Abstract: A cooling device (1) has a cryostat (2) and a cold head (3) of a cooling system (52), and additionally includes a pivot bearing (35), with which the cold head (3) is mounted on the cryostat (2) so as to be rotatable about a rotation axis (A). A connecting line (15) for a working gas of the cooling system (52) is connected to the cold head so that forces caused by the cooling system (52) act on the cold head (3) via the connecting line (15) at a force application point (EP) in a force application direction (ER). The force application direction (ER) is inclined by no more than 40° with respect to the normal (N) of a lever plane (HE) which contains the rotation axis (A) and the force application point (EP).

Abstract: A fastening system for attaching an NMR probe to an NMR magnet includes a discoid insert and a retention system that is rigidly connected to the magnet and on which the insert can be mounted. A form-fitting, variable-force connection is established between the NMR probe and the retention system using a spring element. The probe attaches to the insert by a plurality of integral, rigid retaining elements that are of an invariable fixed length. The spring element and the retaining elements are designed geometrically such that in a first, opened state the connection between the insert and the retaining elements has a mechanical backlash between 0.5 mm and 5 mm when the spring element is relaxed. In a second, closed state the connection between the insert and the retaining elements has no mechanical backlash when the spring element is under mechanical tension.

Abstract: A layer wound magnet coil includes a central coil region and end coil regions adjoining the central coil region along an axial line of symmetry. The central coil region includes layers of coil windings of an anisotropic material. The end coil regions include layers of coil windings of the anisotropic superconducting material interspersed with layers of non-superconducting material.

Abstract: A nuclear magnetic resonance coil configuration having at least one flat or cylindrical coil (18), through which current flows in operation, which coil generates a high-frequency magnetic B1 field at the location of a sample (16) which is oriented parallel to an x-axis, and which for the purpose of connection to a tuning network is connected to at least two electrical feed lines (11), through which in-phase currents flow in operation, and which generate a high-frequency magnetic B2 field in the sample (16), the orientation of which encloses an angle ? with the direction of the B1 field, is characterized in that the following applies for the angle ?: ?=180°±??, where ??<90°. In this way, a B1 field profile, which is as rectangular as possible and is particularly steep on both sides, can be generated.

Abstract: An HF resonator assembly generates at least two independent alternating magnetic fields in a test volume of a magnetic resonance apparatus. The HF resonator assembly includes a first pair of flat coils that form a first HF resonator and comprise electrical conductor portions that surround a planar surface portion. The flat coils are arranged on opposing sides of the test volume, on coil support plates that are mutually parallel and in parallel with the longitudinal axis. A second pair of flat coils forms a second HF resonator on second coil support plates. The projections of the planar surface portions of the flat coils in each of the first pair of flat coils and the second pair of flat coils overlap in part, but not completely, when viewed in a direction perpendicular to the respective planar surface portions.

Abstract: A probehead of an NMR-MAS apparatus includes a sample which has a rotation axis tilted by an angle ?>0 with respect to the z-axis. The angle ? can be adjusted about a target angle ?target by tilting around a tilt axis. The rotation axis has a fixed angle with respect to the probehead, and the NMR-MAS apparatus tilts at least part of the probehead to adjust the angle ?. The probehead has an outer contour K between an upper end and a lower end. For all z between the upper end and the lower end, a cross-section S(z) of the contour K exists parallel to the xy-plane with a width Q(z) in the x-direction. The width Q(z) is smaller at points away from z=0, such that Q(z1)<Q(0) and Q(z2)<Q(0) for z1<0 and z2>0.

Abstract: This disclosure describes an imaging radiation detection module with novel configuration of the scintillator sensor allowing for simultaneous optimization of the two key parameters: detection efficiency and spatial resolution, that typically cannot be achieved. The disclosed device is also improving response uniformity across the whole detector module, and especially in the edge regions. This is achieved by constructing the scintillation modules as hybrid structures with continuous (also referred to as monolithic) scintillator plate(s) and pixelated scintillator array(s) that are optically coupled to each other and to the photodetector.

Abstract: A method for the transmission/reception of RF signals for NMR measurements uses a heat exchanger (1) for cooling heat sources (5), the heat exchanger having a contact element (4.2) for thermal connection between a cryogenic fluid and the heat source, is characterized in that the heat exchanger comprises a container having an interior volume VB into which a first cryogenic fluid F1 that has a liquid component F1L and a gaseous component F1G flows through an inflow conduit (8) and from which a second cryogenic fluid F2 that has liquid component F2L and a gaseous component F2G flows out through an outflow conduit (9). The inflow conduit has a flow cross-section QZ and a circumference UZ from which an associated parameter VZ=4·Q2Z/UZ results, wherein VB>10·VZ, and the outflow conduit has a flow diameter QA wherein QA?QZ. The contact element is in close thermal contact with both the liquid volume component VL of the cryogenic fluid and with the heat source.

