The longitudinal relaxation times (T.sub.1) of water and hydrocarbon inside porous media, such as rock from subsurface formations, behave differently when external magnetic fields vary. A Nuclear Magnetic Relaxation Dispersion (NMRD) profile from Fast Field Cycling Nuclear Magnetic Resonance (FFC-NMR) technique differentiates the type of fluids filling the pores. Different types of pores in a rock sample are filled with different fluids, water and hydrocarbon, and the absolute porosity and the pore size of each type of pores is determined.

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 .sub.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.

Nuclear magnetic resonance (NMR) methods and apparatus are provided for investigating a sample utilizing NMR pulse sequences having solid state and CPMG pulse sequence portions. Various embodiments of solid state pulse sequences may be utilized including two-dimensional (repetitive) line-narrowing sequences. The hydrogen content of a solid portion of the sample may be determined by using one or more echoes resulting from the solid state sequence portion of the pulse sequence to establish a total organic hydrogen content of the sample, and by using a CPMG echo train to establish a fluid organic hydrogen content, and by subtracting one from the other to obtain the hydrogen content of the sample's solid portion. Additionally, or alternatively, the T.sub.2 values obtained from the line-narrowing and CPMG pulse sequences can be compared by plotting to obtain information regarding a characteristic of the sample. The NMR pulse sequence may also include a T.sub.1 portion.

Nuclear magnetic resonance (NMR) methods and apparatus are provided for investigating a sample utilizing NMR pulse sequences. In various embodiments, the NMR pulse sequences have a solid state portion and a line-narrowing portion. In other embodiments, the NMR pulse sequences have a first line-narrowing portion and a second line-narrowing portion where the sequences of the different portions are different. In yet other embodiments, the NMR pulse sequences have a T.sub.1 portion and a line-narrowing portion. Processing of detected signals permits determination of characteristics of the sample including, in some cases, a differentiation of multiple components of the sample.

The longitudinal relaxation times (T.sub.1) of water and hydrocarbon inside porous media, such as rock from subsurface formations, behave differently when external magnetic fields vary. A Nuclear Magnetic Relaxation Dispersion (NMRD) profile from Fast Field Cycling Nuclear Magnetic Resonance (FFC-NMR) technique differentiates the type of fluids filling the pores. Different types of pores in a rock sample are filled with different fluids, water and hydrocarbon, and the absolute porosity and the pore size of each type of pores is determined.

A whole measurement process includes a plurality of step combinations. Each of the step combinations is composed of a solution-state measurement step and a solid-state measurement step. In the solution-state measurement step, solution-state NMR measurement is performed such that magnetization that is to be used in the solid-state measurement step remains. In the solid-state measurement step, solid-state NMR measurement is performed by using the magnetization that remains. No waiting time for recovering magnetization is provided between the solution-state measurement step and the solid-state measurement step. The solid-state measurement step may be performed earlier, and the solution-state measurement step may be performed later. Alternatively, the two steps may be performed simultaneously.

A method for the magnetic resonance examination of a measurement object is described, in which a measurement sequence is used in which the magnetic resonance response to the transmitted signal during transmission is measured. It is provided that a correction signal corresponding to the transmitted signal be generated and be used for correction of the response signal. To this end, the correction signal is modulated by a phase value and an amplitude value. The phase value and the amplitude value are automatically and iteratively customized for optimum correction of the response signal by an optimization method using a respective present state value of the measurement signal. Further, a radio-frequency unit (1) is described that can be used to carry out the method according to the invention.

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 .sub.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 a support frame with 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.

Disclosed are methods of characterizing kerogen and its hydrocarbon generation potential using NMR as the primary analytical tool, and using such data to derive the kinetics of hydrocarbon generation and alteration, thus predicting the hydrocarbon potential of source rock in geological setting, which can then be used in petroleum exploration and production.

A method and system enabling a determination of the risk of developing breast cancer of a subject, comprises using a magnetic resonance spectroscopy device to obtain the level of the spectral signal at 3.15 and 3.19 ppm, within the breast tissue of the subject, and comparing the level of the spectral signal obtained in the first step with a reference level of a spectral signal at 3.15 and 3.19 ppm of the breast of a healthy subject, to determine whether the level of the signal obtained in the first step exceeds the reference level of a healthy subject is comparable to that of a subject known to be at elevated risk; or is elevated to the level of persons known to be carrying a gene mutation.