The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 08, 2014
Filed:
Mar. 12, 2010
Laïfa Boufendi, Saint Denis en Val, FR;
Gaëtan Wattieaux, Orléans, FR;
Laïfa Boufendi, Saint Denis en Val, FR;
Gaëtan Wattieaux, Orléans, FR;
Centre National de la Recherche Scientifique, Paris, FR;
Universite d'Orleans, Orleans, FR;
Abstract
This invention relates to a method for determining the average surface radius ro and/or the density r of the particles of a nanopowder in a sample levitating in an electropositive plasma with a volume V formed between a first electrode powered by a radiofrequency voltage and a second electrode with a fixed voltage, in particular a ground one, characterized in that: V is the amplitude at the measuring time t of the radiofrequency voltage RF powering the first electrode when the powder is present in the plasma, V is the amplitude of said radiofrequency voltage powering the first electrode in the absence of powder in the plasma, V is the self-polarization voltage of the first electrode at the time t when the powder is present in the plasma, V is the self-polarization voltage of the first electrode in the absence of powder in the plasma, ΔAis the surface variation of the second electrode in the presence of powder at the time t relative to a situation in which powder is absent, and the values of n and K are determined by means of calibrating by tracing a curve in which ro is a function of ΔAand of Vfrom experimental data obtained from powders having a known particle diameter by measuring V, V, V, and Vand by applying a regression to said curve.