Abstract: A process for preparing a solid composite electrolyte comprising at least one compound of the BIMEVOX family is provided. The process comprises at least one step of preparing a mixture of one or more compounds of the BIMEVOX family with one or more chemically inert compounds, at least one step of compacting the mixture obtained, and at least one sintering step during which the temperature reached, over a nonzero time interval, has a value greater than the optimum sintering temperature for the compound of the BIMEVOX family.

Abstract: Process for separating oxygen from a gas mixture containing it employs a solid-electrolyte electrochemical cell, where the cell includes a homogeneous structure of one or more BIMEVOX derivatives, with dynamic electrodes created "in situ" that are reversible and self-adaptive, and at least two current collectors.

Abstract: The invention relates to ceramic materials usable as tritium producing material in a thermonuclear fusion reactor. These materials are constituted by lithium zirconate substituted by copper in the form of solid solutions of the type Li.sub.2 ZrO.sub.3.

Abstract: A composite structure comprising:(i) a solid electrolyte which is an O.sup.2- anion conductor and essentially impermeable to gases;(ii) a cathode; and(iii) an anode, wherein the cathode and anode are porous to gases and wherein the electrolyte is in contact with the cathode and anode,wherein at least one of the cathode and anode is a voluminal electrode comprising (a) at least one BIMEVOX compound and (b) an electronic conductor, forming a distinct solid phase, dispersed in the BIMEVOX compound so as to define, within respective volumes of the voluminal electrode, a plurality of triple contact points between an ambient gaseous atmosphere, the electrolyte, and the electronic conductor.

Abstract: The present invention relates to an electrochemical cell comprising a solid electrolyte conductive for O.sup.2- anions in contact with an anode and a cathode of identical or different composition, the electrolyte solid being comprised of a composition derived from Bi.sub.4 V.sub.2 O.sub.11 of which at least one of the cationic constituent elements is substituted by at least one substituting element chosen such that the gamma phase structural type of Bi.sub.4 V.sub.2 O.sub.11 is maintained, as well as the equilibrium of charges, at least one of the anode or the cathode including two parts, a first part being of a mixed electronic and ionic conductive material in contact with the solid electrolyte, the second part being an electronic conductive material superposed on the first part. The invention equally relates to the use of the electrochemical cell with a view towards the separation or the extraction of oxygen.

Abstract: The present invention relates to an electrochemical cell comprising a solid electrolyte which conducts O.sup.2- anions in contact with an anode and a cathode of identical or different composition, the solid electrolyte being comprised of a composition derived from Bi.sub.4 V.sub.2 O.sub.11 of which at least one of the constituent cationic elements is substituted by at least one substituting element such that the gamma phase structural type of Bi.sub.4 V.sub.2 O.sub.11 is maintained as well as the equilibrium of charges, at least one of the anode or of the cathode is a material containing at least one element of substitution of said composition derived from Bi.sub.4 V.sub.2 O.sub.11, that element being in a metallic or cationic state. The invention equally relates to the use of the electrochemical cell with a view towards the separation or extraction of oxygen.

Abstract: A stack of parts, such as the stator disks of a turbomolecular pump, the parts being stacked alternately with spacers, includes a spacer having a knife-shaped deformable portion. When the stack is installed for the first time, the portion is compressed so as to take up the tolerances of the stack between abutment surfaces, e.g. delimited by a pump body and a corresponding casing. The invention applies in particular to turbomolecular pumps and aims to eliminate the operations of adjustment, re-machining, or matching that are usually required when installing a stator assembly.

Abstract: The compositions are derived from Bi.sub.4 V.sub.2 O.sub.11 and are characterized by the fact that at least one of the elements present is substituted, the substituting element(s) being such that the structural nature of the gamma phase of Bi.sub.4 V.sub.2 O.sub.11 is maintained, as well as the equilibrium of the loads.