atomic absorption spectrometry (AAS). Heating the W-filament with a Rh solution provided a protective coating for subsequent determinations of Pb in blood and urine matrices. The W-filament AAS instrumentation used was based on a prototype design that utilized self-reversal background correction scheme and peak area measurements. We found that Rh not only stabilized Pb during the pyrolysis step, but also facilitated the removal of carbonaceous residues during the cleaning step, requiring much less power than with phosphate modifier. Thus, the filament lifetime was greatly extended to over 300 firings. Periodic reconditioning with Rh was necessary every 30 firings or so. Conditioning the filament with Rh also permitted direct calibration using simple aqueous Pb standards. The method detection limit for blood Pb was approximately 1.5 μg dl -1, similar to that reported previously. Potential interferences from concomitants such as Na, K, Ca and Mg were evaluated. Accuracy was verified using lead reference materials from the National Institute of Standards and Technology and the New York State Department of Health. Blood lead results below 40 μg dl -1 were within ±1 μg dl -1 of certified values, and within ±10% above 40 μg dl -1; within-run precision was ±10% or better. Additional validation was reported using proficiency test materials and human blood specimens. All blood lead results were within the acceptable limits established by regulatory authorities in the US. When measuring Pb in urine, sensitivity was reduced and matrix-matched calibration became necessary. The method of detection limit was 27 μg l -1 for urine Pb. Urine lead results were also validated using an acceptable range comparable to that established for blood lead by US regulatory agencies.

  17. Effect of Atomic Coherence on Absorption in Four-level Systems: an Analytical study

    CERN Document Server

    Sandhya, S N

    2006-01-01

    Absorption profile of a four-level ladder atomic system interacting with three driving fields is studied perturbatively and analytical results are presented. Numerical results where the driving field strengths are treated upto all orders are presented. The absorption features is studied in two regimes, i) the weak middle transition coupling, i.e. $\\Omega_2 \\Omega_{1,3}$ and ii) the strong middle transition coupling $\\Omega_2 \\Omega_{1,3}$. In case i), it is shown that the ground state absorption and the saturation characteristics of the population of level 2 reveal deviation due to the presence of upper level couplings. In particular, the saturation curve for the population of level 2 shows a dip for $\\Omega_1 = \\Omega_3$. While the populations of levels 3 and 4 show a maxima when this resonance condition is satisfied. Thus the resonance condition provides a criterion for maximally populating the upper levels. A second order perturbation calculation reveals the nature of this minima (maxima). In the second ca...

  18. Speciation of four selenium compounds using high performance liquid chromatography with on-line detection by inductively coupled plasma mass spectrometry or flame atomic absorption spectrometry

    DEFF Research Database (Denmark)

    Pedersen, Gitte Alsing; Larsen, Erik Huusfeldt

    1997-01-01

    spectrometry (ICP-MS). The signal-to-noise ratio of the FAAS detector was optimized using a hydrogen-argon entrained-air flame and a slotted-tube atom trap (STAT) in the flame. The limit of detection (3 sigma) achieved by the HPLC-FAAS system was 1 mg L-1 of selenium (100 mu L injections) for each of the four......An analytical method for the speciation of selenomethionine, selenocystine, selenite and selenate by high performance liquid chromatography (HPLC) with atomic spectrometric detection is presented. An organic polymeric strong anion exchange column was used as the stationary phase in combination...... of 1300 W. The limit of detection achieved under these conditions was 1 mu g L-1 (100 mu L injections). The HPLC-ICP-MS system was used for selenium speciation of selenite and selenate in aqueous solutions during a BCR certification exercise and for selenium speciation in the certified reference material...

  19. Slurry sampling techniques for the determination of lead in Bangladeshi fish samples by electrothermal atomic absorption spectrometry with a metal tube atomizer.

    Science.gov (United States)

    Rahman, Mohammad Arifur; Kaneco, Satoshi; Suzuki, Tohru; Katsumata, Hideyuki; Ohta, Kiyohisa

    2005-05-01

    Ultrasonic slurry sampling electrothermal atomic absorption spectrometry with a metal tube atomizer has been applied to the determination of lead in Bangladeshi fish samples. The slurry sampling conditions, such as slurry stabilizing agent, slurry concentration, pyrolysis temperature for the slurried fish samples, particle size and ultrasonic agitation time, were optimized for electrothermal atomic absorption spectrometry with the Mo tube atomizer. Thiourea was used as the chemical modifier for the interference of matrix elements. The detection limit was 53 fg (3S/N). The determined amount of lead in Bangladeshi fish samples was consistent with those measured in the dissolved acid-digested samples. The advantages of the proposed methods are easy calibration, simplicity, low cost and rapid analysis.

  20. Slurry sampling graphite furnace atomic absorption spectrometry: determination of trace metals in mineral coal.

    Science.gov (United States)

    Silva, M M; Goreti, M; Vale, R; Caramão, E B

    1999-12-06

    A procedure for lead, cadmium and copper determination in coal samples based on slurry sampling using an atomic absorption spectrometer equipped with a transversely heated graphite tube atomizer is proposed. The slurries were prepared by weighing the samples directly into autosampler cups (5-30 mg) and adding a 1.5 ml aliquot of a diluent mixture of 5% v/v HNO(3), 0.05% Triton X-100 and 10% ethanol. The slurry was homogenized by manual stirring before measurement. Slurry homogenization using ultrasonic agitation was also investigated for comparison. The effect of particle size and the use of different diluent compositions on the slurry preparation were investigated. The temperature programmes were optimized on the basis of pyrolysis and atomization curves. Absorbance characteristics with and without the addition of a palladium-magnesium modifier were compared. The use of 0.05% m/v Pd and 0.03% m/v Mg was found satisfactory for stabilizing Cd and Pb. The calibration was performed with aqueous standards. In addition, a conventional acid digestion procedure was applied to verify the efficiency of the slurry sampling. Better recoveries of the analytes were obtained when the particle size was reduced to <37 mum. Several certified coal reference materials (BCR Nos. 40, 180, and 181) were analyzed, and good agreement was obtained between the results from the proposed slurry sampling method and the certificate values.

  1. Minimizing chemical interference errors for the determination of lithium in brines by flame atomic absorption spectroscopy analysis

    Institute of Scientific and Technical Information of China (English)

    WEN Xianming; MA Peihua; ZHU Geqin; WU Zhiming

    2006-01-01

    Chemical interferences (ionization and oxide/hydroxide formation) on the atomic absorbance signal of lithium in FAAS analysis of brine samples are elaborated in this article. It is suggested that inadequate or overaddition of deionization buffers can lead to loss of sensitivities under particular operating conditions. In the analysis of brine samples, signal enhancing and oxide/hydroxide formation inducing signal reduction resulting from overaddition of deionization buffers can be seen with varying amounts of chemical buffers. Based on experimental results, the authors have arrived at the op timized operating conditions for the detection of lithium, under which both ionization and stable compound formation can be suppressed. This is a simplified and quick method with adequate accuracy and precision for the determination of lithium in routine brine samples from chemical plants or R&D laboratories, which contain comparable amounts of lithium with some other components.

  2. Silicic acid (Si(OH)(4)) is a significant influence upon the atomic absorption signal of aluminium measured by graphite furnace atomic absorption spectrometry (GFAAS).

    Science.gov (United States)

    Schneider, C; Exley, C

    2001-11-01

    We have identified silicic acid (Si(OH)(4)) as an important modifier of the absorbance signal of aluminium measured by graphite furnace atomic absorption spectrometry (GFAAS). The presence of Si(OH)(4) enhanced the signal by as much as 50%. The extent of the enhancement was dependent upon both [Al] and [Si(OH)(4)] and was maximal when [Al] or =0.50 mmol dm(-3). The enhancement of the Al absorbance signal was not linearly related to [Si(OH)(4)] and the effect was, generally, saturated, for all [Al] tested, at [Si(OH)(4)]> or =0.50 mmol dm(-3). Si(OH)(4) was significantly more effective in enhancing the Al absorbance signal than Mg(NO(3))(2). However, the co-occurrence of 10 mmol dm(-3) Mg(NO(3))(2) and 2 mmol dm(-3) Si(OH)(4) in samples abolished the enhancement due to Si(OH)(4). The presence of Si(OH)(4) in samples could result in an overestimation of the Al content of those samples by as much as 50%. Errors in the measurement of Al in samples containing Si(OH)(4) could be prevented using matrix-matched calibration standards. Our observation could have serious implications for the determination of Al in aqueous samples of both geochemical and biological interest. It may also point towards the application of Si(OH)(4) as a novel and effective matrix modifier in the determination of Al by GFAAS since the inclusion of Si(OH)(4) in standards and samples improved the limit of detection of Al from ca 8 nmol dm(-3) to 3 nmol dm(-3).

  3. In situ emulsification microextraction using a dicationic ionic liquid followed by magnetic assisted physisorption for determination of lead prior to micro-sampling flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Shokri, Masood; Beiraghi, Asadollah [Faculty of Chemistry, Kharazmi University, Tehran (Iran, Islamic Republic of); Seidi, Shahram, E-mail: s.seidi@kntu.ac.ir [Department of Analytical Chemistry, Faculty of Chemistry, K.N. Toosi University of Technology, Tehran (Iran, Islamic Republic of)

    2015-08-19

    For the first time, a simple and efficient in situ emulsification microextraction method using a dicationic ionic liquid followed by magnetic assisted physisorption was presented to determine trace amounts of lead. In this method, 400 μL of 1.0 mol L{sup −1} lithium bis (trifluoromethylsulfonyl) imide aqueous solution, Li[NTf{sub 2}], was added into the sample solution containing 100 μL of 1.0 mol L{sup −1} 1,3-(propyl-1,3-diyl) bis (3-methylimidazolium) chloride, [pbmim]Cl{sub 2}, to form a water immiscible ionic liquid, [pbmim][NTf{sub 2}]{sub 2}. This new in situ formed dicationic ionic liquid was applied as the acceptor phase to extract the lead-ammonium pyrrolidinedithiocarbamate (Pb-APDC) complexes from the sample solution. Subsequently, 30 mg of Fe{sub 3}O{sub 4} magnetic nanoparticles (MNPs) were added into the sample solution to collect the fine droplets of [pbmim][NTf{sub 2}]{sub 2}, physisorptively. Finally, MNPs were eluted by acetonitrile, separated by an external magnetic field and the obtained eluent was subjected to micro-sampling flame atomic absorption spectrometry (FAAS) for further analysis. Comparing with other microextraction methods, no special devices and centrifugation step are required. Parameters influencing the extraction efficiency such as extraction time, pH, concentration of chelating agent, amount of MNPs and coexisting interferences were studied. Under the optimized conditions, this method showed high extraction recovery of 93% with low LOD of 0.7 μg L{sup −1}. Good linearity was obtained in the range of 2.5–150 μg L{sup −1} with determination coefficient (r{sup 2}) of 0.9921. Relative standard deviation (RSD%) for seven repeated measurements at the concentration of 10 μg L{sup −1} was 4.1%. Finally, this method was successfully applied for determination of lead in some water and plant samples. - Highlights: • A dicationic ionic liquid was used as the extraction solvent, for the first time. • A

  4. Preconcentration and Determination of Chromium Species Using Octadecyl Silica Membrane Disks and Flame Atomic Absorption Spectrometry

    Institute of Scientific and Technical Information of China (English)

    MOGHIMI Ali; SABER-TEHRANI Mohammad; WAQIF-HUSAIN Syed; MOHAMMADHOSSEINI Majid

    2007-01-01

    A novel and selective method for the fast determination of trace amounts of chromium species in water samples has been developed.The procedure is based on the selective formation of chromium diethyldithiocarbamate complexes at different pH in the presence of Mn(Ⅱ) as an enhancement agent of chromium signals followed by elutionwith organic eluents and determination by atomic flame absorption spectrometry.The maximum capacity of the employed disks was found to be (3964±3) μg and (376±2) μg for Cr(Ⅲ) and Cr(Ⅵ),respectively.The detection limit of the proposed method is 49 and 43 ng·L-1 for Cr(Ⅲ) and Cr(Ⅵ),respectively.The proposed method was successfully applied for determination of chromium species Cr(Ⅲ) and Cr(Ⅵ) in different water samples.

  5. Determination of cyanide by a flow injection analysis-atomic absorption spectrometric method.

    Science.gov (United States)

    López Gómez, A V; Martínez Calatayud, J

    1998-10-01

    A new flow injection analysis (FIA) procedure is proposed for the indirect atomic absorption spectrometric determination of cyanide. The FIA manifold is based on the insertion of the sample into a distilled water carrier, then the sample flows through a solid-phase reactor filled with silver iodide entrapped in polymeric resin beads. The calibration graph is linear over the range 0.2-6.0 mg l-1 of cyanide (correlation coefficient 0.9974), the detection limit is 0.1 mg l-1, the sample throughput is 193 h-1 and the RSD is 0.8%. The method is simple, quick and more selective than other published FIA procedures. The reproducibility obtained by using different solid-phase reactors and solutions is in the range 2.2-3.1% (RSD). The method was applied to the determination of cyanide in commercial samples such as pharmaceutical formulations and industrial electrolytic baths.

  6. Determination of palladium by graphite furnace atomic absorption spectroscopy without matrix matching.

    Science.gov (United States)

    Jia, X; Wang, T; Wu, J

    2001-05-30

    A graphite furnace atomic absorption spectroscopy method for the analysis of the palladium (Pd) content in bulk pharmaceutical drug substances and their intermediates prepared in aqueous solutions is extended to samples prepared in acetonitrile (ACN) and ACN-water mixtures as well to samples prepared in dimethyl sulfoxide (DMSO) and DMSO-water mixtures. The Pd content in samples solubilized in these solvents can be accurately determined with calibration established with standards prepared in aqueous solutions without matrix matching or using the method of standard additions. The validity of this method is demonstrated by spike recovery studies and by the agreement with results for the same samples prepared in these solvents, in concentrated nitric acid, and prepared by a microwave digestion system.

  7. Determination of calcium, magnesium and zinc in unused lubricating oils by atomic absorption spectroscopy.

    Science.gov (United States)

    Udoh, A P

    1995-12-01

    Varying concentrations of lanthanum and strontium were added to solutions of ashed unused lubricating oils for the determination of calcium, magnesium and zinc content using flame atomic absorption spectrophotometry. At least 3000 mug g(-1) of lanthanum or strontium was required to completely overcome the interference of the phosphate ion, PO(3-)(4), and give peak values for calcium. The presence of lanthanum or strontium did not cause an appreciable increase in the amount of magnesium and zinc obtained from the analyses. The method is fast and reproducible, and the coefficients of variation calculated for the elements using one of the samples were 1.6% for calcium, 3.5% for magnesium and 0.2% for zinc. Results obtained by this method were better than those obtained by other methods for the same samples.

  8. Application of atomic absorption spectroscopy for detection of multimetal traces in low-voltage electrical marks.

    Science.gov (United States)

    Jakubeniene, Marija; Zakaras, Algirdas; Minkuviene, Zita Nijole; Benoshys, Alvydas

    2006-08-10

    Application of atomic absorption spectroscopy to detect multimetal traces in injured skin is a promising tool for investigation of fatalities caused by electrocution. The present paper is aimed at testing the reliability of this method for metal traces detection in electric current marks and is focused on study of peculiarities of metal penetration into the skin exposed to a current impact. Bare aluminum wire, tin-lead coated copper multistrand wire, and zinc-plated steel rope were used to make electrical marks on pig skin. It is demonstrated that amount of copper, zinc, lead, and iron may serve as statistically reliable indicators for the type of wire, which caused the electrical mark, in spite of the background content of these metals in the skin without injury. Different penetration rates for different metals contained in the wire inflicting an electrical mark were observed.

  9. Preconcentration of Vanadium(Ⅴ) on Crosslinked Chitosan and Determination by Graphite Furnace Atomic Absorption Spectrometry

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A new method is proposed for the preconcentration of vanadium(Ⅴ) with crosslinked chitosan (CCTS) and determination by graphite furnace atomic absorption spectrometry (GFAAS). The adsorption rate of vanadium(Ⅴ) by CCTS was 97% at pH 4.0, and vanadium(Ⅴ) was eluted from crosslinked chitosan with 2 mL 2.0 mol*L-1 chlorhydric acid and determined by GFAAS. The detection limit (3σ,n=7) for vanadium(Ⅴ) was 4.8×1 0-12g and the relative standard deviation (R.S.D) at concentration level of 2.6 μg*L-1 is less than 3.6%. The method shows a good selectivity and high sensitivity, and it was applied to determination of vanadium(Ⅴ) in oyster and water samples. The analytic recoveries are (97±5)%.

  10. Removal of iron interferences by solvent extraction for geochemical analysis by atomic-absorption spectrophotometry

    Science.gov (United States)

    Zhou, L.; Chao, T.T.; Sanzolone, R.F.

    1985-01-01

    Iron is a common interferent in the determination of many elements in geochemical samples. Two approaches for its removal have been taken. The first involves removal of iron by extraction with methyl isobutyl ketone (MIBK) from hydrochloric acid medium, leaving the analytes in the aqueous phase. The second consists of reduction of iron(III) to iron(II) by ascorbic acid to minimize its extraction into MIBK, so that the analytes may be isolated by extraction. Elements of interest can then be determined using the aqueous solution or the organic extract, as appropriate. Operating factors such as the concentration of hydrochloric acid, amounts of iron present, number of extractions, the presence or absence of a salting-out agent, and the optimum ratio of ascorbic acid to iron have been determined. These factors have general applications in geochemical analysis by atomic-absorption spectrophotometry. ?? 1985.

  11. ANALYSIS OF VARIOUS METAL IONS IN SOME MEDICINAL PLANTS USING ATOMIC ABSORPTION SPECTROPHOTOMETER

    Directory of Open Access Journals (Sweden)

    Y.L. Ramachandra*, C. Ashajyothi and Padmalatha S. Rai

    2012-07-01

    Full Text Available Metal ions such as iron , lead, copper, nickel, cadmium , chromium and zinc were investigated in medicinally important plants Alstonia scholaris, Tabernaemontana coronariae, Asparagus racemosus, Mimosa pudica, Leucas aspera and Adhatoda vasica applying atomic absorption spectrophotometer techniques. The purpose of this study was to standardize various metal ion Contamination in indigenous medicinal plants. Maximum concentration of lead was present in Leucas aspera and Adhatoda vasica followed by Alstonia scholaris, Tabernaemontana coronariae and Asparagus racemosus. The concentration of lead in Mimosa pudica was below the detectable level. The maximum concentration of zinc was detected in Adhatoda vasica followed by Leucas aspera, Asparagus racemosus, Tabernaemontana coronariae, Alstonia scholaris and Mimosa pudica. The concentration of Cadmium, nickel and chromium was below the detectable level.

  12. Neutron activation analysis and atomic absorption spectrophotometry for the analysis of fresh, pasteurised and powder milk

    Energy Technology Data Exchange (ETDEWEB)

    Wasim, M.; Rehman, S.; Arif, M.; Fatima, I.; Zaidi, J.H. [Pakistan Inst. of Nuclear Science and Technology, Islamabad (Pakistan). Chemistry Div.

    2012-07-01

    This study shows the application of semi-absolute k{sub 0} instrumental neutron activation analysis (k{sub 0}-INAA), epithermal neutron activation analysis (ENAA) and atomic absorption spectrophotometry (AAS) for the determination of 21 elements (Br, Ca, Cl, Co, Cr, Cs, Cu, Fe, Hf, I, K, Mg, Mn, Na, Ni, P, Pb, Rb, Sc Sr, and Zn) in different types of milk samples. The ENAA was required for the determination of iodine, AAS for Cu, Ni and Pb and the rest of the elements were measured by k{sub 0}-INAA. Thirteen elements (Br, Ca, Cl, Cs, Cu, Fe, K, Mg, Na, P, Rb, Sr and Zn) were identified in all milk samples. Ni was detected in eleven and Pb in two samples. Concentrations of most of the elements were within the ranges of the world reported data. The data was further explored by principal component analysis to find relationships between samples and elements. (orig.)

  13. DETERMINATION OF NICKLE CONTENTS IN SELECTED VANASPATI GHEE THROUGH ATOMIC ABSORPTION SPECTROPHOTOMETER

    Directory of Open Access Journals (Sweden)

    Waqas Ahmad

    2014-12-01

    Full Text Available To convert vegetable edible oils into vanaspati ghee, nickel is used as a catalyst in the hydrogenation process. A simple and fast method for the trace level determination of nickel in ghee is reported. In this different methods were applied for the extraction of residual nickel from ghee samples. Using toluene, as organic solvents, an acid mixture was used for the extraction of nickel. Extracted nickel was quantified with atomic absorption. Among the organic solvents, toluene proved to be the best solvent mediating a 95% extraction of nickel from ghee samples. Nickel was extracted and determined in ten different brands of ghee and in all samples its amount was well above the permissible limit of WHO (0.2 μg/g. Other metals like lead, zinc, copper, and cadmium were also determined and their concentrations were found to be much below the WHO permissible limits.

  14. [Determination of inorganic elements in different parts of Sonchus oleraceus L by flame atomic absorption spectrometry].

    Science.gov (United States)

    Wang, Nai-Xing; Cui, Xue-Gui; Du, Ai-Qin; Mao, Hong-Zhi

    2007-06-01

    Flame atomic absorption spectrometry with air-acetylene flame was used for the determination of inorganic metal elements in different parts ( flower, leaf, stem and root) of Sonchus oleraceus L. The contents of Ca, Mg, K, Na, Fe, Mn, Cu, Zn, Cr, Co, Ni, Pb and Cd in the flower, leaf, stem and root of Sonchus oleraceus L were compared. The order from high to low of the additive weight (microg x g(-1)) for the 13 kinds of metal elements is as follows: leaf (77 213.72) > flower (47 927.15) > stem(42 280.99) > root (28 131.18). From the experimental results it was found that there were considerable differences in the contents of the metal elements in different parts, and there were richer contents of Fe, Zn, Mn and Cu in root and flower, which are necessary to human health, than in other parts.

  15. Determination of sodium in foods by flame atomic absorption spectrometry after microwave digestion: NMKL interlaboratory study.

    Science.gov (United States)

    Julshamn, Kaare; Lea, Per; Norli, Hilde Skaar

    2005-01-01

    Nine laboratories participated in an interlaboratory method performance (collaborative) study of a method for the determination of sodium in foods by flame atomic absorption spectrometry after wet digestion, using a microwave oven technique. Before the study, the laboratories were able to practice on samples with defined sodium levels (pretrial test). The method was tested on a total of 6 foods (broccoli, carrot, bread, saithe fillet, pork, and cheese) with sodium concentrations of 1480-8260 mg/kg. The materials were presented to the participants in the study as blind duplicates, and the participants were asked to perform single determinations for each sample. The repeatability relative standard deviations (RSDr) for sodium ranged from 1.9 to 6.5%. The reproducibility relative standard deviations (RSDR) ranged from 4.2 to 6.9%. The HorRat values ranged from 0.9 to 1.6.

  16. Atomic Absorption Spectrometric Method for Estimation of Diclofenac sodium and Mefenamic acid in Pharmaceutical Formulations

    Directory of Open Access Journals (Sweden)

    Sunil Jawla

    2010-01-01

    Full Text Available Diclofenac sodium and Mefenamic acid have been quantified in tablet dosage form by atomic absorption spectrometry (AAS. These methods are based on formation of the metal complexes of Diclofenac sodium and Mefenamic acid with cupric chloride and cobaltous chloride. The first method is based on reaction of both the drugs with cupric chloride to give light blue colored metal complexes, which are then extracted with dichloromethane and digested with 0.1 M nitric acid. Both the drugs are indirectly estimated via determination of copper content in the formed complexes by AAS. The second method is based on the formation of pink colored complexes of both the drugs with cobaltous chloride. These metal complexes are extracted with dichloromethane and estimated via determination of cobalt content in the formed complexes after digestion with 0.1 M nitric acid by AAS.

  17. Determination of barium in bottled drinking water by graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Fagioli, F.; Locatelli, C.; Lanciotti, E.; Vallone, G.; Mazzotta, D.; Mugelli, A.

    1988-11-01

    In relation to the wide environmental spread of barium and to its cardiovascular effects, barium levels were determined by graphite furnace atomic absorption spectrometry in 60 different brands of bottled water marketed in Italy. Matrix interferences were investigated in order to evaluate the use of an analytical calibration function rather than the much more time consuming addition technique. The barium content ranged from limit of detection C/sub L/ (7.0 ..mu..g/1) up to 660 ..mu..g/1, the median value being 80 ..mu..g/l, while the recovery tests varied between 90 and 110% and the precision of the method (s/sub yx/) was 2.5%.

  18. Novel analytical reagent for the application of cloud-point preconcentration and flame atomic absorption spectrometric determination of nickel in natural water samples

    Energy Technology Data Exchange (ETDEWEB)

    Suvardhan, K. [Environmental Monitoring Laboratory, Department of Chemistry, S.V. University, AP (India); Rekha, D. [Environmental Monitoring Laboratory, Department of Chemistry, S.V. University, AP (India); Kumar, K. Suresh [Environmental Monitoring Laboratory, Department of Chemistry, S.V. University, AP (India); Prasad, P. Reddy [Environmental Monitoring Laboratory, Department of Chemistry, S.V. University, AP (India); Kumar, J. Dilip [Environmental Monitoring Laboratory, Department of Chemistry, S.V. University, AP (India); Jayaraj, B. [Department of Mathematics, S.V. University, Tirupati 517502, AP (India); Chiranjeevi, P. [Environmental Monitoring Laboratory, Department of Chemistry, S.V. University, AP (India)]. E-mail: chiranjeevipattium@gmail.com

    2007-06-01

    Cloud-point extraction was applied as a preconcentration of nickel after formation of complex with newly synthesized N-quino[8,7-b]azin-5-yl-2,3,5,6,8,9,11,12octahydrobenzo[b][1,4,7,10,13] pentaoxacyclopentadecin-15-yl-methanimine, and later determined by flame atomic absorption spectrometry (FAAS) using octyl phenoxy polyethoxy ethanol (Triton X-114) as surfactant. Nickel was complexed with N-quino[8,7-b]azin-5-yl-2,3,5,6,8,9,11,12 octahydrobenzo[b][1,4,7,10,13]pentaoxacyclopentadecin-15-yl-methanimine in an aqueous phase and was kept for 15 min in a thermo-stated bath at 40 deg. C. Separation of the two phases was accomplished by centrifugation for 15 min at 4000 rpm. The chemical variables affecting the cloud-point extraction were evaluated, optimized and successfully applied to the nickel determination in various water samples. Under the optimized conditions, the preconcentration system of 100 ml sample permitted an enhancement factor of 50-fold. The detailed study of various interferences made the method more selective. The detection limits obtained under optimal condition was 0.042 ng ml{sup -1}. The extraction efficiency was investigated at different nickel concentrations (20-80 ng ml{sup -1}) and good recoveries (99.05-99.93%) were obtained using present method. The proposed method has been applied successfully for the determination of nickel in various water samples and compared with reported method in terms of Student's t-test and variance ratio f-test which indicate the significance of present method over reported and spectrophotometric methods at 95% confidence 0011lev.

  19. Cloud point extraction for determination of lead in blood samples of children, using different ligands prior to analysis by flame atomic absorption spectrometry: A multivariate study

    Energy Technology Data Exchange (ETDEWEB)

    Shah, Faheem, E-mail: shah_ceac@yahoo.com [National Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan); Kazi, Tasneem Gul, E-mail: tgkazi@yahoo.com [National Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan); Afridi, Hassan Imran, E-mail: hassanimranafridi@yahoo.com [National Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan); Naeemullah, E-mail: khannaeemullah@ymail.com [National Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan); Arain, Muhammad Balal, E-mail: bilal_ku2004@yahoo.com [Department of Chemistry, University of Science and Technology, Bannu, KPK (Pakistan); Baig, Jameel Ahmed, E-mail: jab_mughal@yahoo.com [National Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan)

    2011-09-15

    Highlights: {yields} Trace levels of lead in blood samples of healthy children and with different kidney disorders {yields} Pre-concentration of Pb{sup +2} in acid digested blood samples after chelating with two complexing reagents. {yields} Multivariate technique was used for screening of significant factors that influence the CPE of Pb{sup +2} {yields} The level of Pb{sup +2} in diseased children was significantly higher than referents of same age group. - Abstract: The phase-separation phenomenon of non-ionic surfactants occurring in aqueous solution was used for the extraction of lead (Pb{sup 2+}) from digested blood samples after simultaneous complexation with ammonium pyrrolidinedithiocarbamate (APDC) and diethyldithiocarbamate (DDTC) separately. The complexed analyte was quantitatively extracted with octylphenoxypolyethoxyethanol (Triton X-114). The multivariate strategy was applied to estimate the optimum values of experimental factors. Acidic ethanol was added to the surfactant-rich phase prior to its analysis by flame atomic absorption spectrometer (FAAS). The detection limit value of Pb{sup 2+} for the preconcentration of 10 mL of acid digested blood sample was 1.14 {mu}g L{sup -1}. The accuracy of the proposed methods was assessed by analyzing certified reference material (whole blood). Under the optimized conditions of both CPE methods, 10 mL of Pb{sup 2+} standards (10 {mu}g L{sup -1}) complexed with APDC and DDTC, permitted the enhancement factors of 56 and 42, respectively. The proposed method was used for determination of Pb{sup 2+} in blood samples of children with kidney disorders and healthy controls.

  20. Preconcentration and determination of vanadium and molybdenum in milk, vegetables and foodstuffs by ultrasonic-thermostatic-assisted cloud point extraction coupled to flame atomic absorption spectrometry.

    Science.gov (United States)

    Gürkan, Ramazan; Korkmaz, Sema; Altunay, Nail

    2016-08-01

    A new ultrasonic-thermostatic-assisted cloud point extraction procedure (UTA-CPE) was developed for preconcentration at the trace levels of vanadium (V) and molybdenum (Mo) in milk, vegetables and foodstuffs prior to determination via flame atomic absorption spectrometry (FAAS). The method is based on the ion-association of stable anionic oxalate complexes of V(V) and Mo(VI) with [9-(diethylamino)benzo[a]phenoxazin-5-ylidene]azanium; sulfate (Nile blue A) at pH 4.5, and then extraction of the formed ion-association complexes into micellar phase of polyoxyethylene(7.5)nonylphenyl ether (PONPE 7.5). The UTA-CPE is greatly simplified and accelerated compared to traditional cloud point extraction (CPE). The analytical parameters optimized are solution pH, the concentrations of complexing reagents (oxalate and Nile blue A), the PONPE 7.5 concentration, electrolyte concentration, sample volume, temperature and ultrasonic power. Under the optimum conditions, the calibration curves for Mo(VI) and V(V) are obtained in the concentration range of 3-340µgL(-1) and 5-250µgL(-1) with high sensitivity enhancement factors (EFs) of 145 and 115, respectively. The limits of detection (LODs) for Mo(VI) and V(V) are 0.86 and 1.55µgL(-1), respectively. The proposed method demonstrated good performances such as relative standard deviations (as RSD %) (≤3.5%) and spiked recoveries (95.7-102.3%). The accuracy of the method was assessed by analysis of two standard reference materials (SRMs) and recoveries of spiked solutions. The method was successfully applied into the determination of trace amounts of Mo(VI) and V(V) in milk, vegetables and foodstuffs with satisfactory results.

  1. Fast determination of trace elements in organic fertilizers using a cup-horn reactor for ultrasound-assisted extraction and fast sequential flame atomic absorption spectrometry.

    Science.gov (United States)

    Teixeira, Leonel Silva; Vieira, Heulla Pereira; Windmöller, Cláudia Carvalhinho; Nascentes, Clésia Cristina

    2014-02-01

    A fast and accurate method based on ultrasound-assisted extraction in a cup-horn sonoreactor was developed to determine the total content of Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn in organic fertilizers by fast sequential flame atomic absorption spectrometry (FS FAAS). Multivariate optimization was used to establish the optimal conditions for the extraction procedure. An aliquot containing approximately 120 mg of the sample was added to a 500 µL volume of an acid mixture (HNO3/HCl/HF, 5:3:3, v/v/v). After a few minutes, 500 µL of deionized water was added and eight samples were simultaneously sonicated for 10 min at 50% amplitude, allowing a sample throughput of 32 extractions per hour. The performance of the method was evaluated with a certified reference material of sewage sludge (CRM 029). The precision, expressed as the relative standard deviation, ranged from 0.58% to 5.6%. The recoveries of analytes were found to 100%, 109%, 96%, 92%, 101%, 104% and 102% for Cd, Cr, Cu, Mn, Ni, Pb and Zn, respectively. The linearity, limit of detection and limit of quantification were calculated and the values obtained were adequate for the quality control of organic fertilizers. The method was applied to the analysis of several commercial organic fertilizers and organic wastes used as fertilizers, and the results were compared with those obtained using the microwave digestion procedure. A good agreement was found between the results obtained by microwave and ultrasound procedures with recoveries ranging from 80.4% to 117%. Two organic waste samples were not in accordance with the Brazilian legislation regarding the acceptable levels of contaminants.

  2. Simultaneous determination of antimony and boron in beverage and dairy products by flame atomic absorption spectrometry after separation and pre-concentration by cloud-point extraction.

    Science.gov (United States)

    Altunay, Nail; Gürkan, Ramazan

    2016-01-01

    A new cloud-point extraction (CPE) method was developed for the pre-concentration and simultaneous determination of Sb(III) and B(III) by flame atomic absorption spectrometry (FAAS). The method was based on complexation of Sb(III) and B(III) with azomethine-H in the presence of cetylpyridinium chloride (CPC) as a signal-enhancing agent, and then extraction into the micellar phase of Triton X-114. Under optimised conditions, linear calibration was obtained for Sb(III) and B(III) in the concentration ranges of 0.5-180 and 2.5-600 μg l(-1) with LODs of 0.15 and 0.75 μg l(-1), respectively. Relative standard deviations (RSDs) (25 and 100 μg l(-1) of Sb(III) and B(III), n = 6) were in a range of 2.1-3.8% and 1.9-2.3%, respectively. Recoveries of spiked samples of Sb(III) and B(III) were in the range of 98-103% and 99-102%, respectively. Measured values for Sb and B in three standard reference materials were within the 95% confidence limit of the certified values. Also, the method was used for the speciation of inorganic antimony. Sb(III), Sb(V) and total Sb were measured in the presence of excess boron before and after pre-reduction with an acidic mixture of KI-ascorbic acid. The method was successfully applied to the simultaneous determination of total Sb and B in selected beverage and dairy products.

  3. Analysis of Some Trace Metals in Fish Species after Preconcentration with Congo Red on Amberlite XAD-7 Resin by Flame Atomic Absorption Spectrometry

    Directory of Open Access Journals (Sweden)

    Güzin Alpdoğan

    2016-01-01

    Full Text Available A new procedure for separation and preconcentration of trace amounts of Cu(II, Ni(II, Fe(III, Zn(II, Cr(III, Cd(II, and Pb(II in fish samples was proposed. The procedure is based on the adsorption of these metal ions on the column of Amberlite XAD-7 as congo red complexes prior to their determination by flame atomic absorption spectrometry (FAAS. Several factors that can affect the sorption and elution efficiency of the metal ions were investigated and optimized. The sorption was quantitative in the pH range of 6.0–9.0 for Cu(II and Ni(II, 5.5–8.0 for Fe(III, 6.0–8.5 for Zn(II and Cd(II, and 7.0–8.5 for Cr(III and Pb(II. The optimum pH for simultaneous retention was 7.5. The sorption capacity of the resin was found to be 0.89, 0.72, 0.82, 0.61, 0.53, 0.84, and 0.78 mg/g for Cu(II, Ni(II, Fe(III, Zn(II, Cr(III, Cd(II, and Pb(II, respectively. The precision of the method was evaluated as the relative standard deviation obtained by analyzing a series of six replicates and below 6% for all seven elements. The validation of the method was performed by the analysis of certified reference materials. The proposed method was successfully applied to separation/preconcentration and determination of these metals in fish samples.

  4. Preparation of modified magnetic nanoparticles as a sorbent for the preconcentration and determination of cadmium ions in food and environmental water samples prior to flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Mirabi, Ali; Dalirandeh, Zeinab [Department of Chemistry, Qaemshahr Branch, Islamic Azad University, Qaemshahr (Iran, Islamic Republic of); Rad, Ali Shokuhi, E-mail: a.shokuhi@qaemshahriau.ac.ir [Department of Chemical Engineering, Qaemshahr Branch, Islamic Azad University, Qaemshahr (Iran, Islamic Republic of)

    2015-05-01

    A new method has been developed for the separation/preconcentration of trace level cadmium ions using diphenyl carbazone/sodium dodecyl sulfate immobilized on magnetic nanoparticle Fe{sub 3}O{sub 4} as a new sorbent SPE and their determination by flame atomic absorption spectrometry (FAAS). Synthesized nanoparticle was characterized by scanning electron microscope (SEM) and transmission electron microscope (TEM). Various influencing parameters on the separation and preconcentration of trace level cadmium ions such as, pH value, amount of nanoparticles, amount of diphenyl carbazone, condition of eluting solution, the effects of matrix ions were examined. The cadmium ions can be eluted from the modified magnetic nanoparticle using 1 mol L{sup −1} HCl as a desorption reagent. The detection limit of this method for cadmium was 3.71 ng ml{sup −1} and the R.S.D. was 0.503% (n=6). The advantages of this new method include rapidity, easy preparation of sorbents and a high concentration factor. The proposed method has been applied to the determination of Cd ions at trace levels in real samples such as, green tea, rice, tobacco, carrot, lettuce, ginseng, spice, tap water, river water, sea water with satisfactory results. - Highlights: • MNPs method is economical, simple, rapid and sensitive for trace analysis of Cd. • High preconcentration factor was obtained easily through this method. • A detection limit at ng mL{sup −1} level was achieved with 100.0 mL of sample. • This method provides good repeatability and extraction efficiency in a short time.

  5. Observations of absorption lines from highly ionized atoms. [of interstellar medium

    Science.gov (United States)

    Jenkins, Edward B.

    1987-01-01

    In the ultraviolet spectra of hot stars, absorption lines can be seen from highly ionized species in the interstellar medium. Observations of these features which have been very influential in revising the perception of the medium's various physical states, are discussed. The pervasiveness of O 6 absorption lines, coupled with complementary observations of a diffuse background in soft X-rays and EUV radiation, shows that there is an extensive network of low density gas (n approx. few x 0.001/cu cm) existing at coronal temperatures log T = 5.3 or 6.3. Shocks created by supernova explosions or mass loss from early-type stars can propagate freely through space and eventually transfer a large amount of energy to the medium. To create the coronal temperatures, the shocks must have velocities in excess of 150 km/sec; shocks at somewhat lower velocity (v = 100 km/sec) can be directly observed in the lines of Si3. Observations of other lines in the ultraviolet, such as Si 4V and C 5, may highlight the widespread presence of energetic UV radiation from very hot, dwarf stars. More advanced techniques in visible and X-ray astronomical spectroscopy may open up for inspection selected lines from atoms in much higher stages of ionization.

  6. Analytical application of 2f-wavelength modulation for isotope selective diode laser graphite furnace atomic absorption spectroscopy.

    Science.gov (United States)

    Wizemann, H D

    2000-01-01

    Experiences in the analytical application of the 2f-wavelength modulation technique for isotope selective atomic absorption spectroscopy in a graphite furnace are reported. Experimental as well as calculated results are presented, mainly for the natural lithium isotopes. Sensitivity, linearity, and (isotope) selectivity are studied by intensity modulation and wavelength modulation. High selectivities can be attained, however, on the cost of detection power. It is shown that the method enables the measurement of lithium isotope ratios larger than 2000 by absorption in a low-pressure graphite tube atomizer.

  7. Determination of mercury in hair: Comparison between gold amalgamation-atomic absorption spectrometry and mass spectrometry.

    Science.gov (United States)

    Domanico, Francesco; Forte, Giovanni; Majorani, Costanza; Senofonte, Oreste; Petrucci, Francesco; Pezzi, Vincenzo; Alimonti, Alessandro

    2016-09-29

    Mercury is a heavy metal that causes serious health problems in exposed subjects. The most toxic form, i.e., methylmercury (MeHg), is mostly excreted through human hair. Numerous analytical methods are available for total Hg analysis in human hair, including cold vapour atomic fluorescence spectrometry (CV-AFS), inductively coupled plasma mass spectrometry (ICP-MS) and thermal decomposition amalgamation atomic absorption spectrometry (TDA-AAS). The aim of the study was to compare the TDA-AAS with the ICP-MS in the Hg quantification in human hair. After the washing procedure to minimize the external contamination, from each hair sample two aliquots were taken; the first was used for direct analysis of Hg by TDA-AAS and the second was digested for Hg determination by the ICP-MS. Results indicated that the two data sets were fully comparable (median; TDA-AAS, 475ngg(-1); ICP-MS, 437ngg(-1)) and were not statistically different (Mann-Whitney test; p=0.44). The two techniques presented results with a good coefficient of correlation (r=0.94) despite different operative ranges and method limits. Both techniques satisfied internal performance requirements and the parameters for method validation resulting sensitive, precise and reliable. Finally, the use of the TDA-AAS can be considered instead of the ICP-MS in hair analysis in order to reduce sample manipulation with minor risk of contamination, less time consuming due to the absence of the digestion step and cheaper analyses.

  8. Direct analysis of silica by means of solid sampling graphite furnace atomic absorption spectrometry

    Science.gov (United States)

    Resano, M.; Mozas, E.; Crespo, C.; Pérez, J.; García-Ruiz, E.; Belarra, M. A.

    2012-05-01

    This paper reports on the use of solid sampling-graphite furnace atomic absorption spectrometry for the direct analysis of synthetic amorphous silica. In particular, determination of hazardous elements such As, Cd, Cr, Cu, Pb and Sb is investigated, as required by regulations of the food industry. The conclusion of the work is that, after proper optimization of the working conditions, paying particular attention to the atomization temperature and the use of proper modifiers (graphite powder, HNO3 or Pd), it is possible to develop suitable procedures that rely on the use of aqueous standard solutions to construct the calibration curves for all the elements investigated. The proposed method shows important benefits for the cost-effective analysis of such difficult samples in routine labs, permitting fast screening of those elements that are very rarely present in this type of sample, but also accurate quantification of those often found, while offering low limits of detection (always below 0.1 mg g- 1) that comply well with legal requirements, and precision levels that are fit for the purpose (approx. 6-9% R.S.D.).

  9. Speciation of mercury in fish samples by flow injection catalytic cold vapour atomic absorption spectrometry.

    Science.gov (United States)

    Zhang, Yanlin; Adeloju, Samuel B

    2012-04-01

    A rapid flow injection catalytic cold vapour atomic absorption spectrometric (FI-CCV-AAS) method is described for speciation and determination of mercury in biological samples. Varying concentrations of NaBH(4) were employed for mercury vapour generation from inorganic and mixture of inorganic and organic (total) Hg. The presence of Fe(3+), Cu(2+) and thiourea had catalytic effect on mercury vapour generation from methylmercury (MeHg) and, when together, Cu(2+) and thiourea had synergistic catalytic effect on the vapour generation. Of the two metal ions, Fe(3+) gave the best sensitivity enhancement, achieving the same sensitivity for MeHg and inorganic Hg(2+). Due to similarity of resulting sensitivity, Hg(2+) was used successfully as a primary standard for quantification of inorganic and total Hg. The catalysis was homogeneous in nature, and it was assumed that the breaking of the C-Hg bond was facilitated by the delocalization of the 5d electron pairs in Hg atom. The extraction of MeHg and inorganic mercury (In-Hg) in fish samples were achieved quantitatively with hydrochloric acid in the presence of thiourea and determined by FI-CCV-AAS. The application of the method to the quantification of mercury species in a fish liver reference material DOLT-4 gave 91.5% and 102.3% recoveries for total and methyl mercury, respectively. The use of flow injection enabled rapid analysis with a sample throughput of 180 h(-1).

