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Nuclear Science and Techniques 2023年第2期34卷 178-189页

作者： Min Li Zhi‑Min Wang Cai‑Mei Liu Pei‑Zhi Lu Guang Luo Yuen‑Keung Hor Jin‑chang Liu chang‑gen yang Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China Sun Yat-sen University Guangzhou 510275China

This study presents the design and performance results for compact plastic scintillator strips using a wavelength shifting fiber(WLS-fiber)readout with dimensions of 0.1 m×0.02 m×2 *** approach was evaluated as a candidate for a cosmic-ray muon detector for the Taishan Antineutrino Observatory(JUNO-TAO).The strips coupled with 3-inch photomultiplier tubes(PMTs)were measured and compared between the single-end and double-end readout ***,a strip using the double-end option coupling with a silicon photomultiplier(SiPM)was further evaluated and compared with the results obtained using *** performance of the strips was determined by a detailed survey along their length with a cosmicray muon after detailed characterization of the 3-inch PMTs and *** proposed design employing a compact plastic scintillator strip with WLS-fiber coupling to a SiPM provides a good choice for cosmic-ray muon veto detectors,particularly when detector dimensions must be limited.

关键词： PMT SiPM Plastic scintillator WLS-fiber Muon detection Efficiency

Consistency test of PMT SPE spectrum from dark-noise pulses and LED low-intensity light

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Radiation Detection Technology and Methods 2018年第1期2卷 76-79页

作者： Yu-ting Wei Meng-yun Guan Wei-xing Xiong You-yu Gan chang-gen yang Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of ScienceBeijingChina School of Physics University of Chinese Academy of ScienceBeijingChina

Photomultiplier tube(PMT)has been an essential instrument for low background experiments,and the accuracy of single photoelectron(SPE)calibration will directly affect the energy reconstruction of the *** SPE spectrum can be acquired from the charge distribution of dark-noise pulses or the low-intensity light signal triggered by ***,there are arguments on whether the two methods are *** this paper,the Hamamatsu R5912-20mod PMT and the EMID642KNFL PMT have been tested adopting the two methods with signal waveform recording *** comparison,traditional charge-to-digital conversion system is also used to test SPE *** results show that they are consistent when the PMTs are working at typical recommended high voltage(HV).

关键词： PMT SPE Dark noise LED Waveform

Study on relative collection efficiency of PMTs with spotlight

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Radiation Detection Technology and Methods 2019年第3期3卷 30-36页

作者： Hai‑qiong Zhang Zhi‑min Wang Feng‑jiao Luo An‑bo yang Zhong‑Hua Qin chang‑gen yang Yue‑kun Heng University of Chinese Academy of Science Beijing 100049China Institute of High Energy Physics Beijing 100049China State Key Laboratory of Particle Detection and Electronics Beijing 100049China Key Laboratory of Particle Astrophysics Beijing 100049China

nd Photon detection efficiency is a key parameter of PMTs in high-precision neutrino and dark matter experiments,while normally the quantum efficiency is used with a normalization factor and angular response as the detection efficiency,where it is always coupled with detector response from the calibration ***,the absolute photon detection efficiency of 20′′PMTs in photon-counting level is further considered rather than the combination of quantum efficiency and normalization *** and method In order to have a good understanding of photon detection efficiency of the large-area PMT,we conduct a detailed comparison of relative collection efficiencies of a series of PMTs with *** study is based on the tests of relative quantum efficiency and relative detection efficiency,checked with several light *** All the results are consistent in relative QE and DE measurement with different light intensities,and the error of each parameter is coupled in our *** on the measurements,Hamamatsu R12860 shows the maximum collection efficiency with spotlight at PMT center,and Hamamatsu R12199,R1355 and HZC XP72B22 have the same level of CE within the *** Following the configuration on incident light and DE definition,we can further define the DE of a large-area PMT with similar algorithms,which will also be used for detector simulation in JUNO.

关键词： PMT QE Relative DE Relative CE

Preliminary measurement of the spherical proportional counter prototype

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Radiation Detection Technology and Methods 2018年第1期2卷 122-127页

作者： Zhi-Min Wang Charling Tao chang-Jiang Dai Hai-Qiong Zhang Peng Zhang Ning Zhou Yi Tao Chen-yang Tang Rui-Guang Wang chang-gen yang Ruo-qing Liu Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Tsinghua University Beijing 100084China Marseille Particle Physics Center(CPPM) 13233 MaseillesFrance University of Chinese Academy of Science BeijingChina

Introduction A novel large-volume spherical proportional counter(SPC)aims at relatively large target masses with low threshold,low background,and possible particle identification,with an extremely simple and robust *** In this paper,we present some progress on the study of such a kind of detector,with a prototype in Beijing for alpha neutron measurement and long-term running *** Preliminary understanding was achieved with a SPC *** can measure alpha and neutron and show the capability of particle ***-term running of the detector shows that it is a good stable *** It needs more tests and studies to reach lower energy region,better particle identification,more understanding of efficiency,*** The SPC,in principle,is capable of detecting very low energy nuclear recoils(in the few tens keV energy region)and smaller energy with lower pressure,thus being a very good candidate for rare event searches.

