The Raman spectra of the minerals cerrusite (PbCO(3)), hydrocerrusite (Pb(2)(OH)(2)CO(3)), phosgenite (Pb(2)CO(3)Cl(2)) and laurionite (Pb(OH)Cl) have been used to qualitatively determine their presence. Laurionite and hydrocerrusite have characteristic hydroxyl stretching bands at 3506 and 3576 cm(-1). Laurionite is also characterised by broad low intensity bands centred at 730 and 595 cm(-1) attributed to hydroxyl deformation vibrations. The minerals cerrusite, hydrocerrusite and phosgenite have characteristic CO (nu(1)) symmetric stretching bands observed at 1061, 1054 and 1053 cm(-1). Phosgenite displays complexity in the CO (nu(3)) antisymmetric stretching region with bands observed at 1384, 1327 and 1304 cm(-1). Cerrusite shows bands at 1477, 1424, 1376 and 1360 cm(-1). The hydrocerrusite Raman spectrum has bands at slightly different positions from cerrusite, with bands at 1479, 1420, 1378 and 1365 cm(-1). The complexity of the nu(3) region is also reflected in the nu(2) and nu(4) regions with the observation of multiple bands. Laurionite is characterised by two intense bands at 328 and 272 cm(-1) attributed to PbO and PbCl stretching bands. Importantly, all four minerals are characterized by their Raman spectra, enabling the mineral identification in leachates and contaminants of environmental significance.
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http://dx.doi.org/10.1016/s1386-1425(03)00054-4 | DOI Listing |
Spectrochim Acta A Mol Biomol Spectrosc
January 2025
Institute of Chemistry, Military University of Technology, Kaliskiego 2, PL-00908 Warsaw, Poland.
Molecular arrangement in the chiral smectic phases of the glassforming (S)-4'-(1-methylheptylcarbonyl)biphenyl-4-yl 4-[7-(2,2,3,3,4,4,4-heptafluorobutoxy) heptyl-1-oxy]benzoate is investigated by X-ray diffraction. An increased correlation length of the positional short-range order in the supercooled state agrees with the previous assumption of the hexatic smectic phase. However, the registered X-ray diffraction patterns are not typical for the hexatic phases.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
January 2025
Department of Chemistry, University of Copenhagen, Universitetsparken 5, Copenhagen Ø, DK-2100, Denmark. Electronic address:
We have recorded the gas phase spectrum of isoprene at room temperature from the mid-infrared range and into the visible range (600 cm to 17050 cm). Absorption spectra were obtained by Fourier transform infrared, conventional dispersion ultraviolet-visible-near-infrared and cavity ring-down spectroscopy to cover the entire range with a resolution comparable to that of the instruments on the James Webb Space Telescope. We have assigned the CH-stretching fundamental and overtone bands corresponding to the Δv=1-6 transitions based on anharmonic vibrational calculations using normal mode and local mode models, for the lower- and higher-energy regions, respectively.
View Article and Find Full Text PDFLangmuir
January 2025
Institute for Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8503, Japan.
The amount of incorporation of linear alcohols and ethers in HSiWO·6HO (HSiW·6HO, 50 wt %) supported on silica (SiO) was estimated by a conventional volumetric method and infrared (IR) spectroscopy, and the state of involved molecules was elucidated. First, the attribution of the key IR band at 2200 cm, which was observed for the water of crystallization of HSiW·6HO, to HO species (protons) was verified by coincident observation of thermogravimetric-differential thermal analysis, X-ray diffraction (XRD), and IR spectroscopy during thermal treatment in addition to the isotope exchange with DO. The 2200 cm band was gradually decreased in intensity by increasing the amount of adsorption of pyridine and was totally consumed at saturation, while the volumetric method provided the accurate number of included pyridine molecules.
View Article and Find Full Text PDFCirc Res
January 2025
Department of Integrative Pathophysiology, Medical Faculty Mannheim, DZHK Partnersite Mannheim-Heidelberg, University of Heidelberg, Germany (S.L.).
This review examines the giant elastic protein titin and its critical roles in heart function, both in health and disease, as discovered since its identification nearly 50 years ago. Encoded by the TTN (titin gene), titin has emerged as a major disease locus for cardiac disorders. Functionally, titin acts as a third myofilament type, connecting sarcomeric Z-disks and M-bands, and regulating myocardial passive stiffness and stretch sensing.
View Article and Find Full Text PDFJ Xenobiot
December 2024
Department of Chemical Engineering, University of Pretoria, Pretoria 0028, South Africa.
The direct discharge of cationic surfactants into environmental matrices has exponentially increased due to their wide application in many products. These compounds and their degraded products disrupt microbial dynamics, hinder plant survival, and affect human health. Therefore, there is an urgent need to develop electroanalytical assessment techniques for their identification, determination, and monitoring.
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