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Effects of boundary conditions on vibrating mode of acoustic logging dipole transducer

Science china Earth Sciences 2008年第S2期51卷 195-200页

作者： qiao wenxiao,che {2. & zhang fei state key Laboratory of Petroleum resource and prospecting,china university of Petroleum,beijing 102.49,china 1. state key Laboratory of Petroleum {2. and prospecting China University of Petroleum Beijing 102249 China

Acoustic transducer is an important part of acoustic well logging tool. In this paper,ANSYS software package is used to design acoustic dipole transducer and simulate vibrating mode of the dipole transducer in different mechanical boundary conditions. The results show that boundary conditions influence the number of vibrating mode in the same frequency band and the frequency value of the same vibrating mode. Several acoustic dipole transducers are designed according to the results of numerical simulation and laboratory measurements. The basic frequency of vibrating mode of experi-ment has good agreement with that of simulation. The numerical simulation plays a good guidance role in designing,producing and correctly installing the acoustic dipole transducer.

关键词： acoustic dipole transducer vibrating mode basic frequency acoustic well logging

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Do abrupt cryosphere events in High Mountain Asia indicate earlier tipping point than expected?

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Advances in Climate Change Research 2023年第6期14卷 873-883页

作者： Cun-De XIAO Tong zhang Tao che Zhi-Qiang WEI Tong-Hua WU Lei HUANG Ming-Hu DING {2. LIU Dong-Hui SHANGGUAN fei-Teng WANG Peng-Ling WANG Jie cheN Chun-Hai XU Xin-Wu XU Da-He QIN state key Laboratory of Earth Surface Processes and {2. Ecology Beijing Normal UniversityBeijing 100875China state key Laboratory of Cryospheric Science Chinese Academy of SciencesLanzhou 730000China Faculty of Arts and Sciences Beijing Normal UniversityZhuhai 519000China National Climate Centre China Meteorological AdministrationBeijing 100081China Global Change and Polar Institute Chinese Academy of Meteorological ScienceBeijing 100081China Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610299China

Tipping points of about 16 elements have been identified in Earth system,yet cryospheric tipping point of specific Alpine region has not been *** we analyzed three tipping elements(mountain glacier,snow cover,and permafrost)identified in recent years,evidenced by the facts of frequent occurrence of abrupt massive collapse of glacier mass and the widespread thermakarst of *** 2.15,strikingly abrupt cryosphere events(ACEs)have been consistently observed over a large range of High Mountain Asia(HMA).Those events were un-precedentedly significant in history,leading to collapses of glaciers following by disconnection of glacier tongue from accumulation basin and recession of thermakarst towards higher *** decreasing of snow depth in 2.2. was also observed since 2.2./2.2. winter,coinciding with extreme warming of the *** widespread high warming rates in the last two decades over HMA might have triggered above *** dynamic thresholds of ACEs depend largely on high temperature,especially extreme heat wave,for both glaciers and permafrost,closely related to meltwater as a key factor for reaching initial conditions of abrupt changes,suggesting HMA cryosphere is a tipping element under the global warming level of 1.1℃.The ACEs can cause tremendous damage to local ecosystem and socioeconomy,measures to mitigate risks should be taken when the tipping points are reached.

关键词： Abrupt glacier change Thermakarst Snow depth Tipping point Early warning system

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CEPC Technical Design Report

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Radiation Detection Technology and Methods 2024年第1期8卷 I0003-I0016,1-1091页

