79 results about "Neutron count" patented technology

Systems and methods for measuring soil moisture are provided. The system may include a neutron sensor configured to be disposed at a sampling location and including one or more neutron detectors configured to detect fast neutrons and thermal neutrons at the sampling location, and a computing device including at least one data processor and a memory storing instructions, the instructions are configured to cause the processor to perform operations including receiving a first electrical signal characterizing a fast neutron count at a sampling location and a second electrical signal characterizing a thermal neutron count at the sampling location from the neutron sensor, determining a ratio of fast neutrons to thermal neutrons present at the sampling location, a soil moisture measurement is determined based on the ratio, and the soil moisture measurement is provided.

The invention relates to a neutron spectrum measurement method and system, and the method comprises the steps: obtaining a neutron signal obtained through the detection of an incident neutron beam through a plurality of detectors; after the neutron signal is processed, a processed signal is obtained; obtaining the neutron counting rate of each detector based on the processing signal; the initial neutron counting rate of the jth energy interval in the incident neutron beam is set as # imgabs0 #, the initial neutron counting rate is substituted into a formula for iterative calculation, and when the absolute value of the difference value of # imgabs1 # and # imgabs2 # is smaller than a preset first threshold value, # imgabs3 # is the neutron counting rate of the jth energy interval in the incident neutron beam; and calculating the neutron counting rates corresponding to the n energy intervals in the incident neutron beam corresponding to each detector in sequence to obtain the neutron energy spectrum of the incident neutron beam. The measuring method is simple in measuring process and high in accuracy.

The invention relates to a neutron measuring device (1). The device (1) comprises a housing (90), a high-density polyethylene block (10) in the housing (90), a shell made of neutron-absorbing material (20) integrated into the block (10), a first scintillation neutron detector (30) located inside the shell (20) and capable of emitting a signal proportional to the number of neutrons detected per unit of time, and a module (40) capable of converting the signal into a neutron count rate.

Provided in the present disclosure is a neutron poison monitoring apparatus. The neutron poison monitoring apparatus comprises: a container, which is used for accommodating a liquid to be tested that contains a neutron poison; a neutron source, which is configured to emit neutrons to said liquid; a detector, which is configured to detect the number of neutrons and / or the number of photons in said liquid; a multi-channel scaler, which is configured to send to a neutron poison monitoring control apparatus the number of neutrons and / or the number of photons detected by the detector; the neutron poison monitoring control apparatus, which is configured to control the neutron source to emit the neutrons to said liquid, control the detector to detect the number of neutrons or the number of photons in said liquid within a time range after the neutron source is controlled to stop emitting neutrons to said liquid, so as to obtain a plurality of detection values, use a background value to correct each detection value among the plurality of detection values, so as to obtain a plurality of corrected values, and use the plurality of corrected values to determine the concentration of the neutron poison in said liquid; and a shielding device, which is configured to shield external interference received by said liquid and the detector.

The invention provides a runner chamber wall thickness and void synchronous detection method, and relates to the technical field of hydro-power engineering nondestructive testing, S1, modular calibration: preparing a combined simulation block of a metal standard plate and an organic material plate, establishing a concrete water content inversion model and a void depth model segmented according to the thickness of a steel lining, and outputting calibration parameters; s2, field data acquisition: arranging measuring lines along a vertical welding seam and a longitudinal rib plate of the runner chamber, acquiring ultrasonic echo time and a thermal neutron counting rate, correcting the wall thickness in combination with the temperature of a steel lining, performing secondary verification on an abnormal measuring point, and outputting an original data set S = {}; and S3, machine learning signal processing: performing wavelet packet decomposition to extract energy ratio characteristics, and calculating thermal neutron counting rate fluctuation characteristics. Precise collaborative detection of the wall thickness and the void is realized through a link-by-link process of modular calibration, field data acquisition, machine learning signal processing, segmented collaborative modeling and Internet of Things data management.

