Abstract: A process for preparing methionine includes the alkaline hydrolysis of 5-(2-methylmercaptoethyl)-hydantoin (methionine hydantoin) in an aqueous process solution containing alkali metal hydroxide and/or alkali metal carbonate and/or alkali metal hydrogencarbonate. The alkali metal cations in the process solution are potassium and sodium having a K/Na molar ratio range from 99/1 to 20/80.

Abstract: A side-channel blower for an internal combustion engine includes a flow housing, an impeller which rotates in the flow housing, a drive unit which drives the impeller, a housing wall with a radially delimiting housing wall, impeller blades arranged in a radially outer region of the impeller, a radial gap arranged between the impeller and the housing wall, an inlet, an outlet, and two flow channels. The housing wall radially surrounds the impeller. The impeller blades open in a radially outward direction. The two flow channels connect the inlet to the outlet and are fluidically connected to one another via intermediate spaces between the impeller blades. An interruption zone is arranged between the outlet and the inlet which interrupts the two flow channels in a peripheral direction. A radial interrupting gap is arranged between the impeller and the radially delimiting housing wall in the entire interruption zone.

Abstract: A process for preparing methionine includes the alkaline hydrolysis of 5-(2-methylmercaptoethyl)-hydantoin (methionine hydantoin) in an aqueous process solution containing alkali metal hydroxide and/or alkali metal carbonate and/or alkali metal hydrogencarbonate. The alkali metal cations in the process solution are potassium and sodium having a K/Na molar ratio range from 99/1 to 20/80.

Abstract: A side-channel blower for an internal combustion engine includes a flow housing, an impeller which rotates in the flow housing, a housing wall which surrounds the impeller, a drive unit which drives the impeller, impeller blades arranged in a radially outer region of the impeller, a radial gap arranged between the impeller and the housing wall, an inlet, an outlet, two flow channels which connect the inlet to the outlet, and an interruption zone arranged between the outlet and the inlet which interrupts the two flow channels in a peripheral direction. The impeller blades open in a radially outward direction. A respective one of the two flow channels is respectively formed axially opposite to the impeller blades in the flow housing. The impeller blades each comprise a V-shaped cross-section.

Abstract: This disclosure relates to a process for preparing D,L-methionine by feeding carbon dioxide to an aqueous potassium methioninate solution obtained by hydrolysis of 5-(2-methylmercaptoethyl)hydantoin, in order to precipitate out crude methionine, which is separated off and purified. In this process an aqueous solution of the separated-off crude methionine is purified by recrystallization from a solution containing potassium ions and also a crystallization additive. The crystallization additive is a nonionic or anionic surfactant, or a mixture of different nonionic or anionic surfactants. The recrystallization occurs by introducing a 60 to 110° C.-hot methionine solution into a 35 to 80° C.-warm methionine suspension, a temperature of which is lower than that of the introduced solution, such that the temperature of the methionine suspension being maintained between 35 and 80° C. during the addition. The crystallization additive is a sorbitan fatty acid ester or a mixture of different sorbitan fatty acid esters.

Abstract: A side channel blower includes a housing comprising a substantially tangential outlet. A housing cover comprises an axial inlet. At least one conveying duct is configured so that the axial inlet fluidly communicates with the outlet. An impeller is driven by a drive unit. The impeller is rotatably supported in the housing and comprises conveying blades which cooperate with the at least one conveying duct. An interruption region is arranged between the outlet and the axial inlet. The interruption region comprises a radially limiting wall and interrupts the at least one conveying duct in a circumferential direction. A first recess is arranged in the radially limiting wall of the interruption region downstream of the outlet. Further recesses are arranged in the interruption region before the axial inlet and after the outlet. A smallest distance between the further recesses is 0.5 to 3 times a distance between two conveying blades.

