Abstract: Silicon carbide foam useful as a catalyst support has a BET specific surface area of at least 5 m2/g, and a compression strength exceeding 0.2 MPa. The foam is prepared by impreganting an organic foam with a suspension of silicon in a resin containing a cross-linking agent, incompletely cross-linking the resin, carbonizing the foam and resin, and carburizing the silicon.

Abstract: The invention relates to a silicon carbide or metal carbide foam to be used as a catalyst or catalyst support for the chemical or petrochemical industry or for silencers, as well as the process for producing the same. The foam is in the form of a three-dimensional network of interconnected cages, whose edge length is between 50 and 500 micrometres, whose density is between 0.03 and 0.1 g/cm3 and whose BET surface is between 20 and 100 m2/g. The carbide foam contains no more than 0.1% by weight residual metal and the size of the carbide crystallites is between 40 and 400 Angstroms. The production process consists of starting with a carbon foam, increasing its specific surface by an activation treatment using carbon dioxide and then contacting the thus activated foam with a volatile compound of the metal, whose carbide it is wished to obtain.

Abstract: Catalyst support in granular form with a SiC&bgr; crystallite base and a high specific surface area having improved mechanical characteristics. The porosity of the support is between 0.001 and 1 um in size and the crystallinity of the support is determined by: a full width at half maximum of diffraction X rays, corresponding to plane [2 2 0] of the SiC&bgr; crystallites, of between 0.15 and 0.60°, angle 2&thgr; of Bragg's law; and a bidimensional peak height [1 0] corresponding to directions [1 0] normalized by the integrated intensity of the peak of plane [2 2 0] of between 0.15 and 0.40.

Abstract: SiC foam-based catalyst carrier in the form of a moulded part having walls reinforced with a SiC skin having mechanical characteristics higher than those of the foam, this skin allowing the carrier to be handled and used without damage.

Abstract: A heat sealed, easy-opening and reclosable package, which comprises a packaging material comprised of a heat sealable base member material, and an elongate, multilayer, flexible, peelable and reclosable strip positioned between the surfaces of juxtaposed portions of base member material and comprised of an interior tacky adhesive layer, a first and second surface sealant layers, the strip including a rupturable layer proximate the tacky adhesive layer. The base member material is heat sealed together along and by means of the strip whereat the sealant layers of the strip are heat sealed to the base member. The heat seal has sufficient initial seal strength to remain closed during handling of the package and yet is manually readily openable and reclosable.

Abstract: A packaging material suitable for forming a heat sealable, easy-opening and reclosable package is comprised of a heat sealable base member material having a first heat sealable surface and, secured to the heat sealable surface, an elongate, heat sealable, multilayer, flexible, peelable and reclosable, preferably coextruded, strip comprised of an interior tacky adhesive layer, first and second sealant layers each comprised of heat sealable polymer, and a rupturable layer, preferably comprised of an ionomer, proximate the tacky adhesive layer. One of the strip sealant layers is secured to the first heat sealable surface of the base member. The strip enables the base member to be heat sealed along and by means of the strip to form a package whose heat seal has sufficient initial seal strength to remain closed during handling and yet can be manually readily opened and reclosed.

Abstract: An electrode for electrophoretic deposition on an electrically conductive surface is formed with a conductive cylindrical tube or solid cylinder. The invention describes coating only the outer lateral surface with an insulating coating, except for one or more annular zone(s) situated facing the object to be coated. The result obtained is a thin deposit which is as uniform as possible.

Abstract: A process is disclosed for the production of cast cylinder heads made of aluminium alloys from at least two different "liquid" alloys. The liquid alloys at the time of casting may contain solid particles of varied size and shape so as to produce composites with a metal matrix after solidifying. The process for moulding composite cylinder heads includes a number of successive layers consisting of at least two different alloys and consists in casting each alloy layer in the cavity of a mould via a feed system with a waiting time between the end of casting of one layer and the beginning of the second layer, so that the first layer contains between 50 and 100% of solid fraction in its lower part and 0 to 80% of solid fraction in the upper part, the interface region, when the second alloy is introduced.

Abstract: A process for isomerizing straight chain hydrocarbons having at least seven carbon atoms by forming a reaction mixture including at least one of the straight chain hydrocarbons and hydrogen and passing the reaction mixture over a catalyst including a molybdenum compound, at least the surface of which is formed of molybdenum carbide partially oxidized in the form of at least one oxycarbide.

Abstract: AA 7000 series alloys having high mechanical strength and a process for obtaining them. The alloys contain, by weight, 7 to 13.5% Zn, 1 to 3.8% Mg, 0.6 to 2.7% Cu, 0 to 0.5% Mn, 0 to 0.4% Cr, 0 to 0.2% Zr, others up to 0.05% each and 0.15% total, and remainder Al. Either wrought or cast alloys can be obtained, and the specific energy associated with the DEA melting signal of the product is lower than 3 J/g.

