585 results about "Scintillation" patented technology

The invention provides a laser radar and gamma camera integrated detection system based on a shared SiPM array, and belongs to the field of detector equipment. The system comprises a laser emission module, a gamma camera, an optical module, an SiPM array detection module, a signal processing module and a control module. Wherein the optical module controls high-frequency pulse laser of the laser emission module to scan a target scene, respectively guides a reflected laser beam and a scintillation light signal emitted by the gamma camera to the SIPM array detection module for photoelectric conversion to generate an electric signal, and performs gain and time gate adjustment according to a sensor working mode to obtain a first electric signal; the signal processing module receives the first electric signal and carries out laser radar ranging calculation and gamma camera imaging processing to obtain three-dimensional point cloud data and a radioactivity distribution image of the target scene. According to the invention, efficient fusion of functions of the laser radar and the gamma camera is realized, the size and weight of the system are greatly reduced, and the manufacturing and maintenance cost is also reduced.

The invention discloses a micron-resolution boron nitride neutron scintillation screen and a preparation method thereof, and the preparation method comprises the following steps: taking an inch-level sapphire single crystal as a substrate, and selecting an aluminum polar surface as a growth surface; fixing the substrate by using a graphite clamp, putting the substrate and the chemical vapor deposition furnace into a chemical vapor deposition furnace, vacuumizing, and heating the furnace body to a reaction temperature by using a graphite heater; then raw material gas and carrier gas N2 are introduced into the furnace, meanwhile, the graphite clamp and the graphite heater are decomposed at high temperature so as to provide a proper amount of carbon source, and the gas is mixed and reacts to deposit a crystalline boron nitride film on the substrate; and soaking with alcohol to separate the boron nitride film from the substrate, cutting, and fixing on an aluminum plate to prepare the neutron scintillation screen. The boron nitride film is compact and transparent, shows a strong blue light emission characteristic due to carbon defects, and can be used as a micron-resolution neutron scintillation screen. The micron-resolution boron nitride neutron scintillation screen is successfully realized, and the potential of the micron-resolution boron nitride neutron scintillation screen in the aspect of high-resolution neutron imaging is proved.

The invention belongs to the technical field of nuclear radiation measurement, and relates to a liquid flash TDCR multi-nuclide beta spectrum analysis method and system based on artificial intelligence. The method comprises the following steps: constructing a numerical model of a liquid flash detector spectrometer by using a Monte Carlo technology to simulate the energy spectrum response of a single nuclide under different quenching conditions; constructing a training database by adopting a parameterized data synthesis algorithm; constructing a multi-task mixed spectrum analysis neural network model; carrying out model training by utilizing the constructed database; and inputting an actual measurement spectrogram, and outputting the multi-nuclide absolute activity, the detector efficiency and the decomposition energy spectrum contribution curve in real time by using the trained neural network model. According to the method, differential distribution characteristics and quenching response curve characteristics of the beta continuous energy spectrum are creatively fused, a neural network architecture with physical mechanism constraints is constructed, and liquid flash TDCR multi-nuclide energy spectrum characteristic decoupling and accurate activity solving are achieved under the unknown quenching condition.

The invention relates to the technical field of nuclear radiation imaging, in particular to a radiation array detector, a back scattering imaging system and a back scattering imaging method. The radiation array detector comprises an X-ray photon absorption structure which comprises high-strip-shaped scintillators and low-strip-shaped scintillators which are alternately arranged, the high-strip-shaped scintillators are used for detecting back scattering X-ray photons incident at all angles, the low-strip-shaped scintillators are used for accurately determining the incident direction of the X-ray photons through the collimation effect, and the high-strip-shaped scintillators and the low-strip-shaped scintillators are used for detecting the incident direction of the back scattering X-ray photons; after X-rays enter the photon absorption structure, the high-strip-shaped scintillators and / or the low-strip-shaped scintillators receiving X-ray photons generate scintillation photons. The silicon photomultiplier array is connected with the high strip-shaped scintillator and the low strip-shaped scintillator through a light guide and is used for converting scintillation photons into photoelectric signals; and the position and energy information coding circuit is used for carrying out position and energy information coding on the photoelectric signals generated by the silicon photomultiplier array. According to the invention, the detection efficiency and the direction identification capability of the back scattering X-ray can be effectively improved.

