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Compact lithium-glass neutron beam monitor for SANS at CSNS

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Nuclear Science and Techniques 2018年第9期29卷 165-170页

作者： Ke zhou jian-rong zhou Yu-Shou Song Xiao-Juan zhou Zhao-Yang Xie Gui-An Yang Yan-Feng Wang Yuan-Bo Chen Zhi-Jia Sun Fundamental Science on Nuclear Safety and Simulation Technology Laboratory Harbin Engineering UniversityHarbin 150001China Dongguan Neutron Science Center Dongguan 523803China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Particle Detection and Electronics Beijing 100049China

A small-angle scattering neutron spectrometer for material research is under construction at the China Spallation Neutron Source. An intervening neutron beam monitor behind the sample is needed to measure the beam intensity in order to reduce the measurement uncertainty caused by beam fluctuation. Considering the mobility requirement and limited space, we proposed a compact monitor using a type of lithium-glass scintillator provided by China Building Materials Academy. Its performance was studied experimentally using ^(252)Cf and ^(60)Co *** neutron light yield of the selected scintillator was measured to be 5:3 × 10~3 photons/neutron. The feasibility of n-gamma discrimination using the charge comparison method was verified. By using the Geant4 toolkit, themonitor was modeled with precise physical processes including neutron tracking, scintillation, and optical photon transmission. The gamma sensitivity and detection efficiency were investigated in the simulation. It was concluded that a 0.5-mm-thick lithium-glass scintillator with natural lithium is an appropriate choice to satisfy both the neutron detection efficiency and gamma elimination requirements.

关键词： Neutron beam monitor Lithium glass ngamma discrimination Detection efficiency

Simulation and optimization of the boron-lined MWPC neutron detectors

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Radiation Detection Technology and Methods 2021年第1期5卷 42-52页

作者： Lin Qiu Yang-dong Wei Xiao-hu Wang Bin Tang jian-rong zhou Zhi-jia Sun Fundamental Science on Nuclear Waste and Environmental Security Laboratory Southwest University of Science and TechnologyMianyang 621010China Institute of High Energy Physics China Academy of SciencesBeijing 100049China Spallation Neutron Source Science Center Dongguan 523000China State Key Laboratory of Particle Detection and Electronics Beijing 100049China

Purpose Boron-lined gas detectors are prospective alternatives to helium-3-based neutron *** boron-lined multiwire proportional chamber(MWPC)with neutron grazing incident angle geometry,high neutron detection efficiency and 3D position sensitive can be *** this paper,a multi-layer boron-lined MWPC was *** Influences of the boron coating thickness,coating layer numbers and neutron incident angle on the neutron detection efficiency were studied and optimized with Geant4 *** output signal properties including induced signal width on the readout plane,the time resolution and gas gain uniformity of the detector were studied with Garfield *** and conclusion The results show that the neutron detection efficiency can be significantly increased by using neutron grazing incident *** 4 layers of 10B4Cwith thickness of 1μm,the neutron detection efficiency can reach to 54.56%,49.17%and 44.36%when neutron incident angle is 6°,8°and 10°,*** detector with curved geometry,the gas gain is nonuniform among the anode wires,and using separate high voltage for each anode wire or wires group can effectively reduce the nonuniform of the gas *** results of this work can be used to optimize the detector design.

关键词： Neutron detector Boron-lined MWPC Simulation

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

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

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

Soil−water characteristics of weathered crust elution-deposited rare earth ores

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Transactions of Nonferrous Metals Society of China 2021年第5期31卷 1452-1464页

作者： Zhong-qun GUO jian-rong zhou Ke-fan zhou Jie-fang JIN Xiao-jun WANG Kui ZHAO School of Civil Engineering and Surveying&Mapping Engineering Jiangxi University of Science and TechnologyGanzhou 341000China jiangxi Key Laboratory of Mining Engineering Jiangxi University of Science and TechnologyGanzhou 341000China

The permeability of the weathered crust elution-deposited rare earth ores directly affects the efficiency of in-situ *** soil−water characteristic curve(SWCC)is an important constitutive relation for calculating the permeability of ore body,which is related to many ***−water characteristic tests of rare earth ore samples considering different factors were carried out by using the pressure plate *** of dry density,particle size and solution leaching on water holding behavior and the mechanism were *** experimental observations indicate that with the decrease of dry density,the pore ratio increases gradually,and the saturated water content *** the same matric suction,the water content decreases gradually with the increase of particle size,thus decreasing water holding capacity of ore *** the same water content,matric suction is inversely proportional to particle *** the same matric suction,the water content of ore samples after leaching is less than that of the ore samples before leaching,indicating that solution leaching can decrease water holding capacity of ore.

