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Test of a ^(3)He neutron detector readout electronics prototype for CSNS multipurpose physics neutron diffractometer

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Radiation Detection Technology and Methods 2021年第2期5卷 200-206页

作者： Xiao-guang Wu Yu-bin Zhao Hong Luo Jian-rong Zhou Liang Xiao Xiao-juan Zhou bei-ju guan Xing-cheng Tian Lin Zhu Xing-fen Jiang Zhi-jia Sun State Key Laboratory of Particle Detection and Electronics Institute of High Energy PhysicsChinese Academy of Sciences(CAS)Beijing 100049China University of Chinese Academy of Sciences(UCAS) Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China

Background Large areas of 3He neutron detector array and corresponding readout electronics are used in the MPI built at China Spallation Neutron Source(CSNS)to measure the position and flight time of scattered neutrons,and MPI has a high requirement for the position resolution of 3He neutron detector.A 3He neutron detector readout electronics prototype composed of two front-end boards and one digital readout board is designed to meet the above *** Testing the whole readout electronics system before its mass production to ensure it can run correctly and fulfill the functional and performance *** The test of the readout electronics prototype is implemented in the laboratory,and a signal generator is used to generate electronic signals instead of actual neutron *** position resolution test of the readout electronics prototype with 3He tubes is carried out in the No.20 beamline measurement room of *** and Conclusion The functional and performance tests in the laboratory state that the readout electronics prototype can fulfill the readout *** typical value of charge resolution is 0.85 fC;the integral nonlinearity of charge is 0.094%in the input charge range from 100 to 800 *** position resolution test result of the prototype with 3He tubes is better than the design requirement of 10 mm and also quite good compared with that of some other commercial *** tests provide a reliable basis for the mass production of the readout electronics prototype.

关键词： CSNS MPI 3He tube Readout electronics prototype Functional and performance tests

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A large area ^(3)He tube array detector with vacuum operation capacity for the SANS instrument at the CSNS

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Nuclear Science and Techniques 2022年第7期33卷 83-92页

作者： Xing-Fen Jiang Jian-Rong Zhou Hong Luo Liang Xiao Xiao-juan Zhou Hong Xu Yuan-guang Xia Xiao-guang Wu Lin Zhu Wen-Qing Yang Gui-An Yang bei-ju guan Hong-Yu Zhang Yu-Bin Zhao Zhi-Jia Sun Yuan-Bo Chen State Key Laboratory of Particle Detection and Electronics Institute of High Energy PhysicsChinese Academy of SciencesBeijing100049China Spallation Neutron Source Science Center Dongguan523803China University of Chinese Academy of Sciences Beijing100049China

The small-angle neutron scattering(SANS)instrument,one of the first three instruments of the China Spallation Neutron Source(CSNS),is designed to probe the microscopic and mesoscopic structures of materials in the scale range 1–100 nm.A large-area ^(3)He tube array detector has been constructed and operates at the CSNS SANS instrument since August *** consists of 120 linear position-sensitive detector tubes,each 1 m in length and 8 mm in diameter,and filled with ^(3)He gas at 20 bar to obtain a high detection *** ^(3)He tubes were divided into ten modules,providing an overall area of 1000 mm×1020 mm with a high count rate *** each tube is installed independently,the detector can be quickly repaired in situ by replacing damaged *** reduce air scattering,the SANS detector must operate in a vacuum environment(0.1 mbar).An all-metal sealing technique was adopted to avoid high-voltage breakdown by ensuring a high-voltage connection and an electronic system working in an atmospheric environment.A position resolution of 7.8±0.1 mm(full width at maximum)is measured along the length of the tubes,with a high detection efficiency of 81±2% at *** over the past four years,the detector appears to perform well and with a high stability,which supports the SANS instrument to finish approximately 200 user scientific programs.

