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In-beam gamma rays of CSNS Back-n characterized by black resonance filter

NUCLEAR SCIENCE AND TECHNIQUES 2024年第10期35卷 1-12页

作者： Wang, Jin-Cheng Ren, Jie Jiang, Wei Ruan, Xi-Chao Liu, Ying-Yi yang, hao-lan Xu, Kuo-Zhi Pan, Xin-Yi Sun, Qi Bao, Jie Huang, Han-Xiong Bai, hao-Fan Bai, Jiang-Bo Cao, Ping Chen, Qi-Ping Chen, Yong-hao Duan, Wen-hao Fan, An-Chuan Fan, Rui-Rui Feng, Chang-Qing Gu, Min-hao Han, Chang-Cai Han, Zi-Jie He, Guo-Zhu He, Yong-Cheng Hong, yang Hu, Yi-Wei Jiang, Zhi-Jie Kang, Ling lan, Chang-Lin Li, Bo Li, Feng Li, Qiang Li, Xiao Li, yang Liu, Jie Liu, Rong Liu, Shu-Bin Liu, Yi-Na Luan, Guang-Yuan Ning, Chang-Jun Qiu, Yi-Jia Ren, Wen-Kai Ren, Zhi-Zhou Song, Zhao-Hui Sun, Kang Tan, Zhi-Xin Tang, Jing-Yu Tang, Sheng-Da Wang, Li-Jiao Wang, Peng-Cheng Wang, Zhao-Hui Wen, Zhong-Wei Wu, Xiao-Guang Wu, Xuan Wu, Ze-Peng Xia, Cong Xie, Li-Kun Yi, Han Yu, Tao Yu, Yong-Ji Zhang, Guo-Hui Zhang, Hang-Chang Zhang, Qi-Wei Zhang, Xian-Peng Zhang, Yu-Liang Zhang, Zhi-Yong Zhao, Mao-Yuan Zhou, Zhi-hao Zhu, Ke-Jun Zou, Chong China Inst Atom Energy Key Lab Nucl Data Beijing 102413 Peoples R China Chinese Acad Sci Inst High Energy Phys Beijing 100049 Peoples R China Spallat Neutron Source Sci Ctr Dongguan 523803 Peoples R China Chinese Acad Sci Inst High Energy Phys State Key Lab Particle Detect & Elect Beijing 100049 Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China Peking Univ Sch Phys State Key Lab Nucl Phys & Technol Beijing 100871 Peoples R China Fudan Univ Inst Modern Phys Shanghai 200433 Peoples R China Univ Sci & Technol China State Key Lab Particle Detect & Elect Hefei 230026 Peoples R China Univ Sci & Technol China Sch Nucl Sci & Technol Hefei 230026 Peoples R China Univ Sci & Technol China Dept Modern Phys Hefei 230026 Peoples R China China Acad Engn Phys Inst Nucl Phys & Chem Mianyang 621900 Peoples R China Univ Sci & Technol China USTC Archaeometry Lab Hefei 230026 Peoples R China Northwest Inst Nucl Technol Xian 710024 Peoples R China lanzhou Univ Sch Nucl Sci & Technol Lanzhou 730000 Peoples R China Univ Sci & Technol China Inst Adv Technol Hefei 230027 Peoples R China

The back-streaming white-neutron beamline (Back-n) of the China Spallation Neutron Source is an essential neutron- research platform built for the study of nuclear data, neutron physics, and neutron applications. Many types of cross-sectional neutron-reaction measurements have been performed at Back-n since early 2018. These measurements have shown that a significant number of gamma rays can be transmitted to the experimental stations of Back-n along with the neutron beam. These gamma rays, commonly referred to as in-beam gamma rays, can induce a non-negligible experimental background in neutron-reaction measurements. Studying the characteristics of in-beam gamma rays is important for understanding the experimental background. However, measuring in-beam gamma rays is challenging because most gamma-ray detectors are sensitive to neutrons; thus, discriminating between neutron-induced signals and those from in-beam gamma rays is difficult. In this study, we propose the use of the black resonance filter method and a CeBr3 scintillation detector to measure the characteristics of the in-beam gamma rays of Back-n. Four types of black resonance filters, Ta-181, Co-59, Ag-nat, and Cd-nat, were used in this measurement. The time-of-flight (TOF) technique was used to select the detector signals remaining in the absorption region of the TOF spectra, which were mainly induced by in-beam gamma rays. The energy distribution and flux of the in-beam gamma rays of Back-n were determined by analyzing the deposited energy spectra of the CeBr3 scintillation detector and using Monte Carlo simulations. Based on the results of this study, the background contributions from in-beam gamma rays in neutron-reaction measurements at Back-n can be reasonably evaluated, which is beneficial for enhancing both the experimental methodology and data analysis.

