190 results about "Gamma energy" patented technology

A method and apparatus for discriminating the types of radiation interacting with an integrated radiation detector having of a pulse-mode operating photosensor which is optically coupled to a gamma-ray scintillator sensor and a neutron scintillator sensor and uses an analog to digital converter (ADC) and a charge to digital converter (QDC) to determine scintillation decay times and classify radiation interactions by radiation type. The pulse processing provides for, among other things, faithful representation of the true energy spectrum of the gamma radiation field and allows for radioisotope identification by searching for the presence of characteristic energy lines in the gamma energy spectrum. The pulse shape discrimination method ensures that the high sensitivity and resolution of the isotope identification function is not affected during operation in mixed neutron-gamma fields.

The invention relates to a multi-parameter logging method while drilling based on a controllable neutron source, which includes the steps of utilizing a multi-detector measuring system consisting of the D-T controllable neutron source, two thermal neutrons and two gamma detectors, sufficiently utilizing fast neutrons transmitted by the controllable neutron source to militate with atomic nucleuses of formation elements by means of special pulse and measuring timing sequence design, recording gamma energy spectrums, gamma time spectrums and thermal neutron time spectrums at different positions, and performing simultaneous measurement of multiple parameters such as formation density, formation porosity, formation fluid saturation, formation element content and the like with a nuclear logging instrument in a drilling process by means of different spectral resolution and data processing, so that valuation on formation lithology, formation porosity and formation fluid saturation while drilling are realized, the same parameter of the formation porosity and the formation fluid saturation can be measured by various methods, logging interpretation ambiguity is decreased, and accuracy and reliability of logging data interpretation are enhanced.

An integrated radiation detector having a pulse-mode operating photosensor optically coupled to a gamma sensing element and a neutron sensing element is disclosed. The detector includes pulse shape and processing electronics package that uses an analog to digital converter (ADC) and a charge to digital converter (QDC) to determine scintillation decay times and classify radiation interactions by radiation type. The pulse shape and processing electronics package determines a maximum gamma energy from the spectrum associated with gamma rays detected by the gamma sensing element to adaptively select a gamma threshold for the neutron sensing element. A light pulse attributed to the neutron sensing element is a valid neutron event when the amplitude of the light pulse is above the gamma threshold.

The invention relates to an NaI (TI) scintillation detector gamma energy spectrum high-resolution inversion analysis process and method based on a gauss response matrix. The analysis process comprises the steps of spectral line pretreatment, peak searching and peak boundary treatment, resolution ratio ruling, background subtraction, gauss response matrix generation and inversion analysis. According to the feature of an NaI (TI) scintillation detector and the physical property of the spectrum forming process, response, in the detector, of different energy gamma photons corresponds to different full widths at half maximum of a photo peak, and the photo peak is approximate to a gauss function in shape. The parameters of the full widths at half maximum of a spectral line are extracted, the background is subtracted from the full widths at half maximum adaptively, the universal gauss response matrix between a radioactive source and a gamma spectrum is constructed, and finally the response matrix is used for inversion analysis of other gamma instrument spectrums measured by the NaI (TI) scintillation detector. The result analyzed through the method is an energy point corresponding to the measured spectral line under the response matrix or is approximate to the solution of a physical spectral line in theory, and the ability of the method to analyze the spectral line is obviously improved.

The invention provides a gamma nuclide fast identification method in a complex radiation field, comprising the following steps: measuring a radiation field to get a gamma energy spectrum; deducting a comprehensive background from the gamma energy spectrum and reducing the noise of the gamma energy spectrum to get a net energy spectrum; determining potential nuclides according to the peak positions in the net energy spectrum; calculating the total net peak area of each potential nuclide; standardizing the total net peak area of each potential nuclide to get the standardized total net peak area of the potential nuclide; deducting a Compton scattering background from the standardized total net peak area of each potential nuclide to get the pure peak area value of each potential nuclide; calculating the total probability value and the probability standard threshold of each potential nuclide in the radiation field; and calculating the existence probability of each potential nuclide. According to the invention, multiple times of background deduction calculation and standardization are performed on the measured energy spectrum data, and a nuclide can be identified and the existence probability of the nuclide can be calculated quickly based on the total probability value calculated based on the probability statistics principle and the standard threshold calculated by a standard source.