关键词： Neutron detectors ^(3)He tubes Gaseous detectors Small-angle neutron scattering

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Large area^(3)He tube array detector with modular design for multi‑physics instrument at CSNS

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Nuclear Science and Techniques 2023年第1期34卷 1-12页

作者： Lin Zhu Jian‑Rong Zhou Yuan‑guang Xia Liang Xiao Hong Luo Xiao‑juan Zhou Wen‑Qin Yang bei‑ju guan Xing‑Fen Jiang Yan‑Feng Wang Hong Xu Hai‑Yun Teng Li‑Xin Zeng Jia‑Jie Li Lei Hu Ke Zhou Yong‑Xiang Qiu Pei‑Xun Shen jun Xu Li‑Jiang Liao Xiao‑Zhuang Wang Gui‑An Yang Huai‑Chan Chen ju‑Ping Xu Zhi‑Duo Li Song‑Lin Wang Jian Zhuang Yu‑Bin Zhao jun‑Rong Zhang Wen Yin Zhi‑Jia Sun Yuan‑Bo Chen Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Spallation Neutron Source Science Center Dongguan 523803China University of Chinese Academy of Sciences Beijing 100049China

The multi-physics instrument(MPI)is the first user cooperative instrument at the China Spallation Neutron Source(CSNS).It was designed to explore the structures of complex materials at multiple scales based on the neutron total scattering *** imposes the requirements for the detector,including a high detection efficiency to reduce the measurement time and a large solid angle coverage to cover a wide range of momentum *** satisfy these demands,a large-area array of 3He-filled linear position-sensitive detectors(LPSDs)was constructed,each with a diameter of 1 inch and pressure of 20 *** uses an orbicular layout of the detector and an eight-pack module design for the arrangement of 3He LPSDs,covering a range of scattering angles from 3°to 170°with a total detector area of approximately 7 *** detector works in air,which is separated from the vacuum environment to facilitate installation and *** characteristics of the MPI detector were investigated through Monte Carlo(MC)simulations using Geant4 and experimental *** results suggest that the detectors are highly efficient in the wavelength range of the MPI,and an efficiency over 25%is achievable for above 0.1 A neutrons.A minimal position resolution of 6.4 mm full width at half maximum(FWHM)along the tube length was achieved at a working voltage of 2200 V,and a deviation below 2 mm between the real and measured positions was attained in the beam *** detector module exhibited good consistency and an excellent counting rate capacity of up to 80 kHz,which satisfied the requirements of experiments with a high event *** of its operation over the past year have shown that the detector works steadily in sample experiments,which allows the MPI to serve the user program successfully.

关键词： Neutron detector LPSD Position resolution Counting rate capacity

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Development of 3He-filled linear position-sensitive detector for neutron scattering instruments at CSNS

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Radiation Detection Technology and Methods 2023年第1期7卷 100-106页

作者： Lin Zhu Jian-rong Zhou Xin-feng Jiang Xiao-juan Zhou Wen-qin Yang Yuan-guang Xia Liang Xiao Hong Luo bei-ju guan Yan-feng Wang Hong Xu Pei-xun Shen Hai-yun Teng Jia-jie Li Gui-an Yang ju-ping Xu Huai-can Chen Song-lin Wang Jian Zhuang jun-rong Zhang Wen Yin Zhi-jia Sun Yuan-bo Chen Tianjiao Liang Institute of High Energy Physics Chinese Academy of SciencesBeijing100049China Spallation Neutron Source Science Center Dongguan523803GuangdongChina University of Chinese Academy of Sciences Beijing100049China

Background Helium-3-filled linear position-sensitive detectors(LPSDs)have been widely applied to neutron scattering instruments in recent decades owing to the high detection efficiency,the excellent neutron/gamma discrimination,and the ability to construct the detector with large area *** than 65%of neutron instruments at the China Spallation Neutron Source(CSNS)require ^(3)He LPSDs for the building of the detector *** detector of a neutron scattering instrument is normally an array detector composed of a large number of ^(3)He ***,no appropriate substitute detector is available for the ^(3)He LPSD for operation over a short period,and its specifications need to be customized to satisfy the requirements of different *** necessitates the development of ^(3)He LPSDs with different specifications for building and upgrading the detectors of neutron scattering instruments at *** To meet the general requirements specified by the neutron instruments at CSNS,a ^(3)He LPSD was developed and its performances were investigated by using the neutron *** The neutron beam experiments for this ^(3)He LPSD,including measurements of counting rate plateau curve,position calibration,and position resolution along the tube path,were carried out at the beamline-20 of *** evaluate its performance in the instrument operation,a detector module made of this ^(3)He LPSD has been installed in the multi-physics instrument(MPI),and the comparison test with the commercial ^(3)He LPSD has been conducted at neutron scattering *** and conclusion The experimental measurements for this ^(3)He LPSD based on the neutron beam showed that it satisfies the requirements for use in neutron scattering *** reaches a plateau slope of 2.6%/100 V with a plateau range from 1750 to 1950 V and attained a minimal position resolution of 5.3 mm(FWHM),superior to the one achieved by the commercial ^(3)He *** addition,this ^(3)He