The invention provides an ionospheric scintillation phenomenon monitoring method and system, terminal equipment and a storage medium, and the method comprises the steps: controlling a receiver end to carry out the data processing of a received satellite signal, and generating a dual-frequency carrier phase observation value of the satellite signal; calculating the total electron content of an ionized layer on an inclined path in each observation epoch based on the double-frequency carrier phase observation value; acquiring the total electron content of the ionized layer on an inclined path in each observation epoch in the current detection period, generating a change rate index of the total electron content of the ionized layer in the current detection period based on the total electron content of the ionized layer, and when the change rate index of the total electron content of the ionized layer is greater than a preset change rate index, detecting the total electron content of the ionized layer in the current detection period. And judging that the ionospheric scintillation phenomenon occurs in the current detection period. The reliability and economical efficiency of ionospheric scintillation monitoring can be improved.

The invention provides a preparation method of a reconfigurable glass scintillation screen and application of the reconfigurable glass scintillation screen in X-ray co-formation imaging, and belongs to the technical field of X-ray imaging, and the preparation method specifically comprises the following steps: raw material pre-synthesis, high-temperature melting, glass scintillation screen forming and reconstruction processing. The problems that a commercial scintillator in a flat plate type X-ray detector is high in processing difficulty, the shape of the commercial scintillator is not plastic, the commercial scintillator cannot be conformal with a measured object with an irregular shape and the like are effectively solved, and meanwhile, the problems of light scattering and transmittance reduction in a conventional polymer-doped flexible scintillation screen are solved. The shape of the glass scintillation screen can give full play to the reconfigurable characteristic of the glass scintillation screen, the glass scintillation screen is processed according to the shape of a measured object, conformal X-ray imaging is further completed under the condition that the shape of the object changes continuously, the problem of imaging distortion caused by non-conformal imaging is effectively solved, and the imaging resolution is high.

The invention provides a muon detector for measuring soil moisture, and belongs to the technical field of testing by utilizing wave or particle radiation. The muon detector comprises a tubular scintillator which is used for detecting muons in cosmic rays and emitting scintillation light, and at least two outer optical fibers which are equal in screw pitch and used for collecting and transmitting the scintillation light are spirally wound on the periphery of the tubular scintillator. At least two inner optical fibers which are equal in screw pitch and used for collecting and transmitting scintillation light are spirally arranged on the inner circumference of the tubular scintillator, and the rotation direction of each inner optical fiber is opposite to that of each outer optical fiber, so that the tubular scintillator is divided into a plurality of latticed detection units in the internal and external directions. Compared with the prior art, the latticed detection unit is smaller, the existing scintillation light signal can only be acquired by the outer optical fiber, the scintillation light signal can also be acquired by the inner optical fiber, the optical fiber closer to the optical fiber can be acquired by the optical fiber, and the inner optical fiber and the outer optical fiber form an acquisition network, so that the detection precision is higher.

The invention discloses a hybrid neutron gamma detector array and a signal processing method, and relates to the technical field of nuclear physical detection.During detection, eight EJ200 scintillators arranged in an array are used for energy deposition of gamma rays and fast neutrons and generating photons, and meanwhile three EJ426 thermal neutron scintillation screens are used for capturing thermal neutrons and generating photons; the response of gamma rays, fast neutrons and thermal neutrons is realized at the same time, and the detection precision is greatly improved. Meanwhile, if the three EJ426 thermal neutron scintillation screens are alternately stacked front and back, the total reflection of the EJ200 scintillators and the semi-light-proof performance of the EJ426 thermal neutron scintillation screens are utilized to block photon propagation in the X direction and only enable photons to be propagated in the Y direction and the Z direction, and each EJ200 scintillator corresponds to a four-channel photon collection structure to perform high-efficiency collection of the photons, so that the high-efficiency collection of the photons is realized. Therefore, high-precision detection and high-efficiency photon collection are realized, and support is provided for subsequent intense radiation field monitoring or high-precision positioning.

Method of measuring ionosphere scintillation phase index Sigma-Phi, the method including, for each of N satellites being tracked, calculating a phase prediction at an i-th sample; for each of the N satellites, calculating an individual loop discriminator signal based on the phase prediction; rejecting the i-th samples of some of the N satellites, where K non-rejected satellites remain; calculating common loop discriminator signal based on the individual loop discriminator signals of non-rejected K satellites; calculating a phase estimate and a Doppler frequency estimate at the i-th sample for each of the N satellites based on individual loop discriminator signal; calculating test statistic based on the phase estimate at the i-th sample and an observed phase for each of the N satellites; calculating index Sigma-Phi as standard deviation estimation of the test statistic for each of the N satellites; and outputting the index Sigma-Phi for each of the N satellites.

