240 results about "Neutron source" patented technology

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 relates to the technical field of radiation therapy, in particular to a boron neutron capture therapy beam shaping device and a boron neutron capture therapy system. The beam shaping device for boron neutron capture therapy is used for beam shaping of a DT neutron tube generator. The interior of the beam shaping device is provided with a particle beam channel, and the particle beam channel is used for generating an initial neutron source through an incident proton beam. The beam shaping device comprises a value-added layer, a moderator, a filter layer, a reflecting layer, a collimator and a shielding layer, wherein the value-added layer, the moderator, the filter layer and the collimator are sequentially arranged from a target material to an outlet. And the axes of the particle beam channel, the value-added layer, the moderator and the collimator coincide. According to the beam shaping device, 14Mev high-energy neutrons from the DT neutron tube generator are shaped into hot / slow neutron beams meeting the BNCT treatment requirements, and impurities of fast neutrons and gamma rays are reduced to the maximum extent, so that the dosage precision and biological selectivity of treatment are effectively improved.

Systems and methods for measuring the content of an element in a soil comprises: a neutron source for irradiating the soil with neutrons; a detector assembly configured to detect an INS gamma spectrum of the soil; an instrument for measuring a moisture content of the soil; and a processor in communication with the detector assembly, the processor configured to: apply a moisture calibration coefficient to calculate a net peak area of a characteristic peak of the element in the INS gamma spectrum, the moisture calibration coefficient calculated to account for the moderation of fast neutrons by hydrogen atoms of water present in the irradiated soil at the location under analysis; and generate a concentration of the element in the soil. The instrument for measuring a moisture content of the soil may comprise the detector assembly. Systems and methods incorporating a temperature-controlled housing for the gamma detector assembly are also provided.

The invention provides a device and a method for detecting residual stress and defects of a diaphragm by a neutron source. The device comprises a neutron source, a neutron detector, a diaphragm fixing assembly and a console, and the residual stress and defects of the diaphragm are nondestructively detected through a neutron diffraction technology. The diaphragm is fixed through the diaphragm fixing assembly, and the neutron beam of the neutron source is adjusted, so that the neutron beam completely covers the diaphragm; adjusting the angle of the diaphragm through the diaphragm fixing assembly, repeatedly recording stable diffraction signals to obtain multiple groups of strain data, and analyzing and processing to generate a residual stress nephogram and a defect distribution result. According to the scheme, accurate detection of residual stress and defects of the to-be-detected diaphragm is realized through the neutron diffraction technology, the method has the advantage of nondestructive detection, avoids damage to the diaphragm, is suitable for detection of various diaphragm materials, is accurate in measurement and simple and convenient to operate, reduces manual operation errors, and improves the detection accuracy. And meanwhile, the data is further analyzed and processed by utilizing cloud computing and a big data technology, so that the detection accuracy and efficiency are improved.

The invention relates to a neutron magnetic focusing device control system, and the system comprises a front-end sensing unit which is used for collecting the angle, temperature and other data of a neutron magnetic focusing device; the core control unit is used for realizing synchronous control and temperature protection of a motor and a neutron source T0 signal based on data acquired by the front-end sensing unit; the feedback compensation unit feeds back the equipment state in real time and dynamically compensates the phase deviation; the man-machine interaction unit supports local and remote dual-mode control; through cooperative work of multiple units, the system can realize high-precision synchronous control, real-time state monitoring and fault alarm, the operation stability and efficiency of a neutron magnetic focusing device are effectively improved, and reliable technical support is provided for a neutron scattering experiment.

A system includes one or more neutron sources configured to emit neutrons. The system also includes one or more electron detectors configured to detect electrons. Further, the system includes a control system comprising one or more processors. The control system is configured to determine a lithium concentration based on the electrons. Further, the control system is configured to generate a lithium extraction output based on the lithium concentration.

