8 results about "Dynamic nuclear polarisation" patented technology

The application relates to a molten DNP cross-polarization probe which comprises a resonant cavity, an intracavity assembly, a flange, a double-resonance circuit and a radio frequency rod; the resonant cavity is a hollow cylindrical structure with an upper opening; the intracavity assembly is arranged in the interior of the resonant cavity and comprises a coil unit arranged in the middle of the resonant cavity and a mirror unit arranged outside the coil unit; the flange is buckled to the upper end of the resonant cavity, a first through hole is formed in the middle of the flange, a second through hole is formed outside the first through hole, and the double-resonance circuit is arranged at the upper end of the flange; and the radio frequency rod is connected with the coil unit in the interior of the resonant cavity through the second through hole. The application successfully realizes the application of the cross-polarization technology means in the molten dynamic nuclear polarization technology and solves the technical problems of low nuclear polarization degree and long polarization time.

The invention discloses a waist-adjustable structure-integrated square elbow of a DNP-NMR (Dynamic Nuclear Polarization Nuclear Magnetic Resonance) system transmission line. The waist-adjustable structure-integrated square elbow structurally comprises two corrugated waveguide structures, a right triangle cavity, a metal ellipsoid mirror surface and two external flange structures. The square elbow is installed in a transmission line, and the corrugated waveguide receives an HE11 mode coupled by a Gaussian fundamental mode from a gyrotron, so that long-distance transmission with small loss and low cross polarization is realized in a transmission line system; the right triangle cavity is connected with the two ends of the corrugated waveguide, an HE11 mode transmitted in the corrugated waveguide is recoupled into a Gaussian base mode at the position, the transmission direction of a wave beam is changed through the metal ellipsoid mirror surface, and the space flexibility of the transmission device is improved. Meanwhile, the metal ellipsoid mirror surface also adjusts the waist radius of the Gaussian fundamental mode so as to match the input requirement of the nuclear magnetic resonance system and keep the phase consistency of the original wave beam at the same time; the external flange structure is used for being tightly connected with other straight waveguide sections, and continuity and collimation of the cavity structure are guaranteed. Compared with a split type part, the integrated square elbow has the advantages that the assembly error of a construction system is obviously reduced, the machining difficulty is low, and the standardization degree is high. And meanwhile, the device can meet the requirements of a dynamic nuclear polarization nuclear magnetic resonance system on high-efficiency, stable, flexible-direction and long-distance transmission of Gaussian beams.

This invention discloses a fluorinated triphenylmethyl radical compound, its preparation method, and its applications. The invention retains the chemical structure of the triphenylmethyl radical and connects it to a fluorinated alkyl chain in a relatively stable manner. Because the fluorinated triphenylmethyl radical compound retains its core radical structure, it can be applied in melt dynamic nuclear polarization technology to achieve efficient polarization transfer from free electron spin to specific nuclear spins in the target sample, thereby increasing the intensity of the NMR signal. The carboxylic acid functional group can be rationally modified into ester or amide bonds without affecting its role as an electron spin provider. The fluorinated triphenylmethyl radical compound synthesized in this invention has fluorocarbon phase properties. Solid-phase extraction using polytetrafluoroethylene micropowder or fluorosilicone allows for rapid and complete separation of the fluorinated triphenylmethyl radical compound from the polarized sample, solving a key problem in current melt dynamic nuclear polarization technology (rapid removal of free radicals from the sample).

The invention belongs to the technical field of nuclear magnetic resonance and electron paramagnetic resonance, and particularly relates to an alpha-keto acid light-excited free radical enhanced generation system for dissolving DNP and application of the alpha-keto acid light-excited free radical enhanced generation system. The invention provides an application of hydrogen peroxide and / or titanium dioxide as a free radical enhancer in a molten dynamic nuclear polarization alpha-keto acid photoexcitation free radical enhanced generation system. According to the alpha-keto acid light excitation free radical enhancement generation system provided by the invention, the free radical enhancer can effectively induce alpha-keto acid molecules to generate free radical reaction under the ultraviolet / visible light illumination condition, so that the yield of transient free radicals is remarkably improved. The alpha-keto acid photoexcitation free radical enhanced generation system provided by the invention can provide a high-concentration free radical source meeting the technical requirements of DNP, promote the efficiency and rate improvement of an electron-nuclear polarization transfer process, and provide a key technical support for the application of a molten DNP technology in the fields of magnetic resonance imaging and the like.

The syntheses of a series of verdazyl mono- and biradicals, as well as verdazyl-nitroxide biradicals, are described for high-field dynamic nuclear polarization nuclear magnetic resonance (DNP NMR) spectroscopy. These radicals were examined in high-field DNP NMR experiments (600 MHz / 395 GHz), by measuring 1H signal enhancements directly and through 13C{1H} cross- polarization experiments. X-band EPR, 1H DNP field profiles, and experiments to determine the nuclear build-up times were performed for verdazyl-nitroxide biradicals VerTEMPol and VerTEKol. These hybrid biradicals provide enhancements of up to 100-fold increased signal intensities, representing >104-fold time savings, and approximately 4 times as high as that of the nitroxide biradical TEKPol, a commonly used polarizing agent in the field.

This invention discloses a multi-channel parallel broadband microwave modulation polarization enhancement device and method. The device includes a nuclear magnetic resonance (NMR) spectrometer, comprising a microwave source, an NMR probe, an RF power amplifier, and a control console. The microwave source includes a signal generation module, one or more parallel microwave output channels, and a combiner. The signal generation module is electrically connected to one or more microwave output channels. The outputs of one or more microwave channels are combined by the combiner and fed into the NMR probe. The RF power amplifier is electrically connected to the probe. The control console controls the microwave source and the RF power amplifier. The method is based on multi-channel parallel microwave pulses with wide spectral characteristics. Frequency modulation is used to optimize the combined microwave pulses to match free radical samples with a certain electron paramagnetic resonance linewidth, achieving efficient dynamic nuclear polarization. This invention can significantly improve the signal-to-noise ratio of the NMR signal while broadening the excitation bandwidth and improving polarization efficiency, effectively shortening the experimental time.

The invention discloses a multichannel parallel broadband microwave modulation polarization enhancement device and enhancement method. The device comprises a nuclear magnetic resonance spectrometer which is composed of a microwave source, a nuclear magnetic resonance probe, a radio frequency power amplifier and a console; the microwave source comprises a signal generation module, one or more parallel microwave output channels and a combiner, the signal generation module is electrically connected with the one or more microwave output channels, output of the one or more microwave output channels is fed into the nuclear magnetic resonance probe after being combined by the combiner, the radio frequency power amplifier is electrically connected with the probe, and the control console controls the microwave source and the radio frequency power amplifier. According to the method, based on multi-channel parallel microwave pulses with wide spectrum characteristics, combined microwave pulses are optimized through a frequency modulation means so as to be matched with a free radical sample with a certain electron paramagnetic resonance line width, and efficient dynamic nuclear polarization is achieved. According to the invention, while the excitation bandwidth is widened and the polarization efficiency is improved, the signal-to-noise ratio of a nuclear magnetic resonance signal is remarkably improved, and the experiment time is effectively shortened.

According to the present invention, a compound having a structure in which a dye for chemically induced dynamic nuclear polarization and a linking group having a functional group for binding to a protein are covalently bonded to each other is reacted with and linked to a protein to be analyzed, the nuclear spin of the protein is highly polarized by the chemically induced dynamic nuclear polarization, and NMR measurement is performed with high sensitivity.