作者： Waleed Abdallah Tiago Carlos Adorno de Freitas Konstantin Afanaciev Shakeel Ahmad Ijaz Ahmed Xiaocong Ai Abid Aleem Wolfgang Altmannshofer Fabio Alves Weiming An Rui An Daniele Paolo Anderle Stefan Antusch Yasuo Arai Andrej Arbuzov Abdesslam Arhrib Mustafa Ashry Sha Bai Yu Bai Yang Bai Vipul Bairathi Csaba Balazs Philip Bambade Yong Ban Tripamo Bandyopadhyay Shou-Shan Bao Desmond P.Barber Ayse Bat Varvara Batozskaya Subash Chandra Behera Alexander Belyaev Michele Bertucci Xiao-Jun Bi Yuanjie Bi Tianjian Bian Fabrizio Bianchi Thomas Biekotter Michela Biglietti Shalva Bilanishvili Deng Binglin Denis Bodrov Anton Bogomyagkov Serge Bondarenko Stewart Boogert Maarten Boonekamp Marcello Borri Angelo Bosotti Vincent Boudry Mohammed Boukidi Igor Boyko Ivanka Bozovic Giuseppe Bozzi Jean-Claude Brient Anastasiia Budzinskaya Masroor Bukhari Vladimir Bytev Giacomo Cacciapaglia Hua Cai Wenyong Cai Wujun Cai Yijian Cai Yizhou Cai Yuchen Cai Haiying Cai Huacheng Cai Lorenzo Calibbi Junsong Cang Guofu Cao Jianshe Cao Antoine Chance Xuejun Chang Yue Chang Zhe Chang Xinyuan Chang Wei Chao Auttakit Chatrabhuti Yimin che Yuzhi che Bin chen Danping chen Fuqing chen Fusan chen Gang chen Guoming chen Hua-Xing chen Huirun chen Jinhui chen Ji-Yuan chen Kai chen Mali chen Mingjun chen Mingshui chen Ning chen Shanhong chen Shanzhen chen Shao-Long chen Shaomin chen Shiqiang chen Tianlu chen Wei chen Xiang chen Xiaoyu chen Xin chen Xun chen Xurong chen Ye chen Ying chen Yukai chen Zelin chen Zilin chen Gang chen Boping chen Chunhui chen Hok Chuen cheng Huajie cheng Shan cheng Tongguang cheng Yunlong Chi Pietro Chimenti Wen Han Chiu Guk Cho Ming-Chung Chu Xiaotong Chu Ziliang Chu Guglielmo Coloretti Andreas Crivellin Hanhua Cui Xiaohao Cui Zhaoyuan Cui Brunella D'Anzi Ling-Yun Dai Xinchen Dai Xuwen Dai Antonio De Maria Nicola De Filippis Christophe De La Taille Francesca De Mori Chiara De Sio Elisa Del Core Shuangxue Deng Wei-Tian Deng Zhi Deng Ziyan Deng Bhupal Dev Tang Dewen Biagio Di Micco Ran Ding Siqin Dingl Yadong Ding Haiyi Dong Jianin AGH university of Science and Technology Faculty of Physics and Applied Computer ScienceKrakow Anhui university HefeiAnhui Applied Physics Department Federal Urdu University of ArtsScience and TechnologyIslamabad Banaras Hindu university Institute of ScienceVaranasi Bandirma Onyedi Eylul university Bandirma Beihang university Beijing beijing Computational Science Research Center Beijing beijing Conveyi LTD Beijing beijing Glass Research Institute Co. LtdBeijing beijing Institute of Technology Beijing beijing Normal university Beijing Brown university ProvidenceRI Budker Institute of Nuclear Physics Novosibirsk Cadi Ayyad university Laboratory of Fundamental and Applied PhysicsPolydisciplinary FacultyMarrakech Cairo university Giza Center for Theory and Computation National Tsing Hua UniversityHsinchu Central china Normal university WuhanHubei Central South university ChangshaHunan Centro de Fisica Teorica de Particulas Universidade Tecnica de LisboaLisboa chengdu KaitengSifang Digital Radio&TV Equipment Co. LtdChengduSichuan china academy of engineering physics MianyangSichuan china building materials academy Beijing china Center of Advanced Science and Technology Beijing china Institute of Atomic Energy Beijing china Jiliang university HangzhouZhejiang china Nuclear Instrument CO. LTDBeijing china university of Geosciences Beijing china university of Geosciences WuhanHubei china university of Mining and Technology XuzhouJiangsu china West Normal university NanchongSichuan Chongqing university Department of PhysicsChongqing Chulalongkorn university Bangkok City university of Hong Kong Department of PhysicsHong Kong Cockcroft Institute Daresbury Cornell university IthacaNY CPPM(AMU/IPhU&CNRS/INP) Marseille Dalian Minzu university DalianLiaoning Dalian university of Technology Department of PhysicsDalian Deutsches Elektronen-Synchrotron DESY Hamburg Dzhelepov Laboratory of Nuclear Problems of Joint Institute for Nuclear Research(DLNP JINR) Dubna East china university Of Science And Technol

