7974 results about "Radiochemistry" patented technology

The invention discloses a processing method of a fusion device, and belongs to the technical field of nuclear fusion. The processing method comprises the following steps: carrying out at least one time of vacuum heat treatment on a Dewar embedded part blank; carrying out cleaning anti-corrosion treatment and physical correction treatment on the surface of the dewar embedded part blank subjected to heat treatment; carrying out grinding and polishing treatment on the surface of the Dewar embedded part blank subjected to the cleaning and antiseptic treatment and the physical correction treatment to obtain the Dewar embedded part; the Dewar embedded part is transported to the installation position of the window to be installed, and the Dewar embedded part located at the installation position is temporarily fixed; performing concrete pouring on the mounting position of the Dewar embedded part; and after the concrete is solidified, a cast-in-place concrete structural body is formed in the area below the Dewar embedded part, and a part of the Dewar embedded part is embedded into the cast-in-place concrete structural body. By means of the method, the magnetic conductivity of the Dewar embedded part is reduced, and the risk that elements are activated to form isotopes with the long decay period and the high irradiation dose rate or isotopes with the short decay period and the high irradiation dose rate is reduced.

The present application relates to the field of nuclear reactor simulation. Disclosed are a fast simulation method and system for multi-physical field coupling and a storage medium. The method comprises: at intervals of a first preset interval time, collecting state information of each physical field of a nuclear reactor in a transient process, so as to obtain physical field snapshots of a plurality of physical fields, the transient process being simulated by a reactor simulation model corresponding to the nuclear reactor; stitching the physical field snapshots of the plurality of physical fields, so as to obtain a fully-concatenated physical field; constructing a matrix on the basis of the fully-concatenated physical field; performing order reduction processing on the matrix, so as to construct a timing model corresponding to the fully-concatenated physical field; and decomposing the timing model corresponding to the fully-concatenated physical field, so as to obtain timing models corresponding to the plurality of physical fields. The fast simulation method for multi-physical field coupling of the present application can reduce the inconsistency between different physical fields while increasing the computation speed.

The invention relates to the technical field of isotope production, in particular to a welding-free target capsule for isotope production and a manufacturing method of the welding-free target capsule. The welding-free target capsule comprises a target material used for generating isotopes under bombardment of high-energy particles; the first metal film covers one side of the target material; the second metal film covers the other side of the target material; wherein the first metal film and the second metal film are made of materials with ductility; the edge of the first metal film and the edge of the second metal film are attached to each other on the peripheral side of the target material and are folded into an annular sealing structure. In the invention, the metal film with good ductility is used as a coating material of the target material, and the sealing structure is formed by folding the connecting part of the metal film, so that the target capsule can be ensured to efficiently dissipate heat in a water-cooling environment, the manufacturing mode of the sealing structure can be improved, the manufacturing steps of the sealing structure are simple and easy to implement, and the manufacturing cost of the target capsule is further reduced.

The invention discloses a method and tool for manufacturing a cold shield of a nuclear fusion device, and relates to the technical field of metal plate machining. The manufacturing method of the cold shield of the nuclear fusion device comprises the following steps: providing a sub-panel, a flange and a pipe fitting; the multiple sub-panels are welded, and a first middleware is obtained; welding the edge of the first middleware and the turnup to obtain a second middleware; after the pipe fitting is welded to the surface of the second middleware, a third middleware is obtained; and the third middleware is shaped. According to the method, the third middleware is shaped, that is, the third middleware is shaped after all welding procedures are completed, so that the third middleware has relatively small profile tolerance, the profile tolerance of the cold shield meets the design requirement, the assembly difficulty of the cold shield is reduced, and the risk of failure of the cold shield is reduced.

