Abstract: Various vacuum ultraviolet monochromators embodying a rotatable diffraction grating and fixed entrance and exit slits, and working at a predetermined magnification are disclosed which provide improved optical performances by a correction of the odd terms of the wavefront aberration. In one group of instruments the fixed angle 2.theta. between the entrance and the exit beams is 90.degree. and the magnification 1. In another group, grazing incidence instruments are considered, 2.theta. being equal to 166.degree..

Abstract: A method of making plate material consisting of agglomerated clay-based particles, comprising providing a liquid particle suspension such as slip within a gap left between two continuously travelling confronting electrodes at a given voltage applied thereto, subjecting the suspension to an electrophoretic action between said electrodes and an adjacent counter-electrode subjected to a different voltage and controlling the formation and thickness of the electrophoretic deposits on said first electrodes so that when they leave the electrophoretic field they will be fused together with their outer surfaces having contacted each other and recovering said plate formed continuously from both layers of electrophoretic deposits.

Abstract: Two current supply conductors connected to an emissive filament located within a vacuum enclosure are each constituted by a leak-tight tube formed of material other than a heavy metal which traverses the enclosure wall through a leak-tight bushing, and by a conductor of electrically conductive heavy metal such as copper which is placed inside the leak-tight tube and completely isolated from the vacuum enclosure. This arrangement permits the continued use of heavy metals such as copper for current supply to ion sources without any attendant danger of heavy metal ion formation in the emitted beam.

Abstract: The measuring cell is composed of at least one cavity hollowed in a block of chemically inert material or material made chemically inert at least at the surface. The cavity defines a first cylindrical space whose bottom is, over a reduced part of its diameter, extended by a second space defining the measuring chamber proper, of conical, frustoconical or substantially hemispherical shape. The first cylindrical space is designed to receive a measuring electrode terminated by a magnetic torus and, applied, and if necessary held by means of a ferromagnetic ring, against the latter, a membrane, while inlet and outlet ducts for the liquids to be assayed are formed in the block. The cell is especially useful for micro-assays of biological fluids.

Abstract: Water soluble agents effective as immunological adjuvants for stimulating in the host the immune response to various antigens, comprising an acyl-muramic acid group, wherein acyl means acetyl or glycolyl, and a short peptide chain linked to said acyl-muramic acid group, the first and second amino acids of said peptide chain being preferentially alanine and glutamic acid respectively.

Abstract: New organo-lithium initiators, their synthesis, and their use. The initiators have the formula: ##STR1## in which R" is either a hydrogen atom or a methyl radical; either n is 1, in which case R' = H and m and p are integers, the sum of which is between 0 and 10 inclusive, or n is 2, R' then being an alkyl radical of 2 to 8 carbon atoms and m =p =0; and R is an alkyl radical of 1 to 4 carbon atoms.The initiators are prepared by reacting compounds of the formula: ##STR2## with an alkyl-lithium RLi in a non-polar solvent in the absence of any polar solvent or complexing agent.The initiators are used to prepare polydienes of high stereoregularity by reacting with a diene, and the polydiene is used to prepare a three-block or star copolymer by reacting with an anionically polymerizable monomer.

Abstract: A method for measuring the fatigue of a test-piece subjected to mechanical stress. The test-piece is stressed and pulses of ultrasonic waves are transmitted along the surface region of the stressed area and received. The acoustic attentuation of the waves, due to the fatigue caused by the stress, is measured and provides an indication of the amount of fatigue.

Abstract: This device comprises a generator of electric signals adapted to generate a first signal whose frequency is proportional to the speed of the output shaft of the transmission and whose amplitude is a function of the load of the motor with which this transmission is associated, and means for producing from said signal the ratio change characteristics.The device further comprises means for producing from the generator signal an additional electric signal whose amplitude is a function of the frequency of the first signal, means for weighting and comparing said first signal and said additional signal so as to obtain a signal representing periodically the desired state of the transmission, and means for memorizing the desired state of the transmission connected to the measuring and comparing means to change the transmission from one ratio to the next ratio as a function of the signal produced by the weighting and comparing means.

Abstract: The invention relates to a step by step motor and/or brake device through controlled translation, comprising two assemblies arranged substantially coaxially about the same shaft, one of them being slidable along said shaft, and the other assembly being rotatable about said shaft.The device according to the invention may be used in mechanical, pneumatic or electrical equipments, in automatic arrangements, in servo-controls, as modifiable drives, step by step motors, step by step brakes.

Abstract: The apparatus comprises a principal light source, condenser, lenses, object and image planes movable with respect to one another and an auxiliary light exposure source. The condenser is constituted by two thin stepped lenses between which is arranged a corrector screen for the variations in illumination in the image plane due to the inclination of the useful beam to the axis of the system. This screen operates perpendicularly to its surface, the constituent elements of the source, of the condenser and of the pupil of the lenses used being fixed with respect to one another and movable in a single unit relative to the document to be reproduced according to the focal length of said lens determining the size of the document. The apparatus is useful for the reproduction of transparent documents in black and white or in color.