The invention discloses a digital logarithm gamma energy spectrometer, which comprises a NaI crystal, a photomultiplier, a high-voltage power supply module, a preamplifier, a logarithmic amplifier, a gain-programmed amplifier, an anti-aliasing active filter, a high-speed analog-digital converter (ADC) and a CPLD programmable logic device, wherein the logarithmic amplifier performs logarithmic operation on received nuclear pulse signals to acquire a high energy section spectral line and a low energy section spectral line; the high-speed analog-digital converter (ADC) performs analog-digital conversion on filtered signals; and the CPLD programmable logic device realizes pulse amplitude analysis, baseline restoration and filtering de-noising to digital signals, and obtains information on corresponding nuclear pulse peak values. The logarithmic amplifier performs logarithmic compression on the nuclear pulse signals to ensure the resolution of the high energy spectral line and the low energy spectral line; and the high-speed analog-digital converter and the CPLD programmable logic device are adopted to realize a digital energy spectrometer and ensure the high counting pass rate and the energy resolution of the energy spectrometer.

The invention provides a method for identifying gamma energy spectrum nuclides, which comprises the following steps of: (a) acquiring a gamma energy spectrum; (b) seeking for a peak in the energy spectrum and calculating the area of the peak; (c) obtaining candidate nuclides, which are possibly present, by matching the found peak with a spectral line of nuclides in a nuclide library; (d) calculating the occurrence possibility of each candidate nuclide by using a Bayesian network model; and (e) eliminating the situation in which mutual interference exists between the candidate nuclides due to the matching of the same peak, and updating the occurrence possibility of each candidate nuclide to obtain a final confidence coefficient.

The invention relates to a LaBr3(Ce) crystal-based multi-channel gamma energy spectrum logging instrument. The instrument comprises a probe part, an operating platform, a cable and a winch, wherein the probe part comprises a LaBr3(Ce) crystal gamma ray detector formed by combining LaBr3(Ce) and a photomultiplier, a spectroscope amplifier, a peak holding circuit, a pulse amplitude analyzer and a high and low voltage power supply; the operating platform comprises a power supply converter and a computer; and the spectroscope amplifier receives a pulse signal from the detector, the pulse signal is input into the pulse amplitude analyzer through the peak holding circuit after passing through the spectroscope amplifier, and digital information output by the pulse amplitude analyzer is connected with a 485 communication interface of the computer through a 485 communication interface of the probe, and the cable. The logging instrument can directly measure the characteristic energy spectra of various radionuclides such as a uranium family, a thorium family, potassium and the like in nuclear resource logging, and has the characteristics of high energy resolution, measuring efficiency and stability, and the like.

The invention discloses a nuclide recognition device in a high-level radioactive environment. The device consists of a digitalized gamma energy spectrum acquisition system, a monitoring host, mobile equipment and a wireless network, wherein the digitalized gamma energy spectrum acquisition system and the mobile equipment are controlled by the monitoring host through the wireless network. The nuclide recognition device has the advantages that: in the high-level radioactive environment, full-automatic nuclide detection is realized; the potential health harm suffered by workers during manual detection in the high-level radioactive environment is avoided and the shortcoming of the manual detection is overcome; meanwhile, the problem that information acquisition is finite during conventional nuclide detection is solved.

