43 results about "Neutron activation" 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 provides a neutron dose evaluation method and system based on mobile phone neutron activation product analysis, and the method comprises the steps: constructing an equivalent medium model for replacing a real mobile phone, and carrying out the neutron energy spectrum solving through the mobile phone activation product. The neutron energy spectrum can be reconstructed on site in daily scenes without professional equipment, such as villages, streets and shopping malls, so that the uncertainty of individual dose is reduced to a level equivalent to that of a laboratory spectrometer, the dependence on a multi-ball spectrometer, a TOF spectrometer and professionals is thoroughly eliminated, rapid and accurate measurement of the neutron energy spectrum and large-scale population dose evaluation are realized, and the accuracy of the neutron energy spectrum is improved. And a basis is provided for delimiting the influence range of the nuclear event, judging the event level of the nuclear event and formulating a hierarchical medical rescue scheme.

The invention provides a cement-based material for immobilizing a neutron activation material, and belongs to the technical field of immobilizing materials for treating radioactive nuclear waste, the cement-based material comprises 5-10 parts of boron nitride, 80-120 parts of a gel material, 50-80 parts of a boric acid solution, 8-20 parts of an additive, 0.2-3 parts of a nucleating agent, 0.5-2 parts of a water reducing agent and 0.5-3 parts of a foaming agent, the concentration of the boric acid solution is 3-6 mol / L, the additive comprises sodium hydroxide and sodium aluminate, and the foaming agent comprises sodium hydroxide and sodium aluminate. The nucleating agent comprises one or more of synthetic hydrated calcium silicate gel, layered double hydroxides and a carbon nanomaterial. The admixture and boric acid are jointly added into the gel material, sodium hydroxide in the admixture can adjust the occurrence state of borate, sodium aluminate can promote formation of hydration products such as ettringite, and therefore the content of boron and hydrogen in a cement solidified body is effectively increased, and the shielding capacity of the cement solidified body for neutron rays is improved.

The application provides a pulse neutron element scanning and analyzing system for extraterrestrial exploration, which comprises a shell, a support, a neutron generator, a shielding body and a gamma spectrometer, the support is installed in the shell, the neutron generator, the shielding body and the gamma spectrometer are all installed on the support, and the shielding body is located between the neutron generator and the gamma spectrometer. The neutron generator, the shielding body and the gamma spectrometer are integrally installed on the support, the controllable neutron source is combined with the gamma spectrometer, the stratum is activated by the controllable pulse neutron generator, the element components are detected by gamma analysis, or the gamma generated by the natural radioactive nuclides and the cosmic background radiation is directly detected, element component analysis is carried out, the element measurement precision is improved, the detection time is shortened, more kinds of elements can be measured, and the application provides strong support for the measurement of more kinds of elements, and is suitable for lunar geology and resource exploration.

The present invention discloses a preparation system for non-radioactive tracer ceramsite with stable signal-to-noise ratio, comprising: a tracer ceramsite green body preparation device, a detection unit, a control system, a database, and an adjustment and optimization module; a method for real-time online regulating the content of tracer elements contained in the tracer ceramsite based on the ζ o value is established, eliminating the phenomenon of low or high content of tracer elements caused by uneven mixing or other factors during the production process of the tracer ceramsite, and accurately controlling the content of tracer elements within the set threshold. According to the feedback of the measured data ζ 测 downhole, the set threshold ζ 阈 of the tracer ceramsite is adjusted in real time. With the linkage between the wellhead and the downhole, stable signal-to-noise ratio can be achieved when monitoring the fracture information by the neutron activation prompt gamma ray method of the in-use tracer ceramsite in a complex fracturing environment, and the sudden increase and decrease of the captured gamma signal during fracture logging such as different logging tool parameters, wellbore environment, and oil and gas reservoirs can be avoided, thereby improving the logging success rate.

