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Photochemical pollution in Lanzhou, china - A case study

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Journal of Environmental Sciences 1989年第1期1卷 31-37页

作者： Tang Xiaoyan , Li Jinglong, Dong ZhenXing, Wang Yuying,Wang Wenxing , Qi Liwen, Liu Xiling, zhang Yutian, zhang Xuejin,Tian Bingshen, Jin Suwen , Yang Lingqing and zhang Yixin department of technical physics,peking university, beijing, china. Chinese Reaearch Academy of Eavironmental Sciences, beijing,china. Gansu Provincial Environmental Research Institute, Lanshou, china. Lanshou Petrochemical Engineering Institute, Lanshou, china.

The photochemical air pollution in Xigu district of Lanshou city, Gansu Province was studied during a period of 1981-1984. The extremely high NMHC/NOx ratio and ozone level elevation after rain have been noticed. A series of outdoor and indoor reaction chamber simulation experiments conducted in order to understand the specific conditions. The ozone formation under NMHC/NOx condition and the possible reason for high ozone concentration after rain are discussed.

关键词： photochemical smog oxone air pollution.

Damage Accumulation and Its Effect in Gallium Nitride Film by 208pb27+ Ions of 1.1 MeV/u

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IMP & HIRFL Annual Report 2004年 91-92页

作者： zhang Chonghong, Song Yin, Sun Youmei, Chen Hong, Wang Zhiguang Yao Cunfeng, Zhao Zhiming, Ma Hongji and Nie Rui Institute of physics, Chinese Academy of Sciences, beijing, china. department of technical physics, peking university, beijing china.

Gallium nitride (GaN) has received great attention because its outstanding properties are suitable for the development of novel microelectronic and optoelectronic devices. Ion beam implantation/engineering is an attractive method for device techniques such as selective-area doping or dry etching. The understanding of the damage production in GaN bombarded with energetic ions is fundamentally useful for the solution of such technical issues. Compared with low-energy ion irradiation, effects of swift heavy ions which induce intensive electronic excitation in GaN have been seldom investigated.

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Enhanced Defect Accumulation and Erosion in GaN Bombarded with Low-energy Highly Charged Heavy Ions

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IMP & HIRFL Annual Report 2004年 89-90页

作者： zhang Chonghong, Sun Youmei, Song Yin, Chen Hong, Zhao Zhiming, Yao Cunfeng Wang Zhiguang, Liu Cunbao, Yang Yitao, Ma Hongji and Nie Rui 'Institute of physics, Chinese Academy of Sciences, beijing, china. department of technical physics, peking university, beijing, china.

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Giant Neutron Halo in Exotic Calcium Nuclei

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Giant Neutron Halo in Exotic Calcium Nuclei

CCAST“放射性束物理”研讨会

作者： zhang Shuang-Quan, MENG Jie, ZHOU Shan-Gui,ZENG Jin-Yan department of technical physics, peking university, beijing 100871 Institute of Theoretical physics, Chinese Academy of Sciences, beijing 100080 Center of Theoretical Nuclear physics, National Laboratory ofHeavy Ion Accelerator, Lanzhou 730000 department of physics, peking university, beijing 100871(November 21, 2001)Supported partly by the Major State Basic Research Developmeat Program under Contract Number G2000077407 and theNational Natural Science Foundation of china under Grant Nos. 19847002 and 19935030. e-mail: mengj@***

The properties of even-even Ca isotopes are studied using the relativistic continuum Hartree-Bogoliubov *** calculations reproduce the experimental binding energies E and two neutronseparation energies S very *** predicted neutron drip nuclei is *** the analysis ofsingle-particle energy levels,the occupation of energy levels and nucleon density distribution,gianthaloes are predicted in Ca isotopes with A>60.

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On γ-ray laser

Chinese Science Bulletin 2001年第15期46卷 1238-1242页

作者： qiren zhang Chunyuan Gao Shude Yao department of technical physics Peking University Beijing China

We review various possibilities for realizing a γ-ray laser. We conclude that, similar to the free-electron laser, it is practical to generate the γ-ray laser by the stimulated emission of radiation from wiggling positrons channelled in a periodically bent crystal. It is the time to research this possibility both theoretically and experimentally with big efforts.

关键词： γ-ray laser.