  10. Determination of lead in fine particulates by slurry sampling electrothermal atomic absorption spectrometry.

    Science.gov (United States)

    Yu, J C; Ho, K F; Lee, S C

    2001-01-02

    A simple method for determining lead in fine particulates (PM2.5) by using electrothermal atomic absorption spectrometry (ETAAS) has been developed. Particulates collected on Nuclepore filter by using a dichotomous sampler were suspended in diluted nitric acid after ultrasonic agitation. The dislodging efficiency is nearly 100% after agitation for 5 min. In order to study the suspension behavior of PM2.5 in solvents, a Brookhaven ZetaPlus Particle Size Analyzer was used to determine the particle size distribution and suspension behavior of air particulates in the solvent. The pre-digestion and modification effect of nitric acid would be discussed. Palladium was added as a chemical modifier and the temperature program of ETAAS was changed in order to improve the recovery. The slurry was introduced directly into a graphite tube for atomization. The metal content in the sample was determined by the standard addition method. In addition, a conventional acid digestion procedure was applied to verify the efficiency of the slurry sampling method. It offers a quick and efficient alternative method for heavy metal characterization in fine particulates.

  11. Determination of selenium in human spermatozoa and prostasomes using base digestion and electrothermal atomic absorption spectrophotometry.

    Science.gov (United States)

    Suistomaa, U; Saaranen, M; Vanha-Perttula, T

    1987-10-15

    A method for the determination of selenium in human spermatozoa and prostasomes is described. The samples were digested with 25% (w/v) tetramethylammonium hydroxide (TMAH) in methanol and analyzed by atomic absorption spectrometry with electrothermal atomization and Zeeman background correction (ET-AAS). Nickel was used as a matrix modifier. Calibration was performed using the matrix-based calibration curve. The TMAH-digestion method agreed well with a conventional digestion procedure using concentrated nitric acid. The TMAH-digestion does not require heating or strong acids and it was suitable for small biological samples. The average recovery of added selenium in spermatozoan digests was 95.1 +/- 5.2% (n = 5). The coefficient of variation was 9.1% (n = 21). The accuracy of the method tested with the NBS standard 1577 (bovine liver, certified at 1.1 +/- 0.1 micrograms Se/g) resulted in a value of 0.98 +/- 0.10 micrograms Se/g (n = 16). The method was further tested in an interlaboratory comparison study.

  12. Determination of trace impurities in titanium dioxide by direct solid sampling electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Docekal, Bohumil [Institute of Analytical Chemistry, Academy of Sciences of the Czech Republic, Veveri 97, CZ-61142, Brno (Czech Republic)], E-mail: docekal@iach.cz; Vojtkova, Blanka [Institute of Materials Science, Faculty of Chemistry, Brno University of Technology, Purkynova 118, CZ-61200 Brno (Czech Republic)

    2007-03-15

    A true direct solid sampling electrothermal atomic absorption spectrometry method with Zeeman-effect background correction (Analytik Jena ZEEnit 60 AAS) was developed for the determination of As, Cd, Hg, Pb, Sb and Zn in powdered titanium dioxide of pharmaceutical, food and cosmetics grade. The interaction of the titanium matrix and graphite surface of the sample carrier boat in a transversely heated graphite tube atomizer was investigated. Conversion of titanium dioxide to interfering TiO{sub 2}-TiC-liquid phase, running out the sampling boat, was observed at temperatures above 2000 deg. C. The temperature program was optimized accordingly for these volatile analytes in atomization and cleaning steps in order to prevent this interference and to prolong significantly the analytical lifetime of the boat to more than one thousand runs. For all elements, calibration by aqueous standard addition method, by wet-chemically analyzed samples with different content of analytes and/or by dosing one sample in different amounts, were proved as adequate quantification procedures. Linear dynamic calibration working ranges can be considerably expanded up to two orders of magnitude within one measurement run by applying three-field dynamic mode of the Zeeman background correction system. The results obtained by true direct solid sampling technique are compared with those of other independent, mostly wet-chemical methods. Very low limits of detection (3{sigma} criterion) of true solid sampling technique of 21, 0.27, 24, 3.9, 6.3 and 0.9 ng g{sup -1} were achieved for As, Cd, Hg, Pb, Sb and Zn, respectively.

  13. Determination of some antihistaminic drugs by atomic absorption spectrometry and colorimetric methods.

    Science.gov (United States)

    El-Kousy, N; Bebawy, L I

    1999-08-01

    Atomic absorption spectrometry (AAS) and colourimetric methods have been developed for the determination of pizotifen (I), ketotifen (II) and loratadine (III). The first method depends on the reaction of the three drugs (I); (II) and (III) with cobalt thiocyanate reagent at pH 2 to give ternary complexes. These complexes are readily extracted with organic solvent and estimated by indirect atomic absorption method via the determination of the cobalt content in the formed complex after extraction in 0.1 M hydrochloric acid. It was found that the three drugs can be determined in the concentration ranges from 10 to 74, 12 to 95 and 10 to 93 microg ml(-1) with mean percentage recovery of 99.71+/-0.87, 99.70+/-0.79 and 99.62+/-0.75%, respectively. The second method is based on the formation of orange red ion pairs as a result of the reaction between (I); (II) and (III) and molybdenum thiocyanate with maximum absorption at 469.5 nm in dichloromethane. Appropriate conditions were established for the colour reaction. Under the proposed conditions linearity was obeyed in the concentration ranges 3.5-25, 5-37.5 and 2.5-22.5 microg ml(-1) with mean percentage recovery of 99.60+/-0.41, 100.11+/-0.43 and 99.31+/-0.47% for (I): (II) and (III), respectively. The third method depends on the formation of radical ion using 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ). The colour formed was measured at 588 nm for the three drugs (I); (II) and (III), respectively. The method is valid in concentration range 10-80 microg ml(-1) with mean percentage recovery 99.75+/-0.44, 99.94+/-0.72 and 99.17+/-0.36% for (I); (II) and (III), respectively. The proposed methods were applied to the analysis of pharmaceutical preparations. The results obtained were statistically analysed and compared with those obtained by applying the official and reference methods.

  14. Mini-Column Ion-Exchange Separation and Atomic Absorption Quantitation of Nickel, Cobalt, and Iron: An Undergraduate Quantitative Analysis Experiment.

    Science.gov (United States)

    Anderson, James L.; And Others

    1980-01-01

    Presents an undergraduate quantitative analysis experiment, describing an atomic absorption quantitation scheme that is fast, sensitive and comparatively simple relative to other titration experiments. (CS)

  15. Absorption-Amplification Response with or Without Spontaneously Generated Coherence in a Coherent Four-Level Atomic Medium

    Institute of Scientific and Technical Information of China (English)

    LI Jia-Hua; YANG Wen-Xing; PENG Ju-Cun

    2004-01-01

    We discuss and analyze the absorption-amplification properties of a weak probe field in a typical four-level atomic system in the presence of an additional coherence term, the spontaneously generated coherence term. Theinfluences of the spontaneously generated coherence and a coherent pump field on the probe absorption (amplification)are investigated in detail. We show that the absorption of such a weak probe field can be dramatically enhanced dueto the presence of the spontaneously generated coherence. At the same time, the probe-absorption profile exhibitsthe double-peak structure and the probe-absorption peak gradually decreases as the pump intensity increases. On thecontrary, the amplification of such a weak probe field near the line center of the probe transition can be achieved byadjusting the coherent pump field intensity in the absence of the spontaneously generated coherence.

  16. Absorption-amplification response with or without spontaneously generated coherence effect in a four-level atomic system

    Institute of Scientific and Technical Information of China (English)

    Jiahua Li(李家华); Wenxing Yang(杨文星); Jucun Peng(彭菊村)

    2004-01-01

    We discuss and analyze the absorption properties of a weak probe field in a typical four-level atomic system in the presence of a spontaneously generated coherence (SGC) term. The influences of the SGC and a coherent pump field on the probe absorption-amplification are investigated. The results show that the absorption of such a weak probe field can be dramatically enhanced due to the SGC effect. At the same time, the probe-absorption profile exhibits a two-peak structure and the probe-absorption peak gradually decreases as the pump intensity increases. On the contrary, the amplification of such a weak probe field near the line center of the probe transition can be achieved by adjusting the coherent pump field intensity in the absence of the SGC effect.

  17. Absorption-Amplification Response with or Without Spontaneously Generated Coherence in a Coherent Four-Level Atomic Medium

    Institute of Scientific and Technical Information of China (English)

    LIJia-Hua; YANGWen-Xing; PENGJu-Cun

    2004-01-01

    We discuss and analyze the absorption-amplification properties of a weak probe field in a typical fourlevel atomic system in the presence of an additional coherence term, the spontaneously generated coherence term. The influences of the spontaneously generated coherence and a coherent pump field on the probe absorption (amplification) are investigated in detail. We show that the absorption of such a weak probe field can be dramatically enhanced due to the presence of the spontaneously generated coherence. At the same time, the probe-absorption profile exhibits the double-peak structure and the probe-absorption peak gradually decreases as the pump intensity increases. On the contrary, the amplification of such a weak probe field near the line center of the probe transition can be achieved by adiusting the coherent Dump field intensity in the absence of the spontaneously generated coherence.

  18. Autler-Townes doublet in the absorption spectra for the transition between excited states of cold cesium atoms

    Institute of Scientific and Technical Information of China (English)

    Liang Qiang-Bing; Yang Bao-Dong; Yang Jian-Feng; Zhang Tian-Cai; Wang Jun-Min

    2010-01-01

    Autler-Townes splitting in absorption spectra of the excited states 6 2P3/2 - 82S1/2 of cold cesium atoms confined in a magneto-optical trap has been observed.Experimental data of the Autler-Townes splitting fit well to the dressedatom theory,by which the fact of the cold atoms dressed by cooling/trapping laser beams is revealed.The results of the theoretical fitting with experiment not only told us the effective Rabi frequency cold atoms experienced,but also could be used for measuring the probability amplitudes of the dressed states.

  19. Simultaneous determination of cadmium and lead in wine by electrothermal atomic absorption spectrometry

    Science.gov (United States)

    Freschi, Gian P. G.; Dakuzaku, Carolina S.; de Moraes, Mercedes; Nóbrega, Joaquim A.; Gomes Neto, José A.

    2001-10-01

    A method has been developed for the direct simultaneous determination of Cd and Pb in white and red wine by electrothermal atomic absorption spectrometry (ET-AAS) using a transversely heated graphite tube atomizer (THGA) with longitudinal Zeeman-effect background correction. The thermal behavior of both analytes during pyrolysis and atomization stages were investigated in 0.028 mol l -1 HNO 3 and in 1+1 v/v diluted wine using mixtures of Pd(NO 3) 2+Mg(NO 3) 2 and NH 4H 2PO 4+Mg(NO 3) 2 as chemical modifiers. With 5 μg Pd+3 μg Mg as the modifiers and a two-step pyrolysis (10 s at 400°C and 10 s at 600°C), the formation of carbonaceous residues inside the atomizer was avoided. For 20 μl of sample (wine+0.056 mol l -1 HNO 3, 1+1, v/v) dispensed into the graphite tube, analytical curves in the 0.10-1.0 μg l -1 Cd and 5.0-50 μg l -1 Pb ranges were established. The characteristic mass was approximately 0.6 pg for Cd and 33 pg for Pb, and the lifetime of the tube was approximately 400 firings. The limits of detection (LOD) based on integrated absorbance (0.03 μg l -1 for Cd, 0.8 μg l -1 for Pb) exceeded the requirements of Brazilian Food Regulations (decree #55871 from Health Department), which establish the maximum permissible level for Cd at 200 μg l -1 and for Pb at 500 μg l -1. The relative standard deviations ( n=12) were typically wine samples varied from 88 to 107% and 93 to 103%, respectively. The accuracy of the direct determination of Cd and Pb was checked for 10 table wines by comparing the results with those obtained for digested wine using single-element ET-AAS, which were in agreement at the 95% confidence level.

  20. Sapphire: a better material for atomization and in situ collection of silver volatile species for atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Musil, Stanislav, E-mail: stanomusil@biomed.cas.cz; Matoušek, Tomáš; Dědina, Jiří

    2015-06-01

    Sapphire is presented as a high temperature and corrosion resistant material of an optical tube of an atomizer for volatile species of Ag generated by the reaction with NaBH{sub 4}. The modular atomizer design was employed which allowed to carry out the measurements in two modes: (i) on-line atomization and (ii) in situ collection (directly in the optical tube) by means of excess of O{sub 2} over H{sub 2} in the carrier gas during the trapping step and vice versa in the volatilization step. In comparison with quartz atomizers, the sapphire tube atomizer provides a significantly increased atomizer lifetime as well as substantially improved repeatability of the Ag in situ collection signals shapes. In situ collection of Ag in the sapphire tube atomizer was highly efficient (> 90%). Limit of detection in the on-line atomization mode and in situ collection mode, respectively, was 1.2 ng ml{sup −1} and 0.15 ng ml{sup −1}. - Highlights: • Sapphire was tested as a new material of an atomizer tube for Ag volatile species. • Two measurement modes were investigated: on-line atomization and in situ collection. • In situ collection of Ag was highly efficient (> 90%) with LOD of 0.15 ng ml{sup −1}. • No devitrification of the sapphire tube observed in the course of several months.

  1. Influence of phosphorus and calcium on flame atomic absorption spectrophotometric determination of lead in canned fish products.

    Science.gov (United States)

    Serra, T M; Serrano, J F

    1984-01-01

    Lead was determined in the presence of whole multiples of the P/Ca ratio found in Portuguese canned fish by flame atomic absorption spectrophotometry with and without using an ashing aid. Under our experimental conditions, use of the ashing aid eliminates P and Ca interference. Results with real samples, spiked with 1, 2, 3, and 4 ppm lead, are presented and statistically treated.

  2. Identifying Student and Teacher Difficulties in Interpreting Atomic Spectra Using a Quantum Model of Emission and Absorption of Radiation

    Science.gov (United States)

    Savall-Alemany, Francisco; Domènech-Blanco, Josep Lluís; Guisasola, Jenaro; Martínez-Torregrosa, Joaquín

    2016-01-01

    Our study sets out to identify the difficulties that high school students, teachers, and university students encounter when trying to explain atomic spectra. To do so, we identify the key concepts that any quantum model for the emission and absorption of electromagnetic radiation must include to account for the gas spectra and we then design two…

  3. A COMPARISON OF A SPECTROPHOTOMETRIC (QUERCETIN) METHOD AND AN ATOMIC-ABSORPTION METHOD FOR DETERMINATION OF TIN IN FOOD

    DEFF Research Database (Denmark)

    Engberg, Å

    1973-01-01

    Procedures for the determination of tin in food, which involve a spectrophotometric method (with the quercetin-tin complex) and an atomic-absorption method, are described. The precision of the complete methods and of the individual analytical steps required is evaluated, and the parameters...

  4. Overcoming Matrix Effects in a Complex Sample: Analysis of Multiple Elements in Multivitamins by Atomic Absorption Spectroscopy

    Science.gov (United States)

    Arnold, Randy J.; Arndt, Brett; Blaser, Emilia; Blosser, Chris; Caulton, Dana; Chung, Won Sog; Fiorenza, Garrett; Heath, Wyatt; Jacobs, Alex; Kahng, Eunice; Koh, Eun; Le, Thao; Mandla, Kyle; McCory, Chelsey; Newman, Laura; Pithadia, Amit; Reckelhoff, Anna; Rheinhardt, Joseph; Skljarevski, Sonja; Stuart, Jordyn; Taylor, Cassie; Thomas, Scott; Tse, Kyle; Wall, Rachel; Warkentien, Chad

    2011-01-01

    A multivitamin tablet and liquid are analyzed for the elements calcium, magnesium, iron, zinc, copper, and manganese using atomic absorption spectrometry. Linear calibration and standard addition are used for all elements except calcium, allowing for an estimate of the matrix effects encountered for this complex sample. Sample preparation using…

  5. A Simplified Digestion Protocol for the Analysis of Hg in Fish by Cold Vapor Atomic Absorption Spectroscopy

    Science.gov (United States)

    Kristian, Kathleen E.; Friedbauer, Scott; Kabashi, Donika; Ferencz, Kristen M.; Barajas, Jennifer C.; O'Brien, Kelly

    2015-01-01

    Analysis of mercury in fish is an interesting problem with the potential to motivate students in chemistry laboratory courses. The recommended method for mercury analysis in fish is cold vapor atomic absorption spectroscopy (CVAAS), which requires homogeneous analyte solutions, typically prepared by acid digestion. Previously published digestion…

  6. VUV absorption spectroscopy measurements of the role of fast neutral atoms in high-power gap breakdown

    Energy Technology Data Exchange (ETDEWEB)

    FILUK,A.B.; BAILEY,JAMES E.; CUNEO,MICHAEL E.; LAKE,PATRICK WAYNE; NASH,THOMAS J.; NOACK,DONALD D.; MARON,Y.

    2000-03-20

    The maximum power achieved in a wide variety of high-power devices, including electron and ion diodes, z pinches, and microwave generators, is presently limited by anode-cathode gap breakdown. A frequently-discussed hypothesis for this effect is ionization of fast neutral atoms injected throughout the anode-cathode gap during the power pulse. The authors describe a newly-developed diagnostic tool that provides the first direct test of this hypothesis. Time-resolved vacuum-ultraviolet absorption spectroscopy is used to directly probe fast neutral atoms with 1 mm spatial resolution in the 10 mm anode-cathode gap of the SABRE 5 MV, 1 TW applied-B ion diode. Absorption spectra collected during Ar RF glow discharges and with CO{sub 2} gas fills confirm the reliability of the diagnostic technique. Throughout the 50--100 ns ion diode pulses no measurable neutral absorption is seen, setting upper limits of 0.12--1.5 x 10{sup 14} cm{sup {minus}3} for ground state fast neutral atom densities of H, C, N, O, F. The absence of molecular absorption bands also sets upper limits of 0.16--1.2 x 10{sup 15} cm{sup {minus}3} for common simple molecules. These limits are low enough to rule out ionization throughout the gap as a breakdown mechanism. This technique can now be applied to quantify the role of neutral atoms in other high-power devices.

  7. Determination of nickel by flame atomic-absorption spectrophotometry after separation by adsorption of its nioxime complex on microcrystalline naphthalene.

    Science.gov (United States)

    Nagahiro, T; Puri, B K; Katyal, M; Satake, M

    1984-11-01

    A method has been developed for the determination of nickel in alloys by flame atomic-absorption spectrophotometry after formation of a water-insoluble complex, its adsorption on microcrystalline naphthalene, and dissolution of the complex and naphthalene in nitric acid and xylene.

  8. Hydrogen atom temperature measured with wavelength-modulated laser absorption spectroscopy in large scale filament arc negative hydrogen ion source

    Energy Technology Data Exchange (ETDEWEB)

    Nakano, H., E-mail: nakano@nifs.ac.jp; Goto, M.; Tsumori, K.; Kisaki, M.; Ikeda, K.; Nagaoka, K.; Osakabe, M.; Takeiri, Y.; Kaneko, O. [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 5095292 (Japan); Nishiyama, S.; Sasaki, K. [Graduate school of Engineering, Hokkaido University, Kita 13, Nishi 8, Kita-ku, Sapporo 0608628 (Japan)

    2015-04-08

    The velocity distribution function of hydrogen atoms is one of the useful parameters to understand particle dynamics from negative hydrogen production to extraction in a negative hydrogen ion source. Hydrogen atom temperature is one of the indicators of the velocity distribution function. To find a feasibility of hydrogen atom temperature measurement in large scale filament arc negative hydrogen ion source for fusion, a model calculation of wavelength-modulated laser absorption spectroscopy of the hydrogen Balmer alpha line was performed. By utilizing a wide range tunable diode laser, we successfully obtained the hydrogen atom temperature of ∼3000 K in the vicinity of the plasma grid electrode. The hydrogen atom temperature increases as well as the arc power, and becomes constant after decreasing with the filling of hydrogen gas pressure.

  9. Comparisons of selected methods for the determination of kinetic parameters from electrothermal atomic absorption data

    Science.gov (United States)

    Fonseca, Rodney W.; Pfefferkorn, Lisa L.; Holcombe, James A.

    1994-12-01

    Three of the methods available for the determination of kinetic parameters for atom formation in ETAAS were compared. In the approach of mcnally and holcombe [ Anal. Chem. 59, 1015 (1987)], Arrhenius-type plots are used to extract activation energy values while an approximation of the order of release is obtained by studying the alignment of the absorption maxima at increasing analyte concentrations. In the method of rojas and olivares [ Spectrochim. Acta47B, 387 (1992)], plots are prepared for different orders of release, with the correct order yielding a longer linear region from whose slope the activation energy is calculated. The method of yan et al. [ Spectrochim. Acta48B, 605 (1993)] uses a single absorption profile for the calculations. Activation energy and the order of release are obtained from the slope and intercept, respectively, on their graph. All three methods assume linear heating rate, constant activation energies, and furnace isothermality. The methods were tested with the same experimental data sets for Cu, Au and Ni using a spatially isothermal cuvette. Since intensive mathematical treatments commonly have deleterious effects on the uncertainty of the final result, the methods were compared using both the original data and a smoothed version of it. In general, the three methods yielded comparable results for the metals studied. However, choosing the most linear plot to determine the correct order of release when using Rojas and Olivares' method was sometimes subjective, and McNally and Holcombe's method provided only estimates for the orders of release that were neither zero nor unity.

  10. Absolute number densities of helium metastable atoms determined by atomic absorption spectroscopy in helium plasma-based discharges used as ambient desorption/ionization sources for mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Reininger, Charlotte; Woodfield, Kellie [Brigham Young University, Department of Chemistry and Biochemistry, Provo, UT 84602 (United States); Keelor, Joel D.; Kaylor, Adam; Fernández, Facundo M. [Georgia Institute of Technology, School of Chemistry and Biochemistry, Atlanta, GA 30332 (United States); Farnsworth, Paul B., E-mail: paul_farnsworth@byu.edu [Brigham Young University, Department of Chemistry and Biochemistry, Provo, UT 84602 (United States)

    2014-10-01

    The absolute number densities of helium atoms in the 2s {sup 3}S{sub 1} metastable state were determined in four plasma-based ambient desorption/ionization sources by atomic absorption spectroscopy. The plasmas included a high-frequency dielectric barrier discharge (HF-DBD), a low temperature plasma (LTP), and two atmospheric-pressure glow discharges, one with AC excitation and the other with DC excitation. Peak densities in the luminous plumes downstream from the discharge capillaries of the HF-DBD and the LTP were 1.39 × 10{sup 12} cm{sup −3} and 0.011 × 10{sup 12} cm{sup −3}, respectively. Neither glow discharge produced a visible afterglow, and no metastable atoms were detected downstream from the capillary exits. However, densities of 0.58 × 10{sup 12} cm{sup −3} and 0.97 × 10{sup 12} cm{sup −3} were measured in the interelectrode regions of the AC and DC glow discharges, respectively. Time-resolved measurements of metastable atom densities revealed significant random variations in the timing of pulsed absorption signals with respect to the voltage waveforms applied to the discharges. - Highlights: • We determine He metastable number densities for four plasma types • The highest number densities were observed in a dielectric barrier discharge • No helium metastable atoms were observed downstream from the exits of glow discharges.

  11. High purity polyimide analysis by solid sampling graphite furnace atomic absorption spectrometry

    Science.gov (United States)

    Santos, Rafael F.; Carvalho, Gabriel S.; Duarte, Fabio A.; Bolzan, Rodrigo C.; Flores, Erico M. M.

    2017-03-01

    In this work, Cr, Cu, Mn, Na and Ni were determined in high purity polyimides (99.5%) by solid sampling graphite furnace atomic absorption spectrometry (SS-GFAAS) using Zeeman effect background correction system with variable magnetic field, making possible the simultaneous measurement at high or low sensitivity. The following analytical parameters were evaluated: pyrolysis and atomization temperatures, feasibility of calibration with aqueous solution, linear calibration range, sample mass range and the use of chemical modifier. Calibration with aqueous standard solutions was feasible for all analytes. No under or overestimated results were observed and up to 10 mg sample could be introduced on the platform for the determination of Cr, Cu, Mn, Na and Ni. The relative standard deviation ranged from 3 to 20%. The limits of detection (LODs) achieved using the high sensitivity mode were as low as 7.0, 2.5, 1.7, 17 and 0.12 ng g- 1 for Cr, Cu, Mn, Na and Ni, respectively. No addition of chemical modifier was necessary, except for Mn determination where Pd was required. The accuracy was evaluated by analyte spike and by comparison of the results with those obtained by inductively coupled plasma optical emission spectrometry and inductively coupled plasma mass spectrometry after microwave-assisted digestion in a single reaction chamber system and also by neutron activation analysis. No difference among the results obtained by SS-GFAAS and those obtained by alternative analytical methods using independent techniques. SS-GFAAS method showed some advantages, such as the determination of metallic contaminants in high purity polyimides with practically no sample preparation, very low LODs, calibration with aqueous standards and determination in a wide range of concentration.

  12. Gas chromatography coupled with atomic absorption spectrometry — a sensitive instrumentation for mercury speciation

    Science.gov (United States)

    Emteborg, Håkan; Sinemus, Hans-Werner; Radziuk, Bernard; Baxter, Douglas C.; Frech, Wolfgang

    1996-07-01

    New instrumentation for the speciation of mercury is described, and is applied to the analysis of natural water samples. The separation of mercury species is effected using gas chromatography of derivatized mercury species on a widebore capillary column. The solvent is vented using a bypass valve and the separated mercury species are pyrolysed on-line at 800°C for production of mercury atoms. These are then detected by atomic absorption spectrometry (AAS) at the 253.7 and 184.9 nm lines simultaneously in a quartz cuvette. The use of the 184.9 nm line provides a more than five-fold increase in sensitivity compared with the conventional 253.7 nm line and an absolute detection limit of 0.5 pg of mercury. The dynamic range of the combined analytical lines provides a linear response over more than three orders of magnitude. A number of organic compounds not containing mercury are also detected following pyrolysis, especially at the 184.9 nm line. These background species must not co-elute at the retention times for methyl- and inorganic mercury, as otherwise a positive interference would result. By maximizing the chromatographic resolution and minimizing the band broadening in the cuvette by use of a make-up gas, the retention times of interest are freed from co-eluting background peaks. The instrumentation has been applied to the determination of ng l -1 concentrations of methyl- and inorganic mercury in Lake Constance, Germany and within the Lake Constance drinking water supply organization, Bodenseewasserversorgung (BWV). The accuracy for the sum of methyl- and inorganic mercury has been assessed by comparison with an independent method for total mercury based on AAS detection implemented at BWV. Relative detection limits using 1 litre water samples and 15 ml injections of the final hexane extract were 0.03 ng l -1 for methylmercury and 0.4 ng l -1 for inorganic mercury based on the 3j criterion.

  13. A photo-oxidation procedure using UV radiation/H{sub 2}O{sub 2} for decomposition of wine samples - Determination of iron and manganese content by flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Walter N.L. dos [Departamento de Ciencias Exatas e da Terra, Universidade do Estado da Bahia, Salvador, Bahia (Brazil); Universidade Federal da Bahia, Instituto de Quimica, Campus Ondina, Salvador, Bahia, 40170-290 Brazil (Brazil)], E-mail: wlopes@uneb.br; Brandao, Geovani C.; Portugal, Lindomar A.; David, Jorge M.; Ferreira, Sergio L.C. [Universidade Federal da Bahia, Instituto de Quimica, Campus Ondina, Salvador, Bahia, 40170-290 Brazil (Brazil)

    2009-06-15

    This paper proposes the use of photo-oxidation with UV radiation/H{sub 2}O{sub 2} as sample pretreatment for the determination of iron and manganese in wines by flame atomic absorption spectrometry (FAAS). The optimization involved the study of the following variables: pH and concentration of buffer solution, concentrated hydrogen peroxide volume and irradiation time. The evaluation of sample degradation was monitored by measuring the absorbance at the maximum wavelength of red wine (530 nm). Using the experimental conditions established during the optimization (irradiation time of 30 min, oxidant volume of 2.5 mL, pH 10, and a buffer concentration of 0.15 mol L{sup - 1}), this procedure allows the determination of iron and manganese with limits of detection of 30 and 22 {mu}g L{sup - 1}, respectively, for a 5 mL volume of digested sample. The precision levels, expressed as relative standard deviation (RSD), were 2.8% and 0.65% for iron and 2.7% and 0.54% for manganese for concentrations of 0.5 and 2.0 mg L{sup - 1}, respectively. Addition/recovery tests for evaluation of the accuracy were in the ranges of 90%-111% and 95%-107% for iron and manganese, respectively. This digestion procedure has been applied for the determination of iron and manganese in six wine samples. The concentrations varied from 1.58 to 2.77 mg L{sup - 1} for iron and from 1.30 to 1.91 mg L{sup - 1} for manganese. The results were compared with those obtained by an acid digestion procedure and determination of the elements by FAAS. There was no significant difference between the results obtained by the two methods based on a paired t-test (at 95% confidence level)

  14. Determination of nickel in active pharmaceutical ingredients by electrothermal atomic absorption spectrometry.

    Science.gov (United States)

    Bubnič, Zoran; Urleb, Uroš; Kreft, Katjuša; Veber, Marjan

    2010-03-01

    An electrothermal atomic absorption spectrometric procedure for the determination of nickel in active pharmaceutical ingredients was developed. Since the recoveries of nickel by the direct dissolution of samples in diluted nitric acid were low and caused errors in the determination of Ni in pharmaceutical samples, different approaches for sample pre-treatment were examined. It was found that the microwave digestion was the most suitable way for sample preparation. Various combinations of digestion agents and different microwave conditions were tested. The combination of nitric acid and hydrogen peroxide was found to be the most appropriate. The validity of the method was evaluated by recovery studies of spiked samples and by the comparison of the results obtained by inductively coupled plasma mass spectrometry (ICP-MS). The recovery ranged from 87.5 to 104.0% and a good agreement was achieved between both methods. The detection limit and the limit of quantification were 0.6 and 2.1 µg g-1 respectively. The precision of the method was confirmed by the determination of Ni in the spiked samples and was below 4%, expressed in terms of a relative standard deviation. The method was applied to the determination of nickel in production samples of active pharmaceutical ingredients and intermediates.

  15. Determination of arsenic in a nickel alloy by flow injection hydride generation atomic absorption spectrometry

    Science.gov (United States)

    Hanna, C. P.; Tyson, J. F.; Offley, S. G.

    1992-08-01

    The development of a method for the direct determination of trace arsenic quantities in nickel alloy digests, by flow injection hydride generation atomic absorption spectrometry, is described. An optimization study of the manifold and chemical parameters produced system performance, in terms of tolerance of the nickel matrix and sensitivity, such that matrix removal and pre-reduction of As(V) to As (III) prior to arsine generation were eliminated. Full recovery of the As(V) signal from a solution containing 5 ng ml -1 in the presence of 60 μg ml -1 nickel was obtained. Validation of the method was achieved by analyzing a British Chemical Standard (BCS) Certified Reference Material (CRM) #346 IN nickel alloy containing arsenic at a concentration of 50 μg g -1. Following dissolution in nitric and hydrofluoric acids by a microwave assisted procedure, the only subsequent preparation required was dilution by the appropriate factor. Up to 60 injections h -1 may be made, with a detection limit of 0.5 ng ml -1 arsenic (250 pg absolute) as As(V) in a 500 μl sample. The peak height characteristic concentration is 0.46 ng ml -1, with a relative standard deviation of 3.5% for a 10 ng ml -1 As(V) standard ( n = 6).

  16. Speciation analysis of iron in traditional Chinese medicine by flame atomic absorption spectrometry.

    Science.gov (United States)

    Li, Shun-Xing; Deng, Nan-Sheng

    2003-04-24

    In view of octanol, a long-chain alkanol, resembled as the configuration of carbohydrate and adipose in human body, the octanol-solubility and water-solubility were used to define the species of iron in medicine, to identify the lipophily and bioavailability of coordinated iron complex, and octanol-water system was adopted to study the distribution of iron in decoction of eight single medicines and compatibility of semen persicae and flos carthami in stomach and intestine. To study the effect of compatibility of medicines, the different acidity of stomach and intestine on the species of iron in phytomedicine decoction, the total concentration, octanol- and water-solubility concentration of iron in medicinal materials or decoctions under gastric and intestinal acidity, were determined, respectively, by flame atomic absorption spectrometry, analyzed and compared. The different acidity of digestive site, the different composition of medicine, and the compatibility of medicines, have greatly affected the species of iron, the pharmacological activity of coordinated iron complex in decoctions. Such factors, especially the concentration of octanol-solubility iron, could be the basis of the dosage to avoid iron overload.

  17. Assessment of toxic metals in raw and processed milk samples using electrothermal atomic absorption spectrophotometer.

    Science.gov (United States)

    Kazi, Tasneem Gul; Jalbani, Nusrat; Baig, Jameel Ahmed; Kandhro, Ghulam Abbas; Afridi, Hassan Imran; Arain, Mohammad Balal; Jamali, Mohammad Khan; Shah, Abdul Qadir

    2009-09-01

    Milk and dairy products have been recognized all over the world for their beneficial influence on human health. The levels of toxic metals (TMs) are an important component of safety and quality of milk. A simple and efficient microwave assisted extraction (MAE) method has been developed for the determination of TMs (Al, Cd, Ni and Pb), in raw and processed milk samples. A Plackett-Burman experimental design and 2(3)+star central composite design, were applied in order to determine the optimum conditions for MAE. Concentrations of TMs were measured by electrothermal atomic absorption spectrometry. The accuracy of the optimized procedure was evaluated by standard addition method and conventional wet acid digestion method (CDM), for comparative purpose. No significant differences were observed (P>0.05), when comparing the values obtained by the proposed MAE method and CDM (paired t-test). The average relative standard deviation of the MAE method varied between 4.3% and 7.6% based on analyte (n=6). The proposed method was successfully applied for the determination of understudy TMs in milk samples. The results of raw and processed milk indicated that environmental conditions and manufacturing processes play a key role in the distribution of toxic metals in raw and processed milk.

  18. Speciation of iron (II) and (III) by using solvent extraction and flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Yaman, Mehmet [Department of Chemistry, Science and Arts Faculty, Firat University, Elazig (Turkey)]. E-mail: myaman@firat.edu.tr; Kaya, Gokce [Department of Chemistry, Science and Arts Faculty, Firat University, Elazig (Turkey)

    2005-05-17

    A method for speciation, preconcentration and separation of Fe{sup 2+} and Fe{sup 3+} in different matrices was developed using solvent extraction and flame atomic absorption spectrometry. PAN as complexing reagent for Fe{sup 2+} and chloroform as organic solvent were used. The complex of Fe{sup 2+}-PAN was extracted into chloroform phase in the pH range of 0.75-4.0 and Fe{sup 3+} remains in water phase in the pH range 0.75-1.25. The optimum conditions for maximum recovery of Fe{sup 2+} and minimum recovery of Fe{sup 3+} were determined as pH = 1, the stirring time of 20 min, the PAN amount of 0.5 mg and chloroform volume of 8 mL. The developed method was applied to the determination of Fe{sup 2+} and Fe{sup 3+} in tea infusion, fruit juice, cola and pekmez. It is seen that there is high bioavailable iron (Fe{sup 2+}) in pekmez. The developed method is sensitive, simple and need the shorter time in comparison with other similar studies.

  19. Fitness analysis method for magnesium in drinking water with atomic absorption using quadratic curve calibration

    Directory of Open Access Journals (Sweden)

    Esteban Pérez-López

    2014-11-01

    Full Text Available Because of the importance of quantitative chemical analysis in research, quality control, sales of services and other areas of interest , and the limiting of some instrumental analysis methods for quantification with linear calibration curve, sometimes because the short linear dynamic ranges of the analyte, and sometimes by limiting the technique itself, is that there is a need to investigate a little more about the convenience of using quadratic curves for analytical quantification, which seeks demonstrate that it is a valid calculation model for chemical analysis instruments. To this was taken as an analysis method based on the technique and atomic absorption spectroscopy in particular a determination of magnesium in a sample of drinking water Tacares sector Northern Grecia, employing a nonlinear calibration curve and a curve specific quadratic behavior, which was compared with the test results obtained for the same analysis with a linear calibration curve. The results show that the methodology is valid for the determination referred to, with all confidence, since the concentrations are very similar, and as used hypothesis testing can be considered equal.

  20. Atomic Structure of Pt3Ni Nanoframe Electrocatalysts by in Situ X-ray Absorption Spectroscopy.

    Science.gov (United States)

    Becknell, Nigel; Kang, Yijin; Chen, Chen; Resasco, Joaquin; Kornienko, Nikolay; Guo, Jinghua; Markovic, Nenad M; Somorjai, Gabor A; Stamenkovic, Vojislav R; Yang, Peidong

    2015-12-23

    Understanding the atomic structure of a catalyst is crucial to exposing the source of its performance characteristics. It is highly unlikely that a catalyst remains the same under reaction conditions when compared to as-synthesized. Hence, the ideal experiment to study the catalyst structure should be performed in situ. Here, we use X-ray absorption spectroscopy (XAS) as an in situ technique to study Pt3Ni nanoframe particles which have been proven to be an excellent electrocatalyst for the oxygen reduction reaction (ORR). The surface characteristics of the nanoframes were probed through electrochemical hydrogen underpotential deposition and carbon monoxide electrooxidation, which showed that nanoframe surfaces with different structure exhibit varying levels of binding strength to adsorbate molecules. It is well-known that Pt-skin formation on Pt-Ni catalysts will enhance ORR activity by weakening the binding energy between the surface and adsorbates. Ex situ and in situ XAS results reveal that nanoframes which bind adsorbates more strongly have a rougher Pt surface caused by insufficient segregation of Pt to the surface and consequent Ni dissolution. In contrast, nanoframes which exhibit extremely high ORR activity simultaneously demonstrate more significant segregation of Pt over Ni-rich subsurface layers, allowing better formation of the critical Pt-skin. This work demonstrates that the high ORR activity of the Pt3Ni hollow nanoframes depends on successful formation of the Pt-skin surface structure.

  1. Determination of toxic metals in some herbal drugs through atomic absorption spectroscopy.

    Science.gov (United States)

    Hina, Bushra; Rizwani, Ghazala Hafeez; Naseem, Shahid

    2011-07-01

    This study presents a picture of occurrence of heavy metals (Pb, Cd, Cu, Cr, Co, Fe, Ni, Zn) in some selected valuable herbal drugs (G. glabra, O. bracteatum, V. odorata , F. vulgare, C. cyminum, C. sativum, and Z. officinalis) purchased from three different zones (southern, eastern, and western) of Karachi city using atomic absorption spectrophotometer. Heavy metal concentrations in these drugs were found in the range of: 3.26-30.46 for Pb, 1.6-4.91 for Cd, 0.65-120.21 for Cu, 83.74-433.76 for Zn, 1.61-186.75 for Cr, 0.48-76.97 for Ni, 5.54-77.97 for Co and 65.68-1652.89 µg/g for Fe. Percentage of heavy metals that were found beyond the permissible limits were: 71.4% for Pb, 28.51% for Cd, 14.2% for Cu, and 9.5 % for Cr. Significant difference was noticed for each heavy metal among herbal drugs as well as their zones of collection using two way ANOVA followed by least significant (LSD) test at p<0.05.Purpose of this research is to detect each type of heavy metal contaminant of herbal drugs by environmental pollution, as well as to highlight the health risks associated with the use of such herbal drugs that contain high levels of toxic heavy metals.

  2. Speciation of methylmercury in market seafood by thermal degradation, amalgamation and atomic absorption spectroscopy.

    Science.gov (United States)

    Ruiz-de-Cenzano, Manuela; Rochina-Marco, Arancha; Cervera, M Luisa; de la Guardia, Miguel

    2014-09-01

    Sample thermal decomposition followed by mercury amalgamation and atomic absorption has been employed for the determination of methylmercury (MeHg) in fish. The method involves HBr leaching of MeHg, extraction into toluene, and back-extraction into an aqueous l-cysteine solution. Preliminary studies were focused on the extraction efficiency, losses, contaminations, and species interconversion prevention. The limit of detection was 0.018µgg(-1) (dry weight). The intraday precision for three replicate analysis at a concentration of 4.2µgg(-1) (dry weight) was 3.5 percent, similar to the interday precision according to analysis of variance (ANOVA). The accuracy was guaranteed by the use of fortified samples involving 83-105 percent recoveries, and certified reference materials TORT-2 (lobster hepatopancreas) and DORM-3 (dogfish liver), providing 107 and 98 percent recovery of certified values. The greenness of the method was also evaluated with the analytical eco-scale being obtained a final score of 73 points which means an acceptable green analysis. The method was applied to fifty-seven market samples of different fish acquired from local markets in several sampling campaigns. The content of MeHg found varied between 0.0311 and 1.24µgg(-1) (wet weight), with values that involve 33-129 percent of the total mercury content. Some considerations about food safety were also done taking into account data about Spanish fish consume and Tolerable Weekly Intake (TWI) established for MeHg.

  3. Detection of Glucose with Atomic Absorption Spectroscopy by Using Oligonucleotide Functionalized Gold Nanoparticle.

    Science.gov (United States)

    Zhang, Hong; Yan, Honglian; Ling, Liansheng

    2016-06-01

    A novel method for the detection of glucose was established with atomic absorption spectroscopy by using the label of gold nanoparticle (AuNP). Silver-coated glass assembled with oligonucleotide 5'-SH-T12-AGA CAA GAG AGG-3' (Oligo 1) was acted as separation probe, oligonucleotide 5'-CAA CAG AGA ACG-T12-SH-3' modified gold nanoparticle (AuNP-Oligo 2) was acted as signal-reporting probe. Oligonucleotide 5'-CGT TCT CTG TTG CCT CTC TTG TCT-3' (Oligo 3) could hybridize with Oligo 1 on the surface of silver-coated glass and AuNP-Oligo 2, and free AuNP-Oligo 2 could be removed by rinsing with buffer. Hence the concentration of Oligo 3 was transformed into the concentration of gold element. In addition, Oligo 3 could be cleaved into DNA fragments by glucose, glucose oxidase and Fe(2+)-EDTA through Fenton reaction. Thereby the concentration of glucose could be transformed to the absorbance of gold element. Under the optimum conditions, the integrated absorbance decreased proportionally to the concentration of glucose over the range from 50.0 μM to 1.0 mM with a detection limit of 40.0 μM. Moreover, satisfactory result was obtained when the assay was used to determinate glucose in human serum.

  4. Determination of firing distance. Lead analysis on the target by atomic absorption spectroscopy (AAS).

    Science.gov (United States)

    Gagliano-Candela, Roberto; Colucci, Anna P; Napoli, Salvatore

    2008-03-01

    This paper reports a method for the determination of the firing distance. Atomic absorption spectroscopy (AAS) was used to determine the lead (Pb) pattern around bullet holes produced by shots on test targets from the gun. Test shots were made with a Colt 38 Special at 5, 10, 20, 25, 30, 35, 40, 45, 50, 60, 80, and 100 cm target distance. The target was created with sheets of Whatman no. 1 paper on a polystyrene support. The target was subdivided into three carefully cut out rings (1, 2, and 3; with external diameters of 1.4 cm; 5 cm; 10.2 cm, respectively). Each sample was analyzed with graphite furnace AAS. Lead values analysis performed for each ring yielded a linear relation between the firing distance (cm) and the logarithm of lead amounts (microg/cm(2)) in definite target areas (areas 2 + 3): [ln dPb(2+3) = a(0) + a(1)l]; where dPb(2+3) = lead microg/cm(2) of area 2 + 3; a(0) and a(1) are experimentally calculated; l = distance in cm.

  5. Measurement of nickel, cobalt and chromium in toy make-up by atomic absorption spectroscopy.

    Science.gov (United States)

    Corazza, Monica; Baldo, Federica; Pagnoni, Antonella; Miscioscia, Roberta; Virgili, Annarosa

    2009-01-01

    Cosmetics should not contain more than 5 ppm of nickel, chromium or cobalt and, in order to minimize the risk of sensitization in very sensitive subjects, the target amount should be as low as 1 ppm. However, there are no published reports on the presence of these metals in toy make-up. This study analysed 52 toy make-ups using atomic absorption spectroscopy. More than 5 ppm of nickel was present in 14/52 (26.9%) samples. Chromium exceeded 5 ppm in 28/52 (53.8%) samples, with values over 1000 ppm in 3 eye shadows. Cobalt was present in amounts over 5 ppm in 5/52 (9.6%) samples. Powdery toy make-up (eye shadows) had the highest levels of metals, and "creamy" toy make-up (lip gloss and lipsticks) the lowest. Toy make-ups are potentially sensitizing items, especially for atopic children, who have a damaged skin barrier that may favour penetration of allergens.

