Abstract: A heat pipe having a working chamber having an evaporator region operatively connected to a heat source, and a condenser region operatively connected to a heat sink. A working fluid is provided in the working chamber, and heat is transferred from the heat source to the heat sink by the working fluid in a first state of operation. The heat pipe is a switchable and/or programmable thermal diode or a switchable and/or programmable heat switch, at least one activatable functional material is provided, which is arranged and configured to keep the evaporator region free of the working fluid and/or to prevent the working fluid from evaporating in a second state of operation, in order to reduce and/or hinder heat transfer and/or to alter the preferential direction of heat conduction. A system and method for switching and/or programming heat transfer in a heat pipe are also provided.

Abstract: A method for producing a thermoelectric module (1) having an inner tube (2), and an outer tube (8), and at least two thermoelectric base elements (5), the method including providing the thermoelectric base elements (5) outside the inner tube (2) or inside the outer tube, and widening the inner tube (2) and/or shrinking the outer tube (8). At least one plastically or elastically deformable functional layer is applied between the inner tube (2) and the thermoelectric base elements (5) and/or between the thermoelectric base elements (5) and the outer tube (8) before the widening/shrinking, and the thermoelectric base elements (5) are operatively connected to the functional layer parallel to the inner tube (2), such that an interference fit assembly is produced by the widening of the inner tube (2) and/or the shrinkage of the outer tube (8).

Abstract: A method for stabilization and/or control and/or regulation of the working temperature of a cyclic-process-based system having at least one heat-exchanger unit with at least one calorically active material element. It is essential that a base temperature of the calorically active material element (11, 12) is controlled by a cooling fluid. A heat-exchanger unit, a refrigeration machine, and a heat pump according to this are also provided.

Abstract: An exhaust-gas aftertreatment system for an internal combustion engine, having a catalyst device, which is designed to catalytically react at least one exhaust-gas component with a reactant, and a reactant-metering device, which is arranged upstream of the catalyst device along a flow path of the exhaust gas through the exhaust-gas aftertreatment system. The reactant-metering device has at least one exhaust-gas flow nozzle.

Abstract: An exhaust-gas aftertreatment system for an internal combustion engine, having a catalyst device, which is designed to catalytically react at least one exhaust-gas component with a reactant, and a reactant-metering device, which is arranged upstream of the catalyst device along a flow path of the exhaust gas through the exhaust-gas aftertreatment system. The reactant-metering device has at least one exhaust-gas flow nozzle.