Abstract:
This invention is directed to novel and useful process for the preparation of boron carbide, boron nitride and silicon carbide comprising carbidization or nitrization step of boron oxides or silicon oxides, using nanoparticles substrates.
Abstract:
This invention is directed to a process for the preparation of boron nitride powder, particularly a fine powder with a low degree of contamination, which demonstrates good caking, heat conductivity and dielectric properties. Specifically, a process for the preparation of amorphous boron nitride (a-BN) is provided wherein the process comprises: mixing powders of boric acid and a carbamide at a temperature in the range of about 250-300°C, thereby forming: ammonium polyborates; boron imide or a mixture thereof and ammonia; and heating of the materials formed in step (a) to a temperature in the range of about 500-600°C, thereby forming a powder of a-BN.
Abstract:
A magnetocontrollable carrier with a physiologically active substance consisting of ferrocarbon particles containing 10 to 90 % iron, the balance being carbon. The particles have adsorption capacity of no less than 6 mg/g on methylene blue and contain the physiologically active substance adsorbed on them. A method for making said carrier with a physiologically active substance provides for heating the iron powder in an oxidizing medium at a temperature of 800-1200 DEG C, and then treating it with carbon monoxide at a temperature of 400-700 DEG C until ferrocarbon particles are obtained which are introduced into a solution of the physiologically active substances, which are then adsorbed on the surface of said particles.
Abstract:
This invention is directed to novel and useful process for the preparation of boron carbide, boron nitride and silicon carbide comprising carbidization or nitrization step of boron oxides or silicon oxides, using nanoparticles substrates.
Abstract:
The present invention relates to a catalyst used in the low-temperature pyrolysis of hydrocarbon-containing polymer materials, said catalyst being mainly intended for use in the recycling of rubber waste materials. The catalyst is prepared from a carbon-iron component in the form of microscopic carbon particles and ultra-dispersed iron particles. In order to increase the yield of light hydrocarbon fractions in the condensate and to bind substantially completely the sulphur in the products of the rubber pyrolysis, the catalyst further contains a metal-carbon component. This component consists of the product from the stripping and the pyrolysis of a dispersion that comprises at least one salt of a metal from the group VIII in the periodic table which is capable of decay upon heating in order to form an oxide, wherein said metal is selected from the group comprising iron, nickel and cobalt. The dispersion further includes a carbohydrate as well as a highly volatile solvent.