  6. Improved preparation of small biological samples for mercury analysis using cold vapor atomic absorption spectroscopy.

    Science.gov (United States)

    Adair, B M; Cobb, G P

    1999-05-01

    Concentrations of mercury in biological samples collected for environmental studies are often less than 0.1 microgram/g. Low mercury concentrations and small organ sizes in many wildlife species (approximately 0.1 g) increase the difficulty of mercury determination at environmentally relevant concentrations. We have developed a digestion technique to extract mercury from small (0.1 g), biological samples at these relevant concentrations. Mean recoveries (+/- standard error) from validation trials of mercury fortified tissue samples using cold vapor atomic absorption spectroscopy for analysis ranged from 102 +/- 4.3% (2.5 micrograms/L, n = 15) to 108 +/- 1.4% (25 micrograms/L, n = 15). Recoveries of inorganic mercury were 99 +/- 5 (n = 19) for quality assurance samples analyzed during environmental evaluations conducted during a 24 month period. This technique can be used to determine total mercury concentrations of 60 ng Hg/g sample. Samples can be analyzed in standard laboratories in a short time, at minimal cost. The technique is versatile and can be used to determine mercury concentrations in several different matrices, limiting the time and expense of method development and validation.

  7. Direct solid sampling electrothermal atomic absorption spectrometry for the analysis of high-purity niobium pentaoxide.

    Science.gov (United States)

    Huang, M D; Krivan, V

    2000-01-01

    A direct solid sampling electrothermal atomic absorption spectrometry (SoS-ETAAS) method for ultratrace analysis of powdered niobium pentaoxide for Al, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni and Zn has been developed. The elements K, Mg, Na and Zn could be determined without any chemical modification. However, in the determination of the elements Al, Co, Cr, Cu, Fe, Mn and Ni, serious matrix-caused non-spectral interferences and background occurred which made their determination impossible. This problem was remedied by conversion of the niobium pentaoxide matrix into the thermally stable niobium carbide by using methane atmosphere during the pyrolysis stage. The development resulted in establishing an extraordinary powerful method for the analysis of niobium pentaoxide in term of limits of detection, accuracy, simplicity and analysis time. Quantification was performed using calibration curves measured with aqueous standard solutions. The accuracy was checked by comparing the results with those obtained by ETAAS in analysis of slurries and digests of the sample. Due to almost complete freedom of blank and high applicable sample amounts (up to 15 mg), extremely low limits of detection (0.5-2 ng/g) were achieved.

  8. Determination of selenium and tellurium in the gas phase using specific columns and atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Muangnoicharoen, S.; Chiou, K.Y.; Manuel, O.K.

    1986-11-01

    Total selenium and tellurium in the gas phase were analyzed after adsorption on gold-coated beads and charcoal. The thermally eluting gas was trapped on columns filled with quartz beads that were cooled in an ice bath. The beads were boiled in dilute HCl, and the resulting solution was analyzed for Se and Te by graphite furnace atomic absorption spectrometry. Their results demonstrate that gold-coated beads efficiently trap gaseous Se and Te at a low gas flow rate, but at higher flow rates charcoal traps are more expedient. With charcoal traps, it was found that local air samples contain Se in the range of 0.92-3.05 ng m/sup -3/ and Te in the range of 0.10-0.34 ng m/sup -3/. Detection limits down to about 0.1 ng m/sup -3/ allow the ready detection of Se and Te in rural air with a precision of about +/- 6% at the nanogram level of Te and about +/- 4% at the nanogram level of Se.

  9. Speciation Analysis of Serum Copper by Ultrafiltration Com-bined with Graphite Furnace Atomic Absorption Spectrometry

    Institute of Scientific and Technical Information of China (English)

    WANG Zhi-Hua; MA Hui-Min; MA Quan-Li; LIANG Shu-Chuan

    2001-01-01

    UItrafiltration combined with graphite furnace atomic absorp-tion spectrometry(GFAAS)was used to study protein binding and speciation of copper in human serum..UItrafiltration was carried out using a cell unit ultrafiltration membraoes having a nominal cut-off of 10,000Dalton.The effects of var-ious experimental factors including the kind and concentration of electrolyte,sample storge,pH,pressure and the precon-ditioning of the membranes on the speciation analysis of serum copper by ultrafiltration were examined.It was observed that 4.5±2.3% of the total copper in serum was ultrafiltrable and this value did not seem to be influenced by the total serum ele-mental concentration,the PH (6.5——10) adn the pressure(≤1.5kg/cm2).the preconditioning of the ultrafiltration system with 0.1mol/L calcium nitrate can overcome the adsorption loss of copper effectively,and the addition of tris-HCI sohtion (pH 7.4)to serum accelerates the ultrafiltration.The present method was proved to be suitable for speciation analysis for its simplicity,rapidity,small sample reuqirement and easy con-trol.The results obtained with the method are accurate and reliable.

  10. [Atomic absorption spectrophotometry study of copper ion release by copper-bearing intrauterine devices].

    Science.gov (United States)

    Berthou, J; Chrétien, F C; Driguez, P A

    1998-11-01

    Copper release from copper-bearing IUD's was studied in vitro and in vivo using atomic absorption spectrophotometry in deionized water, normal saline solution and normal ovulatory cervical mucus. In these media, copper release from a 375 mm2 DIU occurs without latency, showing comparable amounts for identical time intervals. Daily copper release was shown to be respectively 8 and 11 times higher in cervical mucus and normal saline solution than in deionized water. Although copper ions are detectable in ovulatory cervical mucus under physiological conditions, the copper content appears 5 to 6 times higher in women bearing a copper IUD. Obviously, the copper amount is dependent on the copper exposed surface: the daily in vitro release from a 250 mm2 IUD is 18% inferior to that observed from a 375 mm2 model. In vivo, the daily copper release in ovulatory mucus of 380 or 200 mm2 IUD users is respectively 5 and 3.5 times higher than in controls.

  11. Use of Atomic Absorption Spectrometry in Assessment of Biomonitor Plants for Lead, Cadmium and Copper Pollution

    Institute of Scientific and Technical Information of China (English)

    Gokce Kaya; Mehmet Yaman

    2012-01-01

    Eleven plant species were collected from the vicinity of lead-battery plant in the city of Gaziantep,Turkey.Lead,cadmium and copper concentrations in the soil and leaves of plants were determined by atomic absorption spectrometry.Lead,Cd and Cu concentrations in the soil samples taken from battery area were found to be in the ranges of 304~602,0.4~0.44 and 31~37 mg · kg-1,respectively.Significantly increased lead concentration up to 2 750 mg · kg-1 was found in the leaves of Eleagnus angustifolia L.plant.The lead concentrations in the other plant leaves taken from 50 m around battery factory followed the order Ailanthus altissima >Morus sp.> Juglans regia L.> Ficus carica L.>Cydonia oblonga Miller> Prunus x domestica L.The plants,Populus nigra L.,Eleagnus angustifolia L.and Salix sp.were found useful for Cd,and the plant,Eleagnus angustifolia L.for Pb,to be considered as potential biomonitor.Especially,leaves of trees and plants taken from the distance of 50 m from battery plant have relatively higher Pb concentrations.Therefore,people who and animals which live in this area and benefit from these soil and plants have vital risks.

  12. An indirect atomic absorption spectrometric determination of ciprofloxacin, amoxycillin and diclofenac sodium in pharmaceutical formulations

    Directory of Open Access Journals (Sweden)

    MAHMOUD MOHAMED ISSA

    2008-05-01

    Full Text Available A highly sensitive indirect atomic absorption spectrophotometric (AAS method has been developed for the determination of very low concentrations of ciprofloxacin, amoxycillin and diclofenac sodium. The method is based on the oxidation of these drugs with iron(III. The excess of iron(III was extracted into diethyl ether and then the iron(II in the aqueous layer was aspirated into an air–acetylene flame and determined by AAS. The linear concentration ranges were 25–400, 50–500 and 60–600 ng ml-1 for ciprofloxacin, amoxycillin and diclofenac sodium, respectively. The results were statistically compared with the official method using t- and f-test at p < 0.05. There were insignificant interferences from most of the excipients present. The intra- and inter-day assay coefficients of variation were less than 6.1 % and the recoveries ranged from 95 to 103 %. The method was applied for the analysis of these drug substances in their commercial pharmaceutical formulations.

  13. [The determination of chromium in feeds by flame atomic absorption spectrophotometry].

    Science.gov (United States)

    Wang, Jian; Jia, Bin; Guo, Li-ping; Lin, Qiu-ping

    2005-07-01

    Chromium in feeds is regulated by China Standard GB 13078-2001. A method of flame atomic absorption spectrophotometry for the determination of Cr in feeds has been developed in allusion to shortage of China standard method. Several acetylene flow-rate, burner-high and the additive of interference suppressor NH4Cl were studied respectively on the effect of sensitivities of Cr(III) and Cr(VI). The two sets analytical average results of Cr in feed sample determined by calibration curves of Cr(III) and Cr(VI) were tested by t test, no marked discrepancy was found. Optimum instrumental conditions of Cr(III) and Cr(VI) with same sensitivity were confirmed. Sensitivity was 0.014 microg x mL(-1) with detection limit 0.70 mg x kg(-1). The recoveries were 94.4%-104.9%. Relative standard deviation of sample determination (5-6 times) was 1.90%-4.08%. This method is simply, fast and exact, the detection limit was answered for Cr limit in feeds regulated by GB 13078-2001, it can be applied to the analysis of Cr in feeds.

  14. Determination of iron in natural and mineral waters by flame atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    ROLANDAS KAZLAUSKAS

    2004-05-01

    Full Text Available Simple methods for the determination of Fe in natural and mineral waters by flame atomic absorption spectrometry (AAS are suggested. The results of the investigation of selectivity of the proposed AAS method proved that this procedure is not affected by high concentrations of other metals. The calibration graph for iron was linear at levels near the detection limit up to at least 0.10 mg ml-1. For the determination of microamounts of iron in mineral waters, an extraction AAS technique was developed. Iron was retained as Fe-8-oxyquinoline complex and extracted into chloroform. The optimal conditions for the extraction of the iron complex were determined. The AAS method was applied to the determination of Fe in mineral waters and natural waters from different areas of Lithuania. The accuracy of the developed method was sufficient and evaluated in comparison with a photometric method. The obtained results demonstrated that the procedure could be successfully applied for the analysis of water samples with satisfactory accuracy.

  15. Determination of Anionic Surfactants Using Atomic Absorption Spectrometry and Anodic Stripping Voltammetry

    Science.gov (United States)

    John, Richard; Lord, Daniel

    1999-09-01

    An experiment has been developed for our undergraduate analytical chemistry course that demonstrates the indirect analysis of anionic surfactants by techniques normally associated with metal ion determination; that is, atomic absorption spectroscopy (AAS) and anodic stripping voltammetry (ASV). The method involves the formation of an extractable complex between the synthetic surfactant anion and the bis(ethylenediamine)diaqua copper(II) cation. This complex is extracted into chloroform and then back-extracted into dilute acid. The resulting Cu(II) ions are determined by AAS and ASV. Students are required to determine the concentration of a pre-prepared "unknown" anionic surfactant solution and to collect and analyze a real sample of their choice. After the two extraction processes, students typically obtain close to 100% analytical recovery. Correlation between student AAS and ASV results is very good, indicating that any errors that occur probably result from their technique (dilutions, extractions, preparation of standards, etc.) rather than from the end analyses. The experiment is a valuable demonstration of the following analytical principles: indirect analysis; compleximetric analysis; liquid-liquid (solvent) extraction; back-extraction (into dilute acid); analytical recovery; and metal ion analysis using flame-AAS and ASV.

  16. High-resolution continuum source electrothermal atomic absorption spectrometry: Linearization of the calibration curves within a broad concentration range

    Energy Technology Data Exchange (ETDEWEB)

    Katskov, Dmitri, E-mail: katskovda@tut.ac.za [Tshwane University of Technology, Chemistry Department, Pretoria 0001 (South Africa); Hlongwane, Miranda [Tshwane University of Technology, Chemistry Department, Pretoria 0001 (South Africa); Heitmann, Uwe [German Aerospace Center, Rose-Luxemburg Str. 2, 10178 Berlin (Germany); Florek, Stefan [ISAS-Leibniz-Institut fuer Analytische Wissenschaften e.V., Albert-Einstein-Str. 9,12489 Berlin (Germany)

    2012-05-15

    The calculation algorithm suggested provides linearization of the calibration curves in high-resolution continuum source electrothermal atomic absorption spectrometry. The algorithm is based on the modification of the function wavelength-integrated absorbance vs. concentration of analyte vapor in the absorption volume. According to the suggested approach, the absorption line is represented by a triangle for low and trapezium for high analyte vapor concentration in the absorption volume. The respective semi-empirical formulas include two linearization parameters, which depend on properties of the absorption line and characteristics of the atomizer and spectrometer. The parameters can be approximately evaluated from the theory and determined in practice from the original broad-range calibration curve. The parameters were found and the proposed calculation algorithm verified in the experiments on direct determination of Ag, Cd, Cu, Fe, Mn and Pb in the solutions within a concentration ranges from 0.15 to 625 {mu}g{center_dot}L{sup -1} using tube, platform tube and filter furnace atomizers. The use of various atomizers, lines, elements and atomization temperatures made possible the simulation of various practical analytical conditions. It was found that the algorithm and optimal linearization parameters made it possible to obtain for each line and atomizer linear approximations of the calibration curves within 3-4 orders of magnitude with correlation coefficients close to 0.999. The algorithm makes possible to employ a single line for the direct element determination over a broad concentration range. The sources of errors and the possibility of a priori theoretical evaluation of the linearization parameters are discussed. - Highlights: Black-Right-Pointing-Pointer New calculation algorithm for HR-CS ET AAS measurements was proposed and applied. Black-Right-Pointing-Pointer The suggested formulas include two parameters to be determined experimentally. Black

  17. Absolute number densities of helium metastable atoms determined by atomic absorption spectroscopy in helium plasma-based discharges used as ambient desorption/ionization sources for mass spectrometry

    Science.gov (United States)

    Reininger, Charlotte; Woodfield, Kellie; Keelor, Joel D.; Kaylor, Adam; Fernández, Facundo M.; Farnsworth, Paul B.

    2014-10-01

    The absolute number densities of helium atoms in the 2s 3S1 metastable state were determined in four plasma-based ambient desorption/ionization sources by atomic absorption spectroscopy. The plasmas included a high-frequency dielectric barrier discharge (HF-DBD), a low temperature plasma (LTP), and two atmospheric-pressure glow discharges, one with AC excitation and the other with DC excitation. Peak densities in the luminous plumes downstream from the discharge capillaries of the HF-DBD and the LTP were 1.39 × 1012 cm- 3 and 0.011 × 1012 cm- 3, respectively. Neither glow discharge produced a visible afterglow, and no metastable atoms were detected downstream from the capillary exits. However, densities of 0.58 × 1012 cm- 3 and 0.97 × 1012 cm- 3 were measured in the interelectrode regions of the AC and DC glow discharges, respectively. Time-resolved measurements of metastable atom densities revealed significant random variations in the timing of pulsed absorption signals with respect to the voltage waveforms applied to the discharges.

  18. Determination of arsenic and cadmium in crude oil by direct sampling graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Jesus, Alexandre de; Zmozinski, Ariane Vanessa [Instituto de Quimica, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves 9500, 91501-970 Porto Alegre, RS (Brazil); Damin, Isabel Cristina Ferreira [Faculdade Dom Bosco de Porto Alegre, 90520-280, Porto Alegre, RS (Brazil); Silva, Marcia Messias, E-mail: mmsilva@iq.ufrgs.br [Instituto de Quimica, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves 9500, 91501-970 Porto Alegre, RS (Brazil); Instituto Nacional de Ciencia e Tecnologia do CNPq, INCT de Energia e Ambiente, Universidade Federal da Bahia, 40170-115 Salvador, BA (Brazil); Vale, Maria Goreti Rodrigues [Instituto de Quimica, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves 9500, 91501-970 Porto Alegre, RS (Brazil); Instituto Nacional de Ciencia e Tecnologia do CNPq, INCT de Energia e Ambiente, Universidade Federal da Bahia, 40170-115 Salvador, BA (Brazil)

    2012-05-15

    In this work, a direct sampling graphite furnace atomic absorption spectrometry method has been developed for the determination of arsenic and cadmium in crude oil samples. The samples were weighed directly on the solid sampling platforms and introduced into the graphite tube for analysis. The chemical modifier used for both analytes was a mixture of 0.1% Pd + 0.06% Mg + 0.06% Triton X-100. Pyrolysis and atomization curves were obtained for both analytes using standards and samples. Calibration curves with aqueous standards could be used for both analytes. The limits of detection obtained were 5.1 {mu}g kg{sup -1} for arsenic and 0.2 {mu}g kg{sup -1} for cadmium, calculated for the maximum amount of sample that can be analyzed (8 mg and 10 mg) for arsenic and cadmium, respectively. Relative standard deviations lower than 20% were obtained. For validation purposes, a calibration curve was constructed with the SRM 1634c and aqueous standards for arsenic and the results obtained for several crude oil samples were in agreement according to paired t-test. The result obtained for the determination of arsenic in the SRM against aqueous standards was also in agreement with the certificate value. As there is no crude oil or similar reference material available with a certified value for cadmium, a digestion in an open vessel under reflux using a 'cold finger' was adopted for validation purposes. The use of paired t-test showed that the results obtained by direct sampling and digestion were in agreement at a 95% confidence level. Recovery tests were carried out with inorganic and organic standards and the results were between 88% and 109%. The proposed method is simple, fast and reliable, being appropriated for routine analysis. - Highlights: Black-Right-Pointing-Pointer A direct sampling GF AAS method to determine As and Cd in crude oil was proposed. Black-Right-Pointing-Pointer The conventional chemical modifier Pd/Mg has been used to stabilize As and Cd. Black

  19. Determination of cadmium and lead in edible oils by electrothermal atomic absorption spectrometry after reverse dispersive liquid-liquid microextraction.

    Science.gov (United States)

    López-García, Ignacio; Vicente-Martínez, Yesica; Hernández-Córdoba, Manuel

    2014-06-01

    The dispersive liquid-liquid microextraction of edible oils with a low volume of an acidic solution in the presence of isopropyl alcohol allows cadmium and lead to be completely separated into the aqueous phase. After centrifugation, the metals are determined by electrothermal atomization atomic absorption spectrometry using a palladium salt for chemical modification in the heating cycle. Using a 10 g oil sample, the enrichment factor is 140, which permits detection limits of 0.6 and 10 ng kg(-1) for cadmium and lead, respectively. The results agree with those obtained after sample mineralization. Data for the cadmium and lead levels for 15 samples of different characteristics are given.

  20. Determination of mercury in phosphate fertilizers by cold vapor atomic absorption spectrometry.

    Science.gov (United States)

    de Jesus, Robson M; Silva, Laiana O B; Castro, Jacira T; de Azevedo Neto, Andre D; de Jesus, Raildo M; Ferreira, Sergio L C

    2013-03-15

    In this paper, a method for the determination of mercury in phosphate fertilizers using slurry sampling and cold vapor atomic absorption spectrometry (CV QT AAS) is proposed. Because mercury (II) ions form strong complexes with phosphor compounds, the formation of metallic mercury vapor requires the presence of lanthanum chloride as a release agent. Thiourea increases the amount of mercury that is extracted from the solid sample to the liquid phase of the slurry. The method is established using two steps. First, the slurry is prepared using the sample, lanthanum chloride, hydrochloric acid solution and thiourea solution and is sonicated for 20 min. Afterward, mercury vapor is generated using an aliquot of the slurry in the presence of the hydrochloric acid solution and isoamylic alcohol with sodium tetrahydroborate solution as the reducing agent. The experimental conditions for slurry preparation were optimized using two-level full factorial design involving the factors: thiourea and lanthanum chloride concentrations and the duration of sonication. The method allows the determination of mercury by external calibration using aqueous standards with limits of detection and quantification of 2.4 and 8.2 μg kg(-1), respectively, and precision, expressed as relative standard deviation, of 6.36 and 5.81% for two phosphate fertilizer samples with mercury concentrations of 0.24 and 0.57 mg kg(-1), respectively. The accuracy was confirmed by the analysis of a certified reference material of phosphate fertilizer that was provided by the National Institute of Standards & Technology (NIST). The method was applied to determine mercury in six commercial samples of phosphate fertilizers. The mercury content varied from 33.97 to 209.28 μg kg(-1). These samples were also analyzed employing inductively coupled plasma mass spectrometry (ICP-MS). The ICP-MS results were consistent with the results from our proposed method.

  1. Atomic absorption techniques for determining vanadium and nickel in crude oil

    Energy Technology Data Exchange (ETDEWEB)

    Grizzle, P.L.; Wilson, C.A.; Ferrero, E.P.; Coleman, H.J.

    1977-05-01

    Four different techniques for sample preparation were evaluated for determining vanadium and nickel in crude oils by atomic absorption (AA) spectroscopy: (1) The flame-analyzed dilution method which consists of direct-flame AA analysis after diluting the sample with a suitable organic solvent; (2) the flame-analyzed, wet-ashing method in which the sample is combusted and the residue is then dissolved before flame analysis; (3) the flameless, dilution method which involves flameless AA analysis of the sample following dilution with a suitable organic solvent; and (4) the direct, flameless method in which the crude oil or residue is directly analyzed by flameless AA. The flame-analyzed dilution method yielded erratic and inaccurate analytical results for samples of crude oils as well as for a residual sample containing standard amounts of vanadium and nickel; hence, it is unsatisfactory for oil-identification. Similarly, the direct, flameless method is unsatisfactory owing to the small concentration range available for analysis (less than approximately 15 ppM). Both the flame-analyzed, wet-ashing and flameless-dilution methods yield reliable and reproducible (better than 10%) quantitative data for nickel and vanadium in crude oils and crude oil residues. Results demonstrate that the error associated with the loss of volatile metal containing compounds upon wet-ashing is within the reproducibility of the technique. Although wet-ashing may be slightly more reproducible, the flameless-dilution method is much simpler and faster and is recommended as the better of the two procedures for routine determinations of trace metals for oil identification.

  2. Determination of copper in powdered chocolate samples by slurry-sampling flame atomic-absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Walter N.L. dos; Silva, Erik G.P. da; Fernandes, Marcelo S.; Araujo, Rennan G.O.; Costa, Anto' ' enio C.S.; Ferreira, Sergio L.C. [Nucleo de Excelencia em Quimica Analitica da Bahia, Universidade Federal da Bahia, Instituto de Quimica, Salvador, Bahia (Brazil); Vale, M.G.R. [Instituto de Quimica, Universidade Federal da Bahia do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul (Brazil)

    2005-06-01

    Chocolate is a complex sample with a high content of organic compounds and its analysis generally involves digestion procedures that might include the risk of losses and/or contamination. The determination of copper in chocolate is important because copper compounds are extensively used as fungicides in the farming of cocoa. In this paper, a slurry-sampling flame atomic-absorption spectrometric method is proposed for determination of copper in powdered chocolate samples. Optimization was carried out using univariate methodology involving the variables nature and concentration of the acid solution for slurry preparation, sonication time, and sample mass. The recommended conditions include a sample mass of 0.2 g, 2.0 mol L{sup -1} hydrochloric acid solution, and a sonication time of 15 min. The calibration curve was prepared using aqueous copper standards in 2.0 mol L{sup -1} hydrochloric acid. This method allowed determination of copper in chocolate with a detection limit of 0.4 {mu}g g{sup -1} and precision, expressed as relative standard deviation (RSD), of 2.5% (n=10) for a copper content of approximately 30 {mu}g g{sup -1}, using a chocolate mass of 0.2 g. The accuracy was confirmed by analyzing the certified reference materials NIST SRM 1568a rice flour and NIES CRM 10-b rice flour. The proposed method was used for determination of copper in three powdered chocolate samples, the copper content of which varied between 26.6 and 31.5 {mu}g g{sup -1}. The results showed no significant differences with those obtained after complete digestion, using a t-test for comparison. (orig.)

  3. Determination of Inorganic Arsenic Species by Electrochemical Hydride Generation Atomic Absorption Spectrometry with Selective Electrochemical Reduction

    Institute of Scientific and Technical Information of China (English)

    LI Xun; WANG Zheng-Hao

    2007-01-01

    A new direct procedure for the determination of inorganic arsenic species was developed by electrochemical hydride generation atomic absorption spectrometry (EcHG-AAS) with selective electrochemical reduction. The determination of inorganic arsenic species is based on the fact that As(Ⅲ) shows significantly higher absorbance at low electrolytic currents than As(Ⅴ) in 0.3 mol·L-1 H2SO4.The electrolytic current used for the determination of As(Ⅲ) without considerable interferences of As(V) was 0.4 A, whereas the current for the determination of As(Ⅲ)and As(V) was 1.2 A. For equal concentrations of As(Ⅲ) and As(V) in a sample, the interferences of As(V) during the As(Ⅲ) determination were smaller than 5%. The absorbance for As(V) could be calculated by subtracting that for As(Ⅲ) measured at 0.4 A from the total absorbance for As(Ⅲ) and As(V) measured at 1.2 A, and then the concentration of As(V) can be obtained by its calibration curve at 1.2 A. The methodology developed provided the detection limits of 0.3 and 0.6 ng·ml-1 for As(Ⅲ) and As(V) respectively.The relative standrad deviations were of 3.5% for 20 ng·ml-1 As(Ⅲ) and 302% for 20 ng·ml-1 As(V).The method was successfully applied to determination of soluble inorganic arsenic species in Chinese medicine.

  4. Simple analysis of total mercury and methylmercury in seafood using heating vaporization atomic absorption spectrometry.

    Science.gov (United States)

    Yoshimoto, Keisuke; Anh, Hoang Thi Van; Yamamoto, Atsushi; Koriyama, Chihaya; Ishibashi, Yasuhiro; Tabata, Masaaki; Nakano, Atsuhiro; Yamamoto, Megumi

    2016-01-01

    This study aimed to develop a simpler method for determining total mercury (T-Hg) and methylmercury (MeHg) in biological samples by using methyl isobutyl ketone (MIBK) in the degreasing step. The fat in the samples was extracted by MIBK to the upper phase. T-Hg transferred into the water phase. This was followed by the extraction of MeHg from the water phase using HBr, CuCl2 and toluene. The MeHg fraction was reverse-extracted into L-cysteine-sodium acetate solution from toluene. The concentrations of T-Hg and MeHg were determined by heating vaporization atomic absorption spectrometry. Certified reference materials for T-Hg and MeHg in hair and fish were accurately measured using this method. This method was then applied to determine T-Hg and MeHg concentrations in the muscle, liver and gonads of seafood for the risk assessment of MeHg exposure. The mean T-Hg and MeHg concentrations in squid eggs were 0.023 and 0.022 µg/g, and in squid nidamental glands 0.052 and 0.049 µg/g, respectively. The MeHg/T-Hg ratios in the eggs and nidamental glands of squid were 94.4% and 96.5%, respectively. The mean T-Hg and MeHg concentrations in the gonads of sea urchins were 0.043 and 0.001 µg/g, respectively, with a MeHg/T-Hg ratio of 3.5%. We developed an efficient analytical method for T-Hg and MeHg using MIBK in the degreasing step. The new information on MeHg concentration and MeHg/T-Hg ratios in the egg or nidamental glands of squid and gonads of sea urchin will also be useful for risk assessment of mercury in seafood.

  5. PRECONCENTRATION OF CADMIUM USING AMBERLITE XAD-4 PRIOR TO ATOMIC ABSORPTION SPECTROMETERY

    Directory of Open Access Journals (Sweden)

    S. J. Shahtaheri, M. Khadem, F. Golbabaei, A. Rahimi Froushani

    2006-01-01

    Full Text Available Cadmium is an important environmental constituent widely used in industrial processes for production of synthetic materials and therefore can be released in the environment causing public exposure especially around the industrial residence area. For evaluation of human exposure to trace toxic metal of Cd (II, environmental and biological monitoring are essential processes, in which, preparation of such samples is one of the most time-consuming and error-prone aspects prior to analysis. The use of solid-phase extraction (SPE has grown and is a fertile technique of sample preparation as it provides better results than those produced by liquid-liquid extraction (LLE. To evaluate factors influencing quantitative analysis scheme of cadmium in water samples, solid phase extraction using mini columns filled with XAD-4 resin was optimized with regard to sample pH, ligand concentration, loading flow rate, elution solvent, sample volume (up to 500 ml, elution volume, amount of resins, and sample matrix interferences. Cadmium was retained on solid sorbent and eluted followed by simple determination of analytes by using flame atomic absorption spectrometery. Obtained recoveries of the metal ion were more than 92%. The amount of the analyte detected after simultaneous preconcentration was basically in agreement with the added amounts. The optimized procedure was also validated with three different pools of spiked urine samples and showed a good reproducibility over six consecutive days as well as six within-day experiments. The developed method promised to be applicable for evaluation of other metal ions present in different environmental and occupational samples as suitable results were obtained for relative standard deviation (less than 10%; therefore, it is concluded that, this optimized method can be considered to be successful in simplifying sample preparation for trace residue analysis of Cd in different matrices for evaluation of occupational and

  6. Chemical modifiers in arsenic determination in biological materials by tungsten coil electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Bruhn, C.G.; Huerta, V.N.; Neira, J.Y. [Departamento de Analisis Instrumental, Facultad de Farmacia, Universidad de Concepcion, P.O. Box 237, Concepcion (Chile)

    2004-01-01

    Palladium, iridium, and rhodium are evaluated as possible chemical modifiers in the determination of As in digest solutions of biological materials (human hair and clam) by tungsten coil electrothermal atomic absorption spectrophotometry (TCA-AAS). The modifier in solution was applied onto the coil and thermally pre-reduced; the pre-reduction conditions, the amount of modifier, and the thermal program were optimized. Palladium was not satisfactory, whereas Ir and Rh were effective modifiers and rendered better relative sensitivity for As by a factor of 1.4 and 1.9, respectively compared to the case without modifier. Upon optimization of thermal conditions for As in pre-reduced Ir (2.0 {mu}g) and Rh (2.0 {mu}g) modifiers and in the digest solutions of the study matrices, Rh (2.0 {mu}g) was more effective modifier and was selected as such. The mean within-day repeatability was 2.8% in consecutive measurements (25-100 {mu}g L{sup -1}) (3 cycles, each of n=6) and confirmed good short-term stability of the absorbance measurements. The mean reproducibility was 4.4% (n=20 in a 3-day period) and the detection limit (3{sigma}{sub blank}/slope) was 29 pg (n=15). The useful coil lifetime in Rh modifier was extended to 300-400 firings. Validation was by determination of As in the certified reference material (CRM) of ''Oyster tissue'' solution with a percentage relative error (E{sub rel}%) of 2% and percentage relative standard deviation (RSD%) of 3% (n=4), and by analytical recovery of As spiked in CRM of human hair [94{+-}8% (n=4)]. The methodology is simple, fast (sample readout frequency 21 h{sup -1}), reliable, of low cost, and was applied to the determination of As in hair samples of exposed and unexposed workers. (orig.)

  7. Preparation of Modified Magnetic Nano-Fe3O4 Chitosan/ Graphene Oxide for the Preconcentration and Determination of Copper (П Ions in Biological and Environmental Water Samples Prior to Flame Atomic Absorption Spectrometry.

    Directory of Open Access Journals (Sweden)

    Mohammd Yari

    2016-06-01

    Full Text Available A simple, highly sensitive, accurate and selective method for determination of trace amounts of Cu2+in water samples .In this paper, chitosan grafted with graphene oxide sheets showed an increased surface area was used to encapsulate nano-Fe3O4 and produce a nano-Fe3O4-encapsulated-chitosan/graphene oxide sorbent based new sorbent was prepared. Flame atomic absorption spectrometer was utilized for determination of Cu2+.Some of the important parameters on the preconcentration and complex formation were selected and optimized. Under the optimized conditions the limit of detection (LOD and limit of quantification (LOQwere 0.30,0.750 and the proposed method has a good reproducibility 0.90% (RSD %.The enrichment factor was 200 and the percentage of recovery was in the range of 95-100% .The method was successfully applied to the recovery of Cu2+in different type of water samples. Graphene oxide and its derivates such as magnetic nano-Fe3O4-encapsulated-chitosan/graphene oxide in this study is full of potential to use as an excellent adsorbent in the extraction method like solid phase extraction(SPE and solid phase micro extraction(SPME. In the present study, we report the application of pre concentration techniques still continues increasingly for trace metal determinations by flame atomic absorption spectrometry (FAAS for quantification of Cu2+ in Formalin-fixed paraffin-embedded (FFPE tissues from Liver loggerhead turtles. This method exhibits the superiority in compared to the other adsorption reagents because of the fact that there is no necessity of any complexing reagent and optimum pH of solution presents in acidic media.

  8. Effects of spontaneously induced coherence on absorption of a ladder-type atom

    Institute of Scientific and Technical Information of China (English)

    Ma Hong-Mei; Gong Shang-Qing; Sun Zhen-Rong; Li Ru-Xin; Xu Zhi-Zhan

    2006-01-01

    This paper investigates the effects of spontaneously induced coherence on absorption properties in a nearly equispaced three-level ladder-type system driven by two coherent fields. It find that the absorption properties of this system with the probe field applied on the lower transition can be significantly modified if this coherence is optimized. In the case of small spontaneous decay rate in the upper excited state, it finds that such coherence does not destroy the electromagnetically induced transparency (EIT). Nevertheless, the absorption peak on both sides of zero detuning and the linewidth of absorption line become larger and narrower than those in the case corresponding to the effects of spontaneously induced coherence; while in the case of large decay rate, it finds that, instead of EIT with low resonant absorption, a sharp absorption peak at resonance appears. That is, electromagnetically induced absorption in the nearly equispaced ladder-type system can occur due to such coherent effects.

  9. Identifying student and teacher difficulties in interpreting atomic spectra using a quantum model of emission and absorption of radiation

    Science.gov (United States)

    Savall-Alemany, Francisco; Domènech-Blanco, Josep Lluís; Guisasola, Jenaro; Martínez-Torregrosa, Joaquín

    2016-06-01

    Our study sets out to identify the difficulties that high school students, teachers, and university students encounter when trying to explain atomic spectra. To do so, we identify the key concepts that any quantum model for the emission and absorption of electromagnetic radiation must include to account for the gas spectra and we then design two questionnaires, one for teachers and the other for students. By analyzing the responses, we conclude that (i) teachers lack a quantum model for the emission and absorption of electromagnetic radiation capable of explaining the spectra, (ii) teachers and students share the same difficulties, and (iii) these difficulties concern the model of the atom, the model of radiation, and the model of the interaction between them.

  10. Matrix effects on the determination of manganese in geological materials by atomic-absorption spectrophotometry under different flame conditions

    Science.gov (United States)

    Sanzolone, R.F.; Chao, T.T.

    1978-01-01

    Suppression caused by five of the seven matrix elements studied (Si, Al, Fe, Ca and Mg) was observed in the atomic-absorption determination of manganese in geological materials, when synthetic solutions and the recommended oxidizing air-acetylene flame were used. The magnitude of the suppression effects depends on (1) the kind and concentration of the interfering elements, (2) the type of acid medium, and (3) the concentration of manganese to be determined. All interferences noted are removed or alleviated by using a reducing nitrous oxide-acetylene flame. The atomic-absorption method using this flame can be applied to the determination of total and extractable manganese in a wide range of geological materials without interferences. Analyses of six U.S. Geological Survey rock standards for manganese gave results in agreement with the reported values. ?? 1978.

  11. Role of strongly modulated coherence in transient evolution dynamics of probe absorption in a three-level atomic system

    Science.gov (United States)

    Panchadhyayee, Pradipta

    2013-11-01

    We investigate the dynamical behaviour of atomic response in a closed three-level V-type atomic system with the variation of different relevant parameters to exhibit transient evolution of absorption, gain and transparency in the probe response. The oscillations in probe absorption and gain can be efficiently modulated by changing the values of the Rabi frequency, detuning and the collective phase involved in the system. The interesting outcome of the work is the generation of coherence controlled loop-structure with varying amplitudes in the oscillatory probe response of the probe field at various parameter conditions. The prominence of these structures is observed when the coherence induced in a one-photon excitation path is strongly modified by two-step excitations driven by the coherent fields operating in closed interaction contour. In contrast to purely resonant case, the time interval between two successive loops gets significantly reduced with the application of non-zero detuning in the coherent fields.

  12. Metastable argon atom density in complex argon/acetylene plasmas determined by means of optical absorption and emission spectroscopy

    Science.gov (United States)

    Sushkov, Vladimir; Herrendorf, Ann-Pierra; Hippler, Rainer

    2016-10-01

    Optical emission and absorption spectroscopy has been utilized to investigate the instability of acetylene-containing dusty plasmas induced by growing nano-particles. The density of Ar(1s5) metastable atoms was derived by two methods: tunable diode laser absorption spectroscopy and with the help of the branching ratio method of emitted spectral lines. Results of the two techniques agree well with each other. The density of Ar(1s3) metastable atoms was also measured by means of optical emission spectroscopy. The observed growth instability leads to pronounced temporal variations of the metastable and other excited state densities. An analysis of optical line ratios provides evidence for a depletion of free electrons during the growth cycle but no indication for electron temperature variations.

  13. Arsenic in marine tissues — The challenging problems to electrothermal and hydride generation atomic absorption spectrometry

    Science.gov (United States)

    Karadjova, Irina B.; Petrov, Panayot K.; Serafimovski, Ivan; Stafilov, Trajče; Tsalev, Dimiter L.

    2007-03-01

    Analytical problems in determination of arsenic in marine tissues are addressed. Procedures for the determination of total As in solubilized or extracted tissues with tetramethylammonium hydroxide and methanol have been elaborated. Several typical lyophilized tissues were used: NIST SRM 1566a 'Oyster Tissue', BCR-60 CRM 'Trace Elements in an Aquatic Plant ( Lagarosiphon major)', BCR-627 'Forms of As in Tuna Fish Tissue', IAEA-140/TM 'Sea Plant Homogenate', NRCC DOLT-1 'Dogfish Liver' and two representatives of the Black Sea biota, Mediterranean mussel ( Mytilus galloprovincialis) and Brown algae ( Cystoseira barbata). Tissues (nominal 0.3 g) were extracted in tetramethylammonium hydroxide (TMAH) 1 ml of 25% m/v TMAH and 2 ml of water) or 5 ml of aqueous 80% v/v methanol (MeOH) in closed vessels in a microwave oven at 50 °C for 30 min. Arsenic in solubilized or extracted tissues was determined by electrothermal atomic absorption spectrometry (ETAAS) after appropriate dilution (nominally to 25 ml, with further dilution as required) under optimal instrumental parameters (pyrolysis temperature 900 °C and atomization temperature 2100 °C) with 1.5 μg Pd as modifier on Zr-Ir treated platform. Platforms have been pre-treated with 2.7 μmol of zirconium and then with 0.10 μmol of iridium which served as a permanent chemical modifier in direct ETAAS measurements and as an efficient hydride sequestration medium in flow injection hydride generation (FI-HG)-ETAAS. TMAH and methanol extract 96-108% and 51-100% of As from CRMs. Various calibration approaches have been considered and critically evaluated. The effect of species-dependent slope of calibration graph or standard additions plot for total As determination in a sample comprising of several individual As species with different ETAAS behavior has been considered as a kind of 'intrinsic element speciation interference' that cannot be completely overcome by standard additions technique. Calibration by means of CRMs has

  14. Arsenic in marine tissues - The challenging problems to electrothermal and hydride generation atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Karadjova, Irina B.; Petrov, Panayot K. [Faculty of Chemistry, University of Sofia, 1 James Bourchier Blvd., Sofia 1164 (Bulgaria); Serafimovski, Ivan [Food Institute, Faculty of Veterinary Medicine, Sts. Cyril and Methodius University, P.O. Box 95, MK-1000, Skopje (Macedonia, The Former Yugoslav Republic of); Stafilov, Trajce [Institute of Chemistry, Faculty of Science, Sts. Cyril and Methodius University, P.O. Box 162, MK-1000, Skopje (Macedonia, The Former Yugoslav Republic of); Tsalev, Dimiter L. [Faculty of Chemistry, University of Sofia, 1 James Bourchier Blvd., Sofia 1164 (Bulgaria)], E-mail: tsalev@chem.uni-sofia.bg

    2007-03-15

    Analytical problems in determination of arsenic in marine tissues are addressed. Procedures for the determination of total As in solubilized or extracted tissues with tetramethylammonium hydroxide and methanol have been elaborated. Several typical lyophilized tissues were used: NIST SRM 1566a 'Oyster Tissue', BCR-60 CRM 'Trace Elements in an Aquatic Plant (Lagarosiphon major)', BCR-627 'Forms of As in Tuna Fish Tissue', IAEA-140/TM 'Sea Plant Homogenate', NRCC DOLT-1 'Dogfish Liver' and two representatives of the Black Sea biota, Mediterranean mussel (Mytilus galloprovincialis) and Brown algae (Cystoseira barbata). Tissues (nominal 0.3 g) were extracted in tetramethylammonium hydroxide (TMAH) 1 ml of 25% m/v TMAH and 2 ml of water) or 5 ml of aqueous 80% v/v methanol (MeOH) in closed vessels in a microwave oven at 50 deg. C for 30 min. Arsenic in solubilized or extracted tissues was determined by electrothermal atomic absorption spectrometry (ETAAS) after appropriate dilution (nominally to 25 ml, with further dilution as required) under optimal instrumental parameters (pyrolysis temperature 900 deg. C and atomization temperature 2100 deg. C) with 1.5 {mu}g Pd as modifier on Zr-Ir treated platform. Platforms have been pre-treated with 2.7 {mu}mol of zirconium and then with 0.10 {mu}mol of iridium which served as a permanent chemical modifier in direct ETAAS measurements and as an efficient hydride sequestration medium in flow injection hydride generation (FI-HG)-ETAAS. TMAH and methanol extract 96-108% and 51-100% of As from CRMs. Various calibration approaches have been considered and critically evaluated. The effect of species-dependent slope of calibration graph or standard additions plot for total As determination in a sample comprising of several individual As species with different ETAAS behavior has been considered as a kind of 'intrinsic element speciation interference' that cannot be completely

  15. Determination of As, Cd, Cu, Hg and Pb in biological samples by modern electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Sardans, Jordi, E-mail: j.sardans@creaf.uab.ca [Ecophysiological and Global Change Unit CSIC-CREAF, Edifici C, Universitat Autonoma de Barcelona, Bellaterra 08193, Barcelona (Spain); Montes, Fernando [Departamento de Ciencias Analiticas, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia (UNED), C/ Senda del Rey 9. 28040 Madrid (Spain); Penuelas, Josep [Ecophysiological and Global Change Unit CSIC-CREAF, Edifici C, Universitat Autonoma de Barcelona, Bellaterra 08193, Barcelona (Spain)

    2010-02-15

    Pollution from heavy metals has increased in recent decades and has become an important concern for environmental agencies. Arsenic, cadmium, copper, mercury and lead are among the trace elements that have the greatest impact and carry the highest risk to human health. Electrothermal atomic absorption spectrometry (ETAAS) has long been used for trace element analyses and over the past few years, the main constraints of atomic absorption spectrometry (AAS) methods, namely matrix interferences that provoked high background absorption and interferences, have been reduced. The use of new, more efficient modifiers and in situ trapping methods for stabilization and pre-concentration of these analytes, progress in control of atomization temperatures, new designs of atomizers and advances in methods to correct background spectral interferences have permitted an improvement in sensitivity, an increase in detection power, reduction in sample manipulation, and increase in the reproducibility of the results. These advances have enhanced the utility of Electrothermal atomic absorption spectrometry (ETAAS) for trace element determination at mug L{sup -1} levels, especially in difficult matrices, giving rise to greater reproducibility, lower economic cost and ease of sample pre-treatment compared to other methods. Moreover, the recent introduction of high resolution continuum source Electrothermal atomic absorption spectrometry (HR-CS-ETAAS) has facilitated direct solid sampling, reducing background noise and opening the possibility of achieving even more rapid quantitation of some elements. The incorporation of flow injection analysis (FIA) systems for automation of sample pre-treatment, as well as chemical vapor generation renders (ETAAS) into a feasible option for detection of As and Hg in environmental and food control studies wherein large numbers of samples can be rapidly analyzed. A relatively inexpensive approach with low sample consumption provide additional advantages

  16. Determination of the total iron content of used lubricating oils by atomic-absorption with use of emulsions.

    Science.gov (United States)

    Salvador, A; de la Guardia, M; Berenguer, V

    1983-12-01

    A new method is proposed for the determination of the total iron content of used lubricating oils. It is based on treatment of the samples with a mixture of hydrofluoric and nitric acids (without destruction of the organic matter) and emulsification, followed by atomic-absorption measurement. This allows the use of aqueous standards and provides a simple, rapid, inexpensive and accurate method, that is not affected by the particle size of the solids in the oil.

