Abstract: The invention relates to a process for the preparation of di- and polyamines of the diphenylmethane series (MDA), in which firstly crude MDA is prepared and is then subjected to a distillation process, wherein the distillation process comprises the following: in a distillation column, separating off a stream containing aniline and water as head product so as to obtain the first product stream as sump product, in said distillation column or in an apparatus arranged downstream of said distillation column, performing a stripping with steam so as to obtain a gaseous stream containing aniline, water and MMDA, partially condensing this gaseous stream containing aniline, water and MMDA so as to obtain a liquid stream containing MMDA and water (and optionally aniline) and a gaseous stream containing aniline and water (and optionally MMDA), drying the liquid stream containing MMDA and water (and optionally aniline) obtained by the partial condensation so as to obtain the second product stream.

Abstract: The invention relates to a process for the preparation of di- and polyamines of the diphenylmethane series (MDA), in which firstly crude MDA is prepared and is then subjected to a distillation process, wherein the distillation process comprises the following: in a distillation column, separating off a stream containing aniline and water as head product so as to obtain the first product stream as sump product, in said distillation column or in an apparatus arranged downstream of said distillation column, performing a stripping with steam so as to obtain a gaseous stream containing aniline, water and MMDA, partially condensing this gaseous stream containing aniline, water and MMDA so as to obtain a liquid stream containing MMDA and water (and optionally aniline) and a gaseous stream containing aniline and water (and optionally MMDA), drying the liquid stream containing MMDA and water (and optionally aniline) obtained by the partial condensation so as to obtain the second product stream.

Abstract: A method for generating motion information for an at least partially moving examination region includes outputting at least one first excitation signal with a first frequency band. The first excitation signal is picked up with a receive coil arrangement of a magnetic resonance system. The at least one coil of the receive coil arrangement is configured to pick up a receive frequency band that includes the first frequency band. At least one item of motion information for the examination region is determined from the picked up first excitation signal.

Abstract: A magnetic resonance tomography system includes a plurality of MRT plugs for connection of antenna elements, respectively, of one of a plurality of local coils. Due to at least one analog switch matrix, antenna elements respectively connected to fewer than all of the MRT plugs may be connected in an analog fashion to receive signal processing elements of one of a plurality of receive signal processing element blocks respectively having a plurality of receive signal processing elements. Between outputs of receive signal processing element blocks and an evaluation device of the magnetic resonance tomography system, a digital channel selection unit is provided. On an input side of the digital channel selection unit, the digital channel selection unit may be connected to antenna elements. Signals from fewer antenna elements are present at the output of the digital channel selection unit than at an input of the digital channel selection unit.

Abstract: The invention relates to a process for producing polyether carbonate polyols through an addition reaction of alkylene oxides and carbon dioxide onto one or more H-functional starter substances in the presence of a double metal cyanide catalyst or in the presence of a metal complex catalyst based on the metals zinc and/or cobalt, characterized in that one or more H-functional starter substances containing at least 1000 ppm of component (K) is/are continuously metered into the reactor during the reaction, where component (K) is selected from at least one compound containing a phosphorus-oxygen bond and a phosphorus compound that can form one or more P—O bonds through reaction with OH-functional compounds.

Abstract: A magnetic resonance apparatus has a computer designed to emit, on each of at least one control channel, a control signal generated from a sequence of values to control, via each channel, at least one component of the magnetic resonance apparatus. A buffer device is provided for each channel, which includes at least one read control device and a control buffer memory for that control channel. A software tool running on the computer is designed to determine the values as a function of predefined parameters and write them to the control buffer memory. The read control device is designed to read values from the control buffer memory and to supply them, with a read clock derived from a clock that was set independently of the computer, to the respective component. For each of the control buffer memories, the order in which the values are read corresponds to the order in which they are written.

Abstract: The present invention relates to the use of a component A for the production of colour-stable polyurethane foams, containing A1?50 to ?100 weight parts of at least one polyether carbonate polyol with a hydroxyl number from ?20 mg KOH/g to ?300 mg KOH/g according to DIN 53240, A2?50 to ?0 weight parts of at least one polyether polyol with a hydroxyl number from ?20 mg KOH/g to ?250 mg KOH/g according to DIN 53240, wherein the polyether polyol is free from carbonate units, A3 0.5 to 25 weight parts, based on the sum of the weight parts of components A1 and A2, water and/or physical propellants, A4 0 to 10 weight parts, based on the sum of the weight parts of components A1 and A2, at least one antioxidant, A5 0 to 10 weight parts, based on the sum of the weight parts of components A1 and A2, adjuvants and additives, wherein all weight part data of the components A1 to A5 are scaled such that the sum of the weight parts A1+A2 is 100 in the composition.

Abstract: An isocyanate-terminated prepolymer C having an NCO content of from ?26% by mass to ?31.0% by mass is obtainable from the reaction of an isocyanate composition A having a viscosity at 25° C. of from ?60 mPas to ?800 mPas, comprising from ?25% by mass to ?60% by mass MDI and from ?40% by mass to ?75% by mass pMDI, wherein the sum of the amounts of those components is ?100% by mass, with a bifunctional polyester ether polyol B having an OH number of ?200 mg(KOH)/g and ?500 mg(KOH)/g, obtained from the reaction of a dicarboxylic acid/dicarboxylic acid derivative with at least one polyol and with an epoxide, wherein the polyester ether polyol B is used in amounts of from ?1.5% by mass to ?6.0% by mass, based on the sum of the masses of A and B. The invention further provides a PUR/PIR polymer produced from the prepolymer C, its use and composite elements based thereon.

