Search results for "Light excitation"
showing 3 items of 3 documents
Alkoxy-styryl DCDHF fluorophores
2010
A photostable dicyanomethylenedihydrofuran fluorophore which contains electron-donating alkoxy groups is described. This chromophore is highly environmentally-sensitive, which is a remarkable property for a fluorescent reporter. Its light excitation also enables, in low viscous solvents, the formation of dark states whose radical or triplet nature is ruled out.
Hexagonal boron nitride luminescence dependent on vacuum level and surrounding gases
2015
Abstract Gas sensing properties of hBN powder bulk and nanosize were studied. It was demonstrated that for hBN powders with grain sizes of 70 nm, 1 μm and 5 μm the native defect-induced luminescence observed at 400 nm under 265 nm light excitation and room temperature is sensitive to oxygen gas reducing luminescence intensity. The highest value of luminescence intensity is reached when sample is in vacuum. Results obtained allow conclusion that the hBN powder is prospective for sensing of oxygen gas. Some material properties such as dependence of luminescence intensity on vacuum level and pumping time, ratio of luminescence intensity when sample is in vacuum and gas, its dependence on mater…
Near-infrared photochemistry assisted by upconverting nanoparticles
2019
Abstract Upconverting nanoparticles (UCNPs) combine unique optical and imaging properties with high chemical and biological stability. The capability of UCNPs to emit visible light upon near-infrared light excitation, in an anti-Stokes fashion, is extremely attractive for the design of light-responsive nanomaterials whose action can be controlled spatially and temporally. In this chapter, we analyze the most promising approaches developed so far to functionalize the surface of UCNPs with photoactivatable organic and inorganic molecular systems. In particular, we emphasize the key advances in the design of upconverting nanosystems that exploit bioactive transition metal complexes.