6 results about "Spin echo" patented technology

This disclosure provides a nuclear magnetic resonance (NMR) analysis method for establishing the chemical composition and condensed-state structure of fluorine-containing materials and its application. The method includes: placing fluorine-containing materials under different operating conditions in a single-sided NMR spectrometer; under a single-sided inhomogeneous magnetic field environment; presetting parameters for a spin echo pulse sequence; using the spin echo pulse sequence to excite fluorine and hydrogen nuclei in the fluorine-containing material to obtain coupled NMR signals of fluorine and hydrogen nuclei; determining echo peak data from the coupled NMR signals according to the preset parameters; processing the echo peak data according to the structural characteristics of the fluorine-containing material to obtain relaxation spectrum fingerprint data; performing data transformation on the relaxation spectrum fingerprint data to obtain transverse relaxation time data; and establishing a relaxation spectrum fingerprint database and a transverse relaxation time database of the coupling of fluorine and hydrogen nuclei in the fluorine-containing material based on the relaxation spectrum fingerprint data and transverse relaxation time data under different operating conditions.

The application discloses a kind of nuclear magnetic resonance spectrum peak position detection method, device and readable medium, by obtaining two-dimensional spectrum based on spin echo phase change spectrum, SEcho-Net neural network is constructed and trained, SEcho-Net neural network includes coding layer and decoding layer, coding layer includes indirect dimension down-sampling module and direct dimension down-sampling module, indirect dimension down-sampling module is used to compress two-dimensional spectrum based on spin echo phase change spectrum, and first feature vector is obtained, first feature vector is input in direct dimension down-sampling module and extracts key information related to spectrum peak position, and obtains key feature, and decoding layer includes direct dimension up-sampling module and step-by-step dimension reduction module, direct dimension up-sampling module is used to recover spectrum information from key feature, and second feature vector is obtained, and second feature vector is input in step-by-step dimension reduction module and carries out feature extraction, and obtains spectrum peak pure chemical shift position information.The method has low experimental requirements, and can accurately locate spectrum peak position.

Disclosed in the present invention are a 3D navigator-based 3D gradient spin-echo diffusion imaging method, and a device. The method comprises: first, using a global saturation module to destroy previous residual transverse magnetization; second, by means of a diffusion encoding module, embedding a pair of trapezoidal cosine oscillation gradients or pulse gradients into radio frequency pulses of 90°x-180°y-90°-x, and separating diffusion encoding from signal acquisition; then using a fat saturation module to suppress a fat signal; using a 3D gradient spin-echo readout method to acquire an image signal; and finally, acquiring a 3D navigation echo signal in the last spin echo for correcting a phase error between multiple excitations. The present invention can effectively eliminate phase errors between multiple acquisitions and realize high-resolution whole-brain diffusion imaging. Compared with 2D echo planar imaging, the present invention increases the signal-to-noise ratio of diffusion magnetic resonance imaging, thereby supporting higher-resolution whole-brain 3D diffusion magnetic resonance imaging.

The application provides a small animal sciatic nerve magnetic resonance coil and an imaging method, and the method comprises the following steps: filling a high-concentration sugar syrup solution at the bottom of the magnetic resonance coil and performing constant temperature control; placing a small animal in a prone position in the high-concentration sugar syrup solution and discharging air in the gap between the lower limbs and below the abdomen of the small animal; after performing magnetic resonance positioning scanning to determine the main sequence scanning range, starting the main sequence scanning, suppressing the flow tissue signal through a pre-pulse combination, exciting the tissue by using a radio frequency pulse with preset parameters, acquiring echo signals by combining a fast spin echo technology and filling K space, and obtaining scanning original data; performing preprocessing on the scanning original data and accurate segmentation of the sciatic nerve and spinal nerve to obtain a segmentation result; and completing three-dimensional model reconstruction, optimization and multi-modal fusion visualization based on the segmentation result to obtain an image scanning result. The application is suitable for small animals, is accurate in imaging, can effectively suppress various kinds of artifacts, and can be widely applied to sciatic nerve imaging scenarios of small animals.

The application discloses a remanence measuring method based on magnetic resonance echo phase shift difference. In the method, the test direction is the same as the scanning direction, the difference between the action of the magnetic field non-uniformity on the spin echo and the gradient echo is utilized, the change of the magnetic field uniformity caused by the test gradient is measured, and the remanence intensity is measured by using the difference between the phase changes of the two echoes caused by the change. The method overcomes the problem that the multi-path gradient is not completely balanced to affect the test gradient and further affect the remanence measurement, eliminates the influence of the flat echo signal peak shape and the peak value drop on the measurement accuracy and stability, and guarantees the effectiveness of the test in the non-coordinate axis direction. In addition, the method does not need additional measuring instruments, the measuring process is simple and easy to implement, and the spatial anisotropy of the remanence can be measured. The method can be used for evaluating the influence of the remanence on the imaging space positioning, and is particularly suitable for judging whether the permanent magnetic resonance imaging system meets the requirements of the space positioning for monitoring and navigation in the interventional treatment.

This application relates to a quantum parity measurement method and apparatus. The method includes: initializing the quantum bit by adjusting the resonance between the quantum bit and a superconducting resonator through a DC bias; preparing the parity state vector of the quantum bit onto the -Y axis through an X / 2 quantum bit gate; preparing the parity state vector of the quantum bit onto the -X axis and X axis respectively by controlling the gate electrode and the X quantum bit gate; and preparing the parity state vector of the quantum bit onto the Z axis and -Z axis respectively via the Y / 2 quantum bit gate. According to the quantum parity measurement method and apparatus provided in this application, by controlling the deviation of the gate electrode from the degeneracy point, the parity phase difference can be controllably accumulated in the middle of the spin echo sequence, achieving parity mapping while also resisting low-frequency noise in the system. Therefore, this application can simultaneously achieve the requirements of high fidelity, high time resolution, and rapid system calibration.