24 results about "Epithermal neutron" patented technology

The invention provides a mountain freeze-thaw desertification early warning method and related equipment. The method comprises the following steps: acquiring thermal neutron intensity and epithermal neutron intensity of a target area; based on a target intensity ratio and a pre-obtained empirical fitting parameter set, target parameters are determined, and the target intensity ratio is the ratio of the thermal neutron intensity to the epithermal neutron intensity of the target area; determining a target moisture content according to the target parameter and the thermal neutron intensity or epithermal neutron intensity of the target area; and when the target moisture content is lower than a preset critical soil moisture threshold value, carrying out mountain freeze-thaw desertification early warning. Soil moisture is inverted through a cosmic ray neutron detection technology, environmental interference factors such as a non-soil water hydrogen source are corrected, local soil moisture of different vegetation types and soil types is accurately captured, freeze-thaw desertification is judged in combination with a critical soil moisture threshold, and early warning is given.

The present invention relates to a cyclotron comprising first and second internal ion sources configured to form first and second beams of identical charged particles wherein the cyclotron is further configured to generate a local asymmetry of an accelerating electric and / or magnetic field, the first beam and the second beam are combined to form a combined beam and the combined beam passes through a single extraction outlet. The invention also relates to an acceleration system comprising N cyclotrons, where M cyclotrons are the cyclotrons according to the invention, Mgt; 0. The invention also relates to a device for treating a patient by BNCT, comprising: an acceleration system according to the invention; a target configured to emit an epithermal neutron beam when bombarded with the proton or deuteron multi-combination beam; and a treatment region configured to hold a patient to be treated within the treatment region.

The invention discloses a uranium mine logging instrument based on ultrashort pulse neutrons and a working method thereof, and relates to the field of uranium mine exploration logging. The logging instrument comprises a control communication short section, an ultrashort pulse neutron generator used for emitting fast neutron pulses with the pulse width smaller than 1 microsecond to a stratum, a shielding body and a double-thermal-neutron detection assembly used for detecting thermal neutrons and epithermal neutrons on measuring points consistent in space, all of which are sequentially arranged in the axial direction of the logging instrument. The gamma detector is used for detecting inelastic scattering gamma rays emitted by stratum elements and capturing gamma rays, and the fast neutron detector is used for detecting and outputting source intensity monitoring signals of fast neutron pulses in real time. According to the logging instrument, the ultra-short fast neutron pulse is emitted, the neutron yield is detected in real time, the neutron time spectrum and gamma-ray energy spectrum multi-dimensional information with an accurate timestamp are obtained in a combined mode, high-precision and anti-interference inversion is conducted on the stratum uranium content, and stratum information is obtained efficiently and accurately.

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.

Alkylphosphocholine analogs incorporating a chelating moiety that is chelated to gadolinium are disclosed herein. The alkylphophocholine analogs are compounds having the formula:or a salt thereof. R1 includes a chelating agent that is chelated to a gadolinium atom; a is 0 or 1; n is an integer from 12 to 30; m is 0 or 1; Y is —H, —OH, —COOH, —COOX, —OCOX, or —OX, wherein X is an alkyl or an arylalkyl; R2 is —N+H3, —N+H2Z, —N+HZ2, or —N+Z3, wherein each Z is independently an alkyl or an aroalkyl; and b is 1 or 2. The compounds can be used to detect solid tumors or to treat solid tumors. In detection / imaging applications, the gadolinium emits signals that are detectable using magnetic resonance imaging. In therapeutic treatment, the gadolinium emits tumor-targeting charged particles when exposed to epithermal neutrons.

