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

A new class of micro- and nano-particulate paramagnetic spin probes useful for magnetic resonance imaging techniques, including electron paramagnetic resonance (EPR) and magnetic resonance imaging (MRI). The probes are lithium phthalocyanine derivative compounds. Also provided are suspensions and emulsions comprising lithium phthalocyanine derivative probes. Also provided are noninvasive methods for measuring noninvasive methods of measuring oxygen concentration, oxygen partial pressure, oxygen metabolism, and nitric oxide concentration in a specific tissue, organ, or cell in vivo or in vitro.

The invention discloses a method for detecting free radical ration in coal tar. The method comprises the steps of removing moisture in the tar in a high speed centrifuging manner, and preserving a tar sample under low temperature or inert atmosphere; adopting a diamagnetism substance to deliquate DPPH(1,1-Diphenyl-2-picrylhydrazyl radical 2,2-Diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl) to prepare a plurality of DPPH standard samples with different free radical concentrations, carrying out EPR (electron paramagnetic resonance) measurement, carrying out secondary integration on an EPR spectrogram, and recording the corresponding secondary integration area; establishing a standard curve according to the free radical contents of the DPPH standard sample with different free radical concentrations and the secondary integration area of the corresponding EPR spectrogram; and filling the tar sample into a pipe, measuring according to the same EPR measuring condition, carrying out secondary integration on the measured EPR spectrogram, and substituting the secondary integration area into the standard curve so as to obtain the free radical content N. The method provided by the invention can exactly measure free radical content in coal tar, meanwhile, the change of the content of the free radical in the coal tar along with the preservation condition is exactly measured, and the method for detecting ration is provided for the research of the free radical in the coal tar and is very simple and easy.

Embodiments of methods and apparatus use electron paramagnetic resonance spectroscopy to provide a signal from melanin to image a melanoma. Embodiments of methods and apparatus use electron paramagnetic resonance spectroscopy to provide a signal from melanin to detect metastatic melanoma in a sentinel lymph node. Embodiments of methods and apparatus use electron paramagnetic resonance spectroscopy to provide a signal from melanin to measure light penetration in melanocytes in skin.

The invention provides a polyphenol-based coordination polymer nano-particle which is prepared from polyphenol, ferric iron salt and polyethylene glycol-modified polyglutamic acid. The polyphenol, the ferric iron salt and the polyethylene glycol-modified polyglutamic acid are adopted and coordinated to prepare the polymer nano-particle; the polymer nano-particle has the advantages that the preparation is simple, the condition is mild, the operation is easy, the sources of raw materials are low-toxic or non-toxic, and the price is low. The prepared coordination polymer nano-particle has a long circulatory function; the particle size ranges from 80nm to 110nm, the polymer nano-particle has an appropriate nano size, an EPR (electron paramagnetic resonance) effect can be realized, and accumulation can be realized in a tumor area. The polymer nano-particle has a dual mode imaging function, i.e., photoacoustic imaging and magnetic resonance imaging; the polymer nano-particle can be used for performing accurate photothermal therapy under the guidance of imaging.

The instant invention provides in-vivo methods and apparatus for radiation dosimetry assessment in individuals exposed to potentially harmful radiation, based on measurements in-situ of the teeth. The in vivo dosimetry assessment methods and apparatus utilize electron paramagnetic resonance (EPR) techniques; and employ an apparatus comprising an integrated EPR spectrometer system, an ergonomic magnet and a constructed resonator structure. In various aspects, the dosimetry assessment apparatus is configured to be easily portable and withstand potentially adverse mechanical effects of transportation and deployment in the field. The apparatus also is configured with a power supply that is compatible with both conventional AC line voltages and/or other sources of power suitable for field conditions; and may be easily operated by minimally trained technicians to quickly generate a readout of estimated radiation exposure dose.