The invention discloses an accelerator neutron source solid-state lithium target cooling device, and relates to the technical field of accelerator neutron source medical application. An annular heat pipe is arranged on the outer ring of the side portion of an oxygen-free copper substrate, a plurality of liquid absorption cores are arranged on the inner wall of the heat pipe, and meanwhile an inner cavity of the heat pipe is filled with a working medium; when heat is generated, the heat is firstly transferred to the oxygen-free copper substrate, the evaporation section of the heat pipe is heated, the working medium in the wick is quickly evaporated and gasified, the generated steam flows to the condensation section under the driving of differential pressure and is condensed into liquid in the condensation section and releases heat, and the liquid generated by condensation returns to the evaporation section again under the capillary action of the wick. The space of the arranged heat pipe is large, and in the aspect of heat dissipation, the working medium is subjected to gas-liquid phase change in the heat pipe under the action of the liquid absorption core, so that the accelerator is rapidly dissipated, heat on the solid target material film can be rapidly taken away, and the cooling effect on the accelerator is greatly improved.

The invention belongs to the technical field of nuclear power plant subcritical degree determination, and particularly relates to a method for determining a subcritical degree by adopting a spatial effect of an external neutron source. Comprising the following steps: 1, obtaining a curve of the ratio of the subcritical degree to near-source and passive neutron detector signals through theoretical calculation; 2, obtaining measurement values of four source range neutron detectors and four intermediate range neutron detectors; 3, calculating a near-source and passive ratio; and 4, according to the ratio calculated in the step 3, searching a ratio curve of the subcritical degree and the signals of the near-source and passive neutron detectors so as to obtain the reactivity of the reactor core. The method has the beneficial effect that the subcritical degree cannot be obtained by directly measuring through an instrument when the power level of the reactor is lower. According to the method, the subcriticality can be quickly obtained in a chart form through the ratio of the near-source neutron detector signals to the passive neutron detector signals or the ratio of the passive neutron detector signals to the near-source neutron detector signals.

Embodiments of the present invention disclose a method, apparatus, device, and storage medium for determining neutron source intensity. The method includes: determining the source intensity of a primary neutron source as it changes over time after a reactor shutdown; determining the source intensity of a secondary neutron source as it changes over time after a reactor shutdown based on the determined thermal neutron flux density of a secondary neutron source; and determining the source intensity of a total neutron source as it changes over shutdown time based on the source intensity of the primary and secondary neutron sources, combined with predetermined spatial and energy spectrum factors, to ensure safe loading and startup of the unit. This method comprehensively considers the different locations and energy spectra of the primary and secondary neutron sources, which have different effects on the response of the off-core detectors, and combines the predetermined spatial and energy spectrum factors to determine the source intensity of the neutron source as it changes over time after a reactor shutdown, thereby achieving rapid and accurate determination of the neutron source intensity and providing a physical basis for reactor startup.

This invention relates to the field of neutron source technology, and particularly to a controllable isotope neutron source device based on ion migration and a method for generating neutrons. The device includes a casing, inside which are a target material module, a target ion migration system, a safety module, and an alpha particle source term. The target material module provides target nuclide ions. The alpha particle source term includes alpha radioactive nuclide material and target nuclide intercalation material. The safety module is composed of target nuclide intercalation material. The target ion migration system is connected to an external control field. Target nuclide ions migrate through the target ion migration system within the safety module and the alpha particle source term. This invention enables active controllability of the isotope neutron source, significantly improving safety. By ensuring sufficient contact between alpha particles and target nuclides to form a molecular intercalation structure, the (α,n) reaction efficiency is greatly improved. Furthermore, this neutron source can be used in combination with multiple modules according to application requirements, effectively increasing the neutron output flux.

The application relates to the technical field of medical data processing, and discloses a macroscopic cross-section database construction method, a dose determination method, a device and equipment, which comprises the following steps: setting multiple boron concentration values for the tissue types corresponding to a human body model; selecting corresponding neutron source parameters for the tissue types and the multiple boron concentration values, wherein the neutron source parameters comprise energy range values; dividing the energy range values into multiple discrete neutron energy groups; performing particle transport simulation based on the selected neutron source parameters, jumping between different neutron energy groups in the simulation process, and obtaining neutron reaction rates and neutron fluxes of the tissue types under the multiple boron concentration values and the multiple neutron energy groups; and obtaining neutron macroscopic cross-section values of the tissue types under the multiple boron concentration values and the multiple neutron energy groups based on the neutron reaction rates and the neutron fluxes, and constructing a multi-group macroscopic cross-section database. The application can improve the calculation efficiency of the radiation dose and improve the adaptability to individual metabolic differences during dose calculation.