The invention discloses a single-source multi-beam boron neutron capture therapy system, and relates to the field of radiotherapy equipment. The system comprises a set of low-energy proton accelerator, an electromagnetic field steering part and two or more treatment rooms, wherein each treatment room is provided with a corresponding target material and a neutron moderation device. The method comprises the following steps of: guiding proton beams to respectively bombard a plurality of target materials to generate fast neutrons through an electromagnetic field steering part by utilizing the electrification characteristic of protons, moderating the fast neutrons into thermal neutrons (suitable for superficial tumors) or epithermal neutrons (suitable for deep tumors) through a neutron moderating device made of a hydrogen-containing or fluorine-containing moderating material, and guiding the thermal neutrons or epithermal neutrons to a corresponding treatment room. Through a single-source multi-beam architecture, multi-energy neutron beam output and multi-patient parallel treatment are realized on the basis of one set of accelerator, the treatment adaptation disease range is greatly expanded, the equipment cost and the occupied area are reduced, and the treatment flexibility and the equipment utilization rate are improved.

The embodiment of the specification provides a neutron flux determination method and device applied to samarium-neodymium isotope system dating, wherein the neutron flux determination method applied to the samarium-neodymium isotope system dating comprises the following steps: performing isotope measurement on a sample to determine isotope measurement data of the sample; performing simulation on a neutron irradiation effect of the sample to determine neutron irradiation model data; comparing the isotope measurement data and the neutron irradiation model data to determine a comparison result; and determining the epithermal neutron flux based on the comparison result. The size of the epithermal neutron flux is obtained by simulating the isotope data of the sample, the method is widely applicable, and can be used for drilling samples, return samples, meteorite samples and the like, thereby improving the accuracy of the dating results of isotope systems at different depths and providing a reliable basis for studying the drilling lunar soil sample turnover rate.

The invention discloses a neutron source based on an FRC linear magnetic confinement nuclear fusion device, and relates to the technical field of fusion devices. The neutron source comprises a vacuum chamber for providing a vacuum environment for fusion reaction; the magnet system is arranged outside the vacuum chamber and is used for ionizing gas in the vacuum chamber and generating fusion reaction; the neutron extraction system is arranged in the fusion reaction generation area of the vacuum chamber and is used for extracting epithermal neutrons; the neutron lead-out system comprises a neutron lead-out channel, a shielding and reflecting device and a filter, the shielding and reflecting device is arranged outside the lead-out channel and used for shielding and reflecting neutrons, and the filter is arranged in the neutron lead-out channel and used for filtering fast neutrons, thermal neutrons and photons; the neutron source provided by the invention has the advantages of higher neutron yield, simple and compact structure, effectively reduced overall device volume, low construction and maintenance cost and small nuclear safety prevention and control pressure, and can be used in various fields of medical treatment, scientific research, military industry and the like.

The invention discloses a same-position integrated double neutron detector, a logging instrument and an application method, and belongs to the field of uranium exploration logging. The double-neutron detector comprises a thermal neutron detector and an epithermal neutron detector which are arranged in a nested mode. The thermal neutron detector is arranged to be a first microstructure gas detector and comprises an annular cavity structure, a cathode drift electrode and an anode reading electrode, wherein the annular cavity structure is provided with an axial through hole and is filled with He gas. The detection part of the epithermal neutron detector is embedded in the axial through hole, and the epithermal neutron detector can be a scintillation crystal detector coated with a shielding moderation layer or a second microstructure gas detector. Compared with the prior art, the nested structure fundamentally solves the inherent problem of space inconsistency of a traditional separation detector, and the uranium content calculation precision is greatly improved; meanwhile, the epithermal neutron detector has two implementable schemes, and the structural flexibility is high.

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.

The present invention relates to the field of wireline logging technology, specifically disclosing a device and method for testing the mineral composition and content of uranium-bearing reservoirs. The device comprises a wireline logging system, a logging depth calibration system, and a time synchronization system. The logging tool assembly comprises a spectral logging tool, a natural gamma ray spectroscopy logging tool, an epithermal neutron logging tool, and a neutron capture gamma ray spectroscopy logging tool. The method comprises: combining the logging tool assembly with the wireline logging system, configuring a logging depth calibration system, configuring a time synchronization system, performing PTP time synchronization on the wireline logging system and the logging depth calibration system, collecting raw logging time and raw logging data, performing time resampling and depth correction on the raw logging data, and demarcating the formation structure based on the logging depth and time resampled logging data. The present invention enables the acquisition and data fusion of the mineral composition, radioactive element content, and porosity characteristics of the formation surrounding the wellbore, thereby improving exploration precision, efficiency, and evaluation accuracy.