Artificial intelligence for geoscience:Progress,challenges,and perspectives

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The Innovation 2024年第5期5卷 136-160,135页

作者： Tianjie Zhao Sheng Wang Chaojun Ouyang Min Chen Chenying Liu Jin zhang Long Yu Fei Wang Yong Xie Jun Li Fang Wang Sabine Grunwald Bryan MWong Fan zhang Zhen Qian Yongjun Xu Chengqing Yu Wei Han Tao Sun Zezhi Shao Tangwen Qian Zhao Chen Jiangyuan Zeng Huai zhang Husi Letu Bing zhang Li Wang Lei Luo Chong Shi Hongjun Su Hongsheng zhang Shuai Yin Ni Huang Wei Zhao Nan Li Chaolei Zheng Yang Zhou Changping Huang Defeng Feng Qingsong Xu Yan Wu Danfeng Hong Zhenyu Wang Yinyi Lin Tangtang zhang Prashant Kumar Antonio Plaza Jocelyn Chanussot Jiabao zhang Jiancheng Shi Lizhe Wang Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China School of Computer Science China University of GeosciencesWuhan 430078China State Key Laboratory of Mountain Hazards and Engineering Resilience Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610299China Key Laboratory of Virtual Geographic Environment(Ministry of Education of PRC) Nanjing Normal UniversityNanjing 210023China Data Science in Earth Observation Technical University of Munich80333 MunichGermany The National Key Laboratory of Water Disaster Prevention Yangtze Institute for Conservation and DevelopmentHohai UniversityNanjing 210098China Institute of Computing Technology Chinese Academy of SciencesBeijing 100190China School of Geographical Sciences Nanjing University of Information Science and TechnologyNanjing 210044China State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China Soil Water and Ecosystem Sciences DepartmentUniversity of FloridaPO Box 110290GainesvilleFLUSA Materials Science Engineering Program Cooperating Faculty Member in the department of Chemistry and department of physics Astronomy University of CaliforniaCaliforniaRiversideCA 92521USA Institute of Remote Sensing and Geographical Information System School of Earth and Space SciencesPeking UniversityBeijing 100871China Key Laboratory of Computational Geodynamics University of Chinese Academy of SciencesBeijing 100049China International Research Center of Big Data for Sustainable Development Goals Beijing 100094China College of Geography and Remote Sensing Hohai UniversityNanjing 211100China department of Geography The University of Hong KongHong Kong 999077SARChina Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Nanjing 210044China School of Environmental Science and Engineering Nanjing University of Information Science&TechnologyNanjing 210044China Collaborative Inno

This paper explores the evolution of geoscientific inquiry,tracing the progression from traditional physics-based models to modern data-driven approaches facilitated by significant advancements in artificial intelligence(AI)and data collection *** models,which are grounded in physical and numerical frameworks,provide robust explanations by explicitly reconstructing underlying physical ***,their limitations in comprehensively capturing Earth’s complexities and uncertainties pose challenges in optimization and real-world *** contrast,contemporary data-driven models,particularly those utilizing machine learning(ML)and deep learning(DL),leverage extensive geoscience data to glean insights without requiring exhaustive theoretical *** techniques have shown promise in addressing Earth science-related ***,challenges such as data scarcity,computational demands,data privacy concerns,and the“black-box”nature of AI models hinder their seamless integration into *** integration of physics-based and data-driven methodologies into hybrid models presents an alternative *** models,which incorporate domain knowledge to guide AI methodologies,demonstrate enhanced efficiency and performance with reduced training data *** review provides a comprehensive overview of geoscientific research paradigms,emphasizing untapped opportunities at the intersection of advanced AI techniques and *** examines major methodologies,showcases advances in large-scale models,and discusses the challenges and prospects that will shape the future landscape of AI in *** paper outlines a dynamic field ripe with possibilities,poised to unlock new understandings of Earth’s complexities and further advance geoscience exploration.

关键词： Earth utilizing landscape

Study of the structure and the reaction of the light neutron rich nuclei at peking university

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Study of the structure and the reaction of the light neutron...

Study of the response of 10B-doped MCP to wide-energy range neutrons from eV to MeV

2005年全国核反应会议

作者： Y.L.Ye, D.X.Jiang, T.Zheng, Z.H.Li, H.Hua X.Q.Li, D.Y.Pang, GL.zhang, J.Wang,C.Wu, Z.Q.Chen, Q.Y.Hu, Y.C.Ge, J.L.Lou, F.Lu, F.Y.Fan department of technical physics and the DOE Key laboratory of Heavy Ion physics, School of physics, peking university, beijing, 100871, china

Firstly the structure of the lightest neutron rich halo nucleus 6He has been studied via the direct nuclear reaction such as quasi-elastic scattering, breakup reaction and transfer reactions. The experiment was performed at RIKEN-RIBS beam line. Clear particle identification for isotopes of Z=1 to Z=4 were obtained by the telescopes, corresponding to various reaction

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Nuclear Science and Techniques 2024年第8期35卷 132-141页