The Circular Electron Positron Collider(CEPC)is a large scientific project initiated and hosted by china,fostered through extensive collaboration with international *** complex comprises four accelerators:a 30 GeV Linac,a 1.1 GeV Damping Ring,a Booster capable of achieving energies up to 180 GeV,and a Collider operating at varying energy modes(Z,W,H,and tt).The Linac and Damping Ring are situated on the surface,while the subterranean Booster and Collider are housed in a 100 km circumference underground tunnel,strategically accommodating future expansion with provisions for a potential Super Proton Proton Collider(SPPC).The CEPC primarily serves as a Higgs *** its baseline design with synchrotron radiation(SR)power of 30 MW per beam,it can achieve a luminosity of 5×10^(34)cm^(-2.s^(-1)per interaction point(IP),resulting in an integrated luminosity of 13 ab^(-1)for two IPs over a decade,producing 2.6 million Higgs *** the SR power to 50 MW per beam expands the CEPC's capability to generate 4.3 million Higgs bosons,facilitating precise measurements of Higgs coupling at sub-percent levels,exceeding the precision expected from the HL-LHC by an order of *** Technical Design Report(TDR)follows the Preliminary Conceptual Design Report(Pre-CDR,2.15)and the Conceptual Design Report(CDR,2.18),comprehensively detailing the machine's layout,performance metrics,physical design and analysis,technical systems design,R&D and prototyping efforts,and associated civil engineering ***,it includes a cost estimate and a preliminary construction timeline,establishing a framework for forthcoming engineering design phase and site selection *** is anticipated to begin around 2.2.-2.2.,pending government approval,with an estimated duration of 8 *** commencement of experiments and data collection could potentially be initiated in the mid-2.30s.

关键词： initiated exceeding precise

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A joint call for actions to advance taxonomy in china

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Zoological Systematics 2022年第3期47卷 188-197页

作者： Chaodong Zhu Arong Luo Ming Bai Michael COrr Zhonge Hou Siqin Ge Jun chen Yibo Hu Xuming Zhou Gexia qiao Hongzhi Kong Limin Lu {2. Jin Lei Cai Xinli Wei Ruilin Zhao Wei Miao Qingfeng Wang Zhongli Sha Qiang Lin Meng Qu Jianping Jiang Jiatang Li Jing che Xuelong Jiang Xiaoyong chen Lianming Gao Zongxin Ren Chunlei Xiang Shixiao Luo Donghui Wu Dong Liu Yanqiong Peng Tao Su chenyang Cai Tianqi Zhu Wanzhi Cai Xingyue Liu Hu Li Huaijun Xue Zhen Ye Xuexin chen Pu Tang Shujun Wei Hong Pang Qiang Xie Feng zhang Feng zhang Xianjin Peng Aibing zhang Taiping Gao Changfa Zhou chen Shao Libin Ma Zhaoming Wei Yunxia Luan Ziwei Yin Wu Dai Cong Wei Xiaolei Huang Jingxian Liu Xiangsheng chen Tianci Yi Zhisheng zhang Zhulidezi Aishan Qin Li Hongying Hu CAS key Laboratory of Zoological Systematics and Evolution Institute of ZoologyChinese Academy of SciencesBeijing 100101China CAS key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China state key Laboratory of Systematic and Evolutionary Botany Institute of BotanyChinese Academy of SciencesBeijing 100093China state key Laboratory of Mycology(SKLM) Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China CAS key Laboratory of Aquatic Biodiversity and Conservation Institute of HydrobiologyChinese Academy of SciencesWuhan 430072China Wuhan Botanical Garden Chinese Academy of SciencesWuhan 430074China Department of Marine Organism Taxonomy&Phylogeny Institute of OceanologyChinese Academy of SciencesQingdao 266071China CAS key Laboratory of Tropical Marine Bio-resources and Ecology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China CAS key Laboratory of Mountain Ecological Restoration and Bioresource Utilization&Ecological Restoration and Biodiversity Conservation key Laboratory of Sichuan Province Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041China state key Laboratory of Genetic {2.s and Evolution&Yunnan key Laboratory of Biodiversity and Ecological Security of Gaoligong Mountain Kunming Institute of ZoologyChinese Academy of SciencesKunming 650221China CAS key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China CAS key Laboratory of Plant resource Conservation and Sustainable Utilization South China Botanical GardenChinese Academy of SciencesGuangzhou 510650China CAS key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China CAS key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglunMenglaYunnan 66630

Taxonomy plays an important role in understanding the origin, evolution, and ecological functionality of biodiversity. There are large number of unknown species yet to be described by taxonomists, which together with their ecosystem services cannot be effectively protected prior to description. Despite this, taxonomy has been increasingly underrated insufficient funds and permanent positions to retain young talents. Further, the impact factordriven evaluation systems in china exacerbate this downward trend, so alternative evaluation metrics are urgently necessary. When the current generation of outstanding taxonomists retires,there will be too few remaining taxonomists left to train the next generation. In light of these challenges, all co-authors worked together on this paper to analyze the current situation of taxonomy and put out a joint call for immediate actions to advance taxonomy in china.