The present invention relates to one kind of electronic paramagnetic resonance measurement scheme of personal radiation dose. It adopts horizontal working magnetic field and x band microwave work frequency, and during detection, magnetic poles of magnet are made to clamp the testee's face across the gum and the upper teech bite into rectangular detection hole in the front end cap of the resonant cavity. This mode ensures the relatively high detection sensitivity. The oral cavity area is held in relatively small magnet and this reaches high homogeneity of magnetic field and high working efficiency of magnetic field. The measurement method is practical.

The invention provides a novel stainless steel submerged-arc welding wire for improving tensile strength after heat treatment, belonging to the technical field of stainless steel welding wires for submerged-arc welding. The stainless steel welding wire provided by the invention comprises the following chemical components in percentage by weight: not more than 0.025 percent of C, not more than 0.60 percent of Si, 1.00-2.50 percent of Mn, not more than 0.02 percent of S, not more than 0.02 percent of P, 19.00-22.00 percent of Cr, 0.00-11.00 percent of Ni, not more than 0.50 percent of Mo, not more than 0.20 percent of Co, 0.07-0.20 percent of N and the balance of Fe. The welding wire benefits the solution to the technical problem that the tensile strength of the deposited metal, generated after tailor-welding heat treatment is carried out on a reactor end socket, is not in accordance to design requirements. The welding wire in the invention is mainly used for the tailor welding of end socket materials of an EPR (Electron Paramagnetic Resonance) nuclear power machine set and the welding of other materials.

The invention discloses a method for measuring superoxide anion radicals in tape grass leaves, belonging to the measuring field of the measuring of superoxide anion radicals. The method comprises the following steps of: firstly, collecting and cleaning the tip parts of fully exposed small and tender tape grass leaves; carrying out Tiron captureing on the Tiron of radicals in a closed operation box in a closed nitrogen environment; and finally measuring by using an EPR (Electron Paramagnetic Resonance) technology. The invention has the advantages of simpler operation and easy grasping, and can measure the superoxide anion radicals of the tape grass leaves in a very short time;, find that and the measured radicals are found to be the superoxide anion radicals according to the superfine structure constant and, the spectrogram shape analysis of an EPR spectrogram and the combination of the remarkable decreases of the radical strength of the leaves pretreated by SOD (Super Oxide Dismutase), and therefore the invention is the most direct, accurate and effective method for measuring the superoxide anion radicals. Superoxide anions are sensitive to pollutants and have a favorable dosage effect relation. The invention is also suitable for other aquatic plant and terrestrial plant species and can be suitable for measuring the radicals of the plant root tissue.

The invention provides an automatic frequency controller which comprises a frequency setting module and a frequency correcting module, wherein the frequency setting module is used for setting the frequency of a first wave source signal, and the frequency correcting module is used for correcting the frequency to the chamber resonant frequency. In this way, frequency setting and frequency correction functions are separated from each other. Under frequency separation conditions, the frequency setting module and the frequency correcting module can select sensitivity freely. Since the amplitude of signals generated in a signal generation module is low when the sensitivity of the frequency correcting module is high, the signal-to-noise ratio of the first wave source signal output by the automatic frequency controller is low. The frequency correcting module in the automatic frequency controller can select a device with low sensitivity to increase the amplitude of signals generated in the signal generation module. The signal-to-noise ratio of the first wave source signal output by the automatic frequency controller is thus increased. When the signal-to-noise ratio of the first wave source signal output is increased, the signal-to-noise ratio and sensitivity of corresponding electron paramagnetic resonance spectrometer are increased.

The invention relates to a drainage oil detecting method. Free radicals in an oil product are detected by using an electronic paramagnetic resonance wave spectrometer, and whether the oil product is drainage oil or whether drainage oil is doped in the oil product is judged by comparing the variation trend of the quantity of free radicals before and after temperature change. The method for in-situ test of a sample is wide in applicability, has a good detection effect on various oil products, and can be used for directly detecting whether the drainage oil is doped in the edible oil products.