Abstract: This disclosure relates to a process for preparing D,L-methionine by feeding carbon dioxide to an aqueous potassium methioninate solution obtained by hydrolysis of 5-(2-methylmercaptoethyl)hydantoin, in order to precipitate out crude methionine, which is separated off and purified. In this process an aqueous solution of the separated-off crude methionine is purified by recrystallization from a solution containing potassium ions and also a crystallization additive. The crystallization additive is a nonionic or anionic surfactant, or a mixture of different nonionic or anionic surfactants. The recrystallization occurs by introducing a 60 to 110° C.-hot methionine solution into a 35 to 80° C.-warm methionine suspension, a temperature of which is lower than that of the introduced solution, such that the temperature of the methionine suspension being maintained between 35 and 80° C. during the addition. The crystallization additive is a sorbitan fatty acid ester or a mixture of different sorbitan fatty acid esters.

Abstract: The invention relates to a process for the preparation of D,L-methionine, in which carbon dioxide is fed to an aqueous potassium methioninate solution obtained by hydrolysis of 5-(2-methylmercaptoethyl)hydantoin, in order to precipitate out crude methionine, which is separated off and purified, where, for the purposes of purification, an aqueous solution of the separated-off crude methionine is prepared and subjected to a recrystallization, characterized in that the solution from which the recrystallization takes place contains potassium ions and also a crystallization additive, where the crystallization additive is a nonionic or anionic surfactant, or a mixture of different nonionic or anionic surfactants, and that the recrystallization takes place by introducing a 60 to 110° C.-hot methionine solution into a 35 to 80° C.-warm methionine suspension, the temperature of which is lower than that of the introduced solution, the temperature of the methionine suspension being maintained between 35 and 80° C.

Abstract: The invention relates to a process for the preparation of D,L-methionine, in which carbon dioxide is fed to an aqueous potassium methioninate solution obtained by hydrolysis of 5-(2-methylmercaptoethyl)hydantoin, in order to precipitate out crude methionine, which is separated off and purified, where, for the purposes of purification, an aqueous solution of the separated-off crude methionine is prepared and subjected to a recrystallization, characterized in that the solution from which the recrystallization takes place contains potassium ions and also a crystallization additive, where the crystallization additive is a nonionic or anionic surfactant, or a mixture of different nonionic or anionic surfactants, and that the recrystallization takes place by introducing a 60 to 110° C.-hot methionine solution into a 35 to 80° C.-warm methionine suspension, the temperature of which is lower than that of the introduced solution, the temperature of the methionine suspension being maintained between 35 and 80° C.

Abstract: The invention relates to a method and device for determining the static and/or dynamic scattering of light. In the method, a plurality of different zones within a sample vessel (6) is illuminated during various time periods, wherein light is scattered on the sample. The scattered light is detected by means of a plurality of detectors (11, 12, 13, 14), wherein during the implementation of the method each detector captures scattered light from a plurality of different zones, and during a time period each detector detects scattered light from one zone and generates a signal. Said signals are transmitted to an electronic evaluation unit and are processed by said unit, wherein in each case those signals which are generated by the same detector and result from the detection of scattered light from the same zone are processed together.

Abstract: A side channel blower includes a housing comprising a substantially tangential outlet. A housing cover comprises an axial inlet. At least one conveying duct is configured so that the axial inlet fluidly communicates with the outlet. An impeller is driven by a drive unit. The impeller is rotatably supported in the housing and comprises conveying blades which cooperate with the at least one conveying duct. An interruption region is arranged between the outlet and the axial inlet. The interruption region comprises a radially limiting wall and interrupts the at least one conveying duct in a circumferential direction. A first recess is arranged in the radially limiting wall of the interruption region downstream of the outlet. Further recesses are arranged in the interruption region before the axial inlet and after the outlet. A smallest distance between the further recesses is 0.5 to 3 times a distance between two conveying blades.