关键词： In-beam gamma rays Back-n Black filter resonance technique In-beam gamma rays Back-n CeBr3 scintillator Black filter resonance technique C6D6 DETECTOR SYSTEM LINE

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Rapid interrogation of special nuclear materials by combining scattering and transmission nuclear resonance fluorescence spectroscopy

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Nuclear Science and Techniques 2021年第8期32卷 67-77页

作者： hao-yang lan Tan Song Jia-Lin Zhang Jian-Liang Zhou Wen Luo School of Nuclear Science and Technology University of South ChinaHengyang 421001China National Exemplary Base for International Sci.&Tech. Collaboration of Nuclear Energy and Nuclear SafetyUniversity of South ChinaHengyang 421001China

The smuggling of special nuclear materials(SNMs)across national borders is becoming a serious threat to nuclear *** paper presents a feasibility study on the rapid interrogation of concealed SNMs by combining scattering and transmission nuclear resonance fluorescence(s NRF and t NRF)*** s NRF spectroscopy,SNMs such as^(235,238)U are excited by a wide-band photon beam of appropriate energy and exhibit unique NRF *** Carlo simulations show that one-dimensional scans can realize isotopic identification of concealed^(235,238)U when the detector array used for interrogation has sufficiently high energy *** simulated isotopic ratio^(235U/238)U is in good agreement with the theoretical value when the SNMs are enclosed in relatively thin *** interrogation is followed by t NRF spectroscopy using a narrow-band photon beam with the goal of obtaining tomographic images of the concealed *** reconstructed image clearly reveals the position of the isotope^(235)U inside an iron *** is shown that the interrogation time of s NRF and t NRF spectroscopy is one order of magnitude lower than that when only t NRF spectroscopy is used and results in a missed-detection rate of 10^(-3).The proposed method can also be applied for isotopic imaging of other SNMs such as^(239,240)Pu and^(237)Np.

关键词： Special nuclear material Nondestructive interrogation Nuclear resonance fluorescence

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小地老虎硫氧还蛋白过氧化物酶AiTPX1的分子特征及其对杀虫剂胁迫的响应

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应用昆虫学报 2024年第2期61卷 258-270页

作者：杨浩岚赵乐曹付江连强刘苏李茂业李世广安徽农业大学植物保护学院作物有害生物综合治理安徽省重点实验室四川省烟草公司凉山州公司

【目的】硫氧还蛋白过氧化物酶（TPX）在昆虫抵御氧化胁迫中具有重要作用。本研究旨在鉴定小地老虎Agrotis ipsilon TPX基因，明确其编码蛋白质的抗氧化能力，阐明TPX基因在小地老虎不同发育期、不同组织以及在3种杀虫剂（高效氯氟氰菊... 详细信息

