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36 results about "Slow neutron" patented technology

Slow neutron. A neutron that is in thermal equilibrium with the surrounding medium, especially one produced by fission in a nuclear reactor, and slowed by a moderator.

Time-resolved, optical-readout detector for neutron and gamma-ray imaging

An efficient, large-area-detector and readout-system for combined sub-mm spatial imaging and time-of-flight spectrometry of fast and slow neutrons, as well as gamma-rays, capable of loss-free operation in mixed neutron-gamma fields of very high intensity.
Owner:STATE OF ISRAEL - SOREQ NUCLEAR RES CENT

Optical fiber coupled radiation detector used for slow neutron measurement

The invention relates to the radiometric technology and in particular to an optical fiber coupled radiation detector used for slow neutron measurement. The optical fiber coupled radiation detector used for the slow neutron measurement comprises a scintillation probe which is formed by blending of slow neutron sensitive materials and scintillating mediums, a transmission optical fiber and a photovoltaic sensitive component, wherein one end of the transmission optical fiber is inserted in the middle of the scintillation probe, the other end of the transmission optical fiber is connected with the photovoltaic sensitive component, and an optical wrapping layer of one part, arranged in the scintillation probe, of the transmission optical fiber is removed. The optical fiber coupled radiation detector used for the slow neutron measurement has the advantages of being simple in structure, small in size, strong in environment adaptability, capable of achieving on line real-time monitoring and the like, and can meet the demand of slow neutron measurement under complex and severe environment.
Owner:CHINA INST FOR RADIATION PROTECTION

Method for acquiring neutron protective fabric by doping rare earth element

InactiveCN102995389AAddressing Radiation Protection IssuesEffective protectionPhysical treatmentRare-earth elementPre irradiation
The invention discloses a method for acquiring a neutron protective fabric by doping rare earth element. The method comprises the following steps: (1) a, conducting pre-irradiation treatment on a textile by electron beam or plasma, and grafting the rare earth nanometer powder to the treated textile; or b, doping a rare-earth nanometer powder or rare earth salt into the textile, and conducting co-irradiation on the textile by electron beam or plasma; and (2) finally baking to obtain the neutron protective fabric. The invention acquires the flexible neutron protective fabric by doping rare earth element; the neutron protective fabric can effectively prevent slow neutron, thermal neutron and intermediate neutron, and especially shows obvious effect on fast neutron protection. According to the invention, rare earth element is grafted onto the textile to realize the flexible neutron prevention; and the method has great significance to solve a problem of neutron radiation protection and improve the added value of textile and rare earth.
Owner:WUHAN TEXTILE UNIV

Slow neutron detection device

InactiveCN106199680AReduce drift distanceIncrease the average probability of crossing the thresholdElectric discharge tubesX/gamma/cosmic radiation measurmentSlow neutronElectron drift
The invention discloses a slow neutron detection device. The slow neutron detection device comprises a first slow-neutron conversion body, a second slow-neutron conversion body, a reading-out electrode wire set and a negative electrode wire set, wherein the reading-out electrode wire set and the negative electrode wire set are arranged between the first slow-neutron conversion body and the second slow-neutron conversion body. As a reading-out circuit is arranged between the two slow-neutron conversion bodies, and under the condition that the boundary dimension of a detector is invariable, the electron drift distance is reduced by one half, and the average over-threshold probability of signals is increased.
Owner:TSINGHUA UNIV +1

Slow neutron conversion body and slow neutron detector

The invention relates to a slow neutron conversion body and a slow neutron detector, and belongs to the field of slow neutron detection. The slow neutron conversion body comprises a base body, and the base body comprises a plurality of holes extending in a first direction, and insulating walls among the plurality of holes, wherein the holes are through holes. The slow neutron conversion body also comprises a boron layer which at least covers the exposed surfaces of the holes. The slow neutron conversion body and the detector can maintain higher slow neutron detection efficiency. In addition, the slow neutron conversion body and the detector can reduce the manufacturing complexity and cost of the detector, thereby achieving effective, convenient and low-cost slow neutron detection.
Owner:TSINGHUA UNIV +1

