Abstract: A method for operating an NMR probehead (10) with an MAS stator (11) receiving a circular-cylindrical hollow MAS rotor (13) with an outer jacket. The MAS rotor is mounted on pressurized gas in a measuring position within the MAS stator via a gas supply device with a bearing nozzle (12?) and rotates about the cylinder axis of the MAS rotor at a rotation frequency f?30 kHz. During a measurement, a temperature control gas is blown by a temperature control nozzle (12) onto the outer jacket of the rotor at an angle ?<90° with respect to the longitudinal axis of the cylinder-symmetrical rotor. The flow speed of the temperature control gas corresponds in the nozzle cross section to at least half the circumferential speed of the outer jacket of the rotating rotor and to at most the speed of sound in the temperature control gas.

Abstract: A nuclear magnetic resonance-magic angle spinning (NMR-MAS) turbine assembly has a MAS rotor with turbine cap having a stopper region and a turbine region. The stopper region allows feeding into a rotor tube and has at least one sealing section for resting against an inner wall of the rotor tube. The turbine region has a collar section for resting against a face side of the rotor tube and a turbine section that forms the turbine blades, which protrude axially from the collar section without extending radially further than the collar section. The arrangement of the rotor allows for very high rotation frequencies that, correspondingly, reduce line broadening in NMR measurements.

Abstract: An MAS stator (7) for an NMR-MAS probe head (1) has a bottom bearing (8) with at least one nozzle and at least one radial bearing (9a, 9b), wherein one substantially circular cylindrical MAS rotor (21c) is provided for receiving a measurement substance. The MAS rotor can be supported by compressed gas in a measurement position within the MAS stator by means of a gas supply device and can be rotated about the cylinder axis of the MAS rotor by means of a pneumatic drive. A suction device (100) is provided in a space below the radial bearing for suctioning-off the gas introduced by the gas supply device, and generates an underpressure in the space below the radial bearing during measurement operation. This provides a stator for NMR-MAS spectroscopy in which the closure at the head end of the stator is omitted.

Abstract: A method for operating an NMR probehead (10) with an MAS stator (11) receiving a circular-cylindrical hollow MAS rotor (13) with an outer jacket. The MAS rotor is mounted on pressurized gas in a measuring position within the MAS stator via a gas supply device with a bearing nozzle (12?) and rotates about the cylinder axis of the MAS rotor at a rotation frequency f?30 kHz. During a measurement, a temperature control gas is blown by a temperature control nozzle (12) onto the outer jacket of the rotor at an angle ?<90° with respect to the longitudinal axis of the cylinder-symmetrical rotor. The flow speed of the temperature control gas corresponds in the nozzle cross section to at least half the circumferential speed of the outer jacket of the rotating rotor and to at most the speed of sound in the temperature control gas.

Abstract: An NMR MAS probe head (1) has an MAS stator (7) with a base bearing (8) and a front bearing (75) for receiving a substance to be measured at a measurement position within an MAS rotor. The front bearing has an opening for inserting the MAS rotor into the space between the base bearing and the front bearing. The opening can be closed by a closing device that, in a loading state, opens and, in a measuring state, closes the opening by means of a movement that is transverse with respect to an axis (a) through the centers of the base bearing and the opening of the front bearing of the MAS stator. This enables automated loading and unloading of the MAS rotor in the space between the base bearing and the front bearing inside the MAS stator in a simple way.

Abstract: A nuclear magnetic resonance-magic angle spinning (NMR-MAS) turbine assembly has a MAS rotor with turbine cap having a stopper region and a turbine region. The stopper region allows feeding into a rotor tube and has at least one sealing section for resting against an inner wall of the rotor tube. The turbine region has a collar section for resting against a face side of the rotor tube and a turbine section that forms the turbine blades, which protrude axially from the collar section without extending radially further than the collar section. The arrangement of the rotor allows for very high rotation frequencies that, correspondingly, reduce line broadening in NMR measurements.

Abstract: An MAS stator (7) for an NMR-MAS probe head (1) has a bottom bearing (8) with at least one nozzle and at least one radial bearing (9a, 9b), wherein one substantially circular cylindrical MAS rotor (21c) is provided for receiving a measurement substance. The MAS rotor can be supported by compressed gas in a measurement position within the MAS stator by means of a gas supply device and can be rotated about the cylinder axis of the MAS rotor by means of a pneumatic drive. A suction device (100) is provided in a space below the radial bearing for suctioning-off the gas introduced by the gas supply device, and generates an underpressure in the space below the radial bearing during measurement operation. This provides a stator for NMR-MAS spectroscopy in which the closure at the head end of the stator is omitted.

Abstract: An NMR MAS probe head (1) has an MAS stator (7) with a base bearing (8) and a front bearing (75) for receiving a substance to be measured at a measurement position within an MAS rotor. The front bearing has an opening for inserting the MAS rotor into the space between the base bearing and the front bearing. The opening can be closed by a closing device that, in a loading state, opens and, in a measuring state, closes the opening by means of a movement that is transverse with respect to an axis (a) through the centers of the base bearing and the opening of the front bearing of the MAS stator. This enables automated loading and unloading of the MAS rotor in the space between the base bearing and the front bearing inside the MAS stator in a simple way.

Abstract: A nuclear magnetic resonance (NMR) magic angle spinning (MAS) probe head (1; 61) for measuring a measuring substance in an MAS rotor (21a-21c), comprises a bottom box (3) and a tube (2) mounted to the bottom box (3) and projecting from the bottom box, wherein, in the area of the end (5) of the tube (2) facing away from the bottom box (3), an MAS stator (7; 62) is disposed within the tube (2) for receiving an MAS rotor (21a-21c), and with a pneumatic sample changing system for supplying and discharging an MAS rotor (21a-21c) to/from the MAS stator (7; 62). A transport conduit (10) is provided for pneumatically transferring an MAS rotor (21a-21c) within the transport conduit (10), wherein the transport conduit (10) extends in the inside of the tube (2) from the bottom box (3) to the MAS stator (7; 62). The probe head realizes fast change between different MAS rotors and facilitates RF shielding and keeping of defined extreme temperature conditions.

Abstract: A nuclear magnetic resonance (NMR) magic angle spinning (MAS) probe head (1; 61) for measuring a measuring substance in an MAS rotor (21a-21c), comprises a bottom box (3) and a tube (2) mounted to the bottom box (3) and projecting from the bottom box, wherein, in the area of the end (5) of the tube (2) facing away from the bottom box (3), an MAS stator (7; 62) is disposed within the tube (2) for receiving an MAS rotor (21a-21c), and with a pneumatic sample changing system for supplying and discharging an MAS rotor (21a-21c) to/from the MAS stator (7; 62). A transport conduit (10) is provided for pneumatically transferring an MAS rotor (21a-21c) within the transport conduit (10), wherein the transport conduit (10) extends in the inside of the tube (2) from the bottom box (3) to the MAS stator (7; 62). The probe head realizes fast change between different MAS rotors and facilitates RF shielding and keeping of defined extreme temperature conditions.