作者： Qiang Li Li‑Jiao Wang Xiang‑Biao Qiu Jing‑Wen Li Wei Xu Tao Li Ze‑Bin Lin Chang‑Jun Ning Yong‑Hao Chen Rui‑Rui Fan Kang Sun Jing‑Yu Tang Rong zhang Han‑Tao Jing Bo Mei Qi An Hao‑Fan Bai Jiang‑Bo Bai Jie Bao Ping Cao Qi‑Ping Chen Zhen Chen Zeng‑Qi Cui An‑Chuan Fan Chang‑Qing Feng Fan‑Zhen Feng Ke‑Qing Gao Min‑Hao Gu Chang‑Cai Han Zi‑Jie Han Guo‑Zhu He Yong‑Cheng He Yang Hong Yi‑Wei Hu Han‑Xiong Huang Wei‑Hua Jia Hao‑Yu Jiang Wei Jiang Zhi‑Jie Jiang Zheng‑Yao Jin Ling Kang Bo Li Chao Li Gong Li Jia‑Wen Li Xiao Li Yang Li Jie Liu Rong Liu Shu‑Bin Liu Guang‑Yuan Luan Bin‑Bin Qi Jie Ren Zhi‑Zhou Ren Xi‑Chao Ruan Zhao‑Hui Song Zhi‑Xin Tan Sheng‑Da Tang Peng‑Cheng Wang Zhao‑Hui Wang Zhong‑Wei Wen Xiao‑Guang Wu Xuan Wu Li‑Kun Xie Yi‑Wei Yang Han Yi Yong‑Ji Yu Guo‑Hui zhang Lin‑Hao zhang Mo‑Han zhang Qi‑Wei zhang Xian‑Peng zhang Yu‑Liang zhang Yue zhang Zhi‑Yong zhang Mao‑Yuan Zhao Lu‑Ping Zhou Zhi‑Hao Zhou Ke‑Jun Zhu 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 PhysicsChinese Academy of SciencesBeijing 100049China Dongguan Songshan Lake Future School Dongguan 523808China North Night Vision Science&Technology(Nanjing)Research Institute Co.Ltd. Nanjing 211106China Sino‑French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China 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 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 Nuclear physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China Key Laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China 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

Neutron-sensitive microchannel plates(nMCPs)have applications in neutron detection,including energy spectrum measurements,neutron-induced cross sections,and neutron imaging.10B-doped MCPs(B-MCPs)have attracted significant attention owing to their potential for exhibiting a high neutron detection efficiency over a large neutron energy *** spatial and temporal resolutions are useful for neutron energy-resolved ***,their practical applications still face many technical *** this study,a B-MCP with 10 mol%10B was tested for its response to wide-energy neutrons from eV to MeV at the Back-n white neutron source at the china Spallation Neutron *** neutron detection efficiency was calibrated at 1 eV,which is approximately 300 times that of an ordinary MCP and indicates the success of 10 B *** factors that caused the reduction in the detection efficiency were simulated and *** neutron energy spectrum obtained using B-MCP was compared with that obtained by other measurement methods,and showed very good consistency for neutron energies below tens of *** response is more complicated at higher neutron energy,at which point the elastic and nonelastic reactions of all nuclides of B-MCP gradually become *** is beneficial for the detection of neutrons,as it compensates for the detection efficiency of B-MCP for high-energy neutrons.

关键词： Neutron radiation image 10B-doped MCP Neutron response Wide-energy range neutrons

HCN—H2O气体混合物放电化学——研究放电能作用下生物分子生成

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化学学报 1989年第1期47卷 57-59页

作者：戚生初孙平侠李甦王文清赵永和张茂良吴季兰北京大学技术物理系北京大学技术物理系北京

以前研究表明,在γ辐解KCN稀水溶液时,刺迹和整体溶液中存在自由基复合,在通常条件下观测到的生物分子种类和数量很少。大气放电所引发的原始大气反应的化学作用的基本过程与电离辐射类似。一般认为,原始大气反应生成的HCN部分按Strecke... 详细信息

以前研究表明,在γ辐解KCN稀水溶液时,刺迹和整体溶液中存在自由基复合,在通常条件下观测到的生物分子种类和数量很少。大气放电所引发的原始大气反应的化学作用的基本过程与电离辐射类似。一般认为,原始大气反应生成的HCN部分按Strecker反应合成氨基酸,另一部分随降雨过程进入海洋或其它水体,进而以各种可能的途径演化成生命的基础分子。考虑到原始海洋条件下（pH8—8.5,温度0—100℃）,加入水体的HCN可能部分重返大气层并参与由放电或太阳辐射等能源引起的古生物化学过程。本工作以HCN-H2O气体混合物为起始反应物质,模拟研究大气放电转变HCN为生命分子的可能性。

关键词：气体混合物 H2O 生物分子 HCN