69 results about "ESR - Electron spin resonance" patented technology

The invention discloses a novel nano-drug Res (at) LDH and a preparation method and application thereof.Germanium-doped LDH powder and resveratrol are combined to obtain a nanoscale particle mixed material Res (at) LDH, electron paramagnetic resonance (EPR) tests show that both the germanium-doped LDH and the traditional drug resveratrol show excellent reactive oxygen species (ROS) removal characteristics, and the Res (at) LDH can be used for preparing a novel nano-drug Res (at) LDH. The nano-drug Res (at) LDH formed by combining the two has remarkable synergistic ROS removal efficiency which can reach 90%. Meanwhile, in-vivo biological distribution experiments show that the novel nano-drug Res (at) LDH has excellent blood-brain barrier permeability, enhances accumulation in brain tissues, improves neurological dysfunction, reduces infarct volume, shows strong antioxidant activity, and inhibits release of pro-inflammatory cytokines.

A solid-state electronic miniature clock featuring a multi-layered silicon chip. A first circuit layer includes an electron paramagnetic resonance sensor, while the second layer comprises a silicon substrate with an etched trench housing single atom-doped fullerene molecules. Magnets are strategically placed on the silicon substrate and a third circuit layer to establish a baseline magnetic field. The chip incorporates through silicon vias (TSVs) filled with copper, forming a copper coil for enhanced antenna performance. Thermal management is achieved through vacuum cavities for isolation, strategically placed metals for heat generation, and thermo-electric materials, such as a bilayer of Bi$_2$Te$_3$ and Bi$_2$Se$_3$, for temperature regulation. A feedback loop monitors and adjusts the temperature, ensuring stability. Fabrication techniques include Deep Reactive Ion Etching (DRIE), electrochemical deposition, and photolithographic patterning, providing precise control over the chip's structure and functionality.

The application relates to the field of catalysis, and discloses an aluminum oxide, a preparation method and application thereof, and a solid state 27 The Al magic angle spinning nuclear magnetic resonance spectrum has characteristic peaks between 16-51 ppm, and the electron paramagnetic resonance spectrum of the aluminum oxide has characteristic peaks at g=2.002-2.004. The surface and the interior of the aluminum oxide material provided by the application have F color centers, the aluminum oxide material can activate hydrogen under mild conditions, does not need to exist in the presence of a transition metal species, and catalyzes hydrogenation of a compound containing a carbon-carbon unsaturated bond.

The invention relates to the technical field of free radical detection, and provides an in-situ electrochemical electron paramagnetic resonance spectrum test assembly and a detection method.The in-situ electrochemical electron paramagnetic resonance spectrum test assembly comprises a pool body and two electrodes, a containing cavity is formed in the pool body, and the containing cavity is used for containing a mixed solution to be detected. And the cell body is provided with a liquid injection hole and two electrode holes which are communicated with the accommodating cavity and the outside. The two electrodes are inserted into the containing cavity, one part of one electrode extends out of the cell body through one electrode hole, and one part of the other electrode extends out of the cell body through the other electrode hole. According to the in-situ electrochemical electron paramagnetic resonance spectrum testing assembly, the electrodes are inserted into the accommodating cavities and extend out of the pool body through the corresponding electrode holes, so that the electrodes are connected with a power supply and electrify and electrolyze a mixed solution in the accommodating cavities, and the electrolysis requirement in the free radical detection process is met; the method can be simultaneously suitable for free radical detection processes without electrolysis or needing electrolysis, and is better in applicability.

An electron paramagnetic resonant (EPR) instrument able to determine chemical properties of a sample using paramagnetic resonance is provided. In one embodiment, the instrument is able to measure the paramagnetic concentration of a wide variety of practical substances, ranging from food and beverages to biological specimens and solid-state electronic materials. The disclosed device can be portable and perform a measurement faster than commonly used techniques to quantify this parameter, including methods that use vibrating sample magnetometers and currently available electron paramagnetic resonance spectrometers.

