Search results for "METALS"
showing 10 items of 2013 documents
Polyamide/carbonaceous particles nanocomposites fibers: Morphology and performances
2015
In this work, the influence of carbonaceous particles with different sizes and shapes on the morphology and mechanical performances of polyamide (PA)-based fibers was investigated. Graphene nanoplatelets (GNP) are compared with spherical and rod-like carbon fillers such as carbon black (CB) and multiwall carbon nanotubes (CNTs). The increments of the complex viscosity as well as elastic and loss moduli, in the melt state, assessed by rheological analysis, are reduced by modifying polyamide (PA) matrix with nanofillers in a following order: CNTs > GNP > CB. All the nanocomposites, however, show viscosity and moduli higher than those of neat PA. The CB loading causes a mere increase of the vi…
On the role of multi-functional polyhedral oligomeric silsesquioxane in polystyrene-zinc oxide nanocomposites
2014
Abstract Multi-functional trisilanol phenyl (TSPH) and trisilanol isobutyl (TSIB) polyhedral oligomeric silsesquioxane (POSS) have been used in the formulation of advanced polystyrene (PS)-zinc oxide (ZnO) nanocomposites. The neat matrix and PS/ZnO-based nanocomposites have been characterized through rheological, morphological, mechanical, and dynamic thermo-mechanical analysis. Both TSPH and TSIB are able to improve the dispersion of ZnO into the polystyrene matrix; furthermore, adding TSIB leads to better results because it facilitates better solubility into the PS matrix and interaction/reaction with the ZnO nanopowder. Finally, the optical properties and photo-oxidative resistance of th…
Gold nanoparticle catalysis of the cis-trans isomerization of azobenzene
2013
Ablated, “pseudo-naked” gold nanoparticles (AuNPs) catalyze the cis–trans isomerization of substituted azobenzenes. para-Substitution was found to affect the rate of isomerization, suggesting the participation of AuNP-mediated electron transfer in the isomerization mechanism. Fil: Hallet Tapley, Geniece. University of Ottawa; Canadá Fil: D'Alfonso, Claudio. University of Ottawa; Canadá. Universita Di Roma; Italia Fil: Pacioni, Natalia Lorena. University of Ottawa; Canadá Fil: McTiernan, Cristopher D.. University of Ottawa; Canadá Fil: Gonzalez Bejar, Maria. University of Ottawa; Canadá. Universidad de Valencia; España Fil: Lanzalunga, Osvaldo. Universita Di Roma; Italia Fil: Alarcon, Emilio…
Physicochemical characterization of octakis(alkyloxy)-substituted Zn(ii)-phthalocyanines non-covalently incorporated into an organogel and their rema…
2007
A series of octakis(alkyloxy)-substituted Zn(II)-phthalocyanines were efficiently incorporated into an organogel made of (1R,2R)-trans-1,2-bis(dodecanoylamino)cyclohexane by means of multiple cooperative non-covalent interactions, and SEM revealed the formation of unique brush-like nanostructures.
Solution-processed thin films based on sandwich-type mixed (phthalocyaninato)(porphyrinato) europium triple-deckers: Structures and comparative perfo…
2012
The solution-processed thin films of a series of three sandwich-type mixed (phthalocyaninato)(porphyrinato) europium complexes with different numbers of hydroxyl groups at the meso-substituted phenyl groups of porphyrin ligand 1–3 were prepared by a quasi-Langmuir–Shafer (QLS) method. Examination by spectroscopic methods revealed that J-type aggregates have been formed with the increasing degree of order of molecular stacking 1 < 2 < 3 films. The IR and XRD results reveal that, a dimeric supramolecular structure was formed depending mainly on the π–π interaction between the tetrapyrrole cores of neighboring triple-decker molecules, which, as the building blocks, self-assembled into the targ…
Spark plasma synthesis from mechanically activated powders: a versatile route for producing dense nanostructured iron aluminides
2004
Abstract The possibility of mechanically activated spark plasma sintering (MASPS) to perform simultaneously within a very short period of time the synthesis and the consolidation of nanophase iron aluminide from mechanically activated powders of Fe and Al in two different ratio (Fe53 at.% and Fe60 at.%) were confirmed in this work.
Mechanical activation effect on the self-sustaining combustion reaction in the Mo–Si system
2001
Abstract Nanostructured molybdenum disilicide (MoSi2) was synthesized using an alternative route called MASHS (mechanically activated self-propagating high-temperature synthesis). This original process combines a short duration ball milling (MA) with a self-sustaining combustion (SHS). These two steps were investigated. The microstructure evolution of the powder mixture during mechanical activation was monitored using XRD profile analysis and TEM investigations. Short duration ball milling of (Mo+2Si) powder produces Mo and Si nanocrystallites into micrometric particles. It was demonstrated that pure α-MoSi2 with nanometric structure (DMoSi2=88 nm) could be produced via a very fast combusti…
Bulk FeAl nanostructured materials obtained by spray forming and spark plasma sintering
2007
Abstract This paper examines the efficiency of two consolidation processing techniques high velocity oxy-fuel (HVOF) spray forming and spark plasma sintering (SPS) which allow to obtain bulk dense nanostructured materials. An oxide dispersion strengthened (ODS) Fe–40Al (at.%) based milled powder (with a nanostructure
Optical biosensors based on ZnO nanostructures: advantages and perspectives. A review
2016
This review article highlights the application of beneficial physico-chemical properties of ZnO nanostructures for the detection of wide range of biological compounds. As the medical diagnostics require accurate, fast and inexpensive biosensors, the advantages inherent optical methods of detection are considered. The crucial points of the immobilization process, responsible for biosensor performance (biomolecule adsorption, surface properties, surface defects role, surface functionalization etc.) along with the interaction mechanism between biomolecules and ZnO are disclosed. The latest achievements in surface plasmon resonance (SPR), surface enhanced Raman spectroscopy (SERS) and photolumi…
Growth and characterization of PbI2-decorated ZnO nanowires for photodetection applications
2020
Financial support provided by Scientific Research Project for Students and Young Researchers Nr. SJZ/2017/1 realized at the Institute of Solid State Physics, University of Latvia is greatly acknowledged. The authors are grateful to Liga Bikse for XRD measurements.