Abstract: In a method and device for filtering a suspension of particles in a liquid the liquid is passed continuously through a porous membrane, particles from the suspenion gradually accumulating on the membrane and clogging its pores. The filtered liquid is caused to flow momentarily in the reverse direction to return the accumulated particles to the suspension and so unclog the membrane. To achieve this the filtered liquid is fed into one end of a conduit wound around an axis and recovered from its other end, and the conduit is rotated about its axis, the speed of rotation gradually increasing, and then suddenly stopped.

Abstract: The generator comprises an optical cavity (3, 4) resonating according to an axis (2) and two annular electrodes (5, 6) disposed along said axis, one of said electrodes (5) being provided with gas injection channels (9, 10) having injection axes (11, 12) directed toward the other electrode (6) and inclined at an angle of 45.degree. with respect to the axis (2) of the resonator, the number and the cross-section of said channels (9, 10 . . . ) being selected to enable the laser gas to be injected at supersonic speed. The operating method consists in maintaining a laser gas pressure upstream from the injection channels (9, 10) which is at least 50% greater than the downstream pressure.

Abstract: Arsine or phosphine are thermally decomposed to form a molecular beam of arsenic or phosphorous by using the inside surfaces of a thermal decomposition duct (11) made of quartz or of boron nitride and heated on the outside by radiation from a filament (30). Pierced internal partitions (6a, 6b, 6c, 6d) having successive circumferentially offset holes (6p, 6q, 6r, 6s) increase the decomposition surface area and prevent a molecule from passing through the duct along a straight line.

Abstract: The method consists in clamping the edges of the tape between two jaws of a clamp and in displacing the clamp vertically upwardly. The apparatus includes two vertical columns (10, 11) along which two carriages (12, 13) are capable of moving, with each carriage having a corresponding clamp (14, 15) and means (16, 17, 19, 20) for controlling clamp operation and vertical displacement of the carriages along the columns. Such semiconductor-coated material is suitable for making solar photocells, for example.

Abstract: High sensitivity interferential electro-optical modulator. The invention concerns an interferential electro-optical modulator. This modulator contains a Mach-Zehnder integrated interferometer in which each interferometer arm (24, 26) is overlapped by an electrode (40, 42), itself surrounded by two lateral electrodes (44, 46, 48, 50) to uniformize the electrical field crossing through each arm perpendicular to the face of the electro-optical crystall on which it is formed. Application to the detection of accoustic waves and low voltage measurement.

Abstract: The window handler circuit is inserted between an image memory (7) having as many pages as there are possible windows and a screen controller capable of reading from any of the pages of the image memory. The handler comprises two auxiliary memories (3, 4) each of which stores bit maps in which a logic one bit indicates that the corresponding window includes an image element in the same line or the same column as the case may be as the screen position currently being scanned. A battery (5) of AND gates receives the line and column bit maps associated with the current screen position and generates a third bit map in which each logic one bit indicates that the corresponding window includes an image element at the current screen position. A priority encoder (6) then selects the visible or "uppermost" window from the said third bit map by generating the number (N) of the page to be read in the image memory (7).

Abstract: A device for abstracting the liquid phase from a suspension comprises a microporous membrane (23) applied on the outside of a microporous body (22) to which a flat capillary duct (11, 18) is fixed. Means (9) are provided to rotate the duct about a vertical axis, with the membrane being immersed in the suspension in such a manner as to provide tangential filtering of the suspension and to cause the liquid phase filling the duct after passing through the membrane and the porous body to be ejected centrifugally and received by a receptacle (5) provided for the purpose.

Abstract: It comprises a receptacle containing a bath of molten silicon, the bottom of the receptacle includes a slot (7) through which there passes a tape (9) which is drawn vertically through the bath. The vertical wall of the slot (7) is downwardly flared, the horizontal section of the slot (7) includes a rectangular area (25) whose length is equal to the width of the tape (9) and two circular areas (28, 29) disposed at the two ends of the rectangular area (25), the diameter (32) of the circular areas (28, 29) being greater than the width of the rectangular area (25).Application to making solar photocells from silicon.

Abstract: Optical system having application to robotics for determining an object's position. The present system consisting of a laser generator 1 with, devices 11 modulating the wavelength of laser generator frequency along an ascending ramp. An optical system 8 for concentrating radiation near the object, receiver 16 picks up a luminous signal transmitted by the object 10 and reflected on to an optical lamp 6. A processing circuit 17 measures the time in which elapses between the beginning of the shift in wavelength and the moment when the luminous signal is picked up by the receiver.

Abstract: A crucible containing molten silicon, has a strip of carbon film vertically transported through the melt, an optical system imaging a small area of the silicon surface onto a photodetector, said image area being that of the silicon liquid-solid interface, and a servo system connected to said photodetector and to an electrical drive for feeding silicon into said melt. The invention is applicable to the manufacture of solar cells.