The invention provides a decoupling phase closed-loop locking nuclear magnetic resonance gyroscope, and particularly relates to a nuclear magnetic resonance gyroscope based on modulation and demodulation of an alternating current reference line magnetic field, which is characterized in that an alternating current reference modulation magnetic field different from nuclear spin resonance frequency is applied along the direction of detection light; meanwhile, alternating current modulation is conducted on the decoupling phase of the nuclear magnetic resonance gyroscope electron paramagnetic resonance magnetometer, alternating current reference modulation amplitude changes are demodulated, a decoupling phase error signal is obtained, and real-time closed-loop locking of the decoupling phase is achieved through a closed-loop control system based on the error signal. According to the invention, real-time closed-loop locking of the decoupling phase of the nuclear magnetic resonance gyroscope can be realized, and decoupling phase fluctuation caused by fluctuation of system parameters such as laser power, frequency and air chamber temperature is inhibited, so that the angular rate measurement precision and long-term stability of the nuclear magnetic resonance gyroscope are improved. According to the technical scheme, the technical problems that in the prior art, a double-shaft differential detection method is prone to being affected by amplitude fluctuation, large errors exist, and operation is complex are solved.

The invention discloses a double sulfur vacancy SV-Bi2S3 / SV-ZnIn2S4 heterojunction photocatalyst as well as a preparation method and application of the double sulfur vacancy SV-Bi2S3 / SV-ZnIn2S4 heterojunction photocatalyst. According to the double-sulfur-vacancy SV-Bi2S3 / SV-ZnIn2S4 composite photocatalyst, the existence of the sulfur vacancy in a composite material is proved through electron paramagnetic resonance. In addition, a scanning electron microscope, X-ray diffraction and Fourier infrared analysis show that the results show that the composite materials interact with one another and have tight interface contact. In addition, the double-sulfur-vacancy SV-Bi2S3 / SV-ZnIn2S4 composite photocatalyst prepared by the preparation method disclosed by the invention has the characteristics of good structural stability and recyclability, so that the treatment cost is greatly reduced. Meanwhile, the catalyst is low in cost, chloroquine phosphate in the wastewater can be quickly decomposed and converted, the wastewater treatment efficiency is greatly improved, and the requirement of large-scale industrial application is met.

The invention provides a negative electrode material and a preparation method thereof, and a battery, the negative electrode material comprises an active substance, the active substance comprises silicon, a silicon oxide and a compound of a metal element M, the compound of the metal element M comprises a silicate of the metal element M and / or an oxide of the metal element M; the negative electrode material is measured through electron paramagnetic resonance, the g factor value of an electron spin resonance signal of oxygen atoms is X, and X is larger than or equal to 2.00601 and smaller than or equal to 2.00699; the oxygen vacancy intensity is Y, and Y is more than or equal to 10G and less than or equal to 400G. The negative electrode material provided by the invention has proper oxygen vacancies, a stable lithium ion channel exists in the battery cycle process, the expansion effect of the negative electrode material can be improved, and the cycle stability can be improved.

The invention relates to the field of electron paramagnetic resonance spectrum testing equipment, in particular to a sampling device for in-situ testing of an electron paramagnetic resonance spectrum. A sample introduction device for electron paramagnetic resonance spectrum in-situ testing comprises a micro-fluidic chip, a clamping assembly, a sample introduction pipe A, a sample introduction pipe B and a split type injection pump, and a sample introduction port A, a sample introduction port B and a sample outlet are formed in the micro-fluidic chip; one end of the sample injection pipe A is communicated with the sample injection port A, and the other end of the sample injection pipe A is communicated with the split type injection pump; one end of the sample injection pipe B is communicated with the sample injection port B, and the other end of the sample injection pipe B is communicated with the split type injection pump; a sample outlet of the micro-fluidic chip is communicated with a quartz test tube. Rapid switching of reactant concentration or solvent proportion can be achieved by controlling the flow speed of the A / B tube, a tedious sample preparation process is not needed, and the suitability and flux of electron paramagnetic resonance spectrum in-situ testing can be greatly improved.