The invention discloses a data management method and device, electronic equipment and a storage medium, and belongs to the technical field of electronic equipment. The method comprises the following steps: carrying out fast Fourier transform (FFT) calculation on first data stored in an annular buffer area of the scintillation sensor, and obtaining a first calculation duration for carrying out FFT calculation on the first data; predicting a second prediction duration of the next FFT calculation based on a first prediction duration of the previous FFT calculation and the first calculation duration; determining a target window value based on the second prediction duration and an FFT calculation reference duration; and according to the target window value, storing second data collected by the scintillation sensor into the annular buffer area.

The embodiment of the invention particularly relates to a dosage monitoring device based on a scintillation fiber array and a beam control device. In the dose monitoring device, when a beam passes through a two-dimensional scintillation optical fiber array detector, a plurality of first scintillation optical fibers arranged in parallel in a first scintillation optical fiber layer and a plurality of second scintillation optical fibers arranged in parallel in a second scintillation optical fiber layer are excited to emit scintillation fluorescence, and the scintillation fluorescence is transmitted along the optical fibers and received by a photoelectric detection unit; and the photocurrent signal is further converted into a voltage pulse signal by the current-voltage conversion unit, and the output dose information and the radiation field dose distribution information of the electron accelerator can be further obtained according to the voltage pulse signal.

Several new techniques for designing nanophotonic scintillators which lead to optimal performance and novel functionalities. Important design concepts include the use of absorbing structures inspired by solar cells, angularly-selective structures, and metasurfaces. Scintillators based on conventionally overlooked materials (such as GaAs or GaN) are also disclosed, which are designed to reach efficiencies comparable or superior to state-of-the-art conventional scintillators (such as YAG:Ce and LYSO). Such scintillators provide important enhancement of scintillation yield arising from incorporation of nanophotonic patterns. Additionally, nanophotonic scintillators designed in conjunction with image post processing algorithms (such as deconvolution algorithms, tomographic reconstruction, etc.) are disclosed. These scintillators are designed in order to increase robustness, minimize the required dose / scan time or even the number of scans required in scintillation imaging. These new designs optimize the scintillator for optimal reconstruction.

The invention provides a geometric random channel modeling method for satellite-ocean communication, and the method comprises the steps: S1, building a satellite-ocean communication simulation scene, and setting scene layout parameters; s2, initializing a satellite transmitting end orbit parameter, a receiving end position and a sea wave fluctuation parameter; s3, calculating large-scale parameters with consistent space; s4, calculating path loss, shadow fading, atmospheric absorption loss, ionospheric scintillation loss and rainfall loss according to the set receiving and transmitting end position information; s5, calculating a small-scale parameter according to angle extension in the generated large-scale parameter, initializing the position of a scattering cluster on the sea surface and the surface of the ship body, generating time delay and power of the cluster, and generating a channel coefficient by combining the loss calculated in the step S4; s6, updating the large-scale parameters and the small-scale parameters according to the motion of the transmitting and receiving end and the birth and extinguishment process of the cluster, and generating a new channel coefficient; and S7, calculating channel statistical characteristics according to the obtained channel coefficients.

The invention belongs to the technical field of organic radiation luminescence and radiation imaging, and discloses an aggregation-induced delayed fluorescence (AIDF) type organic scintillator material and a preparation method thereof, and a preparation method and application of a flexible organic scintillation film. The molecular structure of the material comprises carbonyl, methylene, sulfuryl and other connecting units, phthalonitrile is used as an acceptor unit, carbazole is used as a donor unit, an aggregation-induced excitation state is formed through space charge transfer among molecules, efficient AIDF luminescence and large Stokes shift characteristics are realized, the self-absorption phenomenon is effectively avoided, and the luminescent efficiency is improved. The X-ray fluorescence probe is suitable for a luminescence process under an X-ray excitation condition, the sensitivity of X-ray detection is remarkably improved, and the lowest detection limit can reach 276nGy.s <-1 > and is far superior to the 5.5 mu Gy.s <-1 > standard required by medical diagnosis. Besides, the flexible scintillator film prepared based on the material system radiates and emits light within the waveband range of 450-750 nm and is perfectly matched with the response area of a silicon-based detector, X-ray imaging with the high signal-to-noise ratio is achieved, and the imaging resolution is as high as 20.01 lp.mm <-1 >.

