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Journal of Semiconductors 2024年第3期45卷 71-75页

作者： Tingting Shi Yuanbin Fan Zhengyu Yan Lai Zhou Yang Ji Zhiliang Yuan Beijing Academy of Quantum Information Sciences Beijing 100193China Institute of Semiconductors Chinese Academy of SciencesBeijing 100083China College of Materials Science and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 100049China

We demonstrate the photon-number resolution(PNR)capability of a 1.25 GHz gated InGaAs single-photon avalanche photodiode(APD)that is equipped with a simple,low-distortion ultra-narrowband interference circuit for the rejection of its background capacitive *** discriminating the avalanche current amplitude,we are able to resolve up to four detected photons in a single detection gate with a detection efficiency as high as 45%.The PNR capability is limited by the avalanche current saturation,and can be increased to five photons at a lower detection efficiency of 34%.The PNR capability,combined with high efficiency and low noise,will find applications in quantum information processing technique based on photonic qubits.

关键词： single photon avalanche diode(APD) photon number resolution(PNR) detection efficiency

detection efficiency evaluation for a large area neutron sensitive microchannel plate detector

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Chinese Physics C 2016年第9期40卷 102-106页

作者：王一鸣田阳杨祎罡刘仁潘京生王学武张智 Department of Engineering Physics Tsinghua University Key Laboratory of Particle & Radiation Imaging (Tsinghua University) Ministry of Education Nanjing Branch North Night Vision Tech.Co. Ltd.

In this paper, the detection efficiency of a large area neutron sensitive microchannel plate detector has been evaluated. A ^6LiF/ZnS scintillator detector 65 mm in diameter and 0.32 mm in thickness, with product code,EJ426HD2, produced by Eljen Technology, was employed as the benchmark detector. The TOF spectra of these two detectors were simultaneously measured and the energy spectra were then deduced to calculate the detection efficiency curve of the ^nMCP detector. Tests show the detection efficiency@25.3 me V thermal neutrons is 34% for this ^nMCP detector.

关键词： microchannel plate neutron detector detection efficiency

Peripheral zone PSA density:a predominant variable to improve prostate cancer detection efficiency in men with PSA higher than 4 ng ml^(-1)

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Asian Journal of Andrology 2021年第4期23卷 415-420页

作者： Cheng Wang Yue-Yang Wang Shi-Yuan Wang Ji-Xiang Ding Mao Ding Yuan Ruan Xiao-Hai Wang Yi-Feng Jing Bang-Min Han Shu-Jie Xia Chen-Yi Jiang Fu-Jun Zhao Department of Urology Jiangsu Jiangyin People's HospitalJiangyin 214400China Department of Urology Shanghai General Hospital of Nanjing Medical UniversityShanghai 200080China Department of Urology Shanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 200080China Department of Urology Kashgar Prefecture Second People's HospitalKashi 844000China

To improve the diagnostic efficiency of prostate cancer(PCa)and reduce unnecessary biopsies,we defined and analyzed the diagnostic efficiency of peripheral zone prostate-specific antigen(PSA)density(PZ-PSAD).Patients who underwent systematic 12-core prostate biopsies in Shanghai General Hospital(Shanghai,China)between January 2012 and January 2018 were retrospectively identified(n=529).Another group of patients with benign prostatic hyperplasia(n=100)were randomly preselected to obtain the PSA density of the non-PCa cohort(N-PSAD).Prostate volumes and transition zone volumes were measured using multiparameter magnetic resonance imaging(mpMRI)and were combined with PSA and N-PSAD to obtain the PZ-PSAD from a specific *** operating characteristic(ROC)curve analysis was used to assess the PCa detection efficiency in patients stratified by PSA level,and the area under the ROC curve(AUC)of PZ-PSAD was higher than that of PSA,PSA density(PSAD),and transition zone PSA density(TZ-PSAD).PZ-PSAD could amend the diagnosis for more than half of the patients with inaccurate transrectal ultrasonography(TRUS)and mpMRI *** TRUS and mpMRI findings were ambiguous to predict PCa(PIRADS score≤3),PZ-PSAD could increase the positive rate of biopsy from 21.7%to 54.7%,and help 63.8%(150/235)of patients avoid unnecessary prostate *** patients whose PSA was 4.0–10.0 ng ml^(−1),10.1–20.0 ng ml^(−1),and>20.0 ng ml^(−1),the ideal PZ-PSAD cut-off value for predicting clinically significant PCa was 0.019 ng ml^(−2),0.297 ng ml^(−2),and 1.180 ng ml^(−2),respectively(sensitivity>90%).Compared with PSA,PSAD,and TZ-PSAD,the efficiency of PZ-PSAD for predicting PCa is the highest,leading to fewer missed diagnoses and unnecessary biopsies.

