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Sample records for atomic absorption method

  1. A method optimization study for atomic absorption ...

    African Journals Online (AJOL)

    Sadia Ata

    2014-04-24

    Apr 24, 2014 ... spectrophotometric determination of total zinc in insulin using .... A linear regression by the least squares method is then applied. The value of the determination coefficient (R2 =0.99842) showed excellent linearity of the calibration curve for the ... method is applied repeatedly to multiple sampling of homol-.

  2. Atomic absorption method for the determination of lead in air

    Energy Technology Data Exchange (ETDEWEB)

    Szivos, K.; Polos, L.; Feher, I.; Pungor, E.

    1974-01-01

    An atomic absorption method for the determination of lead in air was used to analyze air quality at a busy area of Budapest. The air was sampled by a personal sampler carried by persons on street duty at one of the busiest spots in Budapest. The air sample was pumped through a membrane filter type Synpor-3. The filter was destroyed in th 3:2 mixture of strong nitric acid/hydrogen peroxide, the acid was distilled, and the residue was then dried and filled to 2 ml with an 0.5% tartaric acid solution. The results were evaluated by means of calibration curves. The method gave a standard deviation of 3 to 5% in 1 to 3 micrograms/ml concentration. In 0.5% tartaric acid solution, the sensitivity was 0.65 micrograms lead/ml 1% absorption. The presence of tartarate increased the sensitivity of the determination by 10 to 13%. A historgram was constructed of the lead contamination in air at one of the busiest spots of Budapest in 1971. The lead content of air was lower in the summer, probably due to the more intense air currents. The samples contained 0.6 to 13 micrograms of lead, depending on the amount and on the pollution of the air driven through the sampler.

  3. Determination of urinary manganese by the direct chelation-extraction method and flameless atomic absorption spectrophotometry.

    Science.gov (United States)

    Watanabe, T; Tokunaga, R; Iwahana, T; Tati, M; Ikeda, M

    1978-01-01

    The direct chelation-extraction method, originally developed by Hessel (1968) for blood lead analysis, has been successfully applied to urinalysis for manganese. The analyses of 35 urine samples containing up to 100 microgram/1 of manganese from manganese-exposed workers showed that the data obtained by this method agree well with those by wet digestion-flame atomic absorption spectrophotometry and also by flameless atomic absorption spectrophotometry. PMID:629893

  4. 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.

  5. Zeeman atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Hadeishi, T.; McLaughlin, R.

    1978-08-01

    The design and development of a Zeeman atomic absorption spectrometer for trace element analysis are described. An instruction manual is included which details the operation, adjustment, and maintenance. Specifications and circuit diagrams are given. (WHK)

  6. 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…

  7. 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...

  8. 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%.

  9. Uranium isotopes quantitatively determined by modified method of atomic absorption spectrophotometry

    Science.gov (United States)

    Lee, G. H.

    1967-01-01

    Hollow-cathode discharge tubes determine the quantities of uranium isotopes in a sample by using atomic absorption spectrophotometry. Dissociation of the uranium atoms allows a large number of ground state atoms to be produced, absorbing the incident radiation that is different for the two major isotopes.

  10. Atomic absorption spectroscopic, conductometric and colorimetric methods for determination of some fluoroquinolone antibacterials using ammonium reineckate

    Science.gov (United States)

    Al-Ghannam, Sheikha M.

    2008-04-01

    Three accurate, rapid and simple atomic absorption spectrometric (AAS), conductometric and colorimetric methods were developed for the determination of gatifloxacin (GTF), moxifloxacin (MXF) and sparfloxacin (SPF). The proposed methods depend upon the reaction of ammonium reineckate with the studied drugs to form stable precipitate of ion-pair complexes, which was dissolved in acetone. The pink coloured complexes were determined either by AAS or colorimetrically at λmax 525 nm directly using the dissolved complex. Using conductometric titration, the studied drugs could be evaluated in 50% (v/v) acetone. The optimizations of various experimental conditions were described. Optimum concentration ranges for the determination of GTF, MXF and SPF were 5.0-150, 40-440 μg mL -1 and 0.10-1.5 mg mL -1 using atomic absorption (AAS), conductometric and colorimetric methods, respectively. Detection and quantification limits are ranges from 1.5 to 2.3 μg mL -1 using AAS method or 30-45 μg mL -1 using colorimetric method. The proposed procedures have been applied successfully to the analysis of these drugs in pharmaceutical formulations and the results are favourably comparable to the reference methods.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. Graphite furnace atomic absorption spectrophotometry--a novel method to quantify blood volume in experimental models of intracerebral hemorrhage.

    Science.gov (United States)

    Kashefiolasl, Sepide; Foerch, Christian; Pfeilschifter, Waltraud

    2013-02-15

    Intracerebral hemorrhage (ICH) accounts for 10% of all strokes and has a significantly higher mortality than cerebral ischemia. For decades, ICH has been neglected by experimental stroke researchers. Recently, however, clinical trials on acute blood pressure lowering or hyperacute supplementation of coagulation factors in ICH have spurred an interest to also design and improve translational animal models of spontaneous and anticoagulant-associated ICH. Hematoma volume is a substantial outcome parameter of most experimental ICH studies. We present graphite furnace atomic absorption spectrophotometric analysis (AAS) as a suitable method to precisely quantify hematoma volumes in rodent models of ICH. Copyright © 2012 Elsevier B.V. All rights reserved.

  1. [Study on lead absorption in pumpkin by atomic absorption spectrophotometry].

    Science.gov (United States)

    Li, Zhen-Xia; Sun, Yong-Dong; Chen, Bi-Hua; Li, Xin-Zheng

    2008-07-01

    A study was carried out on the characteristic of lead absorption in pumpkin via atomic absorption spectrophotometer. The results showed that lead absorption amount in pumpkin increased with time, but the absorption rate decreased with time; And the lead absorption amount reached the peak in pH 7. Lead and cadmium have similar characteristic of absorption in pumpkin.

  2. 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.

  3. 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%.

  4. Determination of total arsenic in fish by hydride-generation atomic absorption spectrometry: method validation, traceability and uncertainty evaluation

    Science.gov (United States)

    Nugraha, W. C.; Elishian, C.; Ketrin, R.

    2017-03-01

    Fish containing arsenic compound is one of the important indicators of arsenic contamination in water monitoring. The high level of arsenic in fish is due to absorption through food chain and accumulated in their habitat. Hydride generation (HG) coupled with atomic absorption spectrometric (AAS) detection is one of the most popular techniques employed for arsenic determination in a variety of matrices including fish. This study aimed to develop a method for the determination of total arsenic in fish by HG-AAS. The method for sample preparation from American of Analytical Chemistry (AOAC) Method 999.10-2005 was adopted for acid digestion using microwave digestion system and AOAC Method 986.15 - 2005 for dry ashing. The method was developed and validated using Certified Reference Material DORM 3 Fish Protein for trace metals for ensuring the accuracy and the traceability of the results. The sources of uncertainty of the method were also evaluated. By using the method, it was found that the total arsenic concentration in the fish was 45.6 ± 1.22 mg.Kg-1 with a coverage factor of equal to 2 at 95% of confidence level. Evaluation of uncertainty was highly influenced by the calibration curve. This result was also traceable to International Standard System through analysis of Certified Reference Material DORM 3 with 97.5% of recovery. In summary, it showed that method of preparation and HG-AAS technique for total arsenic determination in fish were valid and reliable.

  5. Determination of Copper by Graphite Furnace Atomic Absorption Spectrophotometry: A Student Exercise in Instrumental Methods of Analysis.

    Science.gov (United States)

    Williamson, Mark A.

    1989-01-01

    Discusses a student exercise which requires the optimizing of the charring and atomization temperatures by producing a plot of absorbance versus temperature for each temperature parameter. Notes that although the graphite furnace atomic absorption spectroscopy technique has widespread industrial use, there are no published, structured experiments…

  6. Rapid quantitative analysis of magnesium stearate in pharmaceutical powders and solid dosage forms by atomic absorption: method development and application in product manufacturing.

    Science.gov (United States)

    Sugisawa, Keiichi; Kaneko, Takashi; Sago, Tsuyoshi; Sato, Tomonobu

    2009-04-05

    The distribution of magnesium stearate (MgSt) in tablet granule has a significant impact on the compression process. A rapid quantitative method for evaluating magnesium stearate content by atomic absorption was established. The MgSt was extracted from the granule in 0.1 mol/L nitric acid and the resulting free magnesium ion quantitated by atomic absorption. The total analysis time was significantly shortened in comparison to the previously used sample ignition method. This newly established method was evaluated with several drug products and several types of blender. The analytical method was also applied to tablets with poor compression (rough tablet surface). The MgSt content in these rough surface tablets was significantly lower than in tablets with smooth surfaces from the same batch. From these results, this atomic absorption method is considered to be an accurate and useful method for evaluating MgSt distribution and can be applied to tablet manufacturing process validation.

  7. 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.

  8. [Study on cadmium absorption in pumpkin by atomic absorption spectrophotometry].

    Science.gov (United States)

    Li, Zhen-Xia; Jing, Rui-Jun; Dong, Wei-Hua; Li, Xin-Zheng; Liu, Hong

    2006-08-01

    A study was carried out on the characteristic of cadmium absorption in pumpkin by atomic absorption spectrophotometer. The results show that the cadmium absorption amount in pumpkin increased with the increase in cadmium concentration. Meanwhile the cadmium absorption amount in pumpkin increased with time. Eight hours after being cultured in the liquid, the cadmium absorption amount became saturated. The cadmium absorption rate reached the peak after 2 hours, then the absorption rate gradually reduced. The cadmium absorption amount in pumpkin is less in acid or alkali compared with neutral condition. And the absorption amount became minimum in pH 3, while maximum in pH 7.

  9. 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.

  10. 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.

  11. 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...

  12. 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.

  13. Atomic absorption spectroscopic, conductometric and colorimetric methods for determination of fluoroquinolone antibiotics using ammonium reineckate ion-pair complex formation

    Science.gov (United States)

    Ragab, Gamal H.; Amin, Alaa S.

    2004-03-01

    Three accurate, rapid and simple atomic absorption spectrometric, conductometric and colorimetric methods were developed for the determination of norfloxacin (NRF), ciprofloxacin (CIP), ofloxacin (OFL) and enrofloxacin (ENF). The proposed methods depend upon the reaction of ammonium reineckate with the studied drugs to form stable precipitate of ion-pair complexes, which was dissolved in acetone. The pink coloured complexes were determined either by AAS or colorimetrically at λmax 525 nm directly using the dissolved complex. Using conductometric titration, the studied drugs could be evaluated in 50% (v/v) acetone in the range 5.0-65, 4.0-48, 5.0-56 and 6.0-72 μg ml -1 of NRF, CPF, OFL and ENF, respectively. The optimizations of various experimental conditions were described. The results obtained showed good recoveries of 99.15±1.15, 99.30±1.40, 99.60±1.50, and 99.00±1.25% with relative standard deviations of 0.81, 1.06, 0.97, and 0.69% for NRF, CPF, OFL, and ENF, respectively. Applications of the proposed methods to representative pharmaceutical formulations are successfully presented.

  14. 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.

  15. A rapid digestion method for analysis of nickel compounds in tissue by electrothermal atomic absorption spectrometry.

    Science.gov (United States)

    Benson, J M; Eidson, A F; Hanson, R L; Henderson, R F; Hobbs, C H

    1989-08-01

    Quantification of nickel in animal soft tissue is of toxicological interest. A digestion method applying the use of microwave ovens for irradiating samples in Teflon digesters was developed. An acid mixture containing nitric acid (16 M, 1.0 ml g-1 tissue), hydrochloric acid (6 M, 0.5 ml g-1 tissue) and H2O2 (30%, 1.0 ml g-1 tissue) and irradiation at 600 W for 5 min were required for complete dissolution of tissue matrices and nickel compounds. Analyses of Ni in National Bureau of Standards Reference Material 1566 oyster tissue gave 0.87 +/- 0.24 micrograms g 1(mean +/- SD, n = 5), which was in agreement with the NBS certified value of 1.03 +/- 0.19 micrograms g-1. Recoveries of 1-300 micrograms Ni added as nickel sulfate (highly soluble), nickel subsulfide (moderately soluble in biological fluids and acid) or nickel oxide (green high-temperature oxide, low solubility in biological fluids and acid) to lung, liver, lymph node and kidney were quantitative, except in the case of nickel sulfate added to kidney, where recovery was less than quantitative for 1-10 micrograms Ni. The method appears effective for digestion of a variety of tissues requiring Ni analyses.

  16. 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%.

  17. Atomic-absorption determination of copper and zinc in ferroboron

    Energy Technology Data Exchange (ETDEWEB)

    Malinina, R.D.; Toropova, L.S.

    1986-03-01

    This paper reports on the development of an atomic-absorption method for determining copper and zinc impurities in ferroboron, used for alloying steels and special alloys. The work was done on a Model 503 Perkin-Elmer atomic absorption spectrophotometer. Effects of perchloric acid and alloy macrocomponents on zinc and copper atomization were studied. Results by atomic absorption spectrometry were compared with those found by polarography, using a PPT-6016 ac polarograph. Compared with the GOST 14021.7-78 method for determining copper, the proposed procedure is more rapid and decreases the detection limit from 1 X 10/sup -2/ to 5 X 10/sup -3/ wt. %.

  18. 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.

  19. 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.

  20. 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.

  1. Comparison of different sample preparation methods for platinum determination in cultured cells by graphite furnace atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    Man Xiao

    2017-01-01

    Full Text Available Background Platinum-based agents are widely used in chemotherapy against solid tumors and insufficient intracellular drug accumulation is one of the leading causes of platinum resistance which is associated with poor survival of tumor patients. Thus, the detection of intracellular platinum is pivotal for studies aiming to overcome platinum resistance. In the present study, we aimed to establish a reliable graphite furnace atomic absorption spectrometry (GFAAS-based assay to quantify the intracellular platinum content for cultured cells. Methods Several most commonly applied cell preparation methods, including 0.2% HNO3, 0.2% Triton X-100, concentrated nitric acid, RIPA combined with concentrated nitric acid and hydroxide, followed by GFAAS for platinum detection were compared in ovarian, cervical and liver cancer cell lines to obtain the optimal one, and parameters regarding linearity, accuracy, precision and sensitivity were evaluated. Influence of other metals on platinum detection and the storage conditions of samples were also determined. Results The treatment of cells with 0.2% HNO3 was superior to other approaches with fewer platinum loss and better repeatability. The recovery rate and precision of this method were 97.3%–103.0% and 1.4%–3.8%, respectively. The average recoveries in the presence of other metals were 95.1%–103.1%. The detection limit was 13.23 ug/L. The recovery rate of platinum remained acceptable even in cell samples stored in −20 °C or −80 °C for two months. Discussion After comparison, we found that 0.2% HNO3 was optimal for intracellular platinum quantification based on GFAAS, which presented values compatible with that of inductively-coupled plasma mass-spectrometry (ICP-MS, and this is partially attributed to the simplicity of this method. Moreover, the assay was proved to be accurate, sensitive, cost-effective and suitable for the research of platinum-based antitumor therapy.

  2. Trace mercury determination in drinking and natural water after preconcentration and separation by DLLME-SFO method coupled with cold vapor atomic absorption spectrometry

    OpenAIRE

    Abdollahi Atousa; Amirkavehei Mooud; Gheisari Mohammad Mehdi; Tadayon Fariba

    2014-01-01

    A novel dispersive liquid–liquid microextraction based on solidification of floating organic drop (DLLME-SFO) for simultaneous separation/preconcentration of ultra trace amounts of mercury was used. A method based on amalgamation was used for collection of gaseous mercury on gold coated sand (Gold trap). The concentration of mercury was determined by cold vapor atomic absorption spectrometry (CV-AAS). The DLLME-SFO behavior of mercury by using dithizone as complexing agent was systematically ...

  3. 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…

  4. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of chromium in water by graphite furnace atomic absorption spectrophotometry

    Science.gov (United States)

    McLain, B.J.

    1993-01-01

    Graphite furnace atomic absorption spectrophotometry is a sensitive, precise, and accurate method for the determination of chromium in natural water samples. The detection limit for this analytical method is 0.4 microg/L with a working linear limit of 25.0 microg/L. The precision at the detection limit ranges from 20 to 57 percent relative standard deviation (RSD) with an improvement to 4.6 percent RSD for concentrations more than 3 microg/L. Accuracy of this method was determined for a variety of reference standards that was representative of the analytical range. The results were within the established standard deviations. Samples were spiked with known concentrations of chromium with recoveries ranging from 84 to 122 percent. In addition, a comparison of data between graphite furnace atomic absorption spectrophotometry and direct-current plasma atomic emission spectrometry resulted in suitable agreement between the two methods, with an average deviation of +/- 2.0 microg/L throughout the analytical range.

  5. 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.

  6. Determination of lead and cadmium in ceramicware leach solutions by graphite furnace atomic absorption spectroscopy: method development and interlaboratory trial.

    Science.gov (United States)

    Hight, S C

    2001-01-01

    This method was developed to improve sensitivity and eliminate time consuming, evaporative pre-concentration in AOAC Method 973.82 and American Society for Testing and Materials method C738 for testing foodware. The method was developed using leach solutions obtained by leaching 9 differently decorated ceramic vessels with 4% acetic acid for 24 h at room temperature. Lead and cadmium concentrations in leach solutions were 0.005-17,600 and 0.0004-0.500 microg/mL, respectively. Concentrations were determined using peak area, phosphate chemical modifier (8.3 microg PO4(-3)), and a standard curve for quantitation. Optimized pre-atomization and atomization temperatures were 1,300 and 1,800 degrees C, respectively, for Pb and 1,100 and 1,700 degrees C, respectively, for Cd. Characteristic masses (mo) were 10 and 0.4 pg for Pb and Cd, respectively. Precision of repeated analyses of calibration solutions was < or =3% relative standard deviation. Precision of duplicate leach solution analyses on different days was 0-9% relative difference. Recovery from fortified leach solutions was 96-106%. Results obtained by this method agreed 92-110% with those of confirmatory analyses. Results of certified reference material solutions agreed 94-100% with certificate values. Pb and Cd limits of quantitation (LOQ) were 0.005 and 0.0005 microg/mL, respectively. Results from 3 trial laboratories for 4 leach solutions containing Pb and Cd concentrations of 0.017-1.47 and <0.0005-0.0864 microg/mL, respectively, agreed 89-102% with results of the author. Two attributes of this method were noteworthy: (1) Background absorbance due to organic matter was entirely absent from atomization profiles, making the use of short pre-atomization hold times (2 s) possible. (2) Instrument precision was excellent and only one determination per solution was needed. Acceptance criteria for quality control measurements and a practical procedure for estimating the method LOQ during routine regulatory analyses

  7. [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.

  8. Direct solid-sampling electrothermal atomic absorption spectrometry methods for the determination of silicon in oxides of niobium, titanium and zirconium

    Science.gov (United States)

    Dong, Huang Mao; Krivan, Viliam

    2001-09-01

    An electrothermal atomic absorption spectrometer with a transversely heated graphite tube and a solid sampling system based on the boat technique was used for the development of methods for direct determination of silicon in powdered niobium pentoxide, titanium dioxide and zirconium dioxide. In the analysis of niobium pentoxide, serious matrix-caused non-spectral interferences and background were avoided by conversion of the niobium pentoxide matrix into the thermally stable niobium carbide using a methane atmosphere during the pyrolysis stage. For all three materials, calibration procedures using aqueous standard solutions were developed. For titanium dioxide and zirconium dioxide, the accuracy was checked by comparison of the results with those of independent methods, whereby good agreement was achieved. Owing to the high applicable sample amount per atomization (3-15 mg) and almost complete freedom of interference from the blank, limits of detection at the 10-ng g -1 level were achieved.

  9. [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.

  10. Determination of some heavy metal levels in soft drinks on the Ghanaian market using atomic absorption spectrometry method.

    Science.gov (United States)

    Ackah, Michael; Anim, Alfred Kwablah; Zakaria, Nafisatu; Osei, Juliet; Saah-Nyarko, Esther; Gyamfi, Eva Tabuaa; Tulasi, Delali; Enti-Brown, Sheriff; Hanson, John; Bentil, Nash Owusu

    2014-12-01

    Twenty-three soft drink samples (i.e., four pineapple-based fruit drinks, eight citrus-based fruit juices, one soya-based drink, three cola carbonated drinks, one apple-based fruit drink, and six cocktail fruit drinks) were randomly purchased from retail outlets in an urban market in Accra and analyzed for the concentrations of iron, cobalt, cadmium, zinc, lead, and copper using flame atomic absorption spectrometry. The mean concentration of iron and cadmium were 0.723 ± 0.448 mg/L and 0.032 ± 0.012 mg/L, respectively. The mean cobalt concentration was 0.071 ± 0.049 mg/L, while the mean Zn concentration in the samples was 0.060 ± 0.097 mg/L. The mean concentrations of Pb and Cu in the fruit juice samples were 0.178 ± 0.091 mg/L and 0.053 ± 0.063 mg/L respectively. About 78 % of the samples exceeded the United States Environmental Protection Agency (USEPA) maximum contaminant level of 0.3 mg/L prescribed for iron, whereas all the samples exceeded the USEPA maximum contaminant level of 0.005 mg/L prescribed for cadmium. About 91 % of the samples exceeded the EU maximum contaminant level prescribed for lead insoft drinks.

  11. Determination of cations and metals in samples of beer and raw materials for beer production by ion chromatography (IC) and atomic absorption spectrophotometry (AAS) methods

    OpenAIRE

    Rajković, Miloš B.; Sredović-Ignjatović, Ivana; Ignjatović, Ljubiša; Nedović, Viktor; Prijić, Slobodan

    2015-01-01

    In order to control the quality of beer and raw materials for beer production, methods as ion chromatography (IC) and atomic absorption spectrophotometry (AAS) were applied. Water was analyzed as a raw material for beer production (urban, technological and demineralized water). Measurements of pH values indicated the increased pH values in the sample of tehnological water, but it had no impact on wort hopping, since the tested samples of wort, young beer and final product had a pH value in th...

  12. Absorption imaging of ultracold atoms on atom chips

    DEFF Research Database (Denmark)

    Smith, David A.; Aigner, Simon; Hofferberth, Sebastian

    2011-01-01

    Imaging ultracold atomic gases close to surfaces is an important tool for the detailed analysis of experiments carried out using atom chips. We describe the critical factors that need be considered, especially when the imaging beam is purposely reflected from the surface. In particular we present...... methods to measure the atom-surface distance, which is a prerequisite for magnetic field imaging and studies of atom surface-interactions....

  13. Ionic liquid ultrasound assisted dispersive liquid-liquid microextraction method for preconcentration of trace amounts of rhodium prior to flame atomic absorption spectrometry determination

    Energy Technology Data Exchange (ETDEWEB)

    Molaakbari, Elaheh [Chemistry Department, Shahid Bahonar University of Kerman, Kerman (Iran, Islamic Republic of); Young Research Society, Shahid Bahonar University of Kerman, Kerman (Iran, Islamic Republic of); Mostafavi, Ali, E-mail: mostafavi.ali@gmail.com [Chemistry Department, Shahid Bahonar University of Kerman, Kerman (Iran, Islamic Republic of); Afzali, Daryoush [Environment and Nanochemistry Department, Research Institute of Environmental Science, International Center for Science, High Technology and Environmental Science, Kerman (Iran, Islamic Republic of); Mineral Industries Research Center, Shahid Bahonar University of Kerman, Kerman (Iran, Islamic Republic of)

    2011-01-30

    In this article, we consider ionic liquid based ultrasound-assisted dispersive liquid-liquid microextraction of trace amounts of rhodium from aqueous samples and show that this is a fast and reliable sample pre-treatment for the determination of rhodium ions by flame atomic absorption spectrometry. The Rh(III) was transferred into its complex with 2-(5-bromo-2-pyridylazo)-5-diethylamino phenol as a chelating agent, and an ultrasonic bath with the ionic liquid, 1-octyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide at room temperature was used to extract the analyte. The centrifuged rhodium complex was then enriched in the form of ionic liquid droplets and prior to its analysis by flame atomic absorption spectrometry, 300 {mu}L ethanol was added to the ionic liquid-rich phase. Finally, the influence of various parameters on the recovery of Rh(III) was optimized. Under optimum conditions, the calibration graph was linear in the range of 4.0-500.0 ng mL{sup -1}, the detection limit was 0.37 ng mL{sup -1} (3S{sub b}/m, n = 7) and the relative standard deviation was {+-}1.63% (n = 7, C = 200 ng mL{sup -1}). The results show that ionic liquid based ultrasound assisted dispersive liquid-liquid microextraction, combined with flame atomic absorption spectrometry, is a rapid, simple, sensitive and efficient analytical method for the separation and determination of trace amounts of Rh(III) ions with minimum organic solvent consumption.

  14. Validation of a method to quantify chromium, cadmium, manganese, nickel and lead in human whole blood, urine, saliva and hair samples by electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Olmedo, P.; Pla, A.; Hernandez, A.F.; Lopez-Guarnido, O.; Rodrigo, L. [Department of Legal Medicine and Toxicology, University of Granada, School of Medicine (Spain); Gil, F., E-mail: fgil@ugr.es [Department of Legal Medicine and Toxicology, University of Granada, School of Medicine (Spain)

    2010-02-05

    For biological monitoring of heavy metal exposure in occupational toxicology, usually whole blood and urine samples are the most widely used and accepted matrix to assess internal xenobiotic exposure. Hair samples and saliva are also of interest in occupational and environmental health surveys but procedures for the determination of metals in saliva and hair are very scarce and to our knowledge there is no validation of a method to quantify Cr, Cd, Mn, Ni and Pb in four different human biological materials (whole blood, urine, saliva and axilary hair) by electrothermal atomization atomic absorption spectrometry (ETAAS). In the present study, quantification methods for the determination of Cr, Cd, Mn, Ni and Pb in whole blood, urine, saliva and axilary hair were validated according to the EU common standards. Pyrolisis and atomization temperatures have been determined. The main parameters evaluated were: detection and quantification limits, linearity range, repeatability, reproducibility, recovery and uncertainty. Accuracy of the methods was tested with the whole blood, urine and hair certified reference materials and recoveries of the spiked samples were acceptable ranged from 96.3 to 107.8%.