Abstract: A shrink disc is provided for the force-fit respectively friction-fit interconnecting of a shaft and a hollow shaft or the like having an interior compression ring (2), the outer circumferential surface of which has at least one conical surface (4), and at least one outer pressure ring (3) which in turn has at least one radially outward winding (10) consisting of a band and the inner circumferential surface of which comprises a conical surface (5) cooperating with the conical surface (4) of the compression ring (2) so that the compression ring (2) is compressed when axially tensioned. To manufacture the winding (10), the band is wrapped around the pressure ring (3) under tensile stress. This thus achieves being able to subject the shrink disc to higher loads.

Abstract: The invention relates to a method and device for determining the static and/or dynamic scattering of light. In the method, a plurality of different zones within a sample vessel (6) is illuminated during various time periods, wherein light is scattered on the sample. The scattered light is detected by means of a plurality of detectors (11, 12, 13, 14), wherein during the implementation of the method each detector captures scattered light from a plurality of different zones, and during a time period each detector detects scattered light from one zone and generates a signal. Said signals are transmitted to an electronic evaluation unit and are processed by said unit, wherein in each case those signals which are generated by the same detector and result from the detection of scattered light from the same zone are processed together.

Abstract: Ketomethionine ketals and hemiketals and derivatives thereof are useful as feed additives, in particular for the nutrition of ruminants.

Abstract: Ketomethionine ketals and hemiketals and derivatives thereof are useful as feed additives, in particular for the nutrition of ruminants.

Abstract: A device for protecting the electronic circuitry of electrical appliances against damage from unacceptably high voltages. An element is interposed in the power supply paths which limits the application of an externally supplied excessive voltage to a predetermined time interval and which completely interrupts the current flow when the excessive voltage and current causes a heat build-up. This is accomplished by interposing pairs of spaced-apart solder surfaces at at least one point along the current paths to the electronic circuitry. One solder surface of each pair is connected to the power supply and the other to the power consumer. An element is soldered to the respective solder surfaces of the pairs and electrically closes the current path. A mechanically prestressed spring engages the element and reliably separates it from the solder surfaces when the solder melts due to excessive heating.

Abstract: A tensioning coupler for a quill and shaft employs a yoke around the circumference of a quill, a first circumferential pressure ring and a second tensioning ring each of which has a projected conical portion which overlap each other when installed. Both rings have slots to allow them to be opened or closed slightly as the tensioning ring is drawn into the pressure ring.

Abstract: Process for the preparation of unsaturated 4,5-allene ketones by reaction of tertiary propargyl alcohols with alkenyl alkyl ethers or ketals in the presence of aliphatic sulfonic acids or sulfonic acid salts.

Abstract: An improvement in an electrical air pump having a housing with a pump mechanism at one end and an electric motor at the other end. The pump mechanism has at least one lightweight pump impeller made of plastic whose hub is press-fit on a shaft of the electric motor. The hub is provided with a plurality of grooves distributed around a bore in the hub which receives the motor shaft. The grooves form spaces between an inner surface of the hub and an outer surface of the shaft and the spaces are filled with an adhesive to bond the hub to the shaft. The grooves extend longitudinally or spirally along the entire length of the hub. The grooves are relatively shallow and have a depth of approximately 0.05 mm.

Abstract: An electrical air pump adapted for being periodically turned on and off and reversed in pumping direction. The air pump includes an electric motor adapted for electronic control and an air pump section joined by a housing as a common system. The housing has a cylindrical wall defining a first chamber in which the stator system is received and a scaling cover is engaged with the housing to seal the first chamber. The air pump section includes a pump cover sealingly engaged with the housing and defining therewith a second chamber, the rotor being of bell shape and rotatably supported in the second chamber on a pin secured in the housing and in the pump cover. The rotor is disposed with slight clearance adjacent to an end wall of the housing and the rotor projects radially beyond the cylindrical wall. The rotor has a collar and a plurality of pumping blades extending radially from the collar into an annular pumping channel of the second chamber.