The invention belongs to the technical field of nuclear material measurement and analysis, and particularly relates to a neutron detection method for measuring the mass of a nuclear material and a radiation dose field of the nuclear material. According to the embodiment of the invention, the method comprises the steps: carrying out the energy response calculation and calibration of a detector through a parallel beam standard neutron source, and obtaining a calibration factor; performing energy response calculation and calibration on the detector by taking a to-be-measured object as a target object, determining the energy response and fluence-ambient dose equivalent conversion coefficient of the detector in a radiation field of the to-be-measured object, and realizing simultaneous measurement of a neutron counting rate, a fluence rate and an ambient dose equivalent rate; and the requirements of carrying out radiation dose field monitoring while carrying out quantitative analysis on the to-be-detected object in a special scene are met. The technical scheme of the invention can be popularized and applied to fixed-point monitoring of a to-be-detected system with known or measurable nuclear material source item composition and isotope abundance in nuclear facilities, or retention volume analysis and radiation dose measurement before transfer or treatment of some equipment for treating nuclear materials.

This invention relates to a welding temperature gradient control method and apparatus based on neutron source residual stress detection, belonging to the field of welding control technology. This technology establishes a correlation between laser power, beam size, scanning rate, metal type, and temperature by constructing a temperature field data acquisition module and a heating and cooling module for the welding process, and by using laser-assisted local heating and forced substrate cooling devices. It develops a temperature gradient control method to achieve online physical simulation of the temperature gradient between the welding zone and the substrate, solving the problem of mismatch between the welding cooling rate and the neutron data acquisition rate, and realizing in-situ online testing of the stress field near welding conditions.

A method for measuring reactor reactivity and subcriticality. The method for measuring reactor reactivity comprises the following steps: adjusting the neutron source intensity of the reactor to change the neutron count of the reactor; and obtaining the measured reactivity of the reactor according to the change value of the neutron count. In the method of this embodiment, the error between the measured value-measured reactivity and the actual reactivity obtained by measuring the actual reactivity of the reactor using the change value of the neutron count is small, and a more accurate actual reactivity can be obtained, which is beneficial to the critical safety supervision of the reactor.

The present invention discloses a method for detecting the grouting fullness of grouting sleeves, which includes: preparing a standard grouting fluid, performing neutron detection on each detection point of grouted and ungrouted sleeves one by one, and taking the detection results as a reference standard neutron number library; before grouting the sleeves in the component, performing neutron detection, and taking the measured neutron quantity as the background value; grouting the sleeves in the component with the prepared standard grouting fluid, performing neutron detection on each detection point one by one, and the measured neutron number is the neutron number with the background value; subtracting the neutron number with the background value from the background value to obtain the actually measured neutron number of the sleeves in the component; comparing and analyzing the actually measured neutron number of the sleeves in the component with the reference standard neutron number to finally obtain the detection result. According to the grouting situation, the final detection result can be divided into three levels: ungrouted, insufficient grouting, and full grouting; insufficient grouting is further divided into air-filled pores and water-filled pores. The present invention makes full use of the characteristic that neutrons can penetrate metal, and realizes the detection of the grouting fullness of grouting sleeves.

The invention discloses a borehole influence factor aperture correction method for uranium fission instant neutron logging, and aims to solve the problem of neutron counting rate response deviation caused by borehole size change in a uranium mine logging process. Time spectrums of thermal neutrons and epithermal neutrons in different apertures in uranium fission instant neutron logging are obtained, and the rule that the time spectrums of the thermal neutrons and the epithermal neutrons change along with the hole diameter is researched. And based on a numerical simulation result, a fitting formula and a correction coefficient of the aperture influence factors are solved. The correction method can be used for analyzing the influence of the aperture size change on the counting rate of the neutron detector, effectively improves the uranium mine grade evaluation accuracy under the complex borehole condition, and is especially suitable for well logging interpretation of non-standard borehole diameters and diameter-expanded stratums.