Preparation method for radioactivity TiNi alloy bracket without fringe effect

A preparation method for radioactivity TiNi alloy bracket without fringe effect relates to a preparation method for a radioactivity bracket. The preparation method solves the problem of high restenosis rate of the edge of the bracket caused by weak penetrating power of a pure <32>P ray and uniform dosage around the bracket. The method comprises the following steps of: 1. preparing a cast ingot, 2. preparing cold-drawn wires; 3 twisting cold-drawn wires into a bracket, heat processing in vacuum, chemical polishing, ultrasonic washing and drying; 4. putting the dried bracket into a plasma-based injection system for slow neutrons irradiation; 5. annealing the irritated bracket and then cooling the irritated bracket, thus obtaining the radioactivity TiNi alloy bracket. The radioactivity TiNi alloy bracket obtained by the invention both preserves the excellent superelasticity, good corrosion resistance and biomedical science performances of the alloy, also can obtain mixed rays dominated by <32> P, and improves the uniformity of the dosage distribution of the rays around the bracket and is beneficial to inhibiting the fringe effect.
Owner:HARBIN INST OF TECH

Ray radiation and neutron radiation protection material and preparation method thereof

The invention relates to the technical field of anti-radiation materials. The invention further discloses a ray radiation and neutron radiation protection material. The material comprises 20-30 partsof synthetic polyester, 5-8 parts of barium powder, 4-6 parts of bismuth borate, 4-8 parts of tungsten ore powder, 2-4 parts of barium sulfate, 10-16 parts of resin, 8-10 parts of tungsten ore powder,4-8 parts of a light element material, 2-4 parts of a lithium-containing material, 4-6 parts of boric acid, 6-10 parts of modified silicone rubber and 3-5 parts of an adhesive. Heavy elements of barium powder, tungsten ore powder and lead powder are arranged, according to the present invention, by arranging the light element material and the lithium-containing material, the slow neutrons can be well absorbed so as to achieve the good neutron protection effect, such that the good protection effect on the ray radiation and the neutron radiation is provided, and the good radiation resistance isprovided.
Owner:山东杰创安全检测有限公司

Neutron composite detection device

The invention relates to the technical field of radiation measurement, and specifically discloses a neutron composite detection device. The neutron composite detection device comprises an aluminum shell, a magnesia powder layer arranged on the inner side wall of the aluminum shell, plastic scintillators arranged on the inner side of the magnesia powder layer, <6>LiI(Eu) scintillators arranged on the inner side of the plastic scintillators, and quartz glass arranged above the aluminum shell, the magnesia powder layer, the plastic scintillators and the <6>LiI(Eu) scintillators. The neutron composite detection device can be directly coupled with a photomultiplier, can be used as a neutron detector capable of measuring fast neutrons and slow neutrons with the addition of an appropriate electronic circuit, and the detector does not need to additionally arrange a moderator structure on the outside, thus the neutron composite detection device has great advantages in size and weight, and is convenient for the operator to use.
Owner:CHINA NUCLEAR CONTROL SYST ENG

Noble-gas-excimer detectors of slow neutrons

The present invention relates to apparatus and methods for use in highly sensitive and efficient neutron detection, that includes using trigger reactions to initiate far-ultraviolet (FUV) optical emissions. In some embodiments of the present invention, a method for the detection of slow neutrons includes absorption of a slow neutron with a high neutron capture-cross-section nucleus, decay of the compound nucleus into energetic particles, creation of excimers from the energetic particles reacting with a background gas to form excimers, radiative decay of excimers resulting in emission of FUV radiation, and detection of the FUV radiation using an optical detector.
Owner:GOVERNMENT OF THE UNITED STATES OF AMERICA AS REPRESENTED BY THE SEC OF COMMERCE THE NAT INST OF STANDARDS & TEHCNOLOGY

Elemental analysis device combined with neutron-activation instant and delayed gamma rays

