Abstract: A device for producing a dyed plastic melt and an undyed plastic melt includes a multi-shaft screw extruder, a first metering installation, a second metering installation, and a control installation for selecting between a first operating mode for producing the dyed plastic melt and a second operating mode for producing the undyed plastic melt. The first metering installation serves for feeding an undyed plastic material through a first infeed opening into a housing of the multi-shaft screw extruder, and the second metering installation serves for feeding at least one color granulate through a second infeed opening into the housing. The plastic material is fed exclusively by way of the first infeed opening such that residual color granulate or dyeing agent contained therein, respectively, which is still located in the second metering installation or in the region of the second infeed opening does not contaminate the undyed plastic melt.

Abstract: A device for producing dyed plastic granulate and undyed plastic granulate includes a multi-shaft screw extruder and an underwater pelletizing installation. A granulate changeover unit which separates the dyed plastic granulate from the undyed plastic granulate is disposed in a conveying direction downstream of the underwater pelletizing installation. The dyed plastic granulate is separated from the pelletizing water via a first separator installation, and the undyed plastic granulate is separated from the pelletizing water via a second separator installation. The separator installations are disposed so as to be mutually parallel. The device enables a simple, flexible and economical selective production of the dyed plastic granulate and the undyed plastic granulate.

Abstract: A screw machine includes an inductive heating device for the processing of material to be processed. The inductive heating device is used to heat the material in a heating zone. In the heating zone, at least one housing portion is made of an electromagnetically transparent material at least partly, the material being non-magnetic and electrically non-conductive, whereas at least one treatment element shaft is made of an electrically conductive material at least partly. During the processing of the material, the inductive heating device generates an alternating magnetic field that produces eddy current losses in the at least one treatment element shaft, the eddy current losses leading to a temperature increase of the at least one treatment element shaft. The material is heated on the at least one heated treatment element shaft, in particular until it melts.

Abstract: In a method for producing a mixture of a metallic matrix material and an additive, a metallic bulk material is molten in a multi-shaft screw machine in a heating zone thereof by means of an inductive heating device to form a metal matrix material. As the at least one housing portion of the housing of the multi-shaft screw machine is made of a non-magnetic and electrically non-conductive material at least partly in the heating zone, a high and efficient energy input for melting the metallic bulk material is achievable in a simple manner. The additive for producing the mixture is admixed to the metallic matrix material by means of treatment element shafts of the multi-shaft screw machine.

Abstract: A device for producing a dyed plastic melt and an undyed plastic melt includes a multi-shaft screw extruder, a first metering installation, a second metering installation, and a control installation for selecting between a first operating mode for producing the dyed plastic melt and a second operating mode for producing the undyed plastic melt. The first metering installation serves for feeding an undyed plastic material through a first infeed opening into a housing of the multi-shaft screw extruder, and the second metering installation serves for feeding at least one dyeing agent through a second infeed opening into the housing. In order for the undyed plastic melt to be produced, the plastic material is fed exclusively via the first infeed opening such that residual dyeing agent which is still located in the second metering installation or in the region of the second infeed opening does not contaminate the undyed plastic melt.

Abstract: A device for producing dyed plastic granulate and undyed plastic granulate includes a multi-shaft screw extruder and an underwater pelletizing installation. A granulate changeover unit which separates the dyed plastic granulate from the undyed plastic granulate is disposed in a conveying direction downstream of the underwater pelletizing installation. The dyed plastic granulate is separated from the pelletizing water via a first separator installation, and the undyed plastic granulate is separated from the pelletizing water via a second separator installation. The separator installations are disposed so as to be mutually parallel. The device enables a simple, flexible and economical selective production of the dyed plastic granulate and the undyed plastic granulate.

Abstract: A device for producing a dyed plastic melt and an undyed plastic melt includes a multi-shaft screw extruder, a first metering installation, a second metering installation, and a control installation for selecting between a first operating mode for producing the dyed plastic melt and a second operating mode for producing the undyed plastic melt. The first metering installation serves for feeding an undyed plastic material through a first infeed opening into a housing of the multi-shaft screw extruder, and the second metering installation serves for feeding at least one color granulate through a second infeed opening into the housing. The plastic material is fed exclusively by way of the first infeed opening such that residual color granulate or dyeing agent contained therein, respectively, which is still located in the second metering installation or in the region of the second infeed opening does not contaminate the undyed plastic melt.

Abstract: In a method for producing a mixture of a metallic matrix material and an additive, a metallic bulk material is molten in a multi-shaft screw machine in a heating zone thereof by means of an inductive heating device to form a metal matrix material. As the at least one housing portion of the housing of the multi-shaft screw machine is made of a non-magnetic and electrically non-conductive material at least partly in the heating zone, a high and efficient energy input for melting the metallic bulk material is achievable in a simple manner. The additive for producing the mixture is admixed to the metallic matrix material by means of treatment element shafts of the multi-shaft screw machine.

Abstract: A screw machine includes an inductive heating device for the processing of material to be processed. The inductive heating device is used to heat the material in a heating zone. In the heating zone, at least one housing portion is made of an electromagnetically transparent material at least partly, the material being non-magnetic and electrically non-conductive, whereas at least one treatment element shaft is made of an electrically conductive material at least partly. During the processing of the material, the inductive heating device generates an alternating magnetic field that produces eddy current losses in the at least one treatment element shaft, the eddy current losses leading to a temperature increase of the at least one treatment element shaft. The material is heated on the at least one heated treatment element shaft, in particular until it melts.