The invention relates to the technical field of scintillator materials and X-ray detection, in particular to a rare earth organic-inorganic hybrid complex scintillator and a preparation method and application thereof. The general formula of the rare earth organic-inorganic hybrid complex scintillator is [RE (L) 4] <->. [A] < + >, wherein RE is selected from Eu, Tb, Sm or Dy; l is a beta-diketone ligand; [A] < + > is selected from long-chain hydrophobic quaternary ammonium salt cations or heterocyclic quaternary ammonium cations which have the carbon atom number of C8-C20 and do not contain active functional groups. The rare earth organic-inorganic hybrid complex scintillator provided by the invention has good solubility and molecular-level dispersion capability. The scintillator film based on the rare earth organic-inorganic hybrid complex prepared by using the rare earth organic-inorganic hybrid complex has the characteristic of compatibility of high scintillator load and high light transmission, overcomes the problems of low scintillator load rate, poor transparency and limited imaging resolution of the traditional scintillator film, and has excellent practical value and popularization prospect.

The invention discloses an ocean in-situ radioactivity monitoring method, which is characterized in that feature extraction is carried out based on a maximum likelihood expected value maximization (MLEM) algorithm, and spectrum unfolding operation is carried out by adopting a multi-layer perceptron. The method comprises the following steps: firstly, measuring FWHM related parameters of a CeBr3 detector by adopting a standard source, simulating the response of the detector to gamma rays in a marine environment based on a Monte Carlo method, and establishing a full-spectrum response matrix H in a range of 0-2048keV; based on the response matrix H, reconstructing a gamma energy spectrum y obtained by the detector by using an MLEM iterative algorithm; and the reconstructed spectrum is used as the input of a multi-layer perceptron (MLP), and qualitative and quantitative analysis of radionuclides in the energy spectrum is realized. According to the method, the discrete characteristic peak signal is convolved into the single path address corresponding to the characteristic energy, so that the accuracy of the MLP model in the spectrum unfolding process is effectively improved.

A point of care analyte detection and quantification system for healthcare application is provided. Related methods are also provided.

The invention relates to the field of reactor data processing, and particularly discloses a numerical calculation method for solving a neutron transport equation. The method comprises the following steps: 1, describing the geometry of a reactor core of a nuclear reactor by utilizing a construction entity geometric modeling method, and subdividing a curved surface grid along a curved surface structure; 2, directly expanding a neutron flux distribution function in each curved surface grid by using a multivariate polynomial; 3, deriving a neutron transport equation and an integral residual equation of a boundary condition under each curved surface grid; 4, solving geometric integral parameters of each curved surface grid; step 5, establishing an adaptive linear system; and step 6, iteratively calculating and solving a maximum characteristic value and an unknown expansion coefficient.

The invention discloses a BNCT dose calculation method, which comprises the following steps: S1, constructing a voxel model, initializing one or more particles in a simulation system, and respectively acquiring the initial position, energy and movement direction of each particle; s2, adaptively selecting a Monte Carlo particle tracking algorithm and a flux counting mode based on the region where the particles are located and the energy of the particles; s3, repeating the step S2 until the particles leave the simulation system or are killed when meeting a truncation condition; and S4, cumulatively calculating dose distribution. Through the BNCT dose calculation method, the Monte Carlo particle transport simulation time is greatly shortened, the BNCT dose calculation efficiency is optimized, and the method is suitable for rapid and high-precision radiation dose simulation under a BNCT complex tissue structure.

The invention relates to the technical field of gamma-ray spectrum analysis, particularly provides a gamma-ray detector activation analysis method and a PGNAA detection system, and aims to solve the problems that gamma rays obtained by detection of an existing gamma-ray detector comprise rays generated by decay of crystals after activation in a neutron field; therefore, the component detection result of the to-be-detected sample is not accurate. In order to achieve the purpose, the activation analysis method for the gamma detector comprises the steps that a to-be-detected sample is irradiated through a neutron source; repeatedly collecting a plurality of groups of gamma-ray energy spectrums of the sample to be detected by using a gamma-ray detector; constructing an energy spectrum signal matrix based on the gamma-ray energy spectrum of the to-be-detected sample, wherein the energy spectrum signal matrix is a mixed signal composed of instant gamma rays generated by neutron activation of the to-be-detected sample, environmental background gamma rays and interference signals generated by crystal activation in a gamma detector; and obtaining the effective instant gamma ray based on the energy spectrum signal matrix. The self-interference influence of the detector is effectively reduced, and the target element content evaluation precision of the to-be-detected object is improved.