关键词： benign prostate hyperplasia detection efficiency peripheral zone prostate-specific antigen density prostate biopsy prostate-specific antigen prostatic neoplasm

EVALUATION OF GROUND STROKE DENSITY DISTRIBUTION AND LIGHTNING detection efficiency IN BEIJING-TIANJIN-HEBEI AREA

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Acta meteorologica Sinica 1996年第3期10卷 346-355页

作者：陶善昌孟青 University of Science and Technology of China Hefei 230026 Chinese Academy of Meteorological Sciences Beijing 100081

It is possible to understand the lightning activities in a specific region and compare test results of different apparatus only when a reliable evaluation of detection efficiency distribution pertaining to a particular lightning location system(LLS)is available. Based on the data in *** approximate evaluation of detection efficiency spatial distribu- tion for single-station lightning location system(M-LDARS)and LLP three-station lightning loca- tion system in Beijing-Tianjin-Hebei area is presented in the paper,showing that the average detec- tion efficiencies are smaller than 48% and 46% *** addition,the article offers an eval- uation of spatial distribution of ground stroke density(D_g)and positive stroke percentage,indicat- ing that six high stroke density zones exist along the southeastern sides of the Taihang and Yan- shan *** stroke density of mountainous region is higher than that of the plain region, in contrast to the case of positive stroke ***,it is shown that within a radius of 250 km,the average of D_g is 1.2(km^(-2) a^(-1))while the average positive stroke percentage is 10.9%. Finally,the paper proposes a possible test method of accurately evaluating the spatial distribution of detection efficiency(A).

关键词： lightning location system detection efficiency ground stroke density spatial distribution

Comparison of thermal neutron detection ef f iciency of 6Li scintillation glass and 3He gas proportional tube

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Chinese Physics C 2013年第10期37卷 33-38页

作者：徐明唐志成陈国明陶军全 Institute of High Energy Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

We report on a comparison study of the 3He gas proportional tube and the 6Li incorporated scintillation glasses on thermal neutron detection efficiency. Both 3He and 6Li are used commonly for thermal neutron detection because of their high neutron capture absorption coefficient. By using a neutron source 252Cf and a paraffin moderator in an alignment system, we can get a small beam of thermal neutrons. A flash ADC is used to measure the thermal neutron spectrum of each detector, and the detected number of events is determined from the spectrum, then we can calculate the detection efficiency of different detectors. Meanwhile, the experiment has been modeled with GEANT4 to validate the results against the Monte Carlo simulation.

关键词： thermal neutron detection efficiency 6Li incorporated scintillation glass 3He gas proportional tube,flash ADC GEANT4

Simulation of an imaging system for internal contamination of lungs using MPA-MURA coded-aperture collimator

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Nuclear Science and Techniques 2021年第2期32卷 58-69页

作者： Ting Zhang Lei Wang Jing Ning Wei Lu Xiao-Fei Wang Hai-Wei Zhang Xian-Guo Tuo Chengdu University of Technology Chengdu 610059China Sichuan University of Science&Engineering Zigong 643000China Beijing Institute of Radiation Medicine Beijing 100850China

The nuclides inhaled during nuclear accidents usually cause internal contamination of the lungs with low *** a parallel-hole imaging system,which is widely used in medical gamma cameras,has a high resolution and good image quality,owing to its extremely low detection efficiency,it remains difficult to obtain images of inhaled lung *** this study,the Monte Carlo method was used to study the internal lung contamination imaging using the MPA-MURA coded-aperture *** imaging system consisted of an adult male lung model,with a mosaicked,pattern-centered,and anti-symmetric MURA coded-aperture collimator model and a CsI(Tl)detector *** MLEM decoding algorithm was used to reconstruct the internal contamination image,and the complementary imaging method was used to reduce the number of *** full width at half maximum of the I-131 point source image reconstructed by the MPAMURA coded-aperture imaging reached 2.51 mm,and the signal-to-noise ratio of the simplified respiratory tract source(I-131)image reconstructed through MPA-MURA coded-aperture imaging was 3.98 *** the spatial resolution of MPA-MURA coded-aperture imaging is not as good as that of parallel-hole imaging,the detection efficiency of PMA-MURA coded-aperture imaging is two orders of magnitude higher than that of parallel-hole collimator *** the low activity level of internal lung contamination caused by nuclear accidents,PMA-MURA coded-aperture imaging has significant potential for the development of lung contamination imaging.