【目的】硫氧还蛋白过氧化物酶（TPX）在昆虫抵御氧化胁迫中具有重要作用。本研究旨在鉴定小地老虎Agrotis ipsilon TPX基因，明确其编码蛋白质的抗氧化能力，阐明TPX基因在小地老虎不同发育期、不同组织以及在3种杀虫剂（高效氯氟氰菊酯、辛硫磷和氯虫苯甲酰胺）胁迫下的表达模式，为深入了解小地老虎TPX基因的生理功能奠定基础。【方法】利用同源检索技术从小地老虎转录组中鉴定TPX基因，利用大肠杆菌表达重组蛋白并分析其抗氧化能力，使用实时荧光定量PCR技术分析TPX基因的表达模式，使用试剂盒检测幼虫体内H2O2的含量变化。【结果】从小地老虎转录组中鉴定了1个TPX基因的cDNA序列，命名为AiTPX1。根据其编码蛋白质的结构特征，结合系统进化分析结果，确定AiTPX1属于2-Cys家族。在大肠杆菌中成功表达了AiTPX1重组蛋白，该蛋白能够显著提高大肠杆菌在氧化胁迫下的存活率（P<0.05）。AiTPX1基因在小地老虎不同发育期和不同组织中均有表达，但在蛹期和幼虫中肠中表达量最高。使用LC50剂量的高效氯氟氰菊酯、辛硫磷和氯虫苯甲酰胺处理小地老虎幼虫后，幼虫体内H2O2含量显著升高，AiTPX1表达水平也显著上升。高效氯氟氰菊酯处理后24 h,AiTPX1表达水平为对照组的8.1倍（P<0.05），辛硫磷和氯虫苯甲酰胺处理后6 h,AiTPX1转录水平分别为对照组的6.5倍和6.0倍（P<0.05）。【结论】AiTPX1可能具有缓解高效氯氟氰菊酯、辛硫磷和氯虫苯甲酰胺引起的氧化胁迫的功能，从而增强小地老虎幼虫对3种杀虫剂的耐受性。

关键词：小地老虎硫氧还蛋白过氧化物酶原核表达杀虫剂氧化胁迫表达模式

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基于前离子选择的UHPLC-Q-TOF-MS/MS技术快速筛查加味定志丸中的化学成分

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药学学报 2024年第8期59卷 2350-2364页

作者：魏祖英方聪陈奎杨浩澜刘洁贾志鑫李月婷肖红斌北京中医药大学中药学院北京100029 北京中医药大学中药分析与转化研究中心北京100029 江西中医药大学江西南昌330000 北京中医药大学北京中医药研究院北京100029

本研究建立一种基于前离子选择(precursor ion selection,PIS)采集策略的超高效液相色谱-四极杆-飞行时间质谱(UHPLC-Q-TOF-MS)分析方法,全面快速筛查加味定志丸(Jiawei Dingzhi pills,JWDZP)中成分。利用在线数据库和文献统计复方药味... 详细信息

本研究建立一种基于前离子选择(precursor ion selection,PIS)采集策略的超高效液相色谱-四极杆-飞行时间质谱(UHPLC-Q-TOF-MS)分析方法,全面快速筛查加味定志丸(Jiawei Dingzhi pills,JWDZP)中成分。利用在线数据库和文献统计复方药味的化学成分,共计1 921个,经来源互证、统一成分名称、合并多药味归属成分、去掉弱极性分子后,构建了包含450个成分的JWDZP化学成分数据库。采用Acquity UPLC HSS T3柱(100 mm×2.1 mm,1.8μm),以0.1%甲酸水(A)-乙腈(B)为流动相,流速0.35 mL·min^(-1),柱温35℃,电喷雾离子源,在正、负离子模式下基于PIS采集策略采集质谱数据,通过精确分子量匹配筛查数据库中的化学成分,利用其特征碎片离子、中性丢失、文献质谱数据比对进行结构确认,部分化合物利用对照品进行确认。共从JWDZP提取物中筛查到176个化合物,其中26个化合物经过对照品比对确认。这些化合物包含君药成分96个,共流出离子强度低成分34个。本研究建立的PIS-UHPLC-Q-TOF-MS/MS方法能快速全面筛查JWDZP中的化学成分,增强对共流出离子强度低成分的筛查,为JWDZP物质基础研究提供依据。

关键词：加味定志丸 UHPLC-Q-TOF-MS/MS 化学成分前离子选择采集结构鉴定

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Model for estimating the weight-loss ratio of damaged Korla fragrant pears

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 261-266页

作者： yang Liu Yurong Tang Hong Zhang hao Niu Haipeng lan College of Mechanical and Electrical Engineering Tarim UniversityAlaer 843300XinjiangChina College of Water Resources and Architectural Engineering Tarim UniversityAlaer 843300XinjiangChina

