Abstract: A method for nuclear magnetic resonance (NMR) or magnetic resonance imaging (MRI) measurements, includes creation of enhanced polarization of nuclei of a first kind within a sample in a magnetic field at cryogenic temperatures and transfer of the polarised sample to room temperature. The enhanced polarization of nuclei of the first kind is thereby transformed into long-lived states (LLS) of nuclei of a second kind and these LLS are sustained. The LLS is at least partially converted into observable magnetisation and an NMR or MRI measurement is carried out. The method allows one to extend the time needed between hyperpolarised magnetisation and NMR detection.

Abstract: A method for nuclear magnetic resonance (NMR) spectroscopy of a sample comprises preparation of the sample and carrying out an NMR spectroscopy measurement. Preparation includes excitation of long lived coherences (LLC) between the singlet state S0 and the central triplet state T0 of nuclei of the sample. The thermal equilibrium Boltzmann distribution (Iz+Sz) is thereby transformed into a difference (Iz?Sz), which is flipped to the transverse plane, and irradiation of the sample with an rf-field is initiated. The LLC is sustained by maintaining the rf-irradiation during an interval t1 and the LLC is converted into observable magnetisation by interrupting the rf-irradiation. The method allows nuclear magnetic resonance spectroscopy measurements with improved spectral resolution.

Abstract: A superconducting magnetic field coil (1; 21; 31; 41; 51; 61) comprising at least one coil section (42; 43) which is wound in layers, is characterized in that, in at least one layer (11, 12, 13, 14, 101, 102, 103, 104) of the coil section (42; 43) N (with N?2), superconducting wire sections (A, B, C, D, E) are wound in parallel, such that the windings of the N wire sections (A, B, C, D, E) are adjacent to each other and the N wire sections (A, B, C, D, E) are connected in series. The inventive magnetic field coil can be produced at highly reduced costs, in particular, when the magnetic field coil has a comparatively large layer length.

Abstract: A method for determining the spatial distribution of magnetic resonance (MR) signals from an imaging region has a preparatory step in which an encoding scheme with I phase encoding steps is defined, for each phase encoding step according to the phase encoding scheme, an excitation pattern of the transverse magnetization is defined and RF pulses to be irradiated to implement this pattern are calculated, wherein the same phase is defined at all spatial locations of the imaging region within an MSEM region and, in the execution step, according to the spatial encoding scheme each encoding step is performed I times according to the phase encoding scheme, wherein selection of the imaging region, amplitude modulation, and phase encoding are performed with the calculated RF pulses during excitation of the nuclear spin. This results in unique determination of the spatial distribution of the magnetic resonance signals with a simple RF receiver configuration using local gradient systems.

Abstract: A superconducting magnet system with a superconducting magnet coil system, which is disposed in a cryogenic fluid tank (2) of a cryostat (1), and an exchangeable refrigerator (5; 31) which is operated in a vacuum container (8) and is provided to re-liquefy the cryogenic fluid flowing through a tubular conduit (4; 21) is characterized in that the tubular conduit (4; 21) is rigidly installed in the cryostat (1). The refrigerator reaches its optimum performance during operation in a vacuum, and can be easily exchanged in case of a defect.

Abstract: A method and an apparatus serve the purpose of determining the fat or oil content of a sample. The sample is dried under the action of a microwave field and is examined under the action of a radio-frequency signal and of a constant magnetic field by means of nuclear magnetic resonance. The sample is exposed to the microwave field, the radio-frequency signal and the magnetic field at the same measuring place in a common measuring chamber. The apparatus has a microwave source for drying the sample, a magnetic system for generating a nuclear magnetic resonance magnetic field in the sample, and a nuclear magnetic resonance measuring arrangement for irradiating radio-frequency signals into the sample and for receiving excited nuclear magnetic resonance signals from the sample. The microwave source, the magnetic system and the nuclear magnetic resonance measuring arrangement are connected to a common measuring chamber in which the sample is located.

