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Evolution of the novel coronavirus from the ongoing Wuhan outbreak and modeling of its spike protein for risk of human transmission 被引量:782
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作者 Xintian Xu Ping Chen +5 位作者 Jingfang Wang Jiannan Feng Hui Zhou Xuan Li Wu Zhong Pei Hao 《Science China(Life Sciences)》 SCIE CAS CSCD 2020年第3期457-460,共4页
Dear Editor,The occurrence of concentrated pneumonia cases in Wuhan city,Hubei province of China was first reported on December 30,2019 by the Wuhan Municipal Health Commission(WHO,2020).The pneumonia cases were found... Dear Editor,The occurrence of concentrated pneumonia cases in Wuhan city,Hubei province of China was first reported on December 30,2019 by the Wuhan Municipal Health Commission(WHO,2020).The pneumonia cases were found to be linked to a large seafood and animal market in Wuhan,and measures for sanitation and disinfection were taken swiftly by the local government agency.The Centers for Disease Control and Prevention(CDC)and Chinese health authorities later determined and announced that a novel coronavirus(CoV),denoted as 2019-nCoV,had caused the pneumonia outbreak in Wuhan city(CDC,2020).Scientists from multiple groups had obtained the virus samples from hospitalized patients(Normile,2020).The isolated viruses were morphologically identical when observed under electron microscopy. 展开更多
关键词 WUHAN EVOLUTION measures
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从智能电网到能源互联网:基本概念与研究框架 被引量:767
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作者 董朝阳 赵俊华 +1 位作者 文福拴 薛禹胜 《电力系统自动化》 EI CSCD 北大核心 2014年第15期1-11,共11页
以化石能源集中式利用为特征的传统经济和社会发展模式正在逐步发生变革,而以新能源技术和互联网技术为代表的第三次工业革命正在兴起。作为第三次工业革命的核心技术,能源互联网力图结合可再生能源技术与互联网技术,推动分布式可再生... 以化石能源集中式利用为特征的传统经济和社会发展模式正在逐步发生变革,而以新能源技术和互联网技术为代表的第三次工业革命正在兴起。作为第三次工业革命的核心技术,能源互联网力图结合可再生能源技术与互联网技术,推动分布式可再生能源的大规模利用与分享,促进电力、交通、天然气等多种复杂网络系统的相互融合,最终实现改变能源利用模式,推动经济与社会可持续发展的目的。在此背景下,展望了能源互联网的发展前景,并试图建立其基本的研究框架。首先,给出了能源互联网的初步定义,并概述了能源互联网的基本架构及其组成。随后,针对广域内分布式设备的协调与控制、电力系统与交通系统的融合、电力系统与天然气网络的融合、信息物理建模及安全等几个核心问题,探讨了能源互联网研究中可能面临的主要挑战。 展开更多
关键词 能源互联网 智能电网 天然气网络 电气化交通 信息物理建模 信息物理安全性
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Measurements of dihadron correlations relative to the event plane in Au+Au collisions at√^(S)NN=200 GeV 被引量:351
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作者 H.Agakishiev M.M.Aggarwal +140 位作者 Z.Ahammed A.V.Alakhverdyants I.Alekseev J.Alford B.D.Anderson C.D.Anson D.Arkhipkin G.S.Averichev J.Balewski D.R.Beavis N.K.Behera R.Bellwied M.J.Betancourt R.R.Betts A.Bhasin A.K.Bhat H.Bichsel J.Bieleik J.Bielcikova B.Biritz L.C.Bland W.Borowski J.Bouchet E.Braidot A.V.Brandin A.Bridgeman S.G.Brovko E.Bruna S.Bueltmann I.Bunzarov T.P.Burton X.Z.Cai H.Caines M.Calderon de la Barca Sanchez D.Cebra R.Cendejas M.C.Cervantes Z.Chajecki P.Chaloupka S.Chattopadhyay H.F.Chen J.H.Chen J.Y.Chen L.Chen J.Cheng M.Cherney A.Chikanian K.E.Choi W.Christie P.Chung M.J.M.Codrington R.Corliss J.G.Cramer H.J.Crawford S.Dash A.Davila Leyva L.C.De Silvat R.R.Debbe T.G.Dedovich A.A.Derevschikov R.Derradi de Souza L.Didenko P.Djawotho S.M.Dogra X.Dong J.L.Drachenberg J.E.Draper J.C.Dunlop L.G Efimov M.Elnim J.Engelage G Eppley M.Estienne L.Eun O.Evdokimov R.Fatemi J.Fedorisin A.Feng R.G.Fersch P.Filip E.Finch V.Fine Y.Fisyak C.A.Gagliardi D.R.Gangadharan A.Geromitsos F.Geurts P.Ghosh Y.N.Gorbunov A.Gordon O.Grebenyuk D.Grosnick S.M.Guertin A.Gupta W.Guryn B.Haag O.Hajkova A.Hamed L-X.Han J.W.Harris J.P.Hays-Wehle M.Heinz S.Heppelmann A.Hirsch E.Hjort G.W.Hoffmann D.J.Hofiman B.Huang H.Z.Huang T.J.Humanic L.Huo G.Igo P.Jacobs W.W.Jacobs C.Jena F.Jin J.Joseph E.G.Judd S.Kabana K.Kang J.Kapitan K.Kauder H.Ke D.Keane A.Kechechyan D.Kettler D.P.Kikola J.Kiryluk A.Kisiel V.Kizka A.G.Knospe D.D.Koetke T.Kollegger J.Konzer I.Koralt L.Koroleva W.Korsch L.Kotchenda V.Kouchpil P.Kravtsov K.Krueger 《Chinese Physics C》 SCIE CAS CSCD 2021年第4期198-241,共44页
