59 results about "Neutron activation" patented technology

The present invention discloses a fusion reactor tungsten divertor structure design based on high temperature fused salt cooling. The fusion reactor tungsten divertor structure design comprises a tungsten surface pair plasma material and tungsten and lanthanum alloy heat sinks. The tungsten and lanthanum alloy heat sinks comprises a tungsten and lanthanum alloy heat sink 1 and a tungsten and lanthanum alloy heat sink 2. The tungsten and lanthanum alloy heat sink 1 is a half pipe with a C-shaped cross section, and the tungsten and lanthanum alloy heat sink 2 is a half pipe with a round angle and a semi-rectangle-shaped cross section. The tungsten surface pair plasma material is connected to the tungsten and lanthanum alloy heat sink 1, and the tungsten and lanthanum alloy heat sink 1 is connected to the tungsten and lanthanum alloy heat sink 2 to form a whole pipe. through the effective combination of tungsten and lanthanum alloy materials and a high-temperature fused salt cooling agent, the fusion reactor tungsten divertor structure design based on high temperature fused salt cooling is provided to adapt to a fusion reactor high-flux neutron irradiation environment, the heat bearing capacity can reach a 10-20MW/m2 steady-state thermal load, the structural material neutron activation is low, the , nuclear waste processing after component retirement is relatively easy, and the improvement of fusion reactor power generation economical efficiency is facilitated.

A method of determining structural defects in a component that utilizes neutron activation of a solution having the ability to penetrate small cracks on the surface of a material via capillary absorption that produces a discernable prompt gamma release of a defined energy when exposed to a neutron pulse. The intensity of the gamma rays produced at the desired energy at a user controlled position on the surface is used to determine the crack location, length and depth.

The present invention provides a nuclear activation apparatus for one or more fluid samples comprising the following modules;

• • a means for introducing one or more fluid samples to a sample conduit,
  • an activation thimble, comprising a section of sample conduit configured for multiple passes adjacent a radiation source,
  • an absorber located adjacent to the activation thimble, and
  • a detector located adjacent the sample conduit,

wherein the relative arrangement of the modules can be altered specific to an application and the rate of flow of the fluid sample adjacent the radiation source can be controlled.

The invention discloses a sample irradiation device for neutron activation. The sample irradiation device comprises a controller, a speed reducer, an irradiator, a vacuum tank, a compressed air tank and a gamma ray detector, wherein the speed reducer and the irradiator are arranged up and down and are fixedly connected; the irradiator is respectively connected with the vacuum tank and the compressed air tank; the gamma ray detector is fixedly connected with the irradiator; the speed reducer, the irradiator and the gamma ray detector are respectively and electrically connected with the controller. The sample irradiation device for the neutron activation, disclosed by the invention, is used as one of important and key components of an online neutron activation sample transmission and analysis system, has the functions of reducing the speed of rapidly transmitted sample boxes, hovering activated samples, particularly irradiated overdose samples, in reactor pool water outside a reactor activity zone for cooling and discharging water accumulated at the bottom part of an irradiation pipe, is more beneficial for radiation protection of environment and staff and is good in running stability and running safety.

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.

The invention relates to a transmission type cement raw material on-line neutron activated sulfur alkali ratio analysis device and an analysis method. A measuring device is a gamma detector fixed between an upper belt and a lower belt, a neutron source is placed above the upper belt and above a cement raw material, neutrons are downwards irradiated on the cement raw material on the belt to generate action with nucleus in the cement raw material, the gamma detector transforms the received ray into a pulse signal and transmits the pulse signal to a multi-channel energy spectrum analyzer to be processed, the multi-channel energy spectrum analyzer uploads effective information to an upper computer, and the upper computer calculates the sulfur alkali ratio of the cement raw material according to the corresponding formula. The sulfur alkali ratio finally obtained by calculation is a ratio relation between SO3 content and the sum of K2O content and Na2O content, so the sulfur alkali ratio is not influenced by the total amount of the cement raw material on the belt; the overall shielding protection of the instrument adopts a two-layer structure, the inner layer is lead and the outer layer is polyethylene, so the use amount of the lead is reduced, and the cost and the weight of the instrument are reduced; and a detector shielding body adopts a two-layer structure, the outer layer is polyethylene and the inner layer is a cadmium plate, so the influence on the gamma detector by the neutrons is minimized, and the analysis precision of the instrument is improved.

The invention discloses a peak position similarity energy spectrum searching method for neutron activation element analysis. According to the peak position similarity energy spectrum searching method, files in a spectral form knowledge base are numbered, and index files are established according to peak position information, wherein each index file is a binary number with the number of digits equal to the number of spectral forms; according to the peak position information of an actually measured spectral form, corresponding Boolean operation is conducted on the index files, and a spectral form meeting a searching requirement is obtained from the spectral form knowledge base. By the adoption of the peak position similarity energy spectrum searching method, the spectral form with the peak position similar to that of the actually measured spectral form can be rapidly and accurately found from the spectral form knowledge base, and especially when the number of the spectral form files in the spectral form knowledge base is large enough and far larger than the total number of channels of the spectral form files, the peak position similarity energy spectrum searching method has remarkable advantages.

