308 results about "Scintillation crystals" patented technology

A positron emission tomography (PET) scanner includes a plurality of gamma radiation detector modules arranged to form a detector ring. Each detector module includes an array of scintillator detectors. Each scintillator detector comprises a monolithic scintillation crystal and a plurality of photodetector arrays, such as silicon photomultipliers (SiPMs). A photodetector array is positioned on at least two nonparallel faces of each scintillation crystal. In some examples, a photodetector array is positioned on each of three orthogonal faces of each scintillation crystal.

A positron emission tomography (PET) scanner includes a plurality of gamma radiation detector modules arranged to form a detector ring. Each detector module includes an array of scintillator detectors. Each scintillator detector comprises a monolithic scintillation crystal and a plurality of photodetector arrays, such as silicon photomultipliers (SiPMs). A photodetector array is positioned on at least two nonparallel faces of each scintillation crystal. In some examples, a photodetector array is positioned on each of three orthogonal faces of each scintillation crystal.

The invention relates to the field of crystal detection, and discloses a multifunctional comprehensive scintillation crystal and semiconductor material energy spectrum test system, which comprises a crystal adaptation module for judging the type and size of a placed crystal through an optical identification and parameter matching mechanism, and a signal acquisition module for amplifying, filtering and digitally processing an acquired signal, the signal correction module is used for correcting waveform distortion and baseline drift through a dynamic gain adjustment algorithm of a low-noise pre-amplifier and a multi-channel pulse analyzer; the data analysis module is used for generating an energy spectrum curve according to input signals and calculating energy resolution, counting rate, light attenuation time or carrier mobility, and the environment calibration module is used for dynamically evaluating shading degree, environment light, temperature and electromagnetic interference through an optical sensor and a temperature and humidity detector in the camera obscura and outputting updated calibration parameters. The method has the advantages of improving the detection efficiency, precision and consistency.

The invention discloses a personal dosimeter capable of nuclide identification, and the dosimeter comprises a scintillation detector which is composed of a scintillation crystal and SiPM and captures an energy spectrum signal of a ray; the signal amplifier receives the voltage signal output by the SiPM and preprocesses and amplifies the voltage signal; the multichannel analyzer is used for receiving the amplified signal output by the signal amplifier and realizing energy spectrum acquisition in a target energy range; and the MCU receives the signals acquired by the multichannel analyzer and performs energy spectrum analysis. According to the invention, the scintillation detector based on SiPM and scintillation crystals is used, so that the small size and high sensitivity of the personal dosimeter are realized; according to the multi-channel analyzer, the multi-channel analyzer capable of setting the energy range is realized through the ADC and the comparator, and the design of a peripheral circuit is extremely simplified; the simplified nuclide identification method is designed based on prior information, the range of a nuclide library is narrowed, and the requirements of nuclide identification in a specified application scene for the computing power of a system and the complexity of an analog circuit are further reduced.

The invention belongs to the technical field of artificial crystals and radiation detection, and relates to a method for improving the performance of a rare earth orthosilicate scintillation crystal. The method for improving the performance of the rare earth orthosilicate scintillation crystal comprises the following steps: carrying out corrosion, plasma injection and annealing diffusion on the rare earth orthosilicate scintillation crystal, and finally realizing the improvement of the performance of the rare earth orthosilicate scintillation crystal.

The invention relates to a preparation method of a cerium-doped lutetium yttrium silicate crystal, and relates to the technical field of scintillation crystal preparation. Compared with a traditional Czochralski method, the cerium-doped lutetium yttrium silicate is prepared through a flame fusion method, the growth speed of the flame fusion method is 15-20 mm / h, the growth rate is higher, consumable items such as an iridium crucible are not needed, mutual reaction between a high-temperature melt and the crucible is avoided, the cost is effectively reduced, and the cerium-doped lutetium yttrium silicate is obtained. The limitation of a crucible material on preparation of high-melting-point oxide crystals is eliminated, the crystal quality is improved, and the growth period is short.

The invention belongs to the technical field of scintillation materials, and particularly relates to a chromium ion doped near-infrared scintillation crystal and a preparation method and application thereof. The chromium ion-doped near-infrared scintillation crystal has a molecular formula of A3B2-xCrxC3O12, x is greater than or equal to 0.005 and less than or equal to 0.1, and after a chromium ion-doped ultraviolet-visible light inorganic scintillator is adopted, light is emitted at the wavelength of 650-950 nm and has good wavelength matching with a silicon photoelectric detector. Besides, single crystal growth is carried out by adopting a Czochralski method, the crystal growth process is optimized, the ion doping concentration is regulated and controlled, the scintillation performance of the chromium ion doped near-infrared scintillation crystal in the near-infrared band is improved, the requirement of the chromium ion doped near-infrared scintillation crystal in the radiation detection field is further met, and the problem that an existing scintillation crystal is low in transparency is solved.