The invention provides a samarium / europium / gadolinium-containing zirconium hydride block as well as a preparation method and application thereof, and relates to the technical field of radiation shielding materials. The zirconium hydride block containing samarium / europium / gadolinium comprises the following elements in percentage by mass: 95% < = Zr < = 99.5%, 0% < = Gd < = 5%, 0% < = Sm < = 5%, 0% < = Eu < = 5% and 0% lt. Gd + Sm + Eu < = 5%. The preparation method comprises the following steps: respectively hydrogenating sponge zirconium, metal gadolinium, metal europium and metal samarium to respectively obtain corresponding hydride powder; weighing zirconium hydride powder, gadolinium hydride powder, europium hydride powder and samarium hydride powder according to a required proportion, and uniformly mixing under a protective atmosphere; and carrying out pressure sintering on the mixed powder, and carrying out secondary hydrogenation to obtain the zirconium hydride block containing samarium / europium / gadolinium. According to the invention, the absorption of the material to low-energy-segment neutrons can be obviously improved; and the preparation of the zirconium hydride block containing samarium / europium / gadolinium and the accurate regulation and control of doped elements are realized.

The invention relates to the technical field of Tokamak nuclear fusion, and discloses an assembling method of a pre-assembled assembly of a nuclear fusion device and an installing method of the nuclear fusion device. The pre-assembled assembly comprises a vacuum chamber, a window neck tube in the vacuum chamber, a vacuum chamber cold shield and a TF magnet; the assembling method of the nuclear fusion device preassembled assembly comprises the following steps: supporting between a cold shield inner sector and a vacuum chamber through a first tool; a first tool is supported between the cold shield outer sector and the vacuum chamber; the TF magnet is connected with the middle window position of the vacuum chamber through a second tool, the upper arc-shaped section of the outer fan section of the cold shield is connected with the hoisting tool of the TF magnet through a third tool, and the lower window section of the outer fan section of the cold shield is connected with the second tool; and the middle window section and the annular field magnet supporting seat are connected through a fourth tool. According to the assembling method of the nuclear fusion device pre-assembled assembly, interference among installation of the vacuum chamber, the window neck tube in the vacuum chamber, the vacuum chamber cold shield and the TF magnet can be avoided, and the stability and functionality of the pre-assembled assembly structure are guaranteed.

A compound or molecular complex. The compound or molecular complex comprises: a metal chelator configured for chelation with a radioactive isotope or a non-radioactive isotope; and a trifluoroborate (BF3)-containing moiety configured for 19F / 18F exchange or a precursor thereof; and optionally a cell-targeting domain.

The present application discloses a method and system for identifying internal surface defects of a nuclear reactor pressure vessel, a computer device, and a computer-readable storage medium. The method comprises: collecting image data of the surface of a pressure vessel; constructing an illumination angle attention mechanism, using an image in a data set to establish a feature map, and producing a spatial attention map on the basis of a spatial relationship of the feature map; and using the illumination angle attention mechanism to improve a YOLOv5 model, and identifying surface defects of the pressure vessel by means of the improved YOLOv5. The present application has the characteristics of high defect identification efficiency, low missed detection rate, etc. The present application can effectively cope with common problems when defect detection is performed under different illumination conditions. This precise defect localization and identification capability is critical for ensuring safe operation of pressure vessels, particularly during routine maintenance and inspection.

The invention provides a liquid cooling impurity monitoring method and system, and the method comprises the steps: obtaining an existing liquid cooling impurity attribute set through spectral analysis and microscopic imaging, deploying an impurity detection module in a liquid cooling channel, and obtaining a resonance spectrogram of the liquid cooling channel and environment parameters of the liquid cooling channel; performing cooperative feature extraction on the liquid-cooling cold channel resonance spectrogram and the liquid-cooling cold channel environment data, generating a liquid-cooling ecological vector, obtaining a historical liquid-cooling ecological vector corresponding to the historical data of the liquid-cooling cold channel, constructing a liquid-cooling impurity monitoring model, performing model pre-training to generate a liquid-cooling impurity library, inputting the liquid-cooling ecological vector to the liquid-cooling impurity monitoring model, and obtaining a liquid-cooling impurity monitoring result. Performing liquid cooling impurity matching on the liquid cooling ecological vector and a liquid cooling impurity library based on a cuckoo algorithm to obtain a liquid cooling impurity combination vector, obtaining a pre-trained impurity purification decision model, inputting the liquid cooling impurity combination vector into the impurity purification decision model, and generating an optimal liquid cooling impurity purification strategy, and a user can perform impurity removal on the liquid cooling system according to the optimal liquid cooling purification strategy.

