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D Diaz M Pace - One of the best experts on this subject based on the ideXlab platform.
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assessment of sorption capability of montmorillonite clay for lead removal from water using laser induced breakdown Spectroscopy and Atomic Absorption Spectroscopy
Microchemical Journal, 2019Co-Authors: E J Teran, Maria Luciana Montes, Corina Iris Rodriguez, L Martino, Maria Angeles Quiroga, R Landa, R Torres M Sanchez, D Diaz M PaceAbstract:Abstract Laser–induced breakdown Spectroscopy (LIBS) and Atomic Absorption Spectroscopy (AAS) techniques were applied for quantitative analysis of the remaining Pb content in water samples after treatment with a raw montmorillonite (MMT) and an organic derivative (MMO) clays for heavy metal removal, an issue of crucial importance for decontamination of water bodies. The Pb sorption capabilities of MMT and MMO clays were assessed by using solutions with known Pb concentrations, in the range 100–500 ppm. To carry out the LIBS analysis, the samples were prepared in the form of solid pellets with powdered calcium hydroxide addition. The measurement conditions were optimized to achieve reliable analytical results and the plasma parameters, i.e., temperature and electron density, were obtained. For quantification purpose, a calibration curve was constructed with the Pb I emission line at 4057.8 A measured at the time window 30–45 μs by using reference samples with Pb concentrations in the range 56–715 ppm. The Pb residual content in the liquid samples determined with LIBS showed a good agreement with those measured with AAS. The sorption efficiency of Pb from contaminated water was calculated through a sorption percentage SPb%. The calculated SPb% was higher for MMT (56%–100%) than for MMO (27%–47%). The results also demonstrated the usefulness of LIBS method for the determination of Pb concentrations in liquid samples.
Guanhua Wang - One of the best experts on this subject based on the ideXlab platform.
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rapid and selective detection of hg ii in water using aunp in situ modified filter paper by a head space solid phase extraction zeeman Atomic Absorption Spectroscopy method
New Journal of Chemistry, 2020Co-Authors: Yongqian Lei, Fang Zhang, Peng Guan, Pengran Guo, Guanhua WangAbstract:In this work, Au nanoparticle (AuNP)-modified filter paper as a highly sensitive mercury extractant was successfully prepared in situ and applied in the head-space solid phase extraction (HS-SPE) of Hg(II) in water. The microstructure of the modified filter paper was characterized by using X-ray diffraction and scanning electron microscopy (XRD/SEM), and the results showed that AuNPs were well distributed on the fiber surface of the filter paper. Combined with portable Zeeman Atomic Absorption Spectroscopy (ZAAS), the modified filter paper was successfully applied to Hg detection in water samples. Specifically, it can easily achieve in situ sample collection and detection under negative pressure in the field, which was reported for the first time. Several influencing factors such as extraction temperature, time, stirring speed, pH value, reductants, inorganic ions, and organic interfering and complexing agents were all investigated thoroughly. The limit of detection (LOD) for Hg(II) was 0.09 μg L−1, with linearity ranging from 0.09 to 50 μg L−1. Good recoveries were also obtained between 82 and 106% with RSDs below 7% in real water samples. The established method provided a convenient route for mercury detection in environmental water with a low amount of sample required (1 mL) and good detection performance, which is comparable to that of ICP-MS.
Ali Akbari Sehat - One of the best experts on this subject based on the ideXlab platform.
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interference free and fast determination of manganese ii iron iii and copper ii ions in different real samples by flame Atomic Absorption Spectroscopy after column graphene oxide based solid phase extraction
Microchemical Journal, 2016Co-Authors: Mohammad Reza Pourjavid, Masoud Arabieh, Seyed Reza Yousefi, Ali Akbari SehatAbstract:Abstract A solid phase extraction (SPE) and flame Atomic Absorption Spectroscopy (FAAS) for the determination of Mn(II), Fe(III) and Cu(II) ions with a graphene oxide (GO) packed column and 1-Phenyl-3-(2-thienylmethyl)thiourea (PTT) as chelating reagent was studied. In theoretical part, the PM6 semi-empirical and PBE density functional theory methods were used for investigation of adsorption mechanism of the complexes on GO sheet. The calculated thermochemistry of the complexation reactions was reported. Based on quantum theory of atoms in molecules (QTAIM) analysis, the nature of the metal/ligand bonding was discussed. Extraction efficiency and the effects of parameters such as flow rate, pH, type and the least amount of acid for stripping of understudied ions from the modified column and break through volume were examined. The preconcentration factor was 280 (for 1400 mL of sample solution and flow rate of 10 mL min− 1) and detection limit of the proposed method was found in the range of 0.06–0.49 μg L− 1. The developed method was successfully applied to the determination of Mn(II), Fe(III) and Cu(II) ions in leaves of spinach, honey, hair, blood and various water samples.