The invention discloses a polishing solution for scintillation crystals and a preparation method of the polishing solution. The polishing solution comprises the following components in percentage by mass: 0.8%-1.2% of silicon dioxide abrasive particles; 15%-25% of ethanol; 4%-6% of deionized water; and the balance of glycerol. Glycerin is selected as a base solution of the polishing solution, the polishing solution has the advantages of stability, no toxicity, no stimulation and the like, deliquescence of scintillation crystals can be avoided in the polishing process, and the stability of the scintillation crystals is ensured. In order to improve the mechanical effect of the polishing pad, silicon dioxide abrasive particles are added into the polishing solution. The silicon dioxide abrasive particles have a large number of hydroxyl groups and can improve the hydrophilicity of the polishing solution. The hydroxyl groups form hydrogen bonds with hydroxyl groups in glycerol and ethanol, and form hydrogen bonds with water molecules in the polishing solution to generate intermolecular force, so that the silicon dioxide abrasive particles are more uniformly dispersed in the whole polishing solution. And ethanol is used as a diluent to reduce the viscosity of glycerol, so that the flowability of the polishing solution is improved, the abrasive particle dispersity is improved, and the conveying performance of the peristaltic pump is improved.

The invention relates to a micro-channel flow boiling in-situ measurement method, which comprises the following steps of: 1) establishing a micro-channel flow boiling test system (17), and testing to ensure the sealing performance and the stability of the test system; 2) building a synchrotron radiation X-ray imaging system; 3) performing a pre-test to ensure that synchrotron radiation X-rays can penetrate through the micro-channel, pass through the scintillation crystal (3) and the reflector (4) and then are received by the high-speed camera; (4) micro-channel flow boiling tests under different test working conditions are carried out, and after it is monitored that the wall surface temperature reaches an approximate steady state, the synchrotron radiation X-ray imaging system is used for shooting the flow boiling phenomenon in the micro-channel; meanwhile, a temperature and pressure sensor in the micro-channel flow boiling test system is used for collecting wall surface temperature and inlet and outlet pressure, and in-situ measurement results of the wall surface temperature and the inlet and outlet pressure are obtained. Compared with the prior art, the method has the advantages of solving the problem of view angle limitation existing in a micro-channel flow boiling observation means and the like.

The invention relates to a cerium ion doped high-entropy fluoride scintillation crystal and a preparation method and application thereof. The preparation method comprises the following steps: taking single crystal particles or powder of LaF3, GdF3, CaF2, SrF2, BaF2 and CeF3 as raw materials, doping Ce ions, uniformly grinding to obtain a matrix material, vacuumizing, carrying out high-temperature sintering, ensuring that the matrix material is completely melted and impurities are removed, slowly cooling, carrying out crystal growth, and cooling to room temperature to obtain the cerium ion doped high-entropy fluoride scintillation crystal. The chemical formula of the high-entropy fluoride scintillation crystal is Ce: M1M2CaSrBaF12, wherein M1 and M2 are any two of Y, Lu, Gd, La, Lu, Sc and Ce. Compared with the prior art, the LaGdCaSrBaF12 high-entropy crystal prepared by the invention has lower phonon energy and smaller 5d energy level cleavage, and can greatly reduce the non-radiative transition probability of the 5d energy level of Ce < 3 + > ions. In addition, the disorderly distributed mixed crystal also regulates and controls the local coordination structure of Ce < 3 + > ions on the scales of atoms, molecules and groups, so that true disorder is achieved.

The invention discloses a large-area scintillation crystal array and a preparation method thereof. The array is assembled by adopting a plurality of slotted small crystal blocks, the plane precision of the array is ensured by adopting a gasket during assembly, a wafer is positioned by adopting a splicing clamp so as to ensure the geometric dimension precision, and the splicing efficiency is remarkably improved by adopting UV glue for bonding. Compared with a method for manufacturing the array by using a large-area crystal block, the method not only reduces the requirements on the crystal quality and the growth size, but also effectively utilizes the redundant material of the crystal, and realizes the maximum utilization of resources. And meanwhile, compared with an array assembled by adopting a single crystal strip, the array assembling efficiency is remarkably improved, the manufacturing period is short, the efficiency is high, the product delivery speed is increased, and the good application prospect is achieved.