The invention discloses a transmission commutator for an activated sample. The transmission commutator comprises a motor, a cylinder, a lead screw, a sample loader and a support, wherein the sample loader is in a cylinder shape; the cylinder is horizontally and fixedly arranged on the support; the motor is fixedly connected with one side of the cylinder in the X axial direction; the lead screw and the sample loader are arranged in the cylinder; the circle center line of the sample loader and the axial lead of the lead screw are both superposed with the X axial lead of the cylinder; one end of the lead screw is in sliding connection with the wall of the cylinder through a bearing; the other end of the lead screw penetrates through the cylinder and is fixedly connected with a shaft of the motor; and the lead screw penetrates through the center of the sample loader and is in sliding connection with the sample loader. The transmission commutator for the activated sample, disclosed by the invention, is used as one of important and key parts in a transmission system for neutron activated samples; in-pile radiation of sample boxes and transfer of the sample boxes towards multiple working places after radiation can be realized by adopting one commutator, and the compactness of the transmission device for neutron activated sample boxes and the transmission efficiency of the sample boxes are favorably improved, and operation stability and the safety are high.

The invention discloses a method for gradually approximating a scale gamma energy spectrum high-energy region based on peak shape fitting. According to the method, a standard gamma source and gamma rays generated by neutron activation characteristic substances are gradually adopted for calibration; a simple energy spectrum is adopted to scale a low-energy section, then a low-energy section scale result is used to estimate a high-energy section peak position, a peak shape fitting method is adopted to determine a peak center, an energy scale range is continuously expanded, an interested high-energy section is gradually approached, and finally a channel address interval corresponding to the interested high-energy section is obtained. Compared with a traditional method that professionals recognize manual scales after multiple samples are activated at a time and complex gamma energy spectra are obtained, the method provides a set of self-adaptive processes and algorithms, automatic scale isachieved, the requirement for operators is reduced, and an application scene of neutron activation analysis is greatly expanded.

The invention discloses a speed reducer for conveying of a pile irradiation sample. The speed reducer comprises a sealing chamber, a speed reducing pipe, an exhaust pipe, a transmission mechanism anda plurality of spring mechanisms. The speed reducing pipe, the exhaust pipe, the transmission mechanism and the spring mechanisms are arranged in the sealing chamber; the speed reducing pipe and the exhaust pipe are arranged vertically; the two ends of the speed reducing pipe and the lower end of the exhaust pipe penetrate out of the sealing chamber and airtightly and fixedly connected with the sealing chamber; the upper end of the exhaust pipe is communicated with the upper part of the speed reducing pipe; the spring mechanisms are arranged on the speed reducing pipe; the transmission mechanism is arranged on the speed reducing pipe and the exhaust pipe; and a plurality of strip-type openings are vertically formed in the speed reducing pipe. The speed reducer for the conveying of the pileirradiation sample, as one of important and critical components of a neutron activation sample conveying system, can effectively reduce the speed of a quickly moving sample box, has the characteristics of compact structure and good sample box speed reducing effect, has a protective effect on the safety of the sample box and a conveying device and operates safely and reliably.

The invention relates to a target material for a neutron line generation device, which is high in strength, good in radiation damage resistance and small in radioactivity after being activated by neutrons, foaming can be inhibited, the heat dissipation performance of the target material is improved, and the service life of the target material is prolonged. According to the target material for the neutron line generation device, the target material comprises an acting layer and a heat conduction layer, the acting layer can act with incident particle lines to generate neutron lines, the heat conduction layer supports the acting layer, the heat conduction layer is made of a metal-based graphene nano composite material, and the metal-based graphene nano composite material is a metal-based graphene nano composite material. The thermal conductivity of the metal-based graphene nano composite material is improved by more than 20% relative to that of the metal matrix.

The invention discloses an automatic sample injecting device for neutron activation, which includes a controller, a commutator, a sample injector I, a sample injector II, a sample injector III, a gas tank, an air compressor, and a stand. The sample injector I and the sample injector III, the commutator and the sample injector II, and the gas tank are respectively and fixedly arranged in the upper, middle and bottom layers of the stand. The sample injector I, the sample injector II and the sample injector III are connected with the commutator through a sample conveying tube. The commutator, the sample injector I, the sample injector II and the sample injector III are connected with the gas tank through pipes. The gas tank is connected with the air compressor through a pipe. The commutator, the sample injector I, the sample injector II, the sample injector III and the air compressor are electrically connected with the controller. The automatic sample injecting device for neutron activation has the characteristics of compact structure and less vibration and noise during operation. With the device, a large batch of samples can be injected in an automatic and orderly manner under programmed control. The device has good stability and safety.

