93 results about "Nuclear detection" patented technology

A radiation detection system includes many receivers to continuously receive radiation emission data from at least some of a sufficient density of dispersed detectors capable of communicating geo-positions and photon emission counts over a network; the data includes gamma intensities, time stamps, and geo-positions. A processor builds digital image data of the received radiation data for a geographic area by treating gamma-ray proton data from each dispersed detector as a pixel in a low-light image. The processor continuously executes a plurality of statistical computational analyses on the digital image data to separate detected radiation signals from random, undesired signal noise, and known signal noise or sources. The statistical computational analyses include match-filter and / or other convolution techniques. An interface reports to a user when the computational analyses result in detection of a radiation signal and reports a location of one or more of the dispersed detectors that contribute to the detection.

Being in use for shielding strong magnetic field (MF), the magnetic shielding device with multilaminar composite structure solves issue that the design of magnetic shielding photomultiplier is unable to shield strong MF. Using multilaminar composite structure, the magnetic shielding device includes three layers from outer to inner: silicon steel assembly as middle layer, alloy assembly as inner layer, and solenoidal inductor as outer layer. The solenoidal inductor generates MF opposite to outer MF so as to weaken strong MF greatly. With higher saturation of MF, the silicon steel assembly reduces outer MF to a few Gauss further. Possessing quite high magnetic permeability of weak MF, the alloy assembly in innermost layer reduces residual MF to lower than 0.001 Gauss being far lower than level of earth MF. The invention makes shielded photomultiplier operate normally under strong MF. The invention has wide application in technical areas of nuclear electronics and nuclear detection.

The invention discloses a Monte Carlo simulation method for moving body dose based on data field segmentation. The method includes the steps of: a) acquiring calculated input parameter, b) forming a body bounding box on the basis of a tree structure of an entity so as to acquire a body discrete state sequence, c) segmenting particle track data into a sensitive data field and a non-sensitive data field based on the body bounding box, d) alternately processing circulating simulations of the two data fields, processing a relative state transition of particles when entering or exiting the sensitive data field, delivering the particles in the same model, dividing each of the particles entering the sensitive data field split into two particles respectively of the weights of 1 / m and 1-1 / m, and then delivering the two particles respectively in two data fields, and e) acquiring the precise dose change of the human body in movements through a linear interpolation. The method can be used for accurately calculating dose changes of the moving body and every organ, and is high in speed and widely applicable to fields such as maintenance and assembling, roaming and nuclear detection under the circumstances of radiation shield and nuclear radiation.

A radiation detection system includes many receivers to continuously receive radiation emission data from at least some of a sufficient density of dispersed detectors capable of communicating geo-positions and photon emission counts over a network; the data includes gamma intensities, time stamps, and geo-positions. A processor builds digital image data of the received radiation data for a geographic area by treating gamma-ray proton data from each dispersed detector as a pixel in a low-light image. The processor continuously executes a plurality of statistical computational analyses on the digital image data to separate detected radiation signals from random, undesired signal noise, and known signal noise or sources. The statistical computational analyses include match-filter and / or other convolution techniques. An interface reports to a user when the computational analyses result in detection of a radiation signal and reports a location of one or more of the dispersed detectors that contribute to the detection.

The invention provides an ex-core nuclear detection system for a pressurized water reactor. The ex-core nuclear detection system is used for zero-power physics testing of reactors, and comprises an intermediate range detector and a reactivity meter, wherein the intermediate range detector is arranged outside a reactor pressure vessel and is used for measuring the nuclear power of the reactor; the reactivity meter calculates the reactivity of the reactor core according to data measured by the intermediate range detector; the reactive data can be used for measuring an isothermal temperature coefficient and a control rod value. Therefore, data measured by the intermediate range detector is transmitted into the reactivity meter, a test with high flux fluctuation can be performed, the gamma noise influence is small, the system can be far away from a Doppler heating point, the measurement result is accurate, low leakage and a low-leakage loading scheme can be implemented, the economic efficiency of fuel utilization is improved, and design of multi-reflection layer can be adopted, so that the economic efficiency and shock resistance of the fuel utilization are further improved, the measurement result is slightly influenced by spatial positions, and the influence of reactor cavity water injection transformation and the like because of RPN outward movement can be effectively reduced.