The application discloses a GAN neural network multiple distortion suppression model based on a coordinate attention mechanism, obtains an original neutron radiographic image from a neutron source; proposes a brand-new neutron radiographic image degradation model; adds Gaussian blur, Gaussian noise, Poisson noise and noise obeying gamma distribution to the clear neutron radiographic image; uses real white spot noise to train the GAN neural network, simulates white spot noise and randomly adds the white spot noise to the clear neutron radiographic image; constructs a multiple distortion suppression model of the GAN neural network based on the coordinate attention mechanism; uses Huber loss to train the constructed GAN neural network based on the coordinate attention mechanism; inputs a real neutron radiographic image containing multiple distortions into the trained multiple distortion suppression model as input, predicts the original image of the real neutron radiographic image containing multiple distortions, and obtains a target result.

The invention relates to the technical field of medical data processing, and discloses a neutron source correction method and equipment for a radiotherapy planning system, and the method comprises the steps: obtaining a first value of a target physical quantity obtained based on physical experiment measurement, and obtaining a second value of the target physical quantity corresponding to the radiotherapy planning system; the physical experiment is used for quality guarantee; if it is determined that the deviation does not meet the preset requirement based on the first numerical value and the corresponding second numerical value of the target physical quantity, the target neutron input energy-angle spectrum is obtained through inversion by means of a regularization optimization model, so that the deviation meets the preset requirement; and correcting the neutron input energy-angle spectrum in the radiotherapy planning system based on the target neutron input energy-angle spectrum. According to the invention, the neutron input energy-angle spectrum in a radiotherapy planning system can be corrected, and the consistency of a simulation result and an experimental result is ensured, so that the requirement of boron neutron capture therapy on quality assurance is met.

The present application relates to the technical field of neutron source, and particularly provides a high-heat-carrying neutron target system, which aims to solve the problem of poor heat dissipation capacity of the neutron target system. To this end, the high-heat-carrying neutron target system comprises a base and a jet cylinder, the base comprises a first end portion and a second end portion; the jet cylinder is wrapped on the outer side of the base; and the high-heat-carrying neutron target system further comprises a turbulence structure, the turbulence structure comprises a first heat dissipation structure and a second heat dissipation structure for flowing cooling medium, the first heat dissipation structure is arranged on the base and penetrates through the base in the direction from the first end portion to the second end portion; and the second heat dissipation structure is arranged on the jet cylinder, the second heat dissipation structure is communicated with the first heat dissipation structure, and the cooling medium in the second heat dissipation structure flows into the first heat dissipation structure in a preset direction to form turbulence for the cooling medium in the first heat dissipation structure. In the present application, the second heat dissipation structure is used to effectively increase the turbulence degree of the cooling medium in the first heat dissipation structure, thereby greatly improving the heat exchange effect of the neutron target system.

The application provides a nuclear reactor first cycle starting method and device, an electronic device and a storage medium, and belongs to the technical field of nuclear power. The application obtains neutron intensity change data of a secondary neutron source assembly, the neutron intensity change data including time steps and neutron release intensity of the time steps, selects the smallest neutron release intensity from the neutron intensity change data as a target neutron intensity, obtains the time step of the target neutron intensity if the target neutron intensity is greater than or equal to a preset neutron intensity threshold, obtains a target time, determines a target reactor entry time period of the secondary neutron source assembly according to the target time and a pre-obtained reactor starting time of the target nuclear reactor, and performs first cycle starting on the target nuclear reactor according to the target reactor entry time period and the secondary neutron source assembly. The application can allocate appropriate reactor entry time for the secondary neutron source assembly, and realizes first cycle starting of the nuclear reactor using the secondary source assembly to replace the primary source.