关键词： Counting rate CSNS LPSD Plateau curve Position resolution

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Endoplasmic reticulum stress and autophagy in cerebral ischemia/reperfusion injury:PERK as a potential target for intervention

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Neural Regeneration Research 2025年第5期20卷 1455-1466页

作者： ju Zheng Yixin Li Ting Zhang Yanlin Fu Peiyan Long Xiao Gao Zhengwei Wang Zhizhong guan Xiaolan Qi Wei Hong Yan Xiao Key Laboratory of Endemic and Ethnic Diseases Ministry of Education&Key Laboratory of Medical Molecular Biology of Guizhou ProvinceGuizhou Medical UniversityGuiyangGuizhou ProvinceChina Guizhou Center for Disease Control and Prevention GuiyangGuizhou ProvinceChina Department of Histology and Embryology Guizhou Medical UniversityGuiyangGuizhou ProvinceChina Collaborative Innovation Center for Prevention and Control of Endemic and Ethnic Regional Diseases Co-constructed by the Province and Ministry GuiyangGuizhou ProvinceChina

Several studies have shown that activation of unfolded protein response and endoplasmic reticulum(ER)stress plays a crucial role in severe cerebral ischemia/reperfusion *** occurs within hours after cerebral ischemia,but the relationship between ER stress and autophagy remains *** this study,we established experimental models using oxygen-glucose deprivation/reoxygenation in PC12 cells and primary neurons to simulate cerebral ischemia/reperfusion *** found that prolongation of oxygen-glucose deprivation activated the ER stress pathway protein kinase-like endoplasmic reticulum kinase(PERK)/eukaryotic translation initiation factor 2 subunit alpha(e IF2α)-activating transcription factor 4(ATF4)-C/EBP homologous protein(CHOP),increased neuronal apoptosis,and induced ***,inhibition of ER stress using inhibitors or by si RNA knockdown of the PERK gene significantly attenuated excessive autophagy and neuronal apoptosis,indicating an interaction between autophagy and ER stress and suggesting PERK as an essential target for regulating *** autophagy with chloroquine exacerbated ER stress-induced apoptosis,indicating that normal levels of autophagy play a protective role in neuronal injury following cerebral ischemia/reperfusion *** from this study indicate that cerebral ischemia/reperfusion injury can trigger neuronal ER stress and promote autophagy,and suggest that PERK is a possible target for inhibiting excessive autophagy in cerebral ischemia/reperfusion injury.

关键词： apoptosis ATF4 autophagy C/EBP homologous protein cerebral ischemia/reperfusion injury eIF2α endoplasmic reticulum stress PERK

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Metal bioaccumulation in plant leaves from an industrious area and the Botanical Garden in beijing

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Journal of Environmental Sciences 2005年第2期17卷 294-300页

作者： LIUYan-ju DINGHui ZHUYong-guan beijingCentreforPhysicalandChemicalAnalysis Beijing100089China／／ResearchCenterforEco-EnvironmentalSciencesChineseAcademyofSciencesBeijing100085China beijingCentreforPhysicalandChemicalAnalysis Beijing100089China ResearchCenterforEco-EnvironmentalSciences ChineseAcademyofSciencesBeijing100085China

The concentrations of Fe, Mn, Al, Zn, Pb, Ni, Cr, and As were measured in soils and leaves from 21 plant species growing on hills near the beijing Steel Factory(BSF) and 17 plant species in the beijing Botanical Garden(BBG). The results showed that soils from BSF were Zn contaminated according to the threshold of natural background of China. There was a metal contamination of the soils by Ni, and Cr in BSF comparing with those in BBG. The comparison between concentrations of metals in leaves from both sites indicated that, in general, accumulation of metals in the leaves of the same species was significantly different between the two sites. Even within the same locality each species accumulation of metals was significantly variable. The study aimed to screen landscape plants for the capacity to clean-up toxic metals in soils, and developed an overall metal accumulation index(MAI) for leaves and then categorized the MAI that can be applied broadly in the selection of species in polluted areas. To do this, the spectrum of MAI values were divided into four classes: strongly accumulated(SA or grade I), moderately accumulated(MA or grade II), intermediately accumulated(IA or grade III), and weakly accumulated(WA or grade IV). The results showed that elemental association between Fe, Al, Ni, and As was generally highly correlated with each other in the sampling sites. This may suggest their common biochemical characteristics. Generally, those species containing strong and moderate accumulation in both sites are considered including Vitex negundo, Broussonetia papyrifera, Ulmus pumila, and Rubia cordifolia. At BSF and other industrial sites with a similar ecosystem, strong and moderate accumulation species include Sophora japonica, Ampelopsis aconitifolia var. glabra, Platycladus orientalis, Wikstroemia chamaedaphne, Cleistogenes squarrosa, Grewia biloba, and in BBG, in addition Setaria viridis, Cotinus coggygria, Lespedeza floribunda, Rhamnus parvifolia, Lespedeza tomento