Apparatuses and methods as described herein can be used to grow a β-Ga2O3 based single crystal using an Edge-defined film fed growth (EFG) method. The method can include bringing a seed crystal in contact with a Ga2O3 base melt, pulling the seed crystal to grow the β-Ga2O3 based single crystal, wherein the β-Ga2O3 based single crystal has a (010) crystallographic orientation as it is being grown, and cooling the β-Ga2O3 based single crystal after it has reached a length that is greater than 40mm. In one embodiment, the method includes growing the scintillation crystal without defects.

Tapered scintillator modules and detection devices having tapered scintillator modules in at least the end that contacts an optical sensor where the taper depends on the location of the scintillator module within the active area of the optical sensor is provided. Tapering of the scintillator modules may be close to the interface between the optical sensor and the module to minimize light leak to neighboring pixels at the interface while still allowing the detection device to retain high geometric efficiency and sensitivity to incident gamma rays since the distal end may not be tapered, which has a highest probability for gamma ray interaction based on Beer-Lambert law for photoelectric absorption.

A positron emission tomography (PET) scanner may include a plurality of gamma radiation detector modules arranged to form a detector ring. Each detector module may include an array of elongated scintillation crystals. With respect to the detector ring, each elongated scintillation crystal includes a proximal end-face, two axially oriented lateral faces, two transaxially oriented lateral faces, and a distal end-face radially oriented into the detector ring to receive a gamma photon. An array of photosensors is positioned along a first of the axially oriented lateral faces of each elongated scintillation crystal to detect scintillation photons. A reflective material is positioned on the proximal end-face, the distal end-face, the transaxially oriented lateral faces, and a second of the axially oriented lateral faces of each elongated scintillation crystal to internally reflect scintillation photons. In various embodiments, a dual-channel processing circuit provides distinct timing and energy signals from the photosensors.

A positron emission tomography (PET) scanner includes multiple gamma radiation detector modules arranged to form a detector ring. Each detector module includes an array of elongated scintillation crystals. With respect to the detector ring, each elongated scintillation crystal includes a proximal end face, two axially-oriented side faces, two cross-axially-oriented side faces, and a distal end face oriented radially into the detector ring to receive gamma photons. An array of photosensors is disposed along a first of the axially-oriented side faces of each elongated scintillation crystal to detect scintillation photons. Reflective material is disposed on a second of the proximal end face, the distal end face, the cross-axially-oriented side face, and the axially-oriented side face of each elongated scintillation crystal to internally reflect scintillation photons. In various embodiments, a dual-channel processing circuit provides separate timing and energy signals from the photosensors.

A portable gamma radiation directional detector comprises a housing 6, a main crystal 7, a cylindrical sub-crystal 8, a donut-shaped sub-crystal 9 and a photomultiplier tube 10. The main crystal 7 is a cylindrical NaI (TL) scintillation crystal, the cylindrical sub-crystal 8 is a cylindrical CsI (TL) scintillation crystal, and the donut-shaped sub-crystal 9 is a plastic donut-shaped scintillation crystal. The main crystal 7, the cylindrical sub-crystal 8 and the donut-shaped sub-crystal 9 are coaxially mounted on the end face of the photomultiplier tube 10 in the housing 6. The present invention reduces the weight of the gamma radiation directional detector, solves its long-standing unresolved weight problem, and improves its directional performance. It has the characteristics of simple and light structure, reasonable design, good directional performance, etc.

A scintillation crystal can include a rare earth silicate, an activator, and a Group 2 co-dopant. In an embodiment, the Group 2 co-dopant concentration may not exceed 200 ppm atomic in the crystal or 0.25 at % in the melt before the crystal is formed. The ratio of the Group 2 concentration / activator atomic concentration can be in a range of 0.4 to 2.5. In another embodiment, the scintillation crystal may have a decay time no greater than 40 ns, and in another embodiment, have the same or higher light output than another crystal having the same composition except without the Group 2 co-dopant. In a further embodiment, a boule can be grown to a diameter of at least 75 mm and have no spiral or very low spiral and no cracks. The scintillation crystal can be used in a radiation detection apparatus and be coupled to a photosensor.