The embodiment of the application provides a kind of neutron flux abnormality detection method and device, electronic equipment and storage medium, belong to nuclear power plant safety technical field.The method comprises: screening reference nuclear power reaction unit.Get the first reference counting rate detection module in multiple continuous preset time steps under the core neutron counting rate.Acquire concentration influence factor, original neutron source source intensity and reference neutron source source intensity.According to the first detection sensitivity, the first reference sensitivity, the core neutron counting rate, the concentration influence factor, the original neutron source source intensity and the reference neutron source source intensity, the predicted neutron flux of the core basket is obtained by calculation.The first loading of pressurized water reactor nuclear power reaction unit is carried out, and the target neutron counting rate is obtained.According to the target neutron counting rate and the first detection sensitivity, the target neutron flux is obtained by calculation, and the abnormality is detected based on the target neutron flux and the predicted neutron flux.The embodiment of the application can improve the efficiency of neutron flux abnormality detection.

A device for evaluating uranium content and hydrogen porosity while drilling includes a probe having a pulsed neutron generator for emitting a pulse of neutrons, a single neutron detector, a neutron counting unit for measuring over time a number of neutrons backscattered from hydrogen nuclei and a number of prompt fission neutrons resulting from interactions with uranium nuclei. The device also includes a hydrogen porosity evaluation unit for evaluating the hydrogen porosity using a total number of backscattered neutrons and a uranium evaluation unit for evaluating the uranium content using a total number of prompt fission neutrons.

The present invention discloses a method for inverting snow water equivalent and soil water content based on neutron flux, which relates to the field of meteorological science and technology, and includes: conducting a calibration experiment at an experimental site, measuring the thermal neutron count rate, epithermal neutron count rate, soil water content and snow water equivalent, substituting the experimental results into a database, and calibrating parameter N e0 and N t0 ; setting an epithermal neutron detector at the experimental site, and then selecting any one of the thermal neutron detector, soil water content sensor, and snow water equivalent sensor to conduct detection at the experimental site; taking the detection result as the original data, and finding the sample point data closest to the original data in the database, which is the inversion result of the snow water equivalent and soil water content. The method of the present invention corrects the influence of snow water equivalent in the actual measurement of soil water content by the cosmic ray neutron method, or corrects the influence of soil water content in the measurement of snow water equivalent, and can also determine the snow water equivalent and soil water content simultaneously by measuring the ground epithermal neutron and thermal neutron count rates.

The application discloses a formation porosity measurement method, system, logging instrument and medium, and relates to the field of oil and natural gas development. First, the hot neutron counts detected by a first hot neutron detector and a second hot neutron detector in a D-D neutron porosity logging instrument are acquired respectively. Then, gamma time spectrum information detected by a gamma detector in the D-D neutron porosity logging instrument is acquired, and a wellbore Sigma value is determined according to the gamma time spectrum information. Finally, the formation porosity is determined by combining the first hot neutron count, the second hot neutron count and the wellbore Sigma value. The scheme does not need to measure the wellbore size and the fluid type, and improves the accuracy of formation porosity calculation.

The invention relates to a neutron spectrum and proton spectrum distinguishing measurement method and device based on a multi-ball measurement system, and the method comprises the steps: obtaining a current neutron and proton spectrum through employing an SAND-II few-channel spectrum unfolding algorithm based on a neutron and proton response function matrix of the multi-ball measurement system and an original count obtained through a to-be-measured field test; obtaining an original deviation between the measured value and the calculated value; reducing the count of each channel of the current neutron spectrum according to a set proportion, and calculating based on the SAND-II few-channel spectrum unfolding algorithm again to obtain a new proton spectrum, a new proton count, a new neutron spectrum and a new neutron count, and obtaining a new deviation between the total count and the original count; obtaining a plurality of deviations by changing the set proportion for multiple times; and finally, taking the neutron spectrum and the proton spectrum corresponding to the minimum value in all the deviations as measurement results. According to the invention, the neutron and proton real-time distinguishing measurement with relatively wide energy range and relatively high precision in a high-altitude region of the earth or in other neutron-proton mixed fields is realized.

