Abstract: An NMR measuring arrangement (20) includes a cryostat (1), a superconducting magnet coil system (2) and an NMR probe (3). The cryostat has an evacuated vacuum container (5) and forms a bore (10). A wall (12) of the bore delimits the vacuum container. The cryostat forms only one evacuated gap (13) in a space (18) between the magnet coil system and the wall of the bore. At least a segment of the wall of the bore is thermally coupled to a heat sink of the cryostat. As a result, the NMR measurement arrangement provides more precise NMR measurements (in particular with a higher spectral resolution and/or a higher signal-to-noise ratio) on measurement samples.

Abstract: Temperature control system for an NMR sample tube (22) using a temperature control device (20) with an interior (21) delimiting a cylindrical wall (39) in the radially outward direction and a plurality of flow channels for temperature-controlling fluid running radially around the interior, of which the radially outermost flow channel (28) is delimited to the outside by a wall (29), and the innermost flow channel (31) by a wall (30) and connected to one another by a first fluid passage (34). The innermost flow channel has a second fluid passage (36) to the interior and the outermost flow channel has a fluid inlet (32). During operation, the wall delimiting the interior in the radially outward direction is temperature-controlled by the fluid so that: abs (TU?TW)?abs (TU?TFD), where TW is the wall temperature, TFD is the fluid temperature at the first fluid passage and TU is the ambient temperature.

Abstract: A superconductor magnet system (2) includes a cryostat (4), a superconductor bulk magnet (5), and a cryogenic cooling system (12). The bulk magnet (5) has at least N axially stacked bulk sub-magnets (6a-6c), with N?3. Between each two axially neighboring bulk sub-magnets, an intermediate body (7a-7b) is arranged. The intermediate bodies (7a-7b) are made from a non-metallic thermal insulator material. The cryogenic cooling system (12) is adapted for independently controlling the temperature of each bulk sub-magnet (6a-6c), and has, for each bulk sub-magnet, a temperature sensor (16a-16c) for sensing the temperature of the respective bulk sub-magnet and an adjustment unit (13a-13c) for adjusting a heating power and/or a cooling power at the respective bulk sub-magnet.

Abstract: A temperature-control system for an NMR magnet system. A permanent magnet arrangement (1) with a central air gap (2) generates a homogeneous static magnetic field inside the air gap. A probehead (3) transmits RF pulses and receives RF signals from a test sample (0). An H0 coil changes the amplitude of the static magnetic field. A shim system (4) in the air gap further homogenizes the magnetic field. A first insulation chamber (5) surrounds and thermally shields the permanent magnet arrangement and includes an arrangement (6) controlling a temperature T1 of the first insulation chamber. The shim system, the H0 coil and the NMR probehead are arranged outside the first insulation chamber in the air gap. A heat-conducting body (7) is arranged between the shim system and the H0 coil on one side and the permanent magnet arrangement on the other, thereby enhancing field stability and suppressing drift.

Abstract: A fastening device for releasably fastening a probe (1) to an NMR magnet (2). An insert part (3) fastens the probe to a retaining system (4) connected to the magnet. A force-variable connection is established by the insert part with spring elements (8). The probe fastens to the insert part with rigid retaining elements (6). When closed, a connection without mechanical play exists between the insert part and the retaining elements when the spring elements are under tension. An annular disc-shaped pretensioning element (9) is arranged between the insert part and the retaining system. By rotating the pretensioning element relative to the insert part, the pretensioning element presses on and pretensions the spring elements. When open, the spring elements and the retaining elements are configured to connect with a mechanical play of 0.5 to 5 mm between the insert part and the retaining elements when the spring elements are pretensioned.

Abstract: In a magnet system: —a superconducting main field magnet (7) generates a magnetic field in a first sample volume (16), —a superconducting additional field magnet (22) generates another field in a second sample volume (24), —a cryostat (2) has a cooled main coil container (6), an evacuated RT (room temperature) covering (4), and an RT bore (14) which extends through the main and the additional field magnets, and —a cooled additional coil container (21) in a vacuum. The RT covering has a flange connection (17) with an opening (19) through which the RT bore extends, a front end of the additional coil container protrudes through the opening into the RT covering such that the additional field magnet also protrudes through the opening into the RT covering, and a closure structure (20) seals the RT covering between the flange connection and the RT bore.

Abstract: A superconductor bulk magnet magnetizing method providing a more homogenous trapped magnetic field includes: placing the bulk magnet inside a charger bore of an electrical charger magnet; placing a field correction unit inside a superconductor bore of the bulk magnet; applying an electrical current (I0) to the charger magnet, to generate an externally applied magnetic field, wherein a temperature Tbulk of the bulk magnet exceeds a bulk magnet critical temperature Tc; applying an auxiliary electrical current (I1, . . . ) to the field correction unit, thus generating an auxiliary magnetic field applied to the bulk magnet from within the superconductor bore, wherein Tbulk>Tc; lowering Tbulk below Tc; turning off the electrical current at the charger magnet, wherein Tbulk<Tc, and turning off the auxiliary electrical current at the field correction unit, wherein Tbulk<Tc; and removing the bulk magnet from the charger bore while Tbulk<Tc.