The invention relates to a method for detecting in-situ free radicals in a hydroxylamine nitrate catalytic decomposition process, which comprises the following steps: 1, catalytic decomposition: catalyzing a hydroxylamine nitrate solution to decompose by using a metal supported catalyst to obtain a decomposition solution; step 2, OH <-> detection: adding an OH <-> free radical scavenger solution into the decomposition liquid obtained in the step 1 to obtain a stable OH <-> free radical adduct, namely a DMPO-OH <-> free radical adduct; step 3, NO. Detection: adding a NO. Free radical scavenger solution into the decomposition liquid obtained in the step 1 to obtain a stable NO. Free radical adduct, namely an (MGD) 2-Fe < 2 + >-NO. Free radical adduct; 4, EPR detection, wherein OH. Free radical adducts and NO. Free radical adducts obtained in the step 2 and the step 3 are detected through an electron paramagnetic resonance instrument. The detection method has the characteristics of proper magnetic field penetration depth, no background interference, continuous and repeated detection and the like.

The use of a cell-permeant molecular probe to assay the presence, and monitor the production, of the reactive oxygen species, superoxide, in red blood cells (RBCs) is described. The assay is performed using electron paramagnetic resonance (EPR) spectroscopy and a cell-permeant hydroxylamine spin trap. The cell-permeant molecular probe is not detected or quantifiable by EPR in its reduced form. However, upon entering the RBCs, the probe is oxidized by reacting with superoxide to yield a stable nitroxide radical that is detected and quantified using EPR. Our studies indicate that superoxide production is consistent with RBC metabolism that predicts lipid oxidation, membrane injury and poor post-transfusion performance. Therefore, measurement of reactive oxygen species can be used as an indicator of RBC quality at the time of donation and after storage.

The invention relates to application of a metal fullerene-organic framework composite spinning functional material in oxygen detection, and belongs to the technical field of metal fullerene composite materials. The metal fullerene-organic framework composite spinning functional material has sensitive response characteristics to oxygen molecules, and realizes real-time in-situ monitoring of oxygen gas adsorption, diffusion and concentration change processes by combining an electron paramagnetic resonance technology, so that a new method is added for an oxygen analysis technology, and oxygen analysis requirements under different working conditions are met.

A system for mapping oxygen levels in tumors includes a needle that is sized to deliver high dose rate brachytherapy to tissue into which the needle is inserted, where the needle includes a radio frequency micro-coil sensor positioned within a shaft of the needle and a spin probe mounted to an outer surface of the shaft of the needle. A processor is in communication with the needle and configured to move the radio frequency micro-coil sensor along the shaft of the needle. The processor is also configured to receive, from the radio frequency micro-coil sensor, oxygen level readings at a plurality of tissue locations along the shaft of the needle. The processor is also configured to generate an oxygen level mapping of the tissue based on the oxygen level readings received from the radio frequency micro-coil sensor.

The invention discloses an electron paramagnetic resonance probe and an electron paramagnetic resonance spectrometer. The electron paramagnetic resonance probe comprises a metal probe body; the metal probe body comprises a first auxiliary resonant cavity, a first gap, a main resonant cavity, a second gap and a second auxiliary resonant cavity which are sequentially arranged along a first direction; the first auxiliary resonant cavity is communicated with the main resonant cavity through a first gap; the main resonant cavity is communicated with the second auxiliary resonant cavity through a second gap; the boundary of the main resonant cavity comprises a first arc and a second arc which are oppositely arranged at an interval; the first arc and the second arc are symmetrical about a first symmetry axis which is parallel to the first direction; the boundary of the first auxiliary resonant cavity and the boundary of the second auxiliary resonant cavity are symmetrical about a second symmetry axis of the first circle, and the straight line where the second symmetry axis is located is perpendicular to the first direction. According to the electron paramagnetic resonance probe and the electron paramagnetic resonance spectrometer, the structure is simple, the manufacturing cost is low, the uniformity of the magnetic field in the main resonant cavity is good, and the magnetic field intensity is large.