Dihadron azimuthal correlations containing a high transverse momentum(pr)trigger particle are sensit-ive to the properties of the nuclear medium created at RHIC through the strong interactions occurring between the tr... Dihadron azimuthal correlations containing a high transverse momentum(pr)trigger particle are sensit-ive to the properties of the nuclear medium created at RHIC through the strong interactions occurring between the traversing parton and the medium,ie.jet-quenching.Previous measurements revealed a strong modification to di-hadron azimuthal correlations in Au+Au collisions with respect to ptp and d+Au collisions.The modification in-creases with the collision centrality,suggesting a path-length or energy density dependence to the je-quenching ef-fect.This paper reports STAR measurements of dihadron azimuthal correlations in mid-central(20%-60%)Au+Au collisions at√^(S)NN=200 GeV as a function of the trigger particle's azimuthal angle relative to the event plane,Ф_(s)=|Ф_(t)-ψ_(Ep)|.The azimuthal correlation is studied as a function of both the trigger and associated particle pr.The subtractions of the combinatorial background and anisotropic flow,assuming Zero Yield At Minimum(ZYAM),are described.The correlation results are first discussed with subtraction of the even harmonic(elliptic and quadrangu-lar)flow backgrounds.The away-side correlation is strongly modifed,and the modification varies withФ_(s),with a double-peak structure for out-of-plane trigger particles.The near-side ridge(long range pseudo-rapidity△_(η)correla-tion)appears to drop with increasingФ_(s)while the jet-like component remains approximately constant.The correla-tion functions are further studied with the subtraction of odd harmonic triangular flow background arising from fluc-tuations.It is found that the triangular flow,while responsible for the majority of the amplitudes,is not sufficient to explain theφs-dependence of the ridge or the away-side double-peak structure.The dropping ridge withФ_(s)could be attributed to aФ_(s)-dependent lliptie anisotropy;however,the physics mechanism of the ridge remains an open ques-tion.Even with aФ_(s)-dependent elliptic flow,the away-side correlation structure is robust.These results,with exte 展开更多
关键词 relativistic heavy ion collisions dihadron correlations jet-medium interactions anisotropic flow background event plane
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超轻多孔金属材料的多功能特性及应用 被引量:253
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作者 卢天健 何德坪 +3 位作者 陈常青 赵长颖 方岱宁 王晓林 《力学进展》 EI CSCD 北大核心 2006年第4期517-535,共19页
超轻多孔金属是近年来随着多样化需求的材料制备以及机械加工技术的迅速发展而出现的一类新颖多功能材料,是材料的选择及其性能研究的新课题,本文介绍有关多孔金属材料与结构基础研究的国内外研究现状和发展趋势,涉及材料制备、性能表... 超轻多孔金属是近年来随着多样化需求的材料制备以及机械加工技术的迅速发展而出现的一类新颖多功能材料,是材料的选择及其性能研究的新课题,本文介绍有关多孔金属材料与结构基础研究的国内外研究现状和发展趋势,涉及材料制备、性能表征等方面,着重于探讨多孔金属的多功能复合特性及其在国民经济和高技术中的应用。 展开更多
关键词 多孔金属材料 制备工艺 力学行为 物理波传播 传热特性
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Spatiotemporal characteristics, patterns, and causes of land-use changes in China since the late 1980s 被引量:271
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作者 LIU Jiyuan KUANG Wenhui +13 位作者 ZHANG Zengxiang XU Xinliang QIN Yuanwei NING Jia ZHOU Wancun ZHANG Shuwen LI Rendong YAN Changzhe WU Shixin SHI Xuezheng JIANG Nan YU Dongsheng PAN Xianzhang CHI Wenfeng 《Journal of Geographical Sciences》 SCIE CSCD 2014年第2期195-210,共16页