The invention relates to the technical field of nondestructive testing of element content and uniformity of fuel elements, and provides a fuel element detection method and system based on neutron imaging and activation analysis. The detection method comprises the following steps: S1, installing a to-be-detected sample, and adjusting an imaging collimation hole to be aligned with a neutron beam current of a neutron source; s2, the thermal neutrons are collimated by the imaging collimation hole and then transmit the to-be-detected sample, and spatial distribution of uranium and poison elements of the to-be-detected sample is obtained through detection of a neutron imaging detector; s3, selecting a specific target area, switching the activation analysis collimation hole to align to a neutron beam of the neutron source, and adjusting the position of the to-be-detected sample, so that the specific target area aligns to the neutron beam of the neutron source; thermal neutrons bombard a specific target area after being collimated by the activation collimation hole, and are received by the gamma ray detector so as to analyze and obtain the element content of the specific target area. According to the method, distribution and content of uranium and toxic elements in the fuel element can be rapidly and accurately determined on the premise of nondestructive testing.

The invention discloses a neutron source assembly which comprises a neutron source rod body, a lower end plug, a composite upper end plug and a guide cylinder, and the neutron source rod body comprises a neutron source rod end plug, a neutron source rod cladding tube, an upper reflecting layer, a lower reflecting layer, a source box and a matched end plug. The neutron source assembly adopts the rod-in-rod design, the possibility of abrasion of the neutron source rod body in the transportation process and the like can be reduced, the neutron source leakage risk is reduced, the counterweight design of the composite upper end plug can counteract the buoyancy of a coolant in a reactor, and it is ensured that the neutron source assembly smoothly falls to the bottom and keeps stable; the neutron source rod body can be used in a pressurized water reactor and can also be used in a liquid heavy metal reactor. Meanwhile, the sealing packaging structure of the neutron source rod body can reduce the risk of neutron source leakage caused by abrasion in the transportation and in-reactor operation process, the arrangement of the guide cylinder provides guidance for the assembly of the neutron source rod body, and the probability of collision damage of the neutron source rod body in the assembly process is reduced.

The present invention provides a method, terminal, and medium for obtaining a target thickness of a hydrogen embrittlement-resistant layer of a neutron source target. The method includes: using a physical field fitting method to perform hydrogen diffusivity fitting based on deposition distribution and thermal performance fitting based on energy distribution on a target including a hydrogen embrittlement-resistant layer to obtain a hydrogen atom concentration distribution characteristic and a corresponding temperature distribution characteristic corresponding to the current thickness; detecting whether the hydrogen atom concentration distribution characteristic satisfies a predetermined condition for the hydrogen atom concentration field and whether the temperature distribution characteristic satisfies a predetermined condition for the temperature field; and, if both conditions are satisfied, setting the current thickness of the hydrogen embrittlement-resistant layer as the target thickness of the hydrogen embrittlement-resistant layer. This method makes it possible to quickly and easily obtain a target thickness of the hydrogen embrittlement-resistant layer that is compatible with the physical field performance of other layers in the target, thereby improving the hydrogen resistance performance of the target and effectively improving the overall performance of the target.

The present application relates to the technical field of neutron irradiation, and provides a neutron generating device, comprising a graphite stack, a neutron source, a shielding shell and a plurality of movable plates, wherein the graphite stack forms a radiation cavity and a detection cavity, the neutron source is arranged in the radiation cavity, the neutron beam emitted by the neutron source is moderated by the graphite stack to form thermal neutrons, and a thermal neutron reference radiation field is generated, the shielding shell forms a accommodating space, the graphite stack is arranged in the accommodating space, the shielding shell is provided with a plurality of beam ports connected to the accommodating space, the plurality of movable plates are movably connected to the shielding shell to selectively open or cover the beam ports, wherein the thermal neutron reference radiation field forms an inner calibration area and an outer calibration area, and detector traceability is achieved by placing a detector in the inner calibration area or the outer calibration area.

