New hybrid organic-inorganic dyes based on an azide-functionalized cubic octasilsesquioxane (POSS) as the inorganic part and a 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BDP) chromophore as the organic component have been synthesized by copper(I)-catalyzed 1,3-dipolar cycloaddition of azides to alkynes. We have studied the effects of the linkage group of BDP to the POSS unit and the degree of functionalization of this inorganic core on the ensuing optical properties by comparison with model dyes. The high fluorescence of the BDP dye is preserved in spite of the linked chain at its meso position, even after attaching one BDP moiety to the POSS core. The laser action of the new dyes has been analyzed under transversal pumping at 532 nm in both the liquid phase and when incorporated into solid polymeric matrices. The monosubstituted new hybrid dye exhibits high lasing efficiency of up to 56 % with high photostability, with its laser output remaining at the initial value after 4×10(5) pump pulses in the same position of the sample at a repetition rate of 30 Hz. However, functionalization of the POSS core with eight fluorophores leads to dye aggregation, as quantum mechanical simulation has revealed, worsening the optical properties and extinguishing the laser action. The new hybrid systems based on dye-linked POSS nanoparticles open up the possibility of using these new photonic materials as alternative sources for optoelectronic devices, competing with dendronized or grafted polymers.
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Talanta
December 2024
The First Dongguan Affiliated Hospital, Guangdong Medical University, Dongguan, 523700, China. Electronic address:
This research presents a systematic review of the application of metal-organic frameworks (MOFs) to detect volatile organic compounds (VOCs). VOCs, compounds with high vapor pressure at ambient temperature and normal pressure, are widely present in a variety of industrial and living environments. VOCs are not only hazardous to the environment but also have a severe impact on human health.
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January 2025
Department of Graphic Arts and Photophysics, Faculty of Chemical Technology, University of Pardubice, Studentská 573, Pardubice, 532 10, Czech Republic.
Radio frequency magnetron co-sputtering method employing GeTe and Sc targets was exploited for the deposition of Sc doped GeTe thin films. Different characterization techniques (scanning electron microscopy with energy-dispersive X-ray analysis, X-ray diffraction, atomic force microscopy, sheet resistance temperature-dependent measurements, variable angle spectroscopic ellipsometry, and laser ablation time-of-flight mass spectrometry) were used to evaluate the properties of as-deposited (amorphous) and annealed (crystalline) Ge-Te-Sc thin films. Prepared amorphous thin films have GeTe, GeTeSc, GeTeSc, GeTeSc and GeTeSc chemical composition.
View Article and Find Full Text PDFDent Mater
January 2025
Department of Engineering Mechanics, School of Civil Engineering, Wuhan University, Wuhan, Hubei 430072, China; Wuhan University Shenzhen Research Institute, Shenzhen 518108, China. Electronic address:
Objective: Photopolymerized resin composites are widely used as dental filling materials. However, the shrinkage stress generated during photopolymerization can lead to marginal microcracks and eventual restoration failure. Accurate assessment of the stress evolution in dental restorations, particularly in complex cavity geometries, is critical for improving the performance and longevity of the dental filling materials.
View Article and Find Full Text PDFPhys Rev Lett
December 2024
CERN, Geneva, Switzerland.
High-energy nuclear collisions create a quark-gluon plasma, whose initial condition and subsequent expansion vary from event to event, impacting the distribution of the eventwise average transverse momentum [P([p_{T}])]. Disentangling the contributions from fluctuations in the nuclear overlap size (geometrical component) and other sources at a fixed size (intrinsic component) remains a challenge. This problem is addressed by measuring the mean, variance, and skewness of P([p_{T}]) in ^{208}Pb+^{208}Pb and ^{129}Xe+^{129}Xe collisions at sqrt[s_{NN}]=5.
View Article and Find Full Text PDFPhys Rev Lett
December 2024
Vienna Center for Quantum Science and Technology, Atominstitut, TU Wien, 1020 Vienna, Austria.
The efficient readout of the relevant information is pivotal for quantum simulation experiments. Often only single observables are accessed by performing standard projective measurements. In this work, we implement an atomic beam splitter by controlled outcoupling that enables a generalized measurement scheme.
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