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Electron irradiation effects on DC electrical performances of SiGe HBT in a comparison with Si BJT

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Rare Metals 2004年第4期23卷 330-339页

作者： mengxiangti ZHANGXimin WANGJilin HUANGWentiao CHENPeiyi KLAHongyong instituteofnuclearandNewenergytechnology TsinghuaUniversityBeijing100084China instituteofMicroelectronics TsinghuaUniversityBeijing100084China

The DC characteristics of SiGe HBT irradiated at different electron dose havebeen studied in a comparison with those of Si B JT. Generally, I_b and I_b - I_(b0) increase, I_c,I_c -I_(c0) and its +/- transition V_(be) as well as DC current gain ft decreases with increasingdose; increase of I_b -I_(b0) with increasing dose for Si BIT is much larger than that for SiGe HBT;beta increases with V_(be) or I_b, but decreases at I_b < 0.25 mA with I_b, and congregates athigher dose; and a damage factor d(beta) is much less at the same dose for SiGe HBT than for Si *** HBT has much better anti-radiation performance than Si BJT. Some anomalous phenomena forincrease of I_c, I_c -I_(c0), I_b -I_(b0) and beta at low dose have been found. Some electron trapshave been measured. The mechanism of changes of characteristics is discussed.

关键词： semiconductor technology SiGe HBT electron irradiation Si BJT DCelectrical performance

INFRARED ABSORPTION BANDS OF Si-H CENTERS IN γ-RAY IRRADIATED FZSi GROWN IN HYDROGEN ATMOSPHERE AND THEIR IDENTIFICATION

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Science in china,Ser.A 1987年第2期30卷 176-185页

作者：杜永昌张玉峰孟祥提沈宏扬 Department of Physics Peking university institute of nuclear energy technology Qinghua university institute of Atomic energy Academia Sinica beijing

Gamma-ray irradiated and neutron irradiated silicon have been stualea using the rourler transiorm inftared spectroscopy and deep-level transient spectroscopy. In γ-ray irradiated silicon the production rate of divacancy is very low, which can be used to identify radiation point defects. Only three new Si-H stretching vibration bands of 1832, 2054 and 1980 cm-1 are produced in γ-ray irradiated FZ （H）Si, fewer than that in neutron irradiated FZ（H）Si. In this paper the models of the three bands are discussed and their optical absorption sections are estimated.

关键词： RAY IRRADIATED FZSi GROWN IN HYDROGEN ATMOSPHERE AND THEIR IDENTIFICATION INFRARED ABSORPTION BANDS OF Si-H CENTERS IN Si

Milestone progress of the HEPS booster commissioning

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nuclear Science and Techniques 2024年第1期35卷 170-177页

作者： Yue-Mei Peng Jian-She Cao Jin-Hui Chen Hai-Yi Dong Ping He Yi Jiao Ling kang Wen kang Jian Li Jing-Yi Li Guo-Ping Lin Fang Liu Feng-Li Long Cai meng Xin Qi Hua-Min Qu Yan-Feng Sui Sheng Wang Gang Xu Qiang Ye Jing Zhang Pei Zhang Wei-Min Pan Key Laboratory of Particle Acceleration Physics and technology Institute of High Energy PhysicsChinese Academy of Sciences19B Yuquan RoadShijingshan DistrictBeijing 100049China university of the Chinese Academy of Sciences 19A Yuquan RoadShijingshan DistrictBeijing 100049China

The high-energy photon source(HEPS)is the first fourth-generation synchrotron light source facility in *** HEPS injector consists of a linear accelerator(Linac)and a full energy *** booster captures the electron beam from the Linac and increases its energy to the value required for the storage *** full-energy beam could be injected to the storage ring directly or after“high-energy accumulation.”On November 17,2023,the key booster parameters successfully reached their corresponding target *** milestone results were achieved based on numerous contributions,including nearly a decade of physical design,years of equipment development and installation,and months of beam *** measured at the extraction energy of 6 GeV,the averaged beam current and emittance reached 8.57 mA with 5 bunches and 30.37 nm rad with a single-bunch charge of 5.58 nC,compared with the corresponding target values of 6.6 mA and 35 nm rad,*** paper presents the physical design,equipment development,installation,and commissioning process of the HEPS booster.

