9 results about "Epithermal neutron" patented technology

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.

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 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.

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 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.

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.