6 results about "Gamma detection" patented technology

This invention discloses a neutron analysis physics testing system and method, belonging to the field of nuclear physics testing technology. The system includes: a high-speed synchronous pulse generator for generating pulse signals with multiple modulation sequences; an ultrashort pulse neutron generator for emitting short pulse neutron rays with specified parameters onto a sample; a neutron detector for acquiring secondary neutron signals; a gamma detector for acquiring characteristic gamma signals generated by neutron-excited probes of the sample; a safety control module for controlling the operating state of the ultrashort pulse neutron generator; and a data processing device for real-time collection and summarization of neutron signals and characteristic gamma signals based on the timing of the pulse signals with multiple modulation sequences. This system reduces time window drift and measurement errors, and activates the ultrashort pulse neutron generator only when a gate signal allows, improving the accuracy, safety, and stability of geological physics parameter measurements.

The application discloses a positron annihilation lifetime measurement device and method for thin film sample characterization, which is composed of a positron emitter, a positron detector and a gamma detector; a sample is placed between the positron emitter and the positron detector. The positron emitter contains a radioactive source and is responsible for detecting the positrons entering the sample, and the positron detector is responsible for detecting the positrons penetrating the sample. The gamma detector is responsible for detecting the 0.511 MeV gamma photons generated after the positrons are annihilated. The application can break through the limitation of measuring the sample thickness, is suitable for all types of positron radioactive sources, and sufficiently widens the experimental conditions; meanwhile, the non-contact measurement function can expand the application of the positron annihilation lifetime measurement method in the measurement of special samples and special environments.

The anti-seismic natural gamma-ray logging instrument detection device comprises a gamma-ray detector damping body, the two ends of the gamma-ray detector damping body are fixedly connected with centralizing end plates correspondingly, and the centers of the gamma-ray detector damping body and the centralizing end plates are jointly provided with a threading pipe in a penetrating mode in the length direction; two sets of fixing units are arranged in the gamma detector damping body in the length direction at intervals, each set of fixing units comprises four cavity type fixing bins, and the four fixing bins are evenly distributed in the circumferential direction of the threading pipe. The four fixing bins of one set of fixing units and the four fixing bins of the other set of fixing units are arranged in a one-to-one staggered mode in the circumferential direction of the threading pipe, and each fixing bin is filled with a gamma detector. The invention further discloses an assembling method of the anti-seismic natural gamma-ray logging instrument detection device. The problem that in the prior art, due to the fact that a natural gamma-ray logging instrument is poor in anti-seismic performance, a gamma-ray detector is damaged and cannot work is solved.

The application relates to the technical field of gamma spectrum analysis, and particularly provides a gamma detector activation analysis method and a PGNAA detection system, which aims to solve the technical problem that the gamma rays obtained by detecting the existing gamma detector include rays generated by the activation and decay of crystals in a neutron field, thereby causing the component detection result of a to-be-detected sample to be inaccurate. For this purpose, the gamma detector activation analysis method comprises the following steps: irradiating a to-be-detected sample by using a neutron source; repeatedly collecting multiple groups of gamma spectra of the to-be-detected sample by using a gamma detector; constructing a spectrum signal matrix based on the gamma spectra of the to-be-detected sample, wherein the spectrum signal matrix is a mixed signal composed of prompt gamma rays generated by the neutron activation of the to-be-detected sample, environmental background gamma rays and interference signals generated by the activation of crystals in the gamma detector; and obtaining effective prompt gamma rays based on the spectrum signal matrix. The self-interference influence of the detector is effectively reduced, and the evaluation precision of the target element content of the to-be-detected sample is improved.

The present application relates to the technical field of prompt gamma neutron activation analysis and non-destructive testing of industrial materials, and particularly relates to a multi-element gamma spectrum quantitative inversion algorithm based on polynomial forward and Newton iteration. The technical scheme comprises the following steps: obtaining a gamma spectrum obtained by neutron activation measurement, and extracting a plurality of gamma detection characteristic values corresponding to a plurality of elements; based on the plurality of gamma detection characteristic values and the true mass fraction of the corresponding sample elements, a polynomial forward model is established, and based on the gamma detection characteristic values and the true mass fraction of the elements, a direct polynomial inverse model is established. The present application effectively improves the accuracy of multi-element gamma spectrum quantitative inversion, enhances the robustness and convergence stability of the algorithm under complex materials, improves the generalization ability of the model to different matrix environments, and has good engineering practicability.

This invention discloses a plutonium-containing material measuring device, relating to the technical field of radioactive element measuring devices. The device includes a measuring chamber, a lower cover assembly, and an automatic feeding structure. A gamma detector is installed above the measuring chamber, and a neutron detector is installed inside. The automatic feeding structure includes a horizontal transmission mechanism and a synchronous lifting mechanism. The synchronous lifting mechanism is a symmetrical structure driven by a single power source. The lower cover assembly, which carries the material to be measured, is placed on the horizontal transmission mechanism and can be conveyed horizontally to the lifting position. The synchronous lifting mechanism then conveys the lower cover assembly along with the material to be measured vertically into the upper measuring chamber, and the lower cover assembly seals the bottom of the measuring chamber, thus forming a closed measuring space. The device provided by this invention can simultaneously perform neutron and gamma measurements on materials, reducing measurement time, minimizing transport time, reducing radiation hazards to personnel, reducing equipment size, and increasing measurement accuracy.