This invention provides a uranium content detection method, device, storage medium, and electronic device, belonging to the field of mineral exploration technology. The uranium content detection method includes: acquiring well logging data, which includes hyperthermal neutron counts, thermal neutron counts, and macroscopic scattering cross-section information, obtained by logging after emitting pulsed neutrons into the well to be logged; calculating the formation uranium content based on the hyperthermal neutron counts, thermal neutron counts, and macroscopic scattering cross-section information using a pre-set formation uranium content calculation model, which is based on a numerical simulation model of uranium content, mineralization, and porosity conditions established using the Monte Carlo method. This method can eliminate the errors caused by formation porosity and mineralization in the uranium content calculation process, improving the accuracy of formation uranium content evaluation and the efficiency of uranium ore detection.

The application discloses a kind of uranium mine logging instrument based on ultrashort pulse neutron and working method thereof, it is related to uranium mine exploration well logging field;Logging instrument includes control communication nipple arranged in sequence along its axial direction, ultrashort pulse neutron generator for emitting fast neutron pulse with pulse width less than 1 microsecond to formation, shielding body, dual thermal neutron detection assembly for detecting thermal neutron and superhot neutron on spatially consistent measurement point, gamma detector for detecting non-elastic scattering gamma ray and capture gamma ray emitted by formation element, and fast neutron detector and multichannel synchronization and high-speed acquisition circuit for detecting and outputting source intensity monitoring signal of fast neutron pulse in real time;The logging instrument of the application emits ultrashort fast neutron pulse and detects neutron yield in real time, combines to obtain neutron time spectrum and multi-dimensional information of gamma energy spectrum with accurate time stamp, carries out high-precision, anti-interference inversion to formation uranium content, and efficiently and accurately obtains formation information.

The invention provides a method and related equipment for monitoring soil water by separating neutron energy spectrums, and the method comprises the following steps: constructing a first-order inverse calculation formula according to bare tube neutron intensity, bare tube thermal neutron intensity, moderator neutron intensity, moderator epithermal neutron intensity and sample plot soil moisture of a plurality of sample plots; obtaining a decision coefficient of each first-order inversion formula; taking the first-order inversion formula with the maximum decision coefficient as a target formula; and obtaining a target factor of the to-be-detected area, determining the soil moisture of the to-be-detected area based on the target factor, and generating a monitoring report graph including the soil moisture of all the to-be-detected areas. The neutron energy spectrum is separated, the inverse calculations corresponding to different factors are generated, the coefficient is determined, the inverse calculation with the best accuracy is determined to be used for soil moisture estimation of the to-be-measured area, and on the basis that manual monitoring is reduced and the monitoring cost is reduced, the efficiency and accuracy of soil moisture estimation are guaranteed.

The application discloses a uranium-radium balance correction method, device, medium and equipment, relates to the uranium detection field of sandstone type uranium mines, and comprises the following steps: obtaining an industrial uranium mine hole, performing geophysical well logging on the industrial uranium mine hole, determining a mineralization section through quantitative gamma interpretation, performing geological logging and geophysical logging on a core, collecting and analyzing uranium-radium samples in the mineralization section, performing uranium fission prompt neutron logging on the mineralization section, determining a uranium mine section depth range according to the ratio of epithermal neutrons to thermal neutrons in the time spectrum of the uranium prompt neutron logging, determining a single sample section uranium-radium balance coefficient according to the uranium-radium sample analysis result of the mineralization section, determining a single project uranium-radium balance coefficient according to the single sample section uranium-radium balance coefficient, determining a uranium-radium balance coefficient zoning map according to the single project uranium-radium balance coefficient, correcting the quantitative gamma logging curve in the uranium mine section depth range of the uranium prompt neutron logging by using the coefficients in different uranium-radium balance zones, and obtaining the actual uranium mine section depth range, thickness and grade.