To predict the weight-loss ratio of Korla fragrant pears effectively,improve commodity value and study the variation laws of the weight-loss ratio of damaged fragrant pears during storage,this study predicted the weight-loss ratio of fragrant pears by utilizing the generalized regression neural network(GRNN),support vector regression(SVR),partial least squares regression(PLSR)and error back propagation neural network(BPNN).The prediction performances of GRNN,SVR,PLSR and BPNN models were compared comprehensively,and the optimal model was *** addition,the optimal prediction model was *** results show that weight-loss ratio of fragrant pears increases gradually with the extension of storage *** storage,the weight-loss ratio of fragrant pears is positively related to the degree of *** trained GRNN,SVR,PLSR and BPNN models can be used to predict the weight-loss ratio of fragrant *** BPNN model is the most accurate in predicting the weight-loss ratio of damaged fragrant pears(R^(2)=0.9929;RMSE=0.2138).It has also been proved to have good predictive effect in production practice(R^(2)=0.9377,RMSE=0.7138).The research findings can provide references to predict the delivery quality and time of delivery of Korla fragrant pears.

关键词： Korla fragrant pears weight-loss ratio damages storage time

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A general framework for describing photofission observables of actinides at an average excitation energy below 30 MeV

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Chinese Physics C 2022年第8期46卷 170-183页

作者： Guan-Lin Wang hao-yang lan Xiao-Ming Shi Zhi-Chao Zhu Wen Luo School of Nuclear Science and Technology University of South ChinaHengyang 421001China

A reasonable prediction of photofission observables plays a paramount role in understanding the photofission process and guiding various photofission-induced applications,such as short-lived isotope production,nuclear waste disposal,and nuclear ***,the available experimental data for photofission observables are limited,and the existing models and programs have mainly been developed for neutron-induced fission *** this study,a general framework is proposed for characterizing the photofission observables of actinides,including the mass yield distributions(MYD) and isobaric charge distributions(ICD) of fission fragments and the multiplicity and energy distributions of prompt neutrons(n_(p)) and prompt γ rays(γ_(p)).The framework encompasses various systematic neutron models and empirical models considering the Bohr hypothesis and does not rely on the experimental data as *** models are then validated individually against experimental data at an average excitation energy below 30 MeV,which shows the reliability and robustness of the general ***,we employ this framework to predict the characteristics of photofission fragments and the emissions of prompt particles for typical actinides including ^(232)Th,^(235,238)U and ^(240)*** is found that the ^(238)U(γ,f) reaction is more suitable for producing neutron-rich nuclei compared to the ^(232)Th(γ,f) *** addition,the average multiplicity number of both n_(p) and yp increases with the average excitation energy.

关键词： general framework photofission observables mass yield distributions isobaric charge distributions prompt neutron andγrays

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Cleaner production of 3.5 valent vanadium electrolyte from ammonium metavanadate by ammonia reduction-sulfuric acid dissolution method

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Tungsten 2024年第3期6卷 555-560页

作者： Cheng Wang lan-Jie Li hao Du College of Chemical Engineering University of Chinese Academy of Sciences Institute of Process Engineering National Engineering Research Center of Green Recycling for Strategic Metal Resources Chinese Academy of Sciences Hesteel Group Company Limited

The vanadium redox flow battery(VRFB) has been widely used in large-scale energy storage areas due to the advantages of long lifespan and high safety. However, the high preparation cost of vanadium electrolyte limits ... 详细信息

关键词： Ammonia

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Research progresses and prospects of multi-sphere compound extremes from the Earth System perspective

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Science China Earth Sciences 2024年第2期67卷 343-374页

作者： Zengchao hao yang CHEN College of Water Sciences Beijing Normal UniversityBeijing100875China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing100081China

