33 results about "Nmr magnet" patented technology

An NMR apparatus comprising an NMR magnet system disposed in a first cryocontainer (2) of a cryostat (9), and an NMR probe head (1), wherein the first cryocontainer (2) is installed in an evacuated outer jacket and is surrounded by a radiation shield (24) and / or a further cryocontainer (3), wherein a cooling device is provided for cooling the NMR probe head (1) and a cryocontainer (2, 3), which comprises a cold head (4, 4a, 4b, 4c) with several cold stages (12a, 12b, 12c, 18a, 18b, 18c, 19a), wherein one cold stage (12a, 12b, 12c, 18a, 18b, 18c, 19a) is connected to a heat-transferring device, and wherein a cooling circuit is provided between the cooling device and the NMR probe head (1), is characterized in that the cooling device is disposed in a separate, evacuated housing (6) which is positioned directly above the cryostat (9), wherein the heat-transferring device is inserted directly into suspension tubes (29a, 29c) of the cryocontainer (2, 3) and / or is in contact with the radiation shield (24). This effects a simple construction that is efficient for cooling an NMR apparatus.

An NMR spectrometer comprising an NMR magnet system (27) disposed in a helium tank of a cryostat and an NMR probe head (11) disposed in a room temperature bore of the cryostat, which contains a cooled RF resonator (9) for receiving NMR signals from a sample to be investigated, and a cooled pre-amplifier (10), wherein the NMR probe head (11) is cooled by a common multi-stage compressor-operated refrigerator (2), wherein the refrigerator (2) comprises a cold head and several heat exchangers (5, 6) at different temperature levels, wherein the refrigerator (2) is disposed at a spatial separation from the cryostat in a separate, evacuated and thermally insulated housing (1) and wherein at least one cooling circuit with cooling lines, which are thermally insulated by a transfer line (13, 14) is disposed between the housing (1) containing the heat exchangers (5, 6) and the NMR probe head (11), is characterized in that additional cooling lines to an LN2 tank (18) or radiation shield (21) disposed in the cryostat and surrounding the helium tank are provided, and the refrigerator (2) also cools the LN2 tank (18) or the radiation shield (21). The inventive NMR spectrometer comprises a simple and inexpensive device for matching the holding time of LN2 to that of LHe through cooling the LN2 tank using the refrigerator provided for cooling the NMR probe head and without great expense.

An apparatus and method for providing RF shielding for performing nuclear magnetic resonance ("NMR") procedures, comprising a radio-opaque holder in combination with radio-opaque magnet components to form an RF shield around a patient undergoing an NMR procedure. In embodiments, a radio-opaque holder having a radio-opaque bottom portion and a radio-opaque canopy is adjoined to an NMR magnet having a radio-opaque cryostat and a radio-opaque service end cap to form an RF shield. A patient is placed on a patient support unit located in the holder bottom portion. The patient support unit, including the patient, is then inserted into the cavity of the NMR magnet and a canopy is placed on top of the bottom portion of the holder. An RF shield is thus created comprising the canopy, the bottom portion, the cryostat of the magnet, and an end cap on the service end of the magnet.

A split type magnet device configured for a high-sensitivity NMR apparatus and used for solution analysis generates a uniform magnetic field at the center portion of the magnet device of at least 11 T, which is used for determining a sample. The NMR magnet device has left and right solenoid superconducting magnets, which face each other with a predetermined distance being provided therebetween. The left solenoid superconducting magnets and the right solenoid superconducting magnets are substantially coaxial to a central axis, and constituted respectively by a plurality of outermost magnets and a separate plurality of innermost magnets. When a sample energizing current generates a main magnetic NMR detection field in the vicinity of a center portion of the apparatus the current direction in at least one of the plurality of innermost magnets is minus while the current direction in at least one of the plurality of outermost magnets is plus.