  17. Determination of Mercury in an Assortment of Dietary Supplements Using an Inexpensive Combustion Atomic Absorption Spectrometry Technique

    OpenAIRE

    Levine, Keith E.; Levine, Michael A.; Weber, Frank X.; Hu, Ye; Perlmutter, Jason; Grohse, Peter M.

    2005-01-01

    The concentrations of mercury in forty, commercially available dietary supplements, were determined using a new, inexpensive analysis technique. The method involves thermal decomposition, amalgamation, and detection of mercury by atomic absorption spectrometry with an analysis time of approximately six minutes per sample. The primary cost savings from this approach is that labor-intensive sample digestion is not required prior to analysis, further automating the analytical procedure. As a res...

  18. Computer programs in BASIC language for atomic absorption flame spectroscopy. Part 2. Documentation. [SEMIAUTOMATIC, RANDOM, and BRACKET codes

    Energy Technology Data Exchange (ETDEWEB)

    Boyle, W.G. Jr.

    1977-10-28

    There are three computer programs, written in the BASIC language, used for taking data from an atomic absorption spectrophotometer operating in the flame mode. The programs are divided into logical sections, and these have been flow-charted. The general features, the structure, the order of subroutines and functions, and the storage of data are discussed. In addition, variables are listed and defined, and a complete listing of each program with a symbol occurrence table is provided.

  19. Nonlinear Absorption-Gain Response and Population Dynamics in a Laser-Driven Four-Level Dense Atomic System

    Institute of Scientific and Technical Information of China (English)

    LI Jia-Hua; LIU Ji-Bing; LUO Jin-Ming; XIE Xiao-Tao

    2006-01-01

    We theoretically investigate the response of nonlinear absorption and population dynamics in optically dense media of four-level atoms driven by a single-mode probe laser, via taking the density-dependent near dipoledipole (NDD) interactions into consideration. The influence of the NDD effects on the absorption of the probe field and population dynamics is predicted via numerical calculations. It is shown that the NDD effects can reduce gradually to transient absorption with the increase of the strengths of the NDD interactions, and transient amplification can be achieved. In the steady-state limit, the probe field exhibits transparency for strong NDD interactions. Alternatively, the population entirely remains at the ground state due to the NDD effects.

  20. Absorption and Recurrence Spectra of Nonhydrogenic Rydberg Atom Near a Metal Surface

    Institute of Scientific and Technical Information of China (English)

    ZHOU Jun; WANG De-Hua; XUE Chun-Hua; QI Yi-Hong; LOU Sen-Yue

    2008-01-01

    Multielectron atoms near a metal surface are essentially more complicated than hydrogen atom with regard to theoretical treatments. By using the semicalssical closed orbit theory generalized to the multielecton atoms, we study the dynamical properties of the Rydberg lithium atom near a metal surface. The photoabsorption spectra and recurrence spectra of this system have also been calculated. Considering the effect of the ionic core potential of the Rydberg lithium atom, the number of the closed orbits increases, which leads to more peaks in the recurrence spectra than the case of hydrogen atom near a metal surface. This result shows that the core-scattered effects play an important role in nonhydrogenic atoms. This study is a new application of the dosed-orbit theory and is of potential experimental interest.

  1. Use of Doehlert and constrained mixture designs in the development of a photo-oxidation procedure using UV radiation/H₂O₂ for decomposition of landfill leachate samples and determination of metals by flame atomic absorption spectrometry.

    Science.gov (United States)

    Bezerra, Marcos A; Souza, Antônio D S; Oliveira, Rafael V; Oliveira, Djalma M; Cardoso, Luiz A M; Sousa Filho, Hélio R

    2015-03-01

    This work proposes the use of photo-oxidation degradation with UV radiation/H2O2 as sample treatment for the determination of Fe, Zn, Mn, Ni and Co in municipal solid waste landfill leachate by flame atomic absorption spectrometry (FAAS). Three variables (pH, irradiation time and buffer concentration) were optimized using Doehlert design and the proportions of mixture components submitted to UV radiation (leachate sample, buffer solution and H2O2 30%, v/v) were optimized using a constrained mixture design. Using the experimental conditions established, this procedure allows limits of detection of 0.075, 0.025, 0.010, 0.075 and 0.041 µg mL-1, and the precision levels expressed as relative standard (%RSD, 0.5 µg mL-1) were 3.6, 1.8, 1.3, 3.3 and 1.7%, for Fe, Mn, Zn, Ni and Co respectively. Recovery tests were carried out for evaluation of the procedure accuracy and recoveries were between 92 and 106% for the studied metals. This procedure has been applied for the analysis of the landfill leachate collected in Jequié, a city of the southwestern region of the State of Bahia, Brazil. The results were compared with those obtained by acid digestion. There was no significant difference between the results obtained by the two methods based on paired t-test at 95% confidence level.

  2. Nano-level determination of copper with atomic absorption spectrometry after pre-concentration on N,N-(4-methyl-1,2-phenylene)diquinoline-2-carboxamide-naphthalene

    Energy Technology Data Exchange (ETDEWEB)

    Rezaei, Behzad, E-mail: rezaei@cc.iut.ac.ir [Department of Chemistry, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Sadeghi, Elham; Meghdadi, Soraia [Department of Chemistry, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of)

    2009-09-15

    A novel, simple, sensitive and effective method has been developed for selective extraction and pre-concentration of copper on N,N-(4-methyl-1,2-phenylene)diquinoline-2-carboxamide-naphthalene. After pre-concentration, copper was eluted from sorbent with hydrochloric acid, and then flame atomic absorption spectrometry (FAAS) was used for its determination. The effect of pH, sample flow rate and the volume and concentration of eluent on the recovery of the analyte was investigated and the optimum conditions were established. A pre-concentration factor of 400, and an adsorption capacity of 6.9 mg g{sup -1} of the solid-phase sorbent or 82.8 mg g{sup -1} of ligand was achieved using the optimum conditions. The calibration graph was linear in the range of 1.0-4000 ng mL{sup -1} with the detection limit of 1.0 ng mL{sup -1}. A R.S.D. value of 2.4% was obtained by this method for 400 ng mL{sup -1} of Cu{sup 2+} solution. This procedure has been successfully applied to separate and determine the ultra trace levels of copper in the environmental samples, free from the interference of some diverse ions.

  3. Preconcentration of Pb(II), Cr(III), Cu(II), Ni(II) and Cd(II) ions in environmental samples by membrane filtration prior to their flame atomic absorption spectrometric determinations

    Energy Technology Data Exchange (ETDEWEB)

    Divrikli, Umit [Pamukkale University, Faculty of Arts and Science, Department of Chemistry, 20020 Denizli (Turkey)]. E-mail: udivrikli@pamukkale.edu.tr; Kartal, Aslihan Arslan [Pamukkale University, Faculty of Arts and Science, Department of Chemistry, 20020 Denizli (Turkey); Soylak, Mustafa [Erciyes University, Faculty of Arts and Science, Department of Chemistry, 38039 Kayseri (Turkey); Elci, Latif [Pamukkale University, Faculty of Arts and Science, Department of Chemistry, 20020 Denizli (Turkey)

    2007-07-16

    A method for separation-preconcentration of Pb(II), Cr(III), Cu(II), Ni(II) and Cd(II) ions by membrane filtration has been described. The method based on the collection of analyte metal ions on a cellulose nitrate membrane filter and determination of analytes by flame atomic absorption spectrometry (FAAS). The method was optimized for several parameters including of pH, matrix effects and sample volume. The recoveries of analytes were generally in the range of 93-100%. The detection limits by 3 sigma for analyte ions were 0.02 {mu}g L{sup -1} for Pb(II), 0.3 {mu}g L{sup -1} for Cr(III), 3.1 {mu}g L{sup -1} for Cu(II), 7.8 {mu}g L{sup -1} for Ni(II) and 0.9 {mu}g L{sup -1} for Cd(II). The proposed method was applied to the determination of lead, chromium, copper, nickel and cadmium in tap waters and RM 8704 Buffalo River Sediment standard reference material with satisfactory results. The relative standard deviations of the determinations were below 10%.

  4. A new ultrasonic-assisted cloud-point-extraction procedure for pre-concentration and determination of ultra-trace levels of copper in selected beverages and foods by flame atomic absorption spectrometry.

    Science.gov (United States)

    Altunay, Nail; Gürkan, Ramazan; Orhan, Ulaş

    2015-01-01

    A new ultrasonic-assisted cloud-point-extraction (UA-CPE) method was developed for the pre-concentration of Cu(II) in selected beverage and food samples prior to flame atomic absorption spectrometric (FAAS) analysis. For this purpose, Safranin T was used as an ion-pairing reagent based on charge transfer in the presence of oxalate as the primary chelating agent at pH 10. Non-ionic surfactant, poly(ethyleneglycol-mono-p-nonylphenylether) (PONPE 7.5) was used as an extracting agent in the presence of NH4Cl as the salting out agent. The variables affecting UA-CPE efficiency were optimised in detail. The linear range for Cu(II) at pH 10 was 0.02-70 µg l(-)(1) with a very low detection limit of 6.10 ng l(-)(1), while the linear range for Cu(I) at pH 8.5 was 0.08-125 µg l(-)(1) with a detection limit of 24.4 ng l(-)(1). The relative standard deviation (RSD %) was in the range of 2.15-4.80% (n = 5). The method was successfully applied to the quantification of Cu(II), Cu(I) and total Cu in selected beverage and food samples. The accuracy of the developed method was demonstrated by the analysis of two standard reference materials (SRMs) as well as recoveries of spiked samples.

  5. Vortex-assisted surfactant-enhanced-emulsification liquid-liquid microextraction with solidification of floating organic droplet combined with flame atomic absorption spectrometry for the fast determination of cadmium in water samples.

    Science.gov (United States)

    Peng, Guilong; Lu, Ying; He, Qiang; Mmereki, Daniel; Tang, Xiaohui; Zhong, Zhihui; Zhao, Xiaolong

    2016-01-01

    A novel vortex-assisted surfactant-enhanced-emulsification liquid-liquid microextraction with solidification of floating organic droplet (VSLLME-SFO) was developed for the fast, simple and efficient determination of cadmium (Cd) in water samples followed by flame atomic absorption spectrometry (FAAS). In the VSLLME-SFO process, the addition of surfactant (as an emulsifier), could enhance the mass transfer from the aqueous solution into the extraction solvent. The extraction solvent could be dispersed into the aqueous phase under vigorous shaking with the vortex. In this paper, we investigated the influences of analytical parameters, including pH, extraction solvent type and its volume, surfactant type and its volume, concentration of chelating agent, salt effect and vortex time, on the extraction efficiency of Cd. Under the optimized conditions, the limit of detection was 0.16 μg/L. The analyte enrichment factor was 37.68. The relative standard deviation was 3.2% (10 μg/L, n = 10) and the calibration graph was linear, ranging from 0.5 to 30 μg/L. The proposed method was successfully applied for the analysis of ultra-trace Cd in river water and wastewater samples.

  6. Use of Doehlert and constrained mixture designs in the development of a photo-oxidation procedure using UV radiation/H2O2 for decomposition of landfill leachate samples and determination of metals by flame atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    Marcos A. Bezerra

    2015-03-01

    Full Text Available This work proposes the use of photo-oxidation degradation with UV radiation/H2O2 as sample treatment for the determination of Fe, Zn, Mn, Ni and Co in municipal solid waste landfill leachate by flame atomic absorption spectrometry (FAAS. Three variables (pH, irradiation time and buffer concentration were optimized using Doehlert design and the proportions of mixture components submitted to UV radiation (leachate sample, buffer solution and H2O2 30%, v/v were optimized using a constrained mixture design. Using the experimental conditions established, this procedure allows limits of detection of 0.075, 0.025, 0.010, 0.075 and 0.041 µg mL-1, and the precision levels expressed as relative standard (%RSD, 0.5 µg mL-1 were 3.6, 1.8, 1.3, 3.3 and 1.7%, for Fe, Mn, Zn, Ni and Co respectively. Recovery tests were carried out for evaluation of the procedure accuracy and recoveries were between 92 and 106% for the studied metals. This procedure has been applied for the analysis of the landfill leachate collected in Jequié, a city of the southwestern region of the State of Bahia, Brazil. The results were compared with those obtained by acid digestion. There was no significant difference between the results obtained by the two methods based on paired t-test at 95% confidence level.

  7. Dispersive liquid-liquid microextraction combined with graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Zeini Jahromi, Elham [Department of Analytical Chemistry, Faculty of Chemistry, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Electroanalytical Chemistry Research Center, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Bidari, Araz [Department of Analytical Chemistry, Faculty of Chemistry, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Electroanalytical Chemistry Research Center, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Assadi, Yaghoub [Department of Analytical Chemistry, Faculty of Chemistry, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of) and Electroanalytical Chemistry Research Center, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of)]. E-mail: y_assadi@iust.ac.ir; Milani Hosseini, Mohammad Reza [Department of Analytical Chemistry, Faculty of Chemistry, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Electroanalytical Chemistry Research Center, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Jamali, Mohammad Reza [Department of Analytical Chemistry, Faculty of Chemistry, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Electroanalytical Chemistry Research Center, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of)

    2007-03-07

    Dispersive liquid-liquid microextraction (DLLME) technique was successfully used as a sample preparation method for graphite furnace atomic absorption spectrometry (GF AAS). In this extraction method, 500 {mu}L methanol (disperser solvent) containing 34 {mu}L carbon tetrachloride (extraction solvent) and 0.00010 g ammonium pyrrolidine dithiocarbamate (chelating agent) was rapidly injected by syringe into the water sample containing cadmium ions (interest analyte). Thereby, a cloudy solution formed. The cloudy state resulted from the formation of fine droplets of carbon tetrachloride, which have been dispersed, in bulk aqueous sample. At this stage, cadmium reacts with ammonium pyrrolidine dithiocarbamate, and therefore, hydrophobic complex forms which is extracted into the fine droplets of carbon tetrachloride. After centrifugation (2 min at 5000 rpm), these droplets were sedimented at the bottom of the conical test tube (25 {+-} 1 {mu}L). Then a 20 {mu}L of sedimented phase containing enriched analyte was determined by GF AAS. Some effective parameters on extraction and complex formation, such as extraction and disperser solvent type and their volume, extraction time, salt effect, pH and concentration of the chelating agent have been optimized. Under the optimum conditions, the enrichment factor 125 was obtained from only 5.00 mL of water sample. The calibration graph was linear in the rage of 2-20 ng L{sup -1} with detection limit of 0.6 ng L{sup -1}. The relative standard deviation (R.S.D.s) for ten replicate measurements of 20 ng L{sup -1} of cadmium was 3.5%. The relative recoveries of cadmium in tap, sea and rivers water samples at spiking level of 5 and 10 ng L{sup -1} are 108, 95, 87 and 98%, respectively. The characteristics of the proposed method have been compared with cloud point extraction (CPE), on-line liquid-liquid extraction, single drop microextraction (SDME), on-line solid phase extraction (SPE) and co-precipitation based on bibliographic data

  8. Study of the roles of chemical modifiers in determining boron using graphite furnace atomic absorption spectrometry and optimization of the temperature profile during atomization.

    Science.gov (United States)

    Yamamoto, Yuhei; Shirasaki, Toshihiro; Yonetani, Akira; Imai, Shoji

    2015-01-01

    The measurement conditions for determining boron using graphite furnace-atomic absorption spectrometry (GF-AAS) were investigated. Differences in the boron absorbance profiles were found using three different commercially available GF-AAS instruments when the graphite atomizers in them were not tuned. The boron absorbances found with and without adjusting the graphite atomizers suggested that achieving an adequate absorbance for the determination of boron requires a sharp temperature profile that overshoots the target temperature during the atomization process. Chemical modifiers that could improve the boron absorbance without the need for using coating agents were tested. Calcium carbonate improved the boron absorbance but did not suppress variability in the peak height. Improvement of boron absorbance was comparatively less using iron nitrate or copper nitrate than using calcium carbonate, but variability in the peak height was clearly suppressed using iron nitrate or copper nitrate. The limit of detection was 0.0026 mg L(-1) when iron nitrate was used. It appears that iron nitrate is a useful new chemical modifier for the quick and simple determination of boron using GF-AAS.

  9. Methylmercury determination using a hyphenated high performance liquid chromatography ultraviolet cold vapor multipath atomic absorption spectrometry system

    Science.gov (United States)

    Campos, Reinaldo C.; Gonçalves, Rodrigo A.; Brandão, Geisamanda P.; Azevedo, Marlo S.; Oliveira, Fabiana; Wasserman, Julio

    2009-06-01

    The present work investigates the use of a multipath cell atomic absorption mercury detector for mercury speciation analysis in a hyphenated high performance liquid chromatography assembly. The multipath absorption cell multiplies the optical path while energy losses are compensated by a very intense primary source. Zeeman-effect background correction compensates for non-specific absorption. For the separation step, the mobile phase consisted in a 0.010% m/v mercaptoethanol solution in 5% methanol (pH = 5), a C 18 column was used as stationary phase, and post column treatment was performed by UV irradiation (60 °C, 13 W). The eluate was then merged with 3 mol L - 1 HCl, reduction was performed by a NaBH 4 solution, and the Hg vapor formed was separated at the gas-liquid separator and carried through a desiccant membrane to the detector. The detector was easily attached to the system, since an external gas flow to the gas-liquid separator was provided. A multivariate approach was used to optimize the procedure and peak area was used for measurement. Instrumental limits of detection of 0.05 µg L - 1 were obtained for ionic (Hg 2+) and HgCH 3+, for an injection volume of 200 µL. The multipath atomic absorption spectrometer proved to be a competitive mercury detector in hyphenated systems in relation to the most commonly used atomic fluorescence and inductively coupled plasma mass spectrometric detectors. Preliminary application studies were performed for the determination of methyl mercury in sediments.

  10. Methylmercury determination using a hyphenated high performance liquid chromatography ultraviolet cold vapor multipath atomic absorption spectrometry system

    Energy Technology Data Exchange (ETDEWEB)

    Campos, Reinaldo C. [Department of Chemistry, Pontifical Catholic University of Rio de Janeiro, Rua Marques de S Vicente 225, 22453-900 Rio de Janeiro (Brazil)], E-mail: rccampos@puc-rio.br; Goncalves, Rodrigo A.; Brandao, Geisamanda P.; Azevedo, Marlo S. [Department of Chemistry, Pontifical Catholic University of Rio de Janeiro, Rua Marques de S Vicente 225, 22453-900 Rio de Janeiro (Brazil); Oliveira, Fabiana; Wasserman, Julio [Institut of Geosciences, Fluminense Federal University, Av. Gal. Milton Tavares de Souza, s/n, 24.210-340, Niteroi, Rio de Janeiro (Brazil)

    2009-06-15

    The present work investigates the use of a multipath cell atomic absorption mercury detector for mercury speciation analysis in a hyphenated high performance liquid chromatography assembly. The multipath absorption cell multiplies the optical path while energy losses are compensated by a very intense primary source. Zeeman-effect background correction compensates for non-specific absorption. For the separation step, the mobile phase consisted in a 0.010% m/v mercaptoethanol solution in 5% methanol (pH = 5), a C{sub 18} column was used as stationary phase, and post column treatment was performed by UV irradiation (60 deg. C, 13 W). The eluate was then merged with 3 mol L{sup -1} HCl, reduction was performed by a NaBH{sub 4} solution, and the Hg vapor formed was separated at the gas-liquid separator and carried through a desiccant membrane to the detector. The detector was easily attached to the system, since an external gas flow to the gas-liquid separator was provided. A multivariate approach was used to optimize the procedure and peak area was used for measurement. Instrumental limits of detection of 0.05 {mu}g L{sup -1} were obtained for ionic (Hg{sup 2+}) and HgCH{sub 3}{sup +}, for an injection volume of 200 {mu}L. The multipath atomic absorption spectrometer proved to be a competitive mercury detector in hyphenated systems in relation to the most commonly used atomic fluorescence and inductively coupled plasma mass spectrometric detectors. Preliminary application studies were performed for the determination of methyl mercury in sedi0011men.

  11. Handbook of theoretical atomic physics data for photon absorption, electron scattering, and vacancies decay

    CERN Document Server

    Amusia, Miron Ya; Yarzhemsky, Victor

    2012-01-01

    The aim of this book is to present highly accurate and extensive theoretical Atomic data and to give a survey of selected calculational methods for atomic physics, used to obtain these data. The book presents the results of calculations of cross sections and probabilities of a broad variety of atomic processes with participation of photons and electrons, namely on photoabsorption, electron scattering and accompanying effects. Included are data for photoabsorption and electron scattering cross-sections and probabilities of vacancy decay formed for a large number of atoms and ions. Attention is also given to photoionization and vacancy decay in endohedrals and to positron-atom scattering. The book is richly illustrated. The methods used are one-electron Hartree-Fock and the technique of Feynman diagrams that permits to include many-electron correlations. This is done in the frames of the Random Phase approximation with exchange and the many-body perturbation theory. Newly obtained and previously collected atomi...

  12. Spontaneous absorption of an accelerated hydrogen atom near a conducting plane in vacuum

    CERN Document Server

    Yu, H; Yu, Hongwei; Zhu, Zhiying

    2006-01-01

    We study, in the multipolar coupling scheme, a uniformly accelerated multilevel hydrogen atom in interaction with the quantum electromagnetic field near a conducting boundary and separately calculate the contributions of the vacuum fluctuation and radiation reaction to the rate of change of the mean atomic energy. It is found that the perfect balance between the contributions of vacuum fluctuations and radiation reaction that ensures the stability of ground-state atoms is disturbed, making spontaneous transition of ground-state atoms to excited states possible in vacuum with a conducting boundary. The boundary-induced contribution is effectively a nonthermal correction, which enhances or weakens the nonthermal effect already present in the unbounded case, thus possibly making the effect easier to observe. An interesting feature worth being noted is that the nonthermal corrections may vanish for atoms on some particular trajectories.

  13. Estimation of lead, cadmium and nickel content by means of Atomic Absorption Spectroscopy in dry fruit bodies of some macromycetes growing in Poland. II.

    Directory of Open Access Journals (Sweden)

    Jan Grzybek

    2014-08-01

    Full Text Available The content of lead, cadmium, and nickel in dry fruit bodies of 34 species of macromyoetes collected in Poland from 72 natural babitats by means of Atomic Absorption Spectroscopy (AAS was estimated.

  14. Quantitative estimatation of lead, cadmium. and nickel contents by means of Atomic Absorption Spectroscopy in fruitbodies of some macromycetes in Poland

    Directory of Open Access Journals (Sweden)

    Jan Grzybek

    2014-08-01

    Full Text Available The contents of lead, cadmium and nickel in dry fruitbodies of 13 species of macromycetes collected in Poland from 33 natural habitats by means of Atomic Absorption Spectroscopy (AAS were estimated.

  15. New Homogeneous Standards by Atomic Layer Deposition for Synchrotron X-ray Fluorescence and Absorption Spectroscopies.

    Energy Technology Data Exchange (ETDEWEB)

    Butterworth, A.L.; Becker, N.; Gainsforth, Z.; Lanzirotti, A.; Newville, M.; Proslier, T.; Stodolna, J.; Sutton, S.; Tyliszczak, T.; Westphal, A.J.; Zasadzinski, J. (UCB)

    2012-03-13

    Quantification of synchrotron XRF analyses is typically done through comparisons with measurements on the NIST SRM 1832/1833 thin film standards. Unfortunately, these standards are inhomogeneous on small scales at the tens of percent level. We are synthesizing new homogeneous multilayer standards using the Atomic Layer Deposition technique and characterizing them using multiple analytical methods, including ellipsometry, Rutherford Back Scattering at Evans Analytical, Synchrotron X-ray Fluorescence (SXRF) at Advanced Photon Source (APS) Beamline 13-ID, Synchrotron X-ray Absorption Spectroscopy (XAS) at Advanced Light Source (ALS) Beamlines 11.0.2 and 5.3.2.1 and by electron microscopy techniques. Our motivation for developing much-needed cross-calibration of synchrotron techniques is borne from coordinated analyses of particles captured in the aerogel of the NASA Stardust Interstellar Dust Collector (SIDC). The Stardust Interstellar Dust Preliminary Examination (ISPE) team have characterized three sub-nanogram, {approx}1{micro}m-sized fragments considered as candidates to be the first contemporary interstellar dust ever collected, based on their chemistries and trajectories. The candidates were analyzed in small wedges of aerogel in which they were extracted from the larger collector, using high sensitivity, high spatial resolution >3 keV synchrotron x-ray fluorescence spectroscopy (SXRF) and <2 keV synchrotron x-ray transmission microscopy (STXM) during Stardust ISPE. The ISPE synchrotron techniques have complementary capabilities. Hard X-ray SXRF is sensitive to sub-fg mass of elements Z {ge} 20 (calcium) and has a spatial resolution as low as 90nm. X-ray Diffraction data were collected simultaneously with SXRF data. Soft X-ray STXM at ALS beamline 11.0.2 can detect fg-mass of most elements, including cosmochemically important oxygen, magnesium, aluminum and silicon, which are invisible to SXRF in this application. ALS beamline 11.0.2 has spatial resolution

  16. A comparison of simultaneous plasma, atomic absorption, and iron colorimetric determinations of major and trace constituents in acid mine waters

    Science.gov (United States)

    Ball, J.W.; Nordstrom, D.K.

    1994-01-01

    Sixty-three water samples collected during June to October 1982 from the Leviathan/Bryant Creek drainage basin were originally analyzed by simultaneous multielement direct-current plasma (DCP) atomic-emission spectrometry, flame atomic-absorption spectrometry, graphite-furnace atomic-absorption spectrometry (GFAAS) (thallium only), ultraviolet-visible spectrometry, and hydride-generation atomic-absorption spectrometry.Determinations were made for the following metallic and semi-metallic constituents: AI, As, B, Ba, Be, Bi, Cd, Ca, Cr, Co, Cu, Fe(11), Fe(total), Li, Pb, Mg, Mn, Mo, Ni, K, Sb, Se, Si, Na, Sr, TI, V, and Zn. These samples were re-analyzed later by simultaneous multielement inductively coupled plasma (ICP) atomic-emission spectrometry and Zeeman-corrected GFAAS to determine the concentrations of many of the same constituents with improved accuracy, precision, and sensitivity. The result of this analysis has been the generation of comparative concentration values for a significant subset of the solute constituents. Many of the more recently determined values replace less-than-detection values for the trace metals; others constitute duplicate analyses for the major constituents. The multiple determinations have yielded a more complete, accurate, and precise set of analytical data. They also have resulted in an opportunity to compare the performance of the plasma-emission instruments operated in their respective simultaneous multielement modes. Flame atomic-absorption spectrometry was judged best for Na and K and hydride-generation atomic-absorption spectrometry was judged best for As because of their lower detection limit and relative freedom from interelement spectral effects. Colorimetric determination using ferrozine as the color agent was judged most accurate, precise, and sensitive for Fe. Cadmium, lead, and vanadium concentrations were too low in this set of samples to enable a determination of whether ICP or DCP is a more suitable technique. Of

  17. Absorption and Recurrence Spectra of Sodium Rydberg Atom in a Strong External Magnetic Field

    Institute of Scientific and Technical Information of China (English)

    WANG De-Hua; LIN Sheng-Lu

    2004-01-01

    Using core-scattered closed-orbit theory, we calculate the photoabsorption and the scaled recurrence spectra of sodium Rydberg atom in strong magnetic field below ionization threshold. The non-Coulombic nature of the ionic core have been modified by a model potential, which includes an attractive Coulomb potential and a short-ranged core potential. A family of core-scattered nonhydrogenic closed orbits have also been discovered. The Fourier transformed spectra of sodium atom have allowed direct comparison between peaks in such plot and the scaled action values of closed orbits. The new peaks in the recurrence spectra of sodium atom have been considered as effects caused by the core scattering of returning waves at the ionic core. The results are compared with those of hydrogen case, which show that the core-scattered effects play an important role in alkali-metal atoms.

  18. Absorption and Recurrence Spectra of Sodium Rydberg Atom in a Strong External Magnetic Field

    Institute of Scientific and Technical Information of China (English)

    WANGDe-Hua; LINSheng-Lu

    2004-01-01

    Using core-scattered closed-orbit theory, we calculate the photoabsorption and the scaled recurrence spectra of sodium Rydberg atom in strong magnetic fied below ionization threshoM. The non-Coulombic nature of the ionic core have been modified by a model potential, which includes an attractive Coulomb potential and a short-ranged core potential. A family of core-scattered nonhydrogenic closed orbits have also been discovered. The Fourier transformed spectra of sodium atom have allowed direct comparison between peaks in such plot and the scaled action values of closed orbits. The new peaks in the recurrence spectra of sodium atom have been considered as effects caused by the core scattering of returning waves at the ionic core. The results are compared with those of hydrogen case, which show that the core-scattered effects play an important role in alkali-metal atoms.

  19. Determination of cadmium by electrothermal atomic absorption spectrometry after microwave-assisted digestion of animal tissues and sewage sludges.

    Science.gov (United States)

    Chakraborty, R; Das, A K; Cervera, M L; De La Guardia, M

    1996-04-01

    The determination of cadmium in different sample types has been carried out by electrothermal atomization atomic absorption spectrometry with D(2)-background correction using a unpyrocoated graphite tube, after pressurized microwave-assisted digestion. Five chemical modifiers [(NH(4))(2)HPO(4), Pd(NO)(3))(2), Ni(NO(3))(2), thiourea and Triton X-100] have been assayed and nickel nitrate has been found to be most effective for an accurate determination of cadmium in mussel tissue, pig kidney and sewage sludge. The characteristic mass of the method is of the order of 1 pg and the limit of detection is lower than 0.1 ng/ml.

  20. A New Cross-Shaped Graphite Furnace with Ballast Body for Reduction of Interferences in Atomic Absorption Spectrometry

    Directory of Open Access Journals (Sweden)

    A. A. Asweisi

    2010-01-01

    Full Text Available A new crossed graphite furnace for atomic absorption spectrometry (GFAAS was designed and installed in heated graphite atomizer (HGA500 combined with Perkin-Elmer spectrometer (AAS1100. The Tungsten ballast body was inserted inside one part of the crossed furnace in a way perpendicular to light path. The analyzed sample was injected manually on the ballast body inside the cross and pushed into the measuring zone using the original inner and additional purge gas. The sample was adsorbed strongly on the ballast and evaporated and transferred with different rates at different temperatures during the temperature program allowing the separation of analyte and matrix signals. Analysis of middle volatile element such as copper and manganese in standard urine sample (seronorm 2525 showed complete separation of analyte and background signals with good sensitivity and repeatability.

  1. Microwave-assisted extraction and ultrasonic slurry sampling procedures for cobalt determination in geological samples by electrothermal atomic absorption spectroscopy.

    Science.gov (United States)

    Felipe-Sotelo, M; Carlosena, A; Fernández, E; López-Mahía, P; Muniategui, S; Prada, D

    2004-06-17

    Slurry sampling is compared to microwave-assisted acid digestion for cobalt determination in soil/sediment samples by electrothermal atomic absorption spectrometry (ETAAS). Furnace temperature programs and appropriate amounts of three chemical modifiers were optimised in order to get the highest signals and good separations between the atomic and background signals. Using nitric acid (0.5% (v/v)) as liquid medium, no chemical modifier was needed. The detection limit, based on integrated absorbance, was 0.04mugg(-1) for digests and slurries. Within-batch precision and analytical recoveries were satisfactory for both procedures. Accuracy was tested by analysing a reference soil and a sediment from IRMM. The methods were further compared employing a set of roadside soils and estuarine sediments. As no significant differences (95% confidence) were found, practical analytical properties were suggested in order to select one of them.

  2. An abbreviated fire-assay atomic-absorption method for the determination of gold and silver in ores and concentrates.

    Science.gov (United States)

    Moloughney, P E

    1977-02-01

    A simplified scheme, combining aspects of the classical fire-assay with an atomic-absorption finish, is presented for the determination of gold and silver in ores and concentrates. The lead assay button is scorified to approximately 2 g and then parted in nitric acid. The filtrate is analysed by AAS for silver; the residue is dissolved in aqua regia and subsequently analysed for gold by AAS. The precision and accuracy of the method have been established by application to four diverse certified reference materials. The proposed method eliminates the need for such time-consuming steps as inquartation, multiple scorifications, and cupellation.

  3. [Determination of Pb and Al in blood and hair of child using transverse heated graphite furnace atomic absorption spectroscopy].

    Science.gov (United States)

    Niu, Feng-lan; Xie, Wen-bing; Li, Chen-xu; Dong, Wei-yan

    2005-04-01

    Pb and Al in blood and hair of child were determined by transverse heated graphite furnace atomic absorption spectrometry with NH4H2PO4 and Mg(NO3)2 as a modifier, which enhanced the temperature of ashing, eliminated the matrix interference and memorial effect. The method is rapid, simple and accurate. The characteristic mass of the method was 2.3 x 10(-11) g and 2.2 x 10(-11) g for Pb and Al respectively. The relative standard deviation of Pb and Al was 3.0% and 11.4%, respectively, and the recovery was 96%-102%.

  4. Determination of silver in soils, sediments, and rocks by organic-chelate extraction and atomic absorption spectrophotometry

    Science.gov (United States)

    Chao, T.T.; Ball, J.W.; Nakagawa, H.M.

    1971-01-01

    A useful method for the determination of silver in soil, sediment, and rock samples in geochemical exploration has been developed. The sample is digested with concentrated nitric acid, and the silver extracted with triisooctyl thiophosphate (TOTP) in methyl isobutyl ketone (MIBK) after dilution of the acid digest to approximately 6 M. The extraction of silver into the organic extractant is quantitative and not affected by the nitric acid concentration from 4 M to 8 M, or by different volumes of TOTP-MIBK. The extracted silver is stable and remains in the organic phase up to several days. The silver concentration is determined by atomic absorption spectrophotometry. ?? 1971.

  5. Direct determination of lead in human urine and serum samples by electrothermal atomic absorption spectrometry and permanent modifiers

    OpenAIRE

    Andrada,Daniel; Pinto,Frederico G.; Magalhães, Cristina Gonçalves; Nunes,Berta R.; Franco,Milton B.; Silva,José Bento Borba da

    2006-01-01

    The object of the present study was the development of alternative methods for the direct determination of lead in undigested samples of human urine and serum by electrothermal atomic absorption spectrometry (ET AAS). Thus, some substances have been investigated to act as chemical modifiers. Volumes of 20 µL of diluted samples, 1 + 1, v/v for urine and 1 + 4, v/v for serum, with HNO3 1% v/v and 0.02% v/v of cetil trimethyl ammonium chloride (CTAC) were prepared directly in the autosampler cup...

  6. Arsenic speciation by hydride generation-quartz furnace atomic absorption spectrometry. Optimization of analytical parameters and application to environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Molenat, N.; Astruc, A.; Holeman, M.; Pinel, R. [Laboratoire de Chimie Analytique Bioinorganique et Environnement, Dept. de Chimie, Faculte des Sciences et Techniques, 64 - Pau (France); Maury, G. [Montpellier-2 Univ., 34 (France). Dept. de Chimie Organique Fine

    1999-11-01

    Analytical parameters of hydride generation, trapping, gas chromatography and atomic absorption spectrometry detection in a quartz cell furnace (HG/GC/QFAAS) device have been optimized in order to develop an efficient and sensitive method for arsenic compounds speciation. Good performances were obtained with absolute detection limits in the range of 0.1 - 0.5 ng for arsenite, arsenate, mono-methyl-arsonic acid (MMAA), dimethyl-arsinic acid (DMAA) and trimethyl-arsine oxide (TMAO). A pH selective reduction for inorganic arsenic speciation was successfully reported. Application to the accurate determination of arsenic compounds in different environmental samples was performed. (authors)

  7. Dosage de l'arsenic dans les charges de reformage catalytique par absorption atomique sans flamme Titration of Arsenic by Flameless Atomic Absorption in Catalytic Reforming Feedstocks

    Directory of Open Access Journals (Sweden)

    La Villa F.

    2006-11-01

    Full Text Available Nous décrivons une méthode de dosage de l'arsenic dans les charges de reformage catalytique par absorption atomique sans flamme. Après traitement de l'échantillon par une solution d'iode dans le toluène, l'arsenic est extrait par de l'acide nitrique dilué. L'addition de nitrate de magnésium a pour but de rendre l'arsenic extrait moins volatil. La méthode décrite permet d'atteindre une limite de détection de un microgramme par litre. Elle peut être appliquée à d'autres types de naphtas que les charges de reformage catalytique. This article describes a method for titrating arsenic in catalytic reforming feedstocks by flameless atomic absorption. After the sample has been treated by an iodine solution in toluene, the arsenic is extracted by diluted nitric acid. Magnesium nitrate is added sa as ta make the extracted arsenic less volatile. This method is capable of attaining a detection limit of one microgrom per liter. It con be applied to types of naphthos other than catalytic reforming feedstocks.

  8. Mercury in Environmental and Biological Samples Using Online Combustion with Sequential Atomic Absorption and Fluorescence Measurements: A Direct Comparison of Two Fundamental Techniques in Spectrometry

    Science.gov (United States)

    Cizdziel, James V.

    2011-01-01

    In this laboratory experiment, students quantitatively determine the concentration of an element (mercury) in an environmental or biological sample while comparing and contrasting the fundamental techniques of atomic absorption spectrometry (AAS) and atomic fluorescence spectrometry (AFS). A mercury analyzer based on sample combustion,…

  9. Application of methane as a gaseous modifier for the determination of silicon using electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Heinrich, Hans-Joachim, E-mail: hans-joachim.heinrich@bam.de; Kipphardt, Heinrich

    2012-04-15

    For determination of silicon in aqueous solutions by electrothermal atomic absorption spectrometry methane/argon mixtures as a gaseous modifier were applied during the pyrolysis step to improve the analytical performance. The beneficial effects observed on thermal stabilization, signal enhancement and shape of absorbance signals were attributed to the thermal decomposition products of methane, which were hydrogen and carbon black (soot). Using a 5% CH{sub 4} mixture with argon, the optimized pyrolysis and atomization temperatures were 1350 Degree-Sign C and 2450 Degree-Sign C, respectively. A flushing step following the pyrolysis was mandatory to avoid background absorption and accelerated deposition of pyrolytic graphite. Characteristic masses of 50 and 30 pg were obtained for standard transversely heated graphite atomizer (THGA) tubes and end-capped THGA tubes, respectively, which were lower than with other previously applied modifiers. A limit of detection of 0.2 {mu}g L{sup -1} (3 s, n = 10) has been obtained. In addition, this gaseous modifier did not contribute to contamination which often was significant when a liquid modifier solution was co-injected. The proposed method has been applied to the determination of silicon in ultrapure water, nitric and hydrochloric acids. - Highlights: Black-Right-Pointing-Pointer CH{sub 4}/Ar gas mixtures act as new modifier in the determination of Si using ET AAS. Black-Right-Pointing-Pointer CH{sub 4} improved thermal stabilization, atomization efficiency and signal shape of Si. Black-Right-Pointing-Pointer Optimum performance by addition of 5% CH{sub 4} during pyrolysis at 1350 Degree-Sign C. Black-Right-Pointing-Pointer Gaseous modifier does not contribute to blank values. Black-Right-Pointing-Pointer Optimized method suitable for determination of Si in ultrapure reagents.

  10. Atoms

    Institute of Scientific and Technical Information of China (English)

    刘洪毓

    2007-01-01

    Atoms(原子)are all around us.They are something like the bricks (砖块)of which everything is made. The size of an atom is very,very small.In just one grain of salt are held millions of atoms. Atoms are very important.The way one object acts depends on what

  11. Simple Atomic Absorption Spectroscopic and Spectrophotometric Methods for Determination of Pioglitazone Hydrochloride and Carvedilol in Pharmaceutical Dosage Forms

    Directory of Open Access Journals (Sweden)

    Afaf A. Abdelmonem

    2014-01-01

    Full Text Available This study represents simple atomic absorption spectroscopic and spectrophotometric methods for determination of pioglitazone hydrochloride (PGZ-HCl and carvedilol (CRV based on formation of ion-pair associates between drugs and inorganic complex, bismuth(III tetraiodide (Method A and between drugs and organic acidic dyes, fast green and orange G (Method B. Method A is based on formation of ion-pair associate between drugs and bismuth(III tetraiodide in acidic medium to form orange-red ion-pair associates, which can be quantitatively determined by two different procedures. The formed ion-pair associate is extracted by methylene chloride, dissolved in acetone, dried, and then decomposed by hydrochloric acid, and bismuth content is determined by direct atomic absorption spectrometric technique (Procedure 1 or extracted by methylene chloride, dissolved in acetone, and quantified spectrophotometrically at 490 nm (Procedure 2. Method B is based on formation of ion-pair associate between drugs and either fast green dye or orange G dye in acidic medium to form ion-pair associates. The formed ion-pair associate is extracted by methylene chloride and quantified spectrophotometrically at 630 nm (for fast green dye method or 498 nm (for orange G dye method. Optimal experimental conditions have been studied. Both methods are applied for determination of the drugs in tablets without interference.

  12. MERCURY QUANTIFICATION IN SOILS USING THERMAL DESORPTION AND ATOMIC ABSORPTION SPECTROMETRY: PROPOSAL FOR AN ALTERNATIVE METHOD OF ANALYSIS

    Directory of Open Access Journals (Sweden)

    Liliane Catone Soares

    2015-08-01

    Full Text Available Despite the considerable environmental importance of mercury (Hg, given its high toxicity and ability to contaminate large areas via atmospheric deposition, little is known about its activity in soils, especially tropical soils, in comparison with other heavy metals. This lack of information about Hg arises because analytical methods for determination of Hg are more laborious and expensive compared to methods for other heavy metals. The situation is even more precarious regarding speciation of Hg in soils since sequential extraction methods are also inefficient for this metal. The aim of this paper is to present a technique of thermal desorption associated with atomic absorption spectrometry, TDAAS, as an efficient tool for quantitative determination of Hg in soils. The method consists of the release of Hg by heating, followed by its quantification by atomic absorption spectrometry. It was developed by constructing calibration curves in different soil samples based on increasing volumes of standard Hg2+ solutions. Performance, accuracy, precision, and quantification and detection limit parameters were evaluated. No matrix interference was detected. Certified reference samples and comparison with a Direct Mercury Analyzer, DMA (another highly recognized technique, were used in validation of the method, which proved to be accurate and precise.

  13. Determination of mercury in an assortment of dietary supplements using an inexpensive combustion atomic absorption spectrometry technique.

