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This work explores the heterogeneous reaction between HUmic-LIke Substances (so-called HULIS) and ozone. Genuine atmospheric HULIS were extracted from aerosol samples collected in Chamonix (France) in winter and used in coated flow tube experiments to evaluate heterogeneous uptake of O₃ on such mixtures. The uptake coefficient (γ) was investigated as a function of pH (from 2.5 to 10), O₃ concentration (from 8 to 33 × 10¹¹ molecules cm⁻³), relative humidity (20 to 65%) and photon flux (from 0 to 1.66 × 10¹⁵ photons cm⁻² s⁻¹). Reactive uptake was found to increase in the irradiated experiment with pH, humidity and photon flux. The extract was characterized before and after exposure to O₃ and/or UV light in the attempt to elucidate the effect of the photochemical aging. Carbon content measurements, UV-vis spectroscopy and functional groups analysis revealed a decrease of the UV absorbance as well as of the carbon mass content, while the functionalization rate (COOH and C═O) and therefore the polarity increased during the simulated photochemical exposure.
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http://dx.doi.org/10.1021/es200587z | DOI Listing |
J Synchrotron Radiat
November 2025
State Key Laboratory of Chemical Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, People's Republic of China.
This study develops an integrated X-ray absorption spectroscopy (XAS) photoemission electron microscopy (PEEM) platform on beamline BL09U at the Shanghai Synchrotron Radiation Facility (SSRF), enabling nanoscale characterization of complex materials through energy-resolved imaging and local-area XAS. By using the wide range of energy tunability, full access to different polarizations and PEEM's surface sensitivity, we have established a gap-monochromator control system under the EPICS framework to synchronize the elliptically polarized undulator (EPU) gap and monochromator energy dynamically, optimizing photon flux stability for absorption fine structure analysis. Combining X-ray magnetic circular dichroism (XMCD) and X-ray magnetic linear dichroism (XMLD) with PEEM and local-area XAS, this platform achieves concurrent mapping of electronic structures and magnetic domains in ferromagnetic nano-patterns, as demonstrated through our studies of NiFe Permalloy using this system.
View Article and Find Full Text PDFJ Org Chem
September 2025
School of Chemistry, O'Brien Centre for Science, University College Dublin, Dublin 4, Belfield D04 N2E5, Ireland.
Ynones are attractive molecular building blocks owing to their electrophilic character, which can be exploited in a variety of functionalization strategies, giving rise to valuable reaction products. This work presents a photochemical strategy for the direct generation of ynones from aldehydes and substituted alkynes bearing radicofugal groups, such as sulfones. Using TBADT (tetrabutylammonium decatungstate) as a photocatalyst, the direct photochemical synthesis of a variety of ynones is achieved in high yields and short reaction times.
View Article and Find Full Text PDFAnal Chem
September 2025
Department of Analytical Chemistry, College of Chemistry, Jilin University, Changchun 130012, China.
Ginseng exosomes are a kind of promising extracellular vesicle containing unique bioactive components. However, the investigation on ginseng-derived exosomes is still in the initial stage. This study developed a photonic crystal-based Bragg scattering coupling electrochemiluminescence (BSC-ECL) biosensor for detection of miRNA396a-3p in exosome-like nanoparticles (GENs) and ginseng exosomes (Gexos).
View Article and Find Full Text PDFBiology (Basel)
August 2025
Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Viale Ferdinando Stagno d'Alcontres 31, 98166 Messina, Italy.
L. (MA) is a member of the Moraceae family, known as "white mulberry". Due to the high levels of bioactive compounds, mulberry plants can be considered a good source of nutrients and antioxidant compounds.
View Article and Find Full Text PDFJ Phys Chem B
September 2025
James Tarpo Jr. and Margaret Tarpo Department of Chemistry, Purdue University, 560 Oval Dr., West Lafayette, Indiana 47907, United States.
Raman spectroscopy is a powerful method for analyzing chemical compositions across diverse samples. Spontaneous Raman scattering (spRS) provides complete Raman spectra but typically yields low signal levels, requiring long signal integration times. In contrast, stimulated Raman scattering (SRS) produces much stronger signals, allowing for rapid spectral acquisition, and has been widely used to accelerate chemical imaging.
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