80 results about "Spin–lattice relaxation" patented technology

The present invention pertains to an apparatus and method for conducting magnetic resonance measurements on fluids at high pressures and / or high temperatures. The apparatus can be used in conjunction with or as part of a downhole fluid sampling tool to perform NMR measurements on fluids withdrawn from petroleum reservoirs, or can also be used for laboratory measurements on live reservoir fluids. The apparatus can perform all of the measurements made by modern NMR logging tools, including multi-dimensional distribution functions of spin-spin (T2) and spin-lattice relaxation (T1) times and molecular diffusion coefficients. The spin densities of hydrogen and other NMR sensitive species can be computed from the distribution functions. The apparatus can also be used to predict the apparent conductivity of the fluids in the flowline from measurements of the quality factor (“Q”) of the NMR circuit. The apparent conductivity can be used to predict water cut or water salinity.

A non-invasive blood glucose measurement method using a magneto-resonance absorption method. A constant magnetic field is applied using a pair of permanent magnets, the magnetic field having a uniform strength. A triangular waveform low frequency modulation magnetic field is applied using a low frequency generator and a pair of low frequency coils, the low frequency modulation magnetic field having a uniform strength. A weak acoustic wave modulation magnetic field is applied using an acoustic wave generator and a pair of acoustic wave coils. Electromagnetic waves are applied to a detector in which a finger is positioned to produce a nuclear magneto-resonance, the electromagnetic waves having a frequency varying in a specific frequency band step by step, the applying being done using a high frequency generator and a sensor coil. A magneto-resonance absorption signal produced by spin-lattice relaxation of protons in a tissue of the finger because of the nuclear magneto-resonance is detected. A magneto-resonance spin-lattice relaxation time of the finger from the magneto-resonance absorption signal is determined. A blood glucose concentration in a human body is determined from a correlation between a pre-determined blood glucose concentration in the human body and the determined magneto-resonance spin-lattice relaxation time.

NMR spin echo signals are corrected for axial motion of the borehole logging tool. The correction is applied to an averaged echo train using an average velocity determined from surface measurements over the duration of averaging of the echo trains. An additional correction may be applied to correct for excess polarization or incomplete polarization of nuclear spins due to an insufficient wait time between pulse sequences.

A magnetic resonance imaging white matter hyperintensities region recognizing method and system are disclosed herein. The white matter hyperintensities region recognizing method includes receiving and storing a FLAIR MRI image, a spin-lattice relaxation time weighted MRI image, and a diffusion weighted MRI image. Registration and fusion are preformed, and a white matter mask is determined. An intersection image of the FLAIR MRI image and the white matter mask is taken, a first region is determined after normalizing the intersection image, a cerebral infarct region is removed from the first image through the diffusion weighted MRI image, and then a determination is made as to whether to remove a remaining region in order to form a white matter hyperintensities region in the FLAIR MRI image.

Gas generation of a non-aqueous electrolyte battery having a negative active material that intercalates / deintercalates lithium ions at a potential not lower than 1.2 V relative to the potential of lithium as negative electrode is suppressed.A non-aqueous electrolyte battery comprising a non-aqueous electrolyte containing an electrolyte salt and a non-aqueous solvent, a positive electrode and a negative electrode is characterized in that the main active material of said negative electrode is an active material that intercalates / deintercalates lithium ions at a potential not lower than 1.2 V relative to the potential of lithium and the auxiliary active material of said negative electrode is an active material that at least intercalates lithium ions at a potential lower than 1.2 V relative to the potential of lithium and that there exists lithium showing a spin-lattice relaxation time (T1) of not less than 1 second as determined by a solid-state Li—NMR measurement in the main active material of said negative electrode. A method of manufacturing a non-aqueous electrolyte battery containing a non-aqueous electrolyte, a positive electrode and a negative electrode (a main active material and an auxiliary active material of the negative electrode) is characterized in that the negative electrode potential is lowered to not higher than 0.8 V relative to the potential of lithium at least once in the initial cycle.

The invention discloses an angle and T1 simultaneous measurement method based on a hyperpolarized gas spectrum, and the method comprises the steps: collecting hyperpolarized gas; enabling a research object to obtain the hyperpolarized gas; fixing an excitation angle theta of a radio frequency pulse in one breath holding process, collecting a magnetic resonance spectrum of the hyperpolarized gas ofthe research object, and obtaining a free induction decay signal FID1 of the hyperpolarized gas of the research object in a variable repetition time TR1 and a free induction decay signal FID2 of thehyperpolarized gas of the research object in a fixed repetition time TR2; processing the FID1 and FID2 signals, and obtaining an actual excitation angle theta(r) of the radio frequency pulse and the spin-lattice relaxation time constant T1 of the hyperpolarized gas of the research object. According to the invention, the method can achieve the simultaneous obtaining of the angle and an analytical solution of T1, shortens the sampling time, reduces the requirements for hardware, is easy for engineering implementation, and is simple in data processing.