8 results about "Inelastic scattering" patented technology

To provide a neutron detection device capable of detecting high-energy neutrons with high sensitivity, and a highly sensitive nuclear material detection device using the same. [Solution] This nuclear material detection device 1 detects nuclear material by the TENA method. It uses a neutron source 10 that emits primary neutrons N1 toward a sample 100, and a neutron detector 20 that detects neutrons (primary neutrons N1 and secondary neutrons N2) emitted from the sample 100. It also uses an analysis unit 30 that recognizes high-energy neutrons by analyzing the detection results of the neutron detector 20. When the energy of the neutrons is high, 16 O and 12 Electrons with particularly high energy are generated by inelastic scattering of neutrons by C. In the case where a neutron with particularly high energy is incident, the neutron detection device 40 recognizes the high-energy neutron by utilizing the fact that Cherenkov light caused by such high-energy electrons is detected by a photodetector.

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 present invention discloses an element distribution imaging device and method based on a rotary modulation collimator. The measuring device comprises a neutron generator, a rotary modulation collimator, a gamma ray detector and a data acquisition and processing system. The rotary modulation collimator comprises two encoding plates, a cylinder, a synchronous belt and a motor. The sample to be tested is placed in a neutron field between the neutron generator and the rotary modulation collimator. The elements to be tested in the sample to be tested react with the neutrons in the neutron field and emit characteristic gamma rays of different energies through capture reaction and inelastic scattering. The characteristic gamma rays change in flux after passing through the encoding plate. The gamma ray detector measures the characteristic gamma rays after the flux changes. The gamma ray detector is connected to the data acquisition and processing system. The gamma ray detector can send the measured characteristic gamma ray data to the data acquisition and processing system. The present invention has the advantages of high detection accuracy, high detection efficiency and short measurement time.

A method for the spatially-resolved probing of bio logical tissue (102) comprises the steps of emitting, by means of at least one light source (106), a series of light pulses into the tissue and of measuring, by means of a plurality of light detectors (108), a plurality of time-resolved responses to the light pulses scattered from the tissue. The measurement is carried out with a temporal resolution better than 20 ps. A plurality of first responses is in response to light pulses at a first illumination band and is measured at a plurality of first detection bands. The first detection bands differ from each other and from the first illumination band in order to detect inelastic scattering. A plurality of second responses is in response to light pulses at a second illumination band and is measured at a second detection band. The second detection band overlaps with the second illumination band in order to detect elastic scatting. Time of flight analysis of both responses allows to e.g. use elastic scattering for locating structures (S1, S2, S3) in the tissue (102) and for assigning them to the inelastic scattering data.

The invention relates to the technical field of secondary electron emission, in particular to a secondary electron emission analysis method and system under the synergistic effect of a carbon thin film and a rectangular groove, and the method comprises the following steps: constructing a secondary electron emission numerical simulation model under the synergistic effect of an amorphous carbon thin film and the rectangular groove; after an electron enters the amorphous carbon film, the scattering type is determined according to a first condition, if the scattering type is satisfied, elastic scattering is simulated according to a Mott scattering theory, otherwise, inelastic scattering is calculated according to a Penn dielectric function model. And the electrons move to a material interface and are emitted if the interface barrier overcoming condition is met, secondary electron emission is recorded, and simulation is terminated. According to the model, multiple factors are integrated, the secondary electron emission process is accurately simulated, the synergistic effect is considered, so that the result is more practical, scattering simulation is fine and targeted, electron emission and simulation termination are reasonably judged, important assistance is provided for material research and electronic device design, material performance can be optimized, and device performance can be predicted.

The application discloses a formation density measurement method, a storage medium and equipment, and relates to the field of well logging technology. The method comprises the following steps: establishing a neutron logging model of formation density for representing the relationship between the formation density and the non-elastic gamma count ratio and the thermal neutron count ratio; and substituting the non-elastic scattering gamma ray count ratio, the thermal neutron count ratio and a plurality of calibration coefficients of a target formation of a well to be measured into the neutron logging model of formation density to obtain the formation density of the target formation of the well to be measured. According to the method, the final formation density can be obtained by using the thermal neutron and the non-elastic gamma count. The method has the characteristics of small influence of formation lithology, high measurement efficiency and simple design of related instruments.

Methods and systems for determining a carbon-to-oxygen (C / O) ratio within a formation are described. The methods and systems use a pulsed neutron tool conveyed within a borehole in the formation to measure gamma rays induced by inelastic scattering events between pulsed neutrons and elements within the formation. The resulting inelastic scattering spectra are treated to remove baseline counts arising from interactions occurring within scintillation materials of the detector and are then deconvolved using elemental standard spectra that are similarly detrended to remove baseline contributions.

The present invention discloses a waterflood identification method based on the dual physical processes of pulsed neutron moderation and diffusion, belonging to the technical fields of geophysical logging and oilfield development. A pulsed neutron detection system composed of a D-T controllable neutron tube source and a dual-spacing thermal neutron detector is adopted to extract the thermal neutron count ratio and the macroscopic capture cross-section to quickly realize the evaluation of reservoir waterflooding. This method is based on the interaction processes such as inelastic scattering, elastic scattering, and radiative capture that occur between neutrons and the atomic nuclei of formation elements. By utilizing the characteristics that the moderation process of neutrons is closely related to the hydrogen content in the formation, while the diffusion process is mainly affected by the capture ability of the formation, new parameters are constructed by integrating the two physical processes, significantly improving the response degree to reservoir waterflooding. This method has a high interpretation coincidence rate, can eliminate the influence of formation water salinity and porosity on the evaluation of waterflooded layers, and can provide a theoretical basis and technical support for quickly and accurately identifying the waterflooding situation of reservoir by pulsed neutron lifetime logging.