关键词： Endangered taxonomists morphology-based taxonomy integrative taxonomy capacity building systematics

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Mapping wetland changes in china between 1978 and 2.08

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Chinese Science Bulletin 2012年第22期57卷 2813-2823页

作者： NIU ZhenGuo zhang HaiYing WANG XianWei YAO WenBo ZHOU DeMin ZHAO KuiYi ZHAO Hui LI NaNa HUANG HuaBing LI CongCong YANG Jun LIU CaiXia LIU Shuang WANG Lin LI Zhan YANG ZhenZhong qiao {2. ZHENG YaoMin cheN YanLei SHENG YongWei GAO XiaoHong ZHU WeiHong WANG WenQing WANG Hong WENG YongLing ZHUANG DaFang LIU JiYuan LUO ZhiCai cheNG Xiao GUO ZiQi GONG Peng state key Laboratory of Remote Sensing Science Jointly Sponsored by Institute of Remote Sensing ApplicationsChinese Academy of Sciences and Beijing Normal UniversityBeijing 100101China Ministry of Education key Laboratory for Earth System Modeling Center for Earth System ScienceInstitute for Global Change StudiesTsinghua UniversityBeijing 100084China Department of resource Environment and Tourism Capital Normal UniversityBeijing 100037China Northeast Institute of Geography and Agricultural Ecology Chinese Academy of SciencesChangchun 130012China Department of Geography and Remote Sensing Beijing Normal UniversityBeijing 100875China College of Forestry Beijing Forestry UniversityBeijing 100083China Department of Environmental Science Policy and ManagementUniversity of CaliforniaBerkeley94720USA Department of Geography University of CaliforniaLos Angeles90095USA Department of Life and Geographic Sciences Qinghai Normal UniversityXining 810008China Department of Geography Yanbian UniversityYanbian 133002China School of Environment and Ecology Xiamen UniversityXiamen 361005China School of Geographical Information Science Hohai UniversityNanjing 211100China School of Surveying and Mapping Transportation Engineering Southeast UniversityNanjing 210096China Institute of Geographical Sciences and Natural resources Research Chinese Academy of SciencesBeijing 100101China School of Surveying and Mapping Wuhan UniversityWuhan 430079China

Four wetland maps for all china have been produced,based on Landsat and CBERS-02. remote sensing data between 1978 and 2.08 (1978,1990,2.00 and 2.08).These maps were mainly developed by manual interpretation and validated by substantial field investigation in *** on these maps,we analyzed the 2.08 wetland distribution in china and discussed wetland changes and their drivers over the past 30 years.(i) There were about 32.097 km 2.of wetlands in 2.08,for which inland marshes or swamps were the most common wetland type (35%),with lakes (2.%) *** of the wetlands were in Heilongjiang,Inner Mongolia,Qinghai and Tibet,occupying about 55% of the national wetland area.(ii) From 1978 to 2.08,china's wetland area continually and significantly decreased,by about 33% based on changes in the wetland *** was in sharp contrast to the increase in artificial wetlands,which increased by about 12.%.Inland marshes accounted for the main loss of total wetlands from 1978 to *** 2.00 through 2.08,riverine and lacustrine wetlands constituted the main wetland *** however,the rate of wetland loss decreased from 552. to 831 km 2./a.(iii) The change ratio of lost natural wetlands (including inland and coastal wetlands) to non-wetlands has decreased slightly over the past 30 *** 1978 to 1990,nearly all natural wetlands (98%) lost were transformed into ***,the ratio declined to 86% from 1990 to 2.00,and to 77% from 2.00 to 2.08.(iv) All Chinese provinces were divided into three groups according to patterns of wetland changes,which could relate to the driving forces of such *** was completely different from other provinces,as it was one representative example in which there was a net wetland increase,because of global warming and decreased human activity since *** economic development caused considerable wetland loss in most eastern provinces,and artificial wetlands increased.

关键词：湿地变化中国地图映射地球资源卫星内陆湿地人工湿地全球气候变暖湿地面积

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