Abstract: The invention relates to a method for the preparation of metallic oxides. The method is carried by controlled hydrolysis of metallic alkoxides using an alkoxide emulsion which contains hydrophobic water/solvent reverse micelles and a surfactant, then submitting the polymer gel obtained to thermal treatment. In order to prepare metallic oxides layers, the reaction product is coated on a support when hydrolysis is only partial.

Abstract: Chemical conversion bath with zinc characterized by the fact that it comprises, besides the conventional constituents, an effective amount of fluorophosphate ion of the formula:F--PO.sub.3.sup.2-which can be introduced in the form of the corresponding acid, one of its alkali, alkaline-earth or ammonium salts or its zinc salt.

Abstract: This invention relates to a corrosion inhibitor for protecting metallic surfaces which are in contact with water, in particular circuits, apparatus and devices which use water as energetic or thermic fluid, said corrosion inhibitor being a fluorophosphate compound selected from the group consisting of:(i) compound of the formula M.sub.2.sup.I PO.sub.3 F, xH.sub.2 O(ii) compound of the formula LiM.sup.I PO.sub.3 F, xH.sub.2 O(iii) compound of the formula NaM.sup.I PO.sub.3 F, xH.sub.2 O(iv) compound of the formula M.sup.II PO.sub.3 F, xH.sub.2 O(v) compound of the formula M.sub.2.sup.I M.sup.II (PO.sub.3 F).sub.2, xH.sub.2 O(vi) compound of the formula M.sup.I PO.sub.2 F.sub.2, xH.sub.2 O(vii) compound of the formula M.sup.II (PO.sub.2 F.sub.2).sub.2, x H.sub.2 O(wherein M.sup.I is Na, K, Rb, Cs or HN.sub.4 ; M.sup.II is Mg, Ca, Ba, Sr, Zn, Cd, Mn, Ni or Co; and x is an integer or a fractional number comprised between 0 and 6) and(viii) mixtures thereof.

Abstract: The present invention relates to a method of manufacturing a medium for microfiltration, for ultrafiltration, or for reverse osmosis, wherein hydrolysis is performed on an alkoxide, an organo-metallic compound, or a metal salt of an organic or an inorganic acid, optionally dissolved in an anhydrous organic solvent, in order to obtain a sol of particles of the oxide or of the hydroxide of the corresponding chemical element, a thickening agent is added to the sol, and the resulting sol is slip cast onto a support layer having pores which are larger than pores desired for the filter medium, the thin layer deposited on the support medium is then dried, and then heat treated to eliminate the thickening agent and to sinter the particles of the deposited thin layer. The thickening agent is added to the sol in conjunction with a strong acid whose anion does not form a complex with ions of the oxide or hydroxide metal, and the slip casting is performed by mere putting into contact without filtering.

Abstract: Structure of the insulator--semiconductor type constituted by a semiconducting crystalline substrate formed from a III-V compound of formula (A.sup.III B.sup.V) coated with an insulating layer, wherein the substrate has a specific crystalline orientation and wherein the insulator is a sulphide in accordance with the formula (A.sup.III B.sup.V)S.sub.4.It also relates to a process for the preparation of such a structure.Applications of the invention occur in the fields of microelectronics and optoelectronics.

Abstract: Steel, aluminum and aluminum alloys, zinc and zinc alloys are treated to improve corrosion resistance with an aqueous solution of a fluorophosphate salt to passivate the metal surface, before or after phosphatizing and prior to painting.

Abstract: Steel, aluminum and aluminum alloys, zinc and zinc alloys are treated to improve corrosion resistance with an aqueous solution of a fluorophosphate salt to passivate the metal surface, before or after phosphatizing and prior to painting.