Abstract: A catalyst for chemical and petrochemical reactions and a process for its production. The catalyst comprises an oxide of one of the transition metals, rare earth elements, or actinide elements, e.g., molybdenum, having on its surface carbides and oxycarbides, the core being the metal or the metal oxide. In the process for catalyst production, the reaction gas mixture containing carbon products is passed onto the oxide, leading to a progressive carburization of the surface of the oxide and to a progressive increase in the efficiency of the catalyst.

Abstract: The disclosure teaches a method for obtaining porous solids of refractory carbide with a large specific surface area. An exclusively organic, polymeric and/or copolymerizable compound, for example a resin, which can be coked and to provide a solid carbon skeleton, is mixed with a powder of metal, or metalloid, or a compound thereof which can be reduced by carbon. The mixture is shaped, the organic compound is cross-linked or hardened, and the compound is heat treated from 500.degree. to 1000.degree. C. to coke it, then heat treated to carburize it.

Abstract: The invention concerns a process for preparing a silicon carbide foam consisting of attacking a polyurethane foam with an alkaline solution, impregnating it, after rinsing and drying, with a suspension of silicon powder in an organic resin, heating progressively to polymerise the resin, carbonising the polyurethane foam and resin, and finally carburising the silicon contained in the resin suspension by means of the carbon originating from the carbonisation of the foam and resin.The foams obtained are characterised by a high microporosity and a mesoporosity which is variable according to the carburising temperature.The invention finds an application in the manufacture of catalyst carriers for exhaust chambers and filters for diesel engines.

Abstract: An apparatus for cleaning, rinsing and coating a metal can body comprising a tank for containing a liquid, an electrically conductive nozzle maintained in a substantially vertical direction and means for supporting a can body inverted over the nozzle. An electrical contact is disposed in an upper portion of the tank directly above the nozzle and the can body is free to move upwardly between the nozzle and the electrical contact under the force of liquid flowing through the nozzle.

Abstract: A process for preparing a silicon carbide foam by impregnating a polyurethane foam with a suspension of silicon powder in an organic resin, heating progressively to polymerize the resin, heating further to carbonize the polyurethane foam and resin, and finally further heating to carburize the silicon contained in the resin suspension by means of carbon obtained from the carbonization of the foam and resin. The foam obtained is characterized by high macroporosity and a mesoporosity which is variable according to the carburizing temperature.

Abstract: A process for the production of a metal carbide having a BET specific surface area of 10 to 200 m.sup.2 /g, in which a reaction mixture including carbon having a specific surface area of at least 200 m.sup.2 /g and a compound of the metal to be reacted with the carbon which is volatile at 900.degree. C. to 1400.degree. C. is introduced into a reactor, the reactor is scavenged by a flow of inert gas and the reaction mixture is heated under the flow of inert gas at 900.degree. to 1400.degree. C. for a time sufficient to volatilize the metal, reduce the volatilized metal compound to the metal with and carburize the metal by reaction with carbon, forming the metal carbide. The metal carbide formed is cooled under the flow of inert gas.

Abstract: The invention relates to a coating for protecting materials against reactions with atmosphere at high temperatures. The coating according to the invention comprises a mixture of zirconium diboride and colloidal silica, advantageously with various additives such as silicon carbide. The coating according to the invention can, for example, efficiently protect carbon and graphite up to 1350.degree. C.

Abstract: There is disclosed a core mix and a method of fabricating the core for use in investment casting. The core composition comprises an acid soluble borate binder in a high percentage by weight of the composition. A refractory selected from period three nitride compounds is employed with the binder to impart strength to the core. The use of the combination of binder and refractory as disclosed herein provides a high strength core which is readily soluble by mild environmentally friendly acids.

Abstract: A process for obtaining bimaterial parts by casting an aluminum alloy onto an insert coated with a metal film. In this process, the oxide layer is removed from the insert by treatment under vacuum, and then the insert is coated with a titanium based film by physical vapor deposition, and the insert is placed in a mold which is filled with a casting alloy.

Abstract: A contactor for the transfer of matter and heat between gas and liquid comprising a helical support of heat conductive material allowing the flow of a liquid to be treated, a wall of heat conductive material and in thermal contact with the said support, separating in sealing-tight manner the said liquid and a heat exchanging fluid, characterized in that the said support and the said wall are formed by a vertical stack of open work plates of a heat conductive material, offset angularly in respect of one another by rotation according to the axis of the said support, each plate thus forming an element of the said support, like a step of a spiral staircase, and an element of the said wall, in such a way as to obtain an economical and efficient evaporator or absorber.