Abstract: A heterogeneous catalyst is described, active in the metathesis reaction of olefins comprising alumina as inert carrier and a rhenium compound as active component, characterized in that rhenium is present in an amount of less than 5% by weight with respect to the total preferably from 1 to 4% by weight, and the inert carrier is impregnated with at least one inorganic halide selected from FeCl3, CuCl2, TiCl4, RuCl3, ZnCl2 and NH4Cl, and/or the corresponding bromides or iodides and, subsequently, treated at a high temperature.

Abstract: A sealing technique is provided for forming complex and multiple seal configurations for fuel cells and other electrochemical cells. To provide a seal, for sealing chambers for oxidant, fuel and/or coolant, a groove network is provided extending through the various elements of the fuel cell assembly. A source of seal material is then connected to an external filling port and injected into the groove network, and the seal material is then cured to form the seal. There is thus formed a “seal in place”, that is robust and can accommodate variations in tolerances and dimensions, and that can be bonded, where possible, to individual elements of the fuel cell assembly. A release agent can be applied on the surface of fuel cell components or added to the seal material to enable the fuel cell stack to be easily disassembled and defective cells to be repaired without discarding the whole fuel cell stack.

Abstract: The present invention provides for a terminal plate for an electrochemical cell. The terminal plate is a metal plate having at least one manifold region with at least one aperture to permit the passage of a fluid therethrough. The terminal plate has a corrosion resistant coating applied to at least a portion of the at least one manifold region including the at least one aperture. A method for producing the terminal plate is also disclosed. A method for producing a fuel cell stack is also disclosed.

Abstract: The present invention provides for an end plate for an electrochemical cell. The end plate is a metal plate having at least one manifold region with at least one connection port to permit the passage of a fluid therethrough. The nd plate has a corrosion resistant coating applied to the at least one manifold region including the at least one connection port. A method for producing the end plate is also disclosed.

Abstract: Process for the preparation of manufactured products based on vinylaromatic polymers with a predominantly syndiotactic structure which comprises:a) compressing the polymer in powder form in a mould at a pressure ranging from 0.1 to 500 MPa;b) sintering, under pressure, the compact powder at a temperature ranging from the glass transition temperature (Tg) of the polymer to the melting temperature (Tm);c) cooling the manufactured product to room temperature.

Abstract: Polyethyleneterephthalate (PET) originating from the sorted collection of solid urban refuse can be regraded and recycled as such or mixed with virgin PET if treated at high temperature with an oxazoline of general formula: ##STR1##

Abstract: Alpha-alumina consisting essentially of solid, spherical, non-aggregated particles, having a diameter from 0.06 to 2 .mu.m, a polydispersion index below 2.0, a total porosity below 0.3 cc/g, a specific surface area from 0.7 to 80 m.sup.2 /g, and an apparent density of the particles from 3.20 to 3.94 g/cm.sup.3. The alpha-alumina is prepared by a process consisting, in that an alpha-alumina precursor, having a water content from 2 to 33% by weight, at starting temperatures ranging from room temperature to 850.degree. C., and consisting essentially of solid spherical, non-aggregated particles, having a particle diameter from 0.07 to 2.3 .mu.m and a polydispersion index of .ltoreq.2.0, is subjected to a heat-treatment at temperatures ranging from 1130.degree. to 1700.degree. C., said precursor being instantaneously brought from the starting temperature to the treatment temperature, and by carrying out the treatment during times, as generally indicated in the accompanying FIG.

Abstract: A process for preparing iron-based catalysts for the synthesis of ammonia by melting of magnetite along with metal oxides as promoters, subsequent cooling of the molten mass and reduction thereof to the desired size, wherein the abovesaid cooling occurs at a rate higher than 25.degree. C./min., preferably ranging from 100.degree. C. to 1600.degree. C./min., at a temperature ranging from 1700.degree. C. to 700.degree. C.The present invention relates to a process for preparing iron-based catalysts having a high activity in the ammonia synthesis, and to the catalyst so obtained.