Abstract: An optical microscope system for reconstructing an image of an object includes a means for creating a light beam profile, an optics for directing the light beam profile to the object, a moving means for implementing a scanning of the object with the light beam profile, a rotating means for enabling rotating the light beam profile and the object, and for changing the direction of scanning, and a detector for measuring the intensity of light passing through or reflected by the object. The image may be tomographically reconstructed using this intensity data associated with various directions as a plurality of projections.

Abstract: The invention is an optical microscope system (1) for reconstructing an image of an object (14), comprising: a means (8) for creating a light beam profile (7), an optics for directing the light beam profile (7) to the object (14), a moving means for implementing a scanning of the object (14) with the light beam profile (7), a rotating means for enabling rotating vis-a-vis each other the light beam profile (7) and the object (14), and for changing the direction of scanning, and a detector (5) for measuring the intensity of light passing through or reflected by the object (14). Further, the invention is a method for reconstructing the image of an object (14) by means of an optical microscope system (1).

Abstract: The invention relates to an improved process for reducing the iron content of iron-, silicon- and aluminium-containing raw materials and for producing ferric oxide, optionally along with an alumina concentrate. According to the invention the iron content of mineral raw materials, e.g. bauxites, clay minerals, colliary rocks, red muds, etc. is eliminated by passing through one or more beds prepared from the unground but preferably prebroaken and sized raw material an aqueous hydrochloric acid solution, the concentration of which exceeds 100 g./lit., at a temperature below 90.degree. C., preferably at room temperature, optionally in the presence of a flocculating agent. By pyrolytic decomposition of the ferric chloride prepared ferric oxide can be produced.

Abstract: The invention concerns a process for the preparation of alumina and ferric oxide from low-grade aluminium and iron carriers. The processes, in addition to conventional technological steps, comprises the steps of dissolving the iron content of a ground, mineral material in an aqueous hydrochloric acid solution containing 200 to 420 g./lit. of hydrochloric acid at 90.degree. to 130.degree. C., eliminating the iron from the slurry of from a solution obtained by filtration of the slurry, with an anion exchange resin or semipermeable membrane or cloth, continuously or discontinuously, eluting the iron from the ion exchange resin and recycling hydrochloric acid and sulfuric acid in a closed system.