    Science.gov (United States)

    Levine, Keith E; Levine, Michael A; Weber, Frank X; Hu, Ye; Perlmutter, Jason; Grohse, Peter M

    2005-01-01

    The concentrations of mercury in forty, commercially available dietary supplements, were determined using a new, inexpensive analysis technique. The method involves thermal decomposition, amalgamation, and detection of mercury by atomic absorption spectrometry with an analysis time of approximately six minutes per sample. The primary cost savings from this approach is that labor-intensive sample digestion is not required prior to analysis, further automating the analytical procedure. As a result, manufacturers and regulatory agencies concerned with monitoring lot-to-lot product quality may find this approach an attractive alternative to the more classical acid-decomposition, cold vapor atomic absorption methodology. Dietary supplement samples analyzed included astragalus, calcium, chromium picolinate, echinacea, ephedra, fish oil, ginger, ginkgo biloba, ginseng, goldenseal, guggul, senna, St John's wort, and yohimbe products. Quality control samples analyzed with the dietary supplements indicated a high level of method accuracy and precision. Ten replicate preparations of a standard reference material (NIST 1573a, tomato leaves) were analyzed, and the average mercury recovery was 109% (2.0% RSD). The method quantitation limit was 0.3 ng, which corresponded to 1.5 ng/g sample. The highest found mercury concentration (123 ng/g) was measured in a concentrated salmon oil sample. When taken as directed by an adult, this product would result in an approximate mercury ingestion of 7 mug per week.

  14. A preconcentration system for determination of copper and nickel in water and food samples employing flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Tuzen, Mustafa [Department of Chemistry, Gaziosmanpasa University, 60250 Tokat (Turkey); Soylak, Mustafa [Department of Chemistry, Erciyes University, 38039 Kayseri (Turkey)], E-mail: soylak@erciyes.edu.tr; Citak, Demirhan [Department of Chemistry, Gaziosmanpasa University, 60250 Tokat (Turkey); Ferreira, Hadla S.; Korn, Maria G.A. [Universidade Federal da Bahia, Instituto de Quimica, 40170-290 Salvador (Brazil); Bezerra, Marcos A. [Universidade Estadual do Sudoeste da Bahia, 45200-190 Jequie (Brazil)

    2009-03-15

    A separation/preconcentration procedure using solid phase extraction has been proposed for the flame atomic absorption spectrometric determination of copper and nickel at trace level in food samples. The solid phase is Dowex Optipore SD-2 resin contained on a minicolumn, where analyte ions are sorbed as 5-methyl-4-(2-thiazolylazo) resorcinol chelates. After elution using 1 mol L{sup -1} nitric acid solution, the analytes are determinate employing flame atomic absorption spectrometry. The optimization step was performed using a full two-level factorial design and the variables studied were: pH, reagent concentration (RC) and amount of resin on the column (AR). Under the experimental conditions established in the optimization step, the procedure allows the determination of copper and nickel with limit of detection of 1.03 and 1.90 {mu}g L{sup -1}, respectively and precision of 7 and 8%, for concentrations of copper and nickel of 200 {mu}g L{sup -1}. The effect of matrix ions was also evaluated. The accuracy was confirmed by analyzing of the followings certified reference materials: NIST SRM 1515 Apple leaves and GBW 07603 Aquatic and Terrestrial Biological Products. The developed method was successfully applied for the determination of copper and nickel in real samples including human hair, chicken meat, black tea and canned fish.

  15. [Determination of trace silver in water samples by solid phase extraction portable tungsten-coil electrothermal atomic absorption spectrometry].

    Science.gov (United States)

    Fan, Guang-yu; Jiang, Xiao-ming; Zheng, Cheng-bin; Hou, Xian-deng; Xu, Kai-lai

    2011-07-01

    A simple method has been developed for the determination of silver in environmental water samples using solid phase extraction with tungsten-coil electrothermal atomic absorption spectrometry. Silica gel was used as an adsorbent and packed into a syringe barrel for solid phase extraction of silver prior to its determination by using a portable tungsten-coil electrothermal atomic absorption spectrometer. Optimum conditions for adsorption and desorption of silver ion, as well as interferences from co-existing ions, were investigated. A sample pH value of 6.0, a sample loading flow rate of 4.0 mL x min(-1), and the mixture of 4% (m/v) thiourea and 2% (phi) nitrate acid with the eluent flow rate of 0.5 mL x min(-1) for desorption were selected for further studies. Under optimal conditions, a linear range of 0.20-4.00 ng x mL(-1), a limit of detection (3sigma) of 0.03 ng x mL(-1) and a preconcentration factor of 94 were achieved. The proposed method was validated by testing three environmental water samples with satisfactory results.

  16. Colorimetric and atomic absorption spectrometric determination of mucolytic drug ambroxol through ion-pair formation with iron and thiocyanate.

    Science.gov (United States)

    Levent, Abdulkadir; Sentürk, Zühre

    2010-09-01

    Colorimetric and atomic absorption spectrometric methods have been developed for the determination of mucolytic drug Ambroxol. These procedures depend upon the reaction of iron(III) metal ion with the drug in the presence of thiocyanate ion to form stable ion-pair complex which extractable chloroform. The red-coloured complex was determined either colorimetrically at 510 nm or by indirect atomic absorption spectrometry (AAS) via the determination of the iron content in the formed complex. The optimum experimental conditions for pH, concentrations of Fe(3+) and SCN(-), shaking time, phase ratio, and the number of extractions were determined. Under the proposed conditions, linearity was obeyed in the concentration ranges 4.1x10(-6) - 5.7x10(-5) M (1.7-23.6 µg mL(-1)) using both methods, with detection limits of 4.6x10(-7) M (0.19 µg mL(-1)) for colorimetry and 1.1x10(-6) M (0.46 µg mL(-1)) for AAS. The proposed methods were applied for the determination of Ambroxol in tablet dosage forms. The results obtained were statistically analyzed and compared with those obtained by applying the high-performance liquid chromatographic method with diode-array detection.

  17. Chromium speciation by solid phase extraction on Dowex M 4195 chelating resin and determination by atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Saygi, Kadriye Ozlem; Tuzen, Mustafa [Gaziosmanpasa University, Faculty of Science and Arts, Chemistry Department, 60250 Tokat (Turkey); Soylak, Mustafa [Erciyes University, Faculty of Science and Arts, Chemistry Department, 38039 Kayseri (Turkey)], E-mail: msoylak@gmail.com; Elci, Latif [Pamukkale University, Faculty of Science and Arts, Chemistry Department, 20020 Denizli (Turkey)

    2008-05-30

    A solid phase extraction procedure has been established for chromium speciation in natural water samples prior to determination by atomic absorption spectrometry. The procedure is based on the solid phase extraction of the Cr(VI)- Dowex M 4195 chelating resin. After oxidation of Cr(III) to Cr(VI) by using H{sub 2}O{sub 2}, the presented method was applied to the determination of the total chromium. The level of Cr(III) is calculated by difference of total chromium and Cr(VI) levels. The procedure was optimized for some analytical parameters including pH, eluent type, flow rates of sample and eluent, matrix effects, etc. The presented method was applied for the speciation of chromium in natural water samples with satisfactory results (recoveries >95%, RSDs <10%). In the determinations of chromium species, flame atomic absorption spectrometer was used. The results were checked by using NIST SRM 2711 Montana soil and GBW 07603 Bush branched and leaves.

  18. Contents of cadmium, mercury and lead in fish from the Atlantic sea (Morocco) determined by atomic absorption spectrometry.

    Science.gov (United States)

    Chahid, Adil; Hilali, Mustapha; Benlhachimi, Abdeljalil; Bouzid, Taoufiq

    2014-03-15

    As a part of a specific monitoring program, lead (Pb) cadmium (Cd) and mercury (Hg) concentrations in important species of fish from various fishing ports of the southern Kingdom of Morocco (Sardina pilchardus, Scomber scombrus, Plectorhinchus mediterraneus, Trachurus trachurus, Octopus vulgaris, Boops boops, Sarda sarda, Trisopterus capelanus, and Conger conger) were investigated by the Moroccan Reference Laboratory (NRL) for trace elements in foodstuffs of animal origin. The samples were analysed for lead and cadmium by a graphite furnace atomic absorption spectrometry (GFAAS); and for mercury by cold vapour atomic absorption spectrometry (CVAAS). The results were expressed as μg/g of wet weight (w/w). The levels of Cd, Pb and Hg in muscles of fish were 0.009-0.036, 0.013-0.114 and 0.049-0.194 μg/g, respectively. The present study showed that different metals were present in the sample at different levels but within the maximum residual levels prescribed by the EU for the fish and shellfish from these areas, in general, should cause no health problems for consumers.

  19. Extended x-ray absorption fine structure studies of the atomic structure of nanoparticles in different metallic matrices.

    Science.gov (United States)

    Baker, S H; Roy, M; Gurman, S J; Binns, C

    2009-05-06

    It has been appreciated for some time that the novel properties of particles in the size range 1-10 nm are potentially exploitable in a range of applications. In order to ultimately produce commercial devices containing nanosized particles, it is necessary to develop controllable means of incorporating them into macroscopic samples. One way of doing this is to embed the nanoparticles in a matrix of a different material, by co-deposition for example, to form a nanocomposite film. The atomic structure of the embedded particles can be strongly influenced by the matrix. Since some of the key properties of materials, including magnetism, strongly depend on atomic structure, the ability to determine atomic structure in embedded nanoparticles is very important. This review focuses on nanoparticles, in particular magnetic nanoparticles, embedded in different metal matrices. Extended x-ray absorption fine structure (EXAFS) provides an excellent means of probing atomic structure in nanocomposite materials, and an overview of this technique is given. Its application in probing catalytic metal clusters is described briefly, before giving an account of the use of EXAFS in determining atomic structure in magnetic nanocomposite films. In particular, we focus on cluster-assembled films comprised of Fe and Co nanosized particles embedded in various metal matrices, and show how the crystal structure of the particles can be changed by appropriate choice of the matrix material. The work discussed here demonstrates that combining the results of structural and magnetic measurements, as well as theoretical calculations, can play a significant part in tailoring the properties of new magnetic cluster-assembled materials.

  20. DETERMINATION OF COPPER AND ZINC IN MINERAL WATERS BY ATOMIC ABSORPTION SPECTROPHOTOMETRY

    Directory of Open Access Journals (Sweden)

    Tatiana Mitina

    2011-12-01

    Full Text Available The content of copper and zinc in mineral waters were determined by atomic spectroscopy with preliminary extraction of metals. Validation of the technique was carried out by the method of standard additions and proved the reliability of analytical data.

  1. Application of microemulsions in determination of chromium naphthenate in gasoline by flame atomic absorption spectroscopy.

    Science.gov (United States)

    Du, B; Wei, Q; Wang, S; Yu, W

    1997-10-01

    A new method using microemulsified samples is presented. It is for the determination of chromium naphthenate in gasoline by flame absorption spectroscopy. The method has the advantage of simplicity, speed and the use of aqueous standards for calibration instead of organic standards. Coexistent elements do not disturb the determination. Results obtained by this method were better than those obtained by other methods for the same samples.

  2. Determination of cadmium in rice and water by tungsten coil electrothermal vaporization-atomic fluorescence spectrometry and tungsten coil electrothermal atomic absorption spectrometry after cloud point extraction

    Energy Technology Data Exchange (ETDEWEB)

    Wen Xiaodong [College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu, Sichuan 610064 (China); Wu Peng [Analytical and Testing Center, Sichuan University, 29 Wangjiang Road, Chengdu, Sichuan 610064 (China); Chen Li [College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu, Sichuan 610064 (China); Hou Xiandeng, E-mail: houxd@scu.edu.cn [College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu, Sichuan 610064 (China); Analytical and Testing Center, Sichuan University, 29 Wangjiang Road, Chengdu, Sichuan 610064 (China)

    2009-09-14

    In this work, the microsampling nature of tungsten coil electrothermal vaporization Ar/H{sub 2} flame atomic fluorescence spectrometry (W-coil ETV-AFS) as well as tungsten coil electrothermal atomic absorption spectrometry (W-coil ET-AAS) was used with cloud point extraction (CPE) for the ultrasensitive determination of cadmium in rice and water samples. When the temperature of the extraction system is higher than the cloud point temperature of the selected surfactant Triton X-114, the complex of cadmium with dithizone can be quantitatively extracted into the surfactant-rich phase and subsequently separated from the bulk aqueous phase by centrifugation. The main factors affecting the CPE, such as concentration of Triton X-114 and dithizone, pH, equilibration temperature and incubation time, were optimized for the best extract efficiency. Under the optimal conditions, the limits of detection for cadmium by W-coil ETV-AFS and W-coil ET-AAS were 0.01 and 0.03 {mu}g L{sup -1}, with sensitivity enhancement factors of 152 and 93, respectively. The proposed methods were applied to the determination of cadmium in certified reference rice and water samples with analytical results in good agreement with certified values.

  3. Direct determination of cadmium in Orujo spirit samples by electrothermal atomic absorption spectrometry: Comparative study of different chemical modifiers

    Energy Technology Data Exchange (ETDEWEB)

    Vilar Farinas, M. [Departamento de Quimica Analitica, Nutricion y Bromatologia, Facultad de Ciencias, Universidad de Santiago de Compostela, Campus de Lugo, 27002 Lugo (Spain); Barciela Garcia, J. [Departamento de Quimica Analitica, Nutricion y Bromatologia, Facultad de Ciencias, Universidad de Santiago de Compostela, Campus de Lugo, 27002 Lugo (Spain); Garcia Martin, S. [Departamento de Quimica Analitica, Nutricion y Bromatologia, Facultad de Ciencias, Universidad de Santiago de Compostela, Campus de Lugo, 27002 Lugo (Spain); Pena Crecente, R. [Departamento de Quimica Analitica, Nutricion y Bromatologia, Facultad de Ciencias, Universidad de Santiago de Compostela, Campus de Lugo, 27002 Lugo (Spain); Herrero Latorre, C. [Departamento de Quimica Analitica, Nutricion y Bromatologia, Facultad de Ciencias, Universidad de Santiago de Compostela, Campus de Lugo, 27002 Lugo (Spain)]. E-mail: cherrero@lugo.usc.es

    2007-05-22

    In this work, several analytical methods are proposed for cadmium determination in Orujo spirit samples using electrothermal atomic absorption spectrometry (ETAAS). Permanent chemical modifiers thermally coated on the platforms inserted in pyrolytic graphite tubes (such as W, Ir, Ru, W-Ir and W-Ru) were comparatively studied in relation to common chemical modifier mixtures [Pd-Mg(NO{sub 3}){sub 2} and (NH{sub 4})H{sub 2}PO{sub 4}-Mg(NO{sub 3}){sub 2}] for cadmium stabilization. Different ETAAS Cd determination methods based on the indicated modifiers have been developed. In each case, pyrolysis and atomization temperatures, atomization shapes, characteristic masses and detection limits as well as other analytical characteristics have been determined. All the assayed modifiers (permanent and conventional) were capable of achieving the appropriate stabilization of the analyte, with the exception of Ru and W-Ru. Moreover, for all developed methods, recoveries (99-102%) and precision (R.S.D. lower than 10%) were acceptable. Taking into account the analytical performance (best detection limit LOD = 0.01 {mu}g L{sup -1}), the ETAAS method based on the use of W as a permanent modifier was selected for further direct Cd determinations in Orujo samples from Galicia (NW Spain). The chosen method was applied in the determination of the Cd content in 38 representative Galician samples. The cadmium concentrations ranged

  4. Determination of Ultratrace Amounts of Copper(Ⅱ) in Water Samples by Electrothermal Atomic Absorption Spectrometry After Cloud Point Extraction

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A novel approach was developed for the determination of ultratrace amounts of copper in water samples by using electrothermal atomic absorption spectrometry (ETAAS) after cloud point extraction (CPE). 1-( 2-Pyridylazo)-2-naphthol was used as the chelating reagent and Triton X-114 as the micellar-forming surfactant. CPE was conducted in a pH 8.0 medium at 40 ℃ for 10 min. After the separation of the phases by centrifugation, the surfactant-rich phase was diluted with 1 mL of a methanol solution of 0. 1 mol/L HNO3. Then 20 μL of the diluted surfactant-rich phase was injected into the graphite furnace for atomization in the absence of any matrix modifier. Various experimental conditions that affect the extraction and atomization processes were optimized. A detection limit of 5 ng/L was obtained after preconcentration. The linear dynamic range of the copper mass concentration was found to be 0-2.0ng/mL, and the relative standard deviation was found to be less than 3.1% for a sample containing 1.0 ng/mL Cu(Ⅱ). This developed method was successfully applied to the determination of ultratrace amounts of Cu in drinking water, tap water, and seawater samples.

  5. Nickel and strontium nitrates as modifiers for the determination of selenium in wine by Zeeman electrothermal atomic absorption spectrometry.

    Science.gov (United States)

    Cvetković, J; Stafilov, T; Mihajlović, D

    2001-08-01

    A mixed matrix modifier of nickel and strontium nitrates was used as a chemical modifier for the determination of selenium in wines by Zeeman electrothermal atomic absorption spectrometry. Wine samples were heated on a boiling water bath with small amounts of nitric acid and hydrogen peroxide. For complete elimination of interference, especially from sulfates and phosphates, selenium is complexed with ammonium pyrolidinedithiocarbamate (APDTC), extracted into methyl isobutyl ketone (MIBK), and measured by ETAAS. The graphite furnace temperature program was optimized for both aqueous and organic solutions. Pyrolysis temperatures of 1300 degrees C and 800 degrees C were chosen for aqueous and organic solutions, respectively; 2700 degrees C and 2100 degrees C were used as optimum atomization temperatures for aqueous and organic solutions, respectively. The optimum modifier mass established is markedly lower than those presented in the literature. The platform atomization ensures pretreatment stabilization up to 1100 degrees C and 1600 degrees C, respectively, for organic and aqueous selenium solutions. The procedure was verified by the method of standard addition. The investigated wine samples originated from the different regions of the Republic of Macedonia. The selenium concentration varied from not detectable to 0.93 microg L(-1).

  6. Graphite furnace atomic absorption spectrometry as a routine method for the quantification of beryllium in blood and serum

    Directory of Open Access Journals (Sweden)

    Brousseau Pauline

    2008-07-01

    Full Text Available Abstract Background A routine method for the quantification of beryllium in biological fluids is essential for the development of a chelation therapy for Chronic Beryllium Disease (CBD. We describe a procedure for the direct determination of beryllium in undigested micro quantities of human blood and serum using graphite furnace atomic absorption spectrometry. Blood and serum samples are prepared respectively by a simple 8-fold and 5-fold dilution with a Nash Reagent. Three experimental setups are compared: using no modifier, using magnesium nitrate and using palladium/citric acid as chemical modifiers. Results In serum, both modifiers did not improve the method sensitivity, the optimal pyrolysis and atomization temperatures are 1000°C and 2900°C, respectively. In blood, 6 μg of magnesium nitrate was found to improve the method sensitivity. The optimal pyrolysis and atomization temperatures were 800°C and 2800°C respectively. Conclusion In serum, the method detection limit was 2 ng l-1, the characteristic mass was 0.22 (± 0.07 pg and the accuracy ranged from 95 to 100%. In blood, the detection limit was 7 ng l-1, the characteristic mass was 0.20 (± 0.02 pg and the accuracy ranged from 99 to 101%.

  7. Simultaneous preconcentration of Co(II), Ni(II), Cu(II), and Cd(II) from environmental samples on Amberlite XAD-2000 column and determination by FAAS

    Energy Technology Data Exchange (ETDEWEB)

    Duran, Celal [Department of Chemistry, Faculty of Arts and Sciences, Karadeniz Technical University, 61080 Trabzon (Turkey)], E-mail: cduran@ktu.edu.tr; Senturk, Hasan Basri [Department of Chemistry, Faculty of Arts and Sciences, Karadeniz Technical University, 61080 Trabzon (Turkey); Elci, Latif [Department of Chemistry, Faculty of Arts and Sciences, Pamukkale University, 20020 Denizli (Turkey); Soylak, Mustafa [Department of Chemistry, Faculty of Arts and Sciences, Erciyes University, 38039 Kayseri (Turkey); Tufekci, Mehmet [Department of Chemistry, Faculty of Arts and Sciences, Karadeniz Technical University, 61080 Trabzon (Turkey)

    2009-02-15

    A new method for the preconcentration of some trace metals (Co, Ni, Cu, and Cd) as complexed with ammonium pyrrolidynedithiocarbamate (APDC) was developed using a mini-column filled with Amberlite XAD-2000 resin. Metal contents were determined by flame atomic absorption spectrometry (FAAS) after the metal complexes accumulated on the resin were eluted with 1 M HNO{sub 3} in acetone. The effects of the analytical parameters such as sample pH, quantity of complexing agent, eluent type, resin quantity, sample volume, sample flow rate, and matrix ions were investigated on the recovery of the metals from aqueous solutions. The relative standard deviation (R.S.D.) of the method was <6%. The validation of the method was confirmed using two certified reference materials (CRM TMDW-500 Drinking Water and CRM SA-C Sandy Soil C). The method was successfully applied to some stream waters and mushroom samples from Eastern Black Sea Region (Trabzon city) of Turkey.

  8. Determination of cadmium in alcohol fuel using Moringa oleifera seeds as a biosorbent in an on-line system coupled to FAAS.

    Science.gov (United States)

    Alves, Vanessa Nunes; Mosquetta, Rafael; Coelho, Nívia Maria Melo; Bianchin, Joyce Nunes; Di Pietro Roux, Kalya Cravo; Martendal, Edmar; Carasek, Eduardo

    2010-01-15

    In this study a new method for determination of cadmium in alcohol fuel using Moringa oleifera seeds as a biosorbent in an on-line preconcentration system coupled to flame atomic absorption spectrometry (FAAS) was developed. Flow and chemical variables of the proposed system were optimized through multivariate designs. The limit of detection for cadmium was 5.50microg L(-1) and the precision was below 2.3% (35.0microg L(-1), n=9). The analytical curve was linear from 5 to 150microg L(-1), with a correlation coefficient of 0.9993. The developed method was successfully applied to spiked alcohol fuel, and accuracy was assessed through recovery tests, with recovery ranging from 97.50 to 100%.

  9. Simultaneous preconcentration of Co(II), Ni(II), Cu(II), and Cd(II) from environmental samples on Amberlite XAD-2000 column and determination by FAAS.

    Science.gov (United States)

    Duran, Celal; Senturk, Hasan Basri; Elci, Latif; Soylak, Mustafa; Tufekci, Mehmet

    2009-02-15

    A new method for the preconcentration of some trace metals (Co, Ni, Cu, and Cd) as complexed with ammonium pyrrolidynedithiocarbamate (APDC) was developed using a mini-column filled with Amberlite XAD-2000 resin. Metal contents were determined by flame atomic absorption spectrometry (FAAS) after the metal complexes accumulated on the resin were eluted with 1M HNO(3) in acetone. The effects of the analytical parameters such as sample pH, quantity of complexing agent, eluent type, resin quantity, sample volume, sample flow rate, and matrix ions were investigated on the recovery of the metals from aqueous solutions. The relative standard deviation (R.S.D.) of the method was <6%. The validation of the method was confirmed using two certified reference materials (CRM TMDW-500 Drinking Water and CRM SA-C Sandy Soil C). The method was successfully applied to some stream waters and mushroom samples from Eastern Black Sea Region (Trabzon city) of Turkey.

  10. Investigation of an alternating current plasma as an element selective atomic emission detector for high-resolution capillary gas chromatography and as a source for atomic absorption and atomic emission spectrometry

    Science.gov (United States)

    Ombaba, Jackson M.

    This thesis deals with the construction and evaluation of an alternating current plasma (ACP) as an element-selective detector for high resolution capillary gas chromatography (GC) and as an excitation source for atomic absorption spectrometry (AAS) and atomic emission spectrometry (AES). The plasma, constrained in a quartz discharge tube at atmospheric pressure, is generated between two copper electrodes and utilizes helium as the plasma supporting gas. The alternating current plasma power source consists of a step-up transformer with a secondary output voltage of 14,000 V at a current of 23 mA. The device exhibits a stable signal because the plasma is self-seeding and reignites itself every half cycle. A tesla coil is not required to commence generation of the plasma if the ac voltage applied is greater than the breakdown voltage of the plasma-supporting gas. The chromatographic applications studied included the following: (1) the separation and selective detection of the organotin species, tributyltin chloride (TBT) and tetrabutyltin (TEBT), in environmental matrices including mussels (Mvutilus edullus) and sediment from Boston Harbor, industrial waste water and industrial sludge, and (2) the detection of methylcyclopentadienyl manganesetricarbonyl (MMT) and similar compounds used as gasoline additives. An ultrasonic nebulizer (common room humidifier) was utilized as a sample introduction device for aqueous solutions when the ACP was employed as an atomization source for atomic absorption spectrometry and as an excitation source for atomic emission spectrometry. Plasma diagnostic parameters studied include spatial electron number density across the discharge tube, electronic, excitation and ionization temperatures. Interference studies both in absorption and emission modes were also considered. Figures of merits of selected elements both in absorption and emission modes are reported. The evaluation of a computer-aided optimization program, Drylab GC, using

  11. Theory of x-ray absorption by laser-dressed atoms

    CERN Document Server

    Buth, C; Buth, Christian; Santra, Robin

    2006-01-01

    An ab initio theory is devised for the x-ray photoabsorption cross section of atoms in the field of a moderately intense optical laser (10^13 W/cm^2). The laser dresses the core-excited atomic states, which introduces a dependence of the cross section on the angle between the polarization vectors of the two linearly polarized radiation sources. We use the Hartree-Fock-Slater approximation to describe the atomic many-body problem in conjunction with a non-relativistic quantum-electrodynamic approach to treat the photon-electron interaction. The continuum wave functions of ejected electrons are treated with a complex absorbing potential that is derived from smooth exterior complex scaling. The solution to the two-color (x-ray plus laser) problem is discussed in terms of a direct diagonalization of the complex symmetric matrix representation of the Hamiltonian. Alternative treatments with time-independent and time-dependent non-Hermitian perturbation theories are presented that exploit the weak interaction stren...

  12. Tunable electronic and magnetic properties in stanene by 3d transition metal atoms absorption

    Science.gov (United States)

    Xing, Dan-Xu; Ren, Ceng-Ceng; Zhang, Shu-Feng; Feng, Yong; Chen, Xin-Lian; Zhang, Chang-Wen; Wang, Pei-Ji

    2017-03-01

    The electronic and magnetic properties of transition metal (TM) atoms (V, Cr, Mn, Fe, Co, Ni) adsorption on stanene are investigated by first-principles calculations. The results indicate that the TM atoms prefer to be relaxed on a H site on stanene except V atom which lies on the valley site. Fe-absorbed stanene is a spin gapless semiconductor with up-spin electron and down-spin hole carriers allowing the coexistence of charge current and the pure spin current. Co-absorbed stanene lies in the half metal phase. The V-, Cr-, Mn-, and Cu-absorbed stanene turn the stanene into metal, while Ni- and Zn-absorbed stanene open a narrow band gap. For V-, Cr-, Mn-, Fe-, and Co-absorbed stanene, the magnetic moment of the TM will survive while the Ni-, Cu-, and Zn-absorbed stanene will be non-magnetic material. These findings may have great potential in the design of new electrically controllable spintronic devices.

  13. Optimization of a cloud point extraction procedure with response surface methodology for the quantification of dissolved iron in produced water from the petroleum industry using FAAS.

    Science.gov (United States)

    Gondim, Tamyris A; Guedes, Jhonyson A C; Ribeiro, Livia P D; Lopes, Gisele S; Matos, Wladiana O

    2017-01-30

    The characterization of inorganic elements in the produced water (PW) samples is a difficult task because of the complexity of the matrix. This work deals with a study of a methodology for dissolved Fe quantification in PW from oil industry by flame atomic absorption spectrometry (FAAS) after cloud point extraction (CPE). The procedure is based on the CPE using PAN as complexing agent and Triton X-114 as surfactant. The best conditions for Fe extraction parameters were studied using a Box-Behnken design. The proposed method presented a LOQ of 0.010μgmL(-1) and LOD of 0.003μgmL(-1). The precision of the method was evaluated in terms of repeatability, obtaining a coefficient of variation of 2.54%. The accuracy of the method was assessed by recovery experiments of Fe spiked that presented recovery of 103.28%. The method was applied with satisfactory performance to determine Fe by FAAS in PW samples.

  14. Determination of silicon and aluminum in silicon carbide nanocrystals by high-resolution continuum source graphite furnace atomic absorption spectrometry.

    Science.gov (United States)

    Dravecz, Gabriella; Bencs, László; Beke, Dávid; Gali, Adam

    2016-01-15

    The determination of Al contaminant and the main component Si in silicon carbide (SiC) nanocrystals with the size-distribution of 1-8nm dispersed in an aqueous solution was developed using high-resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS-GFAAS). The vaporization/atomization processes were investigated in a transversally heated graphite atomizer by evaporating solution samples of Al and Si preserved in various media (HCl, HNO3). For Si, the best results were obtained by applying a mixture of 5µg Pd plus 5µg Mg, whereas for Al, 10µg Mg (each as nitrate solution) was dispensed with the samples, but the results obtained without modifier were found to be better. This way a maximum pyrolysis temperature of 1200°C for Si and 1300°C for Al could be used, and the optimum (compromise) atomization temperature was 2400°C for both analytes. The Si and Al contents of different sized SiC nanocrystals, dispersed in aqueous solutions, were determined against aqueous (external) calibration standards. The correlation coefficients (R values) of the calibrations were found to be 0.9963 for Si and 0.9991 for Al. The upper limit of the linear calibration range was 2mg/l Si and 0.25mg/l Al. The limit of detection was 3µg/l for Si and 0.5µg/l for Al. The characteristic mass (m0) was calculated to be 389pg Si and 6.4pg Al. The Si and Al content in the solution samples were found to be in the range of 1.0-1.7mg/l and 0.1-0.25mg/l, respectively.

  15. Microwave Digestion of Hair Samples in Closed Vessels for the Determinations of Copper and Iron by Derivative Flame Atomic Absorption Spectrometry using Flow-injection Technique%微波溶样-流动注射-导数火焰原子吸收光谱测定人发中的铜和铁

    Institute of Scientific and Technical Information of China (English)

    陈兰菊; 郑连义; 孙汉文

    2002-01-01

      本文以微波消解人发样,利用流动注射-导数火焰原子吸收法测定其中微量铜、铁的含量。微波溶样技术具有快捷、污染小、损失少、消化完全等优点;流动注射进样技术可以克服常规火焰原子吸收法耗样量大和基体干扰严重的缺点;导数技术应用于火焰原子吸收可提高方法的灵敏度和信号的选择性。微波溶样、流动注射与导数技术相结合应用于火焰原子吸收成功地测定了人发中的微量铜和铁。%  A new method was presented for the determinations of copper and iron in hair samples,which was based on the technique of microwave digestion in closed vessels,flow-injection and derivative flame atomic absorption spectrometry. The technique of microwave digestion is convenient, little of pollution, less in loss, and complete digestion. The flaws that sampling is large and matrix interference is serious in conventional flame atomic absorption spectrometry(FAAS) were overcome by flow-injection sampling technique. The sensitivity and signal selectivity were enhanced when derivative technique was used. This new method that derivative flame atomic absorption spectrometry combined with microwave digestion and flow-injection technique is simple and rapid with satisfactory results for determination of copper and iron in hair.

  16. Optical detection of potassium chloride vapor using collinear photofragmentation and atomic absorption spectroscopy.

    Science.gov (United States)

    Sorvajärvi, Tapio; Saarela, Jaakko; Toivonen, Juha

    2012-10-01

    A sensitive and selective optical technique to detect potassium chloride (KCl) vapor is introduced. The technique is based on the photofragmentation of KCl molecules, using a pulsed UV laser, and optical probing of the temporarily increased amount of potassium atoms with a near-infrared laser. The two laser beams are aligned to go through the sample volume along the same optical path. The performance of the technique is demonstrated by detecting KCl concentrations from 25 ppb to 30 ppm in a temperature-controlled cell.

  17. Determination of Metal Elements in Different Parts of Papaya by Flame Atomic Absorption Spectrometry with Microwave Digestion%微波消解-FAAS测定番木瓜不同部位的金属元素含量

    Institute of Scientific and Technical Information of China (English)

    袁竹连

    2013-01-01

    In order to explore the contents of metal elements in the papaya pulp,peel and seed, flame atomic absorption spectrometry (FAAS) method was used for determination of K,Na,Ca, Mg,Cu,Fe and Zn in the three parts of papaya. In addition, the digesting conditions were optimized. The results showed that under the optimized microwave digestion conditions and FAAS method, the samples were digested quickly and completely, there was a good linear relation between the concentration of the metal element standards and the absorbance value,the correlation coefficient was 0. 995 7 — 0. 999 9, the detection limit was 0. 002 — 0. 131, the recovery rate was 98. 30% —101. 67% and RSD was 0. 20%-4. 12%(n = 6). So microwave digestion-FAAS was a fast good detection method with complete digestion,less interference and stable measurement results. There were more K,Ca,Mg and less Cu,Fe,Zn in the three parts of papaya; there were more K,Mg,Cu,Zn,Fe in papaya peel and seed than in pulp,so papaya peel and seed had more advantage of development in food and medicine.%为探讨番木瓜果肉、果皮、瓜籽中金属元素的含量,采用微波消解-FAAS法测定了番木瓜3个部位的K、Na、Ca、Mg、Cu、Fe、Zn共7种金属元素的含量,并对微波消解条件进行了优化.结果显示,在优化的微波消解条件下,样品消解完全、速度快、效果好,FAAS测定的各金属元素质量浓度与吸光度均呈良好的线性关系,相关系数r为0.995 7~0.999 9,检出限为0.002~0.131,回收率为98.30%~101.67%,RSD为0.20%~4.12%(n=6),说明测定方法可靠,结果稳定;番木瓜3个部位均含有较高的K、Ca、Mg,但Cu、Fe、Zn含量均较低,与番木瓜果肉相比,番木瓜果皮和瓜籽中K、Mg、Cu、Zn、Fe含量较高,食品和药品开发优势更突出.

  18. Determination of trace metallic elements in Huidouba by flame atomic absorption spectrometry%火焰原子吸收法测定灰兜巴中微量金属元素

    Institute of Scientific and Technical Information of China (English)

    杨孝容; 王延云; 向清祥; 熊俊如

    2013-01-01

    The correlation of trace metallic elements in Huidouba and cure diabetes mellitus was established according to results of determination of metal elements in Huidouba by flame atomic absorption spectrometry (FAAS).Huidouba,old tea and dirt of con-necting Huidouba were collected as samples .The samples were extracted with water through boiling and was filtered with gauze ,then the supernatant liquid was digested by nitric acid and perchloric acid and was dissolved in dilute nitric acid and was centrifugated , the centrifugate was used as analytical solution for FAAS .Zinc(Zn),chromium(Cr),selenium(Se),magnesium(Mg),manganese (Mn),cobalt(Co),copper(Cu),nickel(Ni),cadmium(Cd)were determined by FAAS.The results showed that the contents of Cu,Ni,Cd were low in the Huidouba ,however,their values in blood and hair of diabetic patients were higher as compared to nondia -betic patients.In contrast,Zn,Cr,Se,Mg,Mn,Co were high in Huidouba ,their contents in blood and hair of diabetic patients were lower than nondiabetic patients ’s.The levels of essential trace metallic elements ,Zn,Cr,Se,Mg,Mn,Co,Cu,Ni,Cd in Huidouba samples are very beneficial to diabetes mellitus .Huidouba may play a major role in allaying or curing diabetes mellitus .%用火焰原子吸收法测定灰兜巴中微量金属元素的含量,探讨灰兜巴中微量金属元素与治疗糖尿病的相关性。采集灰兜巴以及灰兜巴连接的老茶叶和土壤试样,水煮提取、纱布过滤、静止后取其上层液,用HNO3-HClO4消解,再用稀HNO3溶解,定容,离心,取其上清液,用火焰原子吸收光谱法测定Zn、Cr、Se、Mg、Mn、Co、Cu、Ni和Cd 9种元素的含量。结果表明糖尿病人常偏高的Cu、Ni和Cd元素在灰兜巴中含量相对较低,而糖尿病人常偏低的Zn、Cr、Se、Mg、Mn和Co元素在灰兜巴中的含量相对较高。灰兜巴中Zn、Cr、Se、Mg、Mn、Co、Cu、Ni和Cd等重要微量金属元素的含量很适合糖尿病人,

  19. Effect of Atomic Absorption Spectrometry in Measuring the Contents of Lead, Cadmium and Copper in Honeysuckle%原子吸收光谱法测定金银花中铅、镉、铜的含量

    Institute of Scientific and Technical Information of China (English)

    邢凤晶; 郭琳; 常乐; 刘影

    2016-01-01

    Objective To adopt the atomic absorption spectrometry to measure the contents of lead, cadmium and copper in honeysuckle and provide data support for the objective evaluation of retail medicinal material quality in the present market. Methods After the microwave resolution of samples with concentrated nitric acid, the lead and cadmium were measured by the graphite stove method (GF-AAS), and the copper was measured by the flame method (F-AAS). Results The recovery rates of methods were respectively 104.2%, 105.4% and 114.5% and RSD were respectively 1.8%, 1.6% and 1.8%(n=6). Conclusion The measurement shows that the contents of lead, cadmium and copper in samples are lower than the limits in the current Chinese pharmacopoeia, and the method is simple and accurate with strong practicability, which can be used for the evaluation examination of medicinal materials and cut crude drugs.%目的:采用原子吸收光谱法((Atomic Absorption Spectroscopy)测定市售金银花饮片中铅、镉、铜的含量,为客观评价当前市面上零售的药材质量提供数据支持。方法样品加浓硝酸经微波消解后,用石墨炉法( GF-AAS)测定铅和镉,用火焰法( F-AAS)测定铜。结果方法的回收率分别为104.2%、105.4%、114.5%,RSD分别为1.8%、1.6%、1.8%(n=6)。结论测定样品中铅、镉、铜含量低于现行《中国药典》中的限度;该文方法简便、准确、实用性强,可用于该药材及饮片的评价性检查。

  20. Cloud point extraction thermospray flame quartz furnace atomic absorption spectrometry for determination of ultratrace cadmium in water and urine

    Science.gov (United States)

    Wu, Peng; Zhang, Yunchang; Lv, Yi; Hou, Xiandeng

    2006-12-01

    A simple, low cost and highly sensitive method based on cloud point extraction (CPE) for separation/preconcentration and thermospray flame quartz furnace atomic absorption spectrometry was proposed for the determination of ultratrace cadmium in water and urine samples. The analytical procedure involved the formation of analyte-entrapped surfactant micelles by mixing the analyte solution with an ammonium pyrrolidinedithiocarbamate (APDC) solution and a Triton X-114 solution. When the temperature of the system was higher than the cloud point of Triton X-114, the complex of cadmium-PDC entered the surfactant-rich phase and thus separation of the analyte from the matrix was achieved. Under optimal chemical and instrumental conditions, the limit of detection was 0.04 μg/L for cadmium with a sample volume of 10 mL. The analytical results of cadmium in water and urine samples agreed well with those by ICP-MS.

  1. Cloud point extraction-thermospray flame quartz furnace atomic absorption spectrometry for determination of ultratrace cadmium in water and urine

    Energy Technology Data Exchange (ETDEWEB)

    Wu Peng [Analytical and Testing Center, Sichuan University, Chengdu, Sichuan 610064 (China); Zhang Yunchang [College of Chemistry, Sichuan University, Chengdu, Sichuan 610064 (China); Lv Yi [College of Chemistry, Sichuan University, Chengdu, Sichuan 610064 (China); Hou Xiandeng [Analytical and Testing Center, Sichuan University, Chengdu, Sichuan 610064 (China) and College of Chemistry, Sichuan University, Chengdu, Sichuan 610064 (China)]. E-mail: houxd@scu.edu.cn

    2006-12-15

    A simple, low cost and highly sensitive method based on cloud point extraction (CPE) for separation/preconcentration and thermospray flame quartz furnace atomic absorption spectrometry was proposed for the determination of ultratrace cadmium in water and urine samples. The analytical procedure involved the formation of analyte-entrapped surfactant micelles by mixing the analyte solution with an ammonium pyrrolidinedithiocarbamate (APDC) solution and a Triton X-114 solution. When the temperature of the system was higher than the cloud point of Triton X-114, the complex of cadmium-PDC entered the surfactant-rich phase and thus separation of the analyte from the matrix was achieved. Under optimal chemical and instrumental conditions, the limit of detection was 0.04 {mu}g/L for cadmium with a sample volume of 10 mL. The analytical results of cadmium in water and urine samples agreed well with those by ICP-MS.

  2. Cloud point extraction and flame atomic absorption spectrometric determination of cadmium and nickel in drinking and wastewater samples.

    Science.gov (United States)

    Naeemullah; Kazi, Tasneem G; Shah, Faheem; Afridi, Hassan I; Baig, Jameel Ahmed; Soomro, Abdul Sattar

    2013-01-01

    A simple method for the preconcentration of cadmium (Cd) and nickel (Ni) in drinking and wastewater samples was developed. Cloud point extraction has been used for the preconcentration of both metals, after formation of complexes with 8-hydroxyquinoline (8-HQ) and extraction with the surfactant octylphenoxypolyethoxyethanol (Triton X-114). Dilution of the surfactant-rich phase with acidified ethanol was performed after phase separation, and the Cd and Ni contents were measured by flame atomic absorption spectrometry. The experimental variables, such as pH, amounts of reagents (8-HQ and Triton X-114), temperature, incubation time, and sample volume, were optimized. After optimization of the complexation and extraction conditions, enhancement factors of 80 and 61, with LOD values of 0.22 and 0.52 microg/L, were obtained for Cd and Ni, respectively. The proposed method was applied satisfactorily for the determination of both elements in drinking and wastewater samples.

  3. Development of a cloud point extraction and preconcentration method for Cd and Ni prior to flame atomic absorption spectrometric determination

    Energy Technology Data Exchange (ETDEWEB)

    Manzoori, Jamshid L. [Department of Analytical Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of)]. E-mail: manzoori@tabrizu.ac.ir; Karim-Nezhad, Ghasem [Department of Analytical Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of)

    2004-09-13

    In this work a new cloud point extraction (CPE) methodology was developed for the separation and preconcentration of cadmium and nickel. The analyte in the initial aqueous solution was complexed with dithizone and Triton X-114 was added as surfactant. After phase separation, based on the cloud point of the mixture, and dilution of the surfactant-rich phase with tetrahydrofuran (THF), the enriched analytes were determined by flame atomic absorption spectrometry. After optimization of the complexation and extraction conditions and preconcentration of only 10 ml of sample in the presence of 0.05% Triton X-114, the enhancement factors of 52 and 39 and the detection limits of 0.31 {mu}g l{sup -1} and 1.2 {mu}g l{sup -1} were obtained for cadmium and nickel respectively. The proposed method was applied satisfactorily to the determination of cadmium and nickel in water samples.

  4. Determination of mercury in estuarine sediments by flow injection-cold vapour atomic absorption spectrometry after microwave extraction

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Garcia, M.L.; Carlosena, A.; Lopez-Mahia, P.; Muniategui, S.; Prada, D. [University of La Coruna (Spain). Dept. Analytical Chemistry

    1999-01-01

    A flow injection-cold vapour atomic absorption spectrometric (CVAAS) method was developed for the determination of mercury at trace level in estuarine sediments using sodium tetra-hydro-borate (III) as reductant. The mercury was solubilized with nitric acid in closed vessels nd microwave oven heating. Instrumental and operational conditions (volume and concentration of reagents, reaction time, etc.) were optimized. The effect of several ions on the analytical signal was also studied; no interferences were recorded excepting for copper and nickel which caused a serious depressing effect. The detection limit obtained was 0.01 {mu}g g{sup -1}. The validation of the method was performed analyzing a certified reference sediment, BCR CRM 277 Estuarine Sediment. Good recovery (c.a. 98 %) and precision (< 3 %, RSD) were achieved. The proposed method was successfully applied to the determination of mercury in sediment samples from Ares-Betanzos Estuary (Galicia, NW Spain). (authors) 19 refs.

  5. Evaluation of trace elements in chewing tobacco and snuff using instrumental neutron activation analysis (INAA) and atomic absorption spectroscopy (AAS)

    Energy Technology Data Exchange (ETDEWEB)

    Waheed, S.; Siddique, N.; Rahman, S. [Chemistry Div., Directorate of Science, Pakistan Inst. of Nuclear Science and Tech., Islamabad (Pakistan)

    2009-07-01

    Nine samples of chewing tobacco, snuff, tobacco leaf and ash were analyzed using Instrumental Neutron Activation Analysis (INAA) and Atomic Absorption Spectroscopy (AAS). Almost all samples of chewing tobacco and snuff studied in this work contain substantial amounts of Mg, Mn, Na, K. V. Sc, Rb and Fe. Furthermore, varying amounts of Al, Ba, Ca, Ce, Co and Zn were also detected in all tobacco samples. Of the toxic elements which were determined using INAA. As, Sb and Hg were quantified in only few tobacco samples. However, other toxic elements, which were determined using AAS, such as Cu, Pb and Cd were detected in almost all samples of chewing tobacco and snuff. The concentration of majority of the detected elements is high in ash samples which imply that most elements in chewing tobacco and snuff may originate from the addition of ash. (orig.)