  15. Validation of a method to quantify chromium, cadmium, manganese, nickel and lead in human whole blood, urine, saliva and hair samples by electrothermal atomic absorption spectrometry.

    Science.gov (United States)

    Olmedo, P; Pla, A; Hernández, A F; López-Guarnido, O; Rodrigo, L; Gil, F

    2010-02-05

    For biological monitoring of heavy metal exposure in occupational toxicology, usually whole blood and urine samples are the most widely used and accepted matrix to assess internal xenobiotic exposure. Hair samples and saliva are also of interest in occupational and environmental health surveys but procedures for the determination of metals in saliva and hair are very scarce and to our knowledge there is no validation of a method to quantify Cr, Cd, Mn, Ni and Pb in four different human biological materials (whole blood, urine, saliva and axilary hair) by electrothermal atomization atomic absorption spectrometry (ETAAS). In the present study, quantification methods for the determination of Cr, Cd, Mn, Ni and Pb in whole blood, urine, saliva and axilary hair were validated according to the EU common standards. Pyrolisis and atomization temperatures have been determined. The main parameters evaluated were: detection and quantification limits, linearity range, repeatability, reproducibility, recovery and uncertainty. Accuracy of the methods was tested with the whole blood, urine and hair certified reference materials and recoveries of the spiked samples were acceptable ranged from 96.3 to 107.8%.

  16. Development of a simple method for the determination of lead in lipstick using alkaline solubilization and graphite furnace atomic absorption spectrometry.

    Science.gov (United States)

    Soares, Aline Rodrigues; Nascentes, Clésia Cristina

    2013-02-15

    A simple method was developed for determining the total lead content in lipstick samples by graphite furnace atomic absorption spectrometry (GFAAS) after treatment with tetramethylammonium hydroxide (TMAH). Multivariate optimization was used to establish the optimal conditions of sample preparation. The graphite furnace heating program was optimized through pyrolysis and atomization curves. An aliquot containing approximately 50mg of the sample was mixed with TMAH and heated in a water bath at 60°C for 60 min. Using Nb as the permanent modifier and Pd as the chemical modifier, the optimal temperatures were 900°C and 1800°C for pyrolysis and atomization, respectively. Under optimum conditions, the working range was from 1.73 to 50.0 μg L(-1), with detection and quantification limits of 0.20 and 0.34 μg g(-1), respectively. The precision was evaluated under conditions of repeatability and intermediate precision and showed standard deviations of 2.37%-4.61% and 4.93%-9.75%, respectively. The % recovery ranged from 96.2% to 109%, and no significant differences were found between the results obtained using the proposed method and the microwave decomposition method for real samples. Lead was detected in 21 tested lipstick samples; the lead content in these samples ranged from 0.27 to 4.54 μg g(-1). Copyright © 2012 Elsevier B.V. All rights reserved.

  17. 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)

  18. Freon (CHF3)-assisted atomization for the determination of titanium using ultrasonic slurry sampling-graphite furnace atomic absorption spectrometry (USS-GFAAS): a simple and advantageous method for solid samples.

    Science.gov (United States)

    Asfaw, Alemayehu; Wibetoe, Grethe

    2004-06-01

    A simple and advantageous method for the determination of titanium using graphite furnace atomic absorption spectrometry with slurry sampling has been developed. Titanium is one of the refractory elements that form thermally stable carbides in the graphite tube, which leads to severe memory effects. Trifluoromethane (Freon-23) was applied in the purge gas during the atomization step or alternatively just prior to the atomization to successfully eliminate the problems of carbide formation and increase the lifetime of the furnace tube which could be used for more than 600 heating cycles. A flow rate of 40 mL min(-1) (5% of Freon in argon) was used to obtain symmetrical peaks with no tailing. However, when the gas flow rate was too high (250 mL min(-1)) the peak-tailing and memory effects reappeared. Ti was determined in various materials covering a wide range of concentrations, from 2.8 microg g(-1) to 12% (m/m) Ti. The accuracy of the method was confirmed by analyzing certified reference materials (CRMs) or by comparing the results with those obtained using inductively coupled plasma-atomic emission spectrometry (ICP-AES) after decomposition of the samples. The materials analyzed were soil, plant, human hair, coal, urban particulate matters, toothpaste, and powdered paint.

  19. Study of the versatility of a graphite furnace atomic absorption spectrometric method for the determination of cadmium in the environmental field

    Energy Technology Data Exchange (ETDEWEB)

    Rucandio, M.I.; Petit-Dominguez, M.D. [CIEMAT, Madrid (Spain)

    2002-07-01

    This paper describes a versatile method for the determination of Cd at various levels (0.1-500 {mu}g/g) in several sample types, such as soils, sediments, coals, ashes, sewage sludges, animal tissues, and plants, by graphite furnace atomic absorption spectrometry with Zeeman background correction. The effect of the individual presence of about 50 elements, with an interference/analyte concentration ratio of up to 10{sup 5}, was tested; recoveries of Cd ranged from 93 to 106%. The influence of different media, such as HNO{sub 3}, HCl, HF, H{sub 2}SO{sub 4}, HClO{sub 4}, acetic acid, hydroxylammonium chloride, and ammonium acetate, in several concentrations, was also tested. From these studies it can be concluded that the analytical procedure is scarcely matrix dependent, and the results obtained for a wide diversity of reference materials are in good agreement with the certified values.

  20. An improved method for the determination of trace levels of arsenic and antimony in geological materials by automated hydride generation-atomic absorption spectroscopy

    Science.gov (United States)

    Crock, J.G.; Lichte, F.E.

    1982-01-01

    An improved, automated method for the determination of arsenic and antimony in geological materials is described. After digestion of the material in sulfuric, nitric, hydrofluoric and perchloric acids, a hydrochloric acid solution of the sample is automatically mixed with reducing agents, acidified with additional hydrochloric acid, and treated with a sodium tetrahydroborate solution to form arsine and stibine. The hydrides are decomposed in a heated quartz tube in the optical path of an atomic absorption spectrometer. The absorbance peak height for arsenic or antimony is measured. Interferences that exist are minimized to the point where most geological materials including coals, soils, coal ashes, rocks and sediments can be analyzed directly without use of standard additions. The relative standard deviation of the digestion and the instrumental procedure is less than 2% at the 50 ??g l-1 As or Sb level. The reagent-blank detection limit is 0.2 ??g l-1 As or Sb. ?? 1982.

  1. 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.

  2. [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.

  3. Monitoring and Method development of Hg in Istanbul Airborne Particulates by Solid Sampling Continuum Source-High Resolution Electrothermal Atomic Absorption Spectromerty

    Directory of Open Access Journals (Sweden)

    Soydemir E.

    2014-07-01

    Full Text Available In this work, a method has been developed and monitoring for the determination of mercury in PM2.5 airborne particulates by solid sampling high-resolution continuum source electrothermal atomic absorption spectrometry. The PM2.5 airborne particulates were collected on quartz filters using high volume samplers (500 L/min in Istanbul (Turkey for 96 hours every month in one year. At first, experimental conditions as well as the validation tests were optimized using collected filter. For this purpose, the effects of atomization temperature, amount of sample intoduced in to the furnace, addition of acids and/or KMnO4 on the sample, covering of graphite tube and platform or using of Ag nanoparticulates, Au nanoparticulates, and Pd solutions on the accuracy and precision were investigated. After optimization of the experimental conditions, the mercury concentrations were determined in the collected filter. The filters with PM2.5 airborne particulates were dried, divided into small fine particles and then Hg concentrations were determined directly. In order to eliminate any error due to the sensitivity difference between aqueous standards and solid samples, the quantification was performed using solid calibrants. The limit of detection, based on three times the standard deviations for ten atomizations of an unused filter, was 30 ng/g. The Hg content was dependent on the sampling site, season etc, ranging from

  4. 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.

  5. 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.

  6. Validated method for the determination of platinum from a liposomal source (SPI-77) in human plasma using graphite furnace Zeeman atomic absorption spectrometry.

    Science.gov (United States)

    Meerum Terwogt, J M; Tibben, M M; Welbank, H; Schellens, J H; Beijnen, J H

    2000-02-01

    A sensitive analytical method based on flameless atomic absorption spectrometry with Zeeman correction has been validated for the quantitative determination in human plasma of platinum originating from cisplatin in a liposomal source, SPI-77. The performance of the method was acceptable over a sample concentration range of 0. 125-1.25 micromol platinum/L and the lower limit of quantification was determined to be 1.25 micromol platinum/L in undiluted clinical samples. The performance data of the assay were investigated using both a calibration curve with carboplatin in plasma ultrafiltrate and diluted human plasma samples spiked with SPI-77. The recoveries, between-day and the within-day precisions of both methods of calibration were not significantly different allowing carboplatin ultrafiltrate calibration standards to be used to quantify platinum derived from SPI-77 in human plasma. Apparently, the liposomal formulation had no significant influence on the determination of platinum. The usefulness of the presented method was demonstrated in a phase I clinical and pharmacokinetic study. In addition, in vitro experiments were carried out to determine the distribution of SPI-77 in blood. The results indicated that platinum from SPI-77 mainly concentrates in plasma and that binding to and/or endocytosis in red blood cells is negligible.

  7. Determination of Iron (Fe and Calcium (Ca in NIST SRM 1566b (Oyster tissue using Flame Atomic Absorption Spectrometry (F-AAS by Standard Addition Method

    Directory of Open Access Journals (Sweden)

    Fitri Dara

    2017-03-01

    Full Text Available NIST Standard Reference Material (SRM 1566b was employed for the determination of Iron (Fe andCalcium (Ca as nutrients in food matrix using Flame Atomic Absorption Spectrometry (F-AAS. Thecertified value of SRM 1566b for Fe and Ca are 205.8 ± 6.8 mg/kg and 0.0838 ± 0.0020 (% or 838 ±20 mg/kg, respectively. This certified values are based on results obtained by single primary method(Isotope Dilution Inductively Couple Plasma Mass Spectrometry at NIST with confirmation by othermethods at National Metrology Institute of P.R. China. This paper proposed a method fordetermination of Fe and Ca in food matrix as recommended by AOAC official with a littlemodification. The method was commenced from the destruction of all organic matter by dry oxidationbefore analysis by standard addition. Under optimum condition, the results of the determination of Feand Ca in SRM 1566b were agreed well with the certificate value. This method would be useful forroutine analysis in food testing laboratories.

  8. EPA Method 3031 (SW-846): Acid Digestion of Oils for Metals Analysis by Atomic Absorption or ICP Spectrometry

    Science.gov (United States)

    Procedures are described for analysis of water samples and may be adapted for assessment of solid, particulate and liquid samples. The method uses real-time PCR assay for detecting Toxoplasma gondii DNA using gene-specific primers and probe.

  9. Trace mercury determination in drinking and natural water after preconcentration and separation by DLLME-SFO method coupled with cold vapor atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    Abdollahi Atousa

    2014-07-01

    Full Text Available A novel dispersive liquid–liquid microextraction based on solidification of floating organic drop (DLLME-SFO for simultaneous separation/preconcentration of ultra trace amounts of mercury was used. A method based on amalgamation was used for collection of gaseous mercury on gold coated sand (Gold trap. The concentration of mercury was determined by cold vapor atomic absorption spectrometry (CV-AAS. The DLLME-SFO behavior of mercury by using dithizone as complexing agent was systematically investigated. The factors influencing, the complex formation and extraction of DLLME-SFO method such as type and volume of extraction and disperser solvents, pH, concentration of salt, centrifuging time and concentration of the chelating agent were optimized. The method was successfully applied to the determination of mercury in drinking and natural water and satisfactory relative recoveries (95–105% were achieved. The proposed procedure was based on very low consumption of organic solvents. The other benefits of the system were sensitive, simple, friendly to the environment, rejection of matrix constituent, low cost, the time consuming and high enrichment factor.

  10. 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).

  11. An atomic absorption spectrometric method for the determination of phosphorus in foodstuffs using the bismuth phosphomolybdate complex

    Directory of Open Access Journals (Sweden)

    LJILJANA V. MIHAJLOVIC

    2000-06-01

    Full Text Available A new indirect AAS method using the bismuth phosphomolybdate complex for the determination of phosphorus in foodstuffs is suggested. The bismuth phosphomolybdate complex in acid medium was extacted with isobutyl methylketone and the phosphorus was determined through bismuth in an air/acetylene flame by utilising the 223.06 nm resonance line of bismuth. The interference caused by antimony and titanium can be neglected in the presence of excess of bismuth. The detection limit of the method is 0.008 mg/mL of phosphorus.

  12. 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.

  13. 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.

  14. A rapid method for determining tin and molybdenum in geological samples by flame atomic-absorption spectroscopy

    Science.gov (United States)

    Welsch, E.P.

    1985-01-01

    The proposed method uses a lithium metaborate fusion, dissolution of the fusion bead in 15% v v hydrochloric acid, extraction into a 4% solution of trioctylphosphine oxide in methyl isobutyl ketone, and aspiration into a nitrous oxide-acetylene flame. The limits of detection for tin and molybdenum are 1.0 and 0.5 ppm, respectively. Approximately 50 samples can be analysed per day. ?? 1985.

  15. Method validation for control determination of mercury in fresh fish and shrimp samples by solid sampling thermal decomposition/amalgamation atomic absorption spectrometry.

    Science.gov (United States)

    Torres, Daiane Placido; Martins-Teixeira, Maristela Braga; Cadore, Solange; Queiroz, Helena Müller

    2015-01-01

    A method for the determination of total mercury in fresh fish and shrimp samples by solid sampling thermal decomposition/amalgamation atomic absorption spectrometry (TDA AAS) has been validated following international foodstuff protocols in order to fulfill the Brazilian National Residue Control Plan. The experimental parameters have been previously studied and optimized according to specific legislation on validation and inorganic contaminants in foodstuff. Linearity, sensitivity, specificity, detection and quantification limits, precision (repeatability and within-laboratory reproducibility), robustness as well as accuracy of the method have been evaluated. Linearity of response was satisfactory for the two range concentrations available on the TDA AAS equipment, between approximately 25.0 and 200.0 μg kg(-1) (square regression) and 250.0 and 2000.0 μg kg(-1) (linear regression) of mercury. The residues for both ranges were homoscedastic and independent, with normal distribution. Correlation coefficients obtained for these ranges were higher than 0.995. Limits of quantification (LOQ) and of detection of the method (LDM), based on signal standard deviation (SD) for a low-in-mercury sample, were 3.0 and 1.0 μg kg(-1), respectively. Repeatability of the method was better than 4%. Within-laboratory reproducibility achieved a relative SD better than 6%. Robustness of the current method was evaluated and pointed sample mass as a significant factor. Accuracy (assessed as the analyte recovery) was calculated on basis of the repeatability, and ranged from 89% to 99%. The obtained results showed the suitability of the present method for direct mercury measurement in fresh fish and shrimp samples and the importance of monitoring the analysis conditions for food control purposes. Additionally, the competence of this method was recognized by accreditation under the standard ISO/IEC 17025.

  16. 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.

  17. 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.

  18. 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.

  19. 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

  20. Accuracy of a method based on atomic absorption spectrometry to determine inorganic arsenic in food: Outcome of the collaborative trial IMEP-41.

    Science.gov (United States)

    Fiamegkos, I; Cordeiro, F; Robouch, P; Vélez, D; Devesa, V; Raber, G; Sloth, J J; Rasmussen, R R; Llorente-Mirandes, T; Lopez-Sanchez, J F; Rubio, R; Cubadda, F; D'Amato, M; Feldmann, J; Raab, A; Emteborg, H; de la Calle, M B

    2016-12-15

    A collaborative trial was conducted to determine the performance characteristics of an analytical method for the quantification of inorganic arsenic (iAs) in food. The method is based on (i) solubilisation of the protein matrix with concentrated hydrochloric acid to denature proteins and allow the release of all arsenic species into solution, and (ii) subsequent extraction of the inorganic arsenic present in the acid medium using chloroform followed by back-extraction to acidic medium. The final detection and quantification is done by flow injection hydride generation atomic absorption spectrometry (FI-HG-AAS). The seven test items used in this exercise were reference materials covering a broad range of matrices: mussels, cabbage, seaweed (hijiki), fish protein, rice, wheat, mushrooms, with concentrations ranging from 0.074 to 7.55mgkg(-1). The relative standard deviation for repeatability (RSDr) ranged from 4.1 to 10.3%, while the relative standard deviation for reproducibility (RSDR) ranged from 6.1 to 22.8%.

  1. An analytical method for determination of mercury by cold vapor atomic absorption spectroscopy; Determinazione di mercurio. Metodo per spettrometria di assorbimento atomico a vapori freddi (CV-AAS)

    Energy Technology Data Exchange (ETDEWEB)

    Campanella, L. [Rome Univ. La Sapienza, Rome (Italy); Mastroianni, D.; Capri, S.; Pettine, M. [CNR, Rome (Italy). Ist. di Ricerca sulle Acque; Spezia, S.; Bettinelli, M. [ENEL, Unified Modelling Language, Piacenza (Italy)

    1999-09-01

    An analytical procedure for the determination of total mercury in wastewaters and natural waters is described. Aqueous samples are fast digested with nitric acid by using the microwave-oven technique; the analysis of mercury is then performed by cold vapor atomic absorption spectrometry (CV-AAS) using two possible instrumental apparatus (batch system or flow injection). Sodium borohydride is used as the reducing agent for mercury in solution (Method A). The use of amalgamation traps on gold for the preconcentration of mercury lowers the detection limit of the analyte (Method B). [Italian] Viene descritta una procedura analitica per la determinazione del mercurio totale in acque di scarico e naturali. Il campione acquoso viene sottoposto a mineralizzazione con acido nitrico in forno a microonde e analizzato mediante spettroscopia di assorbimento atomico a vapori freddi (CV-AAS) in due possibili configurazioni strumentali (sistema batch oppure flow injection), utilizzando sodio boro idruro come agente riducente del mercurio (metodo A). L'impiego della trappola di oro per la preconcentrazione del mercurio mediante amalgama consente di determinare l'analita a livelli di pochi ng/L (metodo B).

  2. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of antimony by automated-hydride atomic absorption spectrophotometry

    Science.gov (United States)

    Brown, G.E.; McLain, B.J.

    1994-01-01

    The analysis of natural-water samples for antimony by automated-hydride atomic absorption spectrophotometry is described. Samples are prepared for analysis by addition of potassium and hydrochloric acid followed by an autoclave digestion. After the digestion, potassium iodide and sodium borohydride are added automatically. Antimony hydride (stibine) gas is generated, then swept into a heated quartz cell for determination of antimony by atomic absorption spectrophotometry. Precision and accuracy data are presented. Results obtained on standard reference water samples agree with means established by interlaboratory studies. Spike recoveries for actual samples range from 90 to 114 percent. Replicate analyses of water samples of varying matrices give relative standard deviations from 3 to 10 percent.

  3. X-ray absorption near edge structure/electron energy loss near edge structure calculation using the supercell orthogonalized linear combination of atomic orbitals method.

    Science.gov (United States)

    Ching, Wai-Yim; Rulis, Paul

    2009-03-11

    Over the last eight years, a large number of x-ray absorption near edge structure (XANES) and/or electron energy loss near edge structure (ELNES) spectroscopic calculations for complex oxides and nitrides have been performed using the supercell-OLCAO (orthogonalized linear combination of atomic orbitals) method, obtaining results in very good agreement with experiments. The method takes into account the core-hole effect and includes the dipole matrix elements calculated from ab initio wavefunctions. In this paper, we describe the method in considerable detail, emphasizing the special advantages of this method for large complex systems. Selected results are reviewed and several hitherto unpublished results are also presented. These include the Y K edge of Y ions segregated to the core of a Σ31 grain boundary in alumina, O K edges of water molecules, C K edges in different types of single walled carbon nanotubes, and the Co K edge in the cyanocobalamin (vitamin B(12)) molecule. On the basis of these results, it is argued that the interpretation of specific features of the calculated XANES/ELNES edges is not simple for complex material systems because of the delocalized nature of the conduction band states. The long-standing notion of the 'fingerprinting' technique for spectral interpretation of experimental data is not tenable. A better approach is to fully characterize the structure under study, using either crystalline data or accurate ab initio modeling. Comparison between calculated XANES/ELNES spectra and available measurements enables us to ascertain the validity of the modeled structure. For complex crystals or structures, it is necessary to use the weighted sum of the spectra from structurally nonequivalent sites for comparison with the measured data. Future application of the supercell-OLCAO method to complex biomolecular systems is also discussed.

  4. X-ray absorption near edge structure/electron energy loss near edge structure calculation using the supercell orthogonalized linear combination of atomic orbitals method

    Energy Technology Data Exchange (ETDEWEB)

    Ching, W.-Y.; Rulis, Paul [Department of Physics, University of Missouri-Kansas City, Kansas City, MO 64110 (United States)

    2009-03-11

    Over the last eight years, a large number of x-ray absorption near edge structure (XANES) and/or electron energy loss near edge structure (ELNES) spectroscopic calculations for complex oxides and nitrides have been performed using the supercell-OLCAO (orthogonalized linear combination of atomic orbitals) method, obtaining results in very good agreement with experiments. The method takes into account the core-hole effect and includes the dipole matrix elements calculated from ab initio wavefunctions. In this paper, we describe the method in considerable detail, emphasizing the special advantages of this method for large complex systems. Selected results are reviewed and several hitherto unpublished results are also presented. These include the Y K edge of Y ions segregated to the core of a {sigma}31 grain boundary in alumina, O K edges of water molecules, C K edges in different types of single walled carbon nanotubes, and the Co K edge in the cyanocobalamin (vitamin B{sub 12}) molecule. On the basis of these results, it is argued that the interpretation of specific features of the calculated XANES/ELNES edges is not simple for complex material systems because of the delocalized nature of the conduction band states. The long-standing notion of the 'fingerprinting' technique for spectral interpretation of experimental data is not tenable. A better approach is to fully characterize the structure under study, using either crystalline data or accurate ab initio modeling. Comparison between calculated XANES/ELNES spectra and available measurements enables us to ascertain the validity of the modeled structure. For complex crystals or structures, it is necessary to use the weighted sum of the spectra from structurally nonequivalent sites for comparison with the measured data. Future application of the supercell-OLCAO method to complex biomolecular systems is also discussed.

  5. X-ray absorption near edge structure/electron energy loss near edge structure calculation using the supercell orthogonalized linear combination of atomic orbitals method

    Science.gov (United States)

    Ching, Wai-Yim; Rulis, Paul

    2009-03-01

    Over the last eight years, a large number of x-ray absorption near edge structure (XANES) and/or electron energy loss near edge structure (ELNES) spectroscopic calculations for complex oxides and nitrides have been performed using the supercell-OLCAO (orthogonalized linear combination of atomic orbitals) method, obtaining results in very good agreement with experiments. The method takes into account the core-hole effect and includes the dipole matrix elements calculated from ab initio wavefunctions. In this paper, we describe the method in considerable detail, emphasizing the special advantages of this method for large complex systems. Selected results are reviewed and several hitherto unpublished results are also presented. These include the Y K edge of Y ions segregated to the core of a Σ31 grain boundary in alumina, O K edges of water molecules, C K edges in different types of single walled carbon nanotubes, and the Co K edge in the cyanocobalamin (vitamin B12) molecule. On the basis of these results, it is argued that the interpretation of specific features of the calculated XANES/ELNES edges is not simple for complex material systems because of the delocalized nature of the conduction band states. The long-standing notion of the 'fingerprinting' technique for spectral interpretation of experimental data is not tenable. A better approach is to fully characterize the structure under study, using either crystalline data or accurate ab initio modeling. Comparison between calculated XANES/ELNES spectra and available measurements enables us to ascertain the validity of the modeled structure. For complex crystals or structures, it is necessary to use the weighted sum of the spectra from structurally nonequivalent sites for comparison with the measured data. Future application of the supercell-OLCAO method to complex biomolecular systems is also discussed.

  6. Method development for the determination of fluorine in water samples via the molecular absorption of strontium monofluoride formed in an electrothermal atomizer

    Energy Technology Data Exchange (ETDEWEB)

    Ozbek, Nil, E-mail: nil.ozbek@itu.edu.tr; Akman, Suleyman, E-mail: akmans@itu.edu.tr

    2012-03-15

    The presence of fluorine (F) was detected via the rotational molecular absorption line of diatomic strontium-monofluoride (SrF) generated in the gas phase at 651.187 nm using high-resolution continuum source electrothermal atomic absorption spectrometry. Upon the addition of excess strontium (Sr) as the nitrate, the fluorine in the sample was converted to SrF in the gas phase of a graphite furnace. The effects on the accuracy, precision and sensitivity of variables such as the SrF wavelength, graphite furnace program, amount of Sr, coating of the graphite tube and platform with Zr and Ir and the use of a modifier were investigated and optimized. It was determined that there was no need to use a modifier or to cover the platform/tubes with Zr or Ir. Fluorine concentrations in various water samples (certified waste water, tap water, drinking water and mineral water) were determined using 20 {mu}g of Sr as the molecule-forming reagent and applying a maximum pyrolysis temperature of 800 Degree-Sign C and a molecule-forming temperature of 2200 Degree-Sign C with a heating rate of 2000 Degree-Sign C s{sup -1}. Good linearity was maintained up to 0.1 {mu}g of F. The accuracy and precision of the method were tested by analyzing certified reference wastewater. The results were in good agreement with certified values, and the precision was satisfactory (RSD < 10%). The limit of detection and the characteristic mass for the method were 0.36 ng and 0.55 ng, respectively. Finally, the fluorine concentrations in several drinking water and mineral water samples taken from the market were determined. The results were in good agreement with the values supplied by the producers. No significant differences were found between the results from the linear calibration and standard addition techniques. The method was determined to be simple, fast, accurate and sensitive. - Highlights: Black-Right-Pointing-Pointer F is determined via MAS of SrF at 651.187 nm using HR-CS-ET AAS. Black

  7. Solid phase extraction method for the determination of iron, lead and chromium by atomic absorption spectrometry using Amberite XAD-2000 column in various water samples

    Energy Technology Data Exchange (ETDEWEB)

    Elci, Latif [Chemistry Department, Science and Arts Faculty, Pamukkale University, Denizli (Turkey)], E-mail: elci@pamukkale.edu.tr; Kartal, Aslihan A. [Chemistry Department, Science and Arts Faculty, Pamukkale University, Denizli (Turkey); Soylak, Mustafa [Chemistry Department, Science and Arts Faculty, Erciyes University, Kayseri (Turkey)

    2008-05-01

    This work describes a procedure for the separation-preconcentration of Fe(III), Pb(II) and Cr(III) from some water samples using a column-filled Amberlite XAD-2000 resin. The analyte ions retained on the column were eluted with 0.5 mol L{sup -1} HNO{sub 3}. The analytes in the effluent were determined by atomic absorption spectrometry. Several parameters governing the efficiency of the method were evaluated including pH, resin amount, sample volume, flow rates, eluent type and divers ion effects. The recoveries under the optimum working conditions were found to be as 100 {+-} 1% Fe, 96 {+-} 1% Pb and 93 {+-} 2% Cr. The relative standard deviations and errors were less than 2% and 5%, respectively. The detection limit based on three standard deviations of the blank was found to be 0.32, 0.51 and 0.81 {mu}g L{sup -1}, for Fe, Pb and Cr, respectively. The procedure was applied to the determination of Fe, Cr and Pb in hot spring water and drinking water samples.