The invention discloses a method for removing natural radioactive isotope 138La in lanthanum oxide powder by using neutron irradiation. The method comprises the following steps: firstly, according to a neutron capture cross section curve of 138La in an ENDF / B-VIII.1 nuclear evaluation database, determining the optimal neutron energy as 3 eV; lanthanum oxide powder is packaged in a high-purity quartz ampoule which is placed in a neutron irradiation channel of a reactor. Most neutrons are moderated into epithermal neutrons with the energy of 3 eV by a heavy water layer of the reactor, and then the epithermal neutrons are emitted into lanthanum oxide powder. The neutron capture efficiency of the 138La in the irradiation process is obtained according to a Monte Carlo simulation method, the irradiation time required for completely converting the 138La into the 139La can be calculated by combining neutron flux data of a reactor, the mass of lanthanum oxide powder and the abundance ratio of the 138La, and the yield of the by-product 140Ce is evaluated. After irradiation is finished, standing and cooling are conducted for a period of time, the lanthanum oxide powder is placed in a low-background lead chamber, the residual radioactivity level of the lanthanum oxide powder is evaluated through a high-purity germanium detector, and the removal effect of 138La in the lanthanum oxide powder can be determined.

A cell mixture for the patient-specific treatment of solid tumors comprises carrier cells with a special loading. Immunocompetent autologous cells and / or genetically transfected cells are used, loaded with a combination of immunocompetent components and / or theranostic nanoparticles. The target tissue is derived from a tumor and includes malignant tumor cells and deactivated intratumoral cells, which are subsequently separated. Liposomes are loaded with a patient- and tumor-specific combination of immunocompetent components, namely at least one stable isotope with a high affinity for (epi-)thermal neutrons and / or a β- +The process involves the use of "decay" isotopes and / or a sensitizer to perform photodynamic therapy. Additionally, the cells are loaded with theranostic nanoparticles, which also allow for monitoring of the cells and charges involved. The carrier cells are gently loaded with the loaded liposomes via passive fusion. The loading rate of the carrier cells is significantly higher than with conventional methods, and at the same time, the carrier cells are highly specific to the individual tumor of the patient.

The invention discloses a neutron capture therapy device based on a DT tube, and the device comprises a beam shaping system, the interior of the beam shaping system is provided with a moderator, the moderator is composed of a mixture of aluminum fluoride and metal aluminum, and the preferable mass ratio is 40: 60. The beam shaping system further comprises a reflector arranged on the periphery of the moderator, a thermal neutron filter located at the downstream of the beam, a collimator at the emitting end and a shielding body used for restraining gamma rays, and an integrated structure for moderating, filtering and collimating 14 MeV fast neutrons generated by the DT tube is formed. The invention relates to the technical field of BNCT treatment equipment. Through cooperation of the composite moderator and structure optimization, the thermal neutron flux is remarkably reduced, the epithermal neutron flux is improved, the superthermal / thermal flux ratio of the emergent beam is remarkably improved, the fast neutron and gamma dose is effectively controlled, the IAEA recommended standard is met, and the method is suitable for miniaturization, popularization and application of compact clinical BNCT equipment.

The application discloses a beam shaping body for neutron capture therapy, which comprises a proton beam flow hole, a target body, a slowing-down body, a reflecting body surrounding the slowing-down body and the proton beam flow hole, a thermal neutron absorption layer adjacent to the slowing-down body, a gamma shielding layer adjacent to the thermal neutron absorption layer, and a collimating body arranged in the beam shaping body; the target body is arranged in the slowing-down body and at the end of the proton beam flow hole. The target body is arranged in the inside of the slowing-down body, and the target body is arranged to a depth of not less than 50 mm in the slowing-down body, so that the recoil neutrons are fully slowed down, and the super-thermal neutron flux of the exit is improved.