A correction for pileup of measurements made by a nuclear detector is applied by selecting the energy of the first signal in a pileup, ignoring the remaining signals in the pileup, and correcting the count rate by a factor related to the total pulse widths within a unit time interval. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

The invention discloses a digital nuclear detector state evaluation and guarantee maintenance method and system. The digital nuclear detector state evaluation and guarantee maintenance system gives a quantitative index for nuclear detector state evaluation and guarantee maintenance under the condition of not increasing an extra hardware circuit, and can realize on-line monitoring and make an effective expectation, thereby reducing service and maintenance cost of the nuclear detector, and improving reliability, stability and availability of the nuclear detector. The method is characterized by, to begin with, setting type attribute parameters of the detector; determining performance characteristic parameters to be evaluated of the detector; collecting data related to the performance characteristic parameters to be evaluated and generating list data; then, calculating the current performance characteristic parameters of the nuclear detector according to the list data; with the historical data being combined, analyzing and evaluating the current performance level and change trend of the nuclear detector to obtain the quantitative index of the current health state; and finally, making a guarantee maintenance auxiliary decision of the detector according to the quantitative index state.

For solving the technical problems that an existing presetting method for a focal plane of a detection camera is more trouble and low in efficiency, and cannot realize presetting of the focal plane ina vacuum environment, the invention provides a presetting device and a presetting method for the focal plane of the detection camera. The presetting device and the presetting method are characterizedin that defocusing distance of the detection camera is converted into that of a star simulator by using the conjugacy relation and the defocusing distance relationship between the star simulator andimaging of the detection camera; confusion spot images, acquired by the detection camera, of the star simulator at different defocusing distances, are analyzed to obtain imaging characteristics of thedetection camera at different defocusing distances, so that motion of a focal plane component of the detection camera is avoided, multiple fixation and adjustment of the posture of the focal plane component of the detection camera are not needed, and the testing efficiency is improved; the detection camera is arranged in a vacuum tank. The imaging characteristics of confusion spots of the detection camera under vacuum conditions are assessed by using the presetting device and the presetting method disclosed by the invention, and further focal plane presetting in the vacuum environment can berealized.

The invention discloses a nuclear detection device which comprises a flicker unit, a micro-optics unit, a photovoltaic conversion device and an image collecting and data processing unit, wherein the flicker unit is made of organic or inorganic crystals or thin film materials and is used for converting incidence beams into flicker light, and the converted flicker light is radiated to the micro-optics unit; a unit lens is used for generating a unit image of an object and the image is received by the photovoltaic conversion device; the photovoltaic conversion device is used for converting the received unit image into a two-dimensional data electric signal and transmitting the unit image to the image collecting and data processing unit; and the image collecting and data processing unit is used for acquiring, storing and processing the two-dimensional data electric signal obtained by the photovoltaic conversion device, and carrying out data reconstruction according to an optical path structure of the device so as to obtain the position that a photon is generated in the flicker unit. With the adoption of the device, the requirements on the flicker materials are reduced, the three-dimensional information about the position that the flicker light is generated in the flicker materials is obtained directly, the position identification can be realized and at the same time energy identification ability is provided, so that the performance of the nuclear detection device is improved.

A correction for pileup of measurements made by a nuclear detector is applied by selecting the energy of the first signal in a pileup, ignoring the remaining signals in the pileup, and correcting the count rate by a factor related to the total pulse widths within a unit time interval. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

The invention belongs to the field of nuclear detection processing in nuclear technique exploration, in particular to a discrete cosine neural-network fuzzy noise reduction method for nuclear detection data, and aims to effectively reduce noise in gamma spectrum data. The method includes the steps: subjecting spatial data formed by nuclear detection signal data to discrete cosine transform to obtain frequency spectrum data in a discrete cosine domain; subjecting the nuclear detection data to filtering and inverse discrete cosine transform in the discrete cosine domain to obtain primary noise reduction result; establishing a neural network, inputting a sample by using the nuclear detection signal data as nodes in the neural network, and estimating parameters of a membership function in the neutral network by means of least squares back-propagation to obtain final noise reduction result output by the neural network. The method is capable of well recognizing noise signals, network model parameters are regulated and optimized according to noise signal features, the noise in the signal data is reduced effectively, and signal-to-noise ratio of the nuclear detection data is increased greatly.

