44 results about "Water proton" patented technology

The invention relates to a method of MR imaging of at least a portion of a body of a patient placed in an examination volume of an MR device. The object of the invention is to improve CEST contrast enhanced imaging. The method of the invention comprises the following steps: a) saturation of nuclear magnetization of exchangeable protons of a CEST contrast agent administered to the patient by subjecting the portion of the body to at least one frequency-selective saturation RF pulse matched to the MR frequency of exchangeable protons of the CEST contrast agent, wherein the saturation period, i.e. the duration of the frequency-selective saturation RF pulse, is shorter than the time required for saturation to build up a full CEST contrast enhancement effect when starting from zero saturation; b) generating at least one MR signal of water protons of the body by subjecting the portion of the body to an MR imaging sequence comprising at least one RF pulse and switched magnetic field gradients; c) acquiring and sampling the at least one MR signal from the body; d) repeating steps a) to c) a number of times under variation of parameters of the MR imaging sequence, wherein MR signals are acquired and sampled during a saturation build-up period, i.e. before a steady state of the CEST effect is achieved; e) reconstructing a proton-density weighted, CEST contrast-enhanced MR image from the acquired and sampled MR signals.

Charged spray droplets are guided in a pseudopotential distribution generated by audio frequency voltages at electrodes of a guiding device, focusing the spray droplets toward the axis. An axial electric field profile and an axial flow profile of a drying gas in the guiding device allow the drift of different-sized droplets to be controlled in the longitudinal direction of the guiding device, so that the droplets are roughly equal in size when they leave the guiding device and finally dry up shortly after leaving. As a result, the ions are formed in a relatively small spatial region. Electrostatic potentials guide the analyte ions from this small spatial region to the entrance aperture of the inlet capillary; during this process, very light ions, especially protons and water-proton complexes, can be filtered out by a mobility filter.

Featured are methods for magnetic resonance imaging of a volume, such a volume having susceptibility-generating objects or interfaces having susceptibility mismatches therein. Such a method includes selectively visualizing one of susceptibility-generating objects or interfaces having susceptibility mismatches as hyperintense signals, where such visualizing includes controlling variable imaging parameters so as to control a geometric extent of a signal enhancing effect, m more particular aspects of the present invention, such selectively visualizing includes attenuating or essentially suppressing signals from fat and / or water, namely on-resonant water protons, so as to thereby enhance a signal(s) associated with magnetic susceptibility gradient(s). Also featured are MRI systems, apparatuses and / or applications programs for execution on a computer system controlling the MRI data acquisition process embodying such methods.

The present invention relates to a magnetic resonance structure with a cavity or a reserved space that provides contrast and the additional ability to frequency-shift the spectral signature of the NMR-susceptible nuclei such as water protons by a discrete and controllable characteristic frequency shift that is unique to each MRS design. The invention also relates to nearly uniform solid magnetic resonance T2* contrast agents that have a significantly higher magnetic moment compared to similarly-sized existing MRI contrast agents.

The invention discloses a state monitoring method for a proton exchange membrane fuel cell. The state monitoring method comprises the following steps: introducing the optimal size of a V-I characteristic curve slope k as a control index for a stable working state of the fuel cell; and generating a control signal according to information of measured k, and controlling operating conditions of the fuel cell, thereby adjusting the fuel cell to work on an ohm segment. The invention further discloses a state monitoring system for the fuel cell. The state monitoring system comprises a fuel cell stack (the optimal working temperature is 60 DEG C), a hydrogen supply pipeline system, an air supply pipeline system, a cooling water circulation system, an exhaust discharge system, an impedance testing system, a safety monitoring system and a detection control system. The V-I characteristic curve slope k of the fuel cell is obtained through the detection control system; with k as the control index, the fuel cell quickly restores to the ohm segment; the possibility of water logging and membrane dryness of a proton exchange membrane is lowered; and the performance of the fuel cell is greatly improved.

The invention relates to a method of Dixon-type MR imaging. It is an object of the invention to provide a method that enables Dixon water / fat separation with high SNR and with improved noise propagation in the water / fat separation. The method comprises the steps of: —subjecting an object (10) to a first imaging sequence, which generates a number of differently phase encoded first MR echo signals at a first echo time, such that contributions from MR signals emanating from water protons and MR signals emanating from fat protons to the first MR echo signals are essentially in phase, —acquiring the first MR echo signals using a first signal receiving bandwidth, —subjecting the object (10) to a second imaging sequence which generates a number of differently phase encoded second MR echo signals at a second echo time, such that contributions from MR signals emanating from water protons and MR signals emanating from fat protons to the second MR echo signals are at least partially out of phase, —acquiring the second MR echo signals using a second signal receiving bandwidth which is larger than the first receiving bandwidth, wherein the number of phase encodings of the first imaging sequence is smaller than the number of phase encodings of the second imaging sequence, and —reconstructing a MR image from the first and second MR echo signals, whereby signal contributions from water protons and fat protons are separated. Moreover the invention relates to a MR device and to a computer program to be run on a MR device.