Compound extremes,whose socioeconomic and ecological impacts are severer than that caused by each event occurring in isolation,have evolved into a hot topic in Earth Science in the past *** the context of climate change,many compound extremes have exhibited increasing frequency and intensity,and shown novel fashions of combinations,posing more pressing demands and tougher challenges to scientific research and disaster prevention and *** article,via a perspective of multi-sphere interactions within the Earth System,systematically reviews the status quo,new scientific understanding,and deficiencies regarding the definition,mechanism,change,attribution,and projection of compound *** study also sorts out existing challenges and outlines a potential roadmap in advancing the study on compound extremes with respect to data requirement,mechanistic diagnosis,numerical modeling,attribution and projection,risk assessment,and adaptive *** directions of compound extremes studies and key research topics that warrant multi-disciplinary and multisectoral coordinated efforts are also *** that climate change has reshaped the type of extremes,a transformation from the traditional single-event perspective to a compound-event perspective is needed for scientific research,disaster prevention and mitigation,and climate change adaptation,calling for bottom-up innovation in research objects,ideas,and *** article will add value to promoting the research on compound extremes and interdisciplinary cooperations.

关键词： Extremes Compound extremes Climate change and risk Multi-sphere interactions

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Snowpack variations and their hazardous effects under climate warming in the central Tianshan Mountains

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Advances in Climate Change Research 2024年第3期15卷 442-451页

作者： Jian-Sheng hao Yan WANG lan-Hai LI Key Laboratory of land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences(CAS)Beijing 100101China Xinjiang Key Laboratory of Water Cycle and Utilization in Arid Zone Urumqi 830011China State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Tianshan Snowcover and Avalanche Observation and Research Station of Xinjiang Xinyuan 835800China CAS Research Center for Ecology and Environment of Central Asia Urumqi 830011China

Climate change alters snowpack evolution,which in turn influences the likelihood of snow avalanches and flood *** lack of systemic observational data on key snow characteristics in high mountains remains a scientific challenge in terms of systematically elucidating the dynamic chain of variations in climate-snowpack-snow *** restricts our understanding and poses challenges in the prediction of snow-related disaster *** such,this study analysed the variations of temperature and snowfall and the physical characteristics of snowpacks based on ground-based observations from the Kunse River Valley situated in the Tianshan Mountains from 1967 to *** results reveal that the temperature increased significantly by 0.32°C per decade(plands,road transportation,water-electricity infrastructure and several other human ***,these insights are critical for providing vital information that can deepen our understanding of the impact of climate change on snowpack characteristics and improve management strategies for snow-related disaster prevention and mitigation.

关键词： Climate change Snowpack variations Snow-related disaster Tianshan Mountains

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Wind disturbance compensated path-following control for fixed-wing UAVs in arbitrarily strong winds

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Chinese Journal of Aeronautics 2024年第2期37卷 431-445页

作者： hao LU lan GAO Yunda YAN Mingzhe HOU Chenliang WANG Hangzhou Innovation Institute Beihang UniversityHangzhou 310051China School of Information Science and Technology Hangzhou Normal UniversityHangzhou 311121China Department of Computer Science University College LondonLondon WC1E 6BTUnited Kingdom Center for Control Theory and Guidance Technology Harbin Institute of TechnologyHarbin 150001China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

Wind is the primary challenge for low-speed fixed-wing unmanned aerial vehicles to follow a predefined flight *** cope with various wind conditions,this paper proposes a wind disturbance compensated path following control strategy where the wind disturbance estimate is incorporated with the nominal guiding vector field to provide the desired airspeed direction for the *** the control input vector for the outer-loop kinematic subsystem needs to satisfy a magnitude constraint,a scaling mechanism is introduced to tune the proportions of the compensation and nominal ***,an optimization problem is formulated to pursue a maximum wind compensation in strong winds,which can be solved analytically to yield two scaling factors.A cascaded inner-loop tracking controller is also designed to fulfill the outer-loop wind disturbance compensated guiding vector ***-fidelity simulation results under sensor noises and realistic winds demonstrate that the proposed path following algorithm is less sensitive to sensor noises,achieves promising accuracy in normal winds,and mitigates the deviation from a desired path in wild winds.

关键词： Path following Guiding vector field Wind disturbance Disturbance rejection Fixed wings

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