The invention discloses an elemental analysis device combined with neutron-activation instant and delayed gamma rays, and belongs to the field of the application of nuclear technology. The elemental analysis device is used for measuring an inelastic scattered instant characteristic gamma energy spectrum of a sample in a combinational manner by using a fast neutron source and a lanthanum bromide detector, measuring a neutron captured instant characteristic gamma energy spectrum in the combinational manner by using a slow neutron source and a high-purity germanium detector and finally measuringa neutron-activation delayed characteristic gamma energy spectrum in the sample by using a sodium iodide detector. Relative to a conventional neutron-activation elemental analysis device, the elemental analysis device provided by the invention not only utilizes instant characteristic gamma rays generated by neutron activation, but also collects delayed characteristic gamma rays; relative to the instant rays, delayed rays have a small quantity, however, are not interfered by a neutron, and further, seldom has the superposition of characteristic peak positions of gamma rays; a specific element is conveniently and accurately analyzed and calculated. A fast neutron and a slow neutron irradiate the sample respectively to increase an irradiation time, and the generation efficiency and the collection efficiency of inelastic scattered gamma rays and neutron captured gamma rays are improved.
Owner:JILIN UNIV

Method for obtaining neutron shielding fabric by doping rare-earth element

InactiveCN109667136AAddressing Radiation Protection IssuesEffective protectionPhysical treatmentRare-earth elementSlow neutron
The invention discloses a method for obtaining neutron shielding fabric by doping a rare-earth element. The method comprises the following steps: (1) a, performing electron beam or plasma pre-irradiation treatment on a textile, and grafting the rare-earth nano powder onto the treated textile; or b, doping rare-earth nano powder or rare-earth salt in the textile, and co-radiating the textile through the electronic beam or the plasma; and (2) finally baking to obtain the neutron shielding fabric. The flexible rare-earth neutron shielding fabric obtained by doping the rare-earth element is effective in shielding slow neutrons, thermal neutrons and intermediate-energy neutrons, and is obviously effective in shielding quick neutrons. The rare-earth element is grafted onto the textile, so that flexible neutron shielding is realized, and therefore, great significance is achieved for solving the neutron radiation shielding problem and improving the textile and rare-earth additional value.
Owner:余姚市荣欣毛麻制品厂

Apparatus and method for detecting slow neutrons by lyman alpha radiation

A method and apparatus for detecting slow neutrons by monitoring Lyman alpha radiation produced by the 3He(n,tp) nuclear reaction induced by neutrons incident on a gas cell containing 3He or a mixture of 3He and other atoms and / or molecules. Such a method and / or apparatus includes the use of, for example, liquid 3He and 4He mixtures as a scintillation counter for the sensitive detection of neutrons using Lyman alpha radiation produced by the 3He(n,tp) reaction. The radiation can be detected with high efficiency with an appropriate photo-detector, or alternatively, it can be converted to radiation at longer wavelength by absorption in scintillation materials, with the radiation channeled to a photodetector. Because of the simplicity of the system and the fact that the radiation production mechanisms can be measured and / or calculated independently, the method and / or apparatus also has the potential for service as a calculable absolute detector.
Owner:THE UNITED STATES OF AMERICA AS REPRESENTED BY THE SECRETARY OF THE COMMERCE

Fast and slow neutron combined detector

ActiveCN108152851AHigh sensitivitySensitivity adjustment is flexibleMeasurement with scintillation detectorsLithiumAdhesive
The invention relates to a fast and slow neutron combined detector, which is characterized in that the main structure is a cylindrical plastic scintillator, the plastic scintillator is internally provided with blind holes, and the blind holes are uniformly arranged in a layered manner; lithium glass scintillation columns are placed in the blind holes, a contact surface of each lithium glass scintillation column and the plastic scintillator is coupled by using an optical coupling agent; a light window surface of the plastic scintillator adopts polishing treatment, and the other outer surfaces are subjected to grinding treatment; the plastic scintillation is coated with a reflecting layer except for the light window surface, and the reflecting surface is externally covered by a shell; and the light window surface of the plastic scintillation is packaged with a light window by adopting an optical adhesive, the light window serves as a light leading-out surface, and the scintillation lightis led out by the light window. The plastic scintillator is used for measuring incident fast neutrons, the lithium glass adopts a multilayer structure, the number of lithium glass scintillation columns in each layer increases layer by layer from the inside out, and number of layers is preferably to be three. The outer layer and the inner layer are used for detecting incident slow neutrons, the inner layer and the central lithium glass can measure the slow neutrons slowed down by the plastic, and the sensitivity of the incident fast neutrons and the sensitivity of the slow neutrons are improved at the same time.
Owner:CHINA NUCLEAR CONTROL SYST ENG