System, method, and instrumentalities are described herein for transmitting information optically. The optical source may be configured to generate a beam. The beam may include a series of light pulses. The beam of light may be modulated. A modulator may be configured to modulate the series of light pulses in response to a data transmission signal, thereby encoding transmission data into the series of light pulses. The modulated beam of light may be received and both amplified and filtered. The filtered beam of light may be transmitted from to a detector having a photoreceiver. The photoreceiver may be configured to extract the transmission data from the filtered beam of light.

The invention discloses a TDCR absolute measurement method for rapidly determining a Birk factor, which comprises the following steps: aiming at a scintillation liquid system of the Birk factor to be determined, manufacturing a radioactive sample source with the known activity A, injecting the radioactive sample source into a scintillation bottle, and putting the scintillation bottle into a liquid scintillation spectrometer; the method comprises the following steps of: initializing the value of a Birk factor, constructing a detection efficiency relational expression of three PMTs of PMTs, gradually changing the distance between a focusing electrode of each PMT and scintillation liquid to change the detection efficiency and a quenching indication parameter, iteratively optimizing the Birk factor by utilizing the detection efficiency relational expression, solving the optimal Birk factor and a corresponding efficiency value, and completing measurement. According to the TDCR absolute measurement method for rapidly determining the Birk factor, calibration of the scintillation liquid can be rapidly completed, subsequent absolute measurement is facilitated, and the convenience and accuracy of the absolute measurement method are greatly improved.

The invention discloses an ionospheric scintillation monitoring method based on a geodetic measurement receiver, which belongs to the technical field of satellite navigation, and comprises the following steps of: accurately eliminating non-scintillation errors by constructing an inter-station single-difference function model and an inter-station single-difference random model, extracting carrier phase residual errors by using a single epoch ambiguity fixing technology, and finally obtaining an ionospheric scintillation monitoring result. Establishing a reliable ionospheric scintillation monitoring index; according to the ionospheric scintillation monitoring method based on the geodetic measurement type receiver, high-precision real-time monitoring of ionospheric scintillation can be realized through a single-epoch ambiguity fixing technology under the condition of not depending on an external precision product, and reliable technical support is provided for space weather monitoring.

The invention discloses a three-color plastic scintillation optical fiber array and a preparation method and application thereof, and belongs to the technical field of plastic scintillation optical fiber arrays. The three-color plastic scintillation optical fiber array is composed of plastic scintillation optical fibers emitting red light, green light and blue light, and the three-color plastic scintillation optical fibers are arranged according to the color rule of a set pattern to form the three-color plastic scintillation optical fiber array. The optical fiber array is simple in structure, low in manufacturing cost and capable of being popularized and applied on a large scale. The three-color plastic scintillation optical fiber array has the characteristics of miniaturization, long-distance transmission and electromagnetic interference resistance, and is very suitable for radiation detection in a complex environment. Meanwhile, the optical fiber array covers red, green and blue wavelength bands, can be matched with more photoelectric detectors with different wavelength sensitivities, can realize high-resolution and long-distance imaging when being applied to X-ray imaging, can form different patterns under X-ray irradiation, and can be widely applied to the fields of radiation detection, industrial detection, medical imaging and the like.

Some embodiments of the invention pertain to generating (s10) and providing (s20) ionospheric disturbance information from navigation satellite system (NSS) reference stations or reference station system to NSS receivers or NSS receiver systems. Station-specific and / or satellite-specific ionospheric disturbance information may be obtained (s40) on the receiver side for mitigation purposes (s60, s70, s80) in the context of estimating parameters useful to determine a position. The ionospheric disturbance information may for example comprise ionospheric amplitude scintillation information, ionospheric phase scintillation information, and / or ionospheric delay gradient information. Systems, vehicles, and computer programs are also disclosed.

The invention relates to an alpha radiation detector (1) for measuring the radon concentration in the ambient air, comprising a housing (10) having a base (5) on which a hood (2) is arranged, which hood has a chamber (9) which is located therein, wherein the opaque housing (10) is designed in such a way that ambient air can penetrate into the chamber (9) from the outside, the alpha radiation detector further comprising an optical sensor (4). According to the invention, the hood (2) has an inner wall which is provided at least in part with a scintillation material (3) which generates light pulses (8) upon impingement of alpha particles (7), which light pulses are sensed by the optical sensor (4).