The invention discloses an isoindole nitrogen oxide free radical modified polypyrrole and a preparation method and an application thereof. 3- and 4-site side groups in pyrrole repeating structural units of a polypyrrole high molecular material are chemically modified by an isoindole nitrogen oxide free radical derivative to obtain the product. Or 3- and 4-site side groups of pyrrole monomers are chemically modified by the isoindole nitrogen oxide free radical derivative, and then a polymerization reaction is carried out to obtain the product. Compared with polypyrrole, the modified polypyrrole has better electrical conductivity, higher charge storage density, better capacitance retention rate, fast electrode reaction dynamics performance, and oxidation-reduction ability and characteristic three-line electron paramagnetic resonance spectra similar to isoindole free radicals; the polymer has good rate capability and cycle stability in the processes of charging and discharging; and after 500-cycle charging and discharging circulation, the coulomb efficiency can be still kept at 95% or more, and the modified polypyrrole is expected to become a novel high-capacity and high-power battery material.

The invention discloses a hyaluronic acid-modified silicon-encapsulated drug-loading phospholipid liquid fluorocarbon nanosphere ultrasonic contrast agent and a preparation method thereof. The hyaluronic acid modified silicon-encapsulated drug-loading phospholipid liquid fluorocarbon nanosphere ultrasonic contrast agent prepared through an emulsification-silicon precipitation method has the particle size of approximately 274.5nm; the passive targeting can be realized through an EPR (Electron Paramagnetic Resonance) effect of a tumor site. Meanwhile, modifying hyaluronic acid can be also used for realizing the active targeting on a tumor cell; thus, the toxic and side effects of a preparation can be decreased; the curative effect of a drug is enhanced. On the other hand, compared with a phospholipid liquid fluorocarbon nanosphere, a hyaluronic acid modified silicon-encapsulated drug-loading phospholipid liquid fluorocarbon nanosphere prepared by the method has favorable stability and a lasting ultrasonic contrast effect. The hyaluronic acid modified silicon-encapsulated drug-loading phospholipid liquid fluorocarbon nanosphere ultrasonic contrast agent has the advantages of simple and convenient process, good biocompatibility of used materials, no use of a toxic surfactant, and wide application prospect.

The invention discloses an apigenin-carrying hyaluronic acid targeted nano assembly and a preparation method thereof. The system is composed of hydrophilic polysaccharide sodium hyaluronate and a hydrophobic drug namely apigenin. During preparation, firstly, sodium hyaluronate and apigenin powder are fully ground in a grinding bowl; then, the mixed powder is taken to mix with distilled water, and a primary nano suspension is obtained by stirring; and finally, ultrasonic treatment is performed with an ultrasonic cell crusher to obtain the apigenin-carrying hyaluronic acid targeted nano assembly. The drug carrier system disclosed by the invention significantly improves the dissolution rate of a drug and has good physical stability. The other outstanding advantage of the drug carrier system is that the particle size is small, the average particle size is less than 200nm, and passive targeting can be realized by virtue of an EPR (electron paramagnetic resonance) effect of a tumor location. Meanwhile, hyaluronic acid is taken as a carrier, so that the apigenin-carrying hyaluronic acid targeted nano assembly can realize active targeting, reduce toxic and side effects, and improve the treatment efficiency of an antitumor drug.

The invention relates to a method for detecting the influence of electron beam irradiation on free radical concentration of coal by virtue of electron paramagnetic resonance. The method comprises the following experiment steps: (1) carrying out pretreatment on a coal sample; (2) irradiating the coal sample by electron beams of different doses; and (3) carrying out ESR (electron spin resonance) analysis on the coal sample before and after electron beam irradiation. By carrying out electron beam irradiation on the coal sample subjected to pretreatment, the coal sample with different irradiation doses can be obtained by controlling an electron accelerator. Then, analysis on Lande g factor, free radical concentration Ng, peak width delta H and peak height Hpp is carried out on the coal sample before and after electron beam irradiation so as to research the change of a coal structure. The method has the advantages that the operation is relatively simple and easy to master, the change of the free radical concentration of the coal can be measured in short time, and a good dose effect relation can be achieved, thereby laying a foundation for further research on a coal macromolecular structure.