  8. Solid phase extraction method for the determination of iron, lead and chromium by atomic absorption spectrometry using Amberite XAD-2000 column in various water samples.

    Science.gov (United States)

    Elci, Latif; Kartal, Aslihan A; Soylak, Mustafa

    2008-05-01

    This work describes a procedure for the separation-preconcentration of Fe(III), Pb(II) and Cr(III) from some water samples using a column-filled Amberlite XAD-2000 resin. The analyte ions retained on the column were eluted with 0.5 mol L(-1) HNO(3). The analytes in the effluent were determined by atomic absorption spectrometry. Several parameters governing the efficiency of the method were evaluated including pH, resin amount, sample volume, flow rates, eluent type and divers ion effects. The recoveries under the optimum working conditions were found to be as 100+/-1% Fe, 96+/-1% Pb and 93+/-2% Cr. The relative standard deviations and errors were less than 2% and 5%, respectively. The detection limit based on three standard deviations of the blank was found to be 0.32, 0.51 and 0.81 microg L(-1), for Fe, Pb and Cr, respectively. The procedure was applied to the determination of Fe, Cr and Pb in hot spring water and drinking water samples.

  9. 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

  10. 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.

  11. 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.

  12. Method development for the control determination of mercury in seafood by solid-sampling thermal decomposition amalgamation atomic absorption spectrometry (TDA AAS).

    Science.gov (United States)

    Torres, D P; Martins-Teixeira, M B; Silva, E F; Queiroz, H M

    2012-01-01

    A very simple and rapid method for the determination of total mercury in fish samples using the Direct Mercury Analyser DMA-80 was developed. In this system, a previously weighted portion of fresh fish is combusted and the released mercury is selectively trapped in a gold amalgamator. Upon heating, mercury is desorbed from the amalgamator, an atomic absorption measurement is performed and the mercury concentration is calculated. Some experimental parameters have been studied and optimised. In this study the sample mass was about 100.0 mg. The relative standard deviation was lower than 8.0% for all measurements of solid samples. Two calibration curves against aqueous standard solutions were prepared through the low linear range from 2.5 to 20.0 ng of Hg, and the high linear range from 25.0 to 200.0 ng of Hg, for which a correlation coefficient better than 0.997 was achieved, as well as a normal distribution of the residuals. Mercury reference solutions were prepared in 5.0% v/v nitric acid medium. Lyophilised fish tissues were also analysed; however, the additional procedure had no advantage over the direct analysis of the fresh fish, and additionally increased the total analytical process time. A fish tissue reference material, IAEA-407, was analysed and the mercury concentration was in agreement with the certified value, according to the t-test at a 95% confidence level. The limit of quantification (LOQ), based on a mercury-free sample, was 3.0 µg kg(-1). This LOQ is in accordance with performance criteria required by the Commission Regulation No. 333/2007. Simplicity and high efficiency, without the need for any sample preparation procedure, are some of the qualities of the proposed method.

  13. Development of a method for total Hg determination in oil samples by cold vapor atomic absorption spectrometry after its extraction induced by emulsion breaking.

    Science.gov (United States)

    Vicentino, Priscila de O; Brum, Daniel M; Cassella, Ricardo J

    2015-01-01

    This work reports the development of a novel extraction method for total Hg determination in oil samples. After extracting Hg from samples it was quantified in the extracts by cold vapor atomic absorption spectrometry (CV-AAS), employing a laboratory-made gas-liquid separator (GLS) and NaBH4 as reducing agent. The extraction of Hg from samples was carried out by extraction induced by emulsion breaking (EIEB), which is based on the formation and breaking of water-in-oil emulsion between the oil samples and an extractant solution containing an emulsifying agent (surfactant) and nitric acid. Operational parameters of the GLS were evaluated in order to set the best performance of the measurement system. In these studies it was proven that the volume of sample and the concentration of HCl added to the sample extracts had significant influence on Hg response. The best conditions were achieved by adding 0.5 mL of a 0.3 mol L(-1) HCl solution on 1 mL of sample extract. The extraction conditions were also optimized. The highest efficiency was observed when 4 mL of a solution containing 2.5% triton X-100 and 15% v/v HNO3 were employed for the extraction of Hg contained in 20 mL of sample. Emulsion breaking was performed by heating at 80 °C and took approximately 20 min. The limit of quantification of the method was 1.9 µg L(-1) and recovery percentages between 80% and 103% were observed when spiked samples (2 and 10 µg L(-1)) of diesel oil, biodiesel and mineral oil were analyzed.

  14. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of low-level silver by graphite furnace atomic absorption spectrophotometry

    Science.gov (United States)

    Damrau, D.L.

    1993-01-01

    Increased awareness of the quality of water in the United States has led to the development of a method for determining low levels (0.2-5.0 microg/L) of silver in water samples. Use of graphite furnace atomic absorption spectrophotometry provides a sensitive, precise, and accurate method for determining low-level silver in samples of low ionic-strength water, precipitation water, and natural water. The minimum detection limit determined for low-level silver is 0.2 microg/L. Precision data were collected on natural-water samples and SRWS (Standard Reference Water Samples). The overall percent relative standard deviation for natural-water samples with silver concentrations more than 0.2 microg/L was less than 40 percent throughout the analytical range. For the SRWS with concentrations more than 0.2 microg/L, the overall percent relative standard deviation was less than 25 percent throughout the analytical range. The accuracy of the results was determined by spiking 6 natural-water samples with different known concentrations of the silver standard. The recoveries ranged from 61 to 119 percent at the 0.5-microg/L spike level. At the 1.25-microg/L spike level, the recoveries ranged from 92 to 106 percent. For the high spike level at 3.0 microg/L, the recoveries ranged from 65 to 113 percent. The measured concentrations of silver obtained from known samples were within the Branch of Quality Assurance accepted limits of 1 1/2 standard deviations on the basis of the SRWS program for Inter-Laboratory studies.

  15. Method development and optimization for the determination of selenium in bean and soil samples using hydride generation electrothermal atomic absorption spectrometry.

    Science.gov (United States)

    Shaltout, Abdallah A; Castilho, Ivan N B; Welz, Bernhard; Carasek, Eduardo; Martens, Irland B Gonzaga; Martens, Andreas; Cozzolino, Silvia M F

    2011-09-15

    The present investigation is the first part of an initiative to prepare a regional map of the natural abundance of selenium in various areas of Brazil, based on the analysis of bean and soil samples. Continuous-flow hydride generation electrothermal atomic absorption spectrometry (HG-ET AAS) with in situ trapping on an iridium-coated graphite tube has been chosen because of the high sensitivity and relative simplicity. The microwave-assisted acid digestion for bean and soil samples was tested for complete recovery of inorganic and organic selenium compounds (selenomethionine). The reduction of Se(VI) to Se(IV) was optimized in order to guarantee that there is no back-oxidation, which is of importance when digested samples are not analyzed immediately after the reduction step. The limits of detection and quantification of the method were 30 ng L(-1) Se and 101 ng L(-1) Se, respectively, corresponding to about 3 ng g(-1) and 10 ng g(-1), respectively, in the solid samples, considering a typical dilution factor of 100 for the digestion process. The results obtained for two certified food reference materials (CRM), soybean and rice, and for a soil and sediment CRM confirmed the validity of the investigated method. The selenium content found in a number of selected bean samples varied between 5.5±0.4 ng g(-1) and 1726±55 ng g(-1), and that in soil samples varied between 113±6.5 ng g(-1) and 1692±21 ng g(-1).

  16. 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.

  17. Method development for the determination of cadmium in fertilizer samples using high-resolution continuum source graphite furnace atomic absorption spectrometry and slurry sampling

    Energy Technology Data Exchange (ETDEWEB)

    Borges, Aline R. [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 de Bahia, Salvador, BA (Brazil); Becker, Emilene M. [Instituto de Quimica, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves 9500, 91501-970 Porto Alegre, RS (Brazil); Lequeux, Celine [Instituto de Quimica, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves 9500, 91501-970 Porto Alegre, RS (Brazil); Universite de Rennes 1, Rennes (France); 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 de Bahia, Salvador, BA (Brazil); Ferreira, Sergio L.C. [Instituto Nacional de Ciencia e Tecnologia do CNPq-INCT de Energia e Ambiente, Universidade Federal de Bahia, Salvador, BA (Brazil); Instituto de Quimica, Universidade Federal da Bahia, Salvador, Bahia 40170-290 (Brazil); Welz, Bernhard [Instituto Nacional de Ciencia e Tecnologia do CNPq-INCT de Energia e Ambiente, Universidade Federal de Bahia, Salvador, BA (Brazil); Departamento de Quimica, Universidade Federal de Santa Catarina, Florianopolis, SC (Brazil)

    2011-07-15

    The determination of cadmium (Cd) in fertilizers is of major interest, as this element can cause growth problems in plants, and also affect animals and humans. High-resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS GF AAS) with charge-coupled device (CCD) array detection overcomes several of the limitations encountered with conventional line source AAS, especially the problem of accurate background measurement and correction. In this work an analytical method has been developed to determine Cd in fertilizer samples by HR-CS GF AAS using slurry sampling. Both a mixture of 10 {mu}g Pd + 6 {mu}g Mg in solution and 400 {mu}g of iridium as permanent modifier have been investigated and aqueous standards were used for calibration. Pyrolysis and atomization temperatures were 600 {sup o}C and 1600 {sup o}C for the Pd-Mg modifier, and 500 deg. C and 1600 deg. C for Ir, respectively. The results obtained for Cd in the certified reference material NIST SRM 695 (Trace Elements in Multi-Nutrient Fertilizer) of 16.7 {+-} 1.3 {mu}g g{sup -1} and 16.4 {+-} 0.75 {mu}g g{sup -1} for the Pd-Mg and Ir modifier, respectively, were statistically not different from the certified value of 16.9 {+-} 0.2 {mu}g g{sup -1} on a 95% confidence level; however, the results obtained with the Ir modifier were significantly lower than those for the Pd-Mg modifier for most of the samples. The characteristic mass was 1.0 pg for the Pd-Mg modifier and 1.1 pg Cd for the Ir modifier, and the correlation coefficients (R{sup 2}) of the calibration were > 0.99. The instrumental limits of detection were 7.5 and 7.9 ng g{sup -1}, and the limits of quantification were 25 and 27 ng g{sup -1} for Pd-Mg and Ir, respectively, based on a sample mass of 5 mg. The cadmium concentration in the investigated samples was between 0.07 and 5.5 {mu}g g{sup -1} Cd, and hence below the maximum value of 20 {mu}g g{sup -1} Cd permitted by Brazilian legislation.

  18. Development of an analytical method for the determination of arsenic in gasoline samples by hydride generation-graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Becker, Emilene M. [Universidade Federal do Pampa, Bage, RS (Brazil); Universidade Federal de Pelotas, Pelotas, RS (Brazil); Dessuy, Morgana B.; Boschetti, Wiliam [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); Ferreira, Sergio L.C. [Instituto Nacional de Ciencia e Tecnologia do CNPq, INCT de Energia e Ambiente, Universidade Federal da Bahia, Salvador, BA (Brazil); Instituto de Quimica, Universidade Federal da Bahia, Salvador, BA (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)

    2012-05-15

    The purpose of the present work was to optimize the conditions for the determination of arsenic in gasoline with hydride generation-graphite furnace atomic absorption spectrometry after acid digestion using a full two-level factorial design with center point. The arsine was generated in a batch system and collected in a graphite tube coated with 150 {mu}g Ir as a permanent modifier. The sample volume, the pre-reduction conditions, the temperature program and modifier mass were kept fixed for all experiments. The estimated main effects were: reducing agent concentration (negative effect), acid concentration (negative effect) and trapping temperature (positive effect). It was observed that there were interactions between the variables. Moreover, the curvature was significant, indicating that the best conditions were at the center point. The optimized parameters for arsine generation were 2.7 mol L{sup -1} hydrochloric acid and 1.6% (w/v) sodium tetrahydroborate. The optimized conditions to collect arsine in the graphite furnace were a trapping temperature of 250 Degree-Sign C and a collection time of 30 s. The limit of detection was 6.4 ng L{sup -1} and the characteristic mass was 24 pg. Two different systems for acid digestion were used: a digester block with cold finger and a microwave oven. The concentration of arsenic found with the proposed method was compared with that obtained using a detergentless microemulsion and direct graphite furnace determination. The results showed that the factorial design is a simple tool that allowed establishing the appropriate conditions for sample preparation and also helped in evaluating the interaction between the factors investigated. - Highlights: Black-Right-Pointing-Pointer We determined As in gasoline using hydride generation-graphite furnace AAS. Black-Right-Pointing-Pointer We compared three sample preparation procedures. Black-Right-Pointing-Pointer A multivariate approach was used to optimize the conditions. Black

  19. 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.

  20. Development of rapid slurry methods for flame and direct current plasma emission and graphite furnace atomic absorption analysis of solid animal tissue

    Energy Technology Data Exchange (ETDEWEB)

    Fietkau, R.

    1986-01-01

    Studies are presented describing developments in the rapid, direct atomic spectrochemical analysis of meat samples by the technique of slurry atomization. The number of elements that can be determined in meat slurry samples has been increased and the concentration range that can be detected extended to included analysis at the part per billion as well as the percent level. Slurry atomization involves the rapid preparation procedure whereby the sample is simple homogenized with deionized distilled water prior to analysis. In this manner, rapid, quantitative analysis of hot dogs (processed meat) for dietary salt (Na, K) was achieved by premixed air-natural gas flame emission spectrometry. Quantitative analysis of mechanically separated meat for residual bone fragments (as Ca) was attained using a simple photometer when the premixed air-acetylene flame was used. The phosphate interference of the Ca emission signal was overcome by placing an insert in the spray chamber which decreased the droplet size of the aerosol reaching the flame. Slight matrix modification in the form of 2% nitric acid was necessary to solubilize the Ca from the bone fragments. Determining elements present at very low concentrations i.e. part per billion levels, in homogenized beef liver was evaluated using graphite furnace atomic absorption and shown to be viable for determinations of Pb, Cd, Cr, and Ni. Qualitative multielement analysis of several types of meat slurries by direct current plasma (DCP) emission spectrometry using both photographic and electronic modes of detection was reported for the first time.

  1. Preconcentration and determination of ultra-traces of platinum in human serum using the combined electrodeposition-electrothermal atomic absorption spectroscopy (ED-ETAAS) and chemometric method.

    Science.gov (United States)

    Najafi, Nahid Mashkouri; Shahparvizi, Shahram; Rafati, Hasan; Ghasemi, Ensieh; Alizadeh, Reza

    2010-09-21

    Platinum compounds, including cis-dichlorodiaminoplatinum(II) or cisplatin, are an important class of anti-cancer drugs, which should be carefully monitored in the biological fluids. In this study, electrodeposition coupled with electrothermal atomic absorption spectrometry (ETAAS) was used for determination of Pt concentration in the human serum samples. The chemometric techniques were also used to verify the probable interactions among the important and effective parameters in the atomization process. Using response surfaces obtained by two factorial design techniques, the experimental design was applied for three effective parameters namely ashing temperature, atomizing temperature and modifier concentration as effective parameters on the atomization of Pt. The in situ digestions of serum samples, as well as the separation of the ultra-traces of Pt from concomitant in these samples were performed by using the in situ electrodeposition (ED) technique prior to the measurement by ETAAS. Six plasma samples of a patient who was administered parenteral cisplatin were analyzed using the proposed ED-ETAAS technique. The results showed the pharmacokinetic parameters of cisplatin in serum in accordance to the well-established data. A relatively good reproducibility %RSD=2.44, low limit of detection LOD=2.54 microg/L and promising characteristic mass m(o)=91.30 pg were obtained using this technique.

  2. Comparison determinations of gold in ore between atomic absorption spectrophotometry and hydroquinone volumetric method%原子吸收分光光度法与氢醌容量法测定矿石中金的比对

    Institute of Scientific and Technical Information of China (English)

    李玲

    2013-01-01

    Two kinds of analysis methods of gold in the ores are compared. The results show that, the atomic absorption spectrophotometry is better than the hydroquinone volumetric method.%本文对矿石中金的两种分析方法进行了比对。结果表明原子吸收分光光度法要优于氢醌容量法。

  3. Development and validation of a general non-digestive method for the determination of palladium in bulk pharmaceutical chemicals and their synthetic intermediates by graphite furnace atomic absorption spectroscopy.

    Science.gov (United States)

    Wang, T; Walden, S; Egan, R

    1997-02-01

    A simple, selective, sensitive, accurate and relatively inexpensive method for the determination of palladium in bulk pharmaceutical chemicals (BPC) and their synthetic intermediates by graphite furnace atomic absorption spectroscopy has been developed and validated. Sample preparation by direct dissolution of sample in 70% nitric acid is simple and effective without adverse effects. The limit of detection and the limit of quantitation of the method were determined to be 0.7 ppm and 2 ppm respectively in BPC.

  4. Old and New Flavors of Flame (Furnace Atomic Absorption Spectrometry

    Directory of Open Access Journals (Sweden)

    Amália Geiza Gama Dionísio

    2011-01-01

    Full Text Available This paper presents some recent applications of Flame Atomic Absorption Spectrometry (FAAS to different matrices and samples. The time window selected was from 2006 up to March, 2011, and several aspects related to food, biological fluids, environmental, and technological samples analyses were reported and discussed. In addition, the chemometrics application for FAAS methods development was also taken into account, as well as the use of metal tube atomizers in air/acetylene flame. Preconcentration methods coupled to FAAS were discussed, and several approaches related to speciation, flotation, ionic liquids, among others were discussed. This paper can be interesting for researchers and FAAS users in order to see the state of the art of this technique.

  5. 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.

  6. 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.

  7. Evaluation of the effect of 16% carbamide peroxide gel (Nite White on mercury release from Iranian and foreign spherical and admixed amalgams by cold vapor atomic absorption method

    Directory of Open Access Journals (Sweden)

    Kasraie Sh.

    2008-04-01

    Full Text Available Background and Aim: Nowadays, esthetic dentistry has become an important part of modern dentistry. Bleaching is considered as a conservative, safe and effective way for treatment of discolored teeth. Although bleaching is commonly used on anterior teeth, the bleaching gel may come into contact with patient's former amalgam restorations and result in corrosive effects, dissolution of amalgam phases and increasing release of mercury. Mercury released from dental amalgam during mouthguard bleaching can be absorbed and increase the total mercury body burden. The aim of this study was to determine the amount of mercury released from Iranian and foreign brands of amalgams with spherical and admixed particles, polished and unpolished, after 16%carbamide peroxide gel application.Materials and Methods: This experimental in vitro study was performed on 256 Iranian and foreign amalgam samples with spherical and admixed particles. The provided samples were put in distilled water and classified according to the type of amalgam, shape of particles and quality of surface polishing. The test samples were placed in Nite White 16% carbamid peroxide gel and control samples were put in phosphate buffer (Ph=6.5 for 14 and 28 hours. The amount of released mercury was calculated using AVA-440 Mercury Analysis System (Thermo Jarrell Ash model SH/229 with cold-vapor atomic absorption. Data were analyzed using t-test, four way and three way ANOVA tests with P<0.05 as the level of significance.Results: 16% Nite White carbamide peroxide gel caused a significant increase in amount of mercury released from amalgams in all groups (P<0.05. Mercury release from Iranian amalgam was higher than that from the foreign brands (P<0.05. There was no significant difference in mercury released from spherical and admixed amalgams (P>0.05. The amount of mercury released from Iranian and foreign amalgams was time dependent (P<0.05. Furthermore, the amount of mercury released from

  8. 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.

  9. Determination of Lead in Blood by Atomic Absorption Spectrophotometry1

    Science.gov (United States)

    Selander, Stig; Cramér, Kim

    1968-01-01

    Lead in blood was determined by atomic absorption spectrophotometry, using a wet ashing procedure and a procedure in which the proteins were precipitated with trichloroacetic acid. In both methods the lead was extracted into isobutylmethylketone before measurement, using ammonium pyrrolidine dithiocarbamate as chelator. The simpler precipitation procedure was shown to give results identical with those obtained with the ashing technique. In addition, blood specimens were examined by the precipitation method and by spectral analysis, which method includes wet ashing of the samples, with good agreement. All analyses were done on blood samples from `normal' persons or from lead-exposed workers, and no additions of inorganic lead were made. The relatively simple protein precipitation technique gave accurate results and is suitable for the large-scale control of lead-exposed workers. PMID:5663425

  10. 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...

  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. Determination of Lead in Urine by Atomic Absorption Spectrophotometry1

    Science.gov (United States)

    Selander, Stig; Cramé, Kim

    1968-01-01

    A method for the determination of lead in urine by means of atomic absorption spectrophotometry (AAS) is described. A combination of wet ashing and extraction with ammonium pyrrolidine dithiocarbamate into isobutylmethylketone was used. The sensitivity was about 0·02 μg./ml. for 1% absorption, and the detection limit was about 0·02 μg./ml. with an instrumental setting convenient for routine analyses of urines. Using the scale expansion technique, the detection limit was below 0·01 μg./ml., but it was found easier to determine urinary lead concentrations below 0·05 μg./ml. by concentrating the lead in the organic solvent by increasing the volume of urine or decreasing that of the solvent. The method was applied to fresh urines, stored urines, and to urines, obtained during treatment with chelating agents, of patients with lead poisoning. Urines with added inorganic lead were not used. The results agreed well with those obtained with a colorimetric dithizone extraction method (r = 0·989). The AAS method is somewhat more simple and allows the determination of smaller lead concentrations. PMID:5647975

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 原子吸收光谱法测定重金属时的干扰因素及消除方法%Interference factors in testing heavy metal applied with atomic absorption spectrometry determination and eliminating methods

    Institute of Scientific and Technical Information of China (English)

    刘桂英

    2013-01-01

    The content of heavy metals in water is tested applied with the principle of atomic absorption spectrometry. The standard curve method is commonly used in flame atomic absorption spectrometry, which is a quantitative method and is the foundation for other analytical methods. So choosing the best environmental conditions as well as eliminating interference factors is very important for improving the accuracy of testing the heavy metal content. Interference factors in testing heavy metal applied with the calibration curve method and the eliminating methods are discussed.%水质中的重金属是基于原子吸收光谱分析的原理来测定的。常用的是火焰原子吸收光谱法中的标准曲线法,它是最基本的定量方法,也是其他分析方法的基础。所以选择分析环境的最佳条件,消除测定试样时的干扰因素,对提高测试试样中重金属含量的准确度至关重要。重点讨论原子吸收光谱分析中校准曲线法测定重金属时的干扰因素及消除方法。

  19. Comparison of serum calcium measurements with respect to five models of atomic absorption spectrometers using NBS-AACC calcium reference method and isotope-dilution mass spectrometry as the definitive method.

    Science.gov (United States)

    Copeland, B E; Grisley, D W; Casella, J; Bailey, H

    1976-10-01

    Utilizing the recently described reference method for calcium (NBS-AACC) and the recently developed definitive (referee) NBS method for serum calcium measurement by isotopedilution mass spectrometry (IDMS), an evaluation of five recent-model atomic absorption spectrometers was carried out. Under optimal conditions of instrument operation using aqueous standards, significant differences were found during the comparative analyses of three lyophilized pool samples and one liquid serum pool sample. Use of the NBS-AACC serum calcium protocol did not guarantee analytic results within +/- 2% of the IDMS value. In four of eight comparisons, differences from IDMS greater than 2% were observed. Several variables were studied to account for these differences. It was shown that a serum matrix, when present in standards used to bracket the unknown sample, reduced differences between instruments in four of four instances and improved the accuracy of the results from a range of -1.1 to +3.5% to +0.1 to +1.0%. It is concluded that a serum sample with a verified IDMS calcium value is a valuable tool that establishes an accurate and stable reference point for serum calcium measurement. The use of transfer-of-NBS-technology multipliers is suggested. Regional quality control serum pools and clinical chemistry survey sample materials that have been analyzed for calcium concentration by the NBS-IDMS definitive method are examples of these multipliers.

  20. Period Verification Method of Atomic Absorption Spectrophotometer and Application%原子吸收分光光度计的期间核查方法及应用

    Institute of Scientific and Technical Information of China (English)

    李淑琴

    2015-01-01

    The article describes the aims and methods of period verification for the atom absorption spectrophotometer.Cali-bration is carried out in accordance with the calibration specification, in order to ensure the credibility of instrument calibra-tion status.%文章阐述了原子吸收分光光度计期间核查的目的及方法,按仪器检定规程对仪器进行期间核查,以确保仪器校准状态的可信度。

  1. 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.