A positron emission tomography (PET) scanner includes a plurality of gamma radiation detector modules arranged to form a detector ring. Each detector module includes an array of scintillator detectors. Each scintillator detector comprises a monolithic scintillation crystal and a plurality of photodetector arrays, such as silicon photomultipliers (SiPMs). A photodetector array is positioned on at least two nonparallel faces of each scintillation crystal. In some examples, a photodetector array is positioned on each of three orthogonal faces of each scintillation crystal.

Carriers for embodying radioactive seeds, as well as a device for loading and customizing brachytherapy carriers based on the principles of optimizing a more precise and predictable dosimetry, and adaptable to the geometric challenges of a tumor bed in a real-time setting. The present disclosure relates to a specialized loading device designed to enable a medical team to create a radionuclide carrier for each patient and tumor reliably, reproducibly and efficiently.

The invention relates to the technical field of CLYC neutron-gamma rays, and provides a CLYC neutron-gamma ray screening detection method and device based on deep learning, and the method comprises the steps: carrying out the preprocessing of an original pulse waveform outputted by a CLYC detector, and obtaining clean standard waveform data; constructing a one-dimensional convolutional neural network model, respectively capturing the features of the waveform at different time scales, and identifying the most discriminative feature region in the waveform through an attention mechanism; performing adaptive adjustment on the original hyper-parameter of the one-dimensional convolutional neural network model to obtain an optimized hyper-parameter; establishing a direct mapping relation from an original pulse waveform to a neutron-gamma particle type to obtain a trained model; and carrying out compression optimization processing on the model, and deploying the model to an embedded platform to carry out neutron-gamma ray discrimination. According to the method, automatic extraction of deep discrimination features of the CLYC pulse waveform and accurate identification of key feature areas are realized, and the discrimination accuracy and noise interference resistance of neutron-gamma rays are improved.

The invention relates to the technical field of safety monitoring of a nuclear reactor, and particularly discloses a multi-region pressure overrun leakage monitoring method for a reactor pressure vessel. The method comprises the steps of multi-region pressure data acquisition, real-time pressure field model construction, dynamic pressure field baseline modeling, pressure overrun anomaly detection, leakage source accurate positioning and evaluation based on spatial gradient analysis, topological structure mapping and multi-sensor data fusion, and graded early warning and response. By the adoption of the technical scheme, real-time and fine monitoring of pressure distribution in the reactor pressure vessel can be achieved, the rapid and accurate judgment and positioning capacity of leakage events is improved, the operation safety and reliability of nuclear power facilities are enhanced, and the reliability of the nuclear power facilities is improved. The defects of independent monitoring, local accurate positioning and complex working condition adaptability of multi-region pressure over-limit leakage in the prior art are overcome.

Main characteristic of the invention is the exploitation of the very large flux of high energy neutrons generated in a nuclear fusion tokamak with beam-driven plasma for the purpose of producing radioisotopes. It specifically relates to the deployment of precursor materials into the core of a nuclear fusion tokamak with beam-driven plasma for the purpose of exposing these materials to the neutron flux generated in the plasma by the process of nuclear fusion of Deuterium (D) and Tritium (T) to generate radioactive isotopes, so-called radioisotopes. The precursor materials contained in metallic capsules are incorporated into the blankets that surround the plasma.

The invention discloses an ion source automatic beam adjusting method, a radiotherapy system and related equipment, and relates to the technical field of radiotherapy, and the method comprises the steps: monitoring and adjusting a plurality of control parameters in real time, and obtaining an optimal control parameter combination; under the optimal control parameter combination, the variable quantity of each control parameter before and after adjustment and the performance change of the proton beam are obtained; performing a pulse width charge test according to the variation of each parameter before and after adjustment and the performance change of the proton beam; obtaining an optimal adjustment parameter and an adjustment amount through a pulse width charge test result; and through the optimal adjustment parameter and adjustment amount, automatic beam adjustment is realized, stable and efficient acceleration of the proton beam in the synchrocyclotron system is realized, and the stability and consistency of the proton beam are ensured.