Personal wearable dosimeter for neutrons

SUMMARYThe invention relates to a dosimeter (A) wearable by a human subject which includes:at least a first slow neutron sensor S1; a matrix containing a certain amount of absorbent material for slow neutrons;at least a second slow neutron sensor S2; a moderator consisting of or comprising polyethylene, hydrogenated plastic, water, paraffin or other hydrogenated or deuterated compounds.
Owner:IST NAZ DI FISICA NUCLEARE

Diamond film and graphite composite material

The invention discloses a diamond film and graphite composite material, which is mainly used as a fusion device plasma facing material (PFMs). The diamond film grows on the surface of the graphite, and the diamond film and graphite composite material is formed. The diamond film and graphite composite material which is used as the fusion device plasma facing material (PFMs) has the advantages of small absorption of slow neutrons, good high-temperature strength, high thermal shock resistance, good deceleration performance towards fast neutrons, size stability under irradiation, little impurity content and high bulk density.
Owner:LANGFANG SUPOWER DIAMOND TECH

Neutron detection device and personal dosage alarm apparatus using same

The invention relates to a personal neutron dosage alarm apparatus, and the neutron dosage is calculated by detecting a ratio of scattering neutrons to incident neutrons. The alarm apparatus comprisesa neutron detection device, a processor connected with the detection device, and a power supply, a display screen, an LED indicating lamp, a buzzer, a memory, an infrared transmission unit and a functional keyboard. The neutron detection device comprises a detection system A, a detection system B and a thermal neutron shield, the detection system A and the detection system B are completely identical, the thermal neutron shield is used to absorb incident thermal neutrons and is designed in a cap shape; and the detection system A is arranged outside the thermal neutron shield and used to detectincident slow neutrons; and the detection system B is arranged inside the thermal neutron shield and used to detect neutrons reflected by the human body. The personal neutron dosage alarm apparatus is small in size, low in working voltage, and high in electromagnetic interference resistance, and can work in a high-humidity environment for a long time.
Owner:CHINA NUCLEAR CONTROL SYST ENG

Raman spectrum-based neutron radiation dose detection method

The invention discloses a Raman spectrum-based neutron radiation dose detection method, which comprises the steps of placing a converter material attached to the surface of a substrate in a slow neutron irradiation environment, exciting the converter material by utilizing a Raman laser, and measuring a Raman spectrum of the converter material after neutron radiation; and further, comparing the Raman spectrum after neutron radiation of the converter material with the characteristic peak offset of the Raman spectrum in the calibration dose table, and determining the neutron radiation dose in theslow neutron radiation environment. According to the embodiment of the invention, the Raman spectrum of the converter material in the neutron radiation environment is measured, and the characteristicpeak of the Raman spectrum is compared with the characteristic peak of the Raman spectrum in the calibration dose table to obtain the characteristic peak offset, so that the neutron radiation dose isdetermined, the sensitivity is high, and the detection efficiency is improved.
Owner:BEIJING INST OF SPACECRAFT ENVIRONMENT ENG

Method for TiNi alloy stent with phosphorus injection and slow neutron irradiation activation

InactiveCN101496907ASolve the problem of weak ray penetrationStentsProsthesisAlloySlow neutron
The invention discloses a method for irradiation and activation of slow neutrons after a TiNi alloy stent is injected with phosphorus, and relates to a method for phosphorus injection for the TiNi alloy stent. The method solves the problem that rays have weak penetrability after the TiNi alloy stent is injected with the phosphorus in the prior art. The method comprises the following steps of: 1, chemical polishing; 2, phosphorus injection; and 3, irradiation and activation of the slow neutrons; and the TiNi alloy stent injected with the phosphorus is obtained. The TiNi alloy stent which is prepared by the method and is injected with the phosphorus has strong ray penetrability. The method is simple and has convenient operation.
Owner:HARBIN INST OF TECH