The invention discloses a neutron activation detection station system for rapidly detecting the element content of a material. The system can be used for rapidly detecting the element content of solid bulk materials in industrial production processes of building materials, coal, metallurgy, mines and the like. The system is composed of an element analyzer, a mechanical arm, a weighing scale, a coding sample barrel, a coding card reader, an electric roller conveyor and a PLC control system. The measurement time of a single sample is 30-300 seconds, the weight of the single sample is 1-10 kg, and a plurality of samples can be continuously and automatically measured. The method expands the application process points of the neutron activation technology, breaks through the traditional material detection mode, and has the advantages of wide application range, convenience in operation, high measurement precision, effective improvement of the detection efficiency and the like.

The invention discloses a solid-phase sylvite online analysis device based on a neutron activation method. The solid-phase sylvite online analysis device comprises a shell, a cover plate is arranged above the shell, a feeding structure is arranged above the cover plate, and a rotary scanning platform is fixedly connected to the bottom of the inner wall of the shell. By rotating the scanning platform, the sample can be automatically rotated and accurately positioned and adjusted in the neutron beam irradiation process, so that the neutron beam can be uniformly irradiated to the surface of the sample from multiple angles and directions, and the intensity and uniformity of each irradiation area are strictly controlled; and the phenomenon of over-strong or over-weak irradiation of a local area is avoided, so that the neutron excitation process of the whole sample is consistent and uniform. According to the method, the analysis accuracy is improved, errors possibly caused by uneven irradiation are eliminated, and the measurement result is more reliable.

The invention provides a method and a system for synchronously testing residual stress and hydrogen content. The method comprises the following steps: determining components and crystal structure types of a to-be-tested material; detecting the texture of the to-be-detected material; determining test crystal faces in three directions of the residual stress of the neutron diffraction detection sample, and testing lattice strain in the three directions; carrying out a prompt gamma experiment by using the standard sample to obtain a standard sample activation energy spectrum of neutron-activated prompt gamma; determining a series of to-be-tested positions for synchronously testing the residual stress and the hydrogen content, and further determining a sample table movement parameter corresponding to each measurement position; acquiring neutron diffraction data, testing lattice strain in three directions, and acquiring a signal of instant gamma at the same time; and constructing position corresponding information of neutron diffraction test and neutron activation instant gamma test data, and performing data processing to obtain final residual stress distribution and hydrogen content distribution. According to the detection method, the internal residual stress and the hydrogen content of the material can be simultaneously tested by utilizing a primary neutron diffraction experiment.

The application provides a direct-current high-voltage pulse strong-current pulse neutron generator, and relates to the technical field of neutron generators, comprising a main arc power module (3), a high-voltage accelerating power module (9) and a neutron tube (12). The neutron generator of the application is a strong-current pulse neutron generator working and driven in a direct-current high-voltage accelerating and pulse mode, can realize adjustable pulse parameters, is simpler to realize, widens the neutron pulse width from sub-microsecond to several milliseconds, and is helpful to widen the application field of the strong-current pulse neutron generator. For example, the ms-level strong-current pulse neutron source can be applied to the mass flow rate and component measurement based on neutron activation.

The utility model relates to the technical field of radiation detection, in particular to a shielding structure and a neutron activation analyser, the shielding structure comprises an outer shell and a partition plate, a hollow cavity is formed in the outer shell, the partition plate is arranged in the hollow cavity to divide the hollow cavity into two shielding cavities arranged along the length direction of the outer shell, and the shielding cavities are arranged in the outer shell. Each shielding cavity is filled with the shielding filler, the hollow cavity is divided into the two independent small shielding cavities through the partition plate, and by means of the arrangement, when the shielding structure is subjected to external physical interference, offset of the shielding filler is limited in each independent shielding cavity through the physical blocking effect of the partition plate; and the filler void ratio of the shielding filler of each shielding cavity only slightly fluctuates without obvious difference, so that the shielding effectiveness of the shielding structure is improved.