  6. Solid phase extraction for evaluation of occupational exposure to Pb (II) using XAD-4 sorbent prior to atomic absorption spectroscopy.

    Science.gov (United States)

    Shahtaheri, Seyed Jamaleddin; Khadem, Monireh; Golbabaei, Farideh; Rahimi-Froushan, Abbas; Ganjali, Mohammad Reza; Norouzi, Parviz

    2007-01-01

    Lead is an important constituent widely used in different industrial processes. For evaluation of workers' exposure to trace toxic metal of Pb (II), solid-phase extraction (SPE) was optimized. SPE using mini columns filled with XAD-4 resin was developed with regard to sample pH, ligand concentration, loading flow rate, elution solvent, sample volume, elution volume, the amount of resins, and sample matrix interferences. Lead ions were retained on a solid sorbent and then eluted, followed by a simple determination of analytes with flame atomic absorption spectrometery. The obtained recoveries of metal ions were greater than 92%. This method was validated with 3 different pools of spiked urine samples; it showed a good reproducibility over 6 consecutive days as well as 6 within-day experiments. This optimized method can be considered successful in simplifying sample preparation for a trace residue analysis of lead in different matrices when evaluating occupational and environmental exposures is required.

  7. Atomic absorption spectroscopy for mercury, automated by sequential injection and miniaturized in lab-on-valve system.

    Science.gov (United States)

    Erxleben, Holger; Ruzicka, Jaromir

    2005-08-15

    Sodium borohydride-based hydride generation was automated by using programmable flow within the lab-on-valve module. Mercury vapor, generated in the reaction mixture, was extracted in a gas/liquid separator. The gas-expansion separator was miniaturized and compared with the performance of a novel gas separator that exploits the combination of Venturi effect and reduced pressure. Cold vapor atomic spectroscopy was used as a model system, with detection of mercury by absorption at 254 nm and limit of detection of 9 microg of Hg/L, using 300 microL of sample and 100 microL of borohydride. This work introduces, for the first time, sequential injection technique for hydride generation, highlights advantages of using programmable flow, and outlines means for miniaturization of assays based on spectroscopy of volatile species.

  8. Design and evaluation of a continuous flow, integrated nebulizer-hydride generator for flame atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    Miguel Murillo

    2008-01-01

    Full Text Available An evaluation of the performance of a continuous flow hydride generator-nebulizer for flame atomic absorption spectrometry was carried out. Optimization of nebulizer gas flow rate, sample acid concentration, sample and tetrahydroborate uptake rates and reductant concentration, on the As and Se absorbance signals was carried out. A hydrogen-argon flame was used. An improvement of the analytical sensitivity relative to the conventional bead nebulizer used in flame AA was obtained (2 (As and 4.8 (Se µg L-1. Detection limits (3σb of 1 (As and 1.3 (Se µg L-1 were obtained. Accuracy of the method was checked by analyzing an oyster tissue reference material.

  9. Comparison of Adsorbed Mercury Screening Method With Cold-Vapor Atomic Absorption Spectrophotometry for Determination of Mercury in Soil

    Science.gov (United States)

    Easterling, Donald F.; Hovanitz, Edward S.; Street, Kenneth W.

    2000-01-01

    A field screening method for the determination of elemental mercury in environmental soil samples involves the thermal desorption of the mercury from the sample onto gold and then the thermal desorption from the gold to a gold-film mercury vapor analyzer. This field screening method contains a large number of conditions that could be optimized for the various types of soils encountered. In this study, the conditions were optimized for the determination of mercury in silty clay materials, and the results were comparable to the cold-vapor atomic absorption spectrophotometric method of determination. This paper discusses the benefits and disadvantages of employing the field screening method and provides the sequence of conditions that must be optimized to employ this method of determination on other soil types.

  10. Controlling multi-wave mixing signals via photonic band gap of electromagnetically induced absorption grating in atomic media

    CERN Document Server

    Zhang, Yiqi; Yao, Xin; Zhang, Zhaoyang; Chen, Haixia; Zhang, Huaibin; Zhang, Yanpeng

    2013-01-01

    We experimentally demonstrate dressed multi-wave mixing (MWM) and the reflection of the probe beam due to electromagnetically induced absorption (EIA) grating can coexist in a five-level atomic ensemble. The reflection is derived from the photonic band gap (PBG) of EIA grating, which is much broader than the PBG of EIT grating. Therefore, EIA-type PBG can reflect more energy from probe than EIT-type PBG does, which can effectively affect the MWM signal. The EIA-type as well as EIT-type PBG can be controlled by multiple parameters including the frequency detunings, propagation angles and powers of the involved light fields. Also, the EIA-type PBG by considering both the linear and third-order nonlinear refractive indices is also investigated. The theoretical analysis agrees well with the experimental results. This investigation has potential applications in all-optical communication and information processing.

  11. The application of solid sorbents for the purification of aluminum contaminated chemicals used as modifiers in electrothermal atomic absorption spectrometry.

    Science.gov (United States)

    Bulska, E; Pyrzyńska, K

    1996-06-01

    Various microcolumns with solid sorbents (ion exchange resins, functionalised cellulose sorbents, chelating resins) have been tested with respect to their ability for the purification of aluminum contaminated chemicals used as modifiers in electrothermal atomic absorption spectrometry. The purification of NaNO(3), Mg(NO(3))(2), K(2)SO(4) and (NH(4))(2)HPO(4) has been the most effective with an almost 100% efficiency, when Spheron-Oxine was used as chelating resin. The sorption of aluminum from KOH solution has been found to be very high (around 90%) for all investigated sorbents. However, the best results have been obtained with anion-exchange resins. It has been difficult to purify concentrated mineral acids (HCl, H(2)SO(4)). A retention of aluminum above 80% has been achieved only when Cellex P, Chelex 100 or Amberlite XAD-2 have been used.

  12. Determination of silver, bismuth, cadmium, copper, lead, and zinc in geologic materials by atomic absorption spectrometry with tricaprylylmethylammonium chloride

    Science.gov (United States)

    Viets, J.G.

    1978-01-01

    Interferences commonly encountered in the determination of silver, bismuth, cadmium, copper, lead, and zinc at crustal abundance levels are effectively eliminated using a rapid, sensitive, organic extraction technique. A potassium chlorate-hydrochloric acid digestion solubilizes the metals not tightly bound in the silicate lattice of rocks, soils, and stream sediments. The six metals are selectively extracted into a 10% Aliquat 336-MIBK organic phase in the presence of ascorbic acid and potassium iodide. Metals in the organic extract are determined by flame atomic absorption spectrometry to the 0.02-ppm level for silver, cadmium, copper, and zinc and to the 0.2-ppm level for bismuth and lead with a maximum relative standard deviation of 18.8% for known reference samples. An additional hydrofluoric acid digestion may be used to determine metals substituted in the silicate lattice.

  13. Membrane filtration of nickel(II) on cellulose acetate filters for its preconcentration, separation, and flame atomic absorption spectrometric determination

    Energy Technology Data Exchange (ETDEWEB)

    Soylak, Mustafa [Chemistry Dept., Faculty of Science Arts, University of Erciyes, Kayseri (Turkey); Unsal, Yunus Emre; Aydin, Ayse [Fen Bilimleri Enstitusu, University of Erciyes, Kayseri (Turkey); Kizil, Nebiye [Saglik Bilimleri Enstitusu, University of Erciyes, Kayseri (Turkey)

    2010-01-15

    An enrichment method for trace amounts of Ni(II), as 8-hydroxyquinoline chelates, has been established on a cellulose acetate membrane filter. Ni(II)-8-hydroxyquinoline chelates adsorbed on a membrane filter were eluted using 5 mL of 1 M HNO{sub 3}. The eluent nickel concentration was determined by a flame atomic absorption spectrometer. The influence of some analytical parameters, including pH, amount of reagent, sample volume, etc., on recovery was investigated. The interference of co-existent ions was studied. The nickel detection limit was 4.87 {mu}g/L. The method was applied to real samples for the determination of nickel(II) ions. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  14. Determination of total arsenic content in water by atomic absorption spectroscopy (AAS) using vapour generation assembly (VGA).

    Science.gov (United States)

    Behari, Jai Raj; Prakash, Rajiv

    2006-03-01

    Analysis of arsenic in water is important in view of contamination of ground water with arsenic in some parts of the world including West Bengal in India and neighboring country Bangladesh. WHO has fixed the threshold for arsenic in drinking water to 10ppb (microg/l) level, hence the methodology for determination of arsenic is required to be sensitive at ppb level. Atomic absorption spectrophotometry with vapour generation assembly (AAS-VGA) is well known technique for the trace analysis of arsenic. However, total arsenic analysis [As(III)+As(V)] is very crucial and it requires reduction of As(V) to As(III) for correct analysis. As(III) is reduced to AsH3 vapours and finally to free As atoms, which are responsible for absorption signal in AAS. To accomplish this the vapour generation assembly attached to AAS has acid channel filled with 10 M HCl and the reduction channel with sodium borohydride. Further sample can be reduced either before aspiration for analysis, using potassium iodide (KI) or the sample can be introduced in the instrument directly and KI can be added in the reduction channel along with the sodium borohydride. The present work shows that samples prepared in 3 M HCl can be reduced with KI for 30 min before introduction in the instrument. Alternatively samples can be prepared in 6 M HCl and directly aspirated in AAS using KI in VGA reduction channel. The latter methodology is more useful when the sample size is large and time cycle is difficult to maintain. It is observed that the acid concentration of the sample in both the situations plays an important role. Further reduction in acid concentration and analysis time is achieved for the arsenic analysis by using modified method. Analysis in both the methods is sensitive at ppb level.

  15. 厚朴植物叶中金属元素的含量测定%Determination of Metal Elements in the Leaves of Magnolia officinalis by Flame Atomic Absorption Spectrometry

    Institute of Scientific and Technical Information of China (English)

    李国章; 李光锋

    2011-01-01

    [Objective] To determine the content of six metal elements like Ca, Mg, Fe, Zn, Cu and Mn in M. Officinalis leaves. [Method] Digested with HNO3-HClO4 mixed acid ( 5:1 ,V/V) , the content of Ca, Mg, Fe, Zn, Cu and Mn in M. Officinalis leaves was determined by flame atomic absorption speetrometry ( FA AS). [ Result] The content of Ca, Mg, Fe, Zn, Cu and Mn in M. Officinalis leaves was 580. 57, 278.63, 177.21, 16.70, 1.02 and 8.25 mg/kg, respectively. [Conclusion] The FAAS method is simple, rapid and accurate to determine the content of six metal elements in M. Officinalis leaves. The study can provide useful data for exploring the relationship between the content of metal elements and pharmacological actions in M. Officinalis leaves.%[目的]测定厚朴叶中Ca、Mg、Fe、Zn、Cu和Mn 6种金属元素含量.[方法]采用浓硝酸-高氯酸(5∶1,V/V)溶解消化处理样品,火焰原子吸收光谱法测定厚朴叶中Ca、Mg、Fe、Zn、Cu和Mn6种金属元素含量.[结果]厚朴花中Ca、Mg、Fe、Zn、Cu和Mn6种微量元素含量分别为580.57、278.63、177.21、16.7、1.02和8.25 mg/kg.[结论]采用原子吸收光谱法测定厚朴花中金属元素含量,操作简便、快速,结果准确,为探讨厚朴叶中金属元素含量与药理关系提供了有用的数据.

  16. Determination of Calcium, Magnesium, Zinc in Mongolian milk by flame atomic absorption spectrometry%火焰原子吸收法测定蒙古奶茶中的钙、镁、锌

    Institute of Scientific and Technical Information of China (English)

    张金生; 林静; 李丽华; 杨宏娟; 赵文涛

    2012-01-01

    The determination of trace elements in the Mongolian milk tea, such as Calcium, Magnesium and Zinc, was performed by flame atomic absorption spectrometry. The operation conditions were optimized. The Mongolian milk tea was treated by ashing method before determination. The results show that,there is a good linear relationship between the absorbance and concentration of trace elements. The regression equations of Calcium, Magnesium and Zinc are A = 0. 1334C+ 0.0025 (R2 =0.9993),4 = 0. 4838C + 0. 0311 (R2 =0.9998), A = 0. 2149C + 0. 0224 ( R2 =0.9997), respectively. The determination of Calcium, Magnesium and Zinc in three different Mongolian milk teas is carried out. Their RSD values are all lower than 1. 25% and the recovery is around 95. 0% - 105. 0% .%用火焰原子吸收光谱法(FAAS)测定蒙古奶茶中的微量元素钙、镁、锌.对测定条件、干扰因素、准确度和精密度进行了考察.用灰化法处理蒙古奶茶.对3种元素进行测定,结果表明,吸光度与浓度之间呈良好线性关系,钙、镁、锌回归方程分别为:A =0.1334C +0.0025(R2=0.9993),A=0.4838C +0.0311(R2=0.9998),A=0.2149C +0.0224(R2=0.9997).3种不同的蒙古奶茶中的钙、镁、锌测定结果的RSD值均小于1.25%,回收率在95.0%~105.0%.

  17. Application of Box-Behnken design in the optimisation of an on-line pre-concentration system using knotted reactor for cadmium determination by flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Anderson S. [Universidade Federal da Bahia, Instituto de Quimica, Nucleo de Excelencia em Quimica Analitica da Bahia, Campus Universitario de Ondina, Salvador, Bahia 40170-290 (Brazil); Universidade Estadual do Sudoeste da Bahia, Departamento de Quimica e Exatas, Campus de Jequie, Jequie, Bahia 45206-190 (Brazil); Santos, Walter N.L. dos [Universidade Federal da Bahia, Instituto de Quimica, Nucleo de Excelencia em Quimica Analitica da Bahia, Campus Universitario de Ondina, Salvador, Bahia 40170-290 (Brazil); Ferreira, Sergio L.C. [Universidade Federal da Bahia, Instituto de Quimica, Nucleo de Excelencia em Quimica Analitica da Bahia, Campus Universitario de Ondina, Salvador, Bahia 40170-290 (Brazil)]. E-mail: slcf@ufba.br

    2005-06-30

    The present paper proposes an on-line pre-concentration system for cadmium determination in drinking water using flame atomic absorption spectrometry (FAAS). Cadmium(II) ions are retained as 1-(2-pyridylazo)-2-naphthol (PAN) complex at the walls of a knotted reactor, followed of elution using hydrochloric acid solution. The optimization was performed in two steps using factorial design for preliminary evaluation and a Box-Behnken design for determination of the critical experimental conditions. The variables involved were: sampling flow-rate, reagent concentration, pH and buffer concentration, and as response the analytical signal (absorbance). The validation process was performed considering the parameters: linearity and other characteristics of the calibration curve, analytical features of on-line pre-concentration system, precision, effect of other ions in the pre-concentration system and accuracy. Using the optimized experimental conditions, the procedure allows cadmium determination with a detection limit (3 {sigma} / S) of 0.10 {mu}g L{sup -1}, a quantification limit (10 {sigma} / S) of 0.33 {mu}g L{sup -1}, and a precision, calculated as relative standard deviation (RSD) of 2.7% (n = 7) and 2.4% (n = 7) for cadmium concentrations of 5 and 25 {mu}g L{sup -1}, respectively. A pre-concentration factor of 18 and a sampling frequency of 48 h{sup -1} were obtained. The recovery for cadmium in the presence of several ions demonstrated that this procedure could be applied for the analysis of water samples. The method was applied for cadmium determination in drinking water samples collected in Salvador City, Brazil. The cadmium concentrations found in five samples were lower than the maximum permissible levels established by the World Health Organization.

  18. Detection of copper in water using on-line plasma-excited atomic absorption spectroscopy (AAS).

    Science.gov (United States)

    Porento, Mika; Sutinen, Veijo; Julku, Timo; Oikari, Risto

    2011-06-01

    A measurement method and apparatus was developed to measure continuously toxic metal compounds in industrial water samples. The method was demonstrated by using copper as a sample metal. Water was injected into the sample line and subsequently into a nitrogen plasma jet, in which the samples comprising the metal compound dissolved in water were decomposed. The transmitted monochromatic light was detected and the absorbance caused by copper atoms was measured. The absorbance and metal concentration were used to calculate sensitivity and detection limits for the studied metal. The sensitivity, limit of detection, and quantification for copper were 0.45 ± 0.02, 0.25 ± 0.01, and 0.85 ± 0.04 ppm, respectively.

  19. Unusual calibration curves observed for iron using high-resolution continuum source graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Welz, Bernhard, E-mail: w.bernardo@terra.com.b [Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900 Florianopolis-SC (Brazil); Instituto Nacional de Ciencia e Tecnologia do CMPq-INCT de Energia e Ambiente, Universidade Federal da Bahia, 40170-115 Salvador-BA (Brazil); Santos, Lisia M.G. dos [Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900 Florianopolis-SC (Brazil); Instituto Nacional de Controle de Qualidade em Saude-INCQS-Fiocruz, 21040-900 Rio de Janeiro-RJ (Brazil); Araujo, Rennan G.O. [Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900 Florianopolis-SC (Brazil); Departamento de Quimica, Universidade Federal de Sergipe, 49100-000 Sao Cristovao-SE (Brazil); Jacob, Silvana do C. [Instituto Nacional de Controle de Qualidade em Saude-INCQS-Fiocruz, 21040-900 Rio de Janeiro-RJ (Brazil); Vale, Maria Goreti R. [Instituto Nacional de Ciencia e Tecnologia do CMPq-INCT de Energia e Ambiente, Universidade Federal da Bahia, 40170-115 Salvador-BA (Brazil); Instituto de Quimica, Universidade Federal do Rio Grande do Sul, 91501-970 Porto Alegre-RS (Brazil); Okruss, Michael; Becker-Ross, Helmut [Leibniz-Institut fuer Analytische Wissenschaften-ISAS-Department Berlin, 12489 Berlin (Germany)

    2010-03-15

    The simultaneous determination of cadmium and iron in plant and soil samples has been investigated using high-resolution continuum source graphite furnace atomic absorption spectrometry. The primary cadmium resonance line at 228.802 nm and an adjacent secondary iron line at 228.726 nm, which is within the spectral interval covered by the charge-coupled device (CCD) array detector, have been used for the investigations. Due to the very high iron content in most of the soil samples the possibility has been investigated to reduce the sensitivity and extend the working range by using side pixels for measurement at the line wings instead of the line core. It has been found that the calibration curves measured at all the analytically useful pixels of this line consisted of two linear parts with distinctly different slopes. This effect has been independent of the positioning of the wavelength, i.e., if the Cd line or the Fe line was in the center of the CCD array. The most likely explanation for this unusual behavior is a significant difference between the instrument width DELTAlambda{sub Instr} and the absorption line width DELTAlambda{sub Abs}, which is quite pronounced in the case of Fe. Using both parts of the calibration curves and simultaneous measurement at the line center and at the wings made it possible to extend the working range for the iron determination to more than three orders of magnitude.

  20. The response of a neutral atom to a strong laser field probed by transient absorption near the ionisation threshold

    CERN Document Server

    Simpson, E R; Austin, D R; Diveki, Z; Hutchinson, S E E; Siegel, T; Ruberti, M; Averbukh, V; Miseikis, L; Strüber, C; Chipperfield, L; Marangos, J P

    2015-01-01

    We present transient absorption spectra of an extreme ultraviolet attosecond pulse train in helium dressed by an 800 nm laser field with intensity ranging from $2\\times10^{12}$ W/cm$^2$ to $2\\times10^{14}$ W/cm$^2$. The energy range probed spans 16-42 eV, straddling the first ionisation energy of helium (24.59 eV). By changing the relative polarisation of the dressing field with respect to the attosecond pulse train polarisation we observe a large change in the modulation of the absorption reflecting the vectorial response to the dressing field. With parallel polarized dressing and probing fields, we observe significant modulations with periods of one half and one quarter of the dressing field period. With perpendicularly polarized dressing and probing fields, the modulations of the harmonics above the ionisation threshold are significantly suppressed. A full-dimensionality solution of the single-atom time-dependent Schr\\"odinger equation obtained using the recently developed ab-initio time-dependent B-spline...

  1. Determination of Pb(Ⅱ) and Cu(Ⅱ) by Electrothermal Atomic Absorption Spectrometry after Preconcentration by a Schiff Base Adsorbed on Surfactant Coated Alumina

    Institute of Scientific and Technical Information of China (English)

    SABER TEHRANI Mohammad; RASTEGAR Faramarz; PARCHEHBAF Ayob; KHATAMIAN Masoomeh

    2006-01-01

    1,2-Bis(salicylidenamino)ethane loaded onto sodium dodecyl sulfate-coated alumina was used as a new chelating sorbent for the preconcentration of traces of Pb(Ⅱ) and Cu(Ⅱ) prior to atomic absorption spectrometric determination. The influence of pH, flow rates of sample and eluent solutions, and foreign ions on the recovery of Pb(Ⅱ)by electrothermal atomic absorption spectrometry (ETAAS). The data of limit of detection (3σ) for Pb(Ⅱ) and Cu(Ⅱ)posed method was successfully applied to determination of lead and copper in different water samples.

  2. Production mechanism of atomic nitrogen in atmospheric pressure pulsed corona discharge measured using two-photon absorption laser-induced fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Teramoto, Yoshiyuki; Ono, Ryo [Department of Advanced Energy, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 227-8568 (Japan); Oda, Tetsuji [Department of Electrical Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan)

    2012-06-01

    To study the production mechanism of atomic nitrogen, the temporal profile and spatial distribution of atomic nitrogen are measured in atmospheric pressure pulsed positive corona discharge using two-photon absorption laser-induced fluorescence. The absolute atomic nitrogen density in the streamer filaments is estimated from decay rate of atomic nitrogen in N{sub 2} discharge. The results indicate that the absolute atomic nitrogen density is approximately constant against discharge energy. When the discharge voltage is 21.5 kV, production yield of atomic nitrogen produced by an N{sub 2} discharge pulse is estimated to be 2.9 - 9.8 Multiplication-Sign 10{sup 13} atoms and the energy efficiency of atomic nitrogen production is estimated to be about 1.8 - 6.1 Multiplication-Sign 10{sup 16} atoms/J. The energy efficiency of atomic nitrogen production in N{sub 2} discharge is constant against the discharge energy, while that in N{sub 2}/O{sub 2} discharge increases with discharge energy. In the N{sub 2}/O{sub 2} discharge, two-step process of N{sub 2} dissociation plays significant role for atomic nitrogen production.

  3. Determination of total tin in geological materials by electrothermal atomic-absorption spectrophotometry using a tungsten-impregnated graphite furnace

    Science.gov (United States)

    Zhou, L.; Chao, T.T.; Meier, A.L.

    1984-01-01

    An electrothermal atomic-absorption spectrophotometric method is described for the determination of total tin in geological materials, with use of a tungsten-impregnated graphite furnace. The sample is decomposed by fusion with lithium metaborate and the melt is dissolved in 10% hydrochloric acid. Tin is then extracted into trioctylphosphine oxide-methyl isobutyl ketone prior to atomization. Impregnation of the furnace with a sodium tungstate solution increases the sensitivity of the determination and improves the precision of the results. The limits of determination are 0.5-20 ppm of tin in the sample. Higher tin values can be determined by dilution of the extract. Replicate analyses of eighteen geological reference samples with diverse matrices gave relative standard deviations ranging from 2.0 to 10.8% with an average of 4.6%. Average tin values for reference samples were in general agreement with, but more precise than, those reported by others. Apparent recoveries of tin added to various samples ranged from 95 to 111% with an average of 102%. ?? 1984.

  4. Determination of vanadium in urine by electrothermal atomic absorption spectrometry using hot injection and preconcentration into the graphite tube

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, Kelly G.; Nobrega, Joaquim A. [Sao Carlos Univ., SP (Brazil). Dept. de Quimica; Nogueira, Ana Rita A. [Embrapa Pecuaria Sudeste, Sao Carlos, SP (Brazil)]. E-mail: anarita@cppse.embrapa.br; Gomes Neto, Jose A. [UNESP, Araraquara, SP (Brazil). Inst. de Quimica

    2004-10-01

    In this work it was developed a procedure for the determination of vanadium in urine samples by electrothermal atomic absorption spectrometry using successive injections for preconcentration into a preheated graphite tube. Three 60 {mu}L volumes were sequentially injected into the atomizer preheated to a temperature of 110 deg C. Drying and pyrolysis steps were carried out after each injection. A chemical modifier, barium difluoride (100 mg L{sup -1}), and a surfactant, Triton X-100 (0.3% v v{sup -1}), were added to the urine sample. When injecting into a hot graphite tube, the sample flow-rate was 0.5 {mu} s{sup -1}. The limits of detection and quantification were 0.54 and 1.82 without preconcentration, and 0.11 and 0.37 {mu}g L{sup -1} with preconcentration, respectively. The accuracy of the procedure was evaluated by an addition-recovery experiment employing urine samples. Recoveries varied from 96.0 to 103% for additions ranging from 0.8 to 3.5 {mu}g L{sup -1} V. The developed procedure allows the determination of vanadium in urine without any sample pretreatment and with minimal dilution of the sample. (author)

  5. Determination of lead in wine and rum samples by flow injection-hydride generation-atomic absorption spectrometry.

    Science.gov (United States)

    Elçi, Latif; Arslan, Zikri; Tyson, Julian F

    2009-03-15

    A method for direct determination of lead in wine and rum samples was developed, using a flow injection hydride generation system coupled to an atomic absorption spectrometer with flame-quartz atomizer (FI-HG-AAS). Lead hyride (PbH(4)) was generated using potassium ferricyanide (K(3)Fe(CN)(6)), as oxidant and sodium tetrahydroborate (NaBH(4)) as reductant. Samples were acidified to 0.40% (v/v) HCl for wine and to 0.30% (v/v) HCl for rum, which were then mixed on-line with 3% (m/v) K(3)Fe(CN)(6) solution in 0.03% (v/v) HCl prior to reaction with 0.2% (m/v) alkaline NaBH(4) solution. Lead contents of a rum and two different red wine samples were determined by FI-HG-AAS agreed with those obtained by ICP-MS. The analytical figures of merit of method developed were determined. The calibration curve was linear up to 8.0 microg L(-1) Pb with a regression coefficient of 0.998. The relative error was lower than 4.58%. The relative standard deviation (n=7) was better than 12%. A detection limit of 0.16 microg L(-1) was achieved for a sample volume of 170 microL.

  6. Dosage du mercure dans le gaz naturel par absorption atomique sans flammes Mercury Titration in Natural Gas by Flameless Atomic Absorption

    Directory of Open Access Journals (Sweden)

    La Villa F.

    2006-11-01

    Full Text Available Cet article présente la méthode mise au point par l'Institut Français du Pétrole pour déterminer par absorption atomique sans flamme, les traces de mercure métallique contenu dans un gaz naturel. La méthode d'analyse nécessite une extraction du mercure soit sous forme d'ion mercurique en faisant passer le gaz dans une solution oxydante, soit sous forme d'amalgame avec de l'or ou de l'argent. Le premier mode opératoire s'applique aux échantillons dont la concentration en mercure est supérieure à I ttg/Nm3, le second pour des concentrations inférieures à 5 pg/Nm3. Les seuils de détection sont respectivement 10 ng (en solution et 0,3 ng (en amalgame. La répétabilité pour 100 ng de mercure (en amalgame est de ± 7% pour une probabilité de.95 %. En conclusion, dans un échantillon de gaz naturel, compte tenu du volume des prélèvements effectués, il est possible de détecter des concentrations de l'ordre du nanogramme de mercure par mètre cube de gaz. This article describes the method developed by IFP using flameless atomic absorption to determine metallic mercury traces in a natural gas. The analyst method requires a mercury extraction either in the form of mercuric ions by making the gas pass through an oxidizing solution or in the form of an amalgam with gold or silver. The former operating method applies ta samples having a mercury concentration greater than I !ag/Nm3, and the latter for concentrations smaller than 5 (-Lg/Nm3. Detection thresholds are respectively 10 ng (in solution and 0.3 ng (in amalgam. The repeatability for 100 ng of mercury (in amalgam is ± 7 % with a probability of 95%. To conclude, in a sample of natural gas, considering the volume of the samples taken, it is possible ta detect concentrations in the vicinity of one nanogrom of mercury per cubic meter of gas.

  7. Absorption Measurement of Zn Atom Density during ICP-assisted Magnetron Sputter-deposition of Al-doped ZnO Thin Films

    OpenAIRE

    2009-01-01

    This paper reports the outlines of hollow cathode (HCD) lamp absorption system for the density measurement of sputtered metal atoms in the inductively coupled plasma (ICP) assisted sputter-deposition process of Al doped ZnO thin films. As a result, absorbance of about 6.5% was obtained, which corresponds to the Zn atom density of 1.5×1012 cm-3.

  8. Cloud point extraction for the determination of cadmium and lead in biological samples by graphite furnace atomic absorption spectrometry

    Science.gov (United States)

    Maranhão, Tatiane De A.; Borges, Daniel L. G.; da Veiga, Márcia A. M. S.; Curtius, Adilson J.

    2005-06-01

    The phase-separation phenomenon of non-ionic surfactants occurring in aqueous solution was used for the extraction of Cd and Pb from digested biological samples. After complexation with O,O-diethyldithiophosphate (DDTP) in hydrochloric acid medium, the analytes are quantitatively extracted to the phase rich in the non-ionic surfactant octylphenoxypolyethoxyethanol (Triton X-114) after centrifugation. Methanol acidified with 0.1 mol L-1 HNO3 was added to the surfactant-rich phase prior to its analysis by electrothermal atomic absorption spectrometry (ET AAS). The adopted concentrations for DDTP, Triton X-114 and hydrochloric acid were all optimized. Pyrolysis and atomization temperatures were optimized using the extracts and pyrolysis temperatures of 700 °C for both elements and atomization temperatures of 1400 and 1600 °C for cadmium and lead, respectively, were used without adding any modifier, which shows that considerable analyte stabilization is provided by the medium itself. A more detailed investigation was carried out to determine which components of the extract were responsible for the high thermal stability achieved and it revealed that the amount of DDTP added and the phosphorus content of the digested samples contributed significantly to this phenomenon. Detection limits (3σB) of 6 and 40 ng g-1, along with enrichment factors of 129 and 18 for Cd and Pb, respectively, were achieved. The proposed procedure was applied to the analysis of five certified biological reference materials after microwave-assisted acid digestion in a mixture of H2O2 and HNO3. Comparison with certified values was performed for accuracy evaluation, resulting in good agreement according to the t-test for a 95% confidence level. The high efficiency of cloud point extraction to carry out the determination of the studied analytes in complex matrices was, therefore, demonstrated.

  9. Cloud point extraction for the determination of cadmium and lead in biological samples by graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Maranhao, Tatiane de A. [Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil); Borges, Daniel L.G. [Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil)]. E-mail: daniel@qmc.ufsc.br; Veiga, Marcia A.M.S. da [Instituto de Quimica, Universidade de Sao Paulo, 05513-970, CP 26077, Sao Paulo, SP (Brazil); Curtius, Adilson J. [Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil)

    2005-06-30

    The phase-separation phenomenon of non-ionic surfactants occurring in aqueous solution was used for the extraction of Cd and Pb from digested biological samples. After complexation with O,O-diethyldithiophosphate (DDTP) in hydrochloric acid medium, the analytes are quantitatively extracted to the phase rich in the non-ionic surfactant octylphenoxypolyethoxyethanol (Triton X-114) after centrifugation. Methanol acidified with 0.1 mol L{sup -1} HNO{sub 3} was added to the surfactant-rich phase prior to its analysis by electrothermal atomic absorption spectrometry (ET AAS). The adopted concentrations for DDTP, Triton X-114 and hydrochloric acid were all optimized. Pyrolysis and atomization temperatures were optimized using the extracts and pyrolysis temperatures of 700 deg. C for both elements and atomization temperatures of 1400 and 1600 deg. C for cadmium and lead, respectively, were used without adding any modifier, which shows that considerable analyte stabilization is provided by the medium itself. A more detailed investigation was carried out to determine which components of the extract were responsible for the high thermal stability achieved and it revealed that the amount of DDTP added and the phosphorus content of the digested samples contributed significantly to this phenomenon. Detection limits (3{sigma} {sub B}) of 6 and 40 ng g{sup -1}, along with enrichment factors of 129 and 18 for Cd and Pb, respectively, were achieved. The proposed procedure was applied to the analysis of five certified biological reference materials after microwave-assisted acid digestion in a mixture of H{sub 2}O{sub 2} and HNO{sub 3}. Comparison with certified values was performed for accuracy evaluation, resulting in good agreement according to the t-test for a 95% confidence level. The high efficiency of cloud point extraction to carry out the determination of the studied analytes in complex matrices was, therefore, demonstrated.

  10. Mapping atomic and diffuse interstellar band absorption across the Magellanic Clouds and the Milky Way

    CERN Document Server

    Bailey, Mandy; Sarre, Peter J; Beckman, John E

    2015-01-01

    Diffuse interstellar bands (DIBs) trace warm neutral and weakly-ionized diffuse interstellar medium (ISM). Here we present a dedicated, high signal-to-noise spectroscopic study of two of the strongest DIBs, at 5780 and 5797 \\AA, in optical spectra of 666 early-type stars in the Small and Large Magellanic Clouds, along with measurements of the atomic Na\\,{\\sc i}\\,D and Ca\\,{\\sc ii}\\,K lines. The resulting maps show for the first time the distribution of DIB carriers across large swathes of galaxies, as well as the foreground Milky Way ISM. We confirm the association of the 5797 \\AA\\ DIB with neutral gas, and the 5780 \\AA\\ DIB with more translucent gas, generally tracing the star-forming regions within the Magellanic Clouds. Likewise, the Na\\,{\\sc i}\\,D line traces the denser ISM whereas the Ca\\,{\\sc ii}\\,K line traces the more diffuse, warmer gas. The Ca\\,{\\sc ii}\\,K line has an additional component at $\\sim200$--220 km s$^{-1}$ seen towards both Magellanic Clouds; this may be associated with a pan-Magellanic ...

  11. Cosmological evolution of atomic gas and implications for 21 cm HI absorption

    CERN Document Server

    Braun, Robert

    2012-01-01

    Galaxy disks are shown to contain a significant population of atomic clouds of 100pc linear size which are self-opaque in the 21cm transition. These objects have HI column densities as high as 10^23 and contribute to a global opacity correction factor of 1.34+/-0.05 that applies to the integrated 21cm emission to obtain a total HI mass estimate. Opacity-corrected images of the nearest external galaxies have been used to form a robust z=0 distribution function of HI, f(N_HI,X,z=0), the probability of encountering a specific HI column density per unit comoving distance. This is contrasted with previously published determinations of f(N_HI,X) at z=1 and 3. A systematic decline of moderate column density (1820.3) has also declined systematically over this redshift interval by a similar amount, while the cosmological mass density in such systems has declined by only a factor of two to its current, opacity corrected value of Omega_HI^DLA(z=0) = 5.4 +/- 0.9x10^-4. We utilize the tight, but strongly non-linear depend...

  12. Determination of essential elements in beverages, herbal infusions and dietary supplements using a new straightforward sequential approach based on flame atomic absorption spectrometry.

    Science.gov (United States)

    Gómez-Nieto, Beatriz; Gismera, Mª Jesús; Sevilla, Mª Teresa; Procopio, Jesús R

    2017-03-15

    A simple method based on FAAS was developed for the sequential multi-element determination of Cu, Zn, Mn, Mg and Si in beverages and food supplements with successful results. The main absorption lines for Cu, Zn and Si and secondary lines for Mn and Mg were selected to carry out the measurements. The sample introduction was performed using a flow injection system. Using the choice of the absorption line wings, the upper limit of the linear range increased up to 110mgL(-1) for Mg, 200mgL(-1) for Si and 13mgL(-1) for Zn. The determination of the five elements was carried out, in triplicate, without the need of additional sample dilutions and/or re-measurements, using less than 3.5mL of sample to perform the complete analysis. The LODs were 0.008mgL(-1) for Cu, 0.017mgL(-1) for Zn, 0.011mgL(-1) for Mn, 0.16mgL(-1) for Si and 0.11mgL(-1) for Mg.

  13. Determination of serum aluminum by electrothermal atomic absorption spectrometry: A comparison between Zeeman and continuum background correction systems

    Science.gov (United States)

    Kruger, Pamela C.; Parsons, Patrick J.

    2007-03-01

    Excessive exposure to aluminum (Al) can produce serious health consequences in people with impaired renal function, especially those undergoing hemodialysis. Al can accumulate in the brain and in bone, causing dialysis-related encephalopathy and renal osteodystrophy. Thus, dialysis patients are routinely monitored for Al overload, through measurement of their serum Al. Electrothermal atomic absorption spectrometry (ETAAS) is widely used for serum Al determination. Here, we assess the analytical performances of three ETAAS instruments, equipped with different background correction systems and heating arrangements, for the determination of serum Al. Specifically, we compare (1) a Perkin Elmer (PE) Model 3110 AAS, equipped with a longitudinally (end) heated graphite atomizer (HGA) and continuum-source (deuterium) background correction, with (2) a PE Model 4100ZL AAS equipped with a transversely heated graphite atomizer (THGA) and longitudinal Zeeman background correction, and (3) a PE Model Z5100 AAS equipped with a HGA and transverse Zeeman background correction. We were able to transfer the method for serum Al previously established for the Z5100 and 4100ZL instruments to the 3110, with only minor modifications. As with the Zeeman instruments, matrix-matched calibration was not required for the 3110 and, thus, aqueous calibration standards were used. However, the 309.3-nm line was chosen for analysis on the 3110 due to failure of the continuum background correction system at the 396.2-nm line. A small, seemingly insignificant overcorrection error was observed in the background channel on the 3110 instrument at the 309.3-nm line. On the 4100ZL, signal oscillation was observed in the atomization profile. The sensitivity, or characteristic mass ( m0), for Al at the 309.3-nm line on the 3110 AAS was found to be 12.1 ± 0.6 pg, compared to 16.1 ± 0.7 pg for the Z5100, and 23.3 ± 1.3 pg for the 4100ZL at the 396.2-nm line. However, the instrumental detection limits (3

  14. Determination of serum aluminum by electrothermal atomic absorption spectrometry: A comparison between Zeeman and continuum background correction systems

    Energy Technology Data Exchange (ETDEWEB)

    Kruger, Pamela C. [Department of Environmental Health Sciences, School of Public Health, University at Albany, State University of New York, P.O. Box 509, Albany, NY 12201-0509 (United States); Parsons, Patrick J. [Department of Environmental Health Sciences, School of Public Health, University at Albany, State University of New York, P.O. Box 509, Albany, NY 12201-0509 (United States); Lead Poisoning/Trace Elements Laboratory, Wadsworth Center, New York State Department of Health, P.O. Box 509, Albany, NY 12201-0509 (United States)], E-mail: patrick.parsons@wadsworth.org

    2007-03-15

    Excessive exposure to aluminum (Al) can produce serious health consequences in people with impaired renal function, especially those undergoing hemodialysis. Al can accumulate in the brain and in bone, causing dialysis-related encephalopathy and renal osteodystrophy. Thus, dialysis patients are routinely monitored for Al overload, through measurement of their serum Al. Electrothermal atomic absorption spectrometry (ETAAS) is widely used for serum Al determination. Here, we assess the analytical performances of three ETAAS instruments, equipped with different background correction systems and heating arrangements, for the determination of serum Al. Specifically, we compare (1) a Perkin Elmer (PE) Model 3110 AAS, equipped with a longitudinally (end) heated graphite atomizer (HGA) and continuum-source (deuterium) background correction, with (2) a PE Model 4100ZL AAS equipped with a transversely heated graphite atomizer (THGA) and longitudinal Zeeman background correction, and (3) a PE Model Z5100 AAS equipped with a HGA and transverse Zeeman background correction. We were able to transfer the method for serum Al previously established for the Z5100 and 4100ZL instruments to the 3110, with only minor modifications. As with the Zeeman instruments, matrix-matched calibration was not required for the 3110 and, thus, aqueous calibration standards were used. However, the 309.3-nm line was chosen for analysis on the 3110 due to failure of the continuum background correction system at the 396.2-nm line. A small, seemingly insignificant overcorrection error was observed in the background channel on the 3110 instrument at the 309.3-nm line. On the 4100ZL, signal oscillation was observed in the atomization profile. The sensitivity, or characteristic mass (m{sub 0}), for Al at the 309.3-nm line on the 3110 AAS was found to be 12.1 {+-} 0.6 pg, compared to 16.1 {+-} 0.7 pg for the Z5100, and 23.3 {+-} 1.3 pg for the 4100ZL at the 396.2-nm line. However, the instrumental detection

  15. Model calculation of the characteristic mass for convective and diffusive vapor transport in graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Bencs, László, E-mail: bencs.laszlo@wigner.mta.hu [Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, P.O. Box 49, H-1525 Budapest (Hungary); Laczai, Nikoletta [Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, P.O. Box 49, H-1525 Budapest (Hungary); Ajtony, Zsolt [Institute of Food Science, University of West Hungary, H-9200 Mosonmagyaróvár, Lucsony utca 15–17 (Hungary)

    2015-07-01

    A combination of former convective–diffusive vapor-transport models is described to extend the calculation scheme for sensitivity (characteristic mass — m{sub 0}) in graphite furnace atomic absorption spectrometry (GFAAS). This approach encompasses the influence of forced convection of the internal furnace gas (mini-flow) combined with concentration diffusion of the analyte atoms on the residence time in a spatially isothermal furnace, i.e., the standard design of the transversely heated graphite atomizer (THGA). A couple of relationships for the diffusional and convectional residence times were studied and compared, including in factors accounting for the effects of the sample/platform dimension and the dosing hole. These model approaches were subsequently applied for the particular cases of Ag, As, Cd, Co, Cr, Cu, Fe, Hg, Mg, Mn, Mo, Ni, Pb, Sb, Se, Sn, V and Zn analytes. For the verification of the accuracy of the calculations, the experimental m{sub 0} values were determined with the application of a standard THGA furnace, operating either under stopped, or mini-flow (50 cm{sup 3} min{sup −1}) of the internal sheath gas during atomization. The theoretical and experimental ratios of m{sub 0}(mini-flow)-to-m{sub 0}(stop-flow) were closely similar for each study analyte. Likewise, the calculated m{sub 0} data gave a fairly good agreement with the corresponding experimental m{sub 0} values for stopped and mini-flow conditions, i.e., it ranged between 0.62 and 1.8 with an average of 1.05 ± 0.27. This indicates the usability of the current model calculations for checking the operation of a given GFAAS instrument and the applied methodology. - Highlights: • A calculation scheme for convective–diffusive vapor loss in GFAAS is described. • Residence time (τ) formulas were compared for sensitivity (m{sub 0}) in a THGA furnace. • Effects of the sample/platform dimension and dosing hole on τ were assessed. • Theoretical m{sub 0} of 18 analytes were

  16. An expression for the atomic fluorescence and thermal-emission intensity under conditions of near saturation and arbitrary self-absorption

    NARCIS (Netherlands)

    Omenetto, N.; Winefordner, J.D.; Alkemade, C.T.J.

    1975-01-01

    An expression for the effect of self-absorption on the fluorescence and thermal emission intensities is derived by taking into account stimulated emission. A simple, idealized case is considered, consisting of a two level atomic system, in a flame, homogeneous with respect to temperature and composi

  17. Analysis of an Air Conditioning Coolant Solution for Metal Contamination Using Atomic Absorption Spectroscopy: An Undergraduate Instrumental Analysis Exercise Simulating an Industrial Assignment

    Science.gov (United States)

    Baird, Michael J.