关键词： weathered crust elution-deposited rare earth ore dry density particle size solution leaching soil-water characteristic curve

STUDIES ON THE ASYMMETRIC DECOMPOSITION OF D,L-LEUCINE INDUCED BY ^(60)Co γ-IRRADIATION

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Chinese Chemical Letters 1993年第4期4卷 363-365页

作者： Wen Qing WANG jian jianG Yu rong zhou Ji Lan WU Department of Technical Physics,Peking University,Beijing 100871

Sublimed D-,L-,and DL-leucine under vacuum were subjected to ^(60)Co γ-irradiation with different *** enantiomeric compositions of samples were determined by chirasil- val capillary column gas chromatography,and the relative yields of radiolytic products(H_2, CO_2 and NH_3)were measured by packed column gas *** obtained data showed the peak area ratios D/L of DL-leucine after different absorbed doses of irradiation are all the same as that of samples with no irradiation,within the limit of *** are the ratios for the separately irradiated D-and *** suggests that no asymmetric decom- position was *** relative yields D/L of radiolytic products(H_2,CO_2 and NH_3)are very close to 1.00,indicating that the D-leucine cleavage rate was the same with that of the *** the view of dissipative structure,an explanation for the result was presented.

关键词： Co STUDIES ON THE ASYMMETRIC DECOMPOSITION OF D,L-LEUCINE INDUCED BY IRRADIATION

Effect of particle size and grain composition on two-dimensional infiltration process of weathered crust elution-deposited rare earth ores

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Transactions of Nonferrous Metals Society of China 2020年第6期30卷 1647-1661页

作者： Zhong-qun GUO Yuan-ming LAI Jie-fang JIN jian-rong zhou Kui ZHAO Zheng SUN School of Architectural and Surveying&Mapping Engineering Jiangxi University of Science and TechnologyGanzhou 341000China Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou 730000China jiangxi Key Laboratory of Mining Engineering Jiangxi University of Science and TechnologyGanzhou 341000China

The two-dimensional infiltration experiment was carried out by means of digital image *** evolution process of the wetting body was *** wetted front distance and the time show a very significant power function *** horizontal wetted distance is larger than the vertical wetted distance in the initial ***,the vertical distance of the wetted body gradually approaches to the horizontal *** infiltration distance decreases as the content of fine particles *** wetted front migration rate curve shows a three-stage change law,and it increases with the increase of coarse particle *** directional velocity ratio is *** initial value of horizontal infiltration rate is larger than that of vertical one,and then the vertical infiltration rate is gradually close to the horizontal *** empirical relationship between the characteristic particle size and the stable infiltration rate is established,which provides a theoretical basis for the prediction of the stable infiltration rate in in-situ leaching.

关键词： weathered crust elution-deposited rare earth ores particle size grain composition two-dimensional infiltration wetted front

Ergogenic Capacity of a 7-Chinese Traditional Medicine Extract in Aged Mice

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Chinese Medicine 2012年第4期3卷 223-228页

作者： jian-rong zhou Mohamed Aly M. Morsy Kiyoshi Kunika Kazumi Yokomizo Takeshi Miyata Department of Pharmacology Faculty of Medicine Minia University Minya Egypt Department of Presymptomatic Medical Pharmacology Faculty of Pharmaceutical Sciences Sojo University Kumamoto Japan Division of Science and Medicine Institute of International Kampo Co. Ltd. Nihonmatsu Japan

The ergogenic properties of a 7-Chinese traditional medicine water extract (Ligustrum lucidum ait, LLA), which is composed of the essences of Lycii fructus, Crataegi fructus, Phyllanthi fructus, Chrysanthemi flos, Coicis semen, Ganoderma lucidum, and Zizyphi fructus, were studied using aged mice. Mice were chronically (one month) administered LLA (0.1% and 1%) in the drinking water. Mice pre-treated with LLA showed a good appetite;however, they exhibited a lower rate of body weight increase compared to control mice. In mice subjected to the rotarod test, 1% LLA treatment provided effective adaption to fatigue and significantly increased the duration of mice on the rotarod. In locomotor activity test, 1% LLA potentiated mice mobility and significantly increased rearing behavior. In the antioxidant experiment, 1% LLA treatment significantly increased superoxide dismutase activity in the spleen and liver glutathione levels. These findings suggest that LLA may be utilized as an antifatigue agent, which may function through its antioxidant activity.

关键词： Antifatigue Antioxidant Chinese Traditional Medicine