The invention discloses a temperature drift self-correction method of a sea radioactivity measurement sensor, and a sensor. A temperature-sensitive element is additionally arranged on the sensor, the temperature of the sensor is detected through the temperature-sensitive element, the amplification gain of the sensor is automatically adjusted according to temperature change of the sensor, and amplitude of pulse voltages generated by the sensor is adjusted to the amplitude of pulse voltages generated when the sensor measures the same radionuclide at a reference temperature, such that peak drift of gamma energy spectrum data generated by the sensor can be automatically corrected and a more accurate detection result can be obtained. By using the sensor provided by the invention, the activity of such radionuclide as seawater, seabed sediment, marine organisms and the like in a sea environment can be automatically and continuously monitored for long time and a stable reliable monitoring result can also be obtained; and the method and the sensor can also be suitable for various sea automatic monitoring platforms and can be promoted and applied to the radioactivity monitoring work process of other water body environments.

The invention relates to a three-energy coal ash content online monitoring device which comprises a low-energy gamma source Am241, an intermediate-energy gamma source Cs137, and a lanthanum bromide detector for receiving the low-energy and intermediate-energy gamma rays, wherein gamma photons emitted by the low-energy gamma source Am241 and the intermediate-energy gamma source Cs137 irradiates the coal sample in a sample container; the output terminal of the lanthanum bromide detector is connected with the input terminal of a multi-channel data analysis spectrometer; the collected gamma energy spectrum information and the characteristic X-ray spectrum information are transmitted to a data processing and spectrum unscrambling system; and the data processing and spectrum unscrambling system is used for processing the data. The three-energy coal ash content online monitoring device can be used for coal sampling and automatic rapid detection of as-received coal vehicles without bypass belts, and can be mounted and detected only by slightly changing the structure of the rear end of the sample container.

The rare earth metal Lutetium in compound form is used in check sources of various shapes and sizes to calibrate and tune radiation detection devices. Radioactive Lutetium-176, a naturally occurring (non man-made) isotope forming part of the Lutetium compound, produces gamma energies of approximately 90, 200, and 300 kilo-electron Volts which are used in the calibration. Such gamma energies are close to the predominant spectral lines of special nuclear materials such as U-235 and Pu-239, which is to be monitored by radiation detection devices. Lutetium in a radioactive calibration source (which is either integrated into the radiation detection device or positioned close to it during calibration) provides benefits including that no reactor or accelerator is required during production or use, for the creation of man-made radioactivity, no dangerous radiation exposure occurs and (because of the long half-life of Lu- 176) the radioactive calibration source essentially never needs to be replaced. Moreover, the handling of such a source is much less restrictive and costly than that of a conventional man-made radioactive isotope.

The invention relates to a method and a device for identifying a radionuclide Sr-89 and analyzing a nuclear purity. The method comprises the following steps of: (1), calibrating the activity of a sample and measuring the gamma radioactive source detection efficiency of a NaI gamma energy spectrometer; (3), calculating to obtain the emissivity of a gamma ray; (4), acquiring that the energy of the gamma ray is 909 Kev by the position of a gamma peak, obtaining that an energy specific value is approximately equal to 0.01% by the emissivity of the gamma ray and the activity of the sample, and determining that a nuclide is the Sr-89; and calculating to acquire the purity. The device comprises a lead chamber, a NaI crystal and photomultiplier, a lead tank, a plastic container, a penicillin bottle and a plastic cup. By using the method and the device, the strontium-89 nuclide and the nuclear purity are quickly and highly sensitively identified; by using the method and the device, the difficulty of a technical requirement on an operator is low; compared with the utilization of scintillating liquid, the amount of a radioactive waste can be reduced to improve the environment; meanwhile, the investment through which an enterprise needs to establish new equipment and an instrument is reduced; and the method and the device have a favorable application prospect.