Abstract: A method for generating MR (magnetic resonance) images of a moving partial area of an object with a repeating motion sequence over comparable motion states, wherein an MR data set, which is encoded for generating an individual MR image of the object, is provided for each motion state from a plurality of successive individual MR measurements with shorter time intervals than a repetition rate of the motion sequence, and wherein at least one navigator data point is generated for each individual MR measurement as an indicator for the comparability of several motion states, is characterized in that a position of the partial area is determined for each individual MR image, from which a function f(t) of the time shift of the position is determined, and the measuring data of the individual MR measurement is phase-corrected in correspondence with its respective motion state using the function f(t) to keep the position of the partial area in a spatially stationary state.

Abstract: A device that comprises an RF generator (29), an NMR transmission (20) and reception system (21) and a first control loop (28), with which the frequency fRF of the RF generator is synchronized with the resonance frequency f0 of an NMR line, wherein, from the signal of the RF generator, a train of excitation pulses (EX) of the repetition frequency fm is generated, with which nuclear spins of a certain resonance frequency of an associated NMR line are excited quasi-continuously (CW) and, in the times between the excitation pulses, the NMR signal is received (AQ), wherein the period time 1/fm is chosen to be much smaller than the relaxation time of the NMR line, preferably shorter than 1/10 of the relaxation time, and the NMR signal UD mixed down into the low-frequency range is used, with the help of the first control loop, to closed-loop-control the value of the transmission frequency (=frequency lock) or the value of the B0 field (=field lock) in such a way that the frequency and phase of the RF generator and

Abstract: A method for producing a Sn based alloy (15) comprising a metal matrix of a metal matrix material, wherein the metal matrix material comprises Sn, and inclusions of a compound material, further referred to as compound inclusions, wherein the compound material contains one element or a combination of elements of the group Ti, V, Zr, Hf, further referred to as dopant, and one or a plurality of other elements, in particular Sn, Cu and/or Nb. Particles of the metal matrix material, further referred to as matrix particles, are mixed with particles of the compound material, further referred to as compound particles, and the matrix particles and the compound particles are compacted during and/or after their mixing. A Sn based alloy containing finer compound inclusion of a dopant can be prepared, in order to produce Nb3Sn superconductor material with a superior current carrying capacity.

Abstract: A method for obtaining amplitude and phase dependencies of radio frequency pulses, which are irradiated within the scope of a main magnetic resonance experiment for generating a predetermined n-dimensional spatial distribution (n>=1) of transverse magnetization in an object by means of at least one radio frequency transmitting antenna of a magnetic resonance measuring system in combination with spatially and temporally varying additional magnetic fields which are superimposed on the static and homogeneous base field of the magnetic resonance measuring system and change the transverse magnetization phase in the object in dependence on location and time is characterized in that, prior to performance of the main experiment, a preparational measurement is performed in which the change with time of the transverse magnetization phase in the object under the action of the additional magnetic fields is measured in a position-resolved fashion and the amplitude and phase dependencies of the radio frequency pulses fo

Abstract: A method for magnetic resonance spectroscopy (=MRS) or magnetic resonance imaging (=MRI) in which an NMR time-domain signal is created by an RF excitation pulse applied to an object in the presence of an applied magnetic field that may depend on spatial position and/or time, the time-domain signal being generated by an excited transverse nuclear magnetisation precessing about the applied magnetic field, whereby the RF excitation pulse is adapted to cover a whole range of NMR frequencies of interest present in the object, and time-domain signal acquisition takes place during, or during and after the application of the RF excitation pulse, is characterized in that spectral or image data are reconstructed by a matrix product of a reconstruction matrix and a vector of time-domain signal points, the reconstruction matrix being an inversion of an encoding matrix An? whose elements are calculated using the formula: A n ? ? ? = ? m = 0 n - 1 ? ? P m ? ? ?? ? ( n , m , ? ) , whe

Abstract: A device for monitoring a living object during a magnetic resonance (MRI) experiment in an MRI tomograph, wherein the device comprises one or more individual electrodes which are connected in an electrically conducting fashion to the living object to be examined, and are connected to a monitoring device via signal lines, wherein each signal line comprises individual parts that are electrically connected to each other via impedances. The eigenfrequencies of these parts are higher than the NMR measuring frequency, preferably more than twice as high, and the parts are electrically connected to each other via frequency-dependent impedances Zn. The electro-magnetic coupling from the RF antenna and the gradient coils to the signal lines can thereby also be minimized in a simple fashion.