This invention discloses a gas purification device for neutron-activated argon isotope dating based on a D-D accelerator, belonging to the field of rare gas isotope mass spectrometry analysis and geological dating technology. Addressing the limitations of traditional gas purification systems, which suffer from large internal volumes and high static release rates, making them unsuitable for the efficient purification and enrichment of trace argon isotopes generated by the D-D accelerator neutron activation method, this invention employs an integrated 316L stainless steel substrate, internally integrating a main gas flow channel and multiple branch channels. The substrate houses a sample gas injection module, a primary purification module, a secondary purification module, a tertiary purification module, a vacuum preparation and monitoring module, a standard gas injection module, and a gas enrichment module. Each module is connected to the main gas flow channel via branch channels, achieving multi-stage purification of the mixed gas and low-temperature enrichment of trace argon isotopes. This device is used for gas purification in D-D accelerator neutron-activated argon isotope dating, meeting the requirements for efficient purification and enrichment of extremely small amounts of argon gas.

The present invention discloses an encrypted ray detection system based on a new mean hash identification algorithm, comprising a neutron activation encryption analysis component and an encrypted mean hash identification algorithm module. The neutron activation encryption analysis component comprises a neutron source, a non-uniform mask, and a detector. The non-uniform mask is disposed to the right of the neutron source, and the detector is disposed to the right of the non-uniform mask. Compared with traditional ray detection methods, the technology proposed in the present invention achieves dual encryption of sensitive information in both the physical and electronic fields. While protecting the sensitive information of the tested items, it also achieves high-precision identification. This technology has great application prospects in nuclear disarmament verification, border nuclear material security inspections, and various scenarios where sensitive information needs to be encrypted for detection. This invention effectively overcomes the difficulties in encrypted ray detection for certain special projects and greatly improves the application capabilities of ray detection technology.

The invention relates to a calibration method for characterising the elementary composition of a sample by neutron activation, the method comprising the following steps: receiving (201, 202), for different samples each consisting of one type of pure chemical element, an N-dimensional energy diagram, N being an integer strictly greater than 2, containing the number of occurrences of the detection, by a neutron activation device, of N coincident gamma rays, as a function of the energies of the N gamma rays, the energy diagram being determined by measurement or by simulation; for each sample, selecting (203) at least one set of points of interest in the energy diagram, on the basis of the knowledge of an energy level diagram of the pure chemical element; for each sample, concatenating (204), in order to obtain a characteristic vector of the chemical element, the projections, on one axis of the energy diagram, of each set of points of interest identified for all the samples; and defining (205) a calibration base by the set of characteristic vectors associated with each chemical element.

The present application relates to the technical field of nuclear power plant radiation protection, and discloses a kind of space dose rate radiation protection method based on irradiation supervision sample item calculation, comprising: step 1: the source item analysis is carried out to the supervision sample and scrap taken out, obtain the different nuclide species, quantity produced in unit volume of target material due to neutron activation at irradiation stop moment, step 2: the activity of different radioisotopes produced in unit volume and unit mass of target material due to activation at different irradiation time stop irradiation is calculated, step 3: a Monte Carlo calculation model is established, and the space dose rate caused by unit mass of supervision sample under different scenarios is carried out, step 4: the dose rate distribution of supervision sample is calculated, step 5: according to the dose rate distribution of supervision sample calculated in step 4, the kind and thickness of radiation protection material in different scenarios and positions are arranged, combined with the dose rate requirement of place, and reasonable radiation protection measures are formulated, and the present application can assist in reducing the dose of personnel during the overhaul of power station.

The utility model discloses a neutron activation detection station device for rapidly detecting the element content of a material. The device can be used for rapidly detecting the element content of solid bulk materials in industrial production processes of building materials, coal, metallurgy, mines and the like. The system is composed of an element analyzer, a mechanical arm, a weighing scale, a coding sample barrel, a coding card reader, an electric roller conveyor and a PLC control system. The measurement time of a single sample is 30-300 seconds, the weight of the single sample is 1-10 kg, and a plurality of samples can be continuously and automatically measured. The neutron activation detection device expands the application process points of the neutron activation technology, breaks through the traditional material detection mode, and has the advantages of wide application range, convenience in operation, high measurement precision, effective improvement of the detection efficiency and the like.