关键词： High energy photon source Booster Beam commissioning

Normalized glandular dose coefficients for digital breast tomosynthesis using detailed Chinese breast models

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nuclear Science and Techniques 2024年第5期35卷 42-59页

作者： Jia-Hao Wang Rui Qiu An-kang Hu Ye-Qi Liu Zhen Wu Hui Zhang Jun-Li Li Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging Ministry of EducationTsinghua UniversityBeijing 100084China Joint institute of tsinghua university Nuctech Company Limited BeijingBeijing 100084China

The rise in breast cancer diagnoses among Chinese women has necessitated the use of X-ray breast screening,which carries a radiation *** study aimed to provide a dosimetry protocol for the Chinese female population to replace the traditional standard that utilizes simplified breast models,for the accurate estimation of the mean glandular dose of a patient undergoing digital breast tomosynthesis(DBT).The first set of detailed Chinese female breast models and representative breast parameters was *** backscatter radiation and computational efficiency,we improved the combination of these models and the Chinese reference adult female whole-body voxel *** acquisition for four commercial DBT systems that are widely employed in china was simulated using the Monte Carlo method to obtain the normalized glandular dose coefficients of DBT(D_(gN)^(DBT))and the glandular depth dose(D_(g)^(dep)(z))for different breast characteristics and X-ray *** calculated a series of D_(gN)^(DBT) values for breasts with different percentage mass glandularities(5%,25%,50%,75%,and 100%)and compressed breast thicknesses(2,3,4,5,6,and 7 cm)at various tube potentials(25,28,30,32,35,and 49 kV)and target/filter combinations(W/Rh,W/Al,Mo/Mo,Rh/Rh,and Rh/Ag).The parameter dependence of the breast characteristics and beam conditions on D_(gN)^(DBT) in detailed breast models was *** D_(gN)^(DBT) results were 14.6-51.0%lower than those of the traditional dosimetry standard in *** difference in D_(gN)^(DBT) was mainly due to a decrease in the depth of the main energy deposition area caused by the glandular distribution along the depth *** results obtained in this study may be used to improve breast dosimetry in china and provide more detailed information on risk assessment during DBT.

关键词： Digital breast tomosynthesis Normalized glandular dose coefficients Detailed breast model Monte Carlo simulation

Study on the optimal incident proton energy of ^(7)Li(p,n)^(7)Be neutron source for boron neutron capture therapy

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nuclear Science and Techniques 2024年第3期35卷 170-180页

作者： Yi-Nan Zhu Zuo-kang Lin Hai-Yan Yu Ye Dai Zhi-Min Dai Xiao-Han Yu Shanghai institute of Applied Physics Chinese Academy of SciencesShanghai 201800China university of Chinese Academy of Science Beijing 100049China

Boron neutron capture therapy(BNCT)is recognized as a precise binary targeted radiotherapy technique that effectively eliminates tumors through the^(10)B(n,α)^(7)Li nuclear *** various neutron sources,accelerator-based sources have emerged as particularly promising for BNCT ***^(7)Li(p,n)^(7)Be reaction is highly regarded as a potential neutron source for BNCT,owing to its low threshold energy for the reaction,significant neutron yield,appropriate average neutron energy,and additional *** study utilized Monte Carlo simulations to model the physical interactions within a lithium target subjected to proton bombardment,including neutron moderation by an MgF_(2)moderator and subsequent BNCT dose analysis using a Snyder head *** study focused on calculating the yields of epithermal neutrons for various incident proton energies,finding an optimal energy at 2.7 ***,the Snyder head phantom was employed in dose simulations to validate the effectiveness of this specific incident energy when utilizing a^(7)Li(p,n)^(7)Be neutron source for BNCT purposes.

关键词： Boron neutron capture therapy ^(7)Li(p,n)7Be neutron source Incident proton energy Monte Carlo simulation

Germylene-Fe complexes caused by heterometallic coupling and investigation into the 3d-4p bonding

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Chinese Chemical Letters 2024年第3期35卷 304-307页

作者： Yingying Qin Yongmei kang Lei Zhang Jianping Sun Zhijing Zhang Jialei Xu Fanlong Zeng Anyang Li Wenyuan Wang Weiqun Shi Key Laboratory of Synthetic and Natural Functional Molecule of Ministry of Education College of Chemistry and Materials ScienceNorthwest UniversityXi'an 710127China Laboratory of nuclear energy Chemistry Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Shaanxi Coal and Chemical Industry Xi'an 710054China

The interpretation of heterometallic bonding nature is a basic work of inorganic *** means of intermetallic substitution of germylene anions with iron halide complexes CpFe(CO)_(2)I andβ-diketiminato Fe^Ⅱchloride,the ferrogermylene complexes 3a,3b and 4a were synthesized and structurally *** structural and IR characterizations show the presence of the Ge←Feπbackbonding in molecules 3a,3b and *** computational works on frontier molecular orbitals and their comparison of energy states confirmed thatσdonation andπbackbonding are both weak in these molecules,despite three complexes have longer Ge-Fe bonds,whose strength decreases slightly with the degressive electron density around Fe environment in a sequence from 3a,3b to 4a.