Preparation method of ultra-fine fiber material for preventing neutron radiation

The invention provides a preparation method of an ultra-fine fiber material for preventing neutron radiation. A PP section and nano B4C blend is used as a raw material of the ultra-fine fiber material, a titanate coupling agent and TAS-2A are used as additives, and PP / B4C blend is subjected to melt spinning by melt blowing. A fast neutron slowing-down material (polypropylene) and a slow neutron absorbing material (nano boron carbide) are blended, on the basis of surface modification on the nano boron carbide by the titanate coupling agent, a TAS-2A dispersant is added, therefore, the nano B4C is uniformly adhered to the surface of a carrier, after PP / B4C masterbatches are prepared, the PP / B4C masterbatches and matrix sections are blended in proportion, melt spinning is carried out by melt blowing, the nano boron carbide are uniformly dispersed into polypropylene ultra-fine fibers, the prepared ultra-fine fiber net-shaped material is soft, fluffy, light and thin and is good in breathability, and then protective garment of which the protective shielding rate to thermal neutrons can reach 80% is manufactured.
Owner:HENAN INST OF ENG

Method for measuring double-ended water content

A method of using two ends to measure water content includes applying two slow neutron detectors on neutron analyzing device, reasonably locating detection positions of two slow neutrons according to slow neutron space distribution in layering of water content on material and using couple-counting of two slow neutron detectors to carry out measurement of water content.
Owner:DANDONG DONGFANG MEASUREMENT&CONTROL TECHCO

Bendable and foldable organic silicon rubber with high neutron shielding effectiveness and preparation method thereof

The invention discloses bendable and foldable organic silicon rubber with high neutron shielding effectiveness and a preparation method thereof. According to the method, 110 silicone rubber is used as base rubber, fumed silica, nuclear power grade B4C powder or a foaming agent is added, and hot-pressing vulcanization molding is performed under the action of a vulcanizing agent. According to different components of the material, the neutron shielding rate of the boron silicon rubber can reach 99.9% or above for fast neutrons, medium energy neutrons or slow neutrons. The organic silicon rubber can be widely applied to spallation neutron source, nuclear facility pipeline neutron protection and neutron radiation field personnel protection; meanwhile, the material is simple in preparation process and can be subjected to continuous extrusion molding.
Owner:INST OF CHEM MATERIAL CHINA ACADEMY OF ENG PHYSICS

Paraffin/boron carbide neutron protection composite material and preparation method thereof

The invention discloses a paraffin / boron carbide neutron protection composite material and a preparation method thereof, belongs to the technical field of nuclear protection materials, and solves the problems of incompact structure, boron carbide sedimentation and agglomeration and the like during preparation by adopting a casting method in the prior art. According to the preparation method of the paraffin / boron carbide neutron protection composite material, the content of paraffin in the neutron protection composite material is 1-60wt%, and the balance is boron carbide; and the neutron protection composite material is prepared by adopting a cold isostatic pressing method. Paraffin and boron carbide are creatively adopted as raw materials, and the neutron protection composite material is prepared through the cold isostatic pressing method. The paraffin / boron carbide neutron protection composite material disclosed by the invention is uniform in boron carbide distribution, compact in structure and excellent in performance, can have double functions of slowing down and absorbing of fast neutrons, slow neutrons and thermal neutrons, and meets neutron protection requirements of special occasions of spent fuel post-treatment.
Owner:MATERIAL INST OF CHINA ACADEMY OF ENG PHYSICS

Water-cooling gadolinium-containing lined adhesive neutron shield glass

ActiveCN106746758ANovel structureImprove neutron radiation resistanceGlass/slag layered productsAdhesiveGadolinium
The invention relates to a water-cooling gadolinium-containing lined adhesive neutron shield glass, and belongs to the technical field of glass. The water-cooling gadolinium-containing laminated neutron shield glass comprises a glass sheet 1, a glass sheet 2 and a lined adhesive, wherein the lined adhesive is arranged between the glass sheet 1 and the glass sheet 2; the glass sheet 1 is a whole inorganic glass sheet which is formed by hotly pressing a thin glass sheet 1, a thin glass sheet 2 and a thin glass sheet 3; through holes are formed in the glass sheet 1 for water to pass through, and the two layers of through holes are uniformly staggered and distributed in the glass sheet 1; metal particles (gadolinium) are arranged in the lined adhesive; the glass sheet 2 is a gadolinium-contained organic glass; the glass sheet 1 and the glass sheet 2 are adhered into a whole by the lined adhesive. The water-cooling gadolinium-containing laminated neutron shield glass has the advantages that in the use process, the water is filled into the through holes; the structure can slow the neutron penetrating through the glass plane, and the quick neutron is changed into the slow neutron; by arranging the metal particles (gadolinium) in the lined adhesive, the neutrons can be further absorbed; by arranging the metal particles (gadolinium) in the glass sheet 2, the neutron radiation can be absorbed for the second time, and the anti-neutron radiation ability in transparent material is effectively improved.
Owner:YANGZHOU UNIV