The invention discloses a method for measuring the uranium content of a multi-angle fractured sandstone uranium mine based on prompt neutron logging. The method comprises the following steps: firstly, establishing an instantaneous neutron logging model of the fractured sandstone uranium mine based on a Husdon fracture theory; then different fracture angles are set, and epithermal neutron counting and thermal neutron counting are obtained through simulation. According to the theory that the ratio of the epithermal neutrons to the thermal neutrons is in linear relation with the uranium content, numerical fitting is conducted on the curve of the ratio of the epithermal neutrons to the thermal neutrons and the uranium content through an exponential function, and the correction relation between the ratio of the epithermal neutrons to the thermal neutrons and the uranium content at different fracture angles is obtained. And finally substituting into an actual measurement result to obtain a more accurate uranium content. Through tests, the method for measuring the uranium content of the multi-angle fracture type sandstone uranium mine based on prompt neutron logging can effectively simulate prompt neutron logging response under fractures of different angles, and correct the linear relation between the ratio of epithermal neutrons to thermal neutrons and the uranium content, so that the more accurate uranium content is obtained.

The invention discloses a neutron beam generation system for neutron capture therapy. According to one embodiment of the present disclosure, there is provided a neutron beam generation system, comprising: an incident device for generating a proton beam; the RF linear accelerator is connected with the incident device so as to accelerate the proton beam; a beam line transmitting the proton beam accelerated by the RF linear accelerator; a target material which collides with the proton beam transmitted by the beam line and generates fast neutrons; and a deceleration means disposed on one side of the bunch and configured to decelerate the fast neutrons to epithermal neutrons.

The invention discloses a BNCT beam shaping body with an energy spectrum self-adjusting function, and particularly relates to the technical field of boron neutron capture therapy, and the BNCT beam shaping body comprises a neutron generation part, a beam shaping part, a beam shielding part and a beam leading-out part. According to the invention, the neutron generation part utilizes the low-energy incident proton beam to bombard the target material to generate the initial neutron source, and cooperates with the beam shaping part to carry out energy spectrum adjustment on the initial neutron source to obtain the epithermal neutron beam, and then the beam extraction part carries out collimation extraction on the neutron beam released by the beam shaping part. The influence of medium and photon rays on the surrounding environment is reduced through the beam shielding part; by adjusting the components, concentration and the like of the aqueous solution in the liquid moderator, accurate and rapid regulation and control of the neutron beam energy spectrum at the outlet of the beam shaping body can be realized in real time without changing the spatial arrangement of the beam shaping body, and the applicability and the flexibility of boron neutron capture therapy can be effectively improved; and effective formulation of a personalized treatment plan of subsequent boron neutron capture therapy is satisfied.

The invention relates to the technical field of medical device computer aided design crossing, in particular to a beam shaping assembly multi-strategy optimization design method for boron neutron capture therapy. According to the technical scheme, the method comprises the following steps: constructing a parameterized physical model of a boron neutron capture therapy beam shaping assembly based on a Monte Carlo program; in the wide decision space preliminary optimization stage, a plurality of decision variables including material types and geometric thicknesses of a plurality of moderated layers are defined, and a beam index at an outlet of a beam shaping assembly is set as a target function. Through a multi-stage strategy of wide decision space preliminary optimization, material frequency analysis and multi-objective function fine optimization, global automatic optimization of beam shaping assembly design is realized, the design efficiency is remarkably improved, the method enables beam indexes such as epithermal neutron flux, fast neutrons and gamma components to meet international standards at the same time, and the method is suitable for large-scale popularization and application. And the beam quality is improved, and the radiation dose and volume of the device are effectively controlled at the same time.

The present invention discloses a method for automatically extracting inelastic gamma rays from pulsed neutron logging, belonging to the technical field of oilfield logging. The method comprises the following steps: a. performing pulsed neutron logging to obtain a gamma ray energy spectrum during a time gate; b. deducting a certain proportion of the gamma ray energy spectrum during the early capture time gate and the gamma ray energy spectrum during the late capture time gate from the gamma ray energy spectrum during the pulsed time gate, and obtaining the optimal coefficients under different porosities through fitting; c. establishing a relationship between the coefficients and the count rate measured by the detector. As long as the detector count rate is obtained, the inelastic spectrum count rate can be calculated. The present invention takes epithermal neutron capture into account, i.e., the capture spectrum is considered to be epithermal neutron capture plus thermal neutron capture, thereby more accurately extracting net inelastic gamma rays, laying a good foundation for implementing high-precision controlled source density logging methods.