Abstract: There is provided a process for manufacturing a carbonaceous anode for an electrolysis cell for the production of aluminium. The process comprises contacting coke particles with a boron-containing solution to obtain boron-impregnated coke particles, mixing the boron-impregnated coke particles with coal tar pitch to form an anode paste, and forming a green anode with the anode paste. A carbonaceous anode for an electrolysis cell for the production of aluminium is also provided, which comprises at least a first fraction of coke particle, a second fraction of coke particles and coal tar pitch, wherein at least the first faction of coke particles comprises boron-impregnated coke particles, the boron-impregnated coke particles being distributed throughout the carbonaceous anode. The carbonaceous anode presents good resistivity towards air and CO2 oxidation, which translates into less dusting of the anode, thus improving its integrity throughout its lifetime.

Abstract: The present invention relates to a process for producing an activated perovskite-based washcoat formulation suitable for reduction of carbon monoxide, volatile organic compounds, particulate matter, and nitrogen oxides emissions from an exhaust gas stream. The process includes the steps of high energy ball milling a fully synthesized perovskite structure to provide an activated nanocrystalline perovskite powder of a given surface area; mixing the activated nanocrystalline perovskite powder with dispersing media and grinding the mixture; removing partially or totally the dispersing media to obtain an activated perovskite-based catalyst washcoat formulation wherein the activated perovskite in the formulation has a specific surface area greater than that of the activated nanocrystalline perovskite powder. The process may further include a step of applying the formulation on a substrate to obtain a catalytic converter.

Abstract: The invention is concerned with a method of forming a single crystal of a ceramic, semiconductive or magnetic material. The method according to the invention comprises the steps of (a) compacting a nanocrystalline powder comprising particles having an average particle size of 0.05 to 20 &mgr;m and each formed of an agglomerate of grains with each grain comprising a nanocrystal of a ceramic, semiconductive or magnetic material; and (b) sintering the compacted powder obtained in step (a) at a temperature sufficient to cause an exaggerated growth of at least one of the grains, thereby obtaining at least one single crystal of aforesaid material.

Abstract: The invention relates to a ceramic material in powder form comprising particles having an average particle size of 0.1 to 30 &mgr;m and each formed of an agglomerate of grains with each grain comprising a nanocrystal of a ceramic material of formula (I): Si3-xAlxOyNz, wherein 0≦x≦3, 0≦y≦6 and 0≦z≦4, with the proviso that when x is 0 or 3, y cannot be 0. The ceramic material in powder form according to the invention is suitable for use in the production of ceramic bodies by powder metallurgy, as well as in the formation of heat-resistant coatings by thermal deposition. The ceramic bodies and coatings obtained have improved resistance to thermal shocks.

Abstract: The invention concerns novel varistors based on zinc oxide and a method for making same, which consists in using as base products nanocrystalline powders obtained by high-intensity mechanical grinding and in subjecting the mixture resulting from said nanocrystalline powders a consolidating treatment such as sintering, in suitably selected temperature and time conditions so as to retain the smallest possible grain size of ZnO. The resulting varistors have a very fine homogeneous microstructure and an average grain size characteristically not more than 3 mu m, i.e. five times smaller than standard materials. Said novel varistors have a larger number of grain boundaries per length unit and therefore a much higher breakdown voltage. Said voltage is characteristically higher than 10 kV/cm and can reach 17 kV/cm which is almost one order of magnitude above the breakdown voltage of standard varistors.