Abstract: A processing installation for devolatilization of polymer melts comprises a first extruder and a second extruder arranged downstream thereof in a direction of conveyance. The first extruder comprises several rotatably drivable first shafts which are provided with first treatment members and several devolatilization zones with associated devolatilization ports. Correspondingly, the second extruder comprises several rotatably drivable second shafts which are provided with second treatment members and several second devolatilization zones with associated devolatilization ports. The first treatment members have an external diameter which is smaller than or equal to that of the second treatment members. A devolatilization unit is arranged in a transfer zone which interconnects the extruders. The devolatilization unit comprises a perforated plate and a clearance arranged downstream in the direction of conveyance.

Abstract: A processing installation for devolatilization of polymer melts comprises a first extruder and a second extruder arranged downstream thereof in a direction of conveyance. The first extruder comprises several rotatably drivable first shafts which are provided with first treatment members and several devolatilization zones with associated devolatilization ports. Correspondingly, the second extruder comprises several rotatably drivable second shafts which are provided with second treatment members and several second devolatilization zones with associated devolatilization ports. The first treatment members have an external diameter which is smaller than or equal to that of the second treatment members. A devolatilization unit is arranged in a transfer zone which interconnects the extruders. The devolatilization unit comprises a perforated plate and a clearance arranged downstream in the direction of conveyance.

Abstract: An optically-enrichedpiperidine-2-carboxanlidecompound, in which the piperidine is optionally N-alkylated, is racemized by heating the compound in an aqueous medium, provided that the medium includes an organic co-solvent if the compound is N-alkylated. This process is particularly valuable, in conjunction with a resolution process, for the manufacture of levobupivacaine.

Abstract: An optically-enriched piperidine-2-carboxanlidecompound, in which the piperidine is optionally N-alkylated, is racemised by heating the compound in an aqueous medium, provided that the medium includes an organic co-solvent if the compound is N-alkylated. This process is particularly valuable, in conjunction with a resolution process, for the manufacture of levobupivacaine.

Abstract: A process for the preparation of optically-enriched pipecolic acid as a salt with an optically-active acid, comprises asymmetric transformation of pipecolic acid, as a racemic mixture of a mixture enriched in the opposite enantiomer from that desired, with the optically-active acid in a solvent comprising an acid that causes racemisation, in the absence of aldehyde.

Abstract: The subject invention concerns a process for preparing a compound of formula (3) ##STR1## in enantio-enriched form, comprising reducing a compound of formula (4) ##STR2## using an asymmetric enantiospecific reductant, wherein A.sup.1 .dbd.A.sup.2 .dbd.H or A.sup.1, A.sup.2 .dbd.O; B.sup.1 .dbd.B.sup.2 .dbd.H or B.sup.1, B.sup.2 .dbd.O; Z.dbd.H, C.sub.1-20 alkyl or a precursor thereof, or a removable protecting group for nitrogen, e.g, acyl or alkyloxycarbonyl; Y.dbd.H or a substituent; R.sup.1 .dbd.C.sub.1-20 alkyl; and R is an optional, additional substituent.

Abstract: The subject invention pertains to a process for the resolution of etodolac comprising the use of the resolving agent glucamine or a N-(C.sub.1-4 alkyl)-glucamine. The subject invention also concerns a process for converting a single enantiomer of etodolac into the racemate. The method comprises forming all ester of the carboxylate function of the enantiomer and treating with an acid or base.

Abstract: A process for the racemisation of an optically-enriched piperidine-2-carboxanilide compound, comprises heating the compound in the presence of an alkanoic or arylalkanoic acid. A process for the asymmetric transformation of such a compound comprises heating the compound in the presence of an acid as defined above, a chiral acid resolving agent and an inert cosolvent.

Abstract: A fuel circuit is disclosed for air-compressing injection-type internal combustion engines. The fuel circuit is provided with thermostat-controlled fuel preheating and has a switch-over valve controlled as a function of fuel temperature and a heat exchanger as a combined structural unit. The heat exchanger, through which only fuel flows, protrudes into the cooling water flow of the cooling water duct extending in the cylinder head.

Abstract: An arrangement of a soot filter in the exhaust gas system of an internal combustion engine equipped with an exhaust gas turbocharger whose turbine housing is arranged downstream of the exhaust gas manifold. For purposes of achieving a fastening of the soot filter at the internal combustion engine which is favorable from an assembly point of view, space-saving and compensating changes in length, the soot filter and the exhaust gas turbocharger form a unit which is retained, on the one hand, angularly movably at the exhaust gas manifold by means of a pipe connection of the soot filter and, on the other, at the crankcase by way of supports arranged at the exhaust gas turbocharger on the housing side.

Abstract: A connecting line between a compressor of an exhaust gas turbocharger flangedly connected at the exhaust gas manifold of an internal combustion engine and a suction pipe which consists of a first line part secured at the suction pipe and of a second line part which is coupled with the exhaust gas turbocharger by way of plug-in coupling sections and with the first line part by way of a line bridge fixed at the engine and provided with plug-in coupling sections. The line bridge encloses a mixing space between its coupling sections, in which exhaust gases controlled by an exhaust gas valve are fed to the through-flowing charging air.