Preparation method of composite tubular part for moderating neutrons in nuclear reactor

The invention relates to preparation of nuclear radiation protective materials, in particular to a preparation method of composite material tube-shaped parts used for a nuclear reactor moderated neutron. For solving the problem that for an existing preparation method of the composite material tube-shaped parts used for the nuclear reactor moderated neutron, the technological process is relativelycomplicated, and meanwhile, shaping of the tube-shaped parts adopts a welding technology, so that the made tube-shaped parts are not good enough in performance, the preparation method of the compositematerial tube-shaped parts used for the nuclear reactor moderated neutron adopts a spark plasma sintering technique to prepare an aluminum base graphite composite material blank. Mechanical processing is conducted on the aluminum base graphite composite material blank prepared through sintering. More than one time of spinning forming is conducted on the aluminum base graphite composite material blank after mechanical processing by using a method of strong spinning, and finally, a thin-walled tube-shaped part is formed by spinning. Spinning is beneficial for improving mechanical properties such as density, strength and hardness of the composite materials, and meanwhile the using ratio of the materials is improved, and the manufacturing cost is reduced. A prepared finished product can be used for spent fuel storage as well as a nuclear power station middle tube-shaped shielding body and the preparation method of the composite material tube-shaped parts used for the nuclear reactor moderated neutron is an advanced method for preparation of the composite material tube-shaped parts.
Owner:TAIYUAN UNIV OF TECH

Neutron radiation-resistant polyimide coating and preparation method and application thereof

The invention relates to a neutron radiation-resistant polyimide coating and a preparation method and application thereof. The preparation method comprises the following steps: reacting cyanoborane-containing triamine with an anhydride-terminated polyimide oligomer to obtain hyperbranched polyimide, and ball-milling and blending a functional slow neutron adsorption compound, a silane coupling agent and the hyperbranched polyimide. The method is simple to operate, environmentally friendly in process, and beneficial to mass preparation, and has good industrialization prospect. The obtained coating has excellent neutron radiation prevention effect, good heat resistance and interfacial adhesion, can further generate crosslinking reaction in radiation and thermal environments, and can be applied to extreme environments such as nuclear radiation or special environments.
Owner:DONGHUA UNIV

A water-cooled gadolinium-containing interlayer neutron shielding glass

ActiveCN106746758BNovel structureImprove neutron radiation resistanceGlass/slag layered productsAdhesiveGadolinium
The invention relates to a water-cooling gadolinium-containing lined adhesive neutron shield glass, and belongs to the technical field of glass. The water-cooling gadolinium-containing laminated neutron shield glass comprises a glass sheet 1, a glass sheet 2 and a lined adhesive, wherein the lined adhesive is arranged between the glass sheet 1 and the glass sheet 2; the glass sheet 1 is a whole inorganic glass sheet which is formed by hotly pressing a thin glass sheet 1, a thin glass sheet 2 and a thin glass sheet 3; through holes are formed in the glass sheet 1 for water to pass through, and the two layers of through holes are uniformly staggered and distributed in the glass sheet 1; metal particles (gadolinium) are arranged in the lined adhesive; the glass sheet 2 is a gadolinium-contained organic glass; the glass sheet 1 and the glass sheet 2 are adhered into a whole by the lined adhesive. The water-cooling gadolinium-containing laminated neutron shield glass has the advantages that in the use process, the water is filled into the through holes; the structure can slow the neutron penetrating through the glass plane, and the quick neutron is changed into the slow neutron; by arranging the metal particles (gadolinium) in the lined adhesive, the neutrons can be further absorbed; by arranging the metal particles (gadolinium) in the glass sheet 2, the neutron radiation can be absorbed for the second time, and the anti-neutron radiation ability in transparent material is effectively improved.
Owner:YANGZHOU UNIV
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