Abstract: Charging method for a superconductor magnet system with reduced stray field, weight and space includes: arranging the system within a charger magnet bore; with Tmain>Tmaincrit and Tshield>Tshieldcrit, applying a current Icharger to the charger magnet and increasing Icharger to a first current I1>0; lowering a main superconductor bulk magnet temperature Tmain to an operation temperature Tmainop, with Tmainop<Tmaincrit, while keeping Tshield>Tshieldcrit; lowering Icharger to a second current I2<0, thereby inducing a persistent current IPmain in the main magnet; lowering a shield magnet temperature Tshield to an operation temperature Tshieldop, with Tshieldop<Tshieldcrit; increasing Icharger to zero, thereby inducing a persistent current IPshield in the shield magnet; removing the magnet system from the charger bore, and keeping Tmain?Tmainop with Tmainop<Tmaincrit and Tshield?Tshieldop with Tshieldop<Tshieldcrit; where: Tmaincrit: main magnet critical temperature and Tshieldcrit: shie

Abstract: A superconducting magnet assembly with a reinforced coil region (3) having a layered conductor coil assembly (10) forming cylindrical conductor layers (11, . . . ), each having plural circular conductor turns (12) centered around and aligned along the axis of cylindrical symmetry (z). The reinforced coil region further includes a layered corset coil assembly (20) having an inner radius bigger than an outer radius of the layered conductor coil assembly (10), and a corset sheet assembly (30) including a foil element forming a corset sheet (31, . . . ). A cross section of the corset sheet with any plane perpendicular to the z-axis forms a segmented circle centered around the z-axis, the radius of which is bigger than that of one of the conductor layers and smaller than that of another of the conductor layers. In addition, the segmented circle covers at least 90% of a full circle but has at most four segments. The assembly provides mechanical reinforcement against radial magnetic forces.

Abstract: A method for charging an HTS shim device in a cryostat having a room temperature bore using a charging device. A shim switch temporarily interrupts the superconducting state in a section of an HTS shim conductor path. The charging device includes a primary circuit with a normal-conducting charging coil and the conductor path forms a secondary circuit. A current change in the secondary circuit results from a change in magnetic flux generated by the charging coil through the secondary circuit. In a first phase the shim switch is opened to interrupt the superconducting state in a section of the conductor path, the charging coil is positioned in the bore, and the current in the primary circuit is changed; in a second phase, the conductor path is superconductingly closed; in a third phase, the current in the primary circuit is changed and/or the charging coil is removed from the bore.

Abstract: A shim device having an HTS shim conductor track (C) and a shim switch (Sw1) The track (C) is curved around an axis (z) and the shim switch is arranged in a first conductor track portion (S1), to interrupt its superconducting state. The track (C) extends around at least a first opening (O1) and a second opening (O2) such that the track (C) has a first circumferential current path (L1), a second circumferential current path (L2) and a third circumferential current path (L3). Two of the three paths (L1, L2, L3) each surround only one of the two openings and one of the three paths (L1, L2, L3) surrounds both openings. The first portion (S1) is part of only the first path (L1) and the second path (L2). This produces a persistent HTS shim for field homogenization, allowing both a complex field distribution and a large degree of design freedom.

Abstract: A magnet assembly in a magnetic resonance apparatus includes a cryostat and a superconducting main field magnet coil system arranged therein for generating a magnetic field in the direction of a z-axis in a working volume. The magnet assembly includes a shim device arranged inside the cryostat for adjusting the spatial variation or homogeneity of the magnetic field generated in the working volume by the magnet coil system. The shim device comprises at least one closed superconducting shim conductor path having an HTS layer. The HTS layer forms a surface that is geometrically developable such that unwrapping onto a plane changes the geodesic distance between any two points on the surface formed by the HTS layer by no more than 10%. The inner and/or outer contour of the geometrical development of the HTS layer describes a non-convex curve.

Abstract: A cryostat assembly with an outer container for a storage tank with a first cryogenic fluid and a coil tank for a superconducting magnet coil system. The magnet coil system is cooled by a second cryogenic fluid colder than the first cryogenic fluid, the coil tank being mechanically connected to the outer container and/or to radiation shields surrounding the coil tank via a mounting structure. Liquid helium at an operating temperature of approximately 4.2 K is the first cryogenic, fluid and helium at an operating temperature of <3.5 K is the second cryogenic fluid in the coil tank. The mounting structure has mounting elements with thermally conductive contact points thermally coupled to heat sinks having a temperature at or below that of the storage tank, via thermal conductor elements. This ensures long times to quench if malfunctions occur.