Abstract: An NMR probe head (1) comprising one or more HF coils (2) arranged around a vertical axis of symmetry (z), and an HF network (3) surrounded by an apparatus (4) for shielding from external HF radiation comprising an electrically conductive shielding tube (5) arranged along a z-axis and that can be moved around the HF coils and the HF network in a z direction towards a base disc (6)A shielding disc (7) is provided at an axial distance from the base disc, wherein a tensible HF seal (8) is arranged between the shielding disc and the shielding tube. When the shielding tube is in a mounted state, the HF seal, in a first mounting state, can slide over the shielding disc in an unbraced and force-free manner. When the HF seal is in a second mounting state, the HF seal is mechanically braced between the shielding disc and the shielding tube to ensure an electrically conductive connection.

Abstract: The invention relates to a hybrid medical PET-SPECT/MR imaging device comprising at least one scintillating crystal and at least one module for detecting radiation which contains at least one matrix of photodetectors and an electronics section, such that said module has a mechanical structure, the external, internal or both surfaces of which are divided into at least two sections, of which at least one is coated in graphene, and the rest in non-ferromagnetic conductive material, or all the sections are coated in graphene, and such that the coating forms a Faraday cage. The invention also relates to a shielding against radiofrequency for a medical imaging device, comprising a graphene coating, which is continuous or in bands, on all the faces of the mechanical structure of the detection module of the device, or a graphene coating, continuous or in bands, on at least one face, combined with a coating of non-ferromagnetic conductive materials on the remaining faces, and said shielding forming a Faraday cage.

Abstract: A superconducting magnet assembly includes a cryostat, a vacuum vessel and a refrigeration stage. An NMR probe using the assembly includes comprises cooled probe components, a two-stage cryocooler, and a counter flow heat exchanger. A cooling circuit guides coolant from one outlet of the counter flow heat exchanger back to an inlet of the counter flow heat exchanger via the second cooling stage, a cooled probe component, and a heat exchanger in the cryostat or a heat exchanger in a helium suspension tube. Both the intake temperature of the coolant flowing into the heat exchanger in the cryostat or in the suspension tube and the return flow temperature of the emerging coolant are at least 5 K lower than the operating temperature of the first cooling stage. Excess cooling capacity of the cryocooler reduces the evaporation rate of liquid helium or cools a superconducting magnet in a cryogen-free cryostat.

Abstract: An NMR apparatus includes a superconducting magnet assembly, a cryostat having a vacuum vessel, a refrigeration stage that can be operated at a temperature of <100 K, and a magnet coil system that comprises a cold bore into which a room temperature access of the cryostat engages. The NMR apparatus also includes an NMR probe with probe components cooled to an operating temperature of <100 K. The probe components are arranged between the cold bore and the room temperature access into the cold bore, radially inside the cold bore but outside the room temperature access. The vacuum vessel includes an opening that can be closed by a lock valve. A lock chamber is directly connected to the opening, such that the cooled probe components can be installed and/or removed through the opening and lock valve without breaking the vacuum in the vacuum vessel of the cryostat.

Abstract: A probehead of an NMR-MAS apparatus with a rotation axis (RA), which lies in an xz-plane, titled by an angle ?>0 relative to a z-axis. The angle ? is adjusted by tilting around a tilt axis (DA) parallel to the y-axis relative to a target angle ?target. An angle measurement apparatus (9) has a first sensor element (7), which, together with a second sensor element (8) generates sensor signals dependent on the amplitude B0 of the static magnetic field and the vectorial orientation between the magnetic field B0 and a sensitivity vector. Two sensitivity vectors have an angle 5°<?i<175° to the z-axis and an angle ?>10° to each other. The angle between the rotation axis and the z-axis can be measured precisely and reliably over a large range, providing a feedback signal for regulated adjustment or tracking of the angle ?.

