Abstract: The present invention relates to a catalyst system based on fulvene cyclopentadienyl metal complexes, to a method of producing said catalyst system and to the use thereof for the polymerization and copolymerization of olefins and/or dienes.

Abstract: A method of producing metal fulvene insertion complexes, as well as new fulvene metal insertion complexes and the use thereof as catalysts for the polymerization of olefins and/or dienes and as hydrogenation catalysts.

Abstract: Method and arrangement for buffering between two synchronously pulsed devices which transmit and receive data packets of data words, the output being enabled as soon as the number of output clock cycles after the start of a data packet exceeds a start value which is determined in advance by measuring the output clock cycles as a function of the input clock cycles.

Abstract: The invention relates to an embroidery machine for embroidering embroidery fabric (23), particularly for chain stitching and drop stitching. The embroidery machine has an embroidery head (1), located above the embroidery fabric (23), and an embroidery needle (2) is movably supported in the embroidery head (1) in such a way that by means of drive mechanisms, the embroidery needle (2) is movable up and down and is also rotatable about its longitudinal axis. The embroidery machine also has a stitch plate (3), which is located below the embroidery fabric (23) and on which at least some of the embroidery fabric (23) rests during the embroidering. A thread layer (18) is located on the side of the stitch plate (3) remote from the embroidery fabric (23) and guides the embroidery thread (10) for stitching, and by rotation of the thread layer (18) the embroidery thread (10) can be laid around the embroidery needle (2) that has pierced the embroidery fabric (23).

Abstract: A pot spinning machine holds a yarn rewinding tube in ready position during the spinning operation for immediate movement to an operative rewinding position in the event of a yarn break so that the broken end of yarn is not lost by winding onto the yarn cake already formed in the spinning pot and the yarn cake may then be properly rewound. The yarn break is detected with the aid of a yarn sensor which then emits a signal for immediately moving the rewinding tube into the rewinding position and clamping the yarn end. The rewinding operation can begin, even in the absence of a loose end of the yarn, if the yarn has assumed the form of a chord-like yarn segment extending substantially in the circumferential direction against the inner face of the yarn cake deposited onto the inside wall of the pot, which can be grasped and utilized to initiate the rewinding operation.

Abstract: In the permeable structure, which is built up of sheets, continuous channels are arranged in rows and between the rows of channels are formed flow spaces which at opposite sides are bounded bit cover plates. In the flow spaces (4) at least two successive transverse bridges (6) are arranged on the same level, the transverse bridges (6) in at least half of the sheets having a different length (B) and the channels (1) extending essentially perpendicular to the flow spaces (4).

Abstract: In the process for producing a homogeneous and finely crystalline silicon nitride ceramic, ceramic powder is milled, mixed with shaping aids, the mixture is shaped into parts and the shaped parts are subsequently sintered in a nitrogen atmosphere. According to the invention, sintering is carried out in a multistage process at temperatures T.sub.max in the range from 1700.degree. to 1900.degree. C. using gas pressures in the range from 0.3 to 50 MPa. In a first temperature stage, a temperature from 0.9 to 0.96.multidot.T.sub.max is maintained over a time period from 10 to 50 minutes at an N.sub.2 pressure from 0.2 to 1.2 MPa, while in a second temperature stage a temperature from 0.97 to 0.985.multidot.T.sub.max is maintained over a time period from 20 to 80 minutes at an N.sub.2 pressure from 3 to 6 MPa. Then the temperature is increased to T.sub.max and the pressure is increased to from 7 to 50 MPa.

Abstract: In the heat exchanger module, produced by stacking sheet cards provided with openings and subsequently joining the individual cards of the card stack, each sheet card (2) or group of sheet cards of the stack is arranged rotated about a common axis by an angle .alpha. of between 0.degree. and 30.degree. with respect to the preceding sheet card (2) or group of sheet cards, the openings (3) forming helical channels (4).

Abstract: Silicon slip-casting composition, and process for the preparation thereofA silicon slip-casting composition comprising from 25 to 50% by weight of water and a pulverulent solid component which essentially comprises silicon and inorganic sintering aids is described, where the aqueous phase has a pH in the range from 8 to 9.5. The solid component comprises from 65 to 88% by weight of silicon, from 5 to 24% by weight of Y.sub.2 O.sub.3, from 2 to 9.6% by weight of Al.sub.2 O.sub.3 and from 1 to 5% by weight of SiO.sub.2 on the surface of the Si particles.The mean particle size of the solid component is at most 20 .mu.m, in particular at most 5 .mu.m. The invention also relates to a process for the preparation of the slip-casting composition.

Abstract: A projectile equipped with an infrared target seeking system at its bow and an arrangement for correcting the flight course of the projectile, with the target seeking system having at least one deflection device for scanning the target area. To obtain a rosette-shaped scanning pattern of the target area without the use of gyro stabilized mechanical systems, the projectile rotates about its longitudinal axis and the target seeking system includes a laser which is followed by a beam deflecting device which deflects the laser beam periodically and linearly within a fixed scanning plane passing through the longitudinal axis of the projectile. Preferably the laser beam is also amplitude modulated.

Abstract: A target detection method for a flying body provided with a search head, with the flying body rotating during its descending flight and scanning the area for possible targets, and in which the geometric dimensions of possible targets are determined in the scanning direction (Y direction) and in a direction perpendicular to the scanning direction (X direction) and are compared with corresponding stored values to determine the presence of a target. To avoid distortions of the scanned target in the Y direction, at least the angular velocity .omega. of the flying body, and preferably also the angle .phi. between the axis of rotation and the symmetry axis of the flying body, is continuously determined during the scanning process and, image correction values are calculated from the determined values and used to correct the geometric dimensions of the possible target in the Y direction.

Abstract: For producing a component of silicon-infiltrated silicon carbide, having a porous sliding surface, a component of silicon-infiltrated silicon carbide (composition: 40-95% by weight of SiC, 1-45% by weight of carbon particles of grain size 0.1 to 500 .mu.m and 1-25% by weight of silicon) is machined on parts of the surface, a sliding surface thus being produced. The resulting component is heated in an oxygen-containing atmosphere at temperatures from 700.degree. to 1410.degree. C. until the carbon particles present in the sliding surface have been at least partially oxidized with the formation of pores.

Abstract: A process for compacting a porous ceramic structural member having a compated shape and an optional size by encapsulation with material of the same type and capable of sintering and subsequently subjected to hot-isostatic pressing; immersing the preformed body in a suspension of a material of the same type in a solvent but which contains no sintering aid and forming a first encapsulating layer; evaporating the solvent; immersing the thus obtained body in a second suspension of a material in a solvent of the same type capable of sintering and which contains one or more sintering aids, and forming a second encapsulating layer; evaporating the solvent; subjecting the thus obtained body at an elevated temperature in an atmosphere of a protective gas for a sufficient period of time to sinter the same; isostatically compacting the body provided with a tight-sintered surface; and mechanically removing the encapsulating layers.

Abstract: A mixing chamber for thickening sludge, especially sludges in a sewage clarification plant by means of a flocculation agent in combination with an overflow drainage means wherein the sewage feed to the bottom of the mixing chamber enters a mixing zone and flows upwardly into an overflow at the top and out through a diversion means for the thickened sludge leading to a sedimentation belt or to a press filter, handling to the outside of the mixing chamber. The top of the mixing zone is widened by means of a flow section for the thickened sludge which is formed by dewatering through the perforated screen walls and the waste water is disposed downstream of the agitated mixing zone.