    2004-01-01

    A real-life analytical assignment is presented to students, who had to examine an air conditioning coolant solution for metal contamination using an atomic absorption spectroscopy (AAS). This hands-on access to a real problem exposed the undergraduate students to the mechanism of AAS, and promoted participation in a simulated industrial activity.

  18. International comparison of Cd content in a quality control material of Navajuelas (Tagelus dombeii) determined by anodic stripping voltammetry, atomic absorption spectrometry and neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Queirolo, F. (Universidad Catolica del Norte, Antofagasta (Chile). Dept. of Chemistry Forschungszentrum Juelich GmbH (Germany, F.R.). Inst. fuer Angewandte Physikalische Chemie Universidad de Extremadura, Badajoz (Spain). Dept. of Analytical Chemistry and Electrochemistry); Ostapczuk, P. (Forschungszentrum Juelich GmbH (Germany, F.R.). Inst. fuer Angewandte Physikalische Chemie); Valenta, P.; Stegen, S. (Forschungszentrum Juelich GmbH (Germany, F.R.). Inst. fuer Angewandte Physikalische Chemie Universidad de Extremadura, Badajoz (Spain). Dept. of Analytical Chemistry and Electrochemistry); Marin, C.; Vinagre, F.; Sanchez, A. (Universidad de Extremadura, Badajoz (Spain). Dept. of Analytical Chemistry and Electrochemistry)

    1991-05-01

    The determination of Cd was performed by neutron activation analysis (NAA), atomic absorption spectrometry (AAS) with flame or in the electrothermal mode and anodic stripping voltammetry in the differential pulse mode (DPASV) and the square wave mode (SWASV). (orig./EF).

  19. Determination of arsenic in liver and kidney of mice exposed in realgar by HG-FAAS%HG-FAAS 法测定雄黄染毒小鼠肝及肾脏中的砷含量

    Institute of Scientific and Technical Information of China (English)

    苑洁; 霍韬光; 王艳蕾; 郭婧潭; 焦雪鑫; 张颖花; 袁媛; 高岚岳; 姜泓

    2015-01-01

    A novel hydride generation‐flame atomic absorption spectrometry (HG‐FAAS ) method was established for the determination of arsenic in liver and kidney of mice after realgar exposure .The results showed that the method was accurate ,sensitive ,reliable and low detec‐tion limit .The distribution levels of arsenic in liver ,kidney of realgar infected mice were fairly with the liver and kidney content .Meanwhile hydride generation conditions were optimized .%建立了氢化物发生‐火焰原子吸收法(HG‐FAAS)测定雄黄染毒小鼠肝及肾脏中砷含量的方法。结果表明,该方法准确、灵敏、可靠、检出限低。雄黄染毒小鼠肝、肾脏中砷的分布水平相当。同时对氢化物发生条件进行了优化。

  20. X-ray photoelectron spectroscopy study of pyrolytically coated graphite platforms submitted to simulated electrothermal atomic absorption spectrometry conditions

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz, Frine [Laboratorio de Quimica Analitica, Centro de Quimica, Instituto Venezolano de Investigaciones Cientificas, IVIC, Apartado Postal 21827, Caracas 1020-A (Venezuela); Benzo, Zully [Laboratorio de Quimica Analitica, Centro de Quimica, Instituto Venezolano de Investigaciones Cientificas, IVIC, Apartado Postal 21827, Caracas 1020-A (Venezuela); Quintal, Manuelita [Laboratorio de Quimica Analitica, Centro de Quimica, Instituto Venezolano de Investigaciones Cientificas, IVIC, Apartado Postal 21827, Caracas 1020-A (Venezuela); Garaboto, Angel [Laboratorio de Quimica Analitica, Centro de Quimica, Instituto Venezolano de Investigaciones Cientificas, IVIC, Apartado Postal 21827, Caracas 1020-A (Venezuela); Albornoz, Alberto [Laboratorio de Fisicoquimica de Superficies, Centro de Quimica, Instituto Venezolano de Investigaciones Cientificas, IVIC, Apartado Postal 21827, Caracas 1020-A (Venezuela); Brito, Joaquin L. [Laboratorio de Fisicoquimica de Superficies, Centro de Quimica, Instituto Venezolano de Investigaciones Cientificas, IVIC, Apartado Postal 21827, Caracas 1020-A (Venezuela)]. E-mail: joabrito@ivic.ve

    2006-10-15

    The present work is part of an ongoing project aiming to a better understanding of the mechanisms of atomization on graphite furnace platforms used for electrothermal atomic absorption spectrometry (ETAAS). It reports the study of unused pyrolytic graphite coated platforms of commercial origin, as well as platforms thermally or thermo-chemically treated under simulated ETAAS analysis conditions. X-ray photoelectron spectroscopy (XPS) was employed to study the elements present at the surfaces of the platforms. New, unused platforms showed the presence of molybdenum, of unknown origin, in concentrations up to 1 at.%. Species in two different oxidations states (Mo{sup 6+} and Mo{sup 2+}) were detected by analyzing the Mo 3d spectral region with high resolution XPS. The analysis of the C 1s region demonstrated the presence of several signals, one of these at 283.3 eV related to the presence of Mo carbide. The O 1s region showed also various peaks, including a signal that can be attributed to the presence of MoO{sub 3}. Some carbon and oxygen signals were consistent with the presence of C=O and C-O- (probably C-OH) groups on the platforms surfaces. Upon thermal treatment up to 2900 deg. C, the intensity of the Mo signal decreased, but peaks due to Mo oxides (Mo{sup 6+} and Mo{sup 5+}) and carbide (Mo{sup 2+}) were still apparent. Thermo-chemical treatment with 3 vol.% HCl solutions and heating up to 2900 deg. C resulted in further diminution of the Mo signal, with complete disappearance of Mo carbide species. Depth profiling of unused platforms by Ar{sup +} ion etching at increasing time periods demonstrated that, upon removal of several layers of carbonaceous material, the Mo signal disappears suggesting that this contamination is present only at the surface of the pyrolytic graphite platform.

  1. Determination of platinum traces contamination by graphite furnace atomic absorption spectrometry after preconcentration by cloud point extraction

    Energy Technology Data Exchange (ETDEWEB)

    Chappuy, M. [Analytical Development Laboratory, Pharmaceutical Establishment of Paris Hospitals, 7 rue du Fer a Moulin, 75005 Paris (France); Caudron, E., E-mail: eric.caudron@eps.aphp.fr [Analytical Development Laboratory, Pharmaceutical Establishment of Paris Hospitals, 7 rue du Fer a Moulin, 75005 Paris (France); Groupe de Chimie Analytique de Paris-Sud, EA 4041, IFR 141, School of Pharmacy, Univ Paris-Sud, 92296 Chatenay-Malabry (France); Bellanger, A. [Department of Pharmacy, Pitie-Salpetriere Hospital (Paris Public Hospital Authority), 47 boulevard de l' hopital, 75013 Paris (France); Pradeau, D. [Analytical Development Laboratory, Pharmaceutical Establishment of Paris Hospitals, 7 rue du Fer a Moulin, 75005 Paris (France)

    2010-04-15

    A simple and sensitive method is described for the determination of platinum surface contamination originating from cisplatin, carboplatin and oxaliplatin. Following extraction from swabs and preconcentration with the cloud point extraction (CPE) method, detection was by graphite furnace atomic absorption spectrometry (GFAAS). After desorption of platinum compounds from the swab, CPE involved on preconcentration of platinum in aqueous solution with diethyldithiocarbamate (DDTC) as chelating agent and Triton X-114 as extraction medium. DDTC is not only a chelating agent, but may also be a good candidate for the inactivation of platinum compounds. DDTC is recommended by the Word Health Organization (WHO) for the destruction of platinum-based anticancer drugs. The main factors affecting CPE efficiency, pH of the sample solution, concentrations of DDTC and Triton X-114, equilibration temperature and incubation time, were evaluated in order to enhance sensitivity of the method. The desorption of platinum compounds from the swab was investigated in parallel. Since platinum is bound to DDTC, it must exchange with copper in order to enhance platinum atomizing by GFAAS. A preconcentration factor of 29 was obtained for 10 mL of a platinum solution at 10 {mu}g mL{sup -1}. In optimal conditions, the limit of detection was 0.2 ng mL{sup -1}, corresponding to 2.0 ng of platinum metal on the swab. Absorbance was linear between 0.7 and 15 ng mL{sup -1}. The proposed method was applied for the determination of surface contamination by platinum compounds with correct results.

  2. UV-photochemical vapor generation of selenium for atomic absorption spectrometry: Optimization and 75Se radiotracer efficiency study

    Science.gov (United States)

    Rybínová, Marcela; Musil, Stanislav; Červený, Václav; Vobecký, Miloslav; Rychlovský, Petr

    2016-09-01

    Volatile selenium compounds were generated UV-photochemically in the continuous flow mode using four UV-photoreactors differing in the material of the reaction coil; Teflon tubing and quartz tubes with various inner diameters and wall thicknesses were tested. Atomic absorption spectrometry with an externally heated quartz furnace atomizer was employed as the detector. The relevant experimental generation parameters were optimized and the basic analytical characteristics were determined. Using formic acid as the photochemical agent, limits of detection achieved for selenium were in the range 46-102 ng L- 1 in dependence on the type of UV-photoreactor employed. When nitric acid was also added to the photochemical agent, the limits of detection were reduced to 27-44 ng L- 1. The repeatability did not exceed 2.4% (5 μg L- 1 Se(IV), n = 10). Experiments with 75Se radiotracer have been performed for the first time to quantify the efficiency of UV-photochemical vapor generation (UV-PVG) of selenium. The highest efficiency of 67 ± 1% was obtained for a UV-photoreactor containing a quartz reaction coil (2.0 mm i.d., 4.0 mm o.d.). The generation efficiency of 61 ± 1% was obtained for a Teflon reaction coil (1.0 mm i.d., 1.4 mm o.d.). Mapping of the radiotracer distribution in the individual parts of the apparatus did not reveal substantial transport losses of the analyte in the UV-PVG system.

  3. Determination of some trace metals by FAAS after solid-phase extraction with amberlite XAD-1180/TAN chelating resin.

    Science.gov (United States)

    Yilmaz, Vedat; Kartal, Senol

    2012-01-01

    A new chelating resin was synthesized by immobilizing 1-(2-thiazolylazo)-2-naphthol through the -N=N- group on Amberlite XAD-1180. The resin was used for the preconcentration of Cd(II), Co(II), Cu(II), Mn(II), Ni(II), and Pb(II) ions and their determination by flame atomic absorption spectrometry (FAAS). The influences of some analytical parameters, such as the pH, volume of the sample, flow rates of the sample and eluent, matrix components, amount of the resin, and amount and type of the eluent on the recovery, were investigated. Those metals retained on the resin at pH 8.5 were eluted with 25 mL of 2 mol L(-1) HNO(3). The sorption capacity of the resin was determined, except for Pb(II). The recoveries were found to be ≥95%, and the relative standard-deviation values were ≤4.3%. The detection limits were in the range of 0.1 - 3.6 µg L(-1). For the accuracy of the method, the analysis of a certified reference material was performed. This method was applied to environmental water samples.

  4. Determination of aluminum by electrothermal atomic absorption spectroscopy in lubricating oils emulsified in a sequential injection analysis system.

    Science.gov (United States)

    Burguera, José L; Burguera, Marcela; Antón, Raquel E; Salager, Jean-Louis; Arandia, María A; Rondón, Carlos; Carrero, Pablo; de Peña, Yaneira Petit; Brunetto, Rosario; Gallignani, Máximo

    2005-12-15

    The sequential injection (SIA) technique was applied for the on-line preparation of an "oil in water" microemulsion and for the determination of aluminum in new and used lubricating oils by electrothermal atomic absorption spectrometry (ET AAS) with Zeeman-effect background correction. Respectively, 1.0, 0.5 and 1.0ml of surfactants mixture, sample and co-surfactant (sec-butanol) solutions were sequentially aspirated to a holding coil. The sonication and repetitive change of the flowing direction improved the stability of the different emulsion types (oil in water, water in oil and microemulsion). The emulsified zone was pumped to fill the sampling arm of the spectrometer with a sub-sample of 200mul. Then, 10mul of this sample solution were introduced by means of air displacement in the graphite tube atomizer. This sequence was timed to synchronize with the previous introduction of 15mug of Mg(NO(3))(2) (in a 10mul) by the spectrometer autosampler. The entire SIA system was controlled by a computer, independent of the spectrometer. The furnace program was carried out by employing a heating cycle in four steps: drying (two steps at 110 and 130 degrees C), pyrolisis (at 1500 degrees C), atomization (at 2400 degrees C) and cleaning (at 2400 degrees C). The calibration graph was linear from 7.7 to 120mugAll(-1). The characteristic mass (mo) was 33.2pg/0.0044s and the detection limit was 2.3mugAll(-1). The relative standard (RSD) of the method, evaluated by replicate analyses of different lubricating oil samples varied in all cases between 1.5 and 1.7%, and the recovery values found in the analysis of spiked samples ranged from 97.2 to 100.4%. The agreement between the observed and reference values obtained from two NIST Standard Certified Materials was good. The method was simple and satisfactory for determining aluminum in new and used lubricating oils.

  5. Investigation of the levels of some element in edible oil samples produced in Turkey by atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Mendil, Durali, E-mail: dmendil@gop.edu.tr [Gaziosmanpasa University, Faculty of Science and Arts, Chemistry Department, 60250 Tokat (Turkey); Uluoezlue, Ozguer Dogan; Tuezen, Mustafa [Gaziosmanpasa University, Faculty of Science and Arts, Chemistry Department, 60250 Tokat (Turkey); Soylak, Mustafa [Erciyes University, Faculty of Science and Arts, Department of Chemistry, 38039 Kayseri (Turkey)

    2009-06-15

    The element contents (Fe, Mn, Zn, Cu, Pb, Co, Cd, Na, K, Ca and Mg) in edible oils (olive oil, hazelnut oil, sunflower oil, margarine, butter and corn oil) from Turkey were determined using atomic absorption spectrometry after microwave digestion. The concentrations of trace element in the samples were found to be 291.0-52.0, 1.64-0.04, 3.08-1.03, 0.71-0.05, 0.03-0.01, 1.30-0.50, 84.0-0.90, 50.1-1.30, 174.2-20.8 and 20.8-0.60 {mu}g/g for iron, manganese, zinc, copper, lead, cobalt, sodium, potassium, calcium, and magnesium, respectively. Cadmium was found to be 4.57-0.09 {mu}g/kg. The high heavy metal and minerals accumulation levels in the samples were found in olive oil for Cu, Pb, Co, margarine for Fe, K, corn oil for Zn, Mn, butter for Na, Mg, sunflower oil for Ca and hazelnut oil for Cd, respectively.

  6. Determination of trace nickel in hydrogenated cottonseed oil by electrothermal atomic absorption spectrometry after microwave-assisted digestion.

    Science.gov (United States)

    Zhang, Gai

    2012-01-01

    Microwave digestion of hydrogenated cottonseed oil prior to trace nickel determination by electrothermal atomic absorption spectrometry (ETAAS) is proposed here for the first time. Currently, the methods outlined in U.S. Pharmacopeia 28 (USP28) or British Pharmacopeia (BP2003) are recommended as the official methods for analyzing nickel in hydrogenated cottonseed oil. With these methods the samples may be pre-treated by a silica or a platinum crucible. However, the samples were easily tarnished during sample pretreatment when using a silica crucible. In contrast, when using a platinum crucible, hydrogenated cottonseed oil acting as a reducing material may react with the platinum and destroy the crucible. The proposed microwave-assisted digestion avoided tarnishing of sample in the process of sample pretreatment and also reduced the cycle of analysis. The programs of microwave digestion and the parameters of ETAAS were optimized. The accuracy of the proposed method was investigated by analyzing real samples. The results were compared with the ones by pressurized-PTFE-bomb acid digestion and ones obtained by the U.S. Pharmacopeia 28 (USP28) method. The new method involves a relatively rapid matrix destruction technique compared with other present methods for the quantification of metals in oil.

  7. Determination of ultra-trace aluminum in human albumin by cloud point extraction and graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Sun Mei, E-mail: sunmei@ustc.edu.cn [Hefei National Laboratory for Physical Sciences on Microscale, University of Science and Technology of China, No. 96, Jinzhai Road, Hefei 230026 (China); Wu Qianghua [Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026 (China)

    2010-04-15

    A cloud point extraction (CPE) method for the preconcentration of ultra-trace aluminum in human albumin prior to its determination by graphite furnace atomic absorption spectrometry (GFAAS) had been developed in this paper. The CPE method was based on the complex of Al(III) with 1-(2-pyridylazo)-2-naphthol (PAN) and Triton X-114 was used as non-ionic surfactant. The main factors affecting cloud point extraction efficiency, such as pH of solution, concentration and kind of complexing agent, concentration of non-ionic surfactant, equilibration temperature and time, were investigated in detail. An enrichment factor of 34.8 was obtained for the preconcentration of Al(III) with 10 mL solution. Under the optimal conditions, the detection limit of Al(III) was 0.06 ng mL{sup -1}. The relative standard deviation (n = 7) of sample was 3.6%, values of recovery of aluminum were changed from 92.3% to 94.7% for three samples. This method is simple, accurate, sensitive and can be applied to the determination of ultra-trace aluminum in human albumin.

  8. Cloud point extraction-flame atomic absorption spectrometry method for preconcentration and determination of trace cadmium in water samples.

    Science.gov (United States)

    Ning, Jinyan; Jiao, Yang; Zhao, Jiao; Meng, Lifen; Yang, Yaling

    2014-01-01

    A method based on cloud point extraction (CPE) separation/preconcentration of trace cadmium (Cd) as a prior step to its determination by flame atomic absorption spectrometry has been developed. Cadmium reacted with 8-hydroxyquinoline to form hydrophobic chelates, which were extracted into the micelles of nonionic surfactant oligoethylene glycol monoalkyl ether (Genapol X-080) in an alkaline medium. Octanol was used to depress the cloud point of Genapol X-080 in the extraction process. The chemical variables that affect the CPE, such as pH of complexation reaction, amount of chelating agent, Genapol X-080 and octanol were evaluated and optimized. Under optimized conditions, linearity was obeyed in the range of 10-500 μg/L, with the correlation coefficient of 0.9993. For 5 mL of sample solution, the enhancement factor was about 20. The limit of detection and limit of quantification of the method were 0.21 and 0.63 μg/L, respectively. The relative standard deviations (n = 6) was 3.2% for a solution containing 100 μg/L of Cd. The accuracy of the preconcentration system was evaluated by recovery measurements on spiked water samples. Recoveries of spiked samples varied in the range of 94.1-103.8%.

  9. Determination of trace nickel in water samples by cloud point extraction preconcentration coupled with graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Sun Zhimei [Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079 (China); Department of Chemistry and Biology, Huainan Normal University, Huainan 232001 (China); Liang Pei [Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079 (China)]. E-mail: liangpei@mail.ccnu.edu.cn; Ding Qiong [Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079 (China); Cao Jing [Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079 (China)

    2006-09-21

    A new method based on the cloud point extraction (CPE) preconcentration and graphite furnace atomic absorption spectrometry (GFAAS) detection was proposed for the determination of trace nickel in water samples. When the micelle solution temperature is higher than the cloud point of surfactant p-octylpolyethyleneglycolphenyether (Triton X-100), the complex of Ni{sup 2+} with 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) could enter surfactant-rich phase and be concentrated, then determined by GFAAS. The main factors affecting the cloud point extraction were investigated in detail. An enrichment factor of 27 was obtained for the preconcentration of Ni{sup 2+} with 10 mL solution. Under the optimal conditions, the detection limit of Ni{sup 2+} is 0.12 ng mL{sup -1} with R.S.D. of 4.3% (n = 10, c = 100 ng mL{sup -1}). The proposed method was applied to determination of trace nickel in water samples with satisfactory results.

  10. Two-photon absorption laser induced fluorescence measurement of atomic oxygen density in an air atmospheric pressure plasma jet

    Science.gov (United States)

    Conway, Jim; Gogna, Gurusharan; Daniels, Stephen

    2016-09-01

    Two-photon Absorption Laser Induced Fluorescence (TALIF) is used to measure atomic oxygen number density [O] in an air Atmospheric Pressure Plasma Jet (APPJ). A novel technique based on photolysis of O2 is used to calibrate the TALIF system ensuring the same species (O) is probed during calibration and measurement. As a result, laser intensity can be increased outside the TALIF quadratic laser power region without affecting calibration reliability as any high intensity saturation effects will be identical for calibration and experiment. Higher laser intensity gives stronger TALIF signals helping overcome weak TALIF signals often experienced at atmospheric pressure due to collisional quenching. O2 photo-dissociation and two-photon excitation of the resulting [O] are both achieved within the same laser pulse. The photolysis [O] is spatially non-uniform and time varying. To allow valid comparison with [O] in a plasma, spatial and temporal correction factors are required. Knowledge of the laser pulse intensity I0(t), and wavelength allows correction factors to be found using a rate equation model. The air flow into the jet was fixed and the RF power coupled into the system varied. The resulting [O] was found to increase with RF power.

  11. The determination of wear metals in used lubricating oils by flame atomic absorption spectrometry using sulphanilic acid as ashing agent.

    Science.gov (United States)

    Ekanem, E J; Lori, J A; Thomas, S A

    1997-11-01

    A simple and reliable ashing procedure is proposed for the preparation of used lubricating oil samples for the determination of calcium, magnesium, zinc, iron, chromium and nickel by flame atomic absorption spectrometry. Sulphanilic acid was added to oil samples and the mixture coked and the coke ashed at 550 degrees C. The solutions of the ash were analysed by flame AAS for the metals. The release of calcium, zinc, iron and chromium was improved by the addition of sulphanilic acid to samples. The relative standard deviations of metal concentration results in the initial oil samples were 1.5% for Ca (1500 mg l(-1) level), 0.3% for Mg (100 mg l(-1) level), 3.1% for Zn (1500 mg l(-1) level), 0.7% for Fe (500 mg l(-1) level), 0.02% for Cr (50 mg l(-1) level) and 0.002% for Ni (10 mg l(-1) level). The optimum sample size for efficient metal release was 20 g while the optimum sulphanilic acid to oil ratio was 0.05 g per gram of oil for Zn and Cr and 0.10 g for Ca and Fe. Results obtained by this procedure were highly reproducible and comparable with those obtained for the same samples using standard procedures.

  12. Trace metal characterization and speciation in geothermal effluent by multiple scanning anodic stripping voltammetry and atomic absorption analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kowalski, B.R.

    1979-05-25

    Recent studies have shown geothermal power plants to have a significant environmental impact on the ground water of the area. The heavy metals arsenic and mercury are special problems, as both are concentrated by flora and fauna exposed to the effluent waters. Because the toxicity of these and other metallic pollutants present in geothermal effluent depends on the chemical form, or speciation, of the particular metal, any serious study of the environmental impact of a geothermal development should include studies of trace metal speciation, in addition to trace metal concentration. This proposal details a method for determining metal speciation in dilute waters. The method is based on ion-exchange and backed by atomic absorption spectrometry and multiple scanning anodic stripping voltammetry. Special laboratory studies will be performed on mercury, arsenic and selenium speciation in synthetic geothermal water. The method will be applied to three known geothermal areas in Washington and Oregon, with emphasis on the speciation of mercury, arsenic and selenium in these waters. The computer controlled electrochemical instrumentation was built and tested. Using this instrumentation, a new experimental procedure was developed to determine the chemical form (speciation) of metal ions in very dilute solutions (ng/ml). This method was tested on model systems including Pb, Cd, and As with C1/sup -/, CO/sub 3//sup 2 -/ and glycine ligands. Finally, the speciation of lead in a geothermal water was examined and the PbC1/sup +/ complex was observed and quantified.

  13. Determination of total arsenic in coal and wood using oxygen flask combustion method followed by hydride generation atomic absorption spectrometry.

    Science.gov (United States)

    Geng, Wenhua; Furuzono, Takuya; Nakajima, Tsunenori; Takanashi, Hirokazu; Ohki, Akira

    2010-04-15

    A simple and sensitive procedure for the determination of total arsenic in coal and wood was conducted by use of oxygen flask combustion (OFC) followed by hydride generation atomic absorption spectrometry (HGAAS). The effect of various items (composition of absorbent, standing time between the combustion and filtration, particle size and mass of sample) was investigated. Under the optimized conditions of the OFC method, nine certified reference materials were analyzed, and the values of arsenic concentration obtained by this method were in good accordance with the certified values. The limit of detection (LOD) and relative standard deviation (RSD) of the method were 0.29 microg g(-1) and less than 8%, respectively. In addition, eight kinds of coals and four chromated copper arsenate (CCA)-treated wood wastes were analyzed by the present method, and the data were compared to those from the microwave-acid digestion (MW-AD) method. The determination of arsenic in solid samples was discussed in terms of applicable scope and concentration range of arsenic.

  14. Evaluation of arsenic, cobalt, copper and manganese in biological Samples of Steel mill workers by electrothermal atomic absorption Spectrometry.

    Science.gov (United States)

    Afridi, H I; Kazi, T G; Kazi, N G; Jamali, M K; Arain, M B; Sirajuddin; Kandhro, G A; Shah, A Q; Baig, J A

    2009-02-01

    The determination of trace and toxic elements in biological samples (blood, urine and scalp hair samples) of human beings is an important clinical test. The aim of our present study was to determine the concentration of arsenic (As), copper (Cu), cobalt (Co) and manganese (Mn), in biological samples of male production workers (PW) and quality control workers (QW) of steel mill, with aged 25-55 years, to assess the possible influence of environmental exposure. For comparison purpose, the same biological samples of unexposed healthy males of same age group were collected as control subjects. The determination of all elements in biological samples was carried out by electrothermal atomic absorption spectrometry, prior to microwave assisted acid digestion. The accuracy of the As, Cu, Co and Mn measurements was tested by simultaneously analyzing certified reference materials (CRMs) and for comparative purposes conventional wet acid digestion method was used on the same CRMs. No significant differences were observed between the analytical results and the certified values, using both methods (paired t-test at P > 0.05). The results indicate that concentrations of As, Cu, Co and Mn in all three biological samples of the exposed workers (QW and PW) were significantly higher than those of the controls. The possible correlation of these elements with the etiology of different physiological disorders is discussed. The results were also demonstrated the need of attention for improvements in workplace, ventilation and industrial hygiene practices.

  15. [Determination of trace elements in Lophatherum gracile brongn from different habitat by microwave digestion-atomic absorption spectroscopy].

    Science.gov (United States)

    Yuan, Ke; Xue, Yue-Qin; Gui, Ren-Yi; Sun, Su-Qin; Yin, Ming-Wen

    2010-03-01

    A method of microwave digestion technique was proposed to determine the content of Zn, Fe, Cu, Mn, K, Ca, Mg, Ni, Cd, Pb, Cr, Co, Al, Se and As in Lophatherum gracile brongn of different habitat by atomic absorption spectroscopy. The RSD of the method was between 1.23% and 3.32%, and the recovery rates obtained by standard addition method were between 95.8% and 104.20%. The results of the study indicate that the proposed method has the advantages of simplicity, speediness and sensitivity. It is suitable for the determination of the contents of metal elements in Lophatherum gracile brongn. The experimental results also indicated that different areas' Lophantherum gracile brongn had different trace elements content. The content of trace elements K, Mg, Ca, Fe and Mn beneficial to the human body was rich. The content of the heavy metal trace element Pb in Lophantherum gracile brongn of Hunan province was slightly high. The content of the heavy metal trace element Cu in Lophantherum gracile brongn of Guangdong province and Anhui province is also slightly higher. Beside, the contents of harmful trace heavy metal elements Cd, Cu, Cr, Pb and As in Lophatherum gracile brongn of different habitat are all lower than the limits of Chinese Pharmacopoeia and Green Trade Standard for Importing and Exporting Medicinal Plant and Preparation and National Food Sanitation Standard. These determination results provided the scientific data for further discussing the relationship between the content of trace elements in Lophantherum gracile brongn and the medicine efficacy.

  16. Comparison of selenium determination in liver samples by atomic absorption spectroscopy and inductively coupled plasma-mass spectrometry.

    Science.gov (United States)

    Miksa, Irina Rudik; Buckley, Carol L; Carpenter, Nancy P; Poppenga, Robert H

    2005-07-01

    Selenium (Se) is an essential trace element that is often deficient in the natural diets of domestic animal species. The measurement of Se in whole blood or liver is the most accurate way to assess Se status for diagnostic purposes. This study was conducted to compare hydride generation atomic absorption spectroscopy (HG-AAS) with inductively coupled plasma-mass spectrometry (ICP-MS) for the detection and quantification of Se in liver samples. Sample digestion was accomplished with magnesium nitrate and nitric acid for HG-AAS and ICP-MS, respectively. The ICP-MS detection was optimized for 82Se with yttrium used as the internal standard and resulted in a method detection limit of 0.12 microg/g. Selenium was quantified by both methods in 310 samples from a variety of species that were submitted to the Toxicology Laboratory at New Bolton Center (Kennett Square, PA) for routine diagnostic testing. Paired measurements for each sample were evaluated by a mean difference plot method. Limits of agreement were used to describe the maximum differences likely to occur between the 2 methods. Results suggest that under the specified conditions ICP-MS can be reliably used in place of AAS for quantitation of tissue Se at or below 2 microg/g to differentiate between adequate and deficient liver Se concentrations.

  17. Standardization and validation of a new atomic absorption spectroscopy technique for determination and quantitation of aluminium adjuvant in immunobiologicals.

    Science.gov (United States)

    Mishra, Arti; Bhalla, Sumir Rai; Rawat, Sameera; Bansal, Vivek; Sehgal, Rakesh; Kumar, Sunil

    2007-10-01

    In the present study, Aluminium quantification in immunobiologicals has been described using atomic absorption spectroscopy (AAS) technique. The assay was found to be linear in 25-125 microg/ml Aluminium range. The procedure was found to be accurate for different vaccines with recoveries of external additions ranging between 93.26 and 103.41%. The mean Limit of Variation (L.V.) for both intra- and inter-assay precision was calculated to be 1.62 and 2.22%, respectively. Further the procedure was found to be robust in relation to digestion temperature, alteration in acid (HNO(3) and H(2)SO(4)) ratio used for sample digestion and storage of digested vaccine samples up to a period of 15 days. After validation, AAS method was compared for its equivalency with routinely used complexometric titration method. On simultaneously applying on seven different groups of both bacterial and viral vaccines, viz., DPT, DT, TT, Hepatitis-A and B, Antirabies vaccine (cell culture) and tetravalent DPT-Hib, a high degree of positive correlation (+0.85-0.998) among AAS and titration methods was observed. Further AAS method was found to have an edge over complexometric titration method that a group of vaccines, viz., ARV (cell culture, adsorbed) and Hepatitis-A, in which Aluminium estimation is not feasible by pharmacopoeial approved complexometric titration method (possibly due to some interference in the sample matrix), this newly described and validated AAS assay procedure delivered accurate and reproducible results.

  18. Immersed single-drop microextraction-electrothermal vaporization atomic absorption spectroscopy for the trace determination of mercury in water samples.

    Science.gov (United States)

    Bagheri, Habib; Naderi, Mehrnoush

    2009-06-15

    A new method based on single-drop microextraction (SDME) combined with electrothermal vaporization atomic absorption spectroscopy (ETV-AAS) was developed for the trace determination of mercury in water samples. A microdrop of m-xylene was applied as the extraction solvent. After extraction, the microdrop was introduced, directly, into a graphite furnace of AAS. Some important extraction parameters such as type of solvent, volume of solvent, sample stirring, ionic strength, sample pH, chelating agent concentration, sample temperature, and extraction time were investigated and optimized. The highest possible microdrop volume of 10 microL, a sampling temperature of 27 degrees C, and use of m-xylene containing dithizone, as complexing agent, are major parameters led to achieve a high enrichment factor of 970. Under the optimized conditions, the detection limit of the method was 0.01 microg L(-1) and the relative standard deviation was 6.1% (n=7). The proposed method has been successfully applied to the determination of Hg in two river water samples. The effects of interfering species such as Pt, Pd, Cu, Au, and Bi, having the tendency to form complexes with dithizone, at two concentration levels of 100 and 1000 microg L(-1) were also studied.

  19. Determination of heavy metal contents by atomic absorption spectroscopy (AAS) in some medicinal plants from Pakistani and Malaysian origin.

    Science.gov (United States)

    Akram, Sobia; Najam, Rahila; Rizwani, Ghazala H; Abbas, Syed Atif

    2015-09-01

    This study depicts a profile of existence of heavy metals (Cu, Ni, Zn, Cd, Hg, Mn, Fe, Na, Ca, and Mg) in some important herbal plants like (H. Integrifolia, D. regia, R. communis, C. equisetifolia, N. oleander, T. populnea, M. elengi, H. schizopetalus, P. pterocarpum) from Pakistan and an antidiabetic Malaysian herbal drug product containing (Punica granatum L. (Mast) Hook, Momordica charantia L., Tamarindus indica L., Lawsonia inermis L.) using atomic absorption spectrophotometer. Heavy metals in these herbal plants and Malaysian product were in the range of 0.02-0.10 ppm of Cu, 0.00-0.02 ppm of Ni, 0.02-0.29 ppm of Zn, 0.00-0.04 ppm of Cd, 0.00-1.33 ppm of Hg, 0.00-0.54 ppm of Mn, 0.22-3.16 ppm of Fe, 0.00-9.17 ppm of Na, 3.27-15.63 ppm of Ca and 1.85-2.03 ppm of Mg. All the metals under study were within the prescribed limits except mercury. Out of 10 medicinal plants/product under study 07 were beyond the limit of mercury permissible limits. Purpose of this study is to determine heavy metals contents in selected herbal plants and Malaysian product, also to highlight the health concerns related to the presence of toxic levels of heavy metals.

  20. Non-patchy strategy for inter-atomic distances from Extended X-ray Absorption Fine Structure

    Science.gov (United States)

    Xu, Gu; Li, Guifang; LI, Xianya; Liang, Yi; Feng, Zhechuan

    2017-01-01

    Extended X-ray Absorption Fine Structure (EXAFS) has been one of the few structural probes available for crystalline, non-crystalline and even highly disordered specimens. However, the data analysis involves a patchy and tinkering process, including back-and-forth fitting and filtering, leading to ambiguous answers sometimes. Here we try to resolve this long standing problem, to extract the inter-atomic distances from the experimental data by a single step minimization, in order to replace the tedious and tinkering process. The new strategy is built firmly by the mathematical logic, and made straightforward and undeniable. The finding demonstrates that it is possible to break off from the traditional patchy model fitting, and to remove the logical confusion of a priori prediction of the structure to be matched with experimental data, making it a much more powerful technique than the existing methods. The new method is expected to benefit EXAFS users covering all disciplines. Also, it is anticipated that the current work to be the motivation and inspiration to the further efforts. PMID:28181529

  1. Determination of Trace Amounts of Nickel (Ⅱ) by Graphite Furnace Atomic Absorption Spectrometry Coupled with Cloud Point Extraction

    Institute of Scientific and Technical Information of China (English)

    SHAH Syed Mazhar; WANG Hao-nan; SU Xing-guang

    2011-01-01

    A new method based on the cloud point extraction(CPE) for separation and preconcentration of nickel(Ⅱ)and its subsequent determination by graphite furnace atomic absorption spectrometry(GFAAS) was proposed,8-hydroxyquinoline and Triton X-100 were usedl as the ligand and surfactant respectively. Nickel(Ⅱ) can form a hydrophobic complex with 8-hydroxyquinoline, the complex can be extracted into the small volume surfactant rich phase at the cloud point temperature(CPT) for GFAAS determination. The factors affecting the cloud point extraction,such as pH, ligand concentration, surfactant concentration, and the incubation time were optimized. Under the optimal conditions, a detection limit of 12 ng/L and a relative standard deviation(RSD) of 2.9% were obtained for Ni(Ⅱ) determination. The enrichment factor was found to be 25. The proposed method was successfully applied to the determination of nickel(Ⅱ) in certified reference material and different types of water samples and the recovery was in a range of 95% 103%.

  2. Sensitive determination of cadmium in water samples by room temperature ionic liquid-based preconcentration and electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Martinis, Estefania M. [Laboratory of Environmental Research and Services of Mendoza (LISAMEN), (CCT - CONICET - Mendoza), Av. Ruiz Leal S/N Parque General San Martin, C.C. 131, M 5502 IRA Mendoza (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) (Argentina); Olsina, Roberto A. [Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) (Argentina); Departamento de Quimica Analitica, Facultad de Quimica, Bioquimica y Farmacia, Universidad Nacional de San Luis (Argentina); Altamirano, Jorgelina C. [Laboratory of Environmental Research and Services of Mendoza (LISAMEN), (CCT - CONICET - Mendoza), Av. Ruiz Leal S/N Parque General San Martin, C.C. 131, M 5502 IRA Mendoza (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) (Argentina); Instituto de Ciencias Basicas, Universidad Nacional de Cuyo, Mendoza (Argentina); Wuilloud, Rodolfo G. [Laboratory of Environmental Research and Services of Mendoza (LISAMEN), (CCT - CONICET - Mendoza), Av. Ruiz Leal S/N Parque General San Martin, C.C. 131, M 5502 IRA Mendoza (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) (Argentina); Instituto de Ciencias Basicas, Universidad Nacional de Cuyo, Mendoza (Argentina)], E-mail: rwuilloud@mendoza-conicet.gov.ar

    2008-10-17

    A sensitive preconcentration methodology for Cd determination at trace levels in water samples was developed in this work. 1-Butyl-3-methylimidazolium hexafluorophosphate ([C{sub 4}MIM][PF{sub 6}]) room temperature ionic liquid (RTIL) was successfully used for Cd preconcentration, as cadmium-2-(5-bromo-2-pyridylazo)-5-diethylaminophenol complex [Cd-5-Br-PADAP]. Subsequently, Cd was back-extracted from the RTIL phase with 500 {mu}L of 0.5 mol L{sup -1} nitric acid and determined by electrothermal atomic absorption spectrometry (ETAAS). A preconcentration factor of 40 was achieved with 20 mL of sample. The limit of detection (LOD) obtained under optimum conditions was 3 ng L{sup -1} and the relative standard deviation (R.S.D.) for 10 replicates at 1 {mu}g L{sup -1} Cd{sup 2+} concentration level was 3.5%, calculated at peak heights. The calibration graph was linear from concentration levels near the detection limits up to at least 5 {mu}g L{sup -1}. A correlation coefficient of 0.9997 was achieved. Validation of the methodology was performed by standard addition method and analysis of certified reference material (CRM). The method was successfully applied to the determination of Cd in river and tap water samples.

  3. Determination of platinum and palladium in road dust after their separation on immobilized fungus by electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Woinska, Sylwia; Godlewska-Zylkiewicz, Beata, E-mail: bgodlew@uwb.edu.pl

    2011-07-15

    A flow solid phase extraction procedure based on biosorption of Pt(IV) and Pd(II) on Aspergillus sp. immobilized on cellulose resin Cellex-T was proposed for the separation and preconcentration of Pt and Pd before their determination by electrothermal atomic absorption spectrometry (ETAAS). The analytical conditions including sample pH, eluent type, flow rates of sample and eluent solutions were examined. The analytes were selectively retained on the biosorbent in acidic medium (pH 1) and subsequently eluted from the column with 1 mL of thiourea solution (0.25 mol L{sup -1} thiourea in 0.3 mol L{sup -1} HCl). The reproducibility of the procedure was below 5%. The limit of detection of the method was 0.020 ng mL{sup -1} for Pt and 0.012 ng mL{sup -1} for Pd. The method validation was performed by analysis of certified reference materials BCR-723 (tunnel dust) and SARM-76 (platinum ore). The developed separation procedure was applied to the determination of Pt and Pd in road dust samples by ETAAS. The applied biosorbent is characterized by high sorption capacity: 0.47 mg g{sup -1} for Pt and 1.24 mg g{sup -1} for Pd.

  4. Analysis of trace element in intervertebral disc by Atomic Absorption Spectrometry techniques in degenerative disc disease in the Polish population

    Directory of Open Access Journals (Sweden)

    Andrzej Nowakowski

    2015-05-01

    Full Text Available Objective. Although trace elements are regarded crucial and their content has been determined in number of tissue there are only few papers addressing this problem in intervertebral disc in humans. Most of the trace elements are important substrates of enzymes influencing metabolism and senescence process. Others are markers of environmental pollution. Therefore the aim of the research was to analyzed of the trace element content in the intervertebral disc, which may be a vital argument recognizing the background of degenerative changes to be the effect of the environment or metabolic factors. Materials and methods. Material consist of 18 intervertebral disc from 15 patients, acquired in surgical procedure of due to the degenerative disease with Atomic Absorption Spectrometry content of Al, Cd, Co, Pb, Cu, Ni, Mo, Mg, Zn was evaluated. Results. Only 4 of the trace elements were detected in all samples. The correlation analysis showed significant positive age correlation with Al and negative in case of Co. Among elements significant positive correlation was observed between Al/Pb, Co/Mo, Al/Mg, Al/Zn Pb/Zn and Mg/Zn. Negative correlation was observed in Al/Co, Cd/Mg, Co/Mg, Mo/Mg, Co/Zn and Mo/Zn. Conclusions. This study is the first to our knowledge that profiles the elements in intervertebral disc in patients with degenerative changes. We have confirmed significant differences between the trace element contents in intervertebral disc and other tissue. It can be ground for further investigation.

  5. Localized holes and delocalized electrons in photoexcited inorganic perovskites: Watching each atomic actor by picosecond X-ray absorption spectroscopy

    Science.gov (United States)

    Santomauro, Fabio G.; Grilj, Jakob; Mewes, Lars; Nedelcu, Georgian; Yakunin, Sergii; Rossi, Thomas; Capano, Gloria; Al Haddad, André; Budarz, James; Kinschel, Dominik; Ferreira, Dario S.; Rossi, Giacomo; Gutierrez Tovar, Mario; Grolimund, Daniel; Samson, Valerie; Nachtegaal, Maarten; Smolentsev, Grigory; Kovalenko, Maksym V.; Chergui, Majed

    2016-01-01

    We report on an element-selective study of the fate of charge carriers in photoexcited inorganic CsPbBr3 and CsPb(ClBr)3 perovskite nanocrystals in toluene solutions using time-resolved X-ray absorption spectroscopy with 80 ps time resolution. Probing the Br K-edge, the Pb L3-edge, and the Cs L2-edge, we find that holes in the valence band are localized at Br atoms, forming small polarons, while electrons appear as delocalized in the conduction band. No signature of either electronic or structural changes is observed at the Cs L2-edge. The results at the Br and Pb edges suggest the existence of a weakly localized exciton, while the absence of signatures at the Cs edge indicates that the Cs+ cation plays no role in the charge transport, at least beyond 80 ps. This first, time-resolved element-specific study of perovskites helps understand the rather modest charge carrier mobilities in these materials. PMID:28083541

  6. The use of a sequential extraction procedure for heavy metal analysis of house dusts by atomic absorption spectrometry.

    Science.gov (United States)

    Altundag, Huseyin; Dundar, Mustafa Sahin; Doganci, Secil; Celik, Muhammed; Tuzen, Mustafa

    2013-01-01

    In general, dust is considered as house or street dust. Indoor dust, as a contamination source, has been studied for many years. In this work, the original Community Bureau of Reference of the European Commission (BCR) three-stage sequential extraction procedure was applied to the fractionation of Cr, Cu, Fe, Mn, Pb, and Zn in 20 house dust samples from five different areas of Sakarya, Turkey. Acetic acid, hydroxylammonium chloride, and hydrogen peroxide plus ammonium acetate were used for the first, second, and third steps of the BCR method, respectively. The extracts were analyzed for the studied heavy metals using flame atomic absorption spectrometry. Validation of the results was performed by using a standard reference material (BCR 701 Sediment) to certify the experimental results obtained and to evaluate the reliability of the method used. The elemental loadings typically increased in magnitude according to the area order: Izmit Caddesi>Ankara Caddesi >Erenler>Karaman>Korucuk. The results were in agreement with values reported in the literature.