Abstract: A cryostat configuration has a magnet coil system (2) disposed in a helium tank (1), and a horizontal room temperature bore (3) which provides access to a volume under investigation in the center of the magnet coil system (2). The helium tank (1) contains undercooled liquid helium at a temperature of less than 3.5 K, in particular of approximately 2 K, and the cryostat configuration has at least one vertical tower structure (4) on its upper side for filling in and evaporating helium. The tower structure (4) contains a container (5) with liquid helium of 4.2 K which is separated from the helium tank (1) by a thermal barrier (7), and the helium tank (1) contains an undercooling unit (9). This yields a compact cryostat configuration which achieves continuous, stable long-term operation with an undercooled high-field magnet coil.

Abstract: A method for determining the spatial distribution of the magnitude of the radio frequency transmission field B1 in a magnetic resonance imaging apparatus, wherein the method comprises performing an MRI experiment in which a B1-sensitive complex image (SI) of a sample is obtained, wherein the phase distribution within the B1-sensitive complex image (SI) depends on the spatial distribution of the magnitude of the field B1. For establishing the dependency of the phase distribution within the B1-sensitive complex image (SI) on the spatial distribution of the field B1, one or more adiabatic RF pulses are applied. The method provides a simple procedure for mapping the B1 field of a magnetic resonance imaging apparatus with an improved accuracy and a wider measurement range.

Abstract: A nuclear magnetic resonance (NMR) resonator (1; 31) comprising an inductive section (6) and a capacitive section (6a), wherein the inductive section (6) is band-shaped and surrounds a substantially cylindrical volume under investigation (5), wherein the capacitive section (6a) is formed from one or more discrete capacitor(s) (13; 13a, 13b, 13c, 13d), and wherein the ends (7, 8) of the band-shaped inductive section (6) are connected through one or several capacitor(s) (13; 13a, 13b, 13c, 13d) of the capacitive section (6a), is characterized in that the inductive section (6) is formed from a dielectric flexible foil (2) which is conductively coated on both sides and the ends (7, 8) of the band-shaped inductive section (6) overlap, wherein the outer coating (4) of the inner end (7) is electrically conductingly connected to the inner coating (3) of the outer end (8), with one or more through-connections (10) being provided in the area of the inner end (7) of the band-shaped inductive section (6), and the outer c

Abstract: A magnetic field gradient generating system for a NMR system, includes at least one set of gradient coils, preferably arranged according to three axes of a spatial referential system, and a controlled power supplying unit for the gradient coils, the power supplying unit including, for each gradient coil, a converter/amplifier module, the modules being fed with pulse sequences of digital gradient data provided as word streams by an adapted gradient data generator according to a pulse program, each arrangement of a gradient coil and a converter/amplifier module forming a gradient channel. The power supplying unit also includes an automatic blanking system which scans the gradient data words sent to the [converter/amplifier] modules and, according to sensed values, selectively delivers blanking signals to be applied to the modules in order to disable the power stages of their respective amplifiers connected to the gradient coils, when no current is to be fed to the coils.

Abstract: A sample exchange device (1), in particular, for an NMR spectrometer, comprising a circumferential chain (22), sample receptacles (7) which are disposed on the chain (22) at equal distances and are connected to each other via webs (23), and a measuring or transfer position (9), wherein each sample receptacle (7) can be moved to the measuring or transfer position (9) by moving the chain (22), characterized in that a chain guidance is provided which guides the circumferential chain (22) along a meandering path. The inventive sample exchange device is particularly economic and does not impair the analysis of the samples.