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Inorganic Sediment Chemistry and Elemental Speciation
Published in Renato Baudo, John P. Giesy, Herbert Muntau, Sediments:, 2020
Since adsorption of pollutants onto airborne and waterborne particles is a primary factor in determining the transport, deposition, reactivity, and potential toxicity of these materials, analytical methods should be related to the chemistry of the particle’s surface and/or to the metal species highly enriched on the surface. Basically there are three methodological concepts for determining the distribution of an element within or among small particles (Keyser et al. 1978, Förstner 1985): Analysis of single particles by X-ray fluorescence using either a scanning electron microscope (SEM) or an electron microprobe can identify differences in the matrix composition between individual particles. The total concentration of the element can be determined as a function of particle size. Other physical fractionation and preconcentration methods include density and magnetic separations.The surface of the particles can be studied directly by the use of electron microprobe X-ray emission spectrometry (EMP), electron spectroscopy for chemical analysis (ESCA), Auger electron spectroscopy (AES), and secondary ion-mass spectrometry. Depth-profile analysis determines the variation of chemical composition below the original surface.Solvent leaching—apart from the characterization of the reactivity of specific metals—can provide information on the behavior of pollutants under typical environmental conditions. Common single-reagent leachate tests, e.g., U.S. EPA, ASTM, IAEA, and ICES, use either distilled water or acetic acid (Theis & Padgett 1983). A large number of test procedures have been designed particularly for soil studies; these partly used organic chelators such as EDTA and DTPA (Sauerbeck & Styperek 1985).
Processing of metallurgical wastes with obtaining iron oxides nanopowders
Published in Cândida Vilarinho, Fernando Castro, Maria de Lurdes Lopes, WASTES – Solutions, Treatments and Opportunities II, 2017
I.Yu. Motovilov, V.A. Luganov, T.A. Chepushtanova, G.D. Guseynova, Sh.S. Itkulova
Electron microprobe analysis. The purpose of research—to determine the oxidized iron powder size; study the elemental composition of samples; study the morphological features of the powder: the geometric shape, the presence of pores and cracks.
Forensics of Environmental Dust
Published in Kathleen Hess-Kosa, Indoor Air Quality, 2018
The electron microprobe analyzer (EMA) is an ultra-micro analytical tool that can be used to enhance a light microscope, SEM, X-ray fluorescence, and cathode luminescence. It is also referred to as mass scanning.
Cloud condensation nuclei from the activation with ozone of soot particles sampled from a kerosene diffusion flame
Published in Aerosol Science and Technology, 2018
Symphorien Grimonprez, Alessandro Faccinetto, Sébastien Batut, Junteng Wu, Pascale Desgroux, Denis Petitprez
Soot particles are sampled with a diluting quartz microprobe, specifically developed for SMPS measurements. The microprobe is made of two co-annular quartz tubes, the outer one ending with a thin tip on which an aperture (100 µm) is obtained by abrasion. An automatic pressure regulation system is located downstream and enables a stable control of the pressure inside the probe, typically set to 5–20 mbar lower than the flame pressure. Nitrogen (5 L·min−1) flows between the quartz tubes up to the probe tip. Here, it mixes with the sample flow from the flame (1–10·mL min−1) that enters the probe tip orifice drawn in by the flame-probe pressure difference. The soot aerosol laden flow exiting the probe is then sampled before the automatic valve for further analysis and manipulations (online SMPS, injection into the reactor for aging experiments, soot deposition on TEM grids). The main advantage of this configuration consists the fast dilution of the sampled gas that quenches most chemical reactions and limits post-sampling particle coagulation phenomena. The low flame-probe pressure difference allows at the same time high-dilution ratio (around 1000) while minimizing flame perturbations. The particle concentration in the sampling line has to be higher than the counter’s detection limit but at the same time not as large as to trigger post-sampling aggregation.