  2. 石墨炉原子吸收法测定萝卜中的硒%Graphite Furnace Atomic Absorption Method for the Determination of Selenium in Raphanus sativus L.

    Institute of Scientific and Technical Information of China (English)

    铁梅; 张莹; 张朝红; 惠秀娟; 陈忠林; 刘阳; 李宝瑞

    2013-01-01

    [Objective] Determination of selenium in Raphanus sativus L.by Graphite Furnace Atomic Absorption Spectrometry.[Method] Compared single ion(Cu,Ni,Pd) and mixing ion (Cu-Pd,Ni-Pd) by Graphite Furnace Atomic Absorption method for determination of selenium in improving action; To determine the optimal method for the determination of selenium by graphite furnace atomic absorption spectrometry by optimizing the lamp current,ashing temperature and atomization temperature,and determination of selenium in Raphanus sativus L..[Result] The result showed that 1 mg/ml Cu(NO3)2 as matrix modifier,ashing temperature and atomization temperature in 800 ℃,2 500 ℃ for optimum conditions of selenium content in Raphanus sativus L..The recovery rate was 99.6%-106.0%,relative standard deviation is 1.19%,the detection limit is 0.79 μg/L.[Conclusion] This method is simple,sensitive,stable,accurate,applicable to selenium determination in Raphanus sativus L..%[目的]建立石墨炉原子吸收法测定萝卜中硒的方法.[方法]比较了Cu、Ni、Pd及Cu-Pd、Ni-Pd协同作用对硒的测定的影响,确定最佳基改剂;通过优化灯电流、灰化温度和原子化温度等确定石墨炉原子吸收法测定硒的最佳方法,并测定萝卜中的硒.[结果]1mg/ml Cu(NO3)2作为基体改进剂,灰化温度800℃,原子化温度2 500℃为测定不同萝卜中硒的含量的适宜条件.在该条件下测定Se的加标回收率在99.6% ~ 106.0%,方法相对标准偏差为1.19%,检出限为0.79 μg/L.[结论]该方法简便、灵敏、稳定、准确,适用于萝卜中硒的分析测定.

  3. 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…

  4. 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…

  5. [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.

  6. 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.

  7. Determination of the Content of Zinc and Copper in Sewage Sludge by Microwave Digestion-atomic Absorption Method%微波消解-原子吸收法测定污泥中的铜、锌含量

    Institute of Scientific and Technical Information of China (English)

    任旭锋; 王长智; 李娇英

    2015-01-01

    参考环境标准》固体废物镍铜的测定》和》固体废物铅锌隔的测定》优化了原子吸收仪工作参数和微波消解条件,建立了微波消解-原子吸收法测定太阳能电池行业废水处理后污泥中的铜和锌元素的分析方法,方法的检出限范围为0.001~0.009 mg/L,方法加标回收率93.3%~109%,相对标准偏差RSD均小于5%。%An analysis method as microwave digestion-atomic absorption spectroscopy ( ADAAS) was established for the determination of copper and zinc in the sludge from the treatment of solar cell industry wastewater.With reference to the environmental standards of Determination of Nickel and Copper Solid Waste and Determination of Lead, Zinc and Cadmium Solid Waste, the microwave digestion conditions as well as the operating parameters of atomic absorption spectrometer were optimized.The detection limit of this method was in the range of 0.001 ~0.009 mg/L.The relative standard deviation ( RSD) was less than 5%and recoveries were 93.3%~109.0%.

  8. Comparison of liposome entrapment parameters by optical and atomic absorption spectrophotometry.

    Science.gov (United States)

    Yoss, N L; Popescu, O; Pop, V I; Porutiu, D; Kummerow, F A; Benga, G

    1985-01-01

    Methods for the complete characterization of liposomes prepared by ether-injection are described in detail. The validity of atomic absorption spectrophotometry for measuring markers of trapped volume was checked by comparative determinations of markers with established optical spectrophotometrical methods. The favorable results using atomic absorption spectrophotometry to quantitate the marker Mn2+ are of particular relevance as manganese ion is also the paramagnetic probe in n.m.r. measurements of water permeability of liposomes; our results indicate that in such measurements no other marker need be incorporated.

  9. 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...

  10. Determination of platinum, palladium, and lead in biological samples by atomic absorption spectrophotometry.

    Science.gov (United States)

    Tillery, J B; Johnson, D E

    1975-01-01

    A flameless atomic absorption method for the coextraction of platinum and palladium from biological and environmental samples by high molecular weight amine (HMWA) is given. Also, methods for lead determination in biological samples by use of extraction flameless analysis and direct aspiration-flame analysis are reported. A study of lead contamination of Vacutainer tubes is given. PMID:1227857

  11. 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...

  12. Fast emulsion-based method for simultaneous determination of Co, Cu, Pb and Se in crude oil, gasoline and diesel by graphite furnace atomic absorption spectrometry.

    Science.gov (United States)

    Luz, Maciel S; Nascimento, Angerson N; Oliveira, Pedro V

    2013-10-15

    A method for the simultaneous determination of Co, Cu, Pb and Se in crude oil, gasoline and diesel samples using emulsion-based sampling and GF AAS is proposed. 400mg of sample was weighted in volumetric flask following the sequential addition of 125 µL of hexane and 7.5 mL of Triton X-100(®) (20% mv(-1)). Subsequently, the mixture was stirred in ultrasonic bath, during 30 min, before dilution to 25 mL with deionized water. Aliquots of 20 μL of reference solution or sample emulsion were co-injected into the graphite tube with 10 μL of 2 g L(-1) Pd(NO3)2. The pyrolysis and atomization temperatures were 1300°C and 2250°C, respectively. The limits of detection (n=10, 3σ) and characteristic masses were 0.02 μg g(-1) (0.32 μg L(-1)) and 18 pg for Co, 0.03 μg g(-1) (0.48 μg L(-1)) and 15 pg for Cu, 0.04 μg g(-1) (0.64 μg L(-1)) and 48 pg for Pb, and 0.11 μg g(-1) (1.76 μg L(-1)) and 47 pg for Se. The reliabilities of the proposed method for Co and Se were checked by SRM(®) 1634c Residual Oil analysis. The found values are in accordance to the SRM at 95% confidence level (Student's t-test). Each sample was spiked with 0.18 μg g(-1) of Co, Cu, Pb and Se and the recoveries varied from 92% to 116% for Co, 83% to 117% for Cu, 72% to 117% for Pb, and 82% to 122% for Se.

  13. Micro determination of plasma and erythrocyte copper by atomic absorption spectrophotometry

    Science.gov (United States)

    Blomfield, Jeanette; Macmahon, R. A.

    1969-01-01

    The free and total plasma copper and total erythrocyte copper levels have been determined by simple, yet sensitive and highly specific methods, using atomic absorption spectrophotometry. For total copper determination, the copper was split from its protein combination in plasma or red cells by the action of hydrochloric acid at room temperature. The liberated copper was chelated by ammonium pyrrolidine dithiocarbamate and extracted into n-butyl acetate by shaking and the organic extract was aspirated into the atomic absorption spectrophotometer flame. The entire procedure was carried out in polypropylene centrifuge tubes, capped during shaking. For the free plasma copper measurement the hydrochloric acid step was omitted. Removal of the plasma or erythrocyte proteins was found to be unnecessary, and, in addition, the presence of trichloracetic acid caused an appreciable lowering of absorption. Using a double-beam atomic absorption spectrophotometer and scale expansion × 10, micro methods have been derived for determining the total copper of plasma or erythrocytes with 0·1 ml of sample, and the free copper of plasma with 0·5 ml. The macro plasma copper method requires 2 ml of plasma and is suitable for use with single-beam atomic absorption spectrophotometers. With blood from 50 blood donors, normal ranges of plasma and erythrocyte copper have been determined. PMID:5776543

  14. 火焰原子吸收法快速测定低钠盐中的钾含量%Rapid Determination of the Content of Potassium in Low Sodium Salt with Flame Atomic Absorption Method

    Institute of Scientific and Technical Information of China (English)

    刘长军; 李建伟; 吴鸣

    2015-01-01

    低钠盐中的钾是重要的指标之一,应用火焰原子吸收法,使用硝酸铯作为消电离剂,能够在404.4nm灵敏线能够快速准确的测定低钠盐中的常量钾。结果表明该方法重现性好、灵敏度高、简便快速。%K+ is an important indicator of low sodium salt. Using flame atomic absorption method and taking cesium nitrate as deionization agent , we can determine potassium content in low sodium salt in 404.4nm sensitive line rapidly and accurately. The results show that the method has good reproducibility, high sensitivity, simple and rapid.

  15. Working towards accreditation by the International Standards Organization 15189 Standard: how to validate an in-house developed method an example of lead determination in whole blood by electrothermal atomic absorption spectrometry.

    Science.gov (United States)

    Garcia Hejl, Carine; Ramirez, Jose Manuel; Vest, Philippe; Chianea, Denis; Renard, Christophe

    2014-09-01

    Laboratories working towards accreditation by the International Standards Organization (ISO) 15189 standard are required to demonstrate the validity of their analytical methods. The different guidelines set by various accreditation organizations make it difficult to provide objective evidence that an in-house method is fit for the intended purpose. Besides, the required performance characteristics tests and acceptance criteria are not always detailed. The laboratory must choose the most suitable validation protocol and set the acceptance criteria. Therefore, we propose a validation protocol to evaluate the performance of an in-house method. As an example, we validated the process for the detection and quantification of lead in whole blood by electrothermal absorption spectrometry. The fundamental parameters tested were, selectivity, calibration model, precision, accuracy (and uncertainty of measurement), contamination, stability of the sample, reference interval, and analytical interference. We have developed a protocol that has been applied successfully to quantify lead in whole blood by electrothermal atomic absorption spectrometry (ETAAS). In particular, our method is selective, linear, accurate, and precise, making it suitable for use in routine diagnostics.

  16. 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.

  17. 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...

  18. 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.

  19. Determination of Palladium in Resin by Lead Fire Assaying-Flame Atomic Absorption Spectrometric Method%铅试金富集-火焰原子吸收光谱法测定树脂中钯

    Institute of Scientific and Technical Information of China (English)

    王芳; 陈小兰; 林海山; 李小玲; 肖红新

    2013-01-01

    通过铅试金富集树脂中的钯并用银作钯灰吹保护,得到的银钯合粒用王水溶解,在5%的盐酸介质中,采用原子吸收光谱法测定钯,该法测钯的相对标准偏差RSD为0.53%,加标回收率在99.04%~100.10%之间。%Palladium in resin was enriched by lead assaying, using silver as a protective agent to produce silver-palladium alloy, and then the alloy was dissolved in aqua regia. Air acetylene flame atomic absorption spectrometric method was used to determinate palladium in 5%hydrochloric acid solution. The relative standard deviation (RSD) in determination of palladium is 0.53%and the recovery rate is between 99.04%~100.10%.

  20. 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.

  1. 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.

  2. Quantitative Determination of Arsenic in Bottled Drinking Water Using Atomic Absorption Spectroscopy

    Directory of Open Access Journals (Sweden)

    Maria Guţu Claudia

    2013-10-01

    Full Text Available Background: Many studies have been performed in the past few years, to determine arsenic speciation in drinking water, food chain and environment, arsenic being a well-recognized carcinogenic and toxic agent mainly in its inorganic species. The instrumental techniques used for arsenic determination, such as hydride generation atomic absorption spectrometry (HGAAS, graphite furnace atomic absorption spectrometry (GFAAS and inductively coupled plasma mass spectrometry (ICP-MS, can provide a great sensitivity only on the total amount. Objective: The aim of this study was to develop a simple and rapid method and to analyze the concentration of total inorganic arsenic in bottled drinking water. Methods: Total arsenic was determined in samples from six different types of commercially available bottled drinking water using atomic absorption spectrometry with electrothermal or hydride generation vaporisation. All drinking water samples were acidified with 0.1M nitric acid to match the acidity of the standards. Results: The method was linear within the studied range (1-5 μg/L, R = 0.9943. The quantification limits for arsenic determination were 0.48 μg/L (HGAAS and 0.03 μg/L (GFAAS. The evaluated arsenic content in drinking water was within the accepted limits provided by law. Conclusions: A simple and sensitive method for the quantification of arsenic in drinking water using atomic absorbtion spectroscopy was described, which can be further used in toxicological studies. As an additional advantage, the system is very fast, efficient and environmental friendly

  3. 石墨炉原子吸收分光光度法直接测定全血中锗%Graphite furnace atomic absorption spectrophotometric method for the direct determination of germanium in blood

    Institute of Scientific and Technical Information of China (English)

    高丽红

    2012-01-01

    Objective:To establish a graphite furnace atomic absorption spectrophotometric method for the determination of germanium in whole blood. Methods: Without treatment, germanium content in the sample was directly determined by graphite furnace atomic absorption spectrophotometry after sample dilution with 0. l%TritonX -100/ 0.2% HNO3 (v/v) as diluent and 0. 5 mg/ml calcium nitrate as matrix modifier. Results: The detection limit of the method (re = 10) was 0. 75 mg/L, the linearity was observed in the range of 0 μg/L ~ 190 μg/L, the relative standard deviation was 0. 8% ~ 3. 2% , the recovery rate was 99. 5% ~ 103. 6% . Conclusion: The method is simple, rapid with high recovery rate and precision, it is applicable to the determination of germanium content in whole blood.%目的:建立石墨炉原子吸收分光光度法测定全血中锗的方法.方法:样品无需处理,以0.1%TritonX-100/0.2% HNO3(v/v)为稀释液,以0.5 mg/ml硝酸钙为基体改进剂,对血液适当稀释后,直接用石墨炉原子吸收分光光度法测定锗的含量.结果:方法最低检出限(n=10)为0.75 mg/L,线性范围为0μg/L~190 μg/L,相对标准偏差0.8% ~3.2%,回收率为99.5% ~ 103.6%.结论:方法具有简便、快速、回收率高、精密度高的优点,适用于全血中锗含量的测定.

  4. 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.

  5. A single-reagent method for the speciation of chromium in natural waters by flame atomic absorption spectrometry based on vesicular liquid coacervate extraction

    Science.gov (United States)

    Tsogas, George Z.; Giokas, Dimosthenis L.; Vlessidis, Athanasios G.; Evmiridis, Nicholaos P.

    2004-07-01

    The concept of liquid coacervate extraction (LCE) is deployed to accomplish metal speciation after appropriate derivatization of the target metallic species. The method involves the partitioning of the hydrophobic metal chelates, produced from the reaction of Cr with APDC, in the vesicular aggregates formed from an anionic surfactant with alkaline earth metals and a cosurfactant, which are separated from the bulk aqueous phase. Under the established experimental conditions, the method offers high reproducibility, very low detection limits and recoveries in the range of 95-104%. Moreover, the method affords high tolerance for EDTA, which is used as a masking agent in order to avoid interferences from co-extracted metals. Validation of the outlined method was performed by analysing a certified reference material (BCR 544) yielding recoveries higher than 94% for both Cr oxidation states.

  6. A single-reagent method for the speciation of chromium in natural waters by flame atomic absorption spectrometry based on vesicular liquid coacervate extraction

    Energy Technology Data Exchange (ETDEWEB)

    Tsogas, George Z.; Giokas, Dimosthenis L. E-mail: dgiokas@cc.uoi.gr; Vlessidis, Athanasios G.; Evmiridis, Nicholaos P

    2004-07-30

    The concept of liquid coacervate extraction (LCE) is deployed to accomplish metal speciation after appropriate derivatization of the target metallic species. The method involves the partitioning of the hydrophobic metal chelates, produced from the reaction of Cr with APDC, in the vesicular aggregates formed from an anionic surfactant with alkaline earth metals and a cosurfactant, which are separated from the bulk aqueous phase. Under the established experimental conditions, the method offers high reproducibility, very low detection limits and recoveries in the range of 95-104%. Moreover, the method affords high tolerance for EDTA, which is used as a masking agent in order to avoid interferences from co-extracted metals. Validation of the outlined method was performed by analysing a certified reference material (BCR 544) yielding recoveries higher than 94% for both Cr oxidation states.

  7. 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.

  8. 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.

  9. Analysis of Mercurial Preservatives in Bacterins, Vaccines, and Antisera by Atomic Absorption Spectrophotometry

    Science.gov (United States)

    Woodward, Paul W.; Pemberton, John R.

    1974-01-01

    A flameless atomic absorption method was developed for the determination of mercurial preservatives in biologicals. The assay was based on a quantitative determination of the mercury content of these preservatives. This method was used to analyze a variety of samples and yielded reproducible results with satisfactory recoveries. The procedure is presented in a simplified block diagram and described in detail relating its suitability for routine assay of large numbers of samples. PMID:4833363

  10. Improved extraction method for the determination of iron, copper, and nickel in new varieties of sunflower oil by atomic absorption spectroscopy.

    Science.gov (United States)

    Ansari, Rehana; Kazi, Tasneem G; Jamali, Mohammad K; Arain, Mohammad B; Sherazi, Syed T; Jalbani, Nusrat; Afridi, Hassan I

    2008-01-01

    A simple and fast procedure is proposed for the extraction of iron (Fe), copper (Cu), and nickel (Ni) in 16 varieties of sunflower seed oil samples using an ultrasonic bath. The experimental parameters of the ultrasonic-assisted extraction (UAE) method were optimized to improve the sensitivity and detect the metals at trace levels in minimum time. Conventional wet acid digestion method was used for comparative purposes. The optimum recovery of all 3 metals was obtained by UAE for 7 min, while the separation of aqueous and organic phases after extraction using centrifugation (UAE-2) required 3 min, as compared to the conventional equilibration method (UAE-1) that required 90 min. The respective recoveries of Cu, Fe, and Ni obtained with UAE-2 were in the range of 95.8-97.5, 93.5-98.3, and 95.6-98.2%, respectively, for different varieties of sunflower oil samples. Accuracy was determined by the standard addition method. Under the optimum operating conditions, the limits of detection obtained from the standard addition curves were 21.7, 20.4, and 35.6 ng/mL for Fe, Cu, and Ni, respectively. The fact that all varieties of sunflower oil contain significant amounts of Fe, Cu, and Ni indicates the deterioration of sunflower oil quality immediately after extraction from seeds, which poses a threat to oil quality and human health.

  11. A rapid fire-assay/atomic-absorption method for the determination of platinum, palladium and gold in ores and concentrates: A modification of the tin-collection scheme.

    Science.gov (United States)

    Moloughney, P E; Faye, G H

    1976-05-01

    The tin-collection scheme of fire-assaying has been simplified to permit the rapid and accurate determination of platinum, palladium and gold in ores and related materials. The presence of tellurium in the charge ensures that the precious metals remain insoluble during the parting of the tin button with hydrochloric acid. The residue is easily collected and dissolved and the resultant solution analysed for the precious metals by AAS. The accuracy of the method has been established by application to five diverse certified reference materials.

  12. A novel method for the determination of trace copper in cereals by dispersive liquid-liquid microextraction based on solidification of floating organic drop coupled with flame atomic absorption spectrometry

    Institute of Scientific and Technical Information of China (English)

    Chun Xia Wu; Qiu Hua Wu; Chun Wang; Zhi Wang

    2011-01-01

    A novel, simple, rapid, efficient and environment-friendly method for the determination of trace copper in cereal samples was developed by using dispersive liquid-liquid microextraction based on solidification of floating organic drop (DLLME-SFO) followed by flame atomic absorption spectrometry. In the DLLME-SFO, copper was complexed with 8-hydroxy quinoline and extracted into a small volume of 1-dodecanol, which is of low density, low toxicity and proper melting point near room temperature. The experimental parameters affecting the extraction efficiency were investigated and optimized. Under the optimum conditions, the calibration graph exhibited linearity over the range of 0.5-500 ng/mL with the correlation coefficient (r) of 0.9996. The enrichment factor was 122 and the limit of detection was 0.1 ng/mL. The method was applied to the determination of copper in the complex matrix samples such as rice and millet with the recoveries for the spiked samples at 5.0 and 10.0 μg/g falling in the range of 92.0-98.0% and the relative standard deviation of 3.9-5.7%.

  13. Reliability of graphite furnace atomic absorption spectrometry as ...

    African Journals Online (AJOL)

    reducing the interference problems by various techniques [12]. ... Slit (nm). 0.7. 0.7. Lamp type. EDL. EDL. Pyrolysis temp/Atomization temp. (oC). 1200/2000. 900 ..... AOAC Guidelines for Single-Laboratory Validation of. Chemical Methods for ...

  14. 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.

  15. 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

  16. Development of a new green non-dispersive ionic liquid microextraction method in a narrow glass column for determination of cadmium prior to couple with graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Naeemullah, E-mail: naeemullah433@yahoo.com [Gaziosmanpaşa University, Faculty of Science and Arts, Chemistry Department, 60250 Tokat (Turkey); National Centre of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan); Kazi, Tasneem Gul [National Centre of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan); Tuzen, Mustafa [Gaziosmanpaşa University, Faculty of Science and Arts, Chemistry Department, 60250 Tokat (Turkey); Shah, Faheem; Afridi, Hassan Imran [National Centre of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan); Citak, Demirhan [Gaziosmanpaşa University, Faculty of Science and Arts, Chemistry Department, 60250 Tokat (Turkey)

    2014-02-17

    Graphical abstract: -- Highlights: •A novel and rapid non-dispersive ionic liquid based microextractions. •We used a long narrow glass column to provide more contact area between two media (aqueous and extractive). •APDC using as complexing agent and analyzed by GFAAS. •Introduced a novel approach that reduced solvent consumption, effort, time. •It was applied for determination of understudy analytes in real water sample. -- Abstract: Easy and innovative non-dispersive ionic liquid based microextraction (NDILME) has been developed for preconcentration of trace level of cadmium (Cd) in aqueous real surface water samples prior to couple with graphite furnace atomic absorption spectrometry (GFAAS). A 200 cm long narrow glass column containing aqueous solution of standard/sample was used to increase phase transfer ratio by providing more contact area between two medium (aqueous and extractive), which drastically improve the recoveries of labile hydrophobic chelate of Cd ammonium pyrrolidinedithiocarbamate (APDC), into ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate [C{sub 4}mim][PF{sub 6}]. Different aspect of the desire method have been investigated and optimized. Under the optimized key experimental variables, limit of detection (LOD) and enhancement factor (EF) were achieved to be 0.5 ng L{sup −1} and 150, respectively. Reliability of the model method was checked by relative standard deviation (%RSD), which was found to be < 5%. Validity and accuracy of the developed method was checked by analysis of certified reference water samples (SLRS-4 Riverine water) using standard addition method. Application of the model method was productively performed by analysis of Cd in real surface water samples (tap and sea)

  17. Method of trivalent chromium concentration determination by atomic spectrometry

    Science.gov (United States)

    Reheulishvili, Aleksandre N [Tbilisi, 0183, GE; Tsibakhashvili, Neli Ya [Tbilisi, 0101, GE

    2006-12-12

    A method is disclosed for determining the concentration of trivalent chromium Cr(III) in a sample. The addition of perchloric acid has been found to increase the atomic chromium spectrometric signal due to Cr(III), while leaving the signal due to hexavalent chromium Cr(VI) unchanged. This enables determination of the Cr(III) concentration without pre-concentration or pre-separation from chromium of other valences. The Cr(III) concentration may be measured using atomic absorption spectrometry, atomic emission spectrometry or atomic fluorescence spectrometry.

  18. 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.

  19. 原子吸收光度法分析临沧饮用水中钙、镁元素%Analysis of Calcium and Magnesium of Drinking Water in Lincang by Atomic Absorption Photometry Method

    Institute of Scientific and Technical Information of China (English)

    阳小勇; 徐运贵

    2016-01-01

    分析云南省临沧农村地区饮用水的钙、镁离子浓度.在选定的最佳实验条件下采取火焰原子吸收法.所得钙镁离子的线性回归方程分别为Y=0.0659x+0.0403(R2=0.9965), Y=0.1242x+0.0014(R2=0.9981);钙、镁离子的加标回收率分别在97.1%~103.6%,95.3%~101.4%之间。结果表明:该地区饮用水的钙、镁元素最高浓度为160 mg/kg,属于软水。%The concentration of calcium and magnesium ion of drinking in rural areas of Lincang was analyzed. Flame atomic absorption spectroscopy method was used under best experimental condition. The equation of linear regression was as follows: Ca: Y=0. 0659x+0. 0403 (R2=0. 9965), Mg: Y=0. 1242x+0. 0014 (R2=0. 9981). The recoveries of standard addition were as follows:Ca:97. 1% ~103. 6%, Mg:95. 3% ~101. 4%. The results showed that the highest concentration of calcium and magnesium of drinking water in rural areas of Lincang were 160 mg/kg. The water belonged to soft water.

  20. 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).

  1. 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.

  2. 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.

  3. 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.

  4. Determination of antimony in concentrates, ores and non-ferrous materials by atomic-absorption spectrophotometry after iron-lanthanum collection, or by the iodide method after further xanthate extraction.

    Science.gov (United States)

    Donaldson, E M

    1979-11-01

    Methods for determining trace and moderate amounts of antimony in copper, nickel, molybdenum, lead and zinc concentrates and in ores are described. Following sample decomposition, antimony is oxidized to antimony(V) with aqua regia, then reduced to antimony(III) with sodium metabisulphite in 6M hydrochloric acid medium and separated from most of the matrix elements by co-precipitation with hydrous ferric and lanthanum oxides. Antimony (>/= 100 mug/g) can subsequently be determined by atomic-absorption spectrophotometry, at 217.6 nm after dissolution of the precipitate in 3M hydrochloric acid. Alternatively, for the determination of antimony at levels of 1 mug/g or more, the precipitate is dissolved in 5M hydrochloric acid containing stannous chloride as a reluctant for iron(III) and thiourea as a complexing agent for copper. Then tin is complexed with hydrofluoric acid, and antimony is separated from iron, tin, lead and other co-precipitated elements, including lanthanum, by chloroform extraction of its xanthate. It is then determined spectrophotometrically, at 331 or 425 nm as the iodide. Interference from co-extracted bismuth is eliminated by washing the extract with hydrochloric acid of the same acid concentration as the medium used for extraction. Interference from co-extracted molybdenum, which causes high results at 331 nm, is avoided by measuring the absorbance at 425 nm. The proposed methods are also applicable to high-purity copper metal and copper- and lead-base alloys. In the spectrophotometric iodide method, the importance of the preliminary oxidation of all of the antimony to antimony(V), to avoid the formation of an unreactive species, is shown.