关键词： Lung internal contamination MPA-MURA Monte Carlo MLEM Spatial resolution detection efficiency

Measurement of the response function and the detection effciency of an organic liquid scintillator for neutrons between 1 and 30 MeV

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Chinese Physics C 2009年第8期33卷 677-681页

作者：黄翰雄阮锡超陈国长周祖英李霞鲍杰聂阳波仲启平 Department of Nuclear Physics China Institute of Atomic Energy

The light output function of a φ50.8 mm×50.8 mm BC501A scintillation detector was measured in the neutron energy region of 1 to 30 MeV by fitting the pulse height （PH） spectra for neutrons with the simulations from the NRESP code at the edge range. Using the new light output function, the neutron detection effciency was determined with two Monte-Carlo codes, NEFF and SCINFUL. The calculated effciency was corrected by comparing the simulated PH spectra with the measured ones. The determined effciency was verified at the near threshold region and normalized with a Proton-Recoil-Telescope （PRT） at the 8-14 MeV energy region.

关键词： liquid scintillator response function detection efficiency Monte-Carlo TOF

Latest developments in room-temperature semiconductor neutron detectors: Prospects and challenges

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Science China(Physics,Mechanics & Astronomy) 2023年第3期66卷 11-31页

作者： Linyue Liu Xiao Ouyang Runlong Gao Pengying Wan Xiaoping Ouyang State Key Laboratory of Intense Pulsed Radiation Simulation and Effect Northwest Institute of Nuclear TechnologyXi’an 710024China Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China School of Microelectronics Xi’an Jiaotong UniversityXi’an 710049China

Semiconductor-based neutron-detectors are characterized by small size, high energy-resolution, good spatial resolution, and stable response(at the depletion voltage). Consequently, these neutron-detectors are important for the fields of nuclear proliferation prevention, oil exploration, monitoring neutron-scattering experiments, cancer treatments, and space radiation effect research. However, there are some well-known problems for conventional silicon-based neutron detectors: low neutron-detection efficiency and limited resistance to radiation. Therefore, critical improvements are needed to enable sufficiently effective and practical neutron detection. To address these problems, direct-conversion neutron detectors as well as wide bandgap semiconductor-based detectors have been developed and studied intensely during the past years. Significant progress with respect to detection efficiency, radiation resistance, and room temperature operation was achieved. This paper reviews the latest research highlights, remaining challenges, and emerging technologies of direct-conversion neutron detectors as well as wide-bandgap semiconductor neutron detectors. This compact review serves as a reference for researchers interested in the design and development of improved neutron detectors in the future.

关键词： fusion reaction neutron convertor neutron detectors wide bandgap semiconductor detection efficiency radiation resistance

A normal-pressure MWPC for beam diagnostics at RIBLL2

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Chinese Physics C 2013年第6期37卷 59-62页

作者：唐述文马朋段利敏孙志宇鲁辰桂杨贺润胡荣江黄文学徐瑚珊 Institute of Modern Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

A normal pressure MWPC for beam diagnostics at RIBLL2 has been developed, wmcn has a sensluve area of 80 mm×80 mm and consists of three-layer wire planes. The anode plane is designed with a wider frame to reduce the discharge and without using protection wires. The detector has been tested with a 55Fe X-ray source and a 200 MeV/u ^12C beam from CSRm. A position resdution better than 250 μm along the anode wires and a detection efficiency higher than 90% have been achieved.

关键词： MWPC beam diagnostics delay line readout position resolution detection efficiency

Test and simulation of a MICROMEGAS detector

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Chinese Physics C 2011年第11期35卷 1033-1036页

作者：鲁辰桂段利敏徐瑚珊杨贺润胡荣江张金霞李祖玉 Institute of Modern Physics Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences

We report on the recent test results of a MICROMEGAS detector in terms of position resolution, time resolution and efficiency. With a Ar＋CO2 （10%） gas mixture and a strip pitch of 200 μm an accuracy of 80 μm in sigma on the position has been measured. The time resolution is better than 20 ns and a cosmic ray detection efficiency of 94% was obtained. A Monte Carlo simulation indicates that transverse diffusion, gain fluctuation and electronic noise limit the position resolution.

关键词： position resolution time resolution detection efficiency Monte Carlo simulation