A neutron activator includes a neutron source and a first reflector-moderator. The neutron source has a housing extending along a longitudinal axis (B). A metallic target as part of the neutron source is provided to produce neutrons through the interaction with a proton beam, the target having at least one plate arranged transversally with respect to the longitudinal axis (B). The neutron source also includes a cooling circuit to cool the metallic target. The first reflector-moderator has an activation area configured to accommodate the neutron source and the material to be activated.

The invention provides a novel trigger imaging method, which is characterized in that two silicon photomultiplier modules are respectively coupled with two different scintillator detectors, so that stray radiation operation in a treatment chamber is sensed, and a detected radiation signal is converted into an optical signal. The SiPM detects scintillation photons and outputs corresponding current signals, the current signals are converted into voltage pulses through the current-voltage amplifier and then serve as input signals of the logic AND gate, and the logic AND gate is used for executing coincidence judgment so as to eliminate false trigger signals caused by neutron activation products generated by high-energy pulses (larger than or equal to 10 MV). And after logic summation, a shutter of the time-gated CCD camera is triggered to carry out imaging, and an imaging signal is processed by the data processing device and then is fed back to the linear accelerator in real time. The system has the characteristics of remote triggering, high response precision and no limitation of a linear accelerator, and the imaging flexibility and the synchronization precision in the radiotherapy process are remarkably improved.

A kind of miniature neutron detector conical surface light-concentrating heat-resistant probe, its characteristics include luminous body, light-concentrating cylinder, light-concentrating lens, armored shell, fixing sleeve, compression spring, set screw and optical fiber;Flasher material is made into cylindrical luminous body by using capillary glass tube, the volume of flasher material increases, the neutron activation reaction of flasher material is more sensitive, the light-emitting surface area increases, effectively improve the number of photons generated by flasher material, then light emitted by luminous body is collected, refracted and converged by light-concentrating cylinder and light-concentrating lens, compared with traditional detector probe, effectively reduce the light attenuation of light signal in the process of optical fiber transmission due to random angle incidence, different energy level photon distribution is more uniform and concentrated, the signal strength after conversion is strong, signal pulse accumulation is less, it is easier to be read, greatly improve the detection efficiency of detector, have good enlightenment effect on the technical problems faced by the field, have good popularization and application value.

The present disclosure relates to a microsphere having a plurality of pores with a gradient characteristic gradually decreasing along the direction from the surface to the center of the microsphere, wherein the microsphere includes: a first nuclide, which is distributed in the microsphere and whose concentration in the center of the microsphere is greater than that in the surface of the microsphere; and a second nuclide and gradually decreasing along the direction from the surface to the center of the microsphere, wherein the first and second nuclides are capable of being radioactive after neutron activation to produce β-rays, γ-rays or a combination thereof. The present disclosure also provides methods of preparing a microsphere. Radiotherapy, imaging and tracking functions can be achieved by introducing the first and second nuclides into the microsphere, and the plurality of pores increases the surface area of the microsphere to enhance adhesion with a shell.

The invention discloses a neutron activation detection station for rapidly detecting the element content of a material. The equipment can be used for rapidly detecting the element content of solid bulk materials in industrial production processes of building materials, coal, metallurgy, mines and the like. The equipment consists of an element analyzer, a mechanical arm, a weighing scale, a coding sample barrel, a coding card reader, an electric roller conveyor and a PLC (Programmable Logic Controller) control system. The measurement time of a single sample is 30-300 seconds, the weight of the single sample is 1-10 kg, and a plurality of samples can be continuously and automatically measured. The method expands the application process points of the neutron activation technology, breaks through the traditional material detection mode, and has the advantages of wide application range, convenience in operation, high measurement precision, effective improvement of the detection efficiency and the like.

