Silicon nanocrystals embedded in a silicon-rich silicon oxide matrix doped with Er3+ ions have been fabricated by electron cyclotron resonance plasma-enhanced chemical vapor deposition. Indirect excitation of erbium photoluminescence via silicon nanocrystals has been investigated. Temperature quenching of the photoluminescence originating from the silicon nanocrystals and the erbium ions has be...

Europium tris-b-diketonates (Eu(L)3 nH2O) show concentration quenching of luminescence in toluene solutions due to the formation of weakly luminescent dimers. Addition of water to the concentrated toluene solutions of Eu(L)3 nH2O unexpectedly enhances quantum yield ðfÞ and lifetime of Eu 3+ luminescence by causing dissociation of dimers and by reducing quenching of excited Eu through the ligand...

Fluorescence quenching spectrometry was applied to study the interactions between gold colloidal nanoparticles and alpha-fetoprotein (AFP). Experimental results show that the gold nanoparticles can quench the fluorescence emission of adsorbed AFP effectively. Furthermore, the intensity of fluorescence emission peak decreases monotonously with the increasing gold nanoparticles content. A mechani...

We simulate the Ising model on a set of fixed random φ graphs, which corresponds to a quenched coupling to 2D gravity rather than the annealed coupling that is usually considered. We investigate the critical exponents in such a quenched ensemble and compare them with measurements on dynamical φ graphs, flat lattices and a single fixed φ graph. Submitted to Phys Lett B. 1 Address: Sept. 1993 199...

In the last decade we have seen an enormous increase in the size and quality of spectroscopic galaxy surveys, both at low and high redshift. New statistical techniques to analyse large portions of galaxy spectra are now finding favour over traditional index based methods. Here we will review a new robust and iterative Principal Component Analysis (PCA) algorithm, which solves several common iss...

We prove that stimulated emission is by far the dominant quenching mechanism for providing super-resolution in fluorescence microscopy with a red-shifted depletion beam. Our evidences are based on simultaneously measuring fluorescence quenching and photon gain in the quenching beam. Measurements were performed for several fluorescent dyes including fluorescent proteins over a wide spectral rang...

The linear peptide gramicidin forms prototypical ion channels specific for monovalent cations and has been extensively used to study the organization, dynamics, and function of membrane-spanning channels. We have analyzed the localization of the functionally important tryptophan residues of the membrane-bound channel and non-channel conformations of gramicidin utilizing a novel dual fluorescenc...

Single-bubble sonoluminescence (SBSL) in water has been studied in the presence of low concentrations of simple organic compounds. For a given concentration of aliphatic alcohol, the degree of quenching follows the order, ethanol< I -propanol< 1-butanol, Preliminary experiments with simple we& acids and bases indicate that SBSL quenching only occurs when the pH is adjusted such that the solutes...

In this paper, highly (up to 5.25 mol% Er2O3) Er-doped phosphate bulk glasses were synthesized by conventional melt-quenching method and their physical, thermal and spectroscopic properties are reported. The influence of Er doping concentration on emission spectra and lifetimes was investigated in order to study the concentration quenching effect on luminescence performance and therefore to eva...