关键词： Metallic bonding Germylene Iron Crystal structure σbond πbackbond

CFD analysis of a CiADS fuel assembly during the steam generator tube rupture accident based on the LBEsteamEulerFoam

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nuclear Science and Techniques 2023年第10期34卷 136-147页

作者： Yun-Xiang Li Lu meng Song Li Zi-Nan Huang Di-Si Wang Bo Liu You-Peng Zhang Tian-Ji Peng Lu Zhang Xing-kang Su Wei Jiang institute of Modern Physics Fudan UniversityShanghai 200433China institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of nuclear Science and technology University of Chinese Academy of SciencesBeijing 100049China Advanced energy Science and technology Guangdong Laboratory Huizhou 516003China School of nuclear Science and technology Lanzhou UniversityLanzhou 730000China

Steam generator tube rupture(SGTR) accident is an important scenario needed to be considered in the safety analysis of lead-based fast reactors. When the steam generator tube breaks close to the main pump, water vapor will enter the reactor core, resulting in a two-phase flow of heavy liquid metal and water vapor in fuel assemblies. The thermal-hydraulic problems caused by the SGTR accident may seriously threaten reactor core's safety performance. In this paper, the open-source CFD calculation software OpenFOAM was used to encapsulate the improved Euler method into the self-developed solver LBEsteamEulerFoam. By changing different heating boundary conditions and inlet coolant types, the two-phase flow in the fuel assembly with different inlet gas content was simulated under various accident conditions. The calculation results show that the water vapor may accumulate in edge and corner channels. With the increase in inlet water vapor content, outlet coolant velocity increases gradually. When the inlet water vapor content is more than 15%, the outlet coolant temperature rises sharply with strong temperature fluctuation. When the inlet water vapor content is in the range of 5–20%, the upper part of the fuel assembly will gradually accumulate to form large bubbles. Compared with the VOF method, Euler method has higher computational efficiency. However, Euler method may cause an underestimation of the void fraction, so it still needs to be calibrated with future experimental data of the two-phase flow in fuel assembly.

关键词： Steam generator tube rupture CiADS CFD simulations Two-phase flow

Application of deep learning methods combined with physical background in wide field of view imaging atmospheric Cherenkov telescopes

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nuclear Science and Techniques 2024年第4期35卷 208-220页

作者： Ao-Yan Cheng Hao Cai Shi Chen Tian-Lu Chen Xiang Dong You-Liang Feng Qi Gao Quan-Bu Gou Yi-Qing Guo Hong-Bo Hu Ming-Ming kang Hai-Jin Li Chen Liu Mao-Yuan Liu Wei Liu Fang-Sheng Min Chu-Cheng Pan Bing-Qiang Qiao Xiang-Li Qian Hui-Ying Sun Yu-Chang Sun Ao-Bo Wang Xu Wang Zhen Wang Guang-Guang Xin Yu-Hua Yao Qiang Yuan Yi Zhang School of Physics and technology Wuhan UniversityWuhan 430072China School of Physics and Astronomy Yunnan UniversityKunming 650091China Ministry of Education The Key Laboratory of Cosmic Rays(Tibet University)Lhasa 850000China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China university of Chinese Academy of Sciences 19 A Yuquan RoadShijingshan DistrictBeijing 100049China College of Physics Sichuan UniversityChengdu 610064China School of Intelligent Engineering Shandong Management UniversityJinan 250357China Tsung‑Dao Lee institute Shanghai Jiao Tong UniversityShanghai 200240China Suzhou Aerospace Information Research institute Suzhou 215123China College of Physics Chongqing UniversityNo.55 Daxuecheng South RoadHigh‑tech DistrictChongqing 401331China Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210008China

The High Altitude Detection of Astronomical Radiation(HADAR)experiment,which was constructed in Tibet,china,combines the wide-angle advantages of traditional EAS array detectors with the high-sensitivity advantages of focused Cherenkov *** objective is to observe transient sources such as gamma-ray bursts and the counterparts of gravitational *** study aims to utilize the latest AI technology to enhance the sensitivity of HADAR *** datasets and models with distinctive creativity were constructed by incorporating the relevant physical theories for various *** models can determine the type,energy,and direction of the incident particles after careful *** obtained a background identification accuracy of 98.6%,a relative energy reconstruction error of 10.0%,and an angular resolution of 0.22°in a test dataset at 10 *** findings demonstrate the significant potential for enhancing the precision and dependability of detector data analysis in astrophysical *** using deep learning techniques,the HADAR experiment’s observational sensitivity to the Crab Nebula has surpassed that of MAGIC and *** energies below 0.5 TeV and remains competitive with conventional narrow-field Cherenkov telescopes at higher *** addition,our experiment offers a new approach for dealing with strongly connected,scattered data.