  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. 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.

  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. 氘灯对原子吸收法测定高盐废水中镉含量的影响%Effect of Deuterium Lamp on the Determination of Cadmium Content in High Salt Wastewater Adopting Atomic Absorption Method

    Institute of Scientific and Technical Information of China (English)

    周婷; 王德龙; 汪廷洪; 李科

    2011-01-01

    In petrochemical industry, the gas production wastewater usually contains high content of salt. It will disturb the determination of heavy metals resulting in a deviate from the real value if the determination adopting the method for ground water and surface water. In this paper, a novel determination method for cadmium was developed by adopting the Atomic Absorption Spectrometry to subtract the background through using the deuterium lamp, which was suitable to determine the cadmium content in high salt wastewater. Experiments confirmed that the relative error was less than 8.75% and the detection limit was 0. 0042 mg/L with recovery of 93. 8% -101%. The repeatability was high enough to meet the requirement of determination.%在石化行业中,由于采气废水多为高舍盐废水,如果按照地表水、地下水的测试方法对其重金属指标进行测试,其测试结果和真实值之间存在较大的偏差。本研究中采用火焰原子吸收法对影响吸收的背景进行氘灯扣除,得到了一种适合于高含盐废水体中镉含量测定的分析方法。通过实验验证,该方法相对误差在8.75%以内,检测限0.0042mg/L,回收率在93.8%-101%之间,并且重现性良好,能够满足分析测试的要求。

  9. 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.

  10. 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.

  11. 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

  12. 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.

  13. Highly selective micro-sequential injection lab-on-valve (μSI-LOV) method for determination of ultra trace concentrations of nickel in saline matrices using detection by electrothermal atomic absorption spectrometr

    DEFF Research Database (Denmark)

    Long, Xiangbao; Miró, Manuel; Jensen, Rikard

    2006-01-01

    A highly selective procedure is proposed for the determination of ultra trace level concentrations of nickel in saline aqueous matrices exploiting a micro sequential injection lab-on-salve (μSI-LOV) sample pretreatment protocol comprising bead injection separation/pre-concentration and detection...... by electrothermal atomic absorption spectrometry (ETAAS). Based on the dimethylglyoxime (DMG) gravimetric procedure used for nickel analysis, the sample, as contained in pH 9.0 buffer, is, after on-line merging with the chelating reagent, transported to a reaction coil attached to one of the external ports...

  14. 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

  15. 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)

  16. 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).

  17. 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.)

  18. 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.

  19. 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).

  20. Determination of Cd,Cu,Pb,Fe,Zn in Bottled Drinking Water through Atomic Absorption Spectrometry Method%原子吸收光谱法对瓶装饮用水中Cd、Cu、Pb、Fe、Zn的分析

    Institute of Scientific and Technical Information of China (English)

    李帅; 沈祥森; 李勇

    2011-01-01

    10 different brands of commercial bottled drinking water for the experimental materials,using graphite furnace atomic absorption and flame atomic absorption spectrometry,the bottled water Cd、Cu、Pb、Fe、Zn five heavy metals were determined to understand the different brand bottled drinking water content of the five heavy metals.The results showed that:The whole bottled water content of the five heavy metals Cd、Cu、Pb、Fe、Zn are up to national standard requirements.%以10种不同品牌的市售瓶装饮用水为研究对象,运用石墨炉原子吸收法和火焰原子吸收法对其Cd、Cu、Pb、Fe、Zn5种重金属元素的含量进行分析,以了解不同品牌的瓶装饮用水中重金属元素的含量情况。研究结果表明:10种市售瓶装饮用水中的Cd、Cu、Pb、Fe、Zn 5种重金属含量均达到国标要求。

  1. 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.

  2. Plasmon absorption modulator systems and methods

    Science.gov (United States)

    Kekatpure, Rohan Deodatta; Davids, Paul

    2014-07-15

    Plasmon absorption modulator systems and methods are disclosed. A plasmon absorption modulator system includes a semiconductor substrate, a plurality of quantum well layers stacked on a top surface of the semiconductor substrate, and a metal layer formed on a top surface of the stack of quantum well layers. A method for modulating plasmonic current includes enabling propagation of the plasmonic current along a metal layer, and applying a voltage across the stack of quantum well layers to cause absorption of a portion of energy of the plasmonic current by the stack of quantum well layers. A metamaterial switching system includes a semiconductor substrate, a plurality of quantum well layers stacked on a top surface of the semiconductor substrate, and at least one metamaterial structure formed on a top surface of the stack of quantum well layers.

  3. 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.

  4. [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.

  5. 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.

  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. Estimation of calcium and magnesium in serum and urine by atomic absorption spectrophotometry

    Science.gov (United States)

    Thin, Christian G.; Thomson, Patricia A.

    1967-01-01

    A method has been described for the estimation of calcium and magnesium in serum and urine using atomic absorption spectrophotometry. The precision and accuracy of the techniques have been determined and were found to be acceptable. The range of values for calcium and magnesium in the sera of normal adults was found to be: serum calcium (corrected to a specific gravity of 1·026) 8·38-10·08 mg. per 100 ml.; serum magnesium 1·83-2·43 mg. per 100 ml. PMID:5602562

  8. 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.

  9. 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…

  10. 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.

  11. 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…

  12. 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.

  13. 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.

  14. 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...

  15. 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.

  16. 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.

  17. 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.

  18. Iodine absorption cells quality evaluation methods

    Science.gov (United States)

    Hrabina, Jan; Zucco, Massimo; Holá, Miroslava; Šarbort, Martin; Acef, Ouali; Du-Burck, Frédéric; Lazar, Josef; Číp, Ondřej

    2016-12-01

    The absorption cells represent an unique tool for the laser frequency stabilization. They serve as irreplaceable optical frequency references in realization of high-stable laser standards and laser sources for different brands of optical measurements, including the most precise frequency and dimensional measurement systems. One of the most often used absorption media covering visible and near IR spectral range is molecular iodine. It offers rich atlas of very strong and narrow spectral transitions which allow realization of laser systems with ultimate frequency stabilities in or below 10-14 order level. One of the most often disccussed disadvantage of the iodine cells is iodine's corrosivity and sensitivity to presence of foreign substances. The impurities react with absorption media and cause spectral shifts of absorption spectra, spectral broadening of the transitions and decrease achievable signal-to-noise ratio of the detected spectra. All of these unwanted effects directly influence frequency stability of the realized laser standard and due to this fact, the quality of iodine cells must be precisely controlled. We present a comparison of traditionally used method of laser induced fluorescence (LIF) with novel technique based on hyperfine transitions linewidths measurement. The results summarize advantages and drawbacks of these techniques and give a recommendation for their practical usage.

  19. 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.

  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. 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.

  2. 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.

  3. 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.

  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 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.

  6. 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.

  7. [Studies on cold resistance of hazel determined and analyzed by atomic absorption spectrometry].

    Science.gov (United States)

    Li, Xiu-Xia; Liu, Cheng-Cai; Zhang, Wei-Dong; Shao, Hong; Wu, Heng-Mei; Wang, Zhong; Yang, Yong-Nian; Li, Ji-Lin

    2010-06-01

    Using annual branch of hazel as the experimental materials, the K(+)-leakage and relative electric conductivity of three hazel species (six hazel clones) which had been treated with different low temperature were determined by electro-conductivity gauge and atomic absorption spectrometry. Regression models were established for low temperature to the K(+)-leakage or the relative electric conductivity of six hazel clones. The results showed that there was the same result of cold resistance for all clones using the two methods of comprehensive evaluation, and the indicator of K(+)-leakage rate determined by atomic absorption spectrometry can be used as a means of early identification of cold resistance of hazel clones. There were obvious differences among the clones in the ability of cold resistance. The order of the ability of cold resistance for the six hazel clones was C7R7 > Z-9-40 > C6R1 > CS2R1 > Z-9-22 > Z-9-30, and the order of the ability of cold resistance for the three hazel species was C. heterophylla > C. heterophyllax X (C. heterophylla X C. avellana) > C. heterophylla X C. avellana. The median lethal temperature of tissue for all clones is -26(-)-40 degrees "C.

  8. 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

  9. 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.

  10. 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.

  11. 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.

  12. 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)%.

  13. 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.

  14. 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.

  15. Handling complex effects in slurry-sampling-electrothermal atomic absorption spectrometry by multivariate calibration

    Energy Technology Data Exchange (ETDEWEB)

    Felipe-Sotelo, M. [Dept. Analytical Chemistry. University of A Coruna, Campus da Zapateira s/n, E-15071 A Coruna (Spain); Cal-Prieto, M.J. [Dept. Analytical Chemistry. University of A Coruna, Campus da Zapateira s/n, E-15071 A Coruna (Spain); Gomez-Carracedo, M.P. [Dept. Analytical Chemistry. University of A Coruna, Campus da Zapateira s/n, E-15071 A Coruna (Spain); Andrade, J.M. [Dept. Analytical Chemistry. University of A Coruna, Campus da Zapateira s/n, E-15071 A Coruna (Spain)]. E-mail: andrade@udc.es; Carlosena, A. [Dept. Analytical Chemistry. University of A Coruna, Campus da Zapateira s/n, E-15071 A Coruna (Spain); Prada, D. [Dept. Analytical Chemistry. University of A Coruna, Campus da Zapateira s/n, E-15071 A Coruna (Spain)

    2006-07-07

    Analysis of solid samples by slurry-sampling-electrothermal atomic absorption spectrometry (SS-ETAAS) can imply spectral and chemical interferences caused by the large amount of concomitants introduced into the graphite furnace. Sometimes they cannot be solved using stabilized temperature platform furnace (STPF) conditions or typical approaches (previous sample ashing, use of chemical modifiers, etc.), which are time consuming and quite expensive. A new approach to handle interferences using multivariate calibrations (partial least squares, PLS, and artificial neural networks, ANN) is presented and exemplified with a real problem consisting on determining Sb in several solid matrices (soils, sediments and coal fly ash) as slurries by ETAAS. Experimental designs were implemented at different levels of Sb to develop the calibration matrix and assess which concomitants (seven ions were considered) modified the atomic signal mostly. They were Na{sup +} and Ca{sup 2+} and they induced simultaneous displacement, depletion (enhancement) and broadening of the atomic peak. Here it is shown that these complex effects can be handled in a reliable, fast and cost-effective way to predict the concentration of Sb in slurry samples of several solid matrices. The method was validated predicting the concentrations of five certified reference materials (CRMs) and studying its robustness to current ETAAS problems. It is also shown that linear PLS can handle eventual non-linearities and that its results are comparable to more complex (non-linear) models, as those from ANNs.

  16. 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.

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. Flow Injection and Atomic Absorption Spectrometry (FI-AAS) -

    DEFF Research Database (Denmark)

    Hansen, Elo Harald

    1996-01-01

    One of the advantages of the flow injection (FI) concept is that it is compatible with virtually all detection techniques. Being a versatile vehicle for enhancing the performance of the individual detection devices, the most spectacular results have possibly been obtained in conjunction with atomic...... the point of sample injection/introduction to the point of detection. Hence, in FI-fAAS this feature allows not only to obtain improved repeatability but also improved accuracy, and because the wash to sample ratio is high it permits the handling of samples with elevated salt contents - which...

  4. 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.

  5. Temperature-controlled electrothermal atomization-atomic absorption spectrometry using a pyrometric feedback system in conjunction with a background monitoring device

    Science.gov (United States)

    Van Deijck, W.; Roelofsen, A. M.; Pieters, H. J.; Herber, R. F. M.

    The construction of a temperature-controlled feedback system for electrothermal atomization-atomic absorption spectrometry (ETA-AAS) using an optical pyrometer applied to the atomization stage is described. The system was used in conjunction with a fast-response background monitoring device. The heating rate of the furnace amounted to 1400° s -1 with a reproducibility better than 1%. The precision of the temperature control at a steady state temperature of 2000°C was 0.1%. The analytical improvements offered by the present system have been demonstrated by the determination of cadmium and lead in blood and finally by the determination of lead in serum. Both the sensitivity and the precision of the method have been improved. The accuracy of the method was checked by determining the lead content for a number of scrum samples both by ETA-AAS and differential pulse anodic stripping voltametry (DPASV) and proved to be satisfactory.

  6. 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.

  7. 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.

  8. [Determination of trace elements in Aloe barbadensis Miller irrigated with seawater by atomic absorption spectrophotometry].

    Science.gov (United States)

    Liu, Chun-Hui; Wang, Chang-Hai; Liu, Zhao-Pu

    2008-03-01

    The dry leaves of Aloe barbadensis Miller irrigated with seawater were dissolved in nitric acid and then oxygenated by perchloric acid. Nine kinds of trace elements in the samples were determined by atomic absorption spectrophotometry, including calcium, potassium, magnesium, sodium, manganese, zinc, iron, copper and lead, with added lanthanum chloride as releaser to eliminate the interference of co-existent ions. The recoveries were 96.58%-104.31%, and the relative standard deviations of sample determination (10 times) were less than 2%. This method is simple, sensitive and rapid with satisfactory results and good reproducibility. The results indicated that there were rich Ca, Mg, K and Na, and moderate Mn, Zn and Fe elements in the Aloe barbadensis Miller irrigated with seawater. However, the concentrations of Cu and Pb were low. Therefore, Aloe barbadensis Miller irrigated with seawater has officinal and economic values. These results provide data for further research on Aloe barbadensis Miller irrigated with seawater.

  9. Determination of thallium in wine by electrothermal atomic absorption spectrometry after extraction preconcentration

    Science.gov (United States)

    Cvetković, Julijana; Arpadjan, Sonja; Karadjova, Irina; Stafilov, Trajče

    2002-06-01

    A simple method for extraction electrothermal atomic absorption spectroscopy (ETAAS) determination of Tl in wine is described. The wine sample is decomposed with a mixture of nitric acid and hydrogen peroxide and both thallium species Tl(I) and Tl(III) are extracted from 0.5 mol l -1 KI solution into iso-butyl methyl ketone (IBMK). Optimal parameters for ETAAS measurement of the iodide complexes extracted were defined for two different instruments: Perkin Elmer Zeeman 3030 (HGA 600) and Varian SpectrAA-880 (GTA-100). Modifiers of tartaric acid, Pd [ammoniumtetrachloropaladate (II)] or Ag (silver nitrate) were investigated for thermal stabilization of such extremely volatile species as iodide complexes of Tl. The analytical procedure developed permits 50-fold preconcentration and determination of 0.05 μg l -1 Tl in wine. The relative standard deviation ranges from 6 to 12% for the concentration range 0.2-1 μg l -1 Tl in wine.

  10. 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.

  11. 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%.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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

  17. 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

    -Right-Pointing-Pointer The method provides using of the absorption line within broader working range. Black-Right-Pointing-Pointer The algorithm was applied with the tube, platform and filter furnace atomizers. Black-Right-Pointing-Pointer Ag, Cd, Cu, Fe, Mn and Pb solutions from0.15 to 625 Micro-Sign g/L were analyzed directly.

  18. 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).

  19. 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.

  20. 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...

  1. 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.

  2. 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

  3. 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.

  4. 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.

  5. Optical method of atomic ordering estimation

    Energy Technology Data Exchange (ETDEWEB)

    Prutskij, T. [Instituto de Ciencias, BUAP, Privada 17 Norte, No 3417, col. San Miguel Huyeotlipan, Puebla, Pue. (Mexico); Attolini, G. [IMEM/CNR, Parco Area delle Scienze 37/A - 43010, Parma (Italy); Lantratov, V.; Kalyuzhnyy, N. [Ioffe Physico-Technical Institute, 26 Polytekhnicheskaya, St Petersburg 194021, Russian Federation (Russian Federation)

    2013-12-04

    It is well known that within metal-organic vapor-phase epitaxy (MOVPE) grown semiconductor III-V ternary alloys atomically ordered regions are spontaneously formed during the epitaxial growth. This ordering leads to bandgap reduction and to valence bands splitting, and therefore to anisotropy of the photoluminescence (PL) emission polarization. The same phenomenon occurs within quaternary semiconductor alloys. While the ordering in ternary alloys is widely studied, for quaternaries there have been only a few detailed experimental studies of it, probably because of the absence of appropriate methods of its detection. Here we propose an optical method to reveal atomic ordering within quaternary alloys by measuring the PL emission polarization.

  6. 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.).

  7. 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.

  8. combination of flame atomic absorption spectrometry with ligandless ...

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    A new ligandless-dispersive liquid–liquid microextraction method has been developed for the ... lead levels as low as 100 µg L−1 are associated with adverse health effects in children [1]. The ... The instrumental parameters were adjusted.

  9. 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)

  10. 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...

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. Method and apparatus for atomic imaging

    Science.gov (United States)

    Saldin, Dilano K.; de Andres Rodriquez, Pedro L.

    1993-01-01

    A method and apparatus for three dimensional imaging of the atomic environment of disordered adsorbate atoms are disclosed. The method includes detecting and measuring the intensity of a diffuse low energy electron diffraction pattern formed by directing a beam of low energy electrons against the surface of a crystal. Data corresponding to reconstructed amplitudes of a wave form is generated by operating on the intensity data. The data corresponding to the reconstructed amplitudes is capable of being displayed as a three dimensional image of an adsorbate atom. The apparatus includes a source of a beam of low energy electrons and a detector for detecting the intensity distribution of a DLEED pattern formed at the detector when the beam of low energy electrons is directed onto the surface of a crystal. A device responsive to the intensity distribution generates a signal corresponding to the distribution which represents a reconstructed amplitude of a wave form and is capable of being converted into a three dimensional image of the atomic environment of an adsorbate atom on the crystal surface.

  17. 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.

  18. 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.

  19. The Determination of Lead in Gasoline by Atomic Absorption Spectrometry.

    Science.gov (United States)

    Coleman, M. F. M.

    1985-01-01

    Describes an experiment that involves the extraction of lead from gasoline into an aqueous solvent using iodine monochloride reagent. This method (which avoids the aspiration of organic solvents) also illustrates the use of wavelengths other than the most sensitive wavelength and effects of flame stoichiometry and burner height upon absorbance.…

  20. 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.

  1. 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.

  2. 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.

  3. [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.

  4. 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.

  5. 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.

  6. [Determination of nine mineral elements in hulless barley by ultraviolet spectrophotometry and flame atomic absorption spectrometry].

    Science.gov (United States)

    Liu, Jin; Zhang, Huai-Gang

    2010-04-01

    The contents of nine mineral elements, including sulphur, zinc, calcium, magnesium, potassium, sodium, iron, copper and manganese in five hulless barley (Hordeum vulgare L. var. nudum Hook. f.) lines were determined by ultraviolet spectrophotometry and flames atomic absorption spectrometry (FAAS). For the determination of sulphur, the samples were dissolved by magnesia and anhydrous sodium carbonate at 250 degrees C for 0. 5 h and at 550 degrees C for 3 h in the muffle furnace, and then a certain amount of barium chloride was put into the sample solution for colorimetry of the UV-Vs spectrophotometer. For the determination of other eight mineral elements, all of the samples were dissolved by a kind of incinerating method: first, the sample was put into the muffle furnace at 250 degrees C for 0. 5 h and at 550 degrees C for 2.5 h, then two droplets of 50%HNO3 were distributed into each sample, and the last step was putting the sample into the muffle furnace at 550 degrees C for 0.5 h. And then all of the ash was dissolved by 50%HNO3 to 50 milliliter and determined by flames atomic absorption spectrometry. The precision, accuracy, repeatability and stability of the method were discussed too. The results showed that the relative standard deviations (RSD) were between 1.2% and 3.7%; The average recoveries were 97.44%-101.52% and the relative standard deviations (RSD) of sample determination were 1.3%-3.8%. The repeatability experiment showed that the relative standard deviations (RSD) were 2.6%-6.1%. And the content of each mineral element was the same after 24 hours; All these showed that the method has a good precision, accuracy, repeatability and stability. In all the hulless barley samples, the average contents were in the order of K > S > Mg > Ca > Fe > Na > Zn > Mn > Cu, and the contents of zinc, iron and manganese closely related to people's health were relatively higher than other crops. The data of the experiment could provide an accurate and credible evidence

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. A new atomic absorption spectral assay for the determination of trace IgG using immunonanogold.

    Science.gov (United States)

    Tang, Yafang; Jiang, Caina; Liang, Aihui; Li, Jishun; Jiang, Zhiliang

    2011-05-01

    Nanogold in size of 10 nm was used to label goat anti-human IgG (GIgG) to obtain an immunonanogold probe (AuGIgG) for IgG. In pH 6.8 phosphate buffer solution and in the presence of immunoprecipitator polyethylene glycol 6000 (PEG 6000), IgG reacted with the probe (AuGIgG) to form AuGIgG-IgG-PEG immunocomplex. After the centrifugation to remove the immunocomplex, AuGIgG in the supernatant can be measured by atomic absorption spectrophotometry at gold absorption line 242.8 nm. The results showed that the absorption value decreased as the concentration of IgG increased, and the decreased absorption value was linear to IgG concentration in the range 0.025-0.375 μg/mL, with a detection limit of 0.008 μg/mL. On this base, a new nanogold-labeled atomic absorption spectral assay for IgG was established. The assay was applied to determine IgG in human serum sample with satisfactory results.

  14. 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.

  15. Determination of absolute configuration using heavy atom based co-crystallization method: Halogen atom effects

    Science.gov (United States)

    Wang, Jian-Rong; Fan, Xiaowu; Ding, Qiaoce; Mei, Xuefeng

    2016-09-01

    Heavy atom (chloride, bromide, and iodide) based co-crystals for determination of absolute configuration (AC) for chiral molecules were synthesized and evaluated. Co-crystals of cholestanol and L-ascorbic acid were analysed and the effects and potential benefits of varying the heavy atom are discussed. Changing the halogen atoms (chloride, bromide, or iodide) affects the co-crystal formation, X-ray absorption, and anomalous dispersion, and hence the ability to determine AC.

  16. 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.

  17. 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.

  18. 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.

  19. Determination of calcium and magnesium in hydroethanolic extracts of propolis by atomic absorption flame spectrophotometry

    Directory of Open Access Journals (Sweden)

    E. Q. SANTANA

    2009-01-01

    Full Text Available

    Propolis is a natural product collected by honeybees and has a large range of pharmacological activity, including antimicrobial, antitumoral, antioxidant and anti-inflammatory. Its use as a popular medicine is increasing all over the world, creating a need for quality control of the commercial products. In this study the levels of calcium and magnesium in commercial hydroalcoholic propolis extracts from varios states of Brazil were determined by atomic absorption flame spectrophotometry and different values were obtained for northern and southern states. This study can be extended to the analysis of metals that are harmful to health. The results showed that the calibration curves were linear over a wide concentration range (0.5-4.0 µg.mL-1 for calcium and 0.05-0.4 µg.mL-1 for magnesium with good correlation coefficients (0.999 and 0.988, respectively. Good analytical recovery (94% was obtained. The proposed method showed adequate precision and relative standard deviation lower than 2 %. The method is accurate and precise as well as having advantages such as simplicity and speed. Keywords: hydroalcoholic propolis extract; mineralization; analysis; calcium; magnesium.

  20. 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).

  1. [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%.

  2. 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.

  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. 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.

  5. 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.

  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. 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...

  8. 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......, programmable from the microcomputer, to control the sample volume. No pre-treatment of the samples is necessary. The limit of detection is 0.14 mg l–1, and only small amounts of serum (

  9. 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...

  10. 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.

  11. A method for determination mass absorption coefficient of gamma rays by Compton scattering.

    Science.gov (United States)

    El Abd, A

    2014-12-01

    A method was proposed for determination mass absorption coefficient of gamma rays for compounds, alloys and mixtures. It is based on simulating interaction processes of gamma rays with target elements having atomic numbers from Z=1 to Z=92 using the MCSHAPE software. Intensities of Compton scattered gamma rays at saturation thicknesses and at a scattering angle of 90° were calculated for incident gamma rays of different energies. The obtained results showed that the intensity of Compton scattered gamma rays at saturations and mass absorption coefficients can be described by mathematical formulas. These were used to determine mass absorption coefficients for compound, alloys and mixtures with the knowledge of their Compton scattered intensities. The method was tested by calculating mass absorption coefficients for some compounds, alloys and mixtures. There is a good agreement between obtained results and calculated ones using WinXom software. The advantages and limitations of the method were discussed.

  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. Digital atomic force microscope Moire method

    Energy Technology Data Exchange (ETDEWEB)

    Liu, C.-M. [Department of Mechanical Engineering, National Cheng Kung University, Tainan 70101, Taiwan (China); Chen, L.-W. [Department of Mechanical Engineering, National Cheng Kung University, Tainan 70101, Taiwan (China)]. E-mail: chenlw@mail.ncku.edu.tw

    2004-11-15

    In this study, a novel digital atomic force microscope (AFM) moire method is established to measure the displacement and strain fields. The moire pattern is generated by the interference between the specimen grating and the virtual reference grating formed by digital image processes. The overlapped image is filtered by the 2-D wavelet transformation to obtain clear interference moire patterns. From moire patterns, the displacement and strain fields can be analyzed. The experimental results show that the digital AFM moire method is very sensitive and easy to realize in nanoscale measurements.

  15. [Study on determination of eight metal elements in Hainan arecanut leaf by flame atomic absorption spectrophotometry].