The invention discloses a marker selection method for oil field logging. The method comprises the following steps of (a) selecting elements capable of participating in neutron activation treatment, and calculating element factors S of the selected elements according to the following formula (1): S=[theta]*[sigma]*[beta]*[gamma]/M(1); and (b) sorting the elements in a sequence from large S factors to small S factors according to the determination result in the step a, and primarily selecting the elements which are sorted in the front; then performing gamma ray interference elimination in the primarily selected elements, i.e., only remaining the elements with the large S factors in the elements with the characteristic gamma ray signal mutual interference; and regarding the finally left elements as marked elements. The invention provides a brand-new marker selection method; and through cooperation with the trace analysis, the flow rate of produced liquid in each target position under a well and the proportion of water to crude oil in the produced liquid can be accurately reduced. Meanwhile, the normal operation state of a horizontal well cannot be damaged, system errors can be effectively reduced, and the accuracy and reliability of the measurement result are improved.

A neutron activator for neutron activation of a material, the neutron activator being configured to produce neutrons from an interaction with a proton beam (7), the neutron activator comprising:

• • a neutron source comprising a metallic target (1), and
  • a Beryllium first reflector-moderator (4) peripheral to the neutron source and comprising a neutron activation area (10) configured to accommodate the neutron source and the material to be activated, the neutron activation area (10) of the first reflector-moderator (4) comprising a bore configured to accommodate the neutron source.

The invention discloses a device for detecting French chalk content in flour, and belongs to the field of nuclear technology application. The device utilizes a neutron activation principle to irradiate the flour with neutrons with energy of 14 MeV, short-lived radionuclide 28Al and 24Na are generated by the reaction between the neutrons and 28Si and 24Mg which are the main elements in French chalk(Mg3[Si4O10](OH)2), and by measuring delayed characteristic gamma rays released by the 28Al and 24Na, whether or not the flour contains French chalk is determined and the specific French chalk content is calculated. The device can penetrate the surface of the tested flour to measure the French chalk content of the inside, compared with chemical detection, the speed is fast, no sampling is needed,and the device can be directly installed on a transport belt, is suitable for real-time online detection, and has high detection precision, low detection limit, long-term measurement stability and strong anti-interference ability.

The embodiment of the invention provides a nuclear emergency dose card and a nuclear emergency dose measuring method. The nuclear emergency dose card comprises a main body (1), a measuring unit (2), and an identification unit (3). The identification unit (3) is arranged at the upper surface of the main body (1); an opening is formed in the lateral surface of the main body (1); and the measuring unit (2) is inserted into the main body (1) through the opening. The measuring unit (2) is used for measuring the neutron personal dose by a metal neutron activation sheet. Therefore, the personal doseof radiation can be recorded or traced; quick classification management of the personnel is implemented effectively; the radiation dose level received by the first responder is controlled; and the necessary radiation dosimetry information is provided for follow-up radiation damage treatment.

The invention discloses a digital imaging plate for neutron photography nondestructive testing of a radioactive sample, a manufacturing method of the digital imaging plate and a radioactive sample neutron photography nondestructive testing method. The digital imaging plate comprises a substrate and a digital imaging plate imaging film arranged on the substrate. The digital imaging plate imaging film includes a cured adhesive bonded to the substrate, pure metal powder and barium fluorobromide crystals, wherein the pure metal powder and the barium fluorobromide crystals are dispersed in the adhesive. The barium fluorobromide crystals in the digital imaging plate can be continuously exposed through secondary particles released by continuous decay of pure metal powder activated by transmission neutrons in the digital imaging plate, so that recorded neutron beam intensity distribution information of a transmission sample is recorded in the barium fluorobromide crystals; a digital imaging plate scanner is used for scanning the digital imaging plate to obtain neutron photographing detection imaging of the radioactive sample, the process of transferring a neutron conversion screen to a darkroom and making the neutron conversion screen closely contact with a film or the digital imaging plate is omitted, and the precision of the imaging data intensity of the digital imaging plate is improved.

The present invention relates to a glass microphere with pure beta-rays capable of producing action for curing carcinoma after having been activated and its preparation process. It is made up by using glass microsphere with pure beta-rays and anticorrosive coating layer applied onto external surface of the glass microsphere by adopting sol-gel method. The advantages of said invention lies in that the radioisotope in not easy to be penetrated into blood, the external physiological simulation liquid soaking test shows that the resolution of its correspondent nuclein is reduced by 1-2 orders of magnitude as compared with resolution of nucleic of microsphere without anticorrosive coating layer, it has no radioactive pollution, and its chemical stability is high. Said invention is simple in preparation process, its operation is safe and reliable, can be extensively used for radiotherapy to cure carcinoma.