  7. Determination of platinum and palladium in road dust after their separation on immobilized fungus by electrothermal atomic absorption spectrometry

    Science.gov (United States)

    Woińska, Sylwia; Godlewska-Żyłkiewicz, Beata

    2011-07-01

    A flow solid phase extraction procedure based on biosorption of Pt(IV) and Pd(II) on Aspergillus sp. immobilized on cellulose resin Cellex-T was proposed for the separation and preconcentration of Pt and Pd before their determination by electrothermal atomic absorption spectrometry (ETAAS). The analytical conditions including sample pH, eluent type, flow rates of sample and eluent solutions were examined. The analytes were selectively retained on the biosorbent in acidic medium (pH 1) and subsequently eluted from the column with 1 mL of thiourea solution (0.25 mol L - 1 thiourea in 0.3 mol L - 1 HCl). The reproducibility of the procedure was below 5%. The limit of detection of the method was 0.020 ng mL - 1 for Pt and 0.012 ng mL - 1 for Pd. The method validation was performed by analysis of certified reference materials BCR-723 (tunnel dust) and SARM-76 (platinum ore). The developed separation procedure was applied to the determination of Pt and Pd in road dust samples by ETAAS. The applied biosorbent is characterized by high sorption capacity: 0.47 mg g - 1 for Pt and 1.24 mg g - 1 for Pd.

  8. Standard test method for graphite furnace atomic absorption spectrometric determination of lead and cadmium extracted from ceramic foodware

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2000-01-01

    1.1 This test method covers procedures for using graphite furnace atomic absorption spectroscopy (GFAAS) to quantitatively determine lead and cadmium extracted by acetic acid at room temperature from the food-contact surface of foodware. The method is applicable to food-contact surfaces composed of silicate-based materials (earthenware, glazed ceramicware, decorated ceramicware, decorated glass, and lead crystal glass) and is capable of determining lead concentrations greater than 0.005 to 0.020 g/mL and cadmium concentrations greater than 0.0005 to 0.002 g/mL, depending on instrument design. 1.2 This test method also describes quality control procedures to check for contamination and matrix interference during GFAAS analyses and a specific sequence of analytical measurements that demonstrates proper instrument operation during the time period in which sample solutions are analyzed. 1.3 Cleaning and other contamination control procedures are described in this test method. Users may modify contamination cont...

  9. Determination of molybdenum in plants by vortex-assisted emulsification solidified floating organic drop microextraction and flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Oviedo, Jenny A.; Fialho, Lucimar L.; Nóbrega, Joaquim A., E-mail: djan@terra.com.br

    2013-08-01

    A fast and sensitive procedure for extraction and preconcentration of molybdenum in plant samples based on solidified floating organic drop microextraction combined with flame atomic absorption spectrometry and discrete nebulization was developed. 8-Hydroxyquinoline (8-HQ) was used as complexing agent. The experimental conditions established were: 0.5% m v{sup −1} of 8-HQ, 60 μL of 1-undecanol as the extractant phase, 2 min vortex extraction time, centrifugation for 2 min at 2000 rpm, 10 min into an ice bath and discrete nebulization by introducing 200 μL of solution. The calibration curve was linear from 0.02 to 4.0 mg L{sup −1} with a limit of detection of 4.9 μg L{sup −1} and an enhancement factor of 67. The relative standard deviations for ten replicate measurements of 0.05 and 1.0 mg L{sup −1} Mo were 6.0 and 14.5%, respectively. The developed procedure was applied for determining molybdenum in corn samples and accuracy was proved using certified reference materials. - Highlights: ► Molybdenum was determined in plants by flame AAS. ► Flame AAS sensitivity was improved using microextraction and discrete nebulization. ► The developed procedure can be easily implemented in routine analysis. ► Green chemistry principles are followed.

  10. Sequential injection ionic liquid dispersive liquid-liquid microextraction for thallium preconcentration and determination with flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Anthemidis, Aristidis N.; Ioannou, Kallirroy-Ioanna G. [Aristotle University, Laboratory of Analytical Chemistry, Department of Chemistry, Thessaloniki (Greece)

    2012-08-15

    A novel, automatic on-line sequential injection dispersive liquid-liquid microextraction (SI-DLLME) method, based on 1-hexyl-3-methylimidazolium hexafluorophosphate ([Hmim][PF{sub 6}]) ionic liquid as an extractant solvent was developed and demonstrated for trace thallium determination by flame atomic absorption spectrometry. The ionic liquid was on-line fully dispersed into the aqueous solution in a continuous flow format while the TlBr{sub 4} {sup -} complex was easily migrated into the fine droplets of the extractant due to the huge contact area of them with the aqueous phase. Furthermore, the extractant was simply retained onto the surface of polyurethane foam packed into a microcolumn. No specific conditions like low temperature are required for extractant isolation. All analytical parameters of the proposed method were investigated and optimized. For 15 mL of sample solution, an enhancement factor of 290, a detection limit of 0.86 {mu}g L{sup -1} and a precision (RSD) of 2.7% at 20.0 {mu}g L{sup -1} Tl(I) concentration level, was obtained. The developed method was evaluated by analyzing certified reference materials while good recoveries from environmental and biological samples proved that present method was competitive in practical applications. (orig.)

  11. Dispersive Liquid-Liquid Microextraction of Bismuth in Various Samples and Determination by Flame Atomic Absorption Spectrometry

    Directory of Open Access Journals (Sweden)

    Teslima Daşbaşı

    2016-01-01

    Full Text Available A dispersive liquid-liquid microextraction method for the determination of bismuth in various samples by flame atomic absorption spectrometry is described. In this method, crystal violet was used as counter positive ion for BiCl4- complex ion, chloroform as extraction solvent, and ethanol as disperser solvent. The analytical parameters that may affect the extraction efficiency like acidity of sample, type and amount of extraction and disperser solvents, amount of ligand, and extraction time were studied in detail. The effect of interfering ions on the analyte recovery was also investigated. The calibration graph was linear in the range of 0.040–1.00 mg L−1 with detection limit of 4.0 μg L−1 (n=13. The precision as relative standard deviation was 3% (n=11, 0.20 mg L−1 and the enrichment factor was 74. The developed method was applied successfully for the determination of bismuth in various water, pharmaceutical, and cosmetic samples and the certified reference material (TMDA-64 lake water.

  12. Non-patchy strategy for inter-atomic distances from Extended X-ray Absorption Fine Structure

    Science.gov (United States)

    Xu, Gu; Li, Guifang; Li, Xianya; Liang, Yi; Feng, Zhechuan

    2017-02-01

    Extended X-ray Absorption Fine Structure (EXAFS) has been one of the few structural probes available for crystalline, non-crystalline and even highly disordered specimens. However, the data analysis involves a patchy and tinkering process, including back-and-forth fitting and filtering, leading to ambiguous answers sometimes. Here we try to resolve this long standing problem, to extract the inter-atomic distances from the experimental data by a single step minimization, in order to replace the tedious and tinkering process. The new strategy is built firmly by the mathematical logic, and made straightforward and undeniable. The finding demonstrates that it is possible to break off from the traditional patchy model fitting, and to remove the logical confusion of a priori prediction of the structure to be matched with experimental data, making it a much more powerful technique than the existing methods. The new method is expected to benefit EXAFS users covering all disciplines. Also, it is anticipated that the current work to be the motivation and inspiration to the further efforts.

  13. Separation and enrichment of gold(III) from environmental samples prior to its flame atomic absorption spectrometric determination

    Energy Technology Data Exchange (ETDEWEB)

    Senturk, Hasan Basri; Gundogdu, Ali [Department of Chemistry, Faculty of Arts and Sciences, Karadeniz Technical University, 61080 Trabzon (Turkey); Bulut, Volkan Numan [Department of Chemistry, Faculty of Arts and Sciences, Karadeniz Technical University, 28049 Giresun (Turkey); Duran, Celal [Department of Chemistry, Faculty of Arts and Sciences, Karadeniz Technical University, 61080 Trabzon (Turkey); Soylak, Mustafa [Department of Chemistry, Faculty of Arts and Sciences, Erciyes University, 38039 Kayseri (Turkey)], E-mail: soylak@erciyes.edu.tr; Elci, Latif [Department of Chemistry, Faculty of Arts and Sciences, Pamukkale University, 20020 Denizli (Turkey); Tufekci, Mehmet [Department of Chemistry, Faculty of Arts and Sciences, Karadeniz Technical University, 61080 Trabzon (Turkey)

    2007-10-22

    A simple and accurate method was developed for separation and enrichment of trace levels of gold in environmental samples. The method is based on the adsorption of Au(III)-diethyldithiocarbamate complex on Amberlite XAD-2000 resin prior to the analysis of gold by flame atomic absorption spectrometry after elution with 1 mol L{sup -1} HNO{sub 3} in acetone. Some parameters including nitric acid concentration, eluent type, matrix ions, sample volume, sample flow rate and adsorption capacity were investigated on the recovery of gold(III). The recovery values for gold(III) and detection limit of gold were greater than 95% and 16.6 {mu}g L{sup -1}, respectively. The preconcentration factor was 200. The relative standard deviation of the method was <6%. The adsorption capacity of the resin was 12.3 mg g{sup -1}. The validation of the presented procedure was checked by the analysis of CRM-SA-C Sandy Soil certified reference material. The presented procedure was applied to the determination of gold in some environmental samples.

  14. A method optimization study for atomic absorption spectrophotometric determination of total zinc in insulin using direct aspiration technique

    Directory of Open Access Journals (Sweden)

    Sadia Ata

    2015-03-01

    Full Text Available A sensitive, reliable and relative fast method has been developed for the determination of total zinc in insulin by atomic absorption spectrophotometer. This designed study was used to optimize the procedures for the existing methods. Spectrograms of both standard and sample solutions of zinc were recorded by measuring the absorbance at 213.9 nm for determination of total zinc. System suitability parameters were evaluated and were found to be within the limits. Linearity was evaluated through graphical representation of concentration versus absorbance. Repeatability (intra-day and intermediate precision (inter-day were assessed by analyzing working standard solutions. Accuracy and robustness were experimented from the standard procedures. The percentage recovery of zinc was found to be 99.8%, relative standard deviation RSD 1.13%, linearity of determination LOD 0.0032 μg/mL, and limit of quantization LOQ 0.0120 μg/mL. This developed and proposed method was then validated in terms of accuracy, precision, linearity and robustness which can be successfully used for the quantization of zinc in insulin.

  15. Graphene for separation and preconcentration of trace amounts of cobalt in water samples prior to flame atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    Yukun Wang

    2016-09-01

    Full Text Available A new sensitive and simple method was developed for the preconcentration of trace amounts of cobalt (Co using 1-(2-pyridylazo-2-naphthol (PAN as chelating reagent prior to its determination by flame atomic absorption spectrometry. The proposed method is based on the utilization of a column packed with graphene as sorbent. Several effective parameters on the extraction and complex formation were selected and optimized. Under optimum conditions, the calibration graph was linear in the concentration range of 5.0–240.0 μg L−1 with a detection limit of 0.36 μg L−1. The relative standard deviation for ten replicate measurements of 20.0 and 100.0 μg L−1 of Co were 3.45 and 3.18%, respectively. Comparative studies showed that graphene is superior to other adsorbents including C18 silica, graphitic carbon, and single- and multi-walled carbon nanotubes for the extraction of Co. The proposed method was successfully applied in the analysis of four real environmental water samples. Good spiked recoveries over the range of 95.8–102.6% were obtained.

  16. Electromagnetically induced absorption due to transfer of coherence and coherence population oscillation for the Fg = 3 →Fe = 4 transition in 85Rb atoms

    Science.gov (United States)

    Rehman, Hafeez Ur; Mohsin, Muhammad Qureshi; Noh, Heung-Ryoul; Kim, Jin-Tae

    2016-12-01

    Lineshapes for the electromagnetically induced absorption (EIA) of thermal 85Rb atoms in a degenerate two-level system have been investigated using matching (σ∥σ , π∥π) and orthogonal (σ ⊥ σ , π ⊥ π) polarization configurations of coupling and probe beams. EIA signals, which result from coherence population oscillation and transfer of coherence of the excited state, are obtained in detail theoretically and experimentally. The observed EIA linewidths, which are limited due to the decoherence rate between the magnetic sublevels in the ground state from transit-time relaxation, match well with the calculated ones. Decompositions of the absorption signals analyzed with respect to magnetic sublevels of the ground state show that enhanced or decreased absorption signals for each component of magnetic sublevels in the ground state depend on several factors. These factors include the decay rates and transition strengths, which determine the overall absorption spectral profile.

  17. Determination of the Extractable Speciation and Total Amount of Zinc and Manganese in Cotton Textiles by Flame Atomic Absorption Spectrometry%火焰原子吸收光谱法测定纯棉纺织品中锌和锰的可提取态与总量

    Institute of Scientific and Technical Information of China (English)

    祖文川; 李冰宁; 汪雨; 武彦文; 陈舜琮

    2013-01-01

    Zinc and manganese in cotton textiles were extracted into the acidic sweat,and the extractable speciation was then determined by flame atomic absorption spectrometry(FAAS). Meanwhile,a method was used to determine the total amount of zinc and manganese in cotton textiles by FAAS assisted by microwave digestion. The detection limits for zinc and manganese were 2. 0 and 3. 0 μg·L-1,respectively. The relative standard deviations for the extractable speciation and total amount determination were in the range of 1. 8%-6. 6 %, and the spiked recoveries were in the range of 91. 2% -104. 8%. Five kinds of cotton textiles purchased from the Beijing market were determined. The extractable speciation amount of zinc and manganese were in the range of 0. 31 -3. 26 μg·g-1 and 0. 19 - 1. 39 μg·g-1 ,and the total amount were in the range of 3. 43-13. 31 μg·g-1 and 0. 56 - 3. 17 μg·g -1,respectively.%采用酸性汗液提取纯棉纺织品中锌和锰,火焰原子吸收光谱法(FAAS)测定可提取态含量;同时建立了微波辅助消解溶样,FAAS测定纯棉纺织品中锌和锰总量的方法.锌和锰的检出限分别为2.0和3.0 μg·L-1,可提取态和总量测定结果的相对标准偏差在1.8%~6.6%之间,加标回收率在91.2%~104.8%范围.对5种北京市市售纯棉纺织品测定,锌的可提取态含量在0.31~3.26 μg·g-1之间,总量为3.43~37.93μg·g-1;锰的可提取态含量在0.19~1.39 μg·g-1之间,总量为0.56~3.17 μg·g-1.

  18. 离子液体[Bmim]PF6萃取-火焰原子吸收法测定水中痕量镉%Determination of Trace Cadmium in Water by Flame Atomic Absorption Spectrometry/with Ionic Liquid Extraction

    Institute of Scientific and Technical Information of China (English)

    王良; 李清; 闫永胜; 崔运成

    2011-01-01

    A novel method for the separation and determination of trace cadmium in environmental water sample by flame atomic absorption spectrometry (FAAS) with ionic liquid extraction was proposed. When the acidity of the solvent was pH 8, ionic liquid 1-butyl-3-methylimi dazolium hexafluorophosphate ([Bmim]PF6) was used as extractant, dithizone as the chelant, the sample was extracted for 3 min and determined by FAAS. The research result indicated that under optimum conditions, there was favorable linearity relation between 0. 15 and 58. 2 μg/L, detection limit (3δ) was 0. 095 ng/L (n=11). The recovery of this method was in the range of 90. 0% -108. 0% . The relative standard deviation is less than 5. 8% for the analysis of practical sample.%1 引言化学工业排放的废水含有大量金属镉,对环境产生严重危害,因而环境水样中痕量镉的准确测定具有重要意义.目前,常用原子吸收光谱法[1]测定痕量的镉,但由于环境水样中镉的含量低且样品复杂,为了提高分析方法的灵敏度和选择性,样品的预分离与富集至关重要.液-液萃取是一种常用的预分离与富集方法,但常用有机溶剂作萃取剂,易带来二次污染.离子液体是一种无毒、无污染、不挥发的"绿色溶剂"[2],具有安全、高效、环保等优点[3],已萃取分离了多种金属离子[4-5].本实验以双硫腙(H2Dz)为螯合剂,以离子液体1-丁基-3-甲基咪唑六氟磷酸盐( [Bmim]PF6)为萃取剂.用火焰原子吸收光谱法(FAAS)测定了离子液体相中的Cd,建立了痕量Cd的分离与分析方法,并应用于环境水样的分析.

  19. DETERMINATION OF HEAVY METAL SPECIES IN THE MUNICIPAL SEWAGE SLUDGE OF GUANGZHOU BY MICROWAVE DIGESTION- FLAM ATOMIC ADSORPTION SPECTROMETRY (FAAS)%微波消解-火焰原子吸收法测定广州市污水污泥中重金属的活性形态

    Institute of Scientific and Technical Information of China (English)

    刘敬勇; 孙水裕

    2011-01-01

    Flame atomic adsorption spectrometry was used to determine the total content and fractions of Gu, Zn,Ph, Ct, Ni, Mn in the sewage sludge from four different Wastewater Treatment Plants, Guangzhou. The airdried samples were dissolved in HNO3-HF before the total content determination, or, sequentially extracted with Community Bureau of Reference (BCR) three-step method before species determination for the heavy metals.The results showed that the contents of heavy metals in the sewage sludge were lower than that of the average values in China. The contents of Cu, Zn, Mn, Ni were relatively with large variation, but Pb, Cr was much lower. Although the contents of heavy metals were higher than the background values of Pearl River Delta crop soil, except for Cu content in one sludge sample, the others met the Standards of Pollutants Control in sludge for agricultural uses (GB18918-2002). Heavy metal contents in selected sludges had different forms. In the industrial sewage sludge, Cu, Cr existed mainly in oxidisable forms, but Pb was in the state of reducible and residual fractions. In the domestic sewage sludge, the heavy metals exist mainly in oxidisable and residual fractions, but the percentage of Mn in the exchangeable fraction and Zn in the oxidizable fraction was high. In all, the portion of mobile Cu, Zn and Mn species was high in the four sewage sludges examined, suggesting potential risk for transformation.%以广州4个大型污水处理厂的压滤出厂污泥为实验材料,采用BCR三步浸提法对污泥中Cu、Zn、Pb、Cr、Ni、Mn的4种形态进行测定,以HNO3-HF进行微波全量消解,利用火焰原子吸收(FAAS)检测Cu、Zn、Pb、Cr、Ni、Mn的全量和各形态的含量.结果表明,广州4种不同城市污泥中重金属含量低于全国污泥均值,其中Cu、Zn、Mn、Ni含量较高,变化幅度较大,而Pb、Cr含量较低.除1种污泥中Cu超标外,其它重金属基本符合国家农用控制标准(GB18918-2002),但所有污泥中

  20. On the opportunity of spectroscopic determination of absolute atomic densities in non-equilibrium plasmas from measured relative intensities within resonance multiplets distorted by self-absorption

    CERN Document Server

    Lavrov, B P

    2007-01-01

    The opportunities of the application of the recently proposed approach in optical emission spectroscopy of non-equilibrium plasmas have been studied. The approach consists of several methods of the determination of {\\em absolute} particle densities of atoms from measured {\\em relative} intensities within resonance multiplets distorted by self-absorption. All available spectroscopic data concerning resonance spectral lines of atoms having multiplet ground states from boron up to gallium were analyzed. It is found that in the case of C, O, F, S and Cl atoms an application of the methods needs VUV technique, while densities of B, Al, Si, Sc, Ti, V, Co, Ni, Ga atoms may be obtained by means of the intensity measurements in UV and visible parts of emission spectra suitable for ordinary spectrometers used for optical diagnostics and monitoring of non-equilibrium plasmas including industrial plasma technologies.

  1. Electromagnetically induced absorption and transparency in degenerate two level systems of metastable Kr atoms and measurement of Landé g-factor

    Science.gov (United States)

    Kale, Y. B.; Tiwari, V. B.; Mishra, S. R.; Singh, S.; Rawat, H. S.

    2016-12-01

    We report electromagnetically induced absorption (EIA) and transparency (EIT) resonances of sub-natural linewidth in degenerate two level systems (DTLSs) of metastable 84Kr (84Kr*) and 83Kr (83Kr*) atoms. Using the spectrally narrow EIA signals obtained corresponding to the closed hyperfine transition 4p55s[3/2]2(F=13/2) to 4p55p[5/2]3(F‧ = 15 / 2) in 83Kr* atom, we have measured the Landé g-factor (gF) for the lower hyperfine level involved in this transition by application of small values of magnetic field of few Gauss.

  2. Quantifying uncertainty in the measurement of arsenic in suspended particulate matter by Atomic Absorption Spectrometry with hydride generator

    Directory of Open Access Journals (Sweden)

    Ahuja Tarushee

    2011-04-01

    Full Text Available Abstract Arsenic is the toxic element, which creates several problems in human being specially when inhaled through air. So the accurate and precise measurement of arsenic in suspended particulate matter (SPM is of prime importance as it gives information about the level of toxicity in the environment, and preventive measures could be taken in the effective areas. Quality assurance is equally important in the measurement of arsenic in SPM samples before making any decision. The quality and reliability of the data of such volatile elements depends upon the measurement of uncertainty of each step involved from sampling to analysis. The analytical results quantifying uncertainty gives a measure of the confidence level of the concerned laboratory. So the main objective of this study was to determine arsenic content in SPM samples with uncertainty budget and to find out various potential sources of uncertainty, which affects the results. Keeping these facts, we have selected seven diverse sites of Delhi (National Capital of India for quantification of arsenic content in SPM samples with uncertainty budget following sampling by HVS to analysis by Atomic Absorption Spectrometer-Hydride Generator (AAS-HG. In the measurement of arsenic in SPM samples so many steps are involved from sampling to final result and we have considered various potential sources of uncertainties. The calculation of uncertainty is based on ISO/IEC17025: 2005 document and EURACHEM guideline. It has been found that the final results mostly depend on the uncertainty in measurement mainly due to repeatability, final volume prepared for analysis, weighing balance and sampling by HVS. After the analysis of data of seven diverse sites of Delhi, it has been concluded that during the period from 31st Jan. 2008 to 7th Feb. 2008 the arsenic concentration varies from 1.44 ± 0.25 to 5.58 ± 0.55 ng/m3 with 95% confidence level (k = 2.

  3. Determination of ultra trace arsenic species in water samples by hydride generation atomic absorption spectrometry after cloud point extraction

    Energy Technology Data Exchange (ETDEWEB)

    Ulusoy, Halil Ibrahim, E-mail: hiulusoy@yahoo.com [University of Cumhuriyet, Faculty of Science, Department of Chemistry, TR-58140, Sivas (Turkey); Akcay, Mehmet; Ulusoy, Songuel; Guerkan, Ramazan [University of Cumhuriyet, Faculty of Science, Department of Chemistry, TR-58140, Sivas (Turkey)

    2011-10-10

    Graphical abstract: The possible complex formation mechanism for ultra-trace As determination. Highlights: {yields} CPE/HGAAS system for arsenic determination and speciation in real samples has been applied first time until now. {yields} The proposed method has the lowest detection limit when compared with those of similar CPE studies present in literature. {yields} The linear range of the method is highly wide and suitable for its application to real samples. - Abstract: Cloud point extraction (CPE) methodology has successfully been employed for the preconcentration of ultra-trace arsenic species in aqueous samples prior to hydride generation atomic absorption spectrometry (HGAAS). As(III) has formed an ion-pairing complex with Pyronine B in presence of sodium dodecyl sulfate (SDS) at pH 10.0 and extracted into the non-ionic surfactant, polyethylene glycol tert-octylphenyl ether (Triton X-114). After phase separation, the surfactant-rich phase was diluted with 2 mL of 1 M HCl and 0.5 mL of 3.0% (w/v) Antifoam A. Under the optimized conditions, a preconcentration factor of 60 and a detection limit of 0.008 {mu}g L{sup -1} with a correlation coefficient of 0.9918 was obtained with a calibration curve in the range of 0.03-4.00 {mu}g L{sup -1}. The proposed preconcentration procedure was successfully applied to the determination of As(III) ions in certified standard water samples (TMDA-53.3 and NIST 1643e, a low level fortified standard for trace elements) and some real samples including natural drinking water and tap water samples.

  4. Liquid chromatography-electrothermal atomic absorption spectrometry for the separation and preconcentration of molybdenum in milk and infant formulas.

    Science.gov (United States)

    López-García, I; Viñas, P; Romero-Romero, R; Hernández-Córdoba, M

    2007-08-06

    Two procedures for the electrothermal atomic absorption spectrometric determination of molybdenum in milk and infant formulas using slurried samples are described. For powdered milk samples, 10% (m/v) slurries were prepared in a medium containing 25 and 75% (v/v) concentrated hydrogen peroxide and hydrofluoric acid, respectively, and introduced directly into the furnace. Palladium (200 microg mL(-1)) was used as the modifier and calibration was carried out using aqueous standards prepared in the same medium. The detection limit was 0.02 microg g(-1) for powdered milk samples suspended at 10% (m/v) (equivalent to 2 microg L(-1)). The relative standard deviation (R.S.D.) for five measurements was 1.9%, the characteristic mass being 25 pg. For liquid milk samples, a procedure was proposed based on preconcentration and removal of the matrix, using ionic exchange (Amberlite IRA 743) and elution of molybdenum with 5% (m/v) NaOH. In this case, a 30-fold improvement in the calibration slope was achieved, leading to a detection limit of 0.04 microg L(-1) for liquid samples diluted to 10%. The R.S.D. was 3.5%. Using a size-based separation procedure, it was found that molybdenum is present in its inorganic form or associated to low molecular weight substances in cow milk, while in breast milk it is associated to proteins. The reliability of the procedure was checked by comparing the results obtained with those found using a previous mineralization stage and by analyzing three certified reference materials, namely, BCR 063R (skim milk powder), NBS 1549 (non-fat milk powder) and NBS 8435 (whole milk powder).

  5. Determination of calcium, magnesium and zinc in lubricating oils by flame atomic absorption spectrometry using a three-component solution.

    Science.gov (United States)

    Zmozinski, Ariane V; de Jesus, Alexandre; Vale, Maria G R; Silva, Márcia M

    2010-12-15

    Lubricating oils are used to decrease wear and friction of movable parts of engines and turbines, being in that way essential for the performance and the increase of that equipment lifespan. The presence of some metals shows the addition of specific additives such as detergents, dispersals and antioxidants that improve the performance of these lubricants. In this work, a method for determination of calcium, magnesium and zinc in lubricating oil by flame atomic absorption spectrometry (F AAS) was developed. The samples were diluted with a small quantity of aviation kerosene (AVK), n-propanol and water to form a three-component solution before its introduction in the F AAS. Aqueous inorganic standards diluted in the same way have been used for calibration. To assess the accuracy of the new method, it was compared with ABNT NBR 14066 standard method, which consists in diluting the sample with AVK and in quantification by F AAS. Two other validating methods have also been used: the acid digestion and the certified reference material NIST (SRM 1084a). The proposed method provides the following advantages in relation to the standard method: significant reduction of the use of AVK, higher stability of the analytes in the medium and application of aqueous inorganic standards for calibration. The limits of detection for calcium, magnesium and zinc were 1.3 μg g(-1), 0.052 μg g(-1) and 0.41 μg g(-1), respectively. Concentrations of calcium, magnesium and zinc in six different samples obtained by the developed method did not differ significantly from the results obtained by the reference methods at the 95% confidence level (Student's t-test and ANOVA). Therefore, the proposed method becomes an efficient alternative for determination of metals in lubricating oil.

  6. Comparison of colorimetry and electrothermal atomic absorption spectroscopy for the quantification of non-transferrin bound iron in human sera.

    Science.gov (United States)

    Jittangprasert, Piyada; Wilairat, Prapin; Pootrakul, Pensri

    2004-12-01

    This paper describes a comparison of two analytical techniques, one employing bathophenanthrolinedisulfonate (BPT), a most commonly-used reagent for Fe (II) determination, as chromogen and an electrothermal atomic absorption spectroscopy (ETAAS) for the quantification of non-transferrin bound iron (NTBI) in sera from thalassemic patients. Nitrilotriacetic acid (NTA) was employed as the ligand for binding iron from low molecular weight iron complexes present in the serum but without removing iron from the transferrin protein. After ultrafiltration the Fe (III)-NTA complex was then quantified by both methods. Kinetic study of the rate of the Fe (II)-BPT complex formation for various excess amounts of NTA ligand was also carried out. The kinetic data show that a minimum time duration (> 60 minutes) is necessary for complete complex formation when large excess of NTA is used. Calibration curves given by colorimetric and ETAAS methods were linear over the range of 0.15-20 microM iron (III). The colorimetric and ETAAS methods exhibited detection limit (3sigma) of 0.13 and 0.14 microM, respectively. The NTBI concentrations from 55 thalassemic serum samples measured employing BPT as chromogen were statistically compared with the results determined by ETAAS. No significant disagreement at 95% confidence level was observed. It is, therefore, possible to select any one of these two techniques for determination of NTBI in serum samples of thalassemic patients. However, the colorimetric procedure requires a longer analysis time because of a slow rate of exchange of NTA ligand with BPT, leading to the slow rate of formation of the colored complex.

  7. In-situ measurements of low-level mercury vapor exposure from dental amalgam with zeeman atomic absorption spectroscopy.

    Science.gov (United States)

    Halbach, Stefan; Welzl, Gerhard

    2004-01-01

    Alongside food, emissions from amalgam fillings are an essential contribution to man's mercury burden. Previous methods for the determination of intraoral mercury vapor (Hg degrees ) release used principally some form of preconcentration of Hg on gold (film or wool), allowing relatively few measurements with unknown precision and sensitivity at selected times. Recently available computer-controlled Hg detectors operating on Zeeman atomic absorption spectroscopy (ZAAS) facilitate the direct real-time measurement of Hg degrees concentrations. It was the aim to adapt this method for a comparative investigation of emission processes from fillings in situ and from amalgam specimens in vitro. In addition to the ZAAS instrument, the apparatus consisted of a pump, magnetic valves, an electronic flow controller and a handle with a disposable mouth piece for aspiration of oral air. A programmable timer integrated the computer-controlled instrument operation and the data collection into a standard sampling protocol. A fast exponential decay of the emission was found after stimulation of amalgam specimens and of fillings in situ (halftimes 8.6 and 10.7 min). Precision was evaluated by a series of measurements on a single patient which indicated a consistently low coefficient of variation between 18% and 25%. After insertion of a few new fillings, sensitivity was high enough to detect a significant increase in emission against the background emission from the majority of old fillings. Zeeman-AAS in connection with a semi-automated sampling protocol and data storage provides precise in-situ measurements of Hg degrees emission from dental amalgam with real-time resolution. This facilitates the detailed exploration of the Hg degrees release kinetics and the applicability to large-scale studies.

  8. Direct and combined methods for the determination of chromium, copper, and nickel in honey by electrothermal atomic absorption spectroscopy.

    Science.gov (United States)

    Rodríguez García, J C; Barciela García, J; Herrero Latorre, C; García Martín, S; Peña Crecente, R M

    2005-08-24

    In the present work, direct methods for the determination of chromium, copper, and nickel in honey by electrothermal atomic absorption spectroscopy were developed using experimental design as an optimization tool. Once the optimum conditions for the individual methods were established, a direct method for the combined determination of the three elements was optimized using the response surface tool. Palladium was used as chemical modifier in all cases. Honey was diluted in water, hydrogen peroxide, and nitric acid. Triton X-100 was added to minimize the matrix effect and the viscosity of the sample. The RSD (better than 10%) and the analytical recovery (98-103%) were acceptable for all of the developed methods. Calibration graphs were used in the four methods to determine the concentration of the analytes in the sample. The detection limits of the combined method (0.21, 0.35, and 0.37 microg L(-)(1) for Cr, Cu, and Ni, respectively) were similar to those obtained for the individual methods (LOD = 0.17, 0.21, 0.33 microg L(-)(1) for Cr, Cu, and Ni, respectively). The direct-combined proposed method has been applied to the determination of chromium, copper, and nickel content in representative honey samples from Galicia (northwestern Spain). The concentrations found in the analyzed samples were in the range of (5.75 +/- 0.64)-(26.4 +/- 0.38) ng g(-)(1) of Cr, (79 +/- 7.8)-(2049 +/- 80) ng g(-)(1) of Cu, and (12.6 +/- 1.36)-(172 +/- 6.88) ng g(-)(1) of Ni.

  9. Simple decomposition procedure for determination of selenium in whole blood, serum and urine by hydride generation atomic absorption spectroscopy.

    Science.gov (United States)

    Tiran, B; Tiran, A; Rossipal, E; Lorenz, O

    1993-12-01

    A digestion procedure for selenium determination by hydride generation atomic absorption spectroscopy (AAS) in whole blood, serum and urine is described, it employs sulfuric acid, hydrogen peroxide and vanadium (V) sulfuric acid reagent solution. The method is rapid, uses no explosive reagents and can be performed at a constant temperature of 100 degrees C. Therefore, it is easily applicable in a routine clinical laboratory for a large amount of samples. The coefficient of intra-assay variation was 4.3-5.6%, the coefficient for inter-assay variation was 5-5.9% in the medium and high concentration range, and 5.8-8.6% in the low range. In analyzing several commercial reference materials our results showed good agreement with the target values. Analytical recovery by addition of sodium selenite and seleno-DL-methionine to samples ranged between 97 and 104%. The correlation between the described digestion procedure and the nitric, sulfuric and perchloric acid digestion procedure recommended by the International Union of Pure and Applied Chemistry showed good agreement for whole blood, serum and for urine. We determined selenium in serum (n = 58) and whole blood (n = 50) in a collective of healthy children from 1 to 5 years living in Styria, Austria. The low values in serum (35 +/- 11 micrograms/L) and whole blood (42 +/- 6 micrograms/L) at one year of life increased significantly to 48 +/- 13 mu/L (p = 0.033) and 55 +/- 6 micrograms/L (p = 0.004) at three years of life in serum and whole blood, respectively. The selenium concentration showed no further increase up to five years of age.(ABSTRACT TRUNCATED AT 250 WORDS)

  10. Selective cloud point extraction and graphite furnace atomic absorption spectrometric determination of molybdenum (VI) ion in seawater samples

    Energy Technology Data Exchange (ETDEWEB)

    Filik, Hayati, E-mail: filik@istanbul.edu.tr [Istanbul University, Faculty of Engineering, Department of Chemistry, Avcilar, 34320 Istanbul (Turkey); Cengel, Tayfun; Apak, Resat [Istanbul University, Faculty of Engineering, Department of Chemistry, Avcilar, 34320 Istanbul (Turkey)

    2009-09-30

    A cloud point extraction process using the nonionic surfactant Triton X-114 to extract molybdenum from aqueous solutions was investigated. The method is based on the complexation reaction of Mo(VI) with 1,2,5,8-tetrahydroxyanthracene-9,10-dione (quinalizarine: QA) and micelle-mediated extraction of the complex. The enriched analyte in the surfactant-rich phase was determined by graphite furnace atomic absorption spectrometry (GFAAS). The optimal extraction and reaction conditions (e.g. pH, reagent and surfactant concentrations, temperature, incubation and centrifugation times) were evaluated and optimized. Under the optimized experimental conditions, the limit of detection (LOD) for Mo(VI) was 7.0 ng L{sup -1} with an preconcentration factor of {approx}25 when 10 mL of sample solution was preconcentrated to 0.4 mL. The proposed method (with extraction) showed linear calibration within the range 0.03-0.6 {mu}g L{sup -1}. The relative standard deviation (RSD) was found to be 3.7% (C{sub Mo(VI)} = 0.05 {mu}g L{sup -1}, n = 5) for pure standard solutions, whereas RSD for the recoveries from real samples ranged between 2 and 8% (mean RSD = 3.9%). The method was applied to the determination of Mo(VI) in seawater and tap water samples with a recovery for the spiked samples in the range of 98-103%. The interference effect of some cations and anions was also studied. In the presence of foreign ions, no significant interference was observed. In order to verify the accuracy of the method, a certified reference water sample was analysed and the results obtained were in good agreement with the certified values.

  11. Determination of Cd, Pb and As in sediments of the Sava River by electrothermal atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    SIMONA MURKO

    2010-01-01

    Full Text Available The applicability of nitric acid, palladium nitrate and a mixture of palladium and magnesium nitrate as matrix modifiers were estimated for the accurate and reproducible determination of cadmium (Cd, lead (Pb and arsenic (As in sediments of the Sava River by electrothermal atomic absorption spectrometry, ETAAS. Decomposition of the samples was done in a closed vessel microwave-assisted digestion system using nitric, hydrochloric and hydrofluoric acids, followed by the addition of boric acid to convert the fluorides into soluble complexes. The parameters for the determination of Cd, Pb and As in sediments were optimised for each individual element and for each matrix modifier. In addition, two sediment reference materials were also analysed. In determination of Cd and Pb, nitric acid was found to be the most appropriate matrix modifier. The accurate and reliable determination of Cd and Pb in sediments was possible also in the presence of boric acid. The use of a mixture of palladium and magnesium nitrate efficiently compensated for matrix effects and enabled the accurate and reliable determination of As in the sediments. Quantification of Cd and As was performed by calibration using acid matched standard solutions, while the standard addition method was applied for the quantification of Pb. The repeatability of the analytical procedure for the determination of Cd, Pb and As in sediments was ±5 % for Cd, ±4 % for Pb and ±2 % for As. The LOD values of the analytical procedure were found to be 0.05 mg/kg for Cd and 0.25 mg/kg for Pb and As, while the LOQ values were 0.16 mg/kg for Cd and 0.83 mg/kg for Pb and As. Finally, Cd, Pb and As were successfully determined in sediments of the Sava River in Slovenia.

  12. Evidence for aluminum-binding erythropoietin by size-exclusion chromatography coupled to electrothermal absorption atomic spectrometry.

    Science.gov (United States)

    Veiga, Marlei; Bohrer, Denise; Noremberg, Simone; do Nascimento, Paulo C; de Carvalho, Leandro M

    2011-11-01

    Erythropoietin (EPO) is a glycoprotein that stimulates erythropoiesis and is clinically used for treating anemia during chronic renal failure and for anemia in preterm infants. EPO formulations usually have elevated rates of contamination due to aluminum (Al), which is toxic to both types of patients. Size-exclusion chromatography (SEC) coupled with graphite furnace atomic absorption spectrometry (GF AAS) was employed to separate proteins and to quantify the amount of aluminum present in the elution volume corresponding to EPO and, therefore, to evaluate possible binding. Because EPO formulations contain human serum albumin (HSA), a chromatographic method was optimized for the separation of these proteins. Subsequent to the chromatographic separation, 1-mL fractions of the column effluent were collected, and the Al content in these aliquots was measured by GF AAS. EPO and HSA samples were incubated with Al for 4h at 4°C and 37°C as well as for 16 h at 4°C and 37°C. Afterwards, they were injected into the chromatographic system. These samples were also submitted to ultrafiltration (10 and 50 kDa membranes), and Al was measured in the ultrafiltrates. The results showed that Al was present in the eluent volume corresponding to the EPO peak but not in the HSA peak in the chromatograms. Temperature strengthened the interaction because the Al present in the EPO fraction was 3 times higher at 37°C compared to 4°C. Thirty-eight percent of the Al present in a 2.4 μg/mL EPO standard solution, and approximately 50% of the Al in formulation samples containing approximately 11 μg/mL EPO and either citrate or phosphate, were non-ultrafiltrable, which suggests that EPO is an effective Al acceptor in vitro.

  13. Preconcentration of gold ions from water samples by modified organo-nanoclay sorbent prior to flame atomic absorption spectrometry determination

    Energy Technology Data Exchange (ETDEWEB)

    Afzali, Daryoush, E-mail: daryoush_afzali@yahoo.com [Nanochemistry Department, Research Institute of Environmental Sciences, International Center for Science, High Technology and Environmental Sciences, Kerman (Iran, Islamic Republic of); Mostafavi, Ali [Chemistry Department, Shahid Bahonar University of Kerman, Kerman (Iran, Islamic Republic of); Mirzaei, Mohammad [Nanochemistry Department, Research Institute of Environmental Sciences, International Center for Science, High Technology and Environmental Sciences, Kerman (Iran, Islamic Republic of); Chemistry Department, Shahid Bahonar University of Kerman, Kerman (Iran, Islamic Republic of)

    2010-09-15

    In this work, the applicability of modified organo nanoclay as a new and easy prepared solid sorbent for the preconcentration of trace amounts of Au(III) ion from water samples is studied. The organo nanoclay was modified with 5-(4'-dimethylamino benzyliden)-rhodanine and used as a sorbent for separation of Au(III) ions. The sorption of gold ions was quantitative in the pH range of 2.0-6.0. Quantitative desorption occurred with 6.0 mL of 1.0 mol L{sup -1} Na{sub 2}S{sub 2}O{sub 3}. The amount of eluted Au(III) was measured using flame atomic absorption spectrometry. In the initial solution the linear dynamic range was in the range of 0.45 ng mL{sup -1} to 10.0 {mu}g mL{sup -1}, the detection limit was 0.1 ng mL{sup -1} and the preconcentration factor was 105. Also, the relative standard deviation was {+-}2.3% (n = 8 and C = 2.0 {mu}g mL{sup -1}) and the maximum capacity of the sorbent was 3.9 mg of Au(III) per gram of modified organo nanoclay. The influences of the experimental parameters including sample pH, eluent volume and eluent type, sample volume, and interference of some ions on the recoveries of the gold ion were investigated. The proposed method was applied for preconcentration and determination of gold in different samples.

  14. Species selective preconcentration and quantification of gold nanoparticles using cloud point extraction and electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Hartmann, Georg, E-mail: georg.hartmann@tum.de [Department of Chemistry, Technische Universitaet Muenchen, 85748 Garching (Germany); Schuster, Michael, E-mail: michael.schuster@tum.de [Department of Chemistry, Technische Universitaet Muenchen, 85748 Garching (Germany)

    2013-01-25

    Highlights: Black-Right-Pointing-Pointer We optimized cloud point extraction and ET-AAS parameters for Au-NPs measurement. Black-Right-Pointing-Pointer A selective ligand (sodium thiosulphate) is introduced for species separation. Black-Right-Pointing-Pointer A limit of detection of 5 ng Au-NP per L is achieved for aqueous samples. Black-Right-Pointing-Pointer Measurement of samples with high natural organic mater content is possible. Black-Right-Pointing-Pointer Real water samples including wastewater treatment plant effluent were analyzed. - Abstract: The determination of metallic nanoparticles in environmental samples requires sample pretreatment that ideally combines pre-concentration and species selectivity. With cloud point extraction (CPE) using the surfactant Triton X-114 we present a simple and cost effective separation technique that meets both criteria. Effective separation of ionic gold species and Au nanoparticles (Au-NPs) is achieved by using sodium thiosulphate as a complexing agent. The extraction efficiency for Au-NP ranged from 1.01 {+-} 0.06 (particle size 2 nm) to 0.52 {+-} 0.16 (particle size 150 nm). An enrichment factor of 80 and a low limit of detection of 5 ng L{sup -1} is achieved using electrothermal atomic absorption spectrometry (ET-AAS) for quantification. TEM measurements showed that the particle size is not affected by the CPE process. Natural organic matter (NOM) is tolerated up to a concentration of 10 mg L{sup -1}. The precision of the method expressed as the standard deviation of 12 replicates at an Au-NP concentration of 100 ng L{sup -1} is 9.5%. A relation between particle concentration and the extraction efficiency was not observed. Spiking experiments showed a recovery higher than 91% for environmental water samples.

  15. The determination of low lead levels in the bone of lead-depleted mice by graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Iavicoli, I.; Carelli, G.; Castellino, N. [Univ. Cattolica del Sacro Cuore, Roma (Italy). Inst. of Occupational Health; Schlemmer, G. [Bodenseewerk Perkin-Elmer und Co. GmbH, Ueberlingen (Germany)

    2001-08-01

    Low lead levels in the femurs of mice fed with a lead-depleted diet have been determined by use of electrothermal atomic absorption spectrometry with Zeeman-effect background correction. The method is based on the use of Mg(NO{sub 3}){sub 2}/Pd as matrix modifier which enables significant reduction of the spectral interferences prevalent if chemical modifiers based on NH{sub 4}H{sub 2}PO{sub 4} with either Ca or Mg are used for samples rich in Ca{sub 3}(PO{sub 4}){sub 2} matrix. The method was developed and validated by use of the NIST standard reference material 1486 bone