关键词： VHE gamma-ray astronomy HADAR Deep learning Convolutional neural networks

10B-doped MCP detector developed for neutron resonance imaging at Back-n white neutron source

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nuclear Science and Techniques 2024年第8期35卷 58-68页

作者： Qiang Li Li‑Jiao Wang Jing‑Yu Tang Xiang‑Biao Qiu Zhen Chen Mao‑Yuan Zhao Chang‑Jun Ning Kai Pan Wei Xu Tao Li Su‑Peng Lu Han Yi Rui‑Rui Fan Chang‑Qing Feng Rong Zhang Xiao‑Yang Sun Qi An Hao‑Fan Bai Jiang‑Bo Bai Jie Bao Ping Cao Qi‑Ping Chen Yong‑Hao Chen Zeng‑Qi Cui An‑Chuan Fan Fan‑Zhen Feng Min‑Hao Gu Chang‑Cai Han Zi‑Jie Han Guo‑Zhu He Yong‑Cheng He Yang Hong Yi‑Wei Hu Han‑Xiong Huang Wei Jiang Zhi‑Jie Jiang Zheng‑Yao Jin Ling kang Bo Li Gong Li Xiao Li Yang Li Jie Liu Rong Liu Shu‑Bin Liu Yi‑Na Liu Guang‑Yuan Luan Jie Ren Zhi‑Zhou Ren Xi‑Chao Ruan Zhao‑Hui Song kang Sun Zhi‑Xin Tan Sheng‑Da Tang Jin‑Cheng Wang Peng‑Cheng Wang Zhao‑Hui Wang Zhong‑Wei Wen Xiao‑Guang Wu Xuan Wu Cong Xia Yong‑Ji Yu Guo‑Hui Zhang Hang‑Chang Zhang Lin‑Hao Zhang Qi‑Wei Zhang Xian‑Peng Zhang Yu‑Liang Zhang Yue Zhang Zhi‑Yong Zhang Zhi‑Hao Zhou Ke‑Jun Zhu Chong Zou institute of High energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China State Key Laboratory of Particle Detection and Electronics Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Dongguan Songshan Lake Future School Dongguan 523808China School of nuclear Science and technology University of Science and Technology of ChinaHefei 230027China State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China North Night Vision Science and technology(Nanjing)Research institute Co.Ltd Nanjing 211106China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China State Key Laboratory of nuclear Physics and technology School of PhysicsPeking UniversityBeijing 100871China institute of Modern Physics Fudan UniversityShanghai 200433China Key Laboratory of nuclear Data China Institute of Atomic EnergyBeijing 102413China china Academy of Engineering Physics Institute of Nuclear Physics and ChemistryMianyang 621900China USTC archaeometry lab University of Science and Technology of ChinaHefei 230026China Northwest institute of nuclear technology Xi’an 710024China university of Chinese Academy of Sciences Beijing 100049China china Shipbuilding Trading Co. LtdBeijing 100044China

Neutron resonance imaging(NRI)has recently emerged as an appealing technique for neutron *** complexity surpasses that of conventional transmission imaging,as it requires a high demand for both a neutron source and ***,the progression of NRI technology has been sluggish since its inception in the 1980s,particularly considering the limited studies analyzing the neutron energy range above *** white neutron source(Back-n)at the china Spallation Neutron Source(CSNS)provides favorable beam conditions for the development of the NRI technique over a wide neutron energy range from eV to ***-sensitive microchannel plates(MCP)have emerged as a cutting-edge tool in the field of neutron detection owing to their high temporal and spatial resolutions,high detection efficiency,and low *** this study,we report the development of a 10B-doped MCP detector,along with its associated electronics,data processing system,and NRI experiments at the *** heavy elements such as gold,silver,tungsten,and indium can be easily identified in the transmission images by their characteristic resonance peaks in the 1–100 eV energy range;the more difficult medium-weight elements such as iron,copper,and aluminum with resonance peaks in the 1–100 keV energy range can also be *** particular,results in the neutron energy range of dozens of keV(Aluminum)are reported here for the first time.

关键词： Neutron resonance imaging 10B doped MCP detector White neutron source Sample nuclide identification