    Science.gov (United States)

    Liu, Li-yun; Wang, Ping; Feng, Mei-li; Dong, Zhi-guo; Li, Jie

    2008-12-01

    Arecanut is a sort of palm that is important economic crop for the farmers in Hainan province of China, wherein there are many kinds of metal elements such as K, Ca, Na, Mg, Fe, Mn, Cu, Zn etc. These elements are important nutrition for the growth of arecanut. It is very valuable to study on the content of these metal elements in arecanut leaf in terms of plant nutriology of arecanut. The arecanut leaf in Wangling county, Hainan province of China was sampled by diagonal-field-sampling method. Refering to other plant sample determination by FAAS, the detailed studies are done with different digestion and determination methods. In the present paper the effects of mixed acid of HNO3-HClO4 digestion method on determining the amount of metal elements in the arecanut leaf by FAAS is reported, and another one is incineration digestion method. FAAS method was established for the determination of K, Ca, Mg, Na, Fe, Mn, Cu and Zn The samples were incinerated or heated with HNO3-HClO4 (4:1). In the meantime, the optimum parameters of FAAS and effects of different digestion methods on the results were discussed. The recovery rate of standard addition is 98.36%-102.38% in the first method; RSD is 0.42%-2.328% (n=6); The recovery rate of standard addition is 99.22%-103.72% in the second method; RSD is 0.58%-1.283 (n=6). The metal amount determined by the first method is lower than the second method, the ratio is 0.9703-0.9934. The two methods are satisfied, but the latter is better. It is precise enough to common experiment to use flame atomic absorption spectrophotometry with digestion by incineration If the especially precise experiment is required, the digestion methods with mixed acid of HNO3-HClO4 may be introduced. The paper introduced methods dependable for determination of some metal elements in order to study on some nutrient effects of these metal elements in arecanut.

  16. 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.

  17. Highly sensitive fiber grating chemical sensors: An effective alternative to atomic absorption spectroscopy

    Science.gov (United States)

    Laxmeshwar, Lata. S.; Jadhav, Mangesh S.; Akki, Jyoti. F.; Raikar, Prasad; Kumar, Jitendra; prakash, Om; Raikar, U. S.

    2017-06-01

    Accuracy in quantitative determination of trace elements like Zinc, present in drinking water in ppm level, is a big challenge and optical fiber gratings as chemical sensors may provide a promising solution to overcome the same. This paper presents design of two simple chemical sensors based on the principle of shift in characteristic wavelength of gratings with change in their effective refractive index, to measure the concentration of Zinc in drinking water using etched short period grating (FBG) and Long period grating (LPG) respectively. Three samples of drinking water from different places have been examined for presence of Zinc. Further, the results obtained by our sensors have also been verified with the results obtained by a standard method, Atomic absorption spectroscopy (AAS). The whole experiment has been performed by fixing the fibers in a horizontal position with the sensor regions at the center of the fibers, making it less prone to disturbance and breaking. The sensitivity of LPG sensor is about 205 times that of the FBG sensor. A few advantages of Fiber grating sensors, besides their regular features, over AAS have also been discussed, that make our sensors potential alternatives for existing techniques in determination of trace elements in drinking water.

  18. [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.

  19. [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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. Ion-exchange preconcentration and determination of vanadium in milk samples by electrothermal atomic absorption spectrometry.

    Science.gov (United States)

    López-García, Ignacio; Viñas, Pilar; Romero-Romero, Rafael; Hernández-Córdoba, Manuel

    2009-06-15

    A new method for the electrothermal atomic absorption spectrometric determination of vanadium in milk and infant formulas using suspensions to avoid the need for previous dissolution of samples is described. Sensitivity is improved by a procedure based on preconcentration and removal of the matrix, using ion-exchange (Dowex 1X8-100). Suspensions of 15% (m/v) infant formula samples were prepared in a medium containing 0.05M sodium citrate (pH 7.2) and passed through the ion exchange column. Vanadium was eluted from the column using 1M hydrochloric acid and injected in the graphite furnace using a mixture of hydrofluoric acid plus magnesium nitrate as chemical modifiers. Calibration was carried out using multiple injection and aqueous standards prepared in the same medium. Detection limits were 0.2 ng g(-1) for infant formulas and 0.02 microg L(-1) for cow milk samples. The reliability of the procedure was checked by comparing the results obtained with those found using a previous mineralization stage and by analyzing five certified reference materials.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. [Application of solid sampling graphite furnace atomic absorption spectrophotometry to mensuration of brain iron content in rats].

    Science.gov (United States)

    Zhang, Nan; Sheng, Qing-hai; Shi, Zhen-hua; Zhang, Zhi-guo; Duan, Xiang-lin; Chang, Yan-zhong

    2009-04-01

    In the present study, the authors performed the solid sampling and detected the iron levels in cortex, hippocampus and striatum of rat brain by GFAAS. The authors' results showed that there are no remarkable difference between the data obtained by solid sampling graphite furnace atomic absorption and liquid sampling graphite furnace atomic absorption. Compared to liquid sampling graphite furnace atomic absorption, the sample pre-treatment stage was obviously simplified, the cost was reduced significantly, and the time was shortened significantly in the solid sampling GFAAS. This study will be beneficial to the mensuration of iron content in micro-tissue of animal by solid sampling GFASS.

  12. 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

  13. High-contrast sub-Doppler absorption spikes in a hot atomic vapor cell exposed to a dual-frequency laser field

    Science.gov (United States)

    Abdel Hafiz, Moustafa; Brazhnikov, Denis; Coget, Grégoire; Taichenachev, Alexei; Yudin, Valeriy; de Clercq, Emeric; Boudot, Rodolphe

    2017-07-01

    The saturated absorption technique is an elegant method widely used in atomic and molecular physics for high-resolution spectroscopy, laser frequency standards and metrology purposes. We have recently discovered that a saturated absorption scheme with a dual-frequency laser can lead to a significant sign reversal of the usual Doppler-free dip, yielding a deep enhanced-absorption spike. In this paper, we report detailed experimental investigations of this phenomenon, together with a full in-depth theoretical description. It is shown that several physical effects can support or oppose the formation of the high-contrast central spike in the absorption profile. The physical conditions for which all these effects act constructively and result in very bright Doppler-free resonances are revealed. Apart from their theoretical interest, results obtained in this manuscript are of great interest for laser spectroscopy and laser frequency stabilization purposes, with applications in laser cooling, matter-wave sensors, atomic clocks or quantum optics.

  14. Determination of gold in copper-bearing sulphide ores and metallurgical flotation products by atomic-absorption spectrometry.

    Science.gov (United States)

    Strong, B; Murray-Smith, R

    1974-12-01

    A method is described which is specific for the determination of gold in sulphide copper ores and concentrates. Direct decomposition with aqua regia was found to be incomplete. A carefully controlled roasting stage followed by treatment with hydrochloric acid and then aqua regia was effective for dissolving all the gold. The gold is extracted into 4-methylpentan-2-one (methyli-sobutylketone) then aspirated into a very lean air-acetylene flame and the gold determined by atomic-absorption spectrometry. No interferences were observed from large concentrations of copper, iron or nickel.

  15. 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...

  16. 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.

  17. 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)

  18. 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.

  19. 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.)

  20. Examination of the Measurement of Absorption Using the Reverberant Room Method for Highly Absorptive Acoustic Foam

    Science.gov (United States)

    Hughes, William O.; McNelis, Anne M.; Chris Nottoli; Eric Wolfram

    2015-01-01

    The absorption coefficient for material specimens are needed to quantify the expected acoustic performance of that material in its actual usage and environment. The ASTM C423-09a standard, "Standard Test Method for Sound Absorption and Sound Absorption Coefficients by the Reverberant Room Method" is often used to measure the absorption coefficient of material test specimens. This method has its basics in the Sabine formula. Although widely used, the interpretation of these measurements are a topic of interest. For example, in certain cases the measured Sabine absorption coefficients are greater than 1.0 for highly absorptive materials. This is often attributed to the diffraction edge effect phenomenon. An investigative test program to measure the absorption properties of highly absorbent melamine foam has been performed at the Riverbank Acoustical Laboratories. This paper will present and discuss the test results relating to the effect of the test materials' surface area, thickness and edge sealing conditions. A follow-on paper is envisioned that will present and discuss the results relating to the spacing between multiple piece specimens, and the mounting condition of the test specimen.

  1. Determination of Pb in Biological Samples by Graphite Furnace Atomic Absorption Spectrophotometry: An Exercise in Common Interferences and Fundamental Practices in Trace Element Determination

    Science.gov (United States)

    Spudich, Thomas M.; Herrmann, Jennifer K.; Fietkau, Ronald; Edwards, Grant A.

    2004-01-01

    An experiment is conducted to ascertain trace-level Pb in samples of bovine liver or muscle by applying graphite furnace atomic absorption spectrophotometry (GFAAS). The primary objective is to display the effects of physical and spectral intrusions in determining trace elements, and project the usual methods employed to minimize accuracy errors…

  2. 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.

  3. 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.

  4. 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

  5. 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...

  6. High durability solar absorptive coating and methods for making same

    Energy Technology Data Exchange (ETDEWEB)

    Hall, Aaron C.; Adams, David P.

    2016-11-22

    The present invention relates to solar absorptive coatings including a ceramic material. In particular, the coatings of the invention are laser-treated to further enhance the solar absorptivity of the material. Methods of making and using such materials are also described.

  7. 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.

  8. 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.

  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. 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

  11. Atomic Absorption Spectrometry in Wilson's Disease and Its Comparison with Other Laboratory Tests and Paraclinical Findings

    Science.gov (United States)

    Mahjoub, Fatemeh; Fereiduni, Rana; Jahanzad, Isa; Farahmand, Fatemeh; Monajemzadeh, Maryam; Najafi, Mehri

    2012-01-01

    Objective Wilson's disease (WD) is an autosomal recessive disease with genetic abnormality on chromosome 13 causing defect in copper metabolism and increased copper concentration in liver, central nervous system and other organs, which causes different clinical manifestations. The aim of this study was to determine the sensitivity of different clinical and paraclinical tests for diagnosis of Wilson's disease. Methods Paraffin blocks of liver biopsy from 41 children suspicious of WD were collected. Hepatic copper concentrations were examined with atomic absorption spectrophotometry (Australian GBC, model: PAL 3000). Fifteen specimens had hepatic copper concentration (dry weight) more than 250μg/g. Clinical and laboratory data and histologic slides of liver biopsies of these 15 children were reviewed retrospectively. Liver tissue was examined for staging and grading of hepatic involvement and also stained with rubeonic acid method for copper. Findings Patients were 5-15 years old (mean age=9.3 years, standard deviation=2.6) with slight male predominance (9/15=60%). Five (33%) patients were 10 years old. Three (20%) of them were referred for icterus, 8 (54%) because of positive family history, 2 (13%) due to abdominal pain and 2 (13%) because of hepatosplenomegaly and ascites. Serum AST and ALT levels were elevated at the time of presentation in all patients. In liver biopsy, histological grade and stage was 0-8 and 0-6 respectively, 2 (13%) had cirrhosis, 1 (7%) had normal biopsy and 12 (80%) showed chronic hepatitis. Hepatic copper concentrations were between 250 and 1595 μg/g dry weight. The sensitivity of various tests were 85% for serum copper, 83% for serum ceruloplasmin, 53% for urinary copper excretion, 44% for presence of KF ring and 40% for rubeonic acid staining on liver biopsies. Conclusion None of the tests stated in the article were highly sensitive for diagnosis of WD, so we suggest that diagnosis should be based on combination of family history

  12. The determination of total calcium in urine: a comparison between the atomic absorption and the ortho-cresolphtalein complexone methods Análise do cálcio na urina: uma comparação entre os métodos de absorção atômica e ortocresolftaleína complexona

    Directory of Open Access Journals (Sweden)

    Lucia Simas Parentoni

    2001-01-01

    Full Text Available Atomic absorption spectrometry has been recommended as the reference method for the analysis of total calcium in body fluids and the ortho-cresolphtalein complexone (o-CPC method has been widely used as the field method. We evaluated the performance of the Mega-Bayer, a fully automatic selective analyser, in determining total calcium in urine utilizing the o-CPC method. We assayed native urines with low, normal and high calcium concentrations. The two methods agreed well, according to least-squares analysis and the F-test, with Mega-Bayer having the upper limit of linearity two times higher (10 mmol/L than that of the atomic absorption. The present method achieved excellent analytical goals and sistematic errors bellow half of the allowed limit goals recommended by the Clinical Laboratory Improvements Amendments. Final Rule. Laboratory Requirements (CLIA. We concluded that o-CPC in the Mega-Bayer equipment can confidently perform the total calcium urinary analysis with the advantage of being a fully automatized biochemical procedure and of allowing a wider linear analytical range.A espectrofotometria de absorção atômica é o método de referência para a análise do cálcio total em líquidos corporais, e o método da ortocresolftalína complexona (o-CPC tem sido utilizado rotineiramente. Avaliamos a performance do Mega-Bayer, um analisador seletivo automático, em determinar o cálcio total na urina utilizando o método da ortocresolftaleína complexona. Analisamos urinas com concentrações de cálcio baixas, médias e altas. Os dois métodos foram semelhantes de acordo com a análise de quadrados mínimos e o teste-F; o Mega-Bayer apresentou um limite de linearidade duas vezes mais alto (10mm/l do que a absorção atômica. O presente método atingiu excelentes metas analíticas, além de erros sistemáticos menores que a metade do permitido pelo Clinical Laboratory Improvements Amendments. Final Rule. Laboratory Requirements (CLIA. Conclu

  13. Trace element determination-I Use of 2,9-dimethyl-1,10-phenanthroline in determination of copper in heavy matrices by carbon furnace atomic-absorption spectrometry.

    Science.gov (United States)

    Battistoni, P; Bruni, P; Cardellini, L; Fava, G; Gobbi, G

    1980-08-01

    A method for the determination of copper in complex matrices by electrothermal atomic-absorption spectrometry has been developed. It uses neocuproine as complexing agent. The detection limit is 0.2 ng/ml, and interferences are minimized.

  14. 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

  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. 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.

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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...

  3. 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.

  4. Simultaneous determination of rhodium and ruthenium by high-resolution continuum source graphite furnace atomic absorption spectrometry

    Science.gov (United States)

    Zambrzycka-Szelewa, Elżbieta; Lulewicz, Marta; Godlewska-Żyłkiewicz, Beata

    2017-07-01

    In the present paper a fast, simple and sensitive analytical method for simultaneous determination of rhodium and ruthenium by high-resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS GFAAS) was developed. Among six pairs of absorption atomic lines of Rh and Ru, which are close enough to enable their simultaneous detection, two pairs were selected for further studies. Best results were obtained for measurements of the resonance line of rhodium at 343.489 nm and the adjacent secondary line of ruthenium at 343.674 nm (23% intensity of this line). For evaluated lines, the absorbance values were obtained using three pixels. The pyrolysis and atomization temperatures were 1200 °C and 2600 °C, respectively. Under these conditions the limits of detection achieved for Rh and Ru were found to be 1.0 μg L- 1 and 1.9 μg L- 1, respectively. The characteristic mass was 12.9 pg for Rh and 71.7 pg for Ru. Repeatability of the results expressed as a relative standard deviation was typically below 6%. The trueness of the method was confirmed by analysis of the certified reference material - platinum ore (SARM 76). The recovery of Rh and Ru from the platinum ore was 93.0 ± 4.6% and 90.1 ± 2.5%, respectively. The method was successfully applied to the direct simultaneous determination of trace amounts of rhodium and ruthenium in spiked river water, road runoff, and municipal sewage. Separation of interfering matrix on cation exchange resin was required before analysis of road dust and tunnel dust (CW-7) by HR-CS GFAAS.

  5. Effective atomic numbers of some tissue substitutes by different methods: A comparative study

    Directory of Open Access Journals (Sweden)

    Vishwanath P Singh

    2014-01-01

    Full Text Available Effective atomic numbers of some human organ tissue substitutes such as polyethylene terephthalate, red articulation wax, paraffin 1, paraffin 2, bolus, pitch, polyphenylene sulfide, polysulfone, polyvinylchloride, and modeling clay have been calculated by four different methods like Auto-Z eff, direct, interpolation, and power law. It was found that the effective atomic numbers computed by Auto-Z eff , direct and interpolation methods were in good agreement for intermediate energy region (0.1 MeV < E < 5 MeV where the Compton interaction dominates. A large difference in effective atomic numbers by direct method and Auto-Z eff was observed in photo-electric and pair-production regions. Effective atomic numbers computed by power law were found to be close to direct method in photo-electric absorption region. The Auto-Z eff , direct and interpolation methods were found to be in good agreement for computation of effective atomic numbers in intermediate energy region (100 keV < E < 10 MeV. The direct method was found to be appropriate method for computation of effective atomic numbers in photo-electric region (10 keV < E < 100 keV. The tissue equivalence of the tissue substitutes is possible to represent by any method for computation of effective atomic number mentioned in the present study. An accurate estimation of Rayleigh scattering is required to eliminate effect of molecular, chemical, or crystalline environment of the atom for estimation of gamma interaction parameters.

  6. Modified embedded atom method calculations of interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Baskes, M.I.

    1996-05-01

    The Embedded Atom Method (EAM) is a semi-empirical calculational method developed a decade ago to calculate the properties of metallic systems. By including many-body effects this method has proven to be quite accurate in predicting bulk and surface properties of metals and alloys. Recent modifications have extended this applicability to a large number of elements in the periodic table. For example the modified EAM (MEAM) is able to include the bond-bending forces necessary to explain the elastic properties of semiconductors. This manuscript will briefly review the MEAM and its application to the binary systems discussed below. Two specific examples of interface behavior will be highlighted to show the wide applicability of the method. In the first example a thin overlayer of nickel on silicon will be studied. Note that this example is representative of an important technological class of materials, a metal on a semiconductor. Both the structure of the Ni/Si interface and its mechanical properties will be presented. In the second example the system aluminum on sapphire will be examined. Again the class of materials is quite different, a metal on an ionic material. The calculated structure and energetics of a number of (111) Al layers on the (0001) surface of sapphire will be compared to recent experiments.

  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. Method of performing MRI with an atomic magnetometer

    Science.gov (United States)

    Savukov, Igor Mykhaylovich; Matlashov, Andrei Nikolaevich; Espy, Michelle A; Volegov, Petr Lvovich; Kraus, Jr., Robert Henry; Zotev, Vadim Sergeyevich

    2013-08-27

    A method and apparatus are provided for performing an in-situ magnetic resonance imaging of an object. The method includes the steps of providing an atomic magnetometer, coupling a magnetic field generated by magnetically resonating samples of the object through a flux transformer to the atomic magnetometer and measuring a magnetic resonance of the atomic magnetometer.

  9. 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.

  10. 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.

  11. Atomic hydrogen storage method and apparatus

    Science.gov (United States)

    Woollam, J. A. (Inventor)

    1980-01-01

    Atomic hydrogen, for use as a fuel or as an explosive, is stored in the presence of a strong magnetic field in exfoliated layered compounds such as molybdenum disulfide or an elemental layer material such as graphite. The compounds maintained at liquid helium temperatures and the atomic hydrogen is collected on the surfaces of the layered compound which are exposed during delamination (exfoliation). The strong magnetic field and the low temperature combine to prevent the atoms of hydrogen from recombining to form molecules.

  12. 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.

  13. 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.

  14. [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.

  15. 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}.

  16. 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 .

  17. 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.

  18. 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

  19. Indium determination in different environmental materials by electrothermal atomic absorption spectrometry with Amberlite XAD-2 coated with 1-(2-pyridylazo)-2-naphthol.

    Science.gov (United States)

    Martínez A, N C; Barrera, Adela Bermejo; Bermejo B, P

    2005-04-30

    Methods were developed for indium (In) determination in complex ores by electrothermal atomization atomic absorption spectrometry using matrix modification after its separation with Amberlite XAD-2 coated with 1-(2-pyridylazo)-2-naphthol (PAN). Palladium-magnesium, nickel, and zinc nitrates were used as matrix modifiers and were compared in terms of maximum pyrolysis temperature, sensitivity and background signal. They have enhanced the absorption signals for indium, respectively eliminating the matrix interferences. The standard additions method was applied. The relative standard deviations for six replicate determinations were in the range 0.3-4.0% for indium in different ores samples for indium concentrations 7.6-209mugg(-1). The recommended method was applied to the indium determination in real samples. The data obtained by this method were in good agreement with those obtained by ICP-AES.

  20. 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...

  1. [Speciation analysis of trace elements Cu, Fe and Zn in serum by flame atomic absorption spectrophotometry].

    Science.gov (United States)

    Hu, Jun; Chang, Yao-Ming; Gao, Shuang-Bin; Hai, Chun-Xu; Li, Jin-Sheng; Xie, Xiao-Ping

    2008-03-01

    Since biological functions of the elements are generally different, depending on their chemical forms, chemical speciation analysis is really important in metallomics research. Thus, multielement analysis and chemical speciation of the elements in serum were carried out in the present work. A hyphenated technique was developed for high-throughput speciation analysis of the copper, iron and zinc in serum by molecular biology technology and flame atomic absorption spectrophotometry (AAS). Here, Cu, Fe and Zn in serum were classifyied as the forms of combination and non-combination. The serum protein was precipitated by 60% concentration of ethanol under hypothermy. The forms of combination of Cu, Fe and Zn in serum which combined with proteins were in precipitations, and the forms of non-combination of Cu, Fe and Zn in serum, which were free ions, were in supernatant. The total amount of Cu, Fe and Zn in serum and the amount of the forms of non-combination of Cu, Fe and Zn were analyzed by AAS. The amount of the forms of combination of Cu, Fe and Zn was obtained by calculation. The detection limit of Cu in serum by the method is around and 9.84 x 10(-3) microg x mL(-1). For Fe and Zn, the detection limit is about 2.76 x 10(-2) microg x mL(-1) and 1.06 x 10(-3) microg x mL(-1), respectively. The percentage recovery of trace elements Cu, Fe and Zn by the proposed procedure is in the range 95.0%-101.0%, 95.0%-102.0% and 95.0%-103.0%, respectively. The relative standard deviation (RSD) of trace elements Cu, Fe and Zn in the serum is in the range 1.88%-2.26%, 0.56%-1.59% and 0.34%-1.36%, respectively. Speciation of trace elements Cu, Fe and Zn in the serum of SD rat were analyzed by the method.

  2. History of early atomic clocks

    Energy Technology Data Exchange (ETDEWEB)

    Ramsey, N.F. [Harvard Univ., Cambridge, MA (United States). Lyman Lab. of Physics

    2005-06-01

    This review of the history of early atomic clocks includes early atomic beam magnetic resonance, methods of separated and successive oscillatory fields, microwave absorption, optical pumping and atomic masers. (author)

  3. 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.

  4. 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.)

  5. 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.

  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. 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.

  8. 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.

  9. 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.

  10. 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 ...

  11. 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).

  12. 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.

  13. 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).

  14. 石墨炉原子吸收法测定全血标本铅含量的3种前处理方法%Comparison of three specimen pretreatment methods for measuring lead content in whole blood by graphite furnace a-tomic absorption spectrometry

    Institute of Scientific and Technical Information of China (English)

    张斯恩; 张贝基; 谭红丽

    2014-01-01

    比较石墨炉原子吸收法测定全血标本中铅的3种前处理方法优劣,从中筛选一种更简便、准确、灵敏的方法,从而达到提高检测质量,降低工作强度的目的。方法采用酸脱蛋白法、混合基体改进剂法、微波消解法对无铅接触史的健康成年人全血标本进行前处理,分别用石墨炉原子吸收法检测,对检测结果进行统计分析,比较标准曲线线性、相关系数(r)、相对标准偏差(RSD%)、准确度等指标。结果3种方法标准曲线 r分别为0.9965、0.9942、0.9995;检出限分别为5.4、3.6、2.7μg/L ;RSD%分别为4.1、4.5、2.8;回收率分别为95.7%~103.3%、98.7%~104.5%、98.3%~102.3%。结论微波消解处理全血标本各项指标均令人满意,是测量血铅较好的前处理方法。%Objective To compare three specimen pretreatment methods for measuring lead content in whole blood by graphite furnace atomic absorption spectrometry .Methods Whole blood of healthy adults without lead ex‐posure history were pretreated by using acid deproteinized method ,mixed matrix modifier method ,and microwave di‐gestion method ,and then detected for lead content by using graphite furnace atomic absorption spectrometry .All re‐sults were statistically analyzed to compare indicators ,including standard curve′s linear ,correlation coefficient ,rela‐tive standard deviation (RSD% ) ,accuracy and so on .Results Correlation coefficients of standard curve of the three methods were 0 .996 5 ,0 .994 2 and 0 .999 5 ,the minimum detectable concentration were 5 .4 ,3 .6 and 2 .7 μg/L , RSD% were 4 .1 ,4 .5 and 2 .8 ,and the recovery rates were 95 .7% -103 .3% ,98 .7% -104 .5% and 98 .3% -102 .3% .Conclusion The evaluation indicators of microwave digestion method could be satisfactory ,which might be an ideal method for pretreatment of blood specimens for detection of lead content .

