Abstract: The invention concerns a gaseous flux laser device. To enable the removal into the atmosphere of the exhaust gases of an N.sub.2 -CO.sub.2 laser while maintaining a sufficiently low pressure in the zone where the stimulated light emission occurs, the carbon dioxide is injected through supersonic nozzles and an exhaust tube having a sufficient length is used. Application to the generating of powerful coherent light beams.

Abstract: A porous metal body, e.g. an electrode for an electric cell, is prepared using the following steps:preparing a foam by adding a surface active agent and a gelling agent to water and then foaming the mixture by stirring and/or blowing air through it;incorporating metal powder in the foam in order to obtain a suspension of the metal therein;shaping the foam with its suspension of metal, and adding a stabilizing agent thereto, said stabilizing agent being one which polymerizes on contact with water, thereby causing the shaped foam to set in shape; andheating the set foam to pyrolize the organic material therein and to sinter the metal.This method produces a more even and a more reliable pore size than has previously been possible.

Abstract: Mode coupling using grating of ridges and furrows to curve the fibre along a zig-zag path are associated with an index matcher which surrounds the fibre. The average axis of the zig-zag fibre coincides that of the matcher. Light travels along lines all at the same angle to the axis of the matcher and pass through via a conical optical end surface thereof. The optical surface converts the said rays into a parallel beam for coupling with large aperture optical means such as a photo-cell or a LED.

Abstract: Fibre-retaining grooves are formed in-between a set of fibre locating pins (M) laid side by side. The pins and a base plane (4) on which they are laid are made of hard, rigid material. Guidance for connection and disconnection is provided by guide pins (G1 to G4) of larger diameter which are therefore robust enough to stand up to handling. The guide pins are in direct contact with the locating pins in order to ensure positional accuracy.

Abstract: An amorphous cationic conductor of lithium comprising a composition corresponding to the general formula:{B.sub.2 O.sub.3, xM, yN} , aLi.sub.2 O, bLi.sub.z Q 11in which:M is chosen from the group formed by:Al.sub.2 O.sub.3, V.sub.2 O.sub.5, P.sub.2 O.sub.5, As.sub.2 O.sub.5 As.sub.2 O.sub.3 ;N is chosen from the group formed by:SiO.sub.2 and GeO.sub.2 ;Q is chosen from the group formed by halogen anions and bi- or tri-valent mono- or poly-atomic anions exclusive of O.sup.2- ;O.ltoreq.x.ltoreq.0.35;O.ltoreq.y.ltoreq.0.8;O<a.ltoreq.2;O<b<1.5;b.ltoreq.2a; andz=1 or 2 or 3 according to whether Q is mono-, bi- or tri-valent.

Abstract: A gas laser device includes, in succession along an optical axis, a gas laser excited by a travelling wave, a convergent lens, two parallel-sided optical prisms adhering to one another in a symmetrical position in relation to the axis, and another convergent lens. The arrangement is such that two divergent elementary beams produced by the laser are brought together to have substantially less divergence.

Abstract: The cut-out device comprises a saturable absorbing medium and a monochromatic filter disposed between two amplifying media in the path of laser light pulses. The cut-out device forestalls amplification of light spontaneously emitting in one amplification medium by the following amplification medium, thereby reducing energy losses from pumped amplifying media prior to the passage of a laser pulse.

Abstract: A method of enamelling sheets (e.g. cooker panels) in which hooks are used to suspend the sheets during the enamelling procedure and in which deposits of enamel are prevented from building up on the hooks by covering them initially with an under-coat of non-pellicular aluminium paint. This has the effect of retaining the enamel that may be deposited on the hooks until after firing (thereby avoiding spoiling the enamel of the sheets with particles of broken hook enamel) but of enabling the enamel to be removed after firing either by heating and quenching the hooks or by vibrating them (or both).

Abstract: The invention relates to a method of preparing beta alkaline alumina parts particularly for use as solid electrolytes in electric cells of the sodium-sulphur type. It consists in mixing alumina and an alkaline carbonate in predetermined quantities, heating the mixture, crushing after cooling, forming the parts, sintering them and, after said forming, but prior to sintering depositing a layer of a compound of said alkaline metal on the surface of the parts in contact with the atmosphere to create an atmosphere rich in sodium in the immediate vicinity of the parts during sintering for compensating any loss of the element which may occur from the parts and minimizing the loss of alkaline metal by diffusion towards the outside of the parts.

Abstract: The invention concerns a travelling wave laser and has application to the reduction of the divergence of laser beams. The electrodes between which the travelling electric discharge for the excitation of the amplifier gas takes place have a cross-section in the shape of two polished rounded-off points facing each other, so as to prevent spurious reflections of light towards the discharge zone and to reduce the divergence of the output beam which is converged by means of a simple optical system.

