Search results for "nanoparticle"

Physical properties of aerosol particles measured from a bubbling fluidized bed boiler

2015

Abstract Increased use of biomass and waste fuels, and the consequent corrosion problem have led to an increased need to study and monitor the combustion processes. This study presents an extensive physical characterization of aerosol particles measured from a bubbling fluidized bed boiler with different fuel mixtures and optional ferric sulfate feeding. The fuel mixtures included bark, sludge, peat and solid recovered fuel. Previously, the characterization of the particles analyzed from a fluidized bed reactor has mainly focused on chemical off-line analysis of collected impactor samples, large coarse mode particles or laboratory-scale reactors. In this study, the focus is in the particle …

Physicochemical investigation of acrylamide solubilization in sodium bis(2-ethylhexyl)sulfosuccinate and lecithin reversed micelles.

2003

The state of acrylamide confined within dry sodium bis(2-ethylhexyl)sulfosuccinate (AOT) and lecithin reversed micelles dispersed in CCl4 has been investigated by FTIR and H-1 NMR spectroscopy. Measurements have been performed at 25 degreesC as a function of the acrylamide-to-surfactant molar ratio (R) at a fixed surfactant concentration (0.1 mol kg(-1)). The analysis of experimental data, corroborated by the results of SAXS measurements, is consistent with the hypothesis that acrylamide is quite uniformly distributed among reversed micelles mainly located in proximity to the surfactant head-group region and that its presence induces significant unidimensional growth of micellar aggregates.…

The effect of heat treatment on the morphology and mobility of Au nanoparticles

2020

This work was supported by The Centre National de la Recherche Scientifique (CNRS) of France and the French Embassy Program. The authors are also grateful for partial support by COST Action CA15216, the Estonian Science Foundation (grants PUT1689 and PUT1372), the Estonian Centre of Excellence in Zero Energy and Resource Efficient Smart Buildings and Districts, ZEBE, grant 2014-2020.4.01.15.0016 and Latvian Science Council grant lzp-2018/2-0083.

Humidity-enhanced sub-ppm sensitivity to ammonia of covalently functionalized single-wall carbon nanotube bundle layers

2017

International audience; A low-cost method for carbon nanotubes (CNTs) network production from solutions on flexible polyethylene naphthalate substrates has been adopted to prepare high quality and well characterized SWCNT bundle layers to be used as the active layer in chemiresistor gas sensors. Two types of SWCNTs have been tested: pristine SWCNTs, deposited from a surfactant solution, and covalently functionalized SWCNTs, deposited from a dimethyl-acetamide solution. The humidity effects on the sensitivity of the SWCNTs network to NH3 have been investigated. The results show that relative humidity favors the response to NH3, confirming recent theoretical predictions. The COOH-functionaliz…

Oligonucleotides-decorated-poly(N-vinyl pyrrolidone) nanogels for gene delivery

2013

Pulsed electron-beam irradiation of a semi-dilute poly(N-vinyl pyrrolidone) (PVP) aqueous solution in the presence of acrylic acid has led to a carboxyl functionalized nanogel system. Nanoparticles hydrodynamic size and surface charge density, in water and as a function of pH, were investigated by dynamic light scattering and laser doppler velocimetry, respectively. Nanogels (NGs) were proved not to be cytotoxic at the cellular level. Indeed, they rapidly bypass the cellular membrane to accumulate in specific cell portions of the cytoplasm, in the perinuclear area. The availability of pendant carboxyl groups on the crosslinked PVP NGs core prompted us to attempt their decoration with a sing…

Selective Recognition and Sensing of Succinate vs. Other Aliphatic Dicarboxylates by Thiourea-Functionalized Gold Nanoparticles

2016

Gold nanoparticles functionalized with thiourea moieties have been used as selective colorimetric sensors for the naked-eye detection of succinate versus other aliphatic dicarboxylates, all of them as their TBA salts. The detection process is based on the interparticle aggregation triggered by coordination of the end-carboxylates to the thiourea moieties of two different nanoparticles. This nanoparticle aggregation results in a batochromic shift of the plasmon resonance band and a visual color change from red to blue.

Visual Health Nanocomposites: Present and Future

2021

Background: In recent years, the therapeutics for eye diseases as retinopathy diabetic, dry eye, glaucoma and contact lenses fabrication are including nanocompounds as ocular drug delivery systems, biomarkers for detection of eye diseases, copper and silver ions that has been incorporated by means of the nanotechnology for the production of less toxic and more effective alternatives. Several compounds such as silver nanoparticles, turmeric-based nanocomposites, neovascularization blockers and nanoparticles extracted from the plant Costus pictus among others have been researched for this purpose. Those compounds are some of the promising research efforts that are studying and will contribute…

Silver nanoparticles in resin luting cements: antibacterial and physiochemical properties

2016

Background Silver has a long history of use in medicine as an antimicrobial and anti-inflammatory agent. Silver nanoparticles (NAg) offer the possibility to control the formation oral biofilms through the use of nanoparticles with biocidal, anti-adhesive, and delivery abilities. This study aims to evaluate the antibacterial effect of resin luting cements with and without NAg, and their influence on color, sorption and solubility. Material and methods NAg were incorporated to two dual-cured resin cements (RelyX ARC (RA) color A1 and RelyX U200 (RU) color A2) in two concentrations (0.05% and 0.07%, in weight), obtaining six experimental groups. Disc specimens (1x6mm) were obtained to verify t…

Inulin Coated Gold Nanoparticles As a Potential Tool For Cancer Therapy

2014

COUPLING ELECTROCHEMISTRY TO ELECTROSPRAY: A NOVEL PREPARATION OF GOLD NANOSTRUCTURES

2013

nanoparticles on ITO (Indium tin oxide) coated glass using the electrospray (ESI) method Method:The starting point of this study is that the ESI/MS spectrum (Figure 1) of an ethanolic solution of HAuCl 4 shows a reduction process of Au (III) strongly dependent on the Cone Voltage (CV) values (20, 80, 150 V), affording to the ion at m/z 197 (Au+). Further, the decrease of the abundance of this ion at the highest cone voltage suggests the subsequent its reduction with the formation of Au 0 . Figure 1: ESI/MS spectra of an ethanolic solution of HAuCl4 at various cone voltages: Conclusion: Such experimental evidence leads us to use electrospray technique as a preparative tool to obtain the form…