A low field MRI instrumental system includes: an electromagnetic Radio Frequency antenna to emit RF pulses for inducing Electron Paramagnetic Resonance; an electromagnetic Low Frequency antenna for measurements, to emit LF pulses for inducing Nuclear Magnetic Resonance, respectively to receive LF signal produce by NMR; a gradient generator, to create a gradient in a static magnetic field generated during measurements; a high field generator to generate a strong pre-polarization magnetic field for magnetic pre-polarization; and, a control / command unit. This low field MRI instrumental system further includes a low field unit to generate a low static magnetic field whose direction is adjustable along the three directions X, Y and Z of a fixed reference frame associated with the low field MRI instrumental system.

This application provides a magnetic nanoscale temperature measurement method, device, electronic device, and storage medium based on particle size distribution correction, relating to the field of nanomaterials technology. The method includes: acquiring the electron paramagnetic resonance (EPR) spectrum of magnetic nanoparticles in a target environment, as the target EPR spectrum; extracting the positive and negative peak amplitudes, resonance magnetic field, and peak-to-peak width from the target EPR spectrum, as the target positive and negative peak amplitudes, target resonance magnetic field, and target peak-to-peak width; and calculating the temperature corresponding to the target positive and negative peak amplitudes, target resonance magnetic field, and target peak-to-peak width based on a pre-constructed temperature measurement model, as the temperature of the target environment. The temperature measurement model characterizes the relationship between temperature and the positive and negative peak amplitudes, resonance magnetic field, and peak-to-peak width of the EPR spectrum of the magnetic nanoparticles. The temperature measurement model is constructed based on the particle size distribution of the magnetic nanoparticles. Using this embodiment can improve the accuracy of magnetic nanoscale temperature measurement.

A method for relaxation time determination includes delivering a series of radio frequency (RF) pulses in a sequence to a specimen having a magnetic resonance spin system. The pulses are separated by equal time intervals and the sequence has a duration comparable or greater than a spin-lattice relaxation time for the spin system. The method includes receiving a response after each RF pulse in the series. The response includes a free induction decay and spin echoes. The method includes generating a series of single point imaging (SPI) images from each response. Each SPI image of the series corresponds to an RF pulse in the series. The method includes converting SPI images to a spin-spin relaxation map and a spin-lattice relaxation map.

The invention relates to the technical field of industrial flue gas treatment process monitoring and control, in particular to a flue gas denitration reaction process online monitoring method, system and device based on electron paramagnetic resonance, and aims to solve the problems of hysteresis of indirect monitoring and failure in diagnosis of fault root causes in the prior art. A high-temperature micro-reactor arranged in a flue is adopted as an external resonant cavity and is connected with a normal-temperature EPR detection unit arranged outside the flue through a waveguide, so that in-situ, online and direct monitoring on key free radical concentration and catalyst state in a denitration reaction process is realized. Through a multi-parameter fusion diagnosis method, EPR signals are converted into process parameters, intelligent diagnosis is carried out, and unprecedented process data support is provided for accurate control and fault early warning of a denitration system.

The invention discloses a preparation method of a radix astragali extracting solution with high antioxidant activity and the extracting solution, and aims to solve the problems of low extraction rate of active substances and inaccurate detection of antioxidant activity in the prior art. According to the method, five factors including ethanol content, extracting solution multiple and the like are taken as key variables, U10 * (108) uniform test design is adopted, the DPPH free radical scavenging rate is accurately determined by combining an electron paramagnetic resonance technology, and the contents of astragaloside, general flavone and polysaccharide are synchronously detected. A quantitative model is established through multivariate linear regression analysis, and the optimal process parameters are determined: the ethanol content is 80%, the extracting solution multiple is 4, the temperature is 85 DEG C, the time is 1.5 h, and the extraction time is 1 time. The DPPH free radical scavenging rate of the extracting solution prepared through the technology is larger than or equal to 92.75%, polysaccharide is larger than or equal to 12520 mg / L, total flavone is larger than or equal to 323.77 mg / L, astragaloside is larger than or equal to 257 mg / L, synergistic efficient extraction of multiple components is achieved, and the extracting solution is suitable for industrial production.