The invention relates to the technical field of nuclear power plant radiation protection, and discloses a space dose rate radiation protection method based on irradiation supervision sample source item calculation, which comprises the following steps: step 1, carrying out source item analysis on a taken supervision sample and debris to obtain different nuclide types and quantities generated by neutron activation in a target material per unit volume at the irradiation stop moment, the method comprises the steps of 1, establishing a Monte Carlo calculation model, 2, calculating the activity of different radionuclides generated by activation in target materials of unit volume and unit mass when irradiation is stopped at different irradiation time, 3, establishing the Monte Carlo calculation model, and developing the space dose rate caused by unit mass supervision samples in different scenes, 4, calculating the dose rate distribution of the supervision samples, and 5, calculating the activity of different radionuclides generated by activation in the target materials of unit volume and unit mass when irradiation is stopped at different irradiation time. And 5, according to the dose rate distribution of the supervision sample calculated in the step 4, arranging the types and thicknesses of radiation protection materials in different scenes and positions, and formulating reasonable radiation protection measures in combination with site dose rate requirements.

A neutron activator for neutron activation of a material, the neutron activator being configured to produce neutrons from an interaction with a proton beam (7), the neutron activator comprising:a neutron source comprising a metallic target (1), anda Beryllium first reflector-moderator (4) peripheral to the neutron source and comprising a neutron activation area (10) configured to accommodate the neutron source and the material to be activated, the neutron activation area (10) of the first reflector-moderator (4) comprising a bore configured to accommodate the neutron source.

A neutron activation detector comprises a first enclosure, a plurality of electrical leads, and an activation medium disposed within the enclosure. The activation medium consists substantially of a material that is activated by fast neutrons, and is arranged within the enclosure so that activation of the material by fast neutrons results in a current between the plurality of electrical leads.

The invention discloses a nuclear fuel element detection device and method based on gamma ray imaging and neutron activation, and relates to the technical field of nuclear fuel element detection, the detection device comprises a mechanical structure, a shielding structure, a transmission structure and a measurement control structure; the mechanical structure comprises a support assembly. The shielding structure comprises a first lead chamber, a second lead chamber and a third lead chamber which are installed on the support assembly at intervals. The transmission structure comprises a span bridge installed on the support assembly, an objective table is installed on the span bridge, and the objective table moves on the span bridge through power provided by a traction structure. The span bridge is provided with a limiting sensor used for providing position information of the objective table. The measurement control structure comprises a PLC control system. According to the device and the method, the neutron activation technology and the gamma ray imaging technology are integrated, and the 235U uniformity and the enrichment degree of the fuel element can be accurately and rapidly detected.

The utility model discloses an ore pulp pretreatment device suitable for a neutron activation ore pulp element on-line analysis technology, which is an ancillary facility of a neutron activation ore pulp element on-line analyzer and mainly comprises a pneumatic valve, a blending barrel, a stirrer, a circulating pump, a concentration meter and the like, the device described by the utility model is combined with a neutron activation ore pulp element on-line analyzer to realize automatic switching detection of ore pulp in two flow channels; the device can be used for adjusting the concentration of the ore pulp, the ore pulp with large concentration difference is adjusted to the same concentration, and the detection error of the neutron activated ore pulp on-line element analyzer caused by the difference of the concentration of the ore pulp is eliminated.

A first aspect of the invention relates to a system for the in-line preparation of a vitrifiable mixture having a target composition, the system comprising: - a unit for dispensing raw materials, which is able to provide a premix comprising cullet, preferably at least 20% by weight of cullet; - a conveyor which is able to move the premix; - a unit for the in-line measurement of the composition of the premix by neutron activation, the in-line measurement unit comprising: • at least one neutron emission source configured to irradiate all or part of said premix; • at least one gamma ray detector configured to detect the gamma rays emitted by the premix when it is irradiated by the neutron emission source; and • a digital processing device configured to calculate, from the signal of the gamma ray detector, the content of chemical elements present in the premix, and optionally configured to estimate the water content and / or the content of organic compounds in the premix; and - at least one means for adjusting the premix to obtain the vitrifiable mixture having the target composition. The invention also relates to a method for the in-line preparation of a vitrifiable mixture having a target composition.

