FTIR-ATR measurements permit detailed structural analysis and in situ titration of carboxylate-terminated self-assembled monolayers. Both monomeric and dimeric/oligomeric acid groups are seen, and their acid-base behavior is directly monitored. Monomers that are hydrogen bonded only to surrounding water molecules have a pKa = 4.9, while the pKa for the aggregated molecules is 9.3.
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http://dx.doi.org/10.1021/ja037610u | DOI Listing |
Chem Sci
September 2024
School of Chemistry and Chemical Engineering, Chongqing Key Laboratory of Chemical Theory and Mechanism, Chongqing University Chongqing 401331 China
Sci Total Environ
September 2024
Institute of Polar Sciences, National Research Council (CNR-ISP), Spianata S. Raineri 86, 98122 Messina, Italy. Electronic address:
Microbial colonization on plastic polymers has been extensively explored, however the temporal dynamics of biofilm community in Antarctic environments are almost unknown. As a contribute to fill this knowledge gap, the structural characteristics and microbial diversity of the biofilm associated with polyvinyl chloride (PVC) and polyethylene (PE) panels submerged at 5 m of depth and collected after 3, 9 and 12 months were investigated in four coastal sites of the Ross Sea. Additional panels placed at 5 and 20 m were retrieved after 12 months.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
May 2024
Faculty of Chemistry, Jagiellonian University in Krakow, Gronostajowa 2, 30-387 Krakow, Poland. Electronic address:
In this work, we investigated the oxidative stress-related biochemical alterations in red blood cells (RBCs) and their membranes with the use of spectroscopic techniques. We aimed to show their great advantage for the in situ detection of lipid classes and secondary structures of proteins without the need for their extraction in the cellular environment. The exposition of the cells to peroxides, t-butyl hydroperoxide (tBOOH) or hydrogen peroxide (HO) led to different degradation processes encompassing the changes in the composition of membranes and structural modifications of hemoglobin (Hb).
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
November 2023
Institute of Environmental Sciences, Bogazici University, Bebek, Istanbul, 34342, Türkiye.
Polyaniline (PANI) is a promising conducting polymer for surface modification of TiO to overcome limitations of the use of visible light and attain increased photocatalytic efficiency for the removal of organic contaminants. In this study, a series of polyaniline modified TiO (PANI-TiO) composites were prepared by using "in-situ" chemical oxidation polymerization method. The composites were systematically characterized by Fourier transform infrared spectroscopy (equipped with an attenuated total reflection accessory, FTIR-ATR), Raman spectroscopy, X-ray diffractometry (XRD), scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDAX), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible diffuse reflectance spectroscopy (UV-DRS), photoluminescence spectroscopy (PL), nitrogen (N) physisorption (Brunauer - Emmett - Teller surface area (S) and Barrett-Joyner-Halenda (BJH) pore size analysis), thermogravimetry-derivative thermogravimetry (TG-DTG) techniques.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
November 2023
SMAArt, c/o Dipartimento di Chimica, Università degli Studi di Perugia, via Elce di Sotto 8, I-06123 Perugia, Italy; Istituto CNR di Scienze e Tecnologie Chimiche (CNR-SCITEC), c/o Dipartimento di Chimica, Università degli Studi di Perugia, via Elce di Sotto 8, I-06123 Perugia, Italy; Accademia Nazionale dei Lincei, via della Lungara 10, 00165 Rome, Italy.
This paper demonstrates the efficacy of portable mid-infrared spectroscopy as a diagnostic tool for revealing the presence of lead carboxylates on artworks, in situ, without sampling. Samples of cerussite and hydrocerussite - the main components of lead white - were separately mixed with linseed oil, and artificially aged in two steps. Their compositional changes have been monitored over time by infrared spectroscopy in two investigation modes: absorption (benchtop instrument) and reflection (portable instrument), and by XRD spectroscopy.
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