The invention relates to the technical field of medical image reconstruction, in particular to a finite angle electron paramagnetic resonance imaging method, system and device based on high-order direction total variation, and the method comprises the steps: obtaining sparse and finite angle projection data of a to-be-reconstructed image; according to the sparse and limited angle projection data in the to-be-reconstructed image, constructing an optimization model based on the high-order direction total variation, and reconstructing the to-be-reconstructed image by using the optimization model; and the optimal model is solved by adopting a Chambolle-Pock solving algorithm, so that a reconstructed electron paramagnetic resonance image can be obtained. According to the method, non-constant characteristics can be effectively handled, and textural features and edge information of the image can be maintained.

The invention discloses a silicon-carbon material and a preparation method thereof, a negative electrode and a battery, the silicon-carbon material comprises silicon-carbon particles, the silicon-carbon particles comprise porous carbon and silicon nano-particles, at least part of the silicon nano-particles are located in pores of the porous carbon, and at least part of the silicon nano-particles are located in the pores of the porous carbon. An electron paramagnetic resonance spectrogram of the porous carbon has symmetrical vacancy defect signal peaks, the line width delta H of the symmetrical vacancy defect signal peaks is 25-75 G, and the intensity of the symmetrical vacancy defect signal peaks is 1 * 10 < 4 >-2 * 10 < 5 > a.u. The silicon carbon material disclosed by the invention has relatively high stability.

The invention discloses a multi-parameter test optical fiber preform quality detection and grading method and device, and the method comprises the steps: carrying out the electron probe microscopic analysis test, Raman spectrum test and electron paramagnetic resonance test of an optical fiber preform sample, and obtaining element distribution data, Raman spectrum data and paramagnetic resonance spectrum data; performing preprocessing and feature extraction on the element distribution data, the Raman spectrum data and the paramagnetic resonance spectrum data to obtain a plurality of key quality parameters; inputting the plurality of key quality parameters into a pre-trained comprehensive quality evaluation model, and calculating to obtain a comprehensive quality evaluation coefficient of the optical fiber preform; and comparing the comprehensive quality evaluation coefficient with a preset grading threshold value, and carrying out quality grading on the optical fiber prefabricated member. According to the method, three testing modes are adopted, a plurality of key quality parameters are obtained, the detection dimension is enriched, the comprehensive quality evaluation coefficient is calculated through the model, and subjective errors of operators are reduced.

An electron paramagnetic resonance (=EPR) spectrometer (1), comprising - a sample resonator (2), comprising a sample area (3) for a measurement sample (4) to be held in the sample resonator (2); - a tunable microwave source (7), for generating a tunable microwave signal to be applied to the sample resonator (2), - a magnet system (5), for generating a variable magnetic field to be applied at least to the sample area (3) in the sample resonator (2), and - and a microwave detector (9) connected to the sample resonator (2) for detecting microwave radiation, is characterized in that the tunable microwave source (7) comprises - a fixed frequency microwave oscillator (20), for generating a fixed frequency microwave signal, - a tunable frequency generator (27), for generating a tunable high frequency (=HF) signal, wherein the tunable HF signal is of lower frequency as compared to the fixed frequency microwave signal, and - a mixer (32), for mixing the fixed frequency microwave signal and the tunable HF signal, thus generating a tunable microwave signal. The invention provides an EPR spectrometer with high spectral resolution, which is simple and inexpensive in production and operation.

Various examples are provided related to bimodal electron paramagnetic resonance (EPR). In one example, a bimodal resonator includes a detection coil; first and second excitation coils, where the excitation coils are non-parallel separated by a fixed angle; and excitation controllers coupled to the first and second excitation coils. The excitation controllers can adjust radio frequency (RF) fields generated by the first and second excitation coils to produce a resonator field substantially parallel with the detection coil. In another example, a method including generating a first RF field by exciting the first excitation coil; generating a second RF field by exciting the second excitation coil; and producing a resonator field substantially parallel with a detection coil of the bimodal resonator by adjusting the RE field of the first excitation coil, the RF filed of the second excitation coil, or both.

