A probe unit (100) including a magnet (102, 103) generates a static magnetic B.sub.0 field in an examination region and a RF coil (105). An input-output module (201) includes a transmitter (203) which controls the RF coil (105) to excite resonance and cause echoes (210) and a receiver (204) which demodulates and digitizes the echoes (210). A data processing module (206) includes at least one processor programmed to calculate a T.sub.2 relaxation distribution plot from a digitized echo (210) train, calculate a first area under the fat peak on the T.sub.2 distribution plot, calculate a second area under a water peak on the T.sub.2 distribution plot, and normalize the first and second area to determine a fat-to-water ratio.

A downhole tool includes a cylindrical housing. A magnet and an antenna may be positioned within the housing. An excluder may be positioned around the housing, and a thickness of the excluder may vary around the housing.

A nuclear magnetic resonance (NMR) apparatus includes at least one magnet configured to induce a static magnetic field in a sample of material to be analyzed. At least one radio frequency antenna is configured to induce a radio frequency magnetic field in the sample of material to be analyzed. The sample chamber is disposed in a substantially longitudinally continuous sample holder separated into discrete sample chambers. Each sample chamber has an internal opening dimension such that substantially all of each sample is affected by surface contact phenomena with an internal wall of each sample chamber.

Apparatuses and methods are provided for concentrating the magnetization of nuclear spins within a body, in one apparatus, a body having an electron spin moments and nuclear spin moments may subject to a polarizing magnetic field and a gradient magnetic field, such that a space-varied distribution of magnetic resonant frequencies of respective electron spin moments in the body is induced. The body may then be subject to a time-varying magnetic field configured to induce a spatial gradient of the electron spin magnetization such that concentrations of nuclear spin magnetization are induced. The body may be configured to receive a biological sample such that a concentration of nuclear spin magnetization may diffuse into the biological sample. The apparatus may further include a sensor configured to detect nuclear spin magnetization within the biological sample.

A mobile measuring device, in particular a hand-held measuring device, comprises a housing, in which at least one sensor device, a control device for controlling the sensor device, an evaluation device for evaluating the measurement signals supplied by the sensor device as well as a device for supplying energy to the measuring device are provided. The sensor device comprises at least one nuclear spin resonance sensor which is provided at least for the detection and/or analysis and/or differentiation of a material characteristic of a workpiece, in particular in a workpiece.

A mobile measuring apparatus for nondestructively determining a material measurement value that relates to a material property of a workpiece comprises a housing in which at least a first sensor device and a second sensor device are located, a control device, an evaluating device, and a device for the supply of energy to the measuring apparatus. The first sensor device has a nuclear magnetic resonance sensor and the second sensor device has a sensor based on dielectric and/or resistive methods. Information about the material property of the workpiece, in particular moisture present in the workpiece, is obtained by evaluating a measurement signal provided by the first sensor device, which information is intended for the optimized control of the second sensor device and/or optimized evaluation of measurement signals provided by the second sensor device.

The present invention relates to a method of correcting inhomogeneity of the static magnetic field generated by the magnet of a Nuclear Magnetic Resonance imaging machine, wherein the magnet is flat and the magnetic field on one side of said magnet is corrected such that a volume is defined, which is bounded by a spherical cap surface, in which volume and along which surface the magnetic field is homogeneous, i.e. has field lines having equal parallel directions and equal intensities.

An apparatus for NMR properties of subsurface formations includes a magnet, a transmitter antenna and at least one of a receiver section of the transmit antenna or a separate receiver antenna having a length along the longitudinal dimension of the apparatus which is shorter than a length of the transmitter antenna along the longitudinal dimension. The apparatus includes circuitry for applying radio frequency current pulses to the entire transmitter antenna and for receiving signals by the at least one of the receiver section of the transmitter antenna and the separate receiver antenna.

Methodologies and mechanisms are provided for introducing one or more magnetizable particles introduced non-invasively into one or more body structures containing nervous tissue in a subject, directing, guiding, transporting, focusing and/or concentrating the one or more particles using at least one image-guidance component in proximity to the one or more body structures which can direct the one or more particles within the one or more body structures, and modulating, using at least one activation component, the one or more particles to modulate neuronal function in the one or more body structures of the subject.

An NMR sensor is configured to make NMR measurements of a fluid and includes a housing defining a chamber. A nonmagnetic cap is deployed in the chamber and divides the chamber into first and second regions. The cap is sized and shaped to define a fluid collector in the first region. A magnet assembly is deployed in the second region and is configured to generate a static magnetic field in the fluid collector. A radio frequency (RF) coil is interposed between the magnet assembly and the cap and is configured to generate an RF magnetic field in the fluid collector. Methods include using the sensor to make NMR measurements of multi-phase fluids such as drilling fluid.