关键词： Gas detector SPC Alpha Neutron PSD

Prospects of detecting the reactor v_(e)-Ar coherent elastic scattering with a low-threshold dual-phase argon time projection chamber at Taishan

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Radiation Detection Technology and Methods 2021年第2期5卷 297-306页

作者： Yu-Ting Wei Meng-Yun Guan Jin-chang Liu Ze-Yuan Yu chang-gen yang Cong Guo Wei-Xing Xiong You-Yu Gan Qin Zhao Jia-Jun Li Institute of High Energy Physics CASBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China North China Electric Power University Beijing 100096China

Background We propose to measure the coherent elastic neutrino-nucleus scattering(CEvNS)using a dual-phase liquid argon time projection chamber(TPC)with 200 kg fiducial *** detector is expected to be adjacent to the JUNOTAO experiment and to be about 35 m from a reactor core with 4.6 GW thermal power at *** antineutrino flux is approximately 6×10^(12)cm^(−1)s^(−1) at this location,leading to more than 11,000 coherent scattering events per day in the fiducial *** The nuclear recoil energies concentrate in the sub-keV region,corresponding to less than ten ionization electrons in the liquid *** key question is how to veto and shield the background in the hall where the vertical overburden is about 5 *** what is the signal count rate and the background *** addition,what physical parameters can be measured what is the *** We used the Geant4 to simulate the backgrounds from cosmic ray muons and ambient radioactivity *** a veto and shielding design is *** a χ^(2) function is constructed and the sensitivity calculate package built to calculate the sensitivity of physical *** The detection of several ionization electrons can be achieved in the dual-phase TPC due to the large amplification in the gas *** a feasible detection threshold of four ionization electrons,the signal rate is 955 per *** detector is designed to be shielded well from cosmogenic backgrounds and ambient radioactivities to reach a 16%background-tosignal ratio in the energy region of *** the large CEvNS sample,the expected sensitivity of measuring the weak mixing angle sin^(2)θ_(w),and of limiting the neutrino magnetic moment are *** addition,a synergy between the reactor antineutrino CEvNS experiment and the dark matter experiment is foreseen.

关键词： Coherent elastic neutrino-nucleus scattering Dual-phase argon TPC Reactor antineutrinos

Calibration of liquid argon detector with ^(83m)Kr and ^(22)Na in different drift fields

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Radiation Detection Technology and Methods 2020年第2期4卷 147-152页

作者： Wei-Xing Xiong Meng-Yun Guan chang-gen yang Peng Zhang Jin-chang Liu Cong Guo Yu-Ting Wei You-Yu Gan Qing Zhao Jia-Jun Li Institute of High Energy Physics Beijing 100049China University of Chinese Academy of Sciences Beijing 100049China North China Electric Power University Beijing 100096China

Introduction Liquid noble gases are widely used as targets in low background search experiments,particularly in direct dark matter search experiments.83mKr is an excellent low-energy internal calibration source for future larger liquid noble gas *** To calibrate liquid argon detector with 83mKr in different drift fields and to study the correlation between light yield and drift *** A dual-phase LAr prototype detector was designed to study the 83mKr responses in liquid argon.83mKr atoms are produced through the decay of 83Rb and introduced into the LAr detector through the circulating purification *** We report that the light yield reaches 7.26±0.02 pe/keV for 41.5 keV from 83mKr and 7.66±0.01 pe/keV for 511 keV from 22Na,as a *** stopping the fill,the rate decays of 83mKr are with a fitted half-life of 1.83±0.11 h,which is consistent with the reported value of 1.83±0.02 *** light yield that varies with the drift electric field from 0 to 200 V/cm has also been reported.

关键词： Time projection chamber Noble liquid detectors Light yield Liquid argon

Inverse-time Backup Protection Based on Unified Characteristic Equation for Distribution Networks with High Proportion of Distributed generations

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 202-212页

作者： Nana chang Guobing Song Zhongxue chang Yuping Zheng Xingang yang the School of Electrical Engineering Xi’an Jiaotong UniversityXi’anChina State Key Laboratory of Smart Grid Protection and Control NARI Group CorporationNanjingChina Electric Power Research Institute of State Grid Shanghai Electric Power Company ShanghaiChina

The setting work of backup protection using steady-state current is tedious,and mismatches occasionally occur due to the increased proportion of distributed generations(DGs)connected to the power ***,there is a practical need to study a backup protection technology that does not require step-by-step setting and can be adaptively *** paper proposes an action sequence adaptive to fault positions that uses only positive sequence fault component(PSFC)*** the influence of DGs,the unified time dial setting can be obtained by selecting specific *** protection performance is improved by using the adjacent upstream and downstream protections to meet the coordination time interval in the case of metallic faults at the near-and far-ends of the ***,the expression and implementation scheme for inverse-time backup protection(ITBP)based on the unified characteristic equation is *** results show that this scheme can adapt to DG penetration scenarios and can realize the adaptive coordination of multi-level relays.

