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Vibrational Microspectroscopy for the Analysis of Surfaces and Particles on Surfaces
Published in Arthur T. Hubbard, The Handbook of Surface Imaging and Visualization, 2022
This application illustrates the ease with which the sample is selected and studied as well as the nondestructive nature of Raman microspectroscopy. It also shows the increased spatial resolution and increased immunity to spectral interferences as compared with microinfrared experiments. Typical problems with the Raman microprobe experiments, as with macro-Raman experiments, is the presence of fluorescence that often may make it difficult to detect the Raman signals. Best and other workers8 have had success in using microscope optics to spatially filter the fluorescence. Recent developments in FT-Raman microprobes, which use near infrared radiation as the excitation source, hold additional promise in reducing fluorescence and in increasing the usefulness of the technique.14 Occasionally, the high-power density radiation in Raman microspectroscopy can cause physical or chemical changes. Best detected that, using the green 514.5 nm line, enough localized heat was generated to result in red lead (Pb3 O4) being converted to massicot (PbO). He was able to avoid decomposition by using a different excitation wavelength.
Air Pollutants
Published in Ya. M. Grushko, A.P. Kotlobye, HANDBOOK OF Dangerous Properties of Inorganic and Organic Substances in Industrial Wastes, 2020
Massicot-yellow crystals, m.p. 600°C, ρ 8.70; insoluble in water. Present in wastes from the production of some plastics, pharmaceuticals, and reagents, lead compounds, lacquers and paints, glass, cement, articles made of rubber, sorage batteries, electrodes, enamels, polygraphic compositions, and matches; also in wastes of metallurgical plants.
Influence of drinking water quality on the formation of corrosion scales in lead-bearing drinking water distribution systems
Published in Journal of Environmental Science and Health, Part A, 2021
Lead corrosion scales were analyzed via UV/Vis spectroscopy, Fourier Transform Infrared (FTIR) spectroscopy, and XRD. UV/Vis spectra were obtained in the range of 200 to 800 nm in diffuse reflectance mode with 1 nm step size using a UV-3600 Shimadzu instrument equipped with a diffuse reflectance cell (Harrick, Praying Mantis). Infrared spectra were acquired in diffuse reflectance mode at a 4 cm−1 resolution and 64 scans per sample using a Harrick Praying Mantis. The UV/Vis and FTIR spectra were transformed to pseudo-absorption spectra using Kubelka-Munk function in the UVProbe® and OPUS® software, respectively. The XRD data were obtained on a Rigaku RPT 300 RC diffractometer using Co K-α (λ = 1.78890 Å) radiation over the range of 10-70° 2θ with a 0.02° step size. Selected pure lead compounds (Sigma-Aldrich, A.C.S reagent grade), plattnerite (β-PbO2), massicot (β-PbO), minium (Pb3O4), hydrocerussite (Pb3(CO3)2(OH)2), and cerussite (PbCO3), were used as references for solid phase characterization. For elemental analysis, 0.25-0.5 g solid samples were digested using U.S. EPA Method 3051 A. The acid digested samples were analyzed using an ICP-OES (Varian, Inc., Vista-Pro Axial). Inorganic carbon (IC) content was measured using a TOC-VCPN analyzer equipped with SSM-5000A (Shimadzu) for solid sample acidification.
Lead contamination in Chinese surface soils: Source identification, spatial-temporal distribution and associated health risks
Published in Critical Reviews in Environmental Science and Technology, 2019
Yunhui Zhang, Deyi Hou, David O’Connor, Zhengtao Shen, Peili Shi, Yong Sik Ok, Daniel C. W. Tsang, Yang Wen, Mina Luo
Pb is a natural constituent of the Earth's crust, and may occur naturally and heterogeneously in soils by the natural weathering and erosion of crustal materials or via deposition of Pb emitted into the Earth’s atmosphere by volcanic activities, totally accounting for 80% of natural sources (Callender, 2003; Hou, O’Connor, et al., 2017). Forest fires and biogenic sources also contribute to soil Pb, accounting for 10% each. Pb from natural sources can be separated as atmospheric soil dust (allochthonous) or detritic source (autochthonous) (Bao, Shen, Wang, & Tserenpil, 2016). Naturally derived lead in soil is commonly in the form of gelena (PbS, logKsp = −27.5) and in smaller quantities in cerussite (PbCO3), anglesite (PbSO4), pyromorphite (Pb5(PO4)3Cl), crocoite (PbCrO4), litharge (PbO) and Massicot (PbO) (Ruby, Davis, & Nicholson, 1994; Mulligan, Yong, & Gibbs, 2001; Laperche, Traina, Gaddam, & Logan,1996). Pb usually coexists with copper, zinc and silver, and the metallic form of Pb in nature is rare (Cheng & Hu, 2010).
A Comprehensive Approach to Speciation of Lead and Its Contamination of Firing Range Soils: A Review
Published in Soil and Sediment Contamination: An International Journal, 2019
Pogisego Dinake, Rosemary Kelebemang, Nicholas Sehube
Soil physical and chemical properties such as soil texture, soil pH, soil moisture, soil CEC and soil organic matter (OM) have significant impact on the distribution, mobility, solubility, bioavailability, bio-accessibility and fate of Pb in shooting range soils. Elevated soil moisture content, acidic soil pH and high soil OM provide favourable conditions for the weathering and transformation of metallic Pb shot to more reactive secondary Pb compounds (Hardison et al., 2004). The secondary Pb minerals that have been observed on the surfaces of weathered Pb shots and bullets include cerussite (PbCO3), hydrocerussite [Pb3(CO3)2(OH)2], massicot (PbO) and anglesite (PbSO4).