The present invention relates to a method and system for detecting hollowing of heterogeneous space under steel plates based on a joint detection model. The method comprises the following steps: arranging a survey line on a steel-lined concrete structure, dividing the survey points at equal intervals along the survey line to form a grid, using an echo method to perform full-domain detection on each survey line, and collecting full-domain echo signals; obtaining a spectrum curve using fast Fourier transform according to the echo signal result, and screening the potential concrete hollowing defect area and hollowing area under the detection surface according to the spectrum curve; detecting the concrete hollowing defect area using a neutron scattering method, and collecting the thermal neutron count rate of each survey point on the survey line where the hollowing defect area is located; calculating the equivalent hollowing height value of each survey point according to the thermal neutron count rate result; and calculating the average hollowing height value by combining the hollowing area measured by the echo method and the equivalent hollowing height value measured by the neutron scattering method. The present invention can solve the problem that the accuracy and efficiency of hollowing detection of multi-layer heterogeneous space under steel plates in engineering cannot be taken into account at the same time.

The invention relates to a directional neutron energy spectrum measuring device which is characterized in that a moderation box body is internally provided with moderation liquid and is provided with an upward opening end, a neutron beam is emitted perpendicular to any box body side wall of the moderation box body, and the moderation box body is used for moderating the neutron beam; the thermal neutron detection system is placed in the moderation box body and is used for detecting neutron counts corresponding to the neutron beams at a plurality of positions in the moderation box body to obtain a neutron energy spectrum; and the moving assembly is connected with the thermal neutron detection system, is mounted at the opening end of the moderation box body, and is used for driving the thermal neutron detection system to move in the moderation box body in multiple directions. The purpose of driving the thermal neutron detection system to move in the moderation liquid of the moderation box body through the moving assembly is achieved, and therefore the technical effects that one thermal neutron detection system can move in the moderation liquid, a moderation ball does not need to be replaced, operation is easy, and the risk that employees are irradiated is reduced are achieved.

Disclosed are an apparatus and a method for measuring a neutron beam of ex-vessel of a small modular reactor (SMR). The apparatus for measuring a neutron beam of ex-vessel of a small modular reactor of the present invention comprises: a detector for detecting a current generated by ionization of a neutron beam leaking from a reactor vessel; a preamplifier for receiving a current value of the detector to amplify the current value; a signal processing module for calculating the number and intensity of neutrons leaking in the reactor vessel on the basis of the current value amplified by the preamplifier; and a water level measurement device for transmitting a measurement value obtained by measuring the water level of a medium accommodated in the space between the reactor vessel and a containment vessel to the preamplifier, wherein the preamplifier holds gain value data determined in accordance with the water level of the medium and applies and compensates a gain value in accordance with the measurement value transmitted from the water level measurement device.

The present disclosure provides a neutron poisoning monitoring device. The neutron poisoning monitoring device comprises: a container for containing a liquid to be tested including neutron poisoning; a neutron source configured to emit neutrons to the liquid to be tested; a detector configured to detect the number of neutrons and / or photons in the liquid to be tested; a multi-channel calibrator configured to send the number of neutrons and / or photons detected by the detector to a neutron poisoning monitoring control device; the neutron poisoning monitoring control device is configured to control the neutron source to emit neutrons to the liquid to be tested, and within a time range after the neutron source is controlled to stop emitting neutrons to the liquid to be tested, control the detector to detect the number of neutrons or photons in the liquid to be tested to obtain multiple detection values, use the background value to correct each of the multiple detection values ​​to obtain multiple correction values, and use the multiple correction values ​​to determine the neutron poisoning concentration in the liquid to be tested; a shielding device configured to shield the liquid to be tested and the detector from external interference.

A method for measuring reactor reactivity and subcriticality. The reactor reactivity measurement method comprises the following steps: adjusting the actual reactivity of the reactor to change the neutron count of the reactor; and obtaining the measured reactivity of the adjusted reactor according to the change value of the neutron count. In the method of this embodiment, the error between the measured value-measured reactivity and the actual reactivity obtained by measuring the actual reactivity of the reactor using the change value of the neutron count is small, and a more accurate actual reactivity can be obtained, which is beneficial to the critical safety supervision of the reactor.

