Abstract: A process for producing small particles of aluminum nitride suitable for sintering and the particles thus-produced. The process comprises reacting particles of gamma alumina, or a precursor thereof, of less than 1 micron in size with a stoichiometrical excess of finely divided carbon in the presence of nitrogen, or a precursor which provides nitrogen in the reaction conditions, first at a temperature in the range of 1550.degree. to 1700.degree. C. for a period of between 1 and 6 (preferably 1 to 4) hours and then at a temperature in the range of 1750.degree. to 1850.degree. C. for a period of 1 to 4 (preferably 1 to 2) hours, followed by cooling said reaction mixture and reheating to a temperature in the range of 500.degree. to 700.degree. C. in an oxygen-containing atmosphere, and maintaining the temperature until excess unreacted carbon is removed.

Abstract: A polymerization method carried out in the presence of unsaturated hydroperoxides useful as molecular weight regulators, is disclosed. Also disclosed are polymers and oligomers made by this process and articles of manufacture comprising one or more polymers or oligomers made by this process. These molecular weight regulating hydroperoxides provide the ability to introduce an epoxy functionality to the oligomer or polymer as well as an additional functionality and a primary hydroxy group. Further, omega substituted or alpha, omega disubstituted polymers may be synthesized using the unsaturated hydroperoxides of the present invention.

Abstract: The manufacture of a refractory composite material protected against corrosion and comprising fibrous reinforcement densified by a matrix, comprises a step of forming, either within the matrix or at its surface, at least one continuous layer constituted by a ternary silicon-boron-carbon system obtained by chemical vapor deposition or infiltration. The elements silicon and boron are thereby distributed uniformly, with the boron content in the Si-B-C system being not less than 5% in atom percentage.

Abstract: Dye-donor element for use according to thermal dye transfer methods comprising a support having thereon a dye/binder layer comprising a dye carried by a polymeric binder resin, said dye corresponding to the following general formula ##STR1## wherein R represents a hydrogen atom, a C.sub.1 -C.sub.8 alkyl group, a C.sub.1 -C.sub.8 alkoxy group, a C.sub.3 -C.sub.8 alkoxyalkyl group or a halogen atom;R.sup.1 and R.sup.2 (same or different) represent a C.sub.1 -C.sub.8 alkyl group, a substituted C.sub.1 -C.sub.8 alkyl group, a cycloalkyl group, a substituted cycloalkyl group, an aryl group, a substituted aryl group, or R.sup.1 and R.sup.2 together represent the atoms necessary for completing a heterocyclic nucleus or substituted heterocyclic nucleus, or R.sup.1 and/or R.sup.2 together with Y represent the atoms necessary for completing a fused-on heterocyclic nucleus or substituted fused-on heterocyclic nucleus;Y represents a hydrogen atom, a methyl group, a halogen atom, a C.sub.1 -C.sub.

Abstract: A Roots-type machine is connected to an enclosure to be evacuated via a suction inlet portion, and to a primary pump via a delivery outlet portion. A bellows is disposed transversely in the inlet portion, one end of the bellows being fixed in gastight manner in the wall, and the other end being closed and movable, so that the bellows forms a regulating member for regulating the gas-flow sectional area in the inlet portion. The outside face of the movable end of the bellows is subjected to the pressure in the inlet portion, and the inside face of the movable end is subjected to the pressure in the delivery outlet portion via a rod passing through the wall, and via a channel. The invention applies to Roots-type machines, in particular for automatically regulating the pumping speed so as to match it to the flow-rate of the corresponding primary pump.

Abstract: Deep-frozen cooked potatoes are prepared by cooking potatoes, slowly cooling the cooked potatoes and then deep-freezing the cooled potatoes to a storage temperature in two steps so that in the first step, the cores of the potatoes are kept at the crystallization state of water for at least 15 minutes and so that in the second step, deep-freezing is continued until the frozen storage temperature is reached.

Abstract: A machine for creating a batch of blanks out of a pile of blanks and for removing the batch of blanks from the pile consists of a fixed stop positioned along one surface of the blanks, a jogging device disposed opposite the fixed stop, a movable stop positioned in a line with the fixed stop, a separating device arranged adjacent the fixed stop for engaging an upper surface of the pile to raise the pile to create a free space, a conveyor insert movable from a position outside of the pile into the free space for transferring the blanks raised by the separator out of the pile as a batch of blanks.

Abstract: A ski comprises a longitudinally extending body having a central region interposed between anterior and posterior segments. The body has a lower sliding surface whose width is defined by a pair of opposed lower edges connected to two lateral side surfaces that are inclined relative to the lower sliding surface. An upper surface is connected to the laterally side surfaces and has a width defined by opposed lateral edges which diverge towards the front of the ski in the interior segment of the body, and which are substantially parallel to each other in the posterior segment.

Abstract: The invention relates to catalytic compositions for the hydrogenation of chlorofluoroalkenes to fluoroalkenes, comprising a porous carrier impregnated with a metal of group VIII of the Periodic Table of the elements and with one or more compounds chosen from the salts of an alkali metal or alkaline-earth metal.The invention also relates to a process for obtaining these catalytic compositions and a process of hydrogenation by means of these catalytic compositions.