The invention discloses a method for distributing wireless sensor nodes for nuclear pollution detection. A ground high-mobility mobile reconnaissance robot provided with mechanical arms serves as a platform, and nuclear detection wireless sensor nodes are carried to enter a nuclear pollution site. The nuclear detection wireless sensor nodes are taken out of a box by utilizing the mechanical arms and are arranged at a detection place, and a switch of the nuclear detection wireless sensor nodes is turned on for detection; after the nodes are distributed, far-end detection personnel can determine an area with the highest polluted degree according to a detection value of the nuclear detection wireless sensor nodes and control the robot to enter the area so as to find a pollution source; and after the detection task is ended, the robot returns to the previous node distributing position according to global position system (GPS) positioning, and the nodes are closed and recovered into the box one by one. By the method, the working efficiency of the nuclear detection in a wide-range polluted area is greatly improved, and the nuclear radiation pollution degree in the polluted area can be rapidly and accurately found out.

The invention discloses a digitalized intelligent nuclear detection counting device based on Bluetooth wireless communication network, which mainly comprises a central processor unit, a signal input processing unit, a liquid crystal display and keyboard interface unit, a USB interface unit, a Bluetooth communication unit, a calendar time unit, an acousto-optic warning unit and a power distribution supplying and managing unit. The central processor unit is realized by adopting a singlechip and is used as a control core of the whole device. The singlechip is connected with other units through input and output ports of the singlechip, and manages and controls information of other units. The nuclear detection counting device has high timing and counting precision as well as high reliability, realizes friendly user interactive function, realizes multi-point synchronous wireless network deploying measurement, has compact structure and lightness, is convenient to carry, and is suitable for moving measurement.

A glass-clad scintillation optical fiber and a preparation method thereof belong to the preparation and application of new scintillation optical fibers and relate to the field of preparation and application of scintillation materials. The outer cladding layer of the scintillation optical fiber prepared by the present invention adopts a low-content Si glass material, which effectively reduces the infiltration of Si atoms into the optical fiber core during the drawing process, and can simultaneously meet the requirements for drawing an optical fiber with a small size of tens of microns. The preparation method of the scintillation optical fiber of the present invention comprises the steps of prefabricated rod, optical fiber drawing and heat treatment. The scintillation optical fiber of the present invention has high optical performance, fast attenuation, high density and low cost, and can be applied to the fields of modern nuclear detection and medical space imaging equipment and the like.

The invention discloses a plastic scintillator microsphere applicable to the field of nuclear detection, and a preparation method and application thereof. The scintillator resin components comprise a matrix material, a scintillating substance and a wave shifter, the particle size of the plastic scintillator microsphere is smaller than or equal to 1mm, and more specifically, the matrix material of the plastic scintillator microsphere is formed by polymerizing an unsaturated matrix monomer containing an active group, and the matrix monomer is styrene or vinyl toluene. The scintillating substance is 2, 5-diphenyl oxazole, and the wave shifter is 1, 4-bis (5-phenyl oxazole) benzene or-bis-(sigma-methyl styryl) benzene. The microspheres disclosed by the invention have very good physical and chemical stability, and have the advantages of low raw material price, wide raw material source, simple and convenient preparation method and the like. The plastic scintillator provided by the invention can be applied to continuous monitoring of radioactivity of a solution, or can be applied to preparation of a liquid scintillation spectrometer.