The invention provides an analytical method suitable for a mechanism of generating free radicals through oxidation reduction and initiated polymerization thereof, in-situ attenuated total reflection infrared spectrum equipment is adopted in a linkage manner, and is used for tracking molecular vibration characteristic peak dynamic changes of reactants, intermediates and products in the reaction process and optimizing an in-situ electron paramagnetic resonance spectrum monitoring system, so that the system can be used for analyzing the free radicals in the reaction process. The method is used for identifying the variety of free radicals generated in the reaction process and the change rule of the strength of the free radicals along with time in real time, analyzing the redox reaction path based on infrared spectrum data and free radical data, and is particularly suitable for dynamically monitoring and analyzing the free radicals generated by redox so as to analyze the mechanism of generating the free radicals by redox.

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 invention provides an electro-catalytic reaction device for electron paramagnetic resonance detection, and relates to the technical field of electrochemistry. The electro-catalytic reaction device comprises an upper end cover, a cylindrical shell, a lower end cover and a pump, one end of the cylindrical shell is hermetically connected with the upper end cover, and the other end of the cylindrical shell is hermetically connected with the lower end cover to form an electro-catalysis reaction tank; the upper end cover comprises three orifices, a reference electrode is placed in the first orifice in a sealed manner, a counter electrode is placed in the second orifice in a sealed manner, and the third orifice is used as an electrolyte inflow port; the lower end cover comprises two orifices, one orifice is hermetically provided with a working electrode, and the other orifice is used as an electrolyte outlet; and the pump is used for pumping the electrolyte from the electrolyte inlet and pumping the electrolyte from the electrolyte outlet. The device is simple in structure, gas can be effectively prevented from being accumulated in the electrolytic bath, and the accuracy of electron paramagnetic resonance detection is improved.

The invention belongs to the technical field of detection, relates to a free radical detection method, particularly provides a method for detecting water free radical cations by using DMPO, and aims to realize efficient, rapid, simple and convenient water free radical cation detection convenient for analysis. The method comprises the following steps: by taking an electron paramagnetic resonance spectrum technology as a detection tool and 5, 5-dimethyl-1-pyrroline-N-oxide (DMPO) as a spin trapping agent, applying voltage to water, adding a DMPO aqueous solution with a certain concentration into a reacted solution, and carrying out water free radical cation detection on the solution; a corresponding spectrogram is obtained through electron paramagnetic resonance testing, the spectrogram is fitted, and spectrogram characteristic peaks are analyzed to represent water free radical cations. The method can be used for efficiently, quickly and simply detecting the water free radical cations, is convenient for analyzing the water free radical cations, and has popularization value and application prospect.

A microwave power amplifier arrangement for an electron paramagnetic resonance (EPR) system provides amplified microwave pulses having a microwave frequency in the X-band. The arrangement has a microwave input and a microwave output, and comprises at least one transistor amplifier device, and at least one switchable reflection device. A respective transistor amplifier device comprises a transistor amplifier device input directly or indirectly connected to the microwave input (2), at least one transistor, and a transistor amplifier device output directly or indirectly connected to the microwave output. A respective switchable reflection device comprises a PIN diode and a lambda / 4 line connected directly or indirectly to the transistor amplifier device output of at least one transistor amplifier device and to a first port of the PIN diode, with lambda being the wavelength of the microwave radiation within the lambda / 4 line. A second port of the PIN diode is connected to ground.

The invention discloses a method and a system for spectrogram analysis. A method for spectrogram analysis includes: acquiring an electron paramagnetic resonance (EPR) spectrogram signal, a category corresponding to the EPR spectrogram signal, and a microwave frequency utilized to generate the EPR spectrogram signal; the EPR spectrogram signal is converted into a two-dimensional image signal; and generating an interval value of a fitting parameter based on the two-dimensional image signal and the microwave frequency using a deep learning prediction module corresponding to the category.