The invention concerns a method for charging an actively shielded magnet coil arrangement (20) comprising a first partial region (21) which can be superconductingly short-circuited using an additional switch (23), and a second partial region (22), wherein the two partial regions (21, 22) generate dipole moments of different signs. The magnetic fringe field B* is measured close to the desired operating state of the arrangement (20) and operating currents are determined for each of the two partial regions (21, 22) at which the overall magnetic field B is free from an additional dipole moment caused by production tolerances to permit setting of the theoretically optimum fringe field, irrespective of production tolerances. These operating currents are adjusted taking into consideration the inductive coupling between the partial regions (21, 22) through initially charging the entire magnet coil arrangement (20) and, after closing the additional switch (23), through continuation of the charging process in the second partial region (22) only. This eliminates deviations, which are caused by production tolerances, from the optimum theoretical fringe field of the arrangement (20) in a simple and inexpensive manner.

The invention concerns a method for charging a magnet arrangement (20) comprising a first partial region (21) which can be superconductingly short-circuited via an additional switch (23), and a second partial region (22), wherein the two partial regions (21, 22) generate, in an investigational volume (8), gradients of second order having different signs. A magnetic field dependence B* is measured close to the desired operating state of the magnet arrangement (20) and operating currents are determined for each of the two partial regions (21, 22) at which the overall magnetic field B in the volume (8) under investigation is freed from a magnetic field gradient of second order. These operating currents are set thereby taking into consideration the inductive coupling of the partial regions (21, 22) through initially charging of the overall magnet arrangement (20) and, after closing of the additional switch (23), through continuation of charging only in the second partial region (22). The magnetic field homogeneity of the magnet arrangement (20) can thereby be improved in a simple and inexpensive manner.

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.

A method for testing a new superconducting wire involves charging an actively shielded magnet coil configuration which comprises a first partial region which can be superconductingly short-circuited using an additional switch. A superconductor to be tested under increased current load is used in this first partial region, thereby preventing superconductor in the second partial region from being subjected to this increased current load. Operating currents are determined for both partial regions that have the desired excess current in the first partial region, with the overall field B0 only slightly differing from the standard operating field of the magnet coil configuration. The operating currents are adjusted through initial charging of the overall magnet coil configuration, thereby taking into consideration the inductive coupling between the partial regions and after closing of the additional switch, by continued charging or discharging in the second partial region only. The method permits inexpensive testing of a superconductor in a series-produced NMR magnet under NMR conditions.

A capillary cartridge assembly for positioning a sample fluid at a geometric center between juxtaposed pole pieces of a NMR magnet assembly for NMR analysis comprises a capillary captured in a channel in a printed circuit board assembly that is sized to fit between the pole pieces. The assembly includes a RF coil surrounding a portion of the capillary. Electric traces shaped to function as shim coils can be included in the printed circuit board. An end of the printed circuit board includes electrically conductive contacts that plug into a receptacle to connect the RF coil and traces to external electrical circuitry when the RF coil is in the geometric center. The capillary can be a continuous flow-through capillary or a closed cartridge.

An NMR spectrometer (131) with an NMR magnet coil (91) having windings of a conductor with a superconducting structure (1), which have a plurality of band-segments (2, 2a, 7a-7e, 8a-8d, 15) made of band-shaped superconductor. Each band-segment (2, 2a, 7a-7e, 8a-8d, 15) has a flexible substrate (3) and a superconducting layer (4) deposited thereon, wherein the band-segments (2, 2a, 7a-7e, 8a-8d, 15) each have a length of 20 m or more. At least one of the band-segments (2, 2a, 7a-7e, 8a-8d, 15) forms a linked band-segment (2, 2a), and each linked band-segment (2, 2a) is connected to at least two further band-segments (7a-7e) in such a way that the combined further band-segments (7a-7e) overlap with at least 95% of the total length (L) of the linked band-segment (2, 2a). The magnet coil generates particularly high magnetic fields in a sample volume and has a low drift.

Methods for improved interpretation of NMR data acquired from industrial samples by simultaneously detecting more than one resonant nucleus without removing the sample from the sensitive volume of the NMR magnet or radio frequency probe are disclosed. In other aspects, the present disclosure provides methods for robust imaging / analysis of spatial distribution of different fluids (e.g., 1H, 23Na, 19F) within a core or reservoir rock. NMR data may be interpreted in real-time during dynamic processes to enable rapid screening, e.g. of enhanced oil recovery techniques and products and / or to provide improved interpretation of well-logs. Measurements of resonant nuclei other than 1H may be performed in the laboratory or downhole with a NMR logging tool. In other aspects, the present disclosure describes a novel kernel function to extract values for underlying parameters that define relaxation time behavior of a quadrupolar nucleus.

