An NMR magnet system uses a Stirling cooler having a cold head that extends into a housing of the system to cool a cold shield surrounding a cryogen vessel. The system may have a damper located between the cooler and the cold shield to reduce a transmission of vibration from the cooler to a magnet coil immersed in the cryogen. The damper may be passive, or may be part of an active damping system that uses an acceleration sensor to drive an active damper that compensates for cooler vibration. A compensation apparatus may use a stored characteristic of a signal distortion caused by the vibration and, in response to a trigger signal from the cooler, apply compensation to an excitation signal provided to a sample by an NMR probe in a bore of the magnet coil, or to an FID signal from the sample that is detected by the probe.

An NMR magnet system uses a Stirling cooler having a cold head that extends into a housing of the system to cool a cold shield surrounding a cryogen vessel. The system may have a damper located between the cooler and the cold shield to reduce a transmission of vibration from the cooler to a magnet coil immersed in the cryogen. The damper may be passive, or may be part of an active damping system that uses an acceleration sensor to drive an active damper that compensates for cooler vibration. A compensation apparatus may use a stored characteristic of a signal distortion caused by the vibration and, in response to a trigger signal from the cooler, apply compensation to an excitation signal provided to a sample by an NMR probe in a bore of the magnet coil, or to an FID signal from the sample that is detected by the probe.

A nuclear magnetic resonance (NMR) system-based substance measurement method, including: acquiring several echo signals of an NMR pulse sequence varying in echo spacing from a substance to be measured followed by processing to obtain several signals varying in transverse relaxation and diffusion attenuation; and fitting, in combination with the prior knowledge, the signals to obtain the diffusion coefficient, transverse relaxation time or/and content weight of individual components of the substance to be measured. This application further provides a substance measurement system including a console, a magnet module, and an NMR system.

A subject S to which .sup.17O gas has been administered is placed within a fixed uniform static magnetic field of an NMR apparatus 1. The subject is irradiated, through proton coupling, with an excitation pulse produced using a pulse sequence having a short cycle time of 20.4 msec or less, preferably 10.4 msec or less, and more preferably 5.6 msec or less. An NMR signal generated due to .sup.17O nuclei of .sup.17O water produced within the subject by oxygen metabolism of the .sup.17O gas being excited by irradiation with the excitation pulse is detected with high sensitivity and is processed in accordance with a prescribed imaging sequence in which an MRS sequence is used.

A process for producing liquid transportation fuels in a petroleum refinery while preventing or minimizing corrosion of refinery process equipment. Spectral data selected from mid-infrared spectrometry, nuclear magnetic resonance spectrometry, or both is obtained and converted to wavelets coefficients data. A pattern recognition genetic algorithm is then trained to recognize subtle features in the wavelet coefficients data to allow classification of crude samples into one of two groups based on corrosion propensity. One of several actions is taken depending upon the measured corrosion propensity of the potential feed stock in order to prevent or minimize corrosion while producing one or more liquid hydrocarbon fuels.

A computer-implemented method of processing .sup.1H-NMR spectral data is disclosed. The method comprises receiving .sup.1H-NMR spectral data for a sample or set of samples, performing a Fourier transform of the .sup.1H-NMR spectral data to obtain Fourier-transformed spectral data, first differentiating the imaginary part of the Fourier-transformed spectral data or processed Fourier-transformed spectral data obtained from the Fourier-transformed spectral data to obtain a first derivative and storing the first derivative in storage.

A method for acquiring nuclear magnetic resonance (NMR) phase-sensitive two-dimensional (2D) J-resolved spectrum by suppressing strong coupling spurious peaks, comprising: 1) placing a sample, collecting a conventional one-dimensional (1D) spectrum of the sample, and measuring a time width (pw) of a 90° pulse, wherein the conventional 1D spectrum provides J coupling information and chemical shift information of the sample; and 2) introducing a pulse sequence for suppressing strong coupling, setting parameters of a chirp sweep frequency pulse, a pure shift yielded by chirp excitation (PSYCHE) module, and a J sampling module, and collecting and saving data of a spectrum.

A method for preparing an NMR material, comprising generating parahydrogen in gas or liquid form at a first location; transporting the parahydrogen away from the first location; mixing a precursor compound including a metabolite component with a catalyst for hydrogenation; hydrogenating the precursor compound using the parahydrogen; transferring polarization in the precursor compound to a nuclear spin of the metabolite component; cleaving a side arm of the precursor compound in a chemical reaction, with the metabolite molecule being one of the products of the reaction; separating the metabolite molecule from the catalyst for hydrogenation and other products of the reaction; and generating metabolite molecules for use in an MRI scanner by extracting a sample of the metabolite molecule having at least 5% polarization.

In one aspect, the disclosure relates to a compact membrane reactor for parahydrogen induced hyperpolarization, the reactor including an inner tube constructed of a semipermeable membrane, an outer tube surrounding the inner tube, and a means for controlling the magnetic field surrounding the outer tube. In some aspects, multiple compact membrane reactors can be arranged in parallel. In other aspects, the compact membrane reactor is equipped with a mechanism for magnetic field control. Also disclosed are fluid handling systems and sample preparation systems comprising the compact membrane reactors disclosed herein. The compact membrane reactor can be operated in a batch mode, a stopped-flow mode, or a continuous flow mode and can be configured to work with existing NMR spectrometers and MRI instruments.

In one aspect, the disclosure relates to a compact membrane reactor for parahydrogen induced hyperpolarization, the reactor including an inner tube constructed of a semipermeable membrane, an outer tube surrounding the inner tube, and a means for controlling the magnetic field surrounding the outer tube. In some aspects, multiple compact membrane reactors can be arranged in parallel. In other aspects, the compact membrane reactor is equipped with a mechanism for magnetic field control. Also disclosed are fluid handling systems and sample preparation systems comprising the compact membrane reactors disclosed herein. The compact membrane reactor can be operated in a batch mode, a stopped-flow mode, or a continuous flow mode and can be configured to work with existing NMR spectrometers and MRI instruments.