The invention discloses a hybrid neutron gamma detector array and a signal processing method, and relates to the technical field of nuclear physical detection.During detection, eight EJ200 scintillators arranged in an array are used for energy deposition of gamma rays and fast neutrons and generating photons, and meanwhile three EJ426 thermal neutron scintillation screens are used for capturing thermal neutrons and generating photons; the response of gamma rays, fast neutrons and thermal neutrons is realized at the same time, and the detection precision is greatly improved. Meanwhile, if the three EJ426 thermal neutron scintillation screens are alternately stacked front and back, the total reflection of the EJ200 scintillators and the semi-light-proof performance of the EJ426 thermal neutron scintillation screens are utilized to block photon propagation in the X direction and only enable photons to be propagated in the Y direction and the Z direction, and each EJ200 scintillator corresponds to a four-channel photon collection structure to perform high-efficiency collection of the photons, so that the high-efficiency collection of the photons is realized. Therefore, high-precision detection and high-efficiency photon collection are realized, and support is provided for subsequent intense radiation field monitoring or high-precision positioning.

The invention provides a mineralogical substance composition testing method and system based on multispectral data fusion. The method comprises the following steps: separating out a first characteristic interference signal caused by the oxidation state of an iron element and a second characteristic interference signal caused by the oxidation state of a manganese element by adopting wavelet transform in a superposition region of a Raman spectrum signal and a visible light absorption spectrum; performing spatial weighting on the intensity of the first feature interference signal and the intensity of the second feature interference signal to construct a multi-dimensional feature vector, inputting the multi-dimensional feature vector to a pre-trained residual neural network, and combining a radioactivity attenuation parameter measured by a gamma spectrometer to determine the radioactivity attenuation of the first feature interference signal and the second feature interference signal. And generating a mineralogical substance composition test result containing a mineral phase, an isomorphic substitution ratio, color cause analysis data and a radiation safety level. According to the method, the collaborative interpretation of the multispectral data and the radiation parameters can be realized, the mineral component analysis precision is improved, the color formation mechanism is synchronously analyzed, and the radioactive risk level is quantitatively evaluated.

The invention provides a pencil beam dose calculation method. The pencil beam dose calculation method comprises the following steps: acquiring human body image data; determining a plurality of particle types for treatment; calculating initial pencil beam dose distribution corresponding to each particle type; based on the particle types, target action layers, distributed in the human body image data, of all the doses are determined, and the positions of the target action layers corresponding to different particle types are different; based on the target action layer corresponding to each particle type, adjusting each initial dose distribution, and obtaining particle pencil beam dose distribution corresponding to each particle type; superposing the particle pencil beam dose distribution corresponding to each particle type to obtain target pencil beam dose distribution; wherein the dose proportion of the particle pencil beam dose distribution corresponding to the same particle type in the target action layer is greater than the dose proportion of the particle pencil beam dose of the particle type in other parts in the human body image data.

The invention discloses a method for selecting and triggering gamma instant radiation pulse events, and belongs to the technical field of nuclear radiation detection. The method comprises the following steps: carrying out normalization preprocessing on an original gamma pulse radiation time spectrum; s time-frequency transformation is carried out on the preprocessed data, and time-frequency features are extracted; optimizing parameters of the frequency threshold and the amplitude threshold after S time-frequency transformation by adopting a deep reinforcement learning model to obtain an optimal frequency threshold and an optimal amplitude threshold; performing filtering processing on the signal of the S time-frequency conversion result, and separating noise from an effective signal; and searching a pulse radiation event for the filtered signal by applying a morphology-based peak searching method, and positioning the position and the characteristic of a real gamma instant radiation pulse event. According to the method, time-frequency analysis is carried out through S time-frequency transformation, the problem that the frequency of an analysis window cannot be adjusted through short-time window Fourier transformation is solved, the method has better frequency resolution and phase retention characteristics, and gamma pulse signal characteristics can be represented more accurately.