The invention discloses a high-field in-situ polarization device using parahydrogen-induced polarization. The outlet end of the reaction gas inlet channel is connected to one end of a third through valve, and the other end of the third through valve is respectively connected to the parahydrogen inlet channel. The outlet end of the fourth through valve is connected to one end of the fifth through valve, the other end of the fifth through valve is connected to the inlet end of the third one-way valve, and the outlet end of the third one-way valve is connected to one end of the eighth through valve and one end of the eighth through valve respectively. One end of the sixth straight-through valve is connected, the other end of the eighth straight-through valve is connected to the reaction sampling pipe, the other end of the sixth straight-through valve is connected to the vacuum pump through the vacuum chamber, the seventh straight-through valve, and the vacuum gauge in sequence, and the eighth straight-through valve is connected to the third one-way valve. A third pressure gauge is arranged at one end connected to the outlet of the valve, and the reaction sampling tube is placed in the nuclear magnetic resonance magnet. The invention also discloses a high-field in-situ polarization method utilizing parahydrogen-induced polarization. The invention has the advantages of simple structure, convenient control and operation, and realizes efficient polarization generation and stable polarization nuclear magnetic spectrum signal collection.

A transfer device is provided for shuttling an NMR sample container between at least two coaxially arranged NMR magnet systems of an NMR spectrometer comprising a guide tube positioned in a central bore of the magnet systems, a shuttle assembly arranged inside the guide tube for securely holding and shuttling the sample container and a drive system comprising a pulling drive and a winch cord attached to the drive system on one side and to the shuttle assembly on the other side, such that the shuttle assembly can travel inside the guide tube. The transfer device has a pneumatic pressurizing arrangement with an entry for pressurized gas arranged on a gas-tight body above the shuttle assembly that is adapted to maintain the winch cord under tension. The shuttle assembly comprises a piston design being moveable along the common axis of the coaxial magnet systems under the influence of the pressure.

The invention relates to a temperature regulating system for an NMR magnet system. The device comprises a permanent magnet arrangement (1) having a central air gap (2) for generating a uniform static magnetic field in a measurement volume inside the central air gap (2), an NMR sample head (3) for emitting HF pulses and receiving HF signals from a measurement sample (0), comprising frequency detection in the NMR sample head and HO coils for varying the amplitude of the static magnetic field, and a shimming system (4) in the central air gap for further homogenizing the magnetic field in the measurement volume, in which a first isolation chamber (5) surrounds the permanent magnet arrangement in a thermally shielded manner, the first isolation chamber comprises means (6) for adjusting the temperature T1 of the first isolation chamber, the shimming system, the HO coil and the NMR sample head are arranged in the central air gap outside the first isolation chamber, and at least one heat conductor (7) is arranged between the shimming system and the HO coil on the one hand and the permanent magnet arrangement on the other hand. Therefore, the field stability and the drifting-free property of the arrangement structure are obviously improved.

The invention provides a high-magnetic-field-strength and high-uniformity nuclear magnetic resonance magnet structure and a measuring device. The magnet structure comprises a housing and at least twomagnet layers which are arranged in the housing, wherein at least two magnet layers are vertically stacked in the housing. The magnetization directions of at least two magnet layers are same. According to the invention, through vertically stacking two or more magnet layers with the same magnetization directions in the housing, the nuclear magnetic resonance magnet structure is formed. The magneticfields which are generated by two or more magnet layers are stacked, thereby generating a static magnetic field together. Compared with a static magnetic field which is generated by a single layer ofmagnet, the static magnetic according to the invention has advantages of improving magnetic field uniformity and magnetic field strength, and increasing the area of a uniform area and detecting distance. Through cooperative use of a specific RF antenna and the magnet structure, layered heterogeneous samples and homogeneous samples can be effectively measured, thereby expanding application range of a nuclear magnetic resonance measurement device.