摘要:
The invention concerns an NMR (nuclear magnetic resonance) high field magnet coil system comprising superconducting conductor structures for generating a homogeneous magnetic field B0 in a measuring volume (23) with several radially nested solenoidal coil sections (12, 13, 31), which is characterized in that the radially innermost coil section (31) is wound with a band-shaped superconductor with an aspect ratio (width to thickness) >3 on a coil support which axially projects, at least at one axial end, past the winding packet of the radially neighboring coil section (12) and the band-shaped superconductor is guided on this side tangentially towards the outside to a region of reduced magnetic field strength and terminates in at least one electrical connecting point (16). This permits use of a brittle band-shaped superconductor for the innermost coil system (31) which cannot be strongly bent at the upper edge.
摘要:
A superconducting very high field magnet coil with several solenoidal multi-layer coil sections which are wound in layers onto a hollow cylindrical support body (3) about a common central axis a, and which are electrically connected in series to carry a current in excess of 100 A is characterized in that the radially innermost coil section (1) comprises superconducting wire (2) which contains oxidic, high temperature superconductor (HTS) material, wherein the layers of the radially innermost coil section (1) are helically wound such that there is a free axial space between the walls, which is then sealed. The corresponding production method comprises the steps of helically winding a layer of superconducting HTS wire together with a filler wire onto the support body; removing the filler wire from the support body; repeating steps (a) and (b) until a desired number of layers of the coil section is obtained; thermally treating the winding packet for reacting the HTS material under a gaseous atmosphere containing O2 with optimized annealing parameters; and sealing the hollow spaces of the coil section. This permits production of an NMR-capable solenoid coil having only a few superconducting joints, of topologically simple construction that can carry a current of a few hundred amperes and which contains HTS material to produce magnetic fields in excess of 21 Tesla.
摘要:
The invention concerns a superconducting magnet configuration for a high resolution NMR spectrometer which is highly stable over time and having a cryostat (21) with a vertical room temperature bore (23). A transverse access (32) through the cryostat (21) to the room temperature bore (23) is provided for at an easily accessible height directly above the upper end of the superconducting magnet coil (25) to substantially simplify the introduction of a sample. In a system having two helium tanks (26, 27), it is advantageous to have the access (32) arranged between these helium tanks.
摘要:
A cryostat (1) with a magnet coil system including superconductors for the production of a magnet field B0 in a measuring volume (3) has a plurality of radially nested solenoid-shaped coil sections (4, 5, 6) which are electrically connected in series, at least one of which being an LTS section (5, 6) with a conventional low temperature superconductor (LTS) and at least one of which being an HTS section (4) including a high temperature superconductor (HTS), wherein the LTS section (5, 6) is located in a first helium tank (9) of the cryostat (1) along with liquid helium at a helium temperature TL
摘要:
A cryostat (1) with a magnet coil system including superconductors for the production of a magnet field Bo in a measuring volume (3) has a plurality of radially nested solenoid-shaped coil sections (4, 5, 6) which are electrically connected in series, at least one of which being an LTS section (5, 6) with a conventional low temperature superconductor (LTS) and at least one of which being an HTS section (4) including a high temperature superconductor (HTS), wherein the LTS section (5, 6) is located in a first helium tank (9) of the cryostat (1) along with liquid helium at a helium temperature TL
摘要:
In a superconducting magnet coil configuration, in particular for a high resolution analytical nuclear resonance (NMR) spectrometer, with a cryostat having extremely low heat losses (low loss), comprising at least one essentially cylindrical container (1) with a vertical cylinder axis (k), with a vertical cylindrical room temperature bore (3) and with at least one inner tank (4) for a cryogenic liquid in thermal contact with a superconducting magnet coil (2) enclosing the room temperature bore (3), for generating a vertically directed, extremely homogeneous and stable magnetic field of high field strength inside a measuring volume of the room temperature bore (3), the vertical axes (r) of the room temperature bore (3) and of the superconducting magnet coil (2) run parallel to and at a distance from the vertical cylinder axis (k) of at least one of the cylindrical cryostat containers (1). In this way, access to the room temperature bore (3) is considerably simplified.
摘要:
The system describes a means and a method for stabilizing the magnetic field generated in the measuring volume of a high-resolution magnetic resonance spectrometer having an actively shielded magnet coil (4) which is located in a cryostat (2) and which is superconductingly short-circuited. The system comprises a compensation coil (12) which is decoupled from the magnet coil (4), and is disposed on the shielding coil (4b) of the magnet coil (4).
摘要:
An X-ray analysis device makes use of a variable aperture for controlling the position and cross section of the X-ray beam. The variable aperture is configured to allow changes in the cross section and/or position of the beam by movement of one aperture component in one direction. In one embodiment, the aperture medium is a perforated disk that is rotated to expose different aperture holes to the beam. In another embodiment, the aperture medium is a perforated tape that is moved in a linear direction to expose different aperture holes to the beam. The tape may be wound about two axes to control its movement, or may be a continuous loop. A cassette may also be used to house the tape.
摘要:
A description is given of a method for determining the content of a first component of a sample, which first component provides a first NMR signal and has a first self-diffusion coefficient D1, the sample additionally containing at least one further component which provides a further NMR signal and has a larger self-diffusion coefficient D2, in particular for determining the fat content of a hydrous sample, with the aid of a low-resolution nuclear magnetic resonance (NMR) pulse spectrometer, the sample being excited by a radio-frequency (RF) excitation pulse and being exposed to a magnetic gradient field and to a sequence of further refocusing RF pulses for generating spin echo signals, the spin echo signals being detected and their amplitude values being determined, from which a value for the content of the first component of the sample is determined. The magnetic gradient field is not switched off during the sequence of further refocusing RF pulses.
摘要:
The invention concerns a means and a method for stabilizing a magnetic field generated by a superconductingly short-circuited main coil located in a cryostat in the measuring volume of a high-resolution magnetic resonance spectrometer, which comprises compensation coils which are dimensioned and positioned such that they, in their entirety, are suited to largely compensate for field drifts of the superconductingly short-circuited main coil in the measuring volume. The drift compensation coils consist of HTS material and are disposed radially outside of the main coil at a higher temperature level.