The invention discloses a fast thermal neutron and gamma ray multi-mode detector, and relates to the technical field of nuclear radiation detection, and the detector comprises a detector housing, and the interior of the detector housing is connected with a fast neutron detection unit, a thermal neutron detection unit and a gamma ray detection unit. The gamma ray detection unit is located between the fast neutron detection unit and the thermal neutron detection unit; and an insulating separation unit is connected between two adjacent detection units. The detector can detect fast neutrons, thermal neutrons and gamma rays in the same equipment at the same time, structures such as a cadmium thermal neutron shielding layer and a fast neutron moderation layer do not need to be added, the size of the detector can be greatly reduced, and the detector has the advantages of being compact in structure, stable in performance, wide in energy measurement range, wide in fluence rate measurement range and the like. The ultrahigh-energy high-flux neutron measurement with the neutron energy at least covering # imgabs0 # and the neutron fluence rate at least covering # imgabs1 # can be realized.

The invention provides a beam control system for BNCT treatment. The system comprises a treatment control module, an accelerator control module and a flux monitoring module. The treatment control module is used for acquiring the delivery dose and the delivery time of the BCNT in real time so as to trigger a beam stopping instruction based on the delivery dose or the delivery time, and transmitting the beam stopping instruction to the accelerator control module so as to terminate neutron beam delivery; the accelerator control module is used for receiving a beam stop instruction to correspondingly close the proton beam so as to terminate neutron beam delivery, and automatically close the proton beam when an abnormal condition occurs; the flux monitoring module is used for monitoring neutron flux in real time and transmitting monitoring data to the treatment control module so that the treatment control module can obtain the delivery dosage in real time based on the monitoring data. According to the application, the delivery of the beam is accurately controlled and the delivery dose and the delivery time are monitored in real time in the BNCT treatment process, so that the accuracy and the safety of the beam delivery of the equipment are ensured.

The invention provides an off-site full-range radiation risk evaluation method and system under a severe accident of a nuclear power plant, and the method comprises the steps: S1, building a radioactive accident risk evaluation basic model architecture, adapting to a model demand, and building a corresponding basic database; s2, constructing radioactive smoke plume characteristics after the accident; s3, calculating accident site space gridding and smoke plume transmission discretization; s4, sampling meteorological conditions, and simulating smoke plume transmission; s5, calculating the radiation dose in the early stage of the grid domain, and carrying out risk assessment; s6, performing risk assessment on the health effect in the early stage of the grid domain; s7, calculating the medium-and-long-term stage radiation dose in the grid domain, and performing dose risk assessment; and S8, performing health effect risk assessment and accident consequence assessment in the medium-and-long-term stage. According to the method, the whole transportation process of the radioactive smoke plume under a serious accident is simulated, loss effects such as dry and wet settlement and radioactive decay of the smoke plume are considered, and the activity of the radionuclide deposited on the ground and retained in the air in the off-site space range is determined.

In the case of forming a fine resist pattern, it is desired to further reduce the roughness of the resist pattern.SOLUTION: A substrate processing apparatus comprising: a heat treatment unit configured to bake a resist film; an exposure unit configured to irradiate the resist film having a portion irradiated with a first radioactive ray with a second radioactive ray; a development unit configured to form a resist pattern by development for removing a part of the resist film; and a control unit configured to control the exposure unit such that the second radioactive ray is collectively irradiated to an entire region of the resist film including the portion irradiated with the first radioactive ray and a portion other than the portion irradiated with the first radioactive ray. The first radiation is ionizing radiation or non-ionizing radiation, and the second radiation is non-ionizing radiation. When the first radiation is non-ionizing radiation, the second radiation is non-ionizing radiation having a wavelength longer than the wavelength of the first radiation. The resist film includes a metal oxide photoresist material.SELECTED DRAWING: Figure 1

A radioisotope production capsule is described. Each capsule includes generally an inner container for housing one of a target material and a neutron moderator, an outer container surrounding the inner container for housing the one of the target material and the neutron moderator not housed by the inner container, and cladding for isolating the target material from the neutron moderator. One or more modular capsules are placed in each of a plurality of plug fingers. Each single plug finger loaded with one or more capsules is inserted into a guide thimble of an array of guide thimbles in a fuel assembly.