Abstract: A steel contains, by weight: C: 0.3% to 0.5%, Si: 0.1% to 0.5%, Mn: 1% or less, P: 0.03% or less, S: 0.005% or less, Cr: 0.3% to 1%, Mo: 1% to 2%, W: 0.3% to 1%, V: 0.03% to 0.25%, Nb: 0.01% to 0.15%, Al: 0.01% to 0.1%, the remainder of the chemical composition of the steel being constituted by Fe and impurities or residuals resulting from or necessary to steel production and casting processes. The steel can be used to produce seamless tubes for hydrocarbon wells with a yield strength after heat treatment of 862 MPa or more or even 965 MPa or more.

Abstract: A steel contains, by weight: C: 0.3% to 0.5%, Si: 0.1% to 0.5%, Mn: 1% or less, P: 0.03% or less, S: 0.005% or less, Cr: 0.3% to 1%, Mo: 1% to 2%, W: 0.3% to 1%, V: 0.03% to 0.25%, Nb: 0.01% to 0.15%, Al: 0.01% to 0.1%, the remainder of the chemical composition of the steel being constituted by Fe and impurities or residuals resulting from or necessary to steel production and casting processes. The steel can be used to produce seamless tubes for hydrocarbon wells with a yield strength after heat treatment of 862 MPa or more or even 965 MPa or more.

Abstract: An aqueous solution of a hydrophobic/oleophobic agent incorporating a primer of formula: X3SiRSiX3  (I) in which: R represents a carbon chain, and X represents a hydrolysable functional group.

Abstract: The invention relates to a composition for a hydrophobic/oleophobic coating containing at least one alkoxysilane and at least one halosilane, each having a perfluorinated group at at least one end of their molecule; it also relates to a process for forming a coating of this type on a substrate, as well as to this substrate itself when provided with its coating and, in particular, monolithic, laminated or multiple glazing at least in part provided with its coating.

Abstract: Substrate, at least part of at least one of the faces of which has a geometry which is optionally obtained by means of a coating and which differs from that of an ideal uniform, perfectly plane or even slightly curved, sheet, in that it has a bumps-and-hollows relief which can be defined by submicron sizes which, almost in their entirety, fall into at least two different classes, the respective representative values of which vary by a factor of at least 5 or of at most 1/5; applications of this substrate to anti-stain and anti-mist or anti-rain glazing; processes for preparing the substrate.