关键词： Fe Mn Al Zn Pb Ni As metal accumulation index(MAI)

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Layered D2D NOMA

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China Communications 2021年第1期18卷 33-42页

作者： Jinjuan ju Jinyuan Gu guan Zhang School of Information Science and Technology Nantong UniversityNantong 226019China School of Electronic and Information Engineering Nantong Vocational UniversityNantong 226007China

This paper investigates a layered power allocation(PA)non-orthogonal multiple access(NOMA)scheme for device-to-device(D2D)relaying networks,where the strategy of partial data transmission at relay nodes are adopted to improve the efficiency of *** addition,to satisfy different quality-of-service(QoS)requirements from multiple users,layered and grouped manners are ***,the closed-form expressions in terms of the sum-rate(SR)and outage probability of the proposed scheme are derived for independent Rayleigh fading channels,which demonstrates our theoretical *** analytical and simulation results are provided to show the superiority of our proposed scheme compared with existing works.

关键词： non-orthogonal multiple access deviceto-device sum-rate outage probability

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Completeness of the system {z^(λ_n)}in L^2[B,α_0]

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Acta Mathematica Sinica,English Series 2008年第12期24卷 2101-2110页

作者： ju Hong NING guan Tie DENG Department of Mathematics Jiangxi Normal University Nanchang 330022 P. R. China School of Mathematical Sciences Beijing Normal University Beijing 100875 P. R. China

Let B be an unbounded domain located outside an angle domain with vertex at the origin, A ={λn}（n = 1,2,...） be a sequence of complex numbers satisfying sup ｜ arg（λn）｜〈 α 〈 π/2 and denote by M（∧） = {z^λ, λ ∈ ∧} the corresponding system of functions z^λ（λ∈∧）. Let α0（z） be a weight function defined on B. We obtain a completeness theorem for the system M（∧） in the Hilbert space L^2 [B, α0].

关键词： completeness unbounded domain Hilbert space

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Separation occurring during the drop weight tear test of thick-walled X80 pipeline steels

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International Journal of Minerals,Metallurgy and Materials 2013年第8期20卷 741-747页

作者： Qing-yun Sha Da-hang Li Guo-jian Huang ju guan Technology Center Anshan Iron and Steel Group Company

A separation phenomenon occurring during the drop weight tear test of commercial thick-walled API （American Petroleum Institute） X80 strip steel was investigated in this work. Microstructural analysis showed that the band structure of bainite elongated along the rolling direction works as the initiation sites of separation. The propagation of separation can be promoted not only by the occurrence of the band structure of martensite/austenite constituent, prior austenite grain boundaries, and elongated bainite, but also by fine acicular ferrite and bainite. Wide separation formed in the former case, while the narrow one appeared in the latter case. acicular ferrite in thick-walled X80 pipeline steel in order Some methods were proposed to obtain fine and homogeneous to minimize the occurrence of separation.

关键词： pipeline steel drop weight tear test separation cracking band structure

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On the Energy Transfer of a Colinear OH+O System

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Chemical Research in Chinese Universities 2001年第1期17卷 88-94页

作者： WU Tao CHEN Xian yang PENG Jian bo ju guan Zhi State Key Laboratory of Coordination Chemistry Coordination Chemistry InstituteDepartment of ChemistryNanjing UniversityNanjing 210093P.R.China State Key Laboratory of Crystal Material Shandong UniversityJinan 250100P.R.China

A quantum mechanical calculation was performed to study the Translation Vibration( T V ) energy transfer of a colinear OH+O/OD+O system, for which Delves coordinates and R matrix propagatation methods were applied to a Mulius Blint potential energy surface. The calculated result of the T V energy transfer probability shows strong oscillation phenomena and the collision delay time of the title system was in the 10 -15 -10 -12 s time scale. The kinetic isotope effect was discussed in this work too.

关键词： V T energy transfer Probability Lifetime Isotope effect

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