  15. Segregation during crystal growth from melt and absorption cross section determination by optical absorption method

    Institute of Scientific and Technical Information of China (English)

    ZHANG QingLi; YIN ShaoTang; SUN DunLu; WAN SongMing

    2008-01-01

    Segregation during crystal growth from melt under two conditions is studied by using crystal mass, which can be measured easily, as an independent variable, and a method to determine the effective segregation coefficient and absorption cross section of optical dopant is given. When the segregated solute disperses into the whole or just a part of melt homogenously, the concentration Cs in solid interface will change by different formulas. If the crystal growth interface is conical and segregated solute disperses into melt in total or part, the solute concentration at r=2/3R, where r is the distance from the growth cross section center and R the crystal radius, is independent on the shape of the crystal growth interface, and its variation at r=2/3R can be regarded as the result from crystal growth in flat interface. With Cs variation formula in solid and absorption cross section σ for optical dopant, the absorption coefficients along the crystal growth direction can be calculated, and the corresponding experimental value can be obtained through the crystal optical absorption spectra. By minimizing the half sum, whose independent variables are k, △W or σ, of the difference square between the calculated and experimental absorp-tion coefficients from one or more absorption peaks along the crystal growth di-rection, k and σ, or k and △W, can be determined at the same time through the Levenberg-Marquardt iteration method. Finally, the effective segregation coefficient k, △W and absorption cross sections of Nd:GGG were determined, the results fitted by two formula gave more closed effective segregation coefficient, and the value △W also indicates that the segregated dopant had nearly dispersed into the whole melt. Experimental results show that the method to determine effective segregation coefficient k, △W and absorption cross sections σ is convenient and reliable, and the two segregation formulas can describe the segregation during the crystal growth from

  16. Segregation during crystal growth from melt and absorption cross section determination by optical absorption method

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Segregation during crystal growth from melt under two conditions is studied by using crystal mass,which can be measured easily,as an independent variable,and a method to determine the effective segregation coefficient and absorption cross section of optical dopant is given.When the segregated solute disperses into the whole or just a part of melt homogenously,the concentration CS in solid interface will change by different formulas.If the crystal growth interface is conical and segregated solute disperses into melt in total or part,the solute concentration at r=2/3R,where r is the distance from the growth cross section center and R the crystal radius,is independent on the shape of the crystal growth interface,and its variation at r=2/3R can be regarded as the result from crystal growth in flat interface.With CS variation formula in solid and absorption cross section σ for optical dopant,the absorption coefficients along the crystal growth direction can be calculated,and the corresponding experimental value can be obtained through the crystal optical absorption spectra.By minimizing the half sum,whose independent variables are k,ΔW or σ,of the difference square between the calculated and experimental absorp-tion coefficients from one or more absorption peaks along the crystal growth di-rection,k and σ,or k and ΔW,can be determined at the same time through the Levenberg-Marquardt iteration method.Finally,the effective segregation coefficient k,ΔW and absorption cross sections of Nd:GGG were determined,the results fitted by two formula gave more closed effective segregation coefficient,and the value ΔW also indicates that the segregated dopant had nearly dispersed into the whole melt.Experimental results show that the method to determine effective segregation coefficient k,ΔW and absorption cross sections σ is convenient and reliable,and the two segregation formulas can describe the segregation during the crystal growth from melt relatively commendably.

  17. Atomic Oxygen Abundance in Molecular Clouds: Absorption Toward Sagittarius B2

    Science.gov (United States)

    Lis, D. C.; Keene, Jocelyn; Phillips, T. G.; Schilke, P.; Werner, M. W.; Zmuidzinas, J.

    2001-01-01

    We have obtained high-resolution (approximately 35 km/s) spectra toward the molecular cloud Sgr B2 at 63 micrometers, the wavelength of the ground-state fine-structure line of atomic oxygen (O(I)), using the ISO-LWS instrument. Four separate velocity components are seen in the deconvolved spectrum, in absorption against the dust continuum emission of Sgr B2. Three of these components, corresponding to foreground clouds, are used to study the O(I) content of the cool molecular gas along the line of sight. In principle, the atomic oxygen that produces a particular velocity component could exist in any, or all, of three physically distinct regions: inside a dense molecular cloud, in the UV illuminated surface layer (PDR) of a cloud, and in an atomic (H(I)) gas halo. For each of the three foreground clouds, we estimate, and subtract from the observed O(I) column density, the oxygen content of the H(I) halo gas, by scaling from a published high-resolution 21 cm spectrum. We find that the remaining O(I) column density is correlated with the observed (13)CO column density. From the slope of this correlation, an average [O(I)]/[(13)CO] ratio of 270 +/- 120 (3-sigma) is derived, which corresponds to [O(I)]/[(13)CO] = 9 for a CO to (13)CO abundance ratio of 30. Assuming a (13)CO abundance of 1x10(exp -6) with respect to H nuclei, we derive an atomic oxygen abundance of 2.7x10(exp -4) in the dense gas phase, corresponding to a 15% oxygen depletion compared to the diffuse ISM in our Galactic neighborhood. The presence of multiple, spectrally resolved velocity components in the Sgr B2 absorption spectrum allows, for the first time, a direct determination of the PDR contribution to the O(I) column density. The PDR regions should contain O(I) but not (13)CO, and would thus be expected to produce an offset in the O(I)-(13)CO correlation. Our data do not show such an offset, suggesting that within our beam O(I) is spatially coexistent with the molecular gas, as traced by (13)CO

  18. 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.

  19. Determination of Fe, Ca, Mg, Zn and Pb in Cinder and Activated Carbon by Flame Atomic Absorption Method%火焰原子吸收法测定煤渣和煤质活性炭中铁、钙、镁、锌、铅

    Institute of Scientific and Technical Information of China (English)

    薛慧; 董宾

    2014-01-01

    A method for measurement of metal microelements in cinders and activated carbon,such as Fe, Ca, Mg, Zn and Pb by flame atomic absorption method was established. Pretreatment procedure was studied. Cinders was treated with dry ashing and then digested,activated carbon was treated with acid extraction method. Metal microelements such as Fe,Ca and Mg in cinder were measured using standard curve method,while microelements such as Fe,Zn and Pb in activated carbon from coal were measured based on standard addition method,in order to reduce the interference of the basic. Results detected by the method were in accordance with existed references. Microelements contents were higher in cinders,especially after burning. In comparison,microelements dropped dramatically in activated carbon, due to the complex processing procedure. Recoveries of each element ranged from 88.5% to 105.5%, and the relative standard deviation was less than 2% (n=7). The detecting limits of the six elements were 0.010,0.015,0.005,0.012,0.013, 0.110 mg/L respectively, in two kinds of the specimen. It can be concluded that the flame atomic absorption method is accurate,convenient, it is suitable for the measurement of metal microelements in cinders and activated carbon.%建立了火焰原子吸收法测定煤渣和煤质活性炭中微量金属元素铁、钙、镁、锌、铅含量的方法。煤渣样品采用干灰化后消解,煤质活性炭样品采用稀酸提取进行处理。煤渣中铁、钙、镁元素用标准曲线法定量,活性炭中铁、锌、铅则采用标准加入法定量以减少基体干扰的影响。样品测定结果与文献报道相一致,煤渣尤其是燃烧处理后的煤渣中微量元素含量较高,而煤质活性炭通过复杂工艺处理后,微量元素大大减少。样品中被测元素的加标回收率在88.5%~105.5%之间,测定结果的相对标准偏差小于2%(n=7),两类样品中6种元素的检出限分别为0.010,0.015,0.005,0.012

  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. Multicomutation flow system for manganese speciation by solid phase extraction and flame atomic absorption spectrometry

    Science.gov (United States)

    Tobiasz, Anna; Sołtys, Monika; Kurys, Ewa; Domagała, Karolina; Dudek-Adamska, Danuta; Walas, Stanisław

    2017-08-01

    In the paper an application of solid phase extraction technique for speciation analysis of manganese in water samples with the use of flame atomic absorption spectrometry is presented. Two types of sorbents, activated silica gel and Dowex 1 × 4, were used respectively for simultaneously Mn2 + and MnO42 - retention and preconcentration. The whole procedure was realized in multicomutation flow system. Different conditions like: type and concentration of eluent, sample pH and loading time were tested during the study. Under appropriate conditions, it was possible to obtained enrichment factors of 20 and 16 for Mn(II) and Mn(VII), respectively. Precision of the procedure was close to 4% (measured as relative standard deviation), whereas the detection limit (3σ) was 1.4 μg·L- 1 for Mn(II) and 4.8 μg·L- 1 for Mn(VII).

  2. 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.)

  3. 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.

  4. 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.

  5. [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.

  6. 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.

  7. 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.

  8. Determination of Zinc Ions in Environmental Samples by Dispersive Liquid- Liquid Micro Extraction and Atomic Absorption Spectroscopy

    Directory of Open Access Journals (Sweden)

    F. Arabi

    2012-11-01

    Full Text Available In this work preconcentration of the Zn ions was investigated in water sample by Dispersive liquid- liquid micro extraction (DLLME using chloroform as an extraction solvent, methanol as a disperser solvent and 8-Hydroxyquinoline as a chelating agent. The determination of extracted ions was done by graphite furnace atomic absorption spectrometry. The influence of various analytical parameters including pH, extraction and disperser solvent type and volume and concentration of the chelating agent on the extraction efficiency of analyses was investigated. After extraction, the enrichment factor was 26 and the detection limit of the method was 0.0033 µg l-1 and the relative standard deviations (R.S.D for five determinations of 1 ng/ml Zn were 7.41%. 

  9. 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.

  10. 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.

  11. Validação de metodologia analítica para determinação de mercúrio total em amostras de urina por espectrometria de absorção atômica com geração de vapor frio (CV-AAS): estudo de caso Validation of an analytical method for the determination of total mercury in urine samples using cold vapor atomic absorption spectrometry (CV-AAS): case study

    National Research Council Canada - National Science Library

    Sabine Neusatz Guilhen; Maria Aparecida Faustino Pires; Elizabeth Sonoda Keiko Dantas; Fernanda Villibor Xavier

    2010-01-01

    .... One of its more dubious uses is in dental amalgam restorations. It is possible to measure very small concentrations of this metal in the urine of exposed subjects by the cold vapor atomic absorption technique...

  12. 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.

  13. Assessing the engagement, learning, and overall experience of students operating an atomic absorption spectrophotometer with remote access technology.

    Science.gov (United States)

    Erasmus, Daniel J; Brewer, Sharon E; Cinel, Bruno

    2015-01-01

    The use of internet-based technologies in the teaching of laboratories has emerged as a promising education tool. This study evaluated the effectiveness of using remote access technology to operate an atomic absorption spectrophotometer in analyzing the iron content in a crude myoglobin extract. Sixty-two students were surveyed on their level of engagement, learning, and overall experience. Feedback from students suggests that the use of remote access technology is effective in teaching students the principles of chemical analysis by atomic absorption spectroscopy. © 2014 The International Union of Biochemistry and Molecular Biology.

  14. Enrichment process of biogas using simultaneous Absorption - Adsorption methods

    Science.gov (United States)

    Kusrini, Eny; Lukita, Maya; Gozan, Misri; Susanto, Bambang Heru; Nasution, Dedy Alharis; Rahman, Arif; Gunawan, Cindy

    2017-03-01

    Removal of CO2 in biogas is an essential methods to the purification and upgrading of biogas. Natural Clinoptilolite zeolites were evaluated as sorbents for purification of biogas that produced from palm oil mill effluent (POME) by anerobic-digestion method. The absorption and adsorption experiments were conducted in a fixed-bed two column adsorption unit by simultaneous absorption-adsorption method. The Ca(OH)2 solution with concentration of 0.062 M was used as absorption method. Sorbent for removal of CO2 in biogas have been prepared by modifying of Clinoptilolite zeolites with an acid (HCl, 2M) and alkaline (NaOH, 2M), calcined at 450°C and then coated using chitosan (0.5 w/v%) in order to increase their adsorption capacity. The removal of CO2 in biogas was achieved about ˜83% using 2.5 g of sorbent zeolite (2M)/chitosan dosage for each column, breakthrough time of 30 min, and flow rate of 100 mL/min. Clinoptilolite zeolites with modifications of an acid-alkaline and chitosan (zeolite (2M)/chitosan) are promising sorbents due to the amine groups from chitosan and high surface-volume ratio are one of important factors in a simultaneous absorption-adsorption method.

  15. 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.

  16. Characterization of the physico-chemical properties of polymeric materials for aerospace flight. [differential thermal and atomic absorption spectroscopic analysis of nickel cadmium batteries

    Science.gov (United States)

    Rock, M.

    1981-01-01

    Electrodes and electrolytes of nickel cadmium sealed batteries were analyzed. Different thermal analysis of negative and positive battery electrodes was conducted and the temperature ranges of occurrence of endotherms indicating decomposition of cadmium hydroxide and nickel hydroxide are identified. Atomic absorption spectroscopy was used to analyze electrodes and electrolytes for traces of nickel, cadmium, cobalt, and potassium. Calibration curves and data are given for each sample analyzed. Instrumentation and analytical procedures used for each method are described.

  17. Determination of Mecruy at Trace Level in Natural Water Samples by Hydride Generation Atomic Absorption Spectrophotometry after Cloud Point Extraction Preconcentration

    Institute of Scientific and Technical Information of China (English)

    Ji Ying SONG; Ming HOU; Li Xiang ZHANG

    2006-01-01

    A method for the determination of trace mercury in water samples by hydride generation atomic absorption spectrophotometry after cloud point extraction was proposed in the present work.The effects of pH, concentration of surfactant, and equilibration time on cloud point extraction were discussed. The enhancement factor of 20 and the detection limit of 0.039 μg/L were obtained for mercury with relative standard deviation of 4.8% (n = 11).

  18. NARROW Na AND K ABSORPTION LINES TOWARD T TAURI STARS: TRACING THE ATOMIC ENVELOPE OF MOLECULAR CLOUDS

    Energy Technology Data Exchange (ETDEWEB)

    Pascucci, I.; Simon, M. N. [Lunar and Planetary Laboratory, The University of Arizona, Tucson, AZ 85721 (United States); Edwards, S. [Five College Astronomy Department, Smith College, Northampton, MA 01063 (United States); Heyer, M. [Department of Astronomy, University of Massachusetts, Amherst, MA 01003-9305 (United States); Rigliaco, E. [Institute for Astronomy, ETH Zurich, Wolfgang-Pauli-Strasse 27, CH-8093 Zurich (Switzerland); Hillenbrand, L. [Department of Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States); Gorti, U.; Hollenbach, D., E-mail: pascucci@lpl.arizona.edu [SETI Institute, Mountain View, CA 94043 (United States)

    2015-11-20

    We present a detailed analysis of narrow Na i and K i absorption resonance lines toward nearly 40 T Tauri stars in Taurus with the goal of clarifying their origin. The Na i λ5889.95 line is detected toward all but one source, while the weaker K i λ7698.96 line is detected in about two-thirds of the sample. The similarity in their peak centroids and the significant positive correlation between their equivalent widths demonstrate that these transitions trace the same atomic gas. The absorption lines are present toward both disk and diskless young stellar objects, which excludes cold gas within the circumstellar disk as the absorbing material. A comparison of Na i and CO detections and peak centroids demonstrates that the atomic gas and molecular gas are not co-located, the atomic gas being more extended than the molecular gas. The width of the atomic lines corroborates this finding and points to atomic gas about an order of magnitude warmer than the molecular gas. The distribution of Na i radial velocities shows a clear spatial gradient along the length of the Taurus molecular cloud filaments. This suggests that absorption is associated with the Taurus molecular cloud. Assuming that the gradient is due to cloud rotation, the rotation of the atomic gas is consistent with differential galactic rotation, whereas the rotation of the molecular gas, although with the same rotation axis, is retrograde. Our analysis shows that narrow Na i and K i absorption resonance lines are useful tracers of the atomic envelope of molecular clouds. In line with recent findings from giant molecular clouds, our results demonstrate that the velocity fields of the atomic and molecular gas are misaligned. The angular momentum of a molecular cloud is not simply inherited from the rotating Galactic disk from which it formed but may be redistributed by cloud–cloud interactions.

  19. 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)

  20. 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.

  1. Synthesis Method and Absorption Application of Nanocrystalline Alloy Flakes

    Institute of Scientific and Technical Information of China (English)

    Pei-Heng Zhou; Long-Jiang Deng

    2007-01-01

    The soft magnetic FeSiB nanocrystalline/amorphous flakes were fabricated by ball milling from the elemental powders and annealing the amorphous precursor, respectively. The microstructure, magnetic and microwave properties were evaluated by different synthesis methods. By computation, ballmilled Fe78Si13B9 flakes demonstrated potential application in absorption.

  2. 原子吸收法测定化探样中的微量汞%Determination of Trace Mercury in Geochemical Samples by Cold Atomic Absorption Spectroscopy

    Institute of Scientific and Technical Information of China (English)

    王茹

    2014-01-01

    化探样品中微量汞的测定多采用原子荧光法,采用冷原子吸收法测汞也有报道。本法用简易吸收装置于 GGX-2型原子吸收光谱仪上,进行化探样品中微量汞的冷原子吸收法测定,测定结果表明,汞的含量在(0.01~2)×10-6范围呈线性,经对省Ⅱ级标样36号、38号进行实验,相对标准偏差分别为10.56%和17.83%,可满足化探要求。%Trace mercury in geochemical samples is normally determined by atomic fluorescence method. There also are reports on determination of trace mercury in geochemical samples by cold atomic absorption spectroscopy. The method is to install simple absorption equipment on GGX-2 atomic absorption spectrometer to determine trace mercury in geochemical samples. The results show that, the content of mercury is linear in the range of (0.01~2)× 10-6. Provincial level Ⅱ sample No. 36 and No. 38 are determined with the cold atomic absorption spectroscopy, relative standard deviations are 10.56% and 17.83% respectively, so the method can meet the requirements of geochemical exploration.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. Determination of gold, indium, tellurium and thallium in the same sample digest of geological materials by atomic-absorption spectroscopy and two-step solvent extraction

    Science.gov (United States)

    Hubert, A.E.; Chao, T.T.

    1985-01-01

    A rock, soil, or stream-sediment sample is decomposed with hydrofluoric acid, aqua regia, and hydrobromic acid-bromine solution. Gold, thallium, indium and tellurium are separated and concentrated from the sample digest by a two-step MIBK extraction at two concentrations of hydrobromic add. Gold and thallium are first extracted from 0.1M hydrobromic acid medium, then indium and tellurium are extracted from 3M hydrobromic acid in the presence of ascorbic acid to eliminate iron interference. The elements are then determined by flame atomic-absorption spectrophotometry. The two-step solvent extraction can also be used in conjunction with electrothermal atomic-absorption methods to lower the detection limits for all four metals in geological materials. ?? 1985.

  11. 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.

  12. 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.

  13. 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…

  14. 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…

  15. 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.

  16. 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

  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

    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.

  18. 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.

  19. 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.

  20. 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.)

  1. 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.

  2. 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.

  3. [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.

  4. 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.

  5. New Atomic Methods for Dark Matter Detection

    Science.gov (United States)

    Roberts, Benjamin; Stadnik, Yevgeny; Dzuba, Vladimir; Flambaum, Victor; Leefer, Nathan; Budker, Dmitry

    2015-05-01

    We propose to exploit P and T violating effects in atoms, nuclei, and molecules to search for dark matter (eg axions) and various other cosmic fields. We perform calculations of electric dipole moments (EDMs) that a dark matter field would induce in atoms. Crucially, the effects we consider here are linear in the small parameter that quantifies the dark matter interaction strength; most current searches rely on effects that are at least quadratic in this parameter. The induced oscillating EDMs have the potential to be measured with very high accuracy, and experimental techniques in this field are evolving fast. Pairs of closely spaced opposite parity levels that are found in diatomic molecules will also lead to a significant enhancement in these effects. We are also interested in a possible explanation for the anomalous DAMA dark matter detection results based on DM-electron scattering. Our calculations may provide a possible mechanism for dark matter induced ionisation modulations that are not ruled out by other experiments. Alternatively, they could further reduce the available parameter space for certain dark matter models.

  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. Drug absorption efficiency in Caenorhbditis elegans delivered by different methods.

    Directory of Open Access Journals (Sweden)

    Shan-Qing Zheng

    Full Text Available BACKGROUND: Caenorhbditis elegans has being vigorously used as a model organism in many research fields and often accompanied by administrating with various drugs. The methods of delivering drugs to worms are varied from one study to another, which make difficult in comparing results between studies. METHODOLOGY/PRINCIPAL FINDINGS: We evaluated the drug absorption efficiency in C. elegans using five frequently used methods with resveratrol with low aqueous solubility and water-soluble 5-Fluoro-2'-deoxyuridine (FUDR as positive compounds. The drugs were either applied to the LB medium with bacteria OP50, before spreading onto Nematode Growth Medium (NGM plates (LB medium method, or to the NGM with live (NGM live method or dead bacteria (NGM dead method, or spotting the drug solution to the surface of plates directly (spot dead method, or growing the worms in liquid medium (liquid growing method. The concentration of resveratrol and FUDR increased gradually within C. elegans and reached the highest during 12 hours to one day and then decreased slowly. At the same time point, the higher the drug concentration, the higher the metabolism rate. The drug concentrations in worms fed with dead bacteria were higher than with live bacteria at the same time point. Consistently, the drug concentration in medium with live bacteria decreased much faster than in medium with dead bacteria, reach to about half of the original concentration within 12 hours. CONCLUSION: Resveratrol with low aqueous solubility and water-soluble FUDR have the same absorption and metabolism pattern. The drug metabolism rate in worms was both dosage and time dependent. NGM dead method and liquid growing method achieved the best absorption efficiency in worms. The drug concentration within worms was comparable with that in mice, providing a bridge for dose translation from worms to mammals.

  8. A Method for Finding Metabolic Pathways Using Atomic Group Tracking

    Science.gov (United States)

    Zhong, Cheng; Lin, Hai Xiang; Wang, Jianyi

    2017-01-01

    A fundamental computational problem in metabolic engineering is to find pathways between compounds. Pathfinding methods using atom tracking have been widely used to find biochemically relevant pathways. However, these methods require the user to define the atoms to be tracked. This may lead to failing to predict the pathways that do not conserve the user-defined atoms. In this work, we propose a pathfinding method called AGPathFinder to find biochemically relevant metabolic pathways between two given compounds. In AGPathFinder, we find alternative pathways by tracking the movement of atomic groups through metabolic networks and use combined information of reaction thermodynamics and compound similarity to guide the search towards more feasible pathways and better performance. The experimental results show that atomic group tracking enables our method to find pathways without the need of defining the atoms to be tracked, avoid hub metabolites, and obtain biochemically meaningful pathways. Our results also demonstrate that atomic group tracking, when incorporated with combined information of reaction thermodynamics and compound similarity, improves the quality of the found pathways. In most cases, the average compound inclusion accuracy and reaction inclusion accuracy for the top resulting pathways of our method are around 0.90 and 0.70, respectively, which are better than those of the existing methods. Additionally, AGPathFinder provides the information of thermodynamic feasibility and compound similarity for the resulting pathways. PMID:28068354

  9. [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.

  10. Determination of mercury by cold vapor atomic absorption spectrophotometer in Tongkat Ali preparations obtained in Malaysia.

    Science.gov (United States)

    Ang, Hooi-Hoon; Lee, Ee-Lin; Cheang, Hui-Seong

    2004-01-01

    The DCA (Drug Control Authority), Malaysia, has implemented the phase 3 registration of traditional medicines on 1 January 1992, with special emphasis on the quality, efficacy, and safety (including the presence of heavy metals) in all pharmaceutical dosage forms of traditional medicine preparations. As such, a total of 100 products in various pharmaceutical dosage forms of a herbal preparation, containing Tongkat Ali, were analyzed for mercury content using cold vapor atomic absorption spectrophotometer. Results showed that 36% of the above products possessed 0.52 to 5.30 ppm of mercury and, therefore, do not comply with the quality requirement for traditional medicines in Malaysia. Out of these 36 products, 5 products that possessed 1.05 to 4.41 ppm of mercury were in fact have already registered with the DCA, Malaysia. However, the rest of the products that contain 0.52 to 5.30 ppm of mercury still have not registered with the DCA, Malaysia. Although this study showed that only 64% of the products complied with the quality requirement for traditional medicines in Malaysia pertaining to mercury, they cannot be assumed safe from mercury contamination because of batch-to-batch inconsistency.

  11. Use of atomic absorption spectrometry in assessment of biomonitor plants for lead, cadmium and copper pollution.

    Science.gov (United States)

    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 x kg(-1), respectively. Significantly increased lead concentration up to 2 750 mg x 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 angusti folia 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. Comparative study of heavy metals in dried and fluid milk in Peshawar by atomic absorption spectrophotometry.

    Science.gov (United States)

    Lutfullah, Ghosia; Khan, Abid Ali; Amjad, Azra Yasmeen; Perveen, Sajida

    2014-01-01

    Various essential and toxic heavy metals (Ca, Mg, Cu, Zn, Fe, Mn, Pb, Cd, Cr, and Ni) contents in various types of dried (infant formula and powdered) and fluid (fresh and processed) cow milk were assessed by atomic absorption spectrophotometry. The milk samples were collected from local markets of different parts of Peshawar city, Pakistan. Heavy metal concentrations varied significantly depending upon the type of milk. The heavy metal concentrations in most of the samples were within normal and permissible ranges. It was observed that the samples contained considerable amounts of calcium, while magnesium levels were well above the required levels. The results also revealed that copper levels were slightly lower than the permissible limits. The concentration of zinc in dried milk samples was greater than the values for the liquid milk types. Infant milk formulae had higher iron levels as compared to other milk samples because of the added constituents. Significant differences were observed in the mean values of manganese and cadmium in different types of milk. The toxic metals were within the acceptable limits and did not show significant levels leading to toxicity.

  13. 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.

  14. 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.

  15. Comparative Study of Heavy Metals in Dried and Fluid Milk in Peshawar by Atomic Absorption Spectrophotometry

    Science.gov (United States)

    Lutfullah, Ghosia; Khan, Abid Ali; Amjad, Azra Yasmeen; Perveen, Sajida

    2014-01-01

    Various essential and toxic heavy metals (Ca, Mg, Cu, Zn, Fe, Mn, Pb, Cd, Cr, and Ni) contents in various types of dried (infant formula and powdered) and fluid (fresh and processed) cow milk were assessed by atomic absorption spectrophotometry. The milk samples were collected from local markets of different parts of Peshawar city, Pakistan. Heavy metal concentrations varied significantly depending upon the type of milk. The heavy metal concentrations in most of the samples were within normal and permissible ranges. It was observed that the samples contained considerable amounts of calcium, while magnesium levels were well above the required levels. The results also revealed that copper levels were slightly lower than the permissible limits. The concentration of zinc in dried milk samples was greater than the values for the liquid milk types. Infant milk formulae had higher iron levels as compared to other milk samples because of the added constituents. Significant differences were observed in the mean values of manganese and cadmium in different types of milk. The toxic metals were within the acceptable limits and did not show significant levels leading to toxicity. PMID:24967439

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. A detailed study of thermal decomposition, amalgamation/ atomic absorption spectrophotometry methodology for the quantitative analysis of mercury in fish and hair.