Abstract: The easy direction of magnetization of an amorphous magnetic film is brought in the plane of the film by annealing this film in an oxygen-free atmosphere composed of a gas selected from the group comprising argon, neon, krypton and xenon at a temperature below the temperature of crystallization of the alloy which constitutes the film. The depth of penetration of the rare gas into the film is adjusted by modifying the parameters of annealing temperature and time in order to modify the easy direction of magnetization to a greater or lesser depth within the film.

Abstract: An egg white substitute is prepared by a process involving the acidification of milk serum at a pH of 2 to 6, heating between 45.degree. and 80.degree. C. for five to twenty minutes, then sudden cooling to a temperature comprised between 15.degree. C. and 25.degree. C. and subsequent alkalinization to a pH comprised between 7 and 9.

Abstract: The trawl-net apparatus includes, between the net and the bottom, a closing-opening mechanism provided with a first control device. The mechanism holds the entrance of the bottom closed while leaving the rear of the net open. Under action of its control device, the rear of the net is caused to communicate with the entrance of the bottom. A folding over closing system is provided with a second control device and under the action of this control devices allows the mouth fold back rearwardly, then ensures, by a stopper, the closing of the mouth. The trawl-net with controlled opening and closing is advantageously used for selective gathering of pelgic micro-necton.

Abstract: A psychrometer or pick-up for measuring the content of water in a gas flow comprises a first sensor or probe for measuring the dry temperature of the gas and is arranged directly in the flow of gas, a second sensor or probe for measuring the wet temperature of the gas and is surrounded by a sheath of a material capable of absorbing a volatile liquid, the second sensor or probe with its sheath also being arranged in the flow of gas, a pair of screens mounted on opposite sides of the second sensor and the sheath for protecting the sheath against thermal radiation, and a wetting device, preferably formed by a dosing pump connected to a nozzle, for injecting successive doses of a predetermined amount of the volatile liquid directly into the interior of the sheath and onto the screens to prevent excessive and insufficient moistening of the sheath and the screens.

Abstract: The invention provides an electrochemical gauge for measuring oxygen pressures having an internal reference and a solid electrolyte. The internal reference is provided by a mixture of lead and lead oxide forming a redox couple. The electrochemical gauge may be used to determine the ratio of the partial pressure of CO to that of CO.sub.2 in equilibrating combustion gases.

Abstract: A process and device for micro-analysis in which a thin layer of anticathode material is scanned by means of a pencil-beam of electrons. The X-rays formed are received by a thin layer of converter where they give rise to a current of photoelectrons which is subject to an intensity measurement by an analyser.From the measurement of intensity of the photoelectrons are deduced the properties of the zone of the anticathode which receives the pencil-beam.

Abstract: The invention relates to an injection internal combustion engine.The engine has a device for injecting fuel, preferably at high pressure, into the cylinder of cylinders, a device adjusting the injection advance in dependence on the load, and a controlled ignition device, the said engine being arranged to use a fuel other than a petroleum product, preferably an alcohol based product, and being characterized in that its dimensional characteristics are determined to supply a volumetric compression ratio between 12 and 20, preferably between 15 and 18 and in particular close to 16, and in that the device adjusting the injection advance is such that it supplies, at least for starting, a high value of advance, particularly of the order of 180.degree..

Abstract: The invention concerns the centering, the guiding and the correction of shape of liquid streams of different metals. A series of various and different electrical conductors A, B, C, D, even in number, are disposed along generatrices of a prism whose axis X coincides with the axis to be imposed on stream V. High frequency alternating currents opposite in direction are passed along two successive conductors. Application to different types of casting in particular.

Abstract: A method and apparatus for manufacturing articles made of paper, plastic and the like from n series of strips of such materials is provided wherein n represents the number of strips and is an integer equal to or greater than two. Initially transverse perforations are formed at regular intervals in each of the strips to define in each strip a plurality of elementary sections having the same length L. The strips are then superimposed such that each perforated strip is offset with respect to an adjacent strip in the longitudinal direction by a distance equal to L/n. Thereafter the apparatus which performs the method exerts, successively and independently, on each of the successively superimposed strips a pulling and tearing off action to define the longitudinally offset superimposed perforated strips into separate elementary sections.

Abstract: The invention concerns a process and a device for roasting an agro-food product in the form of grains.The process consists of fluidizing an auxiliary body in the form of fine solid particles in an enclosure 1, and putting the grains of the product to be roasted in flotation in the fluidized bed of particles of which the temperature is adapted to roasting, to generate the roasting by the effect of the shocks of the fine particles of the auxiliary body with the grains of the product.The invention can be applied particularly for the roasting of grains of a product such as coffee, cocoa, etc.