Scientific interest in luminescent solar concentrators (LSCs) has reemerged mainly due to the application of semiconductor quantum dots (QDs) as highly efficient luminophores. Recently, LSCs have become attractive proposals for Building-Integrated photovoltaics (BIPV) since they could help conventional photovoltaics to improve sunlight harvesting and reduce production costs. However, most of the modern LSCs rely on heavy-metal QDs which are highly toxic and may cause environmental concerns.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
March 2023
Tb doped GeO-NaO glasses have been fabricated by conventional melt quenching technique using 0.3, 1, 3, and 5 %mol of terbium ions. The optical properties were studied by means of steady-state photoluminescence (excitation and emission spectra), and emission decay time.
View Article and Find Full Text PDFPlasmonic photothermal therapy (PPTT), as an increasingly studied treatment alternative, has been widely regarded mostly as a surface tissue treatment choice. Although some techniques have been implemented for interstitial tumors, these involve some grade of invasiveness, as the outer skin is usually broken to introduce light-delivering optical fibers or even catheters. In this work, we present a potential non-invasive strategy using the stereotactic approach, long employed in radiosurgery, by converging multiple near infrared laser beams for PPTT in tissue-equivalent optical phantoms that enclose small gel spheres and simulate interstitial tissue impregnated with plasmonic nanoparticles.
View Article and Find Full Text PDFIn this research, we conducted a systematic evaluation of the synthesis parameters of a multi-responsive core-shell nanocomposite (FeO nanoparticles coated by poly(N-isopropylacrylamide) (PNIPAM) in the presence of chitosan (CS) (FeO@PNIPAM-CS). Scanning electron microscopy (SEM) was used to follow the size and morphology of the nanocomposite. The functionalization and the coating of FeO nanoparticles (Nps) were evaluated by the ζ-potential evolution and Fourier Transform infrared spectroscopy (FTIR).
View Article and Find Full Text PDFWe present a new method to calculate the complex refractive index of spherical scatterers in a novel optical phantom developed by using homemade monodisperse silica nanospheres embedded into a polyester resin matrix and an ethanol-water mixture for applications in diffuse imaging. The spherical geometry of these nanoparticles makes them suitable for direct comparison between the values of the absorption and reduced scattering coefficients ( and , respectively) obtained by the diffusion approximation solution to the transport equation from scattering measurements and those obtained by the Mie solution to Maxwell's equations. The values of the optical properties can be obtained by measuring, using an ultrafast detector, the time-resolved intensity distribution profiles of diffuse light transmitted through a thick slab of the silica nanosphere phantom, and by fitting them to the time-dependent diffusion approximation solution to the transport equation.
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