    Science.gov (United States)

    Butala, Steven J M; Scanlan, Larry P; Chaudhuri, Sanwat N

    2006-11-01

    The analytical method for determining the concentration of mercury in fish by thermal decomposition, amalgamation/ atomic absorption spectrophotometry was thoroughly studied. Specific issues addressed were accurate modeling of instrumental response, the use of quartz and nickel boats, carryover effects, software limitations, and troubleshooting. The DMA-80 Direct Mercury Analyzer instrument was calibrated using a total of 22 points, and the resultant curves statistically analyzed. At minimum, second-order polynomials were required to adequately model the data. TORT-2 standard reference material was analyzed in both quartz and nickel boats and found to give equivalent performance in both types of vessels and well within the 95% confidence interval. DOLT-3 standard reference material also yielded values well within the 95% confidence interval, but the DORM-2 standard reference material did not. Carryover effects were found to be minimal with a new catalyst tube but increased with catalyst age. Blanks should be run after the analysis of high mercury content samples; however, when the catalyst has aged, two blanks are required to reduce apparent mercury signals to nominal blank values. Comparable results between thermal decomposition, amalgamation/atomic absorption spectrophotometry and cold-vapor atomic absorption spectrophotometry were demonstrated. The feasibility of using this instrument to analyze hair was also explored and found to be suitable. Software problems and limitations have been noted when attempting to implement a high-throughput methodology. Instrumental drift was found to be minimal when operated over long periods. Blank values can provide important diagnostic indicators.

  2. Solid Phase Extraction and Determination of Nickel in Water Samples by Using Novel Thiol-Containing Sulfonamide Polymeric Resin and Atomic Absorption Spectrophotometer

    Institute of Scientific and Technical Information of China (English)

    Nagihan M Karaaslan; B Filiz Senkal; Cigdem Er; Halim Avci; Mehmet Yaman

    2011-01-01

    Interest in preconcentration techniques for the determination of metals at ultratrace levels still continues increasingly because of some disadvantages of flameless atomic absorption spectrometry as well as the high costs of other sensitive methods in compared to flame atomic absorption spectrometry.In this study,thiol-containing sulfonamide resin was synthesized,characterized and applied as a new sorption material for solid phase extraction of nickel in drinking water samples.After preconcentration procedure,flame atomic absorption spectrometry was used for determinations.Optimum parameters were found to be pH=3.2,contact time =20 min and eluate volume=3 mL.The limit of detection was found to be 0.75 ng · mL-1.The synthesized resin exhibits the superiority in compared to the other adsorption reagents because of the fact that there is no necessity of any complexing reagent,high sorption capacity as well as the relatively fast extraction rate.The Ni concentrations in the studied 21 kind of water samples were found to be in the range of BDL-4.0 ng ·mL-1.

  3. 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

  4. 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

  5. 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

    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...... with an aqueous solution of 6 mmol L-1 of salicylate ion at pH 8.5 as the mobile phase which allowed the isocratic separation of the four selenium analytes within 8 minutes. The separated selenium species were detected on-line by flame atomic absorption spectrometry (FAAS) or inductively coupled plasma mass...... 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...

  6. Validation of an analytical method for the determination of total mercury in urine samples using cold vapor atomic absorption spectrometry (CV-AAS); Validacao de metodologia analitica para determinacao de mercurio total em amostras de urina para espectrometria de absorcao atomica com geracao de vapor frio (CV-AAS)

    Energy Technology Data Exchange (ETDEWEB)

    Guilhen, Sabine Neusatz

    2009-07-01

    Mercury (Hg) is a toxic metal applied to a variety of products and processes, representing a risk to the health of occupationally or accidentally exposed subjects. Dental amalgam is a restorative material composed of metallic mercury, which use has been widely debated in the last decades. Due to the dubiety of the studies concerning dental amalgam, many efforts concerning this issue have been conducted. The Tropical Medicine Foundation (Tocantins, Brazil) has recently initiated a study to evaluate the environmental and occupational levels of exposure to mercury in dentistry attendants at public consulting rooms in the city of Araguaina (TO). In collaboration with this study, the laboratory of analysis at IPEN's Chemistry and Environment Center is undertaking the analysis of mercury levels in exposed subjects' urine samples using cold vapor atomic absorption spectrometry. This analysis requires the definition of a methodology capable of generating reliable results. Such methodology can only be implemented after a rigorous validation procedure. As part of this work, a series of tests were conducted in order to confirm the suitability of the selected methodology and to assert that the laboratory addresses all requirements needed for a successful implementation of the methodology. The following parameters were considered in order to test the method's performance: detection and quantitation limits, selectivity, sensitivity, linearity, accuracy and precision. The assays were carried out with certified reference material, which assures the traceability of the results. Taking into account the estimated parameters, the method can be considered suitable for the afore mentioned purpose. The mercury concentration found for the reference material was of (95,12 +- 11,70)mug.L{sup -1} with a recovery rate of 97%. The method was also applied to 39 urine samples, six of which (15%) showing urinary mercury levels above the normal limit of 10{mu}g.L{sup -1}. The

  7. 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.

  8. Electrothermal atomic absorption spectrometric determination of cobalt, copper, lead and nickel traces in aragonite following flotation and extraction separation.

    Science.gov (United States)

    Zendelovska, D; Pavlovska, G; Cundeva, K; Stafilov, T

    2001-03-30

    A method of determination of Co, Cu, Pb and Ni in nanogram quantities from aragonite is presented. Flotation and extraction of Co, Cu, Pb and Ni is suggested as methods for elimination matrix interferences of calcium. The method of flotation is performed by iron(III) hexamethylenedithiocarbamate, Fe(HMDTC)(3), as a colloid precipitate collector. The liquid-liquid extraction of Co, Cu, Pb and Ni is carried out by sodium diethyldithiocarbamate, NaDDTC, as complexing reagent into methylisobutyl ketone, MIBK. The electrothermal atomic absorption spectrometry (ETAAS) is used for determination of analytes. The detection limits of ETAAS followed by flotation are: 7.8 ng.g(-1) for Co, 17.1 ng.g(-1) for Cu, 7.2 ng.g(-1) for Pb and 9.0 mug.g(-1) for Ni. The detection limits of ETAAS followed by extraction are found to be: 12.0 ng.g(-1) for Co, 51.0 ng.g(-1) for Cu, 24.0 ng.g(-1) for Pb and 21.0 ng.g(-1) for Ni.

  9. 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.

  10. 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.

  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. 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).

  13. 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.

  14. [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.

  15. 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.

  16. 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.

  17. Detecting Neutral Atoms on an Atom Chip

    OpenAIRE

    Wilzbach, M.; Haase, A.; Schwarz, M; Heine, D.; Wicker, K.; Liu, X; Brenner, K. -H.; Groth, S.; Fernholz, Th.; Hessmo, B.; Schmiedmayer, J.

    2006-01-01

    Detecting single atoms (qubits) is a key requirement for implementing quantum information processing on an atom chip. The detector should ideally be integrated on the chip. Here we present and compare different methods capable of detecting neutral atoms on an atom chip. After a short introduction to fluorescence and absorption detection we discuss cavity enhanced detection of single atoms. In particular we concentrate on optical fiber based detectors such as fiber cavities and tapered fiber d...

  18. 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.

  19. Method and apparatus for enhancing laser absorption sensitivity

    Science.gov (United States)

    Webster, Christopher R. (Inventor)

    1987-01-01

    A simple optomechanical method and apparatus is described for substantially reducing the amplitude of unwanted multiple interference fringes which often limit the sensitivities of tunable laser absorption spectrometers. An exterior cavity is defined by partially transmissible surfaces such as a laser exit plate, a detector input, etc. That cavity is spoiled by placing an oscillating plate in the laser beam. For tunable diode laser spectroscopy in the mid-infrared region, a Brewster-plate spoiler allows the harmonic detection of absorptances of less than 10 to the -5 in a single laser scan. Improved operation is achieved without subtraction techniques, without complex laser frequency modulation, and without distortion of the molecular lineshape signal. The technique is applicable to tunable lasers operating from UV to IR wavelengths and in spectrometers which employ either short or long pathlengths, including the use of retroreflectors or multipass cells.

  20. Validation of an analytical method for the determination of total mercury in urine samples using cold vapor atomic absorption spectrometry (CV-AAS); Validacao de metodologia analitica para determinacao de mercurio total em amostras de urina por espectrometria de absorcao atomica com geracao de vapor frio (CV-AAS)

    Energy Technology Data Exchange (ETDEWEB)

    Guilhen, Sabine Neusatz

    2009-07-01

    Mercury (Hg) is a toxic metal applied to a variety of products and processes, representing a risk to the health of occupationally or accidentally exposed subjects. Dental amalgam is a restorative material composed of metallic mercury, which use has been widely debated in the last decades. Due to the dubiety of the studies concerning dental amalgam, many efforts concerning this issue have been conducted. The Tropical Medicine Foundation (Tocantins, Brazil) has recently initiated a study to evaluate the environmental and occupational levels of exposure to mercury in dentistry attendants at public consulting rooms in the city of Araguaina (TO). In collaboration with this study, the laboratory of analysis at IPEN's Chemistry and Environment Center is undertaking the analysis of mercury levels in exposed subjects' urine samples using cold vapor atomic absorption spectrometry. This analysis requires the definition of a methodology capable of generating reliable results. Such methodology can only be implemented after a rigorous validation procedure. As part of this work, a series of tests were conducted in order to confirm the suitability of the selected methodology and to assert that the laboratory addresses all requirements needed for a successful implementation of the methodology. The following parameters were considered in order to test the method’s performance: detection and quantitation limits, selectivity, sensitivity, linearity, accuracy and precision. The assays were carried out with certified reference material, which assures the traceability of the results. Taking into account the estimated parameters, the method can be considered suitable for the afore mentioned purpose. The mercury concentration found for the reference material was of (95,12 ± 11,70)μg.L{sup -1} with a recovery rate of 97%. The method was also applied to 39 urine samples, six of which (15%) showing urinary mercury levels above the normal limit of 10μg.L{sup −1}. The obtained

  1. Graphite furnace and hydride generation atomic absorption spectrometric determination of cadmium, lead, and tin traces in natural surface waters: study of preconcentration technique performance.

    Science.gov (United States)

    Tsogas, George Z; Giokas, Dimosthenis L; Vlessidis, Athanasios G

    2009-04-30

    In this study three major types of preconcentration methods based upon different principles (cation exchange, physical absorption and hydrophobic extraction) were evaluated and optimized for the extraction and determination of three highly toxic heavy metals namely Cd, Pb and Sn by graphite furnace and hybrid generation atomic absorption spectrometry in real samples. The optimum analytical conditions were examined and the analytical features of each method were revealed and compared. Detection limits as low as 0.003-0.025 microg L(-1) for Cd(2+), 0.05-0.10 microg L(-1) for Pb(2+) and 0.1-0.25 microg L(-1) for Sn(4+) depending on the extraction method were obtained with RSD values between 3.08% and 6.11%. A preliminary assessment of the pollution status of three important natural ecosystems in Epirus region (NW Greece) was performed and some early conclusions were drawn and discussed.

  2. Continuous Determination of Heavy Metals in Water by Atomic Fluorescence and Atomic Absorption Spectrometry%原子荧光和原子吸收法连续测定水中的重金属

    Institute of Scientific and Technical Information of China (English)

    谢倩

    2015-01-01

    通过剖析原子荧光和原子吸收法的不同消解体系,优化实验条件,确定了原子荧光和原子吸收法连续测定水中的硒、砷、锌、铜的含量的最佳消解条件和最佳仪器测定条件。经加标回收以及标样分析,连续测定的灵敏度高,回收率在95.9%~109%之间,相对标准误差低于4.41%,操作简便快速,结果精确。%By analyzing the different digestion system of atomic fluorescence and atomic absorption method and optimizing experimental conditions, the optimal digestion conditions and the best measurement conditions of instruments for continuous determination selenium, arsenic, zinc, copper content in water by atomic fluorescence and atomic absorption spectrometry were determined.Spiking recovery and standard analysis result showed that continuous measurement had high sensitivity, and the recoveries was between 95.9% and 109%, relative standard deviation was less than 4.41%, the operation was simple, rapid and accurate.

  3. Effective atomic numbers of some tissue substitutes by different methods: A comparative study.

    Science.gov (United States)

    Singh, Vishwanath P; Badiger, N M

    2014-01-01

    Effective atomic numbers of some human organ tissue substitutes such as polyethylene terephthalate, red articulation wax, paraffin 1, paraffin 2, bolus, pitch, polyphenylene sulfide, polysulfone, polyvinylchloride, and modeling clay have been calculated by four different methods like Auto-Zeff, direct, interpolation, and power law. It was found that the effective atomic numbers computed by Auto-Zeff, direct and interpolation methods were in good agreement for intermediate energy region (0.1 MeV numbers by direct method and Auto-Zeff was observed in photo-electric and pair-production regions. Effective atomic numbers computed by power law were found to be close to direct method in photo-electric absorption region. The Auto-Zeff, direct and interpolation methods were found to be in good agreement for computation of effective atomic numbers in intermediate energy region (100 keV numbers in photo-electric region (10 keV number mentioned in the present study. An accurate estimation of Rayleigh scattering is required to eliminate effect of molecular, chemical, or crystalline environment of the atom for estimation of gamma interaction parameters.

  4. 40 CFR Appendix D to Part 136 - Precision and Recovery Statements for Methods for Measuring Metals

    Science.gov (United States)

    2010-07-01

    ..., Analyses for Trace Methods in Water by Atomic Absorption Spectroscopy (Direct Aspiration) and Colorimetry... in Water by Atomic Absorption Spectroscopy (Direct Aspiration) and Colorimetry”; National Technical... Study 7, Analyses for Trace Methods in Water by Atomic Absorption Spectroscopy (Direct Aspiration)...

  5. 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.

  6. 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

  7. 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.

  8. 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.

  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. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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%.

  15. Determination of traces of Mo in soils and geological materials by solvent extraction of the molybdenum-thiocyanate complex and atomic absorption.

    Science.gov (United States)

    Kim, C H; Owens, C M; Smythe, L E

    1974-06-01

    Comprehensive studies of the extraction of the molybdenum-thiocyanate complex with methyl isobutyl ketone have resulted in an improved method for the determination of traces of molybdenum in soils and geological materials by atomic-absorption spectroscopy. The method is applicable in the range 1-500 ppm Mo, with 1-g samples, giving relative standard deviations not exceeding about 8% at a level of 1 ppm. The limit of detection is 0.1 ppm. There are few interferences, and large quantities of iron are without effect.

  16. 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.

  17. Chemical modifiers in arsenic determination in biological materials by tungsten coil electrothermal atomic absorption spectrometry.

    Science.gov (United States)

    Bruhn, C G; Huerta, V N; Neira, J Y

    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 microg) and Rh (2.0 microg) modifiers and in the digest solutions of the study matrices, Rh (2.0 microg) was more effective modifier and was selected as such. The mean within-day repeatability was 2.8% in consecutive measurements (25-100 microg L(-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 sigmablank/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 (Erel%) 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(-1)), reliable, of low cost, and was applied to the determination of As in hair samples of exposed and unexposed workers.

  18. 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.)

  19. Validação de metodologia analítica para determinação de mercúrio total em amostras de urina por espectrometria de absorção atômica com geração de vapor frio (CV-AAS: estudo de caso Validation of an analytical method for the determination of total mercury in urine samples using cold vapor atomic absorption spectrometry (CV-AAS: case study

    Directory of Open Access Journals (Sweden)

    Sabine Neusatz Guilhen

    2010-01-01

    Full Text Available Mercury is a toxic metal used in a variety of substances over the course history. One of its more dubious uses is in dental amalgam restorations. It is possible to measure very small concentrations of this metal in the urine of exposed subjects by the cold vapor atomic absorption technique. The present work features the validation as an essential tool to confirm the suitability of the analytical method chosen to accomplish such determination. An initial analysis will be carried out in order to evaluate the environmental and occupational levels of exposure to mercury in 39 members of the auxiliary dental staff at public consulting rooms in the city of Araguaína (TO.

  20. Analysis of the uncertainty in the determination of the lead in human urine by graphite furnace atomic absorption spectrographic method%石墨炉原子吸收光谱法测定尿铅的不确定度分析

    Institute of Scientific and Technical Information of China (English)

    刘灵辉; 谷素英; 曾细嫦; 卓盈

    2009-01-01

    目的 分析石墨炉原子吸收光谱法测定尿铅过程中不确定度的主要来源,找出关键的影响因素,为实验室质量控制提供一定的理论依据.方法 采用石墨炉原子吸收光谱法测定尿液中铅的浓度,同时构建数学模型,对各部分分量进行分析.结果 对于尿样中铅浓度为25.15 μg/ml的样品,取包含因子k=2,其扩展不确定度为1.2 μg/ml,最终报告尿铅含量(334.5±12.0) μg/L;同时对影响测定结果 的不确定度的各部分因素进行了量化,标准储备液及稀释校准过程引入的不确定度U(sta)为5.13×10-3;样品制备过程引入的不确定度u (pre)为4.56×10-3;标准曲线拟和引入的不确定度U(Co)为0.018 7;重复条件下的标准偏差u(-ω)为3.60×10-3.结论 影响尿铅测定结果 不确定度的主要因素是工作曲线拟合引入的误差.%Objective Analysis of the uncertainty in the measurement of lead in human urine by graphite furnace atomic absorption spectrometer was intreduced in this article.The sources of uncertainty and their effects on the total uneertainty were also analyzed.Methods Construct the mathematical model for evaluation of uncertainty in measurement based on a comprehensive understanding of the whole procedure of the determination.Results The measurement result of lead in human urine was given as (334.5±12.0)μg/L.Conclusions The major factor in influence on the determination of lead in human urine was the working curve fitting introduction error.

  1. 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.

  2. Analytical method for promoting process capability of shock absorption steel

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Mechanical properties and low cycle fatigue are two factors that must be considered in developing new type steel for shock absorption. Process capability and process control are significant factors in achieving the purpose of research and development programs. Often-used evaluation methods failed to measure process yield and process centering; so this paper uses Taguchi loss function as basis to establish an evaluation method and the steps for assessing the quality of mechanical properties and process control of an iron and steel manufacturer. The establishment of this method can serve the research and development and manufacturing industry and lay a foundation in enhancing its process control ability to select better manufacturing processes that are more reliable than decision making by using the other commonly used methods.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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

  8. 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

  9. Preconcentration of Co, Ni, Cd and Zn on naphthalene–2,4,6-trimorpholino-1,3,5-triazin adsorbent and flame atomic absorption determination

    Directory of Open Access Journals (Sweden)

    TAYYEBEH MADRAKIAN

    2010-05-01

    Full Text Available A preconcentration method was developed for the determination of trace amounts of Co, Ni, Cd and Zn by atomic absorption spectrometry. The method is based on the retention of the metal cations by naphthalene–2,4,6-trimorpholino-1,3,5-triazin adsorbent in a column. The adsorbed metals were then eluted from the column with hydrochloric acid and the Co, Ni, Cd and Zn were determined by flame atomic absorption spectrometry. The optimal extraction and elution conditions were studied. The effects of diverse ions on the preconcentration were also investigated. A preconcentration factor of 250 for Co(II, Ni(II and Zn(II, and 400 for Cd(II can easily be achieved. Calibration graphs were obtained and the detection limits of the method for Co(II, Ni(II, Cd(II and Zn(II were 0.51, 0.49, 0.17 and 0.10 ng mL-1, respectively. The relative standard deviations (RSD of 0.37–2.31 % for Co, 0.37–3.73 % for Ni, 2.20–2.40 % for Cd and 1.50–2.56 % for Zn were obtained. The method was also used for the simultaneous preconcentration of these elements and the method was successfully applied to their preconcentration and determination. The method was applied to the determination of Co, Ni, Cd and Zn in several real samples.

  10. 原子吸收光谱法测定食品中重金属元素的研究进展%Research Progress of Heavy Metals in Foods by Atomic Absorption Spectrometry

    Institute of Scientific and Technical Information of China (English)

    帅瑾; 巩卫东; 刘胜男; 卫星; 张国庆

    2014-01-01

    近年来,原子吸收光谱法广泛用于食品中重金属含量的检测,该法具有检出限低、准确度高、选择性好及分析速度快等特点。本文综述了使用石墨炉原子吸收、火焰原子吸收和氢化物发生原子吸收3种原子吸收法测定粮食、蔬菜、水果和海产品中的铅、镉、铬、砷和汞等重金属元素的研究进展。此外,对原子吸收法在食品检测中的应用进行展望。%Atomic absorption spectrometry is widely used in detection of heavy metals in foods in recent years, which has low detection limit, high accuracy, good selectivity, fast analysis speed and so on. In this article, research advance in determination of heavy metals such as lead, cadmium, chromium, mercury and arsenic in cereals, vegeta-bles, fruits and seafoods were summarized by graphite furnace atomic absorption spectrometry, flame atomic absorption spectrometry and hydride generation atomic absorption spectrometry. In addition, application of atomic absorption method in food detection were prospected.

  11. 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.

  12. Method for laser spectroscopy of metastable pionic helium atoms

    Energy Technology Data Exchange (ETDEWEB)

    Hori, M., E-mail: Masaki.Hori@mpq.mpg.de; Sótér, A.; Aghai-Khozani, H. [Max-Planck-Institut für Quantenoptik (Germany); Barna, D. [CERN (Switzerland); Dax, A. [Paul Scherrer Institut (Switzerland); Hayano, R. S.; Murakami, Y.; Yamada, H. [University of Tokyo, Department of Physics (Japan)

    2015-08-15

    The PiHe collaboration is currently attempting to carry out laser spectroscopy of metastable pionic helium atoms using the high-intensity π{sup −} beam of the ring cyclotron facility of the Paul Scherrer Institute. These atoms are heretofore hypothetical three-body Coulomb systems each composed of a helium nucleus, a π{sup −} occupying a Rydberg state, and an electron occupying the 1s ground state. We briefly review the proposed method by which we intend to detect the laser spectroscopic signal. This complements our experiments on metastable antiprotonic helium atoms at CERN.

  13. A liquid drop model for embedded atom method cluster energies

    Science.gov (United States)

    Finley, C. W.; Abel, P. B.; Ferrante, J.

    1996-01-01

    Minimum energy configurations for homonuclear clusters containing from two to twenty-two atoms of six metals, Ag, Au, Cu, Ni, Pd, and Pt have been calculated using the Embedded Atom Method (EAM). The average energy per atom as a function of cluster size has been fit to a liquid drop model, giving estimates of the surface and curvature energies. The liquid drop model gives a good representation of the relationship between average energy and cluster size. As a test the resulting surface energies are compared to EAM surface energy calculations for various low-index crystal faces with reasonable agreement.

  14. Determination of cobalt in biological samples by electrothermal atomic absorption spectrometry after extraction with 1,5-bis (di-2-pyridylmethylene) thiocarbohydrazide

    Energy Technology Data Exchange (ETDEWEB)

    Collado, G.; Bosch Ojeda, C.; Garcia de Torres, A.; Cano Pavon, J.M. [University of Malaga (Spain)

    1995-06-01

    A method for the determination of trace amounts of cobalt in biological samples by atomic absorption spectrometry with graphite furnace atomization extraction conditions were evaluated from a critical study of the effects of pH, concentration of extractant, shaking time and ionic strength. The detection limit for cobalt is 0.06 ng ml{sup -1} and the calibration is linear from 0.1 to 2.5 ng ml{sup -1}. The relative standard deviation for ten replicate measurements is 1.7 % for 0.5 ng ml{sup -1} of cobalt. The effect of interferences was studied and no interferences from the elements commonly found in biological materials were observed. The chief advantage of the method lies in its maximum allowable aqueous-to-organic phase volume ratio of 30:1. Results from the analysis of some certified biological reference materials are given. (authors). 14 refs., 1 figs., 3 tabs.

  15. Analytical method for promoting process capability of shock absorption steel

    Institute of Scientific and Technical Information of China (English)

    SUNGWen-Pei; SHIHMing-Hsiang; CHENKuen-Suan

    2003-01-01

    Mechanical properties and low cycle fatigue are two factors that must be considered in developin gnew type steel for shock absorption. Process capability and process control are significant factors in achieving the purpose of research and development programs. Often-used evaluation methods failed to measure processyield and process centering ; so this paper uses Taguchi loss function as basis to establish an evaluation methodand the steps for assessing the quality of mechanical properties and process control of an iron and steel manu-facturer. The establishment of this method can serve the research and development and manufacturing industry and lay a foundation in enhancing its process control ability to select better manufacturing processes that are more reliable than decision making by using the other commonly used methods.

  16. 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.

  17. 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.)

  18. 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.

  19. Selective speciation of inorganic antimony on tetraethylenepentamine bonded silica gel column and its determination by graphite furnace atomic absorption spectrometry.

    Science.gov (United States)

    Mendil, Durali; Bardak, Hilmi; Tuzen, Mustafa; Soylak, Mustafa

    2013-03-30

    A speciation system for antimony (III) and antimony (V) ions that based on solid phase extraction on tetraethylenepentamine bonded silica gel has been established. Antimony was determined by graphite furnace atomic absorption spectrometry (GF-AAS). Analytical conditions including pH, sample volume, etc., were studied for the quantitative recoveries of Sb (III) and Sb (V). Matrix effects on the recovery were also investigated. The recovery values and detection limit for antimony (III) at optimal conditions were found as >95% and 0.020 μg L(-1), respectively. Preconcentration factor was calculated as 50. The capacity of adsorption for the tetraethylenepentamine bonded silica gel was 7.9 mg g(-1). The validation was checked by analysis of NIST SRM 1573a Tomato laves and GBW 07605 Tea certified reference materials. The procedure was successfully applied to speciation of antimony in tap water, mineral water and spring water samples. Total antimony was determined in refined salt, unrefined salt, black tea, rice, tuna fish and soil samples after microwave digestion and presented enrichment method combination. Copyright © 2013 Elsevier B.V. All rights reserved.

  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.