The invention relates to a thickener underflow concentration detection system. The thickener underflow concentration detection system comprises an underflow pulp detection device, an underflow pulp diluting device and a diluted pulp detection device, wherein the underflow pulp detection device is connected with a bottom pipeline of a thickener and is used for discharging bottom pulp of the thickener and detecting the flow rate of the pulp, the underflow pulp diluting device is connected with the output end of the underflow pulp detection device and is used for diluting the pulp outputted by the underflow pulp detection device through addition of water and then outputting diluted pulp, one end of the diluted pulp detection device is connected with the output end of the underflow pulp diluting device while the other end thereof is connected with a settling area on the upper portion of the thickener, and the diluted pulp detection device is used for detecting the flow rate and the concentration of the pulp outputted by the underflow pulp diluting device and is used for delivering detected pulp into the thickener. The thickener underflow concentration detection system is capable of achieving real-time reliable non-nuclear detection of the high-concentration underflow pulp of the thickener without causing pulp loss and pollution to the surrounding environment.

The invention discloses an electric guide rail type nuclear detection and delivery device, comprising a storage component, an internal hollow part and a non-closed bottom part, wherein an internal road sign is stored; The push-and-drop assembly comprises a temporary storage cabinet, a limiting piece and a baffle plate, wherein the temporary storage cabinet is arranged directly below the storage component; Wherein the limiting member is arranged below the temporary storage cabinet, the baffle extends horizontally outward from the left side above the temporary storage cabinet, the width of the storage component is not less than the diameter of the road marker, not more than twice the diameter of the road marker, and the road marker is stored in the storage component in a column. The invention marks whether there is nuclear radiation pollution in the surrounding area by the monitors in the nuclear pollution monitoring vehicle using the automatic delivery road marking equipment, Effectively prevent workers from direct exposure to the nuclear accident area, avoid close direct contact with radiation sources, contamination of radioactive materials, to the maximum extent to ensure the safety of rescue workers in the nuclear contaminated area.

When constructing a nuclear detector module in a gantry, a plurality of overlapping light guide modules (10) are mounted to the gantry in a spaced-apart fashion, and a plurality of underlapping light guide modules (12) are mounted in between each pair of overlapping light guide modules (10). Each of the underlapping modules and the overlapping modules includes a scintillation crystal array (16) on an interior surface thereof, and a plurality of PMTs on an exterior surface thereof. Overlapping modules (10) have overlapping structures (22) that interface with underlapping structures (18) on the underlapping modules (12) and thereby eliminate a seam directly beneath PMTs that overlap the crystal arrays of both an overlapping module and an underlapping module. Optical grease is used to form a resilient grease coupling and reduce light scatter between the underlapping and overlapping modules.

The invention discloses a method for distributing wireless sensor nodes for nuclear pollution detection. A ground high-mobility mobile reconnaissance robot provided with mechanical arms serves as a platform, and nuclear detection wireless sensor nodes are carried to enter a nuclear pollution site. The nuclear detection wireless sensor nodes are taken out of a box by utilizing the mechanical arms and are arranged at a detection place, and a switch of the nuclear detection wireless sensor nodes is turned on for detection; after the nodes are distributed, far-end detection personnel can determine an area with the highest polluted degree according to a detection value of the nuclear detection wireless sensor nodes and control the robot to enter the area so as to find a pollution source; and after the detection task is ended, the robot returns to the previous node distributing position according to global position system (GPS) positioning, and the nodes are closed and recovered into the box one by one. By the method, the working efficiency of the nuclear detection in a wide-range polluted area is greatly improved, and the nuclear radiation pollution degree in the polluted area can be rapidly and accurately found out.

Being in use for shielding strong magnetic field (MF), the magnetic shielding device with multilaminar composite structure solves issue that the design of magnetic shielding photomultiplier is unable to shield strong MF. Using multilaminar composite structure, the magnetic shielding device includes three layers from outer to inner: silicon steel assembly as middle layer, alloy assembly as inner layer, and solenoidal inductor as outer layer. The solenoidal inductor generates MF opposite to outer MF so as to weaken strong MF greatly. With higher saturation of MF, the silicon steel assembly reduces outer MF to a few Gauss further. Possessing quite high magnetic permeability of weak MF, the alloy assembly in innermost layer reduces residual MF to lower than 0.001 Gauss being far lower than level of earth MF. The invention makes shielded photomultiplier operate normally under strong MF. The invention has wide application in technical areas of nuclear electronics and nuclear detection.