According to a first aspect, the invention relates to an online preparation system for a vitrifiable mixture of target composition, the system comprising: - a raw material distribution unit capable of supplying a premix comprising cullet, preferably at least 20% by mass of cullet; - a conveyor capable of moving the premix; - an online measurement unit for the composition of the premix by neutron activation, the online measurement unit comprising: • at least one neutron emission source configured to irradiate all or part of said premix; • at least one gamma ray detector configured to detect the gamma rays emitted by the premix when it is irradiated by the neutron emission source;and • a digital processing device configured to calculate, from the gamma ray detector signal, the chemical element content present in the premix, and optionally configured to estimate the water content and / or the organic compound content in the premix; and at least one means for adjusting the premix to obtain the vitrifiable mixture of target composition. The invention also relates to a method for preparing a vitrifiable mixture of target composition online. Figure 1.

The invention discloses a corrosion product source item deposition characteristic on-line monitoring device and method based on neutron source activation. The corrosion product source item deposition characteristic on-line monitoring device comprises a water storage tank, a corrosion sample activation test section, a simulation reactor core test section, a main pipeline heat pipe section simulation body, a steam generator simulation body and a main pipeline cold pipe section simulation body. A neutron source is arranged in the corrosion sample activation test section and is used for performing irradiation activation on a corrosion product in a test solution; and gamma-ray energy disperse spectrums D1, D2, D3 and D4 are respectively arranged beside the simulation reactor core test section, the main pipeline heat pipe section simulation body, the steam generator simulation body and the main pipeline cold pipe section simulation body. According to the method, deposition behaviors of corrosion products in a pressurized water reactor primary loop coolant after being activated by neutrons on the surfaces of a fuel element, a steam generator heat transfer pipe and a main pipeline are simulated in a laboratory environment, and deposition radioactive characteristics of the corrosion products on the surfaces of all parts after a neutron source is activated are detected on line through a gamma energy disperse spectroscopy; and online measurement of source item deposition characteristics of surface corrosion products of different parts is realized.

To provide a microsphere and a preparing method thereof.SOLUTION: The present invention relates to a microsphere which has a plurality of pores, which have a gradient feature of gradually decreasing along a direction from a surface to a center of the microsphere, wherein the microsphere includes: first nuclide which is distributed in the microsphere and whose concentration is greater in the center than in the surface of the microsphere, and second nuclide gradually decreasing from the surface toward the center of the microsphere, wherein the first nuclide and the second nuclide are capable of being radioactive through neutron activation to produce β rays, γ rays or a combination thereof. The present disclosure also provides a method of preparing the microsphere. The microsphere can have functions of radiotherapy, imaging and tracking by introducing the first nuclide and second nuclide into the microsphere, and can increase in adhesion to a shell layer by increasing a surface area through the plurality of pores.SELECTED DRAWING: Figure 1C

Calibration method for characterizing the elemental composition of a sample by neutron activation, the method comprising the following steps: Receiving (201, 202), for different samples each composed of one type of pure chemical element, an N-dimensional energy diagram, N being an integer strictly greater than 2, containing the number of occurrences of the detection, by a neutron activation device, of N coincident gamma rays, as a function of the energies of the N gamma rays, the energy diagram being determined by measurement or by simulation; For each sample, selecting (203) at least one set of points of interest in the energy diagram, from knowledge of an energy level diagram of the pure chemical element; For each sample, concatenating (204), to obtain a characteristic vector of the chemical element, the projections, on an axis of the energy diagram,For each set of points of interest identified for all samples, define (205) a calibration basis by the set of characteristic vectors associated with each chemical element. Figure 2,