The invention discloses a nuclear rod power generation device, the nuclear rod power generation device comprises a nuclear fuel device, a neutron source device, a control assembly and a water pipe device, the nuclear fuel device is arranged in the water pipe device, and the water pipe device comprises a water inlet and a water outlet; the nuclear fuel device comprises an inner sleeve and an outer sleeve, the inner sleeve is arranged in the outer sleeve, the two ends of the inner sleeve and the two ends of the outer sleeve are connected in a sealed mode, a vacuum cavity is formed between the inner sleeve and the outer sleeve, and nuclear fuel coatings are arranged on the outer side of the inner sleeve and the inner side of the outer sleeve. The neutron source device is arranged on the inner side of the inner sleeve through a guide pipe, and the control assembly adjusts the position of the neutron source device in the guide pipe. The invention provides a nuclear rod power generation device which adopts a safe and miniaturized nuclear reaction technology and can replace a huge nuclear reactor.

A method for tracking the lunar regolith depth of the lunar surface neutron source based on particle transport analysis, comprising: obtaining the high-energy particle spectrum of the lunar surface; establishing a particle transport model; according to the high-energy particle spectrum and the particle transport model, emitting initial particles into the lunar regolith model, and forming events and tracks after interacting with the lunar regolith after entering the lunar regolith; first forming an initial trajectory record and transmitting it to the event record set; the neutron tracks are transported step by step, and the current event record is updated according to the property change of the neutrons caused by the interaction; the neutrons perform elastic collision motion in the lunar regolith, until the neutron transport ends, forming an end track record and transmitting it to the event record set; when all the events are transported, output all the information in the event record set; according to the high-energy particle spectrum statistics, obtain the lunar regolith depth from which neutrons of different energies on the lunar surface are sourced, providing a basis for the design of the drilling depth for water exploration on the lunar surface.

The invention provides a multi-detector PGNAA element interested interval analysis method, and relates to the technical field of gamma-ray spectrum analysis, and the method comprises the following steps: irradiating a sample by using a neutron source, and obtaining gamma-ray spectrum and neutron flux by using multiple detectors; analyzing the reference characteristic elements of the characteristic peaks, and determining the uniform or non-uniform state of the sample according to the counting standard deviation of the characteristic peaks; and subdividing types in a non-uniform state, dividing interested intervals, adjusting the position of a detector, correcting an energy spectrum, calculating a weighted count, and finally calculating an element detection lower limit. By means of multi-detector state judgment, interval division, energy spectrum correction and the like, accurate analysis of the element interested interval of the non-uniform sample is realized, the detection accuracy is improved, and the element detection lower limit is reduced.

Maintainability is to be improved. A radio frequency quadrupole linear accelerator includes a tubular housing part having an outer peripheral surface at which two pairs of openings extending in an axial direction are formed facing each other, and a plurality of first vane electrodes inserted into the respective openings of the tubular housing part from outside toward an axial center, detachably attached to the openings, and disposed facing each other.

The application provides a fuel and a method for increasing the neutron source intensity of a nuclear reactor, wherein the abundance of O in the fuel is 1% to 50% 18 O is 1% to 50%, and alpha particles and the enriched 18 O can significantly enhance the initial neutron source intensity of a nuclear reactor core in a pressurized water nuclear power plant, and help to improve the start-up performance and reduce the dependence on external neutron sources. In the passive start-up mode without using an external neutron source, the application improves the isotope abundance of O in the fuel, and improves the (alpha, n) reaction neutron source in the nuclear reactor core in the pressurized water nuclear power plant. 18 O in the fuel, and improves the isotope abundance of O in the fuel, and improves the (alpha, n) reaction neutron source in the nuclear reactor core in the pressurized water nuclear power plant.