The embodiment of the invention provides a time detection device and method for a scintillation pulse signal, an electronic device and a medium, a system module determines the number of target threshold modules needing to be started for detection according to the estimated voltage amplitude of the scintillation pulse signal, and starts each target threshold module through a starting instruction; the flicker pulse signals are input into the target threshold modules in parallel, the flicker pulse signals and corresponding voltage threshold signals output by the voltage unit are connected to the input end of the threshold comparator, and comparison signals output by the threshold comparator are sent to the system module; and the system module determines each voltage threshold of the scintillation pulse signal and the corresponding detection time according to the comparison signal. According to the method, time detection can be carried out on the scintillation pulse signal, the real zero-crossing point of the scintillation pulse is obtained in a full-digital mode, the threshold comparator is used, meanwhile, the influence of baseline noise caused by too low threshold setting is avoided, and the obtained pulse detection time is more accurate.

The invention provides a pixelated flexible composite scintillation thin film based on a template-assisted nanoimprint technology and a preparation method and application of the pixelated flexible composite scintillation thin film. The preparation method of the pixelated flexible composite scintillation film comprises the following steps: preparing the flexible composite scintillation film; and constructing a periodic nanometer photon structure pattern on the flexible composite scintillation film by using a template-assisted nanoimprint technology to obtain the pixelated flexible composite scintillation film. According to the preparation method of the pixelated flexible composite scintillation film based on the template-assisted nanoimprint technology, the process is controllable, the preparation process flow is simplified, the production cost is reduced, the spatial resolution of the flexible composite scintillation film can be effectively improved, the imaging performance of the flexible scintillation film is greatly improved, and the application prospect is wide. Wide application prospects are realized in the fields of high-resolution X-ray imaging, radiation detection and wearable medical devices.

The invention discloses a foundation space ionosphere and troposphere integrated joint detection method and device, and belongs to the technical field of satellite navigation, and the method comprises the steps: detecting the vertical total electron content of an ionosphere: extracting the inclined total electron content of the ionosphere at an ionosphere puncture point, and converting the inclined total electron content into the vertical total electron content of the ionosphere; detecting a foundation Beidou ionosphere disturbance index; and detecting an ionosphere phase scintillation index, a troposphere zenith total delay, a troposphere precipitable amount and an ionosphere amplitude scintillation index, and outputting ground-based Beidou space ionosphere and troposphere integrated joint detection parameters. The method effectively improves the reliability, robustness and meteorological perception capability of a navigation positioning system in a complex atmospheric environment, and is especially suitable for special environmental conditions such as severe convection weather, typhoon landing, violent disturbance of an ionized layer and the like.

A method for determining neutron flux by utilizing a portable Radionuclide Identification Device (RID) as it is used in homeland security applications is provided. The RID has an inorganic crystal comprising iodine, a light detector and electronics for the evaluation of the output signals of the light detector. The method includes a step of detecting, with the light detector, light emitted by the crystal following the interaction of nuclear radiation with the crystal. The intensity of the light measured is a function of the energy deposed in the crystal by said nuclear radiation during the interaction with the crystal.

The invention discloses an ionospheric scintillation monitoring method based on a lightweight GNSS receiver, which belongs to the technical field of navigation, and comprises the following steps: extracting data through a lightweight GNSS receiver board card, carrying out detrending processing on signal intensity and carrier phase measurement values, calculating a scintillation index and adjusting parameters according to user requirements, and recording scintillation data according to a threshold value. Flicker types are distinguished through interference identification, and regional networking monitoring and visualization are realized through a cloud server; according to the ionospheric scintillation monitoring method based on the lightweight GNSS receiver, flexible monitoring, accurate identification, regional collaboration and data full-period service are realized, and the flexibility, accuracy and data value of ionospheric scintillation monitoring are effectively improved.

