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We report on a temperature-, time-, and spectrally resolved study of the photoluminescence of type-I InP/ZnS colloidal nanocrystals with varying core size. By studying the exciton recombination dynamics we assess the exciton fine structure in these systems. In addition to the typical bright-dark doublet, the photoluminescence stems from an upper bright state in spite of its large energy splitting (∼100 meV). This striking observation results from dramatically lengthened thermalization processes among the fine structure levels and points to optical-phonon bottleneck effects in InP/ZnS nanocrystals. Furthermore, our data show that the radiative recombination of the dark exciton scales linearly with the bright-dark energy splitting for CdSe and InP nanocrystals. This finding strongly suggests a universal dangling bonds-assisted recombination of the dark exciton in colloidal nanostructures.
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http://dx.doi.org/10.1021/acsnano.5b07065 | 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 Fluoresc
September 2025
Chemical Engineering Department, College of Engineering, University of Ha'il, P.O. Box 2440, 81441, Ha'il, Saudi Arabia.
This review delivers a focused and critical evaluation of recent progress in the green synthesis of carbon quantum dots (CQDs), with particular attention to state-of-the-art approaches utilizing renewable biomass as precursors. The main objective is to systematically examine innovative, environmentally friendly methods and clarify their direct influence on the core properties and photocatalytic performance of CQDs. The novelty of this review stems from its comprehensive comparison of green synthetic pathways, revealing how specific processes determine key structural, optical, and electronic attributes of the resulting CQDs.
View Article and Find Full Text PDFJ Virol
September 2025
Université catholique de Louvain, de Duve Institute, Brussels, Belgium.
Unrelated pathogens, including viruses and bacteria, use a common short linear motif (SLiM) to interact with cellular kinases of the RSK (p90 S6 ribosomal kinase) family. Such a "DDVF" (D/E-D/E-V-F) SLiM occurs in the leader (L) protein encoded by picornaviruses of the genus , including Theiler's murine encephalomyelitis virus (TMEV), Boone cardiovirus (BCV), and Encephalomyocarditis virus (EMCV). The L-RSK complex is targeted to the nuclear pore, where RSK triggers FG-nucleoporins hyperphosphorylation, thereby causing nucleocytoplasmic trafficking disruption.
View Article and Find Full Text PDFSmall
September 2025
State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China.
Polyethylene terephthalate (PET) glycolysis presents an effective solution to address plastic pollution while promoting the utilization of renewable resources. It is highly important to gain in-depth insights into the identification of the well-defined active sites and the structure-activity relationships in PET glycolysis. Herein, PW@UiO-67 with different exposed crystal facets, i.
View Article and Find Full Text PDFRSC Adv
September 2025
Departament de Química, Universitat Autònoma de Barcelona Bellaterra 08193 Barcelona Spain
Mammalian ALOX15 are allosteric enzymes but the mechanism of allosteric regulation remains a matter of discussion. Octyl (-(5-(1-indol-2-yl)-2-methoxyphenyl)sulfamoyl)carbamate inhibits the linoleate oxygenase activity of ALOX15 at nanomolar concentrations, but oxygenation of arachidonic acid is hardly affected. The mechanism of substrate selective inhibition suggests inter-monomer communication within the allosteric ALOX15 dimer complex, in which the inhibitor binding to monomer A induces conformational alterations in the structure of the active site of monomer B.
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