关键词： Inverse-time backup protection(ITBP) distributed generation(DG) positive sequence fault component(PSFC)voltage unified characteristic equation adaptive coordination

Significant contribution of carbonyls to atmospheric oxidation capacity(AOC)during the winter haze pollution over North China Plain

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Journal of Environmental Sciences 2024年第5期139卷 377-388页

作者： Xue yang gen Zhang Guang Pan Guolan Fan Houyong Zhang Xuan Ge Mingyue Du School of Municipal and Environmental Engineering Shandong Jianzhu UniversityJi’nan 250101China State Key Laboratory of Severe Weather&Key Laboratory of Atmospheric Chemistry of China Meteorological Administration Chinese Academy of Meteorological SciencesBeijing 100081China Shandong Jinan Ecological Environment Monitoring Center Ji’nan 250101China

Atmospheric carbonyl compounds play significant roles in the cycling of radicals and have exhibited surprisingly high levels in winter that were well correlated to particulate matter,for which the reason have not been clearly *** we measured carbonyl compounds and other trace gasses together with PM_(2.5)over urban Jinan in North China Plain during the *** higher carbonyl concentrations(average:14.63±4.21 ppbv)were found during wintertime haze pollution,about one to three-times relative to those on nonhaze days,with slight difference in chemical composition except formaldehyde(HCHO).HCHO(3.68 ppbv),acetone(3.17 ppbv),and acetaldehyde(CH_3CHO)(2.83 ppbv)were the three most abundant species,accounting for~75% of the total carbonylson both haze and non-haze *** from observational-based model(OBM)with atmospheric oxidation capacity(AOC)indicated that AOC significantly increased with the increasing carbonyls during the winter haze *** photolysis have supplied key oxidants such as RO_(2) and HO_(2),and thereby enhancing the formation of fine particles and secondary organic aerosols,elucidating the observed haze-carbonyls *** variation with carbonyls exhibiting peak values at early-noon and night highlighted the combined contribution of both secondary formation and primary diesel-fuel sources.1-butene was further confirmed to be the major precursor for *** study confirms the great contribution of carbonyls to AOC,and also suggests that reducing the emissions of carbonyls would be an effective way to mitigate haze pollution in urban area of the NCP region.

关键词： Carbonyls Haze Observation-based model Source apportionment Atmospheric oxidation capacity

Possibilities for the synthesis of superheavy element Z=121 in fusion reactions

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Nuclear Science and Techniques 2024年第6期35卷 90-100页

作者： Ming-Hao Zhang Yu-Hai Zhang Ying Zou Xiu-Xiu yang gen Zhang Feng-Shou Zhang The Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China School of Physical Science and Technology Guangxi UniversityNanning 530004China National Laboratory of Heavy Ion Accelerator of Lanzhou Center of Theoretical Nuclear PhysicsLanzhou 730000China

Based on the dinuclear system model,the calculated evaporation residue cross sections matched well with the current experimental *** synthesis of superheavy elements Z=121 was systematically studied through combinations of stable projectiles with Z=21-30 and targets with half-lives exceeding 50 *** influence of mass asymmetry and isotopic dependence on the projectile and target nuclei was investigated in *** reactions^(254)Es(^(46)Ti,3n)^(297)121 and^(252)Es(^(46)Ti,3n)^(295)121 were found to be experimentally feasible for synthesizing superheavy element Z=121,with maximal evaporation residue cross sections of 6.619 and 4.123 fb at 219.9 and 223.9 MeV,respectively.

关键词： Superheavy nuclei Dinuclear system model Fusion reaction Evaporation residue cross section

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Laser Powder Bed Fusion of Beta-Type Titanium Alloys for Biomedical Application:A Review

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 17-28页

作者： Xuan Luo Chao yang Dongdong Li Lai-chang Zhang State Key Laboratory of Materials Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan430074China National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials Guangdong Provincial Key Laboratory for Processing and Forming of Advanced Metallic MaterialsSouth China University of TechnologyGuangzhou510640China Centre for Advanced Materials and Manufacturing School of EngineeringEdith Cowan University270 Joondalup DriveJoondalupPerthWA6027Australia

Additive manufacturing ofβ-type titanium alloy is expected to replace Ti-6Al-4V alloy in the field of orthopedic implantation because of their low elastic modulus,excellent corrosion resistance,and *** briefly introducing the laser powder bed fusion(LPBF)process and physical phenomena,this paper reviews the recent progresses in LPBF-edβ-type Ti *** strategies to strengthening and tougheningβ-type Ti alloys are critically *** is followed by the processing routes employed to achieve to low modulus for orthopedic applications,especially a new methodology for tailoring crystallographic orientation called multi-track coupled directional *** effect of processing and compositions on performance metrics ofβ-type Ti alloys included corrosion behavior,and biocompatibility is *** the end,challenges in additive manufacturing ofβ-type Ti alloys in future are highlighted,with the aim to ensue clinical application of LPBF-edβ-type Ti alloys.

关键词： β-type Ti alloys Laser powder bed fusion Mechanical properties Elastic modulus Biocompatibility