The invention provides a rare earth silicon germanate scintillating material and a preparation method and application thereof, in particular to a rare earth silicon germanate scintillating material with high thermal stability and strong radiation resistance and a preparation method and application thereof, the general formula of the rare earth silicon germanate scintillating material with high thermal stability and strong radiation resistance is RE2 (1-x-delta / 2) Ce2xGedeltaSi (1-y + delta) Gey-deltaOz, in the formula, 0 lt; x is more than or equal to 0.05, y is more than or equal to 0.15 and less than or equal to 0.5, delta is more than or equal to 0 and less than or equal to 10 <-4 >, z is more than or equal to 4.95 and less than or equal to 5.05, RE represents a rare earth element, and the rare earth element is selected from at least one of lanthanum (La), lutetium (Lu), yttrium (Y) and gadolinium (Gd). The rare earth silicon germanate scintillating material provided by the invention has the characteristics of strong radiation damage resistance, high scintillation light output, low afterglow and the like while greatly improving the thermal stability, and can be used in occasions with extremely high requirements on the thermal stability or radiation resistance of the material, such as high-energy physical experiments, nuclear medicine imaging, oil exploration wells and the like.

The invention discloses a micron-sized ultrahigh-resolution flight time neutron imaging detector based on a boron nitride film scintillation screen, and the detector comprises the boron nitride film scintillation screen which is used for absorbing neutron beams and generating scintillation light; the light path system is used for collecting the scintillation light, amplifying the scintillation light and projecting the amplified scintillation light to a photosensitive chip of a time-resolved high-speed camera; and the time-resolved high-speed camera is used for receiving the scintillation light processed by the light path system and recording photon information. According to the invention, micron-level spatial resolution and sub-microsecond time resolution can be realized. The method can be widely applied to the field of neutron imaging.

This disclosure provides a microcrystalline scintillation glass array and a scintillator detector, relating to the field of radiation detection technology. The microcrystalline scintillation glass array includes: at least one layer of microcrystalline scintillation glass array, each layer comprising multiple microcrystalline scintillation glasses, each microcrystalline scintillation glass comprising a glass substrate and multiple microcrystals coated on the glass substrate; wherein the fabrication process of the microcrystalline scintillation glass includes incorporating microcrystals into the glass, and the material used to form each microcrystal includes a scintillator. Since the scintillator in the microcrystalline scintillation glass array is only incorporated into the glass in the form of microcrystals, the amount of scintillator required to fabricate the microcrystalline scintillation glass array is small, resulting in low cost. Furthermore, in the microcrystalline scintillation glass, the glass coating of the microcrystals provides a sealed environment for the microcrystals, making them less prone to deliquescence, and the protective effect of the glass broadens the application environment of the microcrystalline scintillation glass.

The invention discloses an environmental radon concentration detector based on a scintillator chamber, and the detector comprises a scintillation chamber in which a sampled radon-containing gas enters the scintillation chamber through a gas inlet, and an alpha ray generated by radon decay reacts with ZnS (Ag) to generate an optical signal; the photomultiplier is used for converting an optical signal into an electric signal; the pre-amplifier is used for amplifying and shaping the electric signal to obtain an amplified electric signal; the signal acquisition module is used for acquiring the amplified electric signal; and the concentration calculation module is used for calculating the radon concentration in the environment according to the amplified electric signal in combination with the decay law of the radon and the daughters thereof and the measurement time set by the user. According to the invention, radon and daughter decayed alpha rays in sampling gas react with the coating of the scintillation chamber to serve as the basis of radon concentration calculation, and the environmental radon concentration detection accuracy is improved from the internal structure design of the chamber.

The embodiment of the invention provides a full-automatic low-background liquid scintillation analyzer. The full-automatic low-background liquid scintillation analyzer comprises an analyzer frame body, a sample bottle storage device, a measuring chamber and an active shielding device, the measuring chamber comprises a three-pair coincidence three-way light chamber and a three-tube coincidence photomultiplier tube, and a liquid flash bottle provided by the sample bottle storage device can be contained in the three-pair coincidence three-way light chamber; the three-tube coincidence photomultiplier is horizontally arranged along the circumferential direction of the three-double coincidence three-way light chamber, and a first measuring probe of the three-tube coincidence photomultiplier penetrates into the three-double coincidence three-way light chamber; the active shielding device comprises plastic flashes and two common photomultipliers along the plastic flashes, the plastic flashes are arranged on the three double-coincidence three-way light chambers and used for converting environmental radiation in the three double-coincidence three-way light chambers into electric signals, and the common photomultipliers are horizontally arranged in the circumferential direction of the plastic flashes and can penetrate into the plastic flashes respectively. The number of the to-be-detected samples is determined according to the mixed solution of the to-be-detected samples and the scintillation solution, external radioactive interference can be actively eliminated through the active shielding device, and the detection accuracy is improved.