We have investigated the degree of dispersion of single-walled carbon nanotubes (SWNTs) in solution using laser spectroscopic techniques. SWNTs were suspended in aqueous media using a sodium dodecyl sulfate (SDS) surfactant. SWNTs with different dispersion states were prepared by controlling the intensity and duration of sonication and centrifugation. The absorption and fluorescence spectroscopic techniques were employed to characterize the different dispersion state of the prepared samples. Nanotube suspensions with better dispersion showed higher fluorescence and sharper absorption peaks. The fluorescence data were characterized as a function of the nanotube chirality, and absorption peak shifts were analyzed depending on the first and second van Hove singularities (vHs) of semiconducting nanotubes.
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Food Addit Contam Part A Chem Anal Control Expo Risk Assess
January 2025
UMR SayFood 0782, Université Paris-Saclay, INRAE, Palaiseau, AgroParisTech, France.
Assessing the contamination of paper and board (P&B) food packaging materials poses significant challenges due to the sensitivity limits of analytical methods and the low precision of sampling processes. This study aims to enhance the understanding of P&B food packaging contamination by investigating the distribution of contaminants at different scales using a combination of chromatographic and spectroscopic techniques. A total of 36 substances were targeted, including phthalates, photoinitiators, and bisphenol A.
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VIT University, Materials Chemistry Division, School of Advanced Sciences, VIT University, 632014, Vellore, INDIA.
Amidines are a vital class of bioactive compounds and often necessitate multiple components for their synthesis. Therefore, exploring efficient and sustainable methodologies for their synthesis is indispensable. Herein, we disclose an alternative and greener method for synthesizing an unexplored new class of amidines through the photochemical synergistic effect of copper/nitroxyl radical catalysis.
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Universidad Nacional de Tucuman Facultad de Bioquimica Quimica y Farmacia, Chemistry, Av. Kirchner 1900, 4000, San Miguel de Tucumán, ARGENTINA.
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January 2025
Max Planck-EPFL Laboratory for Molecular Nanoscience, Institut de Physique de la Matière Condensée, École Polytechnique Fédérale de Lausanne, CH 1015 Lausanne, Switzerland, 1005, Lausanne, SWITZERLAND.
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January 2025
College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China.
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