The present invention relates to a neutron gamma stacking waveform identification method, and specifically to a neutron gamma pulse waveform stacking identification method under high counting rate conditions. The method solves the technical problem that existing neutron gamma waveform identification methods do not consider the change of the neutron gamma waveform trailing edge, resulting in a low accuracy rate. The neutron gamma pulse waveform stacking identification method under high counting rate conditions includes the following steps: 1) collecting and storing neutron gamma single waveform mixed signals; 2) obtaining a neutron data set and a gamma data set S1; 3) constructing a test set P1 of neutron gamma stacking waveforms; 4) obtaining a neutron data set and a gamma data set S2; 5) constructing a feature parameter set T; 6) constructing a training set sample library P2; 7) constructing a training data set P3; 8) training a neural network, using the trained neural network to identify all waveforms in the test set P1 and output their predicted labels, thereby completing neutron gamma pulse waveform stacking identification under high counting rate conditions.

The invention discloses a two-parameter detector and a two-parameter real-time detection method and system for BNCT, and the detector comprises a sensing element which is made based on a Li2B4O7 crystal; the signal acquisition module is configured to respectively acquire an electric pulse signal and an electric parameter signal for indicating neutron counting from the sensing element; the signal conversion module is used for converting an electric pulse signal for indicating neutron counting into effective pulse counting and converting the electric parameter signal into a resistance parameter; the model calculation module is used for carrying a two-parameter response model and carrying out data processing on the resistance parameters based on the model to obtain corrected neutron flux; the technical problems that in the BNCT treatment process, a gamma-ray energy spectrum analysis method adopted in the prior art is likely to cause interference on the measurement result of the boron concentration, and real-time and rapid monitoring of the boron concentration is difficult to achieve are solved.

The invention provides a quality measurement method, a model training method, electronic equipment, a storage medium and a program product. The method comprises: obtaining neutron counting data of a nuclear material to be measured within a first measurement duration, the first measurement duration being less than a second measurement duration, and the second measurement duration being a duration for performing neutron multiplex measurement on the nuclear material to be measured based on a preset mathematical model; based on the neutron counting data, a neural network model is used for conducting mass measurement on the to-be-measured nuclear material, a measurement result output by the neural network model is obtained, and the measurement result represents the mass of the to-be-measured nuclear material. By means of the scheme, the accuracy of nuclear material quality measurement can be improved under the condition that the measurement time of the to-be-measured nuclear material is shortened.

A method for measuring an oil saturation value of a subterrain formation uses a tool having multiple dual-function detectors that detect neutrons and gamma rays. The method includes emitting neutrons into the formation, detecting neutrons and gamma ray signals form the formation using the detectors, determining formation parameters including the formation type and formation porosity, and further determining parameters such as C / O ratios at each of the detectors, a total neutron count rate at each of detectors, a fast neutron count rate at each of detectors, and a thermal neutron count rate at each of the three or more detector, and calculating the oil saturation value using the determined parameters.

The application discloses a porosity calculation method and system for complex reservoirs, which comprises the following steps: selecting a marker layer, and performing preliminary correction on original neutron and density logging curves of a target layer by using deviation analysis according to skeleton neutron values and skeleton density values of the marker layer; based on core analysis test data of the target layer, core data is homed in the preliminary corrected neutron and density logging curves, and a fusion analysis chart is formed based on this; the fusion analysis chart is corrected in neutron values by using a neutron multiplication factor initial value, and a neutron multiplication factor final value is determined by comparing a formation porosity calculation value obtained by using the corrected neutron and density with a formation porosity measurement value; and the original neutron and density logging curves are comprehensively corrected by using the preliminary correction amount and the neutron multiplication factor final value, so that the formation porosity of a single well is obtained.