The utility model discloses a scintillation crystal packaging device, and relates to the scintillation crystal packaging technology field, the scintillation crystal packaging device comprises a pedestal, the top of the pedestal is provided with a damping mechanism used for reducing vibration, the damping mechanism is provided with an outer barrel, the inner wall of the outer barrel is provided with an inner barrel in a sliding manner, the outer barrel is provided with a cover plate in a sliding manner, and the cover plate is provided with an opening. A handle is arranged on the inner barrel in a sliding mode, the handle is arranged on the cover plate in a sliding mode, a sealing gasket is arranged at the bottom of the cover plate and makes contact with the outer barrel and the inner barrel, a rubber gasket is arranged on the cover plate, the handle makes contact with the rubber gasket, and a fixing mechanism used for applying pressure to the cover plate is arranged on the base. The fixing mechanism comprises two fixing frames, the two fixing frames are fixedly installed on the two sides of the outer barrel respectively, and a two-way screw rod is rotationally installed in the fixing frame on the front side, so that the scintillation crystal can be packaged conveniently, damping protection can be conducted on the scintillation crystal, operation is easy, and practicability is high.

The present application discloses an image reconstruction method, system, detection device, electronic device, and storage medium, relating to the field of data processing. The image reconstruction method includes: obtaining the TOF resolution of some response lines based on prior information; obtaining the time resolution of all scintillation crystals based on the TOF resolution of the partial response lines and a preset model; obtaining the TOF resolution of the remaining response lines based on the time resolution of all scintillation crystals and the preset model; and reconstructing the image based on all TOF resolutions and a first preset algorithm. The solution of the present application performs differentiated processing on the TOF resolutions of different response lines, especially associating the TOF resolution of the response line with the time resolution of the corresponding scintillation crystal, accurately estimating the TOF resolution of the response line, and effectively improving the quality of image reconstruction.

Apparatuses and methods as described herein can be used to grow a β-Ga2O3 based single crystal using an Edge-defined film fed growth (EFG) method. The method can include bringing a seed crystal in contact with an alumina doped Ga2O3 base melt, pulling the seed crystal to grow the β-Ga2O3 based single crystal, and cooling the β-Ga2O3 based single crystal after it has reached a length that is greater than 40 mm. In one embodiment, the method includes growing the scintillation crystal without defects.

The application discloses a same-position integrated double neutron detector, a logging instrument and an application method, and belongs to the field of uranium ore exploration logging. The double neutron detector comprises first and second scintillation crystals which are both sensitive to thermal neutrons and are arranged in a face-to-face manner, a photoelectric converter and a supporting portion; the first and second scintillation crystals and the photoelectric converter are arranged along the same axis to form a detection portion which is read out by a common light path, and the supporting portion is fixedly arranged outside the detection portion and supports the detection portion to be an integral component; a slow moderation layer is arranged on the outer wall surface of the first scintillation crystal except the bonding area; the logging instrument is provided with the double neutron detector, and the first and second scintillation crystals are calibrated in the same thermal neutron field during application; the spatial consistency error is eliminated through the same-position design of the double scintillation crystals; the hardware structure of the detector electronics is simplified through the common light path reading out design; and the detector module is convenient to integrate.

Apparatuses and methods as described herein can be used to grow a β-Ga2O3 based single crystal using an Edge-defined film fed growth (EFG) method. The method can include bringing a seed crystal in contact with a Ga2O3 base melt, pulling the seed crystal to grow the β-Ga2O3 based single crystal, wherein the β-Ga2O3 based single crystal has a (010) crystallographic orientation as it is being grown, and cooling the β-Ga2O3 based single crystal after it has reached a length that is greater than 40 mm. In one embodiment, the method includes growing the scintillation crystal without defects.

The present application discloses an image reconstruction method, system, detection equipment, electronic equipment and storage medium, which relate to the field of data processing. The image reconstruction method includes: obtaining the TOF resolution of some response lines based on prior information; obtaining the time resolution of all scintillation crystals based on the TOF resolution of the said part of the response line and the incident angle of the corresponding photon; obtaining the TOF resolution of the remaining response lines based on the time resolution of all scintillation crystals and the incident angle of the photon; and reconstructing the image based on all TOF resolutions and a first preset algorithm. The solution of the present application performs differentiated processing on the TOF resolutions of different response lines, especially associating the TOF resolution of the response line with the time resolution of the corresponding scintillation crystal and the incident angle of the photon, accurately estimating the TOF resolution of the response line, and effectively improving the quality of image reconstruction.

This utility model relates to the field of polishing device technology, and in particular to a polishing device for scintillation crystal surface. It includes a polishing frame for polishing a pressure-bearing scintillation crystal, a flexible clamping module located at the top corners of the polishing frame to flexibly hold the scintillation crystal, a circulation tank for circulating and filtering coolant connected to the bottom of the polishing frame, and polishing processing components for polishing the scintillation crystal surface corresponding to the polishing frame. The flexible clamping module uses flexible clamping blocks with floating blocks, and the clamping force is dynamically adjusted by internal magnetic blocks and electromagnets. Combined with spring rubber dampers to absorb vibration, it avoids edge chipping caused by stress concentration at the crystal edge. The bottom of the polishing sleeve is designed as a curved panel, forming a gradual contact with the crystal surface to reduce sudden changes in edge pressure. A filter plate inside the polishing frame pre-filters debris, and a filter column in the circulation tank further purifies the coolant.