The invention relates to a detection method and a detection system for detecting the leakage of the inner cooling water of a converter station converter valve. The method comprises the steps of (1) sealing the isotopic tracing liquid in a cold-water liquid in a converter valve to uniformly mix the isotopic tracing liquid with the cold-water liquid in the converter valve; (2) arranging a nuclear detection counter inside the valve hall of the converter station so as to detect the tracing material in the air surrounding the converter valve. The detection of the tracing material shows the leakage of the inner cooling water inside the converter valve around the counter. Compared with the prior art, the detection method and the detection system are simple and ingenious. The problem that the leakage of the converter station converter valve is difficult to be found out timely can be effectively solved. Meanwhile, the safe and reliable operation of the converter station is greatly facilitated.

A patient on a bed is positioned within an imaging space defined by a view field of a signal detector for collecting imaging signals to be reconstructed into the images by using signal processing. The patient positioning system uses a nuclear detection device having a mechanism for generating nuclear radiation and detecting mechanism for detecting an incident nuclear radiation. The proximity units are comprised of modulated LED light sources emitting a carrier modulated light beam and a photo receiver. An analog / digital converter is used for receiving signals output by the photo receiver while a bandpass filter is used for selectively passing the carrier modulated light beam. A detector determines the presence or absence of the carrier modulated light beam. The absence or presence of the carrier modulated light beam determines the position of the patient.

The invention discloses a rotary semi-closed nuclear detection release device, comprising: a storage component, wherein the interior of the storage component is hollow, the bottom of the storage component is not closed, and road signs are stored in the storage component; and a push component comprising a power component and a baffle, wherein the baffle is arranged below the storage component to block the road signs from falling; wherein the power component is placed obliquely below the road signs to drive the baffle to rotate so as to control the number of road signs in the storage component;and the width of the storage component is not less than the diameter of each road sign and is not greater than the twice of the diameter of each road sign, and the road signs are stored in a column inthe storage component. According to the rotary semi-closed nuclear detection release device disclosed by the invention, the monitoring personnel in a nuclear pollution monitoring vehicle uses an automatic road sign release device to mark whether there is nuclear radiation pollution in the surrounding area, thereby effectively preventing the worker from directly exposing to a nuclear accident occurrence area, avoiding the direct contact with a radiation source at a close distance to be contaminated by radioactive substances, and maximally ensuring the personal safety of rescuers in the nuclearpollution area.

The invention relates to a rapid preparation method of a Ce:Cs2LiYCl6 crystal for gamma-ray and neutron dual detection. The rapid preparation method comprises the following steps of: taking CeCl3, CsCl, LiCl and YCl3 as raw materials, placing a mold on the raw materials, carrying out vacuumizing, introducing argon, and carrying out heating and melting to overheat, wherein at least one capillary channel is arranged below the mold for conveying molten raw material liquid to the upper surface of the mold and forming a solution film on the upper surface; and then putting down a seed crystal, and carrying out pulling growth of the crystal at a rate of 3-8mm / min, wherein the growth period of the crystal is 10-15 hours. The preparation method provided by the invention realizes the rapid growth ofcentimeter-level bulk crystals, and the prepared Ce:Cs2LiYCl6 crystal can be used as a gamma-ray and neutron detection materials and used in the fields of nuclear detection, homeland security and thelike.

The invention, which belongs to the technical field of nuclear detection, relates to a positron annihilation angle correlation measurement device and method based on a positioning algorithm, thereby solving a problem that the measurement precision in the prior art is limited by the equipment precision. The device comprises a first fixed detector and a second fixed detector, a coincidence module, apositioning system, and a coincidence system. The first fixed detector and the second fixed detector are respectively used for detecting fluorescence signals generated by first gamma photons and second gamma photons which are generated by annihilation of electrons and positron in a sample and are propagated along a reverse direction; the coincidence module is used for processing the fluorescencesignals to obtain a first two-dimensional array and a second two-dimensional array which correspond to each other; the positioning system is used for obtaining incident position information of the first gamma photons and the second gamma photons according to the two-dimensional array; and the coincidence system is used for collecting incident position information of the first gamma photons and thesecond gamma photons within coincidence time, obtaining a corresponding three-dimensional annihilation angle in combination with the position information of the sample, and further obtaining a two-dimensional positron annihilation angle correlation spectrum. The defect that the measurement precision is limited by the precision of measurement equipment is overcome, and the measurement precision isimproved.