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: A method of producing a solid electrolyte for an electrochemical cell, the cell comprising at least one first complexing polymer presenting in its monomer pattern at least one heteroatom and at least one ionizable alkaline salt complexed in the said polymer, wherein said complexing polymer is mixed with at least one second polymer miscible with the said complexing polymer and having cross-linkable functions; said cross-linkable functions then being physically cross-linked, with the complexing polymer being brought to an essentially amorphous state during said cross-linking operation.The electrolyte obtained can be used in electrochemical cells operating at ambient temperature.

Abstract: The laser comprises a gas-filled channel (51) extending between a pair of metal plates (2 and 3). The laser is excited by a spark discharge through the gas from one plate to the other. The energy for the spark comes form a pair of built-in capacitors extending between the plates on either side of the channel. The plates constitute the plates of the capacitors, and apart from a plastic retaining wall (37, 39) round each capacitor, the capacitor dielectric is water. The water is advantageously pumped (47) round a cooling circuit (48), and it is not permanently damaged if an accidental discharge takes place through the water. The invention is particularly applicable to nitrogen and to excimer lasers.

Abstract: The active material is constituted by an alkali metal in the zero valent state which alkali metal is inserted into an insertion compound. The insertion compound receiving the alkali metal has an ordered three-dimensional lattice structure and is constituted by at least one intermetallic compound having polyatomic anionic clusters with atoms chosen from the group constituted by gallium, boron and aluminum, and with structuring counter ions chosen from the group constituted by alkaline earth and alkali ions.

Abstract: A gas laser in which the gas is excited by laser discharge, said laser including two capacitors formed by two parallel metal plates (2, 3) between which two dielectric parts (4,5) are spaced apart to form a passage (6) which contains the laser gas. It further includes a transformer (13) whose secondary winding (12) is connected to the plates and whose primary winding (14) is connected in series with a capacitor (15), means (17) for charging and capacitor and a thyristor (16) for discharging the capacitor in the primary winding. Application to exciting gas lasers in which the gas contains a dye stuff.

Abstract: In a method for determining the physical characteristics of a silicon wafer, one side of the wafer (4) is removably fixed to the base (2) of a container (1) so as to close off a hole (3) therein. An electrical connection to this side of the wafer (4) is made thru the hole (3). The wafer (4) forms the working electrolyte of a cell comprising an electrolyte contained in the container (1). An auxiliary electrode (14) is removably placed in the electrolyte. The method and the device implementing it can be used to determine the crystallographic and electrical characteristics of a sample of silicon.

Abstract: First and second identical filters (6, 20) are connected in series. A backpressure unit (30) for intermittent backwashing is connected to the outlet from the second filter. Means are provided for measuring or setting the pressure P.sub.1 at the inlet to the first filter, the backpressure P.sub.2, the pressure P.sub.3 of the liquid between the two filters and the pressure P.sub.4 at the outlet from the second filter. Means (34) determine A=P.sub.1 -2P.sub.3 +P.sub.4, and B=(K/2N)(P.sub.2 -2P.sub.1 +P.sub.4), where K and N are constant coefficients, and a circuit (35) causes the backpressure unit to apply backpressure for backwashing when A=B. This amounts to comparing conditions in the first and second filters and triggering backwashing only when required, thereby avoiding wasting time with too frequent backwash operations, or conversely with dismantling and regenerating the filters due to too infrequent backwashing leading to clogging that cannot be cleaned by backwashing.

Abstract: A plurality of electrodes (7, 10) are arranged along two rows facing each other in pairs, leaving a spark gap in between the rows of electrodes. Each row comprises a plurality of electrodes connected in parallel. The electrodes are in a gas. The problem is to trigger simultaneous arcs between each pair of electrodes. This is achieved by extending an insulated conductor (15) parallel to the rows and then in applying pulses to the insulated conductor to obtain a corona discharge around it. The resulting ions suddenly reduce the striking potential across the spark gap. A potential difference is applied across the gap by a generator (12). The potential is below the nonionized striking potential and above the ionized striking potential. The sudden drop in striking potential ensures that all pairs of electrodes strike substantially simultaneously. The apparatus can be used to excite a high repetition rate gas laser generators.

Abstract: A fabrication method for use in making photocells consisting in depositing on the top face of a carbon ribbon (4) being moved horizontally in its lengthwise direction through an oven (9) a layer of silicon, said oven being imparted a vertical temperature gradient, and in burning away the portion of the ribbon supporting the silicon layer immediately following deposition of said layer.

Abstract: An electrochemical cell which has a negative electrode (1) including an alkali or alkali-earth metal dissolved in liquid ammonia, a positive electrode (2), an electrolyte (3), and a separator (4). The positive electrode (2) is constituted by a solution in ammonia of a chalcogen or of a chalcogenide or of an emulsion or suspension in ammonia of a solid compound suitable for intercalating the metal of the negative electrode (1). Said electrolyte (3) includes a solution of an iodide of an alkali or alkali-earth metal.The invention is used in the field of reversible high-power electric cells operating at low temperatures.