The invention discloses a low background gamma energy dispersive spectrometer for ocean radioactive measurement. The low background gamma energy dispersive spectrometer for the ocean radioactive measurement comprises a crystal array detecting module composed of six NaI (T1) crystal sensors, a signal processing module and an upper computer. The six NaI (T1) crystal sensors are evenly divided into three groups. The two NaI (T1) crystal sensors in each group are arranged oppositely. Crystal end faces of the six NaI (T1) crystal sensors are adjacent so that a zone used for placing a sample box is defined. Six ways of output detected signals are detected by the six NaI (T1) crystal sensors, transmitted to the signal processing module, processed to energy spectrum signals through the signal processing module and transmitted to the upper computer. The energy dispersive spectrometer can be used for conducting rapid detection on radionuclide content in a marine environment, suitable for laboratory detection and field monitoring of vehicle mounting and ship mounting and capable of being popularized and used in detection works of other samples with low radioactivity except for the marine environment.

The invention discloses the concrete steps of analysing method for coal element, which is based on the GenBank least square method and adopting a scintillation detector as the recording device and adopts the spectrum based least square method to make the spectrum analysis so as to avoid errors caused by current spectrum analysis technology and the structure of the on-line detecting device meet the necessity of the method. It adopts all of the information of gamma energy spectrum so as to avoid the error caused by spectrum stripping technology and enhance the sensitivity of detection, the reliability of measurement and the stability of the device.

The invention discloses a method for measuring neutron, gamma energy spectrum and dosage in a nuclear power station. The method comprises the following steps: 1 ) the neutron and gamma rays are inputinto a neutron detection system to output a signal A, and the gamma rays are input into a gamma detection system to output a signal B; 2) the signal A and the signal B are input into a digital signalprocessing circuit to be subjected to operation processing to obtain the neutron, gamma energy spectrum and dosage, wherein the digital signal processing circuit takes a field-programmable gate arraychip as a core chip. Compared with the prior art, the method for measuring neutron, gamma energy spectrum and dosage in the nuclear power station disclosed by the invention has the advantages that thesimulations measurement of the neutron, gamma energy spectrum and dosage can be realized based on the field-programmable gate array technology. In addition, the invention further discloses a system for measuring the neutron, gamma energy spectrum and dosage in nuclear power station.

The invention discloses an aviation gamma energy disperse spectroscopy spectrum stabilization method based on the energy spectrum reconstitution technology. The aviation gamma energy disperse spectroscopy spectrum stabilization method is characterized in that a linear relation between the change rate of characteristic peak position track addresses, measured by a NaI gamma energy disperse spectroscopy, of energy incidence gamma rays at different temperatures to the characteristic peak position track address of corresponding energy incidence gamma rays at the standard temperature and the temperatures is obtained in an experiment chamber so as to serve as a standard reference system, an energy nonlinearity rule actually measured at the standard temperature is used in a combined mode, and impulse amplitudes generated by the different energy incidence gamma rays at the different temperatures are corrected into impulse amplitudes corresponding to the specific energy linearity at the standard temperature; the corrected impulse amplitudes within a set measurement time interval are counted in a classified mode according to the specific impulse amplitude interval, and reconstitution energy spectra of the energy linearity are obtained. The problems that the NaI gamma energy disperse spectroscopy measurement energy scopes are not coincident due to spectrum shifting, a single reference point cannot conduct spectrum stabilization within a full-measurement energy scope due to energy nonlinearity, and delaying of the spectrum stabilization operation is caused are solved.

The invention relates to a digital neutron spectrometer, which comprises a detector unit, a mechanical control unit, a digital acquisition unit and a discrimination unit, wherein the detector unit is used for detecting neutron information of a radiation field to be detected; the mechanical control unit is used for controlling rotation and lifting of the detector unit; the digital acquisition unit is used for converting analog signals generated by the detector unit into digital signals; and the discrimination unit is used for analyzing the shape of pulses of the detector unit, and judging whether the pulses belong to neutron pulse signals or Gamma-ray pulse signals in real time. The neutron spectrometer provided by the invention is wide in neutron energy measurement range, can effectively determine an effective central position of detector measurement, reduce mutual scattering influences of detectors, has a good neutron and photon real-time discrimination ability, and respectively gives neutron and Gamma energy spectrum information in a neutron-Gamma mixed filed in real time.