The invention discloses a neutron beam real-time regulation and control method and system based on two parameters, and the method comprises the steps: collecting the two parameters and a target beam current in real time, and obtaining a data set; an LSTM-Attention initial model is constructed; training, verifying and testing the LSTM-Attention initial model by using the training set, the verification set and the test set to obtain a final neutron beam current control model; the deviation between the target beam current and a set value is monitored in real time, a final neutron beam control model is used for inversion to obtain a two-parameter adjusting quantity, and real-time neutron beam regulation and control are achieved; according to the method, the coupling relation between the two parameters and the beam is considered, the current and the air inflow of the ion source can be adjusted in real time, stable operation of the neutron source beam is ensured, the neutron yield stability is improved, and the application effect in practical application can be improved.

The invention discloses a high-thermal-conductivity solid target, which belongs to the technical field of accelerator neutron sources and comprises an insulating PEEK base and an integrated solid target. The integrated solid target is arranged on the insulating PEEK base, and a target body of the integrated solid target is tightly attached and fixed to the insulating PEEK base; a circular positioning groove is formed in the insulation PEEK base and used for fixing the initial position of the integrated solid target, a sealing ring clamping groove is formed in the circular positioning groove, and two water cooling channels are arranged in a base body below the positioning groove in a penetrating mode. The back of the target body of the integrated solid target is integrated with a plurality of groups of radiating fins and an inverted-cone-shaped groove right facing a deuterium beam, so that an efficient radiating channel is formed. According to the high-thermal-conductivity solid target, by arranging the inverted-cone-shaped grooves and the cooling fins, the heat exchange area of beams can be increased, the structural stability of the high-thermal-conductivity solid target can be enhanced, the thermal stress level can be reduced, and the structural integrity and long-term working reliability of the target material can be guaranteed.

The application discloses a mechanical arm for installing a radioactive source of a radioactive logging instrument, and relates to the technical field of low-carbon oil exploitation. The mechanical arm comprises a positioning base plate and a mechanical arm body fixed to the positioning base plate. An installation frame is rotationally connected to the mechanical arm body. The installation frame is provided with circumferentially distributed outlets. Part of the outlets are sealed by sealing blocks. The other part of the outlets is threadedly connected with installation rods. The installation rods are slidably connected with connecting rods. The installation frame, the installation rods and the connecting rods are all provided with cavities in communication. The outer ends of part of the connecting rods are provided with slip type grippers. The mechanical arm can automatically complete all processes from loosening a hexagonal nut, opening a can cover, clamping a neutron source, placing the neutron source into a storage body, closing a storage cover and tightening the nut, without manual intervention, frequent replacement or adjustment of tools, so that operation complexity is reduced, work efficiency is remarkably improved, and radiation exposure risk is reduced.

The present invention relates to a method of operating an MSR, said MSR comprising a reactor core, a fuel loop for molten fuel salt providing a flow path of molten fuel salt into the reactor core through a reactor core inlet and out of the reactor core through a reactor core outlet, said method comprising the steps of: providing at least one location mi on the fuel loop at a distance Li measured along the flow path from the reactor core outlet, wherein the one or more locations mi is outside the reactor core, and the one or more locations mi is shielded from the reactor core measuring the neutron source strength at the one or more locations mi obtaining one or more calculated operating parameters by calculation with input of the value of the measured neutron source strength at one or more locations mi.

The invention provides a self-repairing lithium target for generating a neutron radiation field and a preparation method and a self-repairing method thereof, the lithium target comprises a target material shell and lithium poured into the target material shell, the target material shell is not completely filled with the lithium poured into the target material shell, and a reserved gap is formed between the lithium poured into the target material shell and the target material shell. The target material bombarded by the proton beam is heated until lithium in the target material shell is in a molten state, bubbles generated by bombardment of the proton beam can be separated out of the lithium to the reserved gap, and lithium target self-repairing can be completed after the lithium in the target material shell is cooled and solidified. The self-repairing lithium target is simple in structure and easy to prepare, air holes left in the lithium target after proton beam bombardment can be easily removed only by heating the target material, self-repairing of the lithium target is achieved, frequent replacement of the target material is avoided, the service life of the lithium target is prolonged, and the working efficiency of an accelerator neutron source system is improved.