Abstract: Process for the chemical vapor deposition by DLI-MOCVD on a substrate of a protective coating composed of at least one protective layer comprising a transition metal M: a) having available, in a feed tank, a mother solution containing a hydrocarbon solvent devoid of oxygen atom and a precursor of bis(arene) type containing the transition metal M to be deposited, and, if appropriate, a carbon-incorporation inhibitor; b) vaporizing said mother solution and introducing it into a CVD reactor in order to carry out the deposition of the protective layer on said substrate; c) collecting, at the outlet of the reactor, a fraction of the gaseous effluent comprising the unconsumed precursor, the aromatic byproducts of the precursor and the solvent, these entities together forming a daughter solution, and; d) pouring the daughter solution thus obtained into the feed tank in order to obtain a new mother solution capable of being used in step a).

Abstract: A process for producing an unsupported molybdenum sulfide nanocatalyst comprising atomizing a molybdenum oxide solution to form a molybdenum oxide aerosol, pyrolyzing the molybdenum oxide aerosol with a laser beam to form the unsupported molybdenum-based nanocatalyst, and pre-sulfiding at least a portion of the unsupported molybdenum-based nanocatalyst to form an unsupported molybdenum sulfide nanocatalyst, wherein the unsupported molybdenum-based nanocatalyst, the unsupported molybdenum sulfide catalyst or both are in the form of nanoparticles with a diameter of 1-10 nm and in a distorted rutile crystalline structure. A method of selective deep hydrodesulfurization whereby a hydrocarbon feedstock having at least one sulfur-containing component and at least one hydrocarbon is contacted with the unsupported molybdenum sulfide nanocatalyst.

Abstract: A process for producing an unsupported molybdenum sulfide nanocatalyst comprising atomizing a molybdenum oxide solution to form a molybdenum oxide aerosol, pyrolyzing the molybdenum oxide aerosol with a laser beam to form the unsupported molybdenum-based nanocatalyst, and pre-sulfiding at least a portion of the unsupported molybdenum-based nanocatalyst to form an unsupported molybdenum sulfide nanocatalyst, wherein the unsupported molybdenum-based nanocatalyst, the unsupported molybdenum sulfide catalyst or both are in the form of nanoparticles with a diameter of 1-10 nm and in a distorted rutile crystalline structure. A method of selective deep hydrodesulfurization whereby a hydrocarbon feedstock having at least one sulfur-containing component and at least one hydrocarbon is contacted with the unsupported molybdenum sulfide nanocatalyst.

Abstract: Method for preparing carbon nanotubes or nitrogen-doped carbon nanotubes by pyrolysis, in a reaction chamber, of a liquid containing at least one liquid hydrocarbon precursor of carbon or at least one liquid compound precursor of carbon and nitrogen consisting of carbon atoms, nitrogen atoms and optionally hydrogen atoms and/or atoms of other chemical elements such as oxygen, and optionally at least one metal compound precursor of a catalyst metal, in which said liquid is formed under pressure into finely divided liquid particles such as droplets by a specific injection system, preferably a periodic injection system, and the finely divided particles, such as droplets, formed in this way are conveyed by a carrier gas stream and introduced into the reaction chamber, where the deposition and growth of the carbon nanotubes or nitrogen-doped carbon nanotubes take place.

Abstract: Method for preparing carbon nanotubes or nitrogen-doped carbon nanotubes by pyrolysis, in a reaction chamber, of a liquid containing at least one liquid hydrocarbon precursor of carbon or at least one liquid compound precursor of carbon and nitrogen consisting of carbon atoms, nitrogen atoms and optionally hydrogen atoms and/or atoms of other chemical elements such as oxygen, and optionally at least one metal compound precursor of a catalyst metal, in which said liquid is formed under pressure into finely divided liquid particles such as droplets by a specific injection system, preferably a periodic injection system, and the finely divided particles, such as droplets, formed in this way are conveyed by a carrier gas stream and introduced into the reaction chamber, where the deposition and growth of the carbon nanotubes or nitrogen-doped carbon nanotubes take place.

Abstract: The invention relates to a process for the preparation of a multilayer coating, comprising a stack, on a substrate, of several layers chosen from among layers constituting by TiN and layers constituted by (Ti,Al)N, also known as Ti.sub.1-x Al.sub.x N, the entire coating being produced in a single, continuous operation by thermal chemical vapour deposition (CVD) from a gaseous mixture comprising a reducing gas, such as ammonia or nitrogen, hydrogen and titanium and optionally aluminium chlorides, the nature and/or composition of each deposited layer being instantaneously adjusted by modifying the reducing gas to hydrogen molar ratio in the gaseous mixture. The invention also relates to multilayer coatings comprising (Ti,Al)N layers of variable compositions and in particular with composition gradient. Application to wear-resistant or abrasion-proof coatings having a resistance to oxidation and corrosion, particularly at high temperatures.

Abstract: The subject of the invention is a process of continuous coating, with a polymer deposition, of a metallic material in motion inside a chamber under a reduced pressure, in which process the monomer of the said polymer is injected, in the gaseous state, into the said chamber and the conditions for forming a cold plasma are created so as to cause coating of the said material with the said polymer deposition, which comprises, in at least one region of the said chamber, the said material being made to pass through a magnetic field so as to cause a variation in the composition of the said polymer deposition in the said region. The subject of the invention is also a device for the implementation of this process, and a product obtained thereby.

Abstract: The object of the invention is a one-step deposition process of a coating of the ceramic type based on nitrides or carbonitrides of at least one metallic element selected from Cr, V, Zr, W, Mo, Co, Mn, Ni, Hf and Ta on a metallic or ceramic substrate, massive or obtained from fibres, by deposition in the vapor phase wherein a coating is deposited on the substrate by a chemical means at a pressure lower than 10 kPa at a temperature lower than 600.degree. C. and by using a system of precursors constituted simultaneously of:an organo-metallic precursor of the said metallic element selected from the organo-metallic compounds of the sandwich type of general formula:[Ar.sup.1 M Ar.sup.2.sub.n ]L.sub.x L'.sub.ya nitrogen precursor selected from ammonia and hydrazine.