The present application relates to the technical field of neutron logging, and particularly relates to a neutron logging method, system and electronic equipment for measuring formation porosity, the method comprising: when a target formation of a well to be measured is a high-porosity formation, substituting a thermal neutron count ratio of the target formation and formation density of the target formation into a high-formation porosity model to obtain formation porosity of the target formation; when the target formation of the well to be measured is a low-porosity formation, substituting the thermal neutron count ratio of the target formation and the formation density of the target formation into a low-formation porosity model to obtain formation porosity of the target formation. Compared with the prior art, the present application starts from neutron transport theory, fully considers the influence of non-elastic scattering of neutrons on neutron moderation, and finally improves the accuracy and sensitivity of porosity measurement of the target formation. Moreover, the instruments used in the method are common instruments and equipment in the field, which are convenient to operate, implement and test.

The invention provides a device and a method for measuring the surface density of a neutron absorbing material B10. The device comprises a control system, a driver, a neutron detector and a sample holder. The sample rack is used for slidably arranging a to-be-tested sample and a standard sample; the neutron detector is arranged on the sample rack and is used for measuring and outputting neutron data after a neutron beam passes through the to-be-measured sample or the standard sample; the control system is used for receiving measurement data of the neutron detector, calculating the B10 surface density of the to-be-measured sample and controlling the measurement position of the to-be-measured sample and / or the standard sample on the sample rack; the driver is respectively connected with the control system and the sample rack, and drives the to-be-tested sample and / or the standard sample to horizontally move and / or vertically move on the sample rack based on an instruction of the control system. According to the invention, the measurement position of the neutron absorption material can be accurately controlled, accurate measurement of the B10 surface density is realized by using the standard sample with the same raw material and processing technology as the to-be-measured sample, and the neutron absorption performance of the neutron absorption material is accurately evaluated.

The invention relates to the field of neutron energy spectrum detection methods, in particular to a rotating hemisphere neutron energy spectrum detection device and method based on a liquid moderator, and the device comprises a liquid pumping and injecting device, a center detector, a plurality of mutually independent moderation cavities, a rotating hemisphere concentric spherical shell and a rotating device. The method comprises the following steps: simulating characteristic peak response or neutron response under different thickness moderator combinations by utilizing a Monte Carlo method, and compiling the characteristic peak response or neutron response into a corresponding response function matrix; a center detector is used for measuring characteristic gamma ray counts or thermal neutron counts under different thickness moderator combinations to form a count value matrix; and solving by combining the response function matrix and the measured count value matrix to obtain the neutron energy spectrum of the to-be-measured region. According to the invention, the filled moderator combination is directly rotated, and the water pumping and injection time is saved compared with a water pumping and injection type single-sphere neutron energy spectrometer.

A method for measuring porosity of a subterranean formation includes the steps of: positioning a nuclear logging tool having one or more neutron sources and two or more dual function detectors in a subterranean formation; causing the one or more neutron sources to emit neutrons in a plurality of neutron pulses toward the subterranean formation and to generate neutrons and gamma rays in the subterranean formation; obtaining one or more neutron count rates for each of the two or more detectors; determining a formation type of the subterranean formation based on the gamma rays received by the one or more detectors; calculating one or more neutron count rate ratios between the neutron count rates of two detectors selected from the two or more detectors; and obtaining one or more formation porosities based on the formation type and the one or more neutron count rate ratios.

The invention relates to a fractured sandstone uranium mine prompt neutron logging numerical simulation method based on a disperse multi-angle random statistical theory. The method comprises the steps of firstly establishing a geological model of the fractured sandstone-containing uranium mine based on a dispersion multi-angle theory; then the simulation pulse neutron source emits neutrons to the stratum, the neutrons and uranium in the cracks are subjected to fission reaction, and instant neutrons are released; then simulating the movement and reaction process of neutrons in the stratum; and finally, recording logging response by a neutron flux counter, and obtaining epithermal neutron count and thermal neutron count according to the energy range. Through tests, the fractured sandstone uranium mine prompt neutron logging numerical simulation method based on the scattered multi-angle random statistical theory can effectively simulate prompt neutron logging responses of sandstone uranium mines under fractures of different angles, and epithermal neutron counting and thermal neutron counting are obtained.