K Niemax - One of the best experts on this subject based on the ideXlab platform.
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element selective detection of molecular species applying chromatographic techniques and diode laser Atomic Absorption spectrometry
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2004Co-Authors: M Miclea, K Kunze, Alexander Zybin, Joachim Koch, Joachim Franzke, K NiemaxAbstract:Tunable diode laser Atomic Absorption Spectroscopy (DLAAS) combined with separation techniques and atomization in plasmas and flames is presented as a powerful method for analysis of molecular species. The analytical figures of merit of the technique are demonstrated by the measurement of Cr(VI) and Mn compounds, as well as molecular species including halogen atoms, hydrogen, carbon and sulfur.
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characterization of a high pressure microdischarge using diode laser Atomic Absorption Spectroscopy
Plasma Sources Science and Technology, 2002Co-Authors: C Penache, M Miclea, A Brauningdemian, O Hohn, S Schossler, T Jahnke, K Niemax, H SchmidtbockingAbstract:A high-pressure dc glow discharge based on micro-structured-electrode (MSE) arrays was investigated by diode laser Atomic Absorption Spectroscopy. The microdischarge was studied at constant current in pure Ar for pressures ranging from 50 to 400 mbar. The measurements of the absolute population density of the excited 1s5 ,1 s 4 ,1 s 3, and 1s2 levels of Ar in the discharge revealed a population density of excited atoms in metastable and resonance states in the range 10 12 –10 15 cm −3 . The gas temperature and the electron number density were evaluated from the analysis of the Absorption line profiles, taking into account significant broadening mechanisms. The gas temperature, derived from the Doppler broadening, was found to increase with pressure from 380 K at 50 mbar to 1100 K at 400 mbar. The electron number density was calculated from the Stark broadening and shift, and it ranges from 9 × 10 14 to 5 × 10 15 cm −3 . The MSE-sustained discharges are combining the non-equilibrium character with the advantage of high-pressure, which recommends them for non-thermal plasma processing e.g. surface treatment, plasma chemistry and generation of UV and VUV radiation.
E J Teran - One of the best experts on this subject based on the ideXlab platform.
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assessment of sorption capability of montmorillonite clay for lead removal from water using laser induced breakdown Spectroscopy and Atomic Absorption Spectroscopy
Microchemical Journal, 2019Co-Authors: E J Teran, Maria Luciana Montes, Corina Iris Rodriguez, L Martino, Maria Angeles Quiroga, R Landa, R Torres M Sanchez, D Diaz M PaceAbstract:Abstract Laser–induced breakdown Spectroscopy (LIBS) and Atomic Absorption Spectroscopy (AAS) techniques were applied for quantitative analysis of the remaining Pb content in water samples after treatment with a raw montmorillonite (MMT) and an organic derivative (MMO) clays for heavy metal removal, an issue of crucial importance for decontamination of water bodies. The Pb sorption capabilities of MMT and MMO clays were assessed by using solutions with known Pb concentrations, in the range 100–500 ppm. To carry out the LIBS analysis, the samples were prepared in the form of solid pellets with powdered calcium hydroxide addition. The measurement conditions were optimized to achieve reliable analytical results and the plasma parameters, i.e., temperature and electron density, were obtained. For quantification purpose, a calibration curve was constructed with the Pb I emission line at 4057.8 A measured at the time window 30–45 μs by using reference samples with Pb concentrations in the range 56–715 ppm. The Pb residual content in the liquid samples determined with LIBS showed a good agreement with those measured with AAS. The sorption efficiency of Pb from contaminated water was calculated through a sorption percentage SPb%. The calculated SPb% was higher for MMT (56%–100%) than for MMO (27%–47%). The results also demonstrated the usefulness of LIBS method for the determination of Pb concentrations in liquid samples.