Abstract: A superconducting magnet assembly includes a cryostat, a vacuum vessel and a refrigeration stage. An NMR probe using the assembly includes comprises cooled probe components, a two-stage cryocooler, and a counter flow heat exchanger. A cooling circuit guides coolant from one outlet of the counter flow heat exchanger back to an inlet of the counter flow heat exchanger via the second cooling stage, a cooled probe component, and a heat exchanger in the cryostat or a heat exchanger in a helium suspension tube. Both the intake temperature of the coolant flowing into the heat exchanger in the cryostat or in the suspension tube and the return flow temperature of the emerging coolant are at least 5 K lower than the operating temperature of the first cooling stage. Excess cooling capacity of the cryocooler reduces the evaporation rate of liquid helium or cools a superconducting magnet in a cryogen-free cryostat.

Abstract: An apparatus to detect gamma rays, comprising a scintillator, a position sensitive photo sensor and a scintillation-light-incidence-angle-constraining, SLIAC, element, the scintillator has faces and the position sensitive photo sensor detects scintillation photons exiting a scintillation photons transparent face of the scintillator, and a portion of a scintillator face is covered with an absorbing layer, which absorbs scintillation photons created by scintillation events due to the interaction of incoming gamma rays with the scintillator, and the SLIAC element is optically coupled between a scintillation photons transparent face of the scintillator and the position sensitive photo sensor and the SLIAC element guides the scintillation photons exiting the scintillator towards the position sensitive photo sensor, and the SLIAC element restricts the maximum allowed half light acceptance angle for the scintillation light hitting the position sensitive photo sensor to less than 45°.

Abstract: A transport device for transporting an NMR sample to the probe head (16) of an NMR spectrometer by means of a transport system (12) is characterized in that the transport device comprises a shuttle (15) adapted for use with a transport system. The transport system is structured to transport an HR-NMR sample spinner or an NMR MAS rotor (5). The shuttle includes a locking device for the NMR MAS rotor, the locking device being formed such that the NMR MAS rotor is released by unlocking the locking device and can be transferred to and received by the NMR MAS probe head. It is therefore possible to rapidly change from NMR spectroscopy of liquids to NMR spectroscopy of solids, and vice versa, simply by exchanging the probe head, without converting the transport system.

Abstract: A method for homogenizing the static magnetic field with a distribution B0(r) in the active volume of a magnetic resonance apparatus having a number N of shim coils defines a target field distribution B0T(r) using a filter method in which a norm of the shim currents is influenced by means of filter factors. An optimization procedure works in a parameter space having M control parameters, wherein 2?M<N. One of the control parameters is used as a weighting parameter for modification of a spatial weighting function and another control parameter is used to control the filter factors. Using this method the hardware limitations can be taken into account when determining the target field distribution, without a significant increase in the computational effort to determine the target field distribution during optimization.

Abstract: A gradient coil system has a cylindrical section in a central region, which contains no conductor elements and has a maximum outer radius that is larger than a minimum inner radius of conductor elements of a main gradient coil. An outer radius of this cylindrical section is only insubstantially smaller or equal in size to a minimum inner radius of a shielding coil in this axial range. The free space in the center of the gradient coil system is used to insert a passive RF shield, whose radius in a central region becomes larger over a certain length than its radius in outer regions. The RF shield is constructed from at least three partial sections, which are electrically interconnected. The actively shielded gradient coil system maximizes the volume of the RF region without loss of gradient coil system performance.

Abstract: A method for indicating the level of a liquefied gas in a cryogenic tank having a resistance temperature detector (1). The controller applies a heating pulse to the detector and performs a single resistance measurement after the heating pulse. The overheating of the sensor and the time interval for the measurement are found in a separate set of test experiment. As a result, for temperature sensors with negative temperature coefficient, the resistance of the sensor in gas is below some unique characteristic value, which can be used like a threshold criterion to distinguish between the liquid and the gas in a wide temperature range. For sensors with positive temperature coefficient, the resistance of the sensor in gas is larger than some unique characteristic value, which can be used like a threshold criterion to distinguish between the liquid and the gas in a wide temperature range.

Abstract: An NMR apparatus includes a superconducting magnet coil system configured to generate a homogeneous magnetic field, and a helium (He) tank having an inner tube mechanically rigidly connected to the He tank and in which the magnet coil system is positioned. The He tank is configured to contain liquid helium to cool the magnet coils. A radiation shield has a radiation shield inner tube encompassing the He tank and spaced from the He inner tube to create a space between the He inner tube and the radiation shield inner tube to reduce an evaporation rate of the liquid helium. The NMR apparatus additionally includes a field shaping device with a magnetic material arranged in the space, in order to shim the homogeneous magnetic field. The field shaping device is fixed in the space so as to be in rigid mechanical contact with the He tank but without contacting the radiation shield.