Abstract: A method for molding a fusible core from a molten metal, including filling a mold by forcing back molten metal under pressure into the mold by means of a positive displacement pump equipped with a pressure regulator and having an output rate, total filling of the mold corresponding to a manometric height; measuring the pressure of the forced-back metal; adapting the output rate of the positive displacement pump so that the growing pressure imposed on the forced-back molten metal does not undergo any sudden variation during filling of the mold; and limiting the pressure exerted on the molten metal to a maximum pressure value which is slightly higher than the manometric height.

Abstract: A food is cooked by placing the food on a support grill positioned inside a chamber, introducing steam and air into the chamber to provide hot moist air, directing the hot moist air in a vertically descending flow towards and through the support grill so that the food is contacted and cooked by the hot moist air, and cooling the chamber floor to prevent equilibration between the temperature of the floor and the temperature inside the chamber.

Abstract: A lidar with a laser transmitter for transmitting a laser beam and a receiver having receiving optics for detecting radiation reflected back from the beam by aerosol particles in the atmosphere, the receiver having an optical axis aligned with the beam. The receiver includes a number of radiation receiving elements such as concentric radiation detector elements placed in the receiving optics focal plane so that these concentric detector elements can measure backscatter radiation from the beam at several fields of view simultaneously. Backscattered signals at fields of view larger than the laser beams's divergence are due to multiple scattering. The unknown backscatter coefficient can then be eliminated by ratioing the lidar returns at the different fields of view.

Abstract: The field of the disclosure is that of enlarging optical lenses and, more precisely, binocular optical systems designed to be inserted into the night-time channel of an observation system, between a light intensifier tube and an observer's eyes. The disclosure can be applied especially to observation instruments for armored vehicles and, notably, periscopes for tanks. The disclosed optical system for a binocular device is of the type constituted by two groups, a forward group and a rear group, the rear group being constituted by a bonded doublet with plane rear face comprising a convergent convex lens bonded to a divergent lens, the lenses of the bonded doublet having different and complementary dispersions to compensate for the chromatism, and the focal length of the doublet ranging from 0.85F to 1.05F, where F is the focal length of the binocular device.

Abstract: The reel comprises a core and two identical end plates fitted in and assembled on the core. It is characterized in that each one-piece end plate (2) has a cylindrical support (6) on its inside face, which support fits into the core (1), and a reserve housing (20) in its outside face, which housing communicates with the periphery of the core, and in that the core has an inside bevelled surface (5) of limited angle (b) on each of its ends Application: packaging optical fibers or electrical conductors.

Abstract: The invention relates to heat resistant vermicular or spheroidal graphite cast iron. To make cast iron resistant to temperatures of 900.degree. C. to more than 1000.degree. C. while reducing manufacturing costs, the cast iron includes 4.7% to 7.1% by weight of Si equivalent, where Si.sub.eq is defined as Si+0.8Al, and in which the concentration by weight of Si lies in the range 3.9% to 5.3% and the concentration of Al lies in the range 0.5% to 2.5%.

Abstract: A reinforcing strip, and method of making same specifically adapted for use in reinforcing plies in the belt of rubber tires. The strip comprises a number, preferably 4 to 7, of parallel wires, tightly bound together by a wrapping wire or a binder. This strip form allows to combine the advantages of steel strip, i.e. high lateral and low radial stiffness and thinner plies, with those of conventional steel cord, i.e. high tensile strength and fatigue resistance.

Abstract: Dye-donor element for use according to thermal dye sublimation transfer comprising a support having on one side a dye layer and on the other side a heat-resistant layer, characterized in that said heat-resistant layer comprises a polycarbonate derived from a bis-(hydroxyphenyl)-cycloalkane (diphenol) corresponding to formula (I) ##STR1## wherein: R.sup.1 and R.sup.2 (same or different) represent hydrogen, halogen, a C.sub.1 -C.sub.8 alkyl group, a C.sub.5 -C.sub.6 cycloalkyl group, a C.sub.6 -C.sub.10 aryl group or a C.sub.7 -C.sub.12 aralkyl group;X represents the necessary atoms to close a 5- to 8-membered cycloaliphatic ring which is substituted with one or more C.sub.1 -C.sub.6 alkyl groups or 5- or 6-membered cycloalkyl groups or carries fused-on 5- or 6-membered cycloalkyl groups.

Abstract: A composite material comprising a substrate which is not or very slightly excitable by microwaves and a coating on at least a portion of said substrate based on polymeric composition containing at least 50% by weight of a polymer excitable by microwaves, wherein the melting point of the substrate is lower than the film-formation temperature of the polymeric composition and the process of making such composite.

Abstract: The rotary machine includes an automatically-retracting axial abutment system mounted between the rotary shaft of the machine and its case, the abutment system having a displaceable abutment portion that is prevented from rotating, a rotary abutment portion mounted on the displaceable abutment portion by means of a bearing suitable for transmitting axial forces to the displaceable abutment portion, a very stiff flexible device connecting the displaceable abutment portion to the case in such a manner as to enable the displaceable abutment portion to move through a small amplitude in translation along the axis of the rotary shaft, and an axial thrust transmission member for transmitting thrust from the rotary shaft to the rotary abutment portion, the thrust transmission member being shaped to be in contact between the rotary shaft and the displaceable abutment portion when the machine is at rest, and to drive the rotary abutment portion via purely static friction when the machine is rotating and is exerting axi