In a method of annealing a storage phosphor screen comprising a photostimulable phosphor by adding energy in form of heat and/or radiation, said method is applied during a time and in relative humidity conditions such that said phosphor shows peaks in an electron paramagnetic resonance (EPR) spectrum measured at a frequency of 34 GHz, at flux densities of magnetic fields of 880 mT, 1380 mT and 1420 mT, wherein said peaks exceed normalized signal intensity percentages of at least 45% and even of at least 55%, wherein a central peak height in the said EPR-spectrum, measured at a magnetic flux density of 1220 mT, is calculated to have a normalized value of 100%.

The invention relates to a probe capable of carrying out electron paramagnetic resonance (EPR) detection on an external sample. The probe is rectangular in both external shape and internal cavity, the mode of resonance is TE101, and the top face of the probe is provided with an open polygonal sample detection port. The detection port longitudinally penetrates into the space of the internal cavity along the wall thickness direction and runs through along the thickness direction of the probe. Long sides of the detection port are vertical to the direction of a microwave magnetic-field component of the internal cavity at the long sides and parallel to the direction of current lines on cavity walls at the long sides. A pair of coils providing modulation magnetic fields is placed at the two sides of the detection port, and modulation magnetic fields required for paramagnetic resonance are generated at the position of the detection port by the coils. A coupling and tuning unit carries out coupling by adopting a coupling diaphragm with a coupling hole and adjusts a coupling constant for the cavity and a microwave system by using adjusting bolts outside the coupling hole. The probe is mainly used for carrying out local detection on samples which are inconveniently sampled and made into samples.

The invention discloses an in-situ measurement method based on an electron paramagnetic resonance-magnetic resonance imaging three-dimensional magnetic field. The in-situ measurement method comprisesthe following steps: step 1, performing heating; step 2, performing polarization; step 3, performing electron paramagnetic resonance and magnetic resonance imaging; and step 4, performing three-dimensional magnetic field in-situ measurement. The method has the following beneficial effects: the measurement sensitivity and precision of the residual magnetic field measurement after passive magnetic shielding in the magnetic resonance imaging gyroscope are improved; a sensitive source of the measured magnetic field and a sensitive source for measuring angular motion are located in the same atomicair chamber and are real magnetic fields with nuclear spin feeling, the active magnetic compensation precision is improved and thus the zero-bias stability of the gyroscope is further improved; meanwhile, an atom magnetometer constructed based on the method can work in a geomagnetic field environment, high sensitivity and precision are realized, and the in-situ measurement method can be applied tothe fields of magnetic anomaly detection, geomagnetic navigation, deep space detection and the like.

The invention provides a method for in-situ and real-time detection of the concentration of hydrogen peroxide in living cells. The method comprises the following steps: carrying out electrochemical test to obtain the current-time curve of the living cells stimulated by a medicine, carrying out electron paramagnetic resonance wave spectrum test to obtain the ESR map of the living cells irradiated by ultraviolet lights in an electrochemical cell, and establishing an ESR signal intensity-current relation curve; and carrying out electron paramagnetic resonance wave spectrum test on a hydrogen peroxide standard solution to obtain the ESR map of the hydrogen peroxide standard solution irradiated by the ultraviolet lights, establishing an ESR signal intensity-hydrogen peroxide concentration standard curve, and synthesizing above three curves to obtain the concentration of hydrogen peroxide released by the stimulated living cells at any time in order to complete real-time detection of the concentration of hydrogen peroxide in the living cells. The method allows the quantitative detection of the concentration of the hydrogen peroxide released by the living cells to be accurate, can realize in-situ and real-time monitoring of the concentration of hydrogen peroxide released by living cells, and has wide application prospect.