Abstract: The invention relates to an electrolytic resistor comprising a water-repellent insulating tube through which there flows an alkaline solution containing a suspension of zinc. The positive end of the resistor has a metallic grid suitable for trapping the zinc particles, and the negative end has either an air electrode or a ring made of a metal having, more especially, high hydrogen supertension, this ring itself possibly having holes or projections suitable for promoting the progressive deposition of zinc dendrites. The invention is used in zinc-air storage cells.

Abstract: The invention relates to a laser generator device emitting at a wavelength of 1.3 microns. This device includes a laser oscillator with a neodymium-doped glass, an iodine gas amplifier disposed at the output of the oscillator and means for causing the emission of the oscillator to take place at a wavelength close to 1.3 microns. Application to the production of plasmas.

Abstract: The invention relates to a gas laser generator. This generator comprises two flat energization lines having the shape of arcs of a half parabola, these lines being in electrical continuity along a common segment connecting the merged focusses of the half parabola arcs and a joint situated near the apexes of the half parabola arcs. Application to nitrogen laser generators.

Abstract: The invention relates to a method and device for regenerating zinc from an alkaline zincate solution. To this end, the solution is contacted with two electrodes under tension, so that zinc is deposited on the negative electrode and oxygen is evolved at the positive electrode, the solution being conveyed at a sufficient speed for the zinc to be deposited and then detached from the electrode. In an alternative embodiment, during a first period, the solution is conveyed at a low or zero speed so that the zinc can be deposited, and is then conveyed at a higher speed so as to detach the zinc particles. The negative electrode is preferably made of magnesium and can be a cylindrical bar or inter alia can be formed with projections. The invention is applicable to electric vehicles.

Abstract: A battery containing an alkaline electrolyte, having within a container, said electrolyte and two electrodes separated by a separator; said separator being made of a partially reticulated polyvinyl acetal produced by the action of at least one aldehyde on polyvinyl alcohol; preferably an aromatic aldehyde, which may also have at least one hydroxyl radical, being used together with formaldehyde.

Abstract: The invention relates to a lithium electric cell comprising, in a first embodiment, a lithium negative electrode and a positive electrode made in particular of copper sulphide, the electrolyte comprising a salt such as tetralkylammonium having predominantly anionic conductivity and, in a second embodiment, said cell comprises between the electrodes a separation membrane made of an anionic exchanger material such as quaternized polyvinylpyridine, the electrolyte of the cathode compartment being tetralkylammonium chloride, the electrolyte of the anode compartment being a salt such as lithium perchlorate having predominantly cationic conductivity. The invention is implemented in cells in thin layers.

Abstract: Cells are fed in series with an alkaline solution containing zinc in suspension and electrically connected in series. The cells are grouped in modules fed in parallel with the solution and electrically connected in series, each module being fed with the solution through an inlet pipe and an outlet pipe. Electrolytic resistors are connected in the hydraulic circuit of each pipe to maintain a potential difference in the solution between the modules and a tank for storing the solution.

Abstract: The invention relates to an electric cell of the sodium-sulphur type particularly adapted for undergoing complete recharging. It comprises a cathode tank containing sulphur, an anode tank containing sodium, these reagents being separated by a solid electrolyte tube disposed in said cathode tank fitted with graphite felt washers ensuring cathode collection of the current generated, wherein said electrolyte tube is surrounded by a grating which is connectable to the negative terminal of the recharging current source by means of a resistor. The invention is used in cells for electric vehicles.

Abstract: Method for manufacturing alkaline beta alumina parts, consisting in heating a mixture of alumina and of sodium carbonate, in crushing the powder obtained, in shaping the parts, in sintering them at 1650.degree. C, those parts being arranged in a sintering enclosure suitable for creating, in the vicinity of the parts, an atmosphere which is rich in sodium. The invention is implemented in the embodiment of an electrolyte for sodium-sulphur cells.

Abstract: The alpha alumina part is heated to between 1400.degree. C and 1600.degree. C for 10 to 20 hours in a mass of alkaline carbonate or aluminate. It is then disposed in contact with a blank of the alkaline beta alumina part in a sintering enclosure suitable for establishing an atmosphere which is rich in alkaline metal and in heating this enclosure to between 1600.degree. C and 1700.degree. C for between 30 minutes and 4 hours, so as to sinter the alkaline beta alumina part while effecting the connection thereof to the alpha alumina part. The invention is used in manufacturing sodium-sulphur type electric cells.