Search results for "silica."

Inhomogeneous properties of defects in amorphous silica probed by time-resolved luminescence

2008

Inhomogeinity of Oxygen deficient centers in silica probed by nanosecond time-resolved luminescence measurements

2008

UPTAKE OF SILICA COVERED QUANTUM DOTS ON LIVING CELLS: LONG TERM VITALITY AND MORPHOLOGY STUDY ON HYALURONIC ACID BIOMATERIALS

2015

In this work we prepared colloidal CdSe-CdS core-shell nanocrystal emitting @625 nm and, by a micro-emulsion procedure of water in oil inverse micelle, we encapsulated a single dot inside each silica sphere. In this way the nanoparticles became biocompatible, are simply to prepare and could be used also in a water based environment. Moreover, the silica shield is transparent to the wavelengths of interest.

Radiation-induced effects in silica based glasses: experimental and theoretical results

2008

Silica as a green exfoliant agent for graphene oxidepolymer nanocomposites prepared in the melt

2017

For the first time, solid-state exfoliant agents were used to hinder the re-aggregation of graphene oxide (GO) during melt processing with polyamide 6 (PA6). This technique drastically reduces the time and difficulty related to solvent (removal, disposal, etc.), and avoids water consumption, since in this case 150 mL of water under mild operative conditions are enough to prepare the amount of GOS necessary for the realization of almost 100 grams of PA6- GOS nanocomposites with outstanding ultimate properties.

Zero phonon line associated with Non Bridging Oxygen Hole Center in silica: comparison between bulk and surface properties

2008

Resonance Raman of oxygen dangling bonds in amorphous silicon dioxide

2017

We investigate the origin of a resonance Raman band induced by ionizing radiation in amorphous silicon dioxide (silica glass), which can be detected under ultraviolet laser excitation. A silica sample, rich of oxygen-excess related defects, was prepared by treating some length of a pure-silica-core multimode fiber in an O2 atmosphere (at high temperature and pressure) and by irradiating it with X-rays at 10 MGy(SiO2) dose. A micro-Raman study revealed a gaussian band peaking at 896 cm−1 with a full width at half maximum of 32 cm−1, which could be detected by exciting the sample with the 325-nm line of a HeCd laser. This spectral feature is absent in the Raman spectra performed with the 442-…

Impact of silicates and detergents on primary production and total biomass of algae in a short-term laboratory experiment

2006

UV-Visible down conversion based on nanosized silica promising for CPV applications

2014

Inconsistencies in the pozzolanic strength activity index (SAI) for silica fume according to EN and ASTM

2014

Published version of an article in the journal: Materials and Structures. Also available from the publisher at: http://dx.doi.org/10.1617/s11527-014-0457-6 Open Access New supplementary cementitious materials claimed to possess pozzolan properties emerge frequently. This development is driven both by economic and environmental pressures. Properties of new materials are compared with those of materials already well known, such as silica fume. Several test methods are standardized for making such comparisons, regulated by both European (EN) and American (ASTM) standards. Standardization indicates that procedures are secured to make comparisons valid and informative. In this article the sensit…