Abstract: The invention relates to a process for producing polyether carbonate polyols through an addition reaction of alkylene oxides and carbon dioxide onto one or more H-functional starter substances in the presence of a couble metal cyanide catalyst or in the presence of a metal complex catalyst based on the metals zinc and/or cobalt, characterized in that one or more H-functionalstarter substances containing at least 1000 ppm of component (K) is/are continuously metered into the reactor during the reaction, where component (K) is selected from at least one compound containing a phosphorus-oxygen bond and a phosphorus compound that can form one or more P—O bonds through reaction with OH-functional compounds.

Abstract: A method for generating motion information for an at least partially moving examination region includes outputting at least one first excitation signal with a first frequency band. The first excitation signal is picked up with a receive coil arrangement of a magnetic resonance system. The at least one coil of the receive coil arrangement is configured to pick up a receive frequency band that includes the first frequency band. At least one item of motion information for the examination region is determined from the picked up first excitation signal.

Abstract: A magnetic resonance tomography (MRT) system has a receive apparatus disposed in a magnetic field, in which a receive coil is coupled to an input of an analog/digital converter. The analog/digital converter is configured for this purpose. A digital output of the analog/digital converter is coupled via a digital mixer device and a clock-rate-reduction device to a data output of the receive apparatus. The mixer device is configured to mix a predetermined frequency band of the MR signal downwards into an intermediate frequency range and create a digital IF signal.

Abstract: A magnetic resonance tomography system includes a plurality of MRT plugs for connection of antenna elements, respectively, of one of a plurality of local coils. Due to at least one analog switch matrix, antenna elements respectively connected to fewer than all of the MRT plugs may be connected in an analog fashion to receive signal processing elements of one of a plurality of receive signal processing element blocks respectively having a plurality of receive signal processing elements. Between outputs of receive signal processing element blocks and an evaluation device of the magnetic resonance tomography system, a digital channel selection unit is provided. On an input side of the digital channel selection unit, the digital channel selection unit may be connected to antenna elements. Signals from fewer antenna elements are present at the output of the digital channel selection unit than at an input of the digital channel selection unit.

Abstract: A system for optical data transmission has at least a first optical data transmission component that has a first optical data receive unit. They system further has a second optical data transmission component that has a first optical data transmit unit, and the system further has at least one optical waveguide, through which the first optical data receive unit and the first optical data transmit unit connected and through which data are transmitted from the first optical data transmit unit to the first optical data receive unit. The first optical data receive unit has a first light power measuring unit for measuring the light power transmitted through the at least one optical waveguide, and the first light power measuring unit is designed to generate an electrical status signal depending on the measured light power, and to make that signal available to a first control unit.

Abstract: A magnetic resonance apparatus has a computer designed to emit, on each of at least one control channel, a control signal generated from a sequence of values to control, via each channel, at least one component of the magnetic resonance apparatus. A buffer device is provided for each channel, which includes at least one read control device and a control buffer memory for that control channel. A software tool running on the computer is designed to determine the values as a function of predefined parameters and write them to the control buffer memory. The read control device is designed to read values from the control buffer memory and to supply them, with a read clock derived from a clock that was set independently of the computer, to the respective component. For each of the control buffer memories, the order in which the values are read corresponds to the order in which they are written.

Abstract: A method for operating a coil, through which a varying current flows, is provided. Mechanical resonance responses of the coil are recorded and are modeled by an electrical resonant circuit model. A check is made as to whether a varying current that is to be sent through the coil evokes a resonant response in the electrical resonant circuit model. The current flow through the coil is blocked if the resonant response exceeds a predefined limit value.

Abstract: The present invention relates to a process for producing flexible polyurethane (PUR) foams with high comfort value and low hysteresis losses produced by reacting organic polyisocyanates containing di- and polyisocyanates of the diphenylmethane (MDI) group with polyoxyalkylene polyethers.

Abstract: Aromatic amines are produced by adiabatic hydrogenation of nitroaromatic compounds in the gas phase on one or more fixed catalysts. The nitroaromatic reactant is passed over the catalyst under pressure and at elevated temperature with hydrogen, water, optionally nitrogen and substantially in the absence of the aromatic amine produced from the nitroaromatic.

Abstract: The present invention relates to the technical field of isocyanates. The present invention provides a method for preparing NCO prepolymers by reacting a stoichiometric excess of an organic isocyanate with an isocyanate-reactive component, the reaction components being mixed together and the mixture being introduced directly into a storage or transport vessel, where it reacts to completion.

Abstract: A method for operating a coil, through which a varying current flows, is provided. Mechanical resonance responses of the coil are recorded and are modeled by an electrical resonant circuit model. A check is made as to whether a varying current that is to be sent through the coil evokes a resonant response in the electrical resonant circuit model. The current flow through the coil is blocked if the resonant response exceeds a predefined limit value.

Abstract: An isocyanate-terminated prepolymer C having an NCO content of from ?26% by mass to ?31.0% by mass is obtainable from the reaction of an isocyanate composition A having a viscosity at 25° C. of from ?60 mPas to ?800 mPas, comprising from ?25% by mass to ?60% by mass MDI and from ?40% by mass to 75% by mass pMDI, wherein the sum of the amounts of those components is ?100% by mass, with a bifunctional polyester ether polyol B having an OH number of ?200 mg(KOH)/g and ?500 mg(KOH)/g, obtained from the reaction of a dicarboxylic acid/dicarboxylic acid derivative with at least one polyol and with an epoxide, wherein the polyester ether polyol B is used in amounts of from ?1.5% by mass to ?6.0% by mass, based on the sum of the masses of A and B. The invention further provides a PUR/PIR polymer produced from the prepolymer C, its use and composite elements based thereon.