The invention provides a detector of an SPECT imaging system, the SPECT imaging system and an SPECT imaging method. The detector of the SPECT imaging system comprises a plurality of detector units, and the plurality of detector units are arranged in a first direction; each detector unit comprises a plurality of detector modules arranged in a second direction, the second direction is perpendicular to the first direction, each detector module comprises a scintillation crystal array, an SiPM detector array and a preprocessing device which are sequentially arranged in a third direction, and the third direction, the first direction and the second direction are perpendicular to one another; the scintillation crystal array comprises a plurality of scintillation crystal blocks arranged in an array, the SiPM detector array comprises a plurality of SiPM detector pixels arranged in an array, and the scintillation crystal blocks and the SiPM detector pixels are arranged in a one-to-one correspondence manner. According to the detector, the spatial uniformity is remarkably improved, and the imaging quality is further improved.

The invention discloses a near-infrared scintillation crystal and a preparation method thereof. The chemical formula of the scintillation crystal is Cs3Ce1-yX6: ySb, wherein X is selected from at least one of Cl and Br; the value range of y is more than or equal to 0.001 and less than or equal to 0.06. The scintillation crystal is prepared by adopting a Bridgman-Stockbarger method, can emit broadband near-infrared light with the wavelength of 800-1000nm under the excitation of high-energy rays or high-energy particles, and is matched with the detection wavelength of an APD (Avalanche Photo Diode) and an SiPM (Silicon Particulate Matrix) detector with high quantum efficiency.

The present invention belongs to the field of nuclear power maintenance technology, and specifically relates to a γ-β composite detection device. The absorption rate of the first scintillation crystal to β rays is higher than that to γ ​​rays, so that the first photomultiplier tube and the first signal processing unit can detect β rays according to the light emitted by the first scintillation crystal, and the absorption rate of the second scintillation crystal to β rays is lower than that to γ ​​rays, so that the second photomultiplier tube and the second signal processing unit can detect γ rays according to the light emitted by the second scintillation crystal, thereby realizing the composite detection of γ and β rays, so as to assist in determining the damage of fuel assemblies at different time of leaving the stack. In addition, the first scintillation crystal is used as a detection chamber, which can effectively store the gas to be tested, and can make the first scintillation crystal more fully receive the irradiation of the rays released by the gas to be tested from the inside to the outside, thereby making the γ-β composite detection device more sensitive to the β rays released by the gas to be tested.

1. The name of the design product: multifunctional in-situ processing unit. 2. The use of the design product: applied to the in-situ processing unit in the NaI (6Li, Tl) scintillation crystal neutron gamma online monitoring system. 3. The design points of the design product: the combination of shape and pattern. 4. The picture or photo that best shows the design points: perspective view 1.

The invention relates to the technical field of SPECT detection equipment, and provides an SPECT-CT equipment probe device and a heat dissipation method applying the SPECT-CT equipment probe device, and the SPECT-CT equipment probe device comprises a heat insulation plate, a heat insulation outer cover, and a plurality of groups of scintillation crystals, a plurality of groups of SiPM sensors, a plurality of groups of SiPM temperature detectors, a refrigeration plate, a plurality of groups of semiconductor refrigeration sheets and a control circuit board which are arranged in the heat insulation outer cover; the multiple sets of semiconductor chilling plates and the multiple sets of SiPM sensors are correspondingly arranged in the vertical direction, so that one set of semiconductor chilling plates corresponds to one set of SiPM sensors, and one set of scintillation crystals and one set of SiPM temperature detectors are used in a matched mode. The control circuit board can independently control the refrigeration power of each group of semiconductor refrigeration sheets according to different temperatures of each group of SiPM sensors, so that each group of SiPM sensors can be cooled in a targeted manner, the temperature balance and stability of each group of SiPM sensors are ensured, the performance consistency of each group of SiPM sensors is ensured, and the data acquisition consistency and the image quality are ensured.

Apparatuses and methods as described herein can be used to grow a β-Ga2O3 based single crystal using an Edge-defined film fed growth (EFG) method. The method can include bringing a seed crystal in contact with an alumina doped Ga2O3 base melt, pulling the seed crystal to grow the β-Ga2O3 based single crystal, and cooling the β-Ga2O3 based single crystal after it has reached a length that is greater than 40mm. In one embodiment, the method includes growing the scintillation crystal without defects.