The invention discloses a Cherenkov event pulse digitization method and device, and belongs to the fields of event pulse detection systems, photoelectric signal processing and nuclear detection. The method comprises the following steps: S1, obtaining a data set of the of the Cherenkov event emission photons; S2, obtaining a data set of background light, S3, calculating a joint likelihood probability function or a posterior probability function of the data set of the Cherenkov event emission photons in each time period; S4, judging whether the data set of the background light in each time period is the data set of the background light or the data set of the Cherenkov event emission photons. The device comprises a Cherenkov event emission photon data set obtaining module, a background photondata set obtaining module, an independent photon correlator module and an event classifier module. The method and device are high in signal-to-noise ratio and spatial resolution.

The invention relates to the technical field of nuclear detection, and particularly discloses a processing method for a large-area annular plastic scintillator. The method comprises the following steps: S1: manufacturing the large-area plastic scintillator; S2: cutting the large-area plastic scintillator; and S3: polishing and aluminizing the large-area plastic scintillator. Performing irradiationmeasurement on a spot-shaped [beta]-plane radioactive source with a diameter of 2mm by the arge-area plastic scintillator manufactured by the method of which the response uniformity is three times better than the plastic scintillator obtained by using a general manufacturing method.

The invention discloses an open type field cage for improving the electric field uniformity, which relates to the technical field of nuclear detection, and can greatly reduce the distortion of the electric field in the field cage of a time projection chamber detector, expand the electric field uniformity area of the field cage and improve the performance of a time projection chamber. Through improving thefield cage electrode layout, the distortion area can be reduced to be less than 1 cm away from the edge of the field cage, and for a typical 10*10 cm<2> time projection chamber, the electric field uniform area in the field cage can be improved to be more than 8*8 cm<2> and accounts for more than 64% of the total effective area.

The invention relates to a radioactive source security monitoring and management system, provides the radioactive source security monitoring and management system based on practical needs, and aims to apply modern information management technologies such as a nuclear detection technology, a GPRS (general packet radio service) wireless data communication technology, 3G (3rd-generation) video and a large database to the radioactive source security monitoring and management system to realize the intelligent real-time monitoring and management of a radioactive source. The radioactive source security monitoring and management system comprises a radioactive source security monitoring and management terminal, accessory equipment and n site acquisition instruments, wherein n is an integer; the radioactive source security monitoring and management terminal is connected with the n site acquisition instruments through a GPRS network. According to the radioactive source security monitoring and management system, the radioactive source and a ray device are tracked and positioned by adopting a GPS (global positioning system) satellite positioning technology. The radioactive source security monitoring and management system is applied to industrial field and other related fields adopting radioactive sources.

The invention, which belongs to a nuclear detection technology, relates to a positron annihilation angle correlation measurement method, thereby solveing the problems of low feasibility, complex operation, low measurement efficiency and poor precision of an existing measurement method. The method comprises the following steps: respectively detecting incident position information of first gamma photons and second gamma photons which are generated by annihilation of electrons and positron in a sample and are propagated along a reverse direction by utilizing a plurality of first strip-shaped detection units of a first fixed detector and a plurality of second strip-shaped detection units of a second fixed detector; acquiring incident position information of the first gamma photons and the second gamma photons within the coincidence time, and obtaining a corresponding annihilation angle according to the incident position information and the position information of the sample; and acquiringa one-dimensional positron annihilation angle correlation spectrum according to the annihilation angle. The method is high in feasibility, the operation is simplified, and the measurement efficiency and measurement precision are improved.