Abstract: An NMR spectrometer (1) with a magnet system (2), which has a bore (3) through the magnet center (4) for inserting a measuring sample (5) in a transport container (7), and with a transport device for pneumatic transport of the sample through a transport channel (8) into and out of the magnet system. The transport device includes a mechanical interface (9) with a mounted exchange system (10) which has parking receptacles (11) temporarily storing the transport containers. In a transport position, the parking receptacle is inserted into the transport channel, to be loaded with a transport container, removed from the transport channel for temporarily storing the transport container, and reinserted into the transport channel for further transport of the transport container. In the transport position, the parking receptacle forms a part of the transport channel, which permits a faster automated change of the measuring samples in short measurement cycle times.

Abstract: A reinforced superconducting wire (1a) has a superconducting core strand (2) and a first cladding with a multitude of reinforcing strands (3). The reinforcing strands (3) are arranged around the circumferential surface of the superconducting core strand (2) in a non-crossing manner and are in contact with the core strand (2). The wire has a reinforcement for enhancing its mechanical properties against external stresses and for preventing diameter expansion during heat treatment. In addition to other advantages, such superconducting wire can be produced with an easy and low-cost production process.

Abstract: A superconductor magnet apparatus (2) includes a superconductor bulk magnet (9), a cryostat (7) and a ferromagnetic shielding body (11). The bulk magnet has a superconductor bore (10), an axis (z) of rotational symmetry, and a maximum outer diameter ODbm in a plane perpendicular to the z axis. The superconductor bore has a minimum cross-sectional area Sbo in a plane perpendicular to the z axis. The cryostat has a room temperature bore (8), the bulk magnet is arranged within the cryostat and the room temperature bore is arranged within the superconductor bore. The shielding body has a shielding bore (12), the bulk magnet is arranged within the shielding bore and the shielding body extends beyond the bulk magnet at each axial end by at least ODbm/3. For an average cross-sectional area Sfb of the shielding body, Sfb?2.5*Sbo, and the shielding body is arranged within the cryostat.

Abstract: A read network topology for a matrix output device with a number of outputs determined by cross-joining “m” rows and “n” columns comprises a basic filtering block replicated for all the outputs and separately assigned to each of the outputs; each filtering block contains two filtering circuits that have a common input connection to the assigned matrix output and that provide two separate symmetrical and filtered outputs; all the row outputs (i) from the same row “i” but from different columns are interconnected to an input of an amplifier linked to row “i”, and all the column outputs (j) from the same column “j” but from different rows are connected together to an input of an amplifier linked to column “j”, the complete topology appearing when “i” and “j” are expanded in the respective intervals thereof.

Abstract: A magnet assembly (1) with a cryostat (2) has a superconducting magnet coil system (3), an active cooling device (4) for the coil system, and current leads (5a, 5b) for charging the coil system. The current leads have at least one normal-conducting region (15a, 15b), wherein multiple cold reservoirs (20) are thermally coupled to the current leads along the normal-conducting region thereof, in order to absorb heat the normal-conducting region during charging of the magnet coil system. The current leads have a variable cross-sectional area B in the normal-conducting region along the extension direction thereof, wherein at least over a predominant fraction of their overall length in the normal-conducting region, the cross-sectional area B decreases from a cold end (18a, 18b) toward a warm end (19a, 19b). This provides a magnet assembly requiring reduced cooling power during charging, with less heat introduced into the magnet coil system in normal operation.

Abstract: A first radial bearing includes nozzles in the stator at a radius r1 and a bearing surface on a circular section of the rotor at a radius R1. A second radial bearing includes nozzles in the stator at a radius r2 and a bearing surface on the rotor at a radius R2. An axial bearing includes a nozzle in the stator and a bearing surface on an axial end of the rotor, which runs orthogonally to the rotation axis and has an outer radius R3. The second radial bearing is formed on an end section of the rotor, which has a smaller radius than or a radius that decreases away from the circular section, so that R2<R1 and r2<r1. The third bearing surface is formed on an end of the end section facing away from the circular section, so that R3?R2.

Abstract: Transport apparatus pneumatically conveying NMR test samples (2) from or to an NMR spectrometer (1) through a tubular transport channel (3) includes a device (4) generating positive pressure in the end of the transport channel that is remote from the spectrometer. The transport channel has a tube system which has a gas-tight outer tube (5) having an outer diameter Da and an inner diameter da and an inner tube (6), arranged coaxially with respect to the outer tube, having an outer diameter Di<da and an inner diameter di. The inner diameter di of the inner tube is greater than or equal to the outer diameter DP of the test samples, and the inner tube includes mutually spaced cross-holes (7) designed as through-holes. This provides accurate current position determinations for the sample in the transport channel, and reduced risk of damaging the sample during transport.