Abstract:
Methods of synthesizing nanoparticles of an isotope using a laser beam are described herein. The methods include generating the laser beam, directing the laser beam to the target to convert the target into a plasma state, and bombarding the target in the plasma state with the laser beam to maintain the target in the plasma state and synthesize the nanoparticles of the isotope. During bombarding the target in the plasma state with the laser beam, the laser beam is configured to have a pulse frequency and peak laser intensity that accelerates electrons in the plasma state and maintains the plasma state at a temperature high enough to provide for the synthesis of the nanoparticles of the isotope. Apparatuses for synthesizing nanoparticles of an isotope using a laser beam are also described herein.
Abstract:
La présente invention concerne un procédé de préparation de nanoparticules d'or pentamaclées comprenant au moins les étapes suivantes : i) fournir une suspension de germes d'or comprenant des germes d'or, un agent tensioactif cationique et au moins un solvant inerte, la température de ladite suspension étant comprise entre 30 et 75°C; ii) fournir une solution de croissance comprenant un sel d'or, un agent tensioactif cationique, un agent réducteur, ledit agent réducteur étant un composé aromatique comprenant au moins un noyau aromatique porteur d'au moins un groupe hydroxyle, et optionnellement au moins une base; iii) soumettre la suspension de germes d'or de l'étape i) à un traitement de croissance comprenant les étapes suivantes : iii 1 ) ajouter de façon contrôlée la solution de croissance de l'étape ii) dans la suspension de germes d'or de l'étape i); iii 2 ) maintenir la température du mélange obtenu à l'étapeiii 1 ) à une température comprise entre 30°C et 75°C pendant au moins 5 minutes. L'invention a également pour objet une nanosuspension susceptible d'être obtenue selon le procédé de l'invention, et son utilisation pour la fabrication d'un capteur optique.
Abstract:
The invention relates to a process for preparing single-crystal thin films of pure metals or alloys, by deposition and growth of grains on a (0001) sapphire having a miscut comprised between 0.2° and 5°, and oriented towards a specific plane. It also relates to a single-crystal thin film obtainable by such a process and uses thereof.
Abstract:
A method for depositing a layer of graphene directly on the surface of a substrate, such as a semiconductor substrate is provided. Due to the strong adhesion of graphene and cobalt to a semiconductor substrate, the layer of graphene is epitaxially deposited.
Abstract:
The invention is related to a method of producing graphene by deposition of carbon from gaseous phase on a substrate in a reactor, comprising following steps: a) providing the substrate in the reactor; b) providing elevated temperature conditions in the reactor; c) providing lower pressure conditions in the reactor; d) evoking a flow of a gas in the reactor, said gas comprising at least a carbon precursor gas mixed with an inert gas and optionally mixed with hydrogen; e) under such conditions of the elevated temperature, the lower pressure and the gas flow - depositing carbon from the gaseous phase on the substrate thus forming graphene; characterized in that a wafer having a crystalline layer of germanium having the crystallographic orientation (100) intended for graphene deposition thereon is used as the substrate.
Abstract:
A method of making an ordered graphene structure includes exposing a substrate to a laser beam to locally melt a portion of the substrate, exposing the substrate to a laser beam in the presence of a carbon source, to form a nucleation site for a graphene crystal, and either a) moving either the substrate or the laser beam relative to the other, or b) decreasing the laser beam power, in order to increase the size of the graphene crystal, thereby forming an ordered graphene structure. The ordered structure can be a plurality of columns, hexagons, or quadrilaterals. Each ordered structure can have a single crystal of graphene. A polymer coating can be formed on the ordered graphene structure to form a coated graphene structure.
Abstract:
Methods for growing microstructured and nanostructured graphene by growing the microstructured and nanostructured graphene from the bottom-up directly in the desired pattern are provided. The graphene structures can be grown via chemical vapor deposition (CVD) on substrates that are partially covered by a patterned graphene growth barrier which guides the growth of the graphene.
Abstract:
A process for manufacturing magnetic and/or radioactive metal nanoparticles, the process comprising: preparing an electrolyte solution including metal ions and a stabilizer; generating a plasma at an interface of the electrolyte solution at atmospheric pressure; and recovering magnetic and/or radioactive metal nanoparticles. The magnetic metal nanoparticles can comprise magnetoradioactive nanoparticles. The magnetic metal nanoparticles can be used as MRI contrast agents and the magnetoradioactive nanoparticles can also be used as contrast agents and for dual PET/MRI applications. It also relates to a multi-plasma apparatus for synthesizing nanoparticles.