We report strong isotope effects for the protic ionic liquid triethylammonium methanesulfonate [TEA][OMs] by means of deuterium solid-state NMR spectroscopy covering broad temperature ranges from 65 K to 313 K. Both isotopically labelled PILs differ in non-deuterated and fully deuterated ethyl groups of the triethyl ammonium cations. The N-D bond of both cations is used as sensitive probe for hydrogen bonding and structural ordering. The H NMR line shape analysis provides the deuteron quadrupole coupling constants and the characteristics of a broad heterogeneous phase with simultaneously present static and mobile states indicating plastic crystal behavior. The temperatures where both states are equally populated differ by about 80 K for the two PILs, showing that deuteration of the ethyl groups in the trialkylammonium cations tremendously shifts the equilibrium towards the static state. In addition, it leads to a significant less cooperative transition, associated with a significantly reduced standard molar transition entropy.
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http://dx.doi.org/10.1002/cphc.202200557 | DOI Listing |
Environ Sci Pollut Res Int
January 2025
V.S. Sobolev Institute of Geology and Mineralogy Siberian Branch of Russian Academy of Sciences, 3 Koptuga Av, Novosibirsk, Russia, 630090.
Mosses and lichens are often used to assess atmospheric deposition of Pb. The most widely used method for determining this isotope is gamma spectrometric analysis. There is often a need to enhance the sensitivity of the method, which can be achieved by pre-concentrating Pb.
View Article and Find Full Text PDFInt Ophthalmol
January 2025
Department of Ophthalmology, Staedtisches Klinikum Dessau, Brandenburg Medical School Theodor Fontane, Dessau, Germany.
Purpose: Uveal melanoma (UM) is the most common primary ocular malignancy. The size and location of the tumor are decisive for brachytherapy with the β-emitting ruthenium-106 (Ru-106) plaque. The treatment of juxtapapillary and juxtafoveolar UM may be challenging because of the proximity or involvement of the macula and optic nerve and high recurrence rates.
View Article and Find Full Text PDFAm J Biol Anthropol
January 2025
Department of Anthropology, National Museum of Natural History, Smithsonian Institution, Washington, District of Columbia, USA.
Introduction: Contemporary dietary and nutritional transitions are commonplace, but difficult to study directly. In Brazil, and Latin America, this generalized process, leading to current obesity and malnutrition problems, started more than four decades ago. Although body weight and food availability are used to measure changes, not much information on food consumption and nutrition exist.
View Article and Find Full Text PDFInt J Mol Sci
December 2024
Nuclear Medicine Department, University of Medicine and Pharmacy "Carol Davila" Bucharest, 050474 Bucharest, Romania.
Starting from the metabolic profile of type 2 diabetes mellitus (T2DM), we hypothesized that the mechanisms of ¹³¹I-induced cardiotoxicity differ between patients diagnosed with differentiated thyroid cancer (DTC) with/without T2DM, with metformin potentially acting as a cardioprotective agent by mitigating inflammation in patients with T2DM. To address this hypothesis, we quantified, using ELISA, the serum concentration of several key biomarkers that reflect cardiac injury (NT-proBNP, NT-proANP, ST2/IL-33R, and cTn I) in 74 female patients with DTC/-T2DM and 25 with DTC/+T2DM treated with metformin. All patients received a cumulative oral dose of I exceeding 150 mCi (5.
View Article and Find Full Text PDFMaterials (Basel)
December 2024
Institute of Safety Engineering, Fire University, 52/54 Słowackiego St., 01-629 Warsaw, Poland.
The concentration of natural radionuclides Ra, Th and K in ceramic tiles manufactured in Poland is presented in this paper. The concentration of natural radioactive isotopes in the tested samples was determined using a low-level digital gamma ray spectrometer equipped with an HPGe semiconductor detector. The mean concentrations of Ra, Th and K in the analyzed samples were found to be 48 ± 3 Bq∙kg, 49 ± 3 Bq∙kg and 476 ± 23 Bq∙kg, respectively.
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