Land-use/land-cover changes (LUCCs) have links to both human and nature inter- actions. China's Land-Use/cover Datasets (CLUDs) were updated regularly at 5-year inter- vals from the late 1980s to 2010, with stand... Land-use/land-cover changes (LUCCs) have links to both human and nature inter- actions. China's Land-Use/cover Datasets (CLUDs) were updated regularly at 5-year inter- vals from the late 1980s to 2010, with standard procedures based on Landsat TM/ETM+ im- ages. A land-use dynamic regionalization method was proposed to analyze major land-use conversions. The spatiotemporal characteristics, differences, and causes of land-use changes at a national scale were then examined. The main findings are summarized as fol- lows. Land-use changes (LUCs) across China indicated a significant variation in spatial and temporal characteristics in the last 20 years (1990-2010). The area of cropland change de- creased in the south and increased in the north, but the total area remained almost un- changed. The reclaimed cropland was shifted from the northeast to the northwest. The built-up lands expanded rapidly, were mainly distributed in the east, and gradually spread out to central and western China. Woodland decreased first, and then increased, but desert area was the opposite. Grassland continued decreasing. Different spatial patterns of LUC in China were found between the late 20th century and the early 21st century. The original 13 LUC zones were replaced by 15 units with changes of boundaries in some zones. The main spatial characteristics of these changes included (1) an accelerated expansion of built-up land in the Huang-Huai-Hai region, the southeastern coastal areas, the midstream area of the Yangtze River, and the Sichuan Basin; (2) shifted land reclamation in the north from northeast China and eastern Inner Mongolia to the oasis agricultural areas in northwest China; (3) continuous transformation from rain-fed farmlands in northeast China to paddy fields; and (4) effective- ness of the "Grain for Green" project in the southern agricultural-pastoral ecotones of Inner Mongolia, the Loess Plateau, and southwestern mountainous areas. In the last two decades, although climate change 展开更多
关键词 satellite remote sensing land-use change CHARACTERISTICS spatial pattern China
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Toward New-Generation Intelligent Manufacturing 被引量:265
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作者 Zhou Ji Li Peigen +3 位作者 Zhou Yanhong Wang Baicun Zang Jiyuan Meng Liu 《Engineering》 2018年第1期11-20,共10页
Intelligent manufacturing is a general concept that is under continuous development. It can be categorized into three basic paradigms: digital manufacturing, digital-networked manufacturing, and newgeneration intelli... Intelligent manufacturing is a general concept that is under continuous development. It can be categorized into three basic paradigms: digital manufacturing, digital-networked manufacturing, and newgeneration intelligent manufacturing. New-generation intelligent manufacturing represents an indepth integration of new-generation artificial intelligence (AI) technology and advanced manufacturing technology. It runs through every link in the full life-cycle of design, production, product, and service. The concept also relates to the optimization and integration of corresponding systems; the continuous improvement of enterprises' product quality, performance, and service levels; and reduction in resources consumption. New-generation intelligent manufacturing acts as the core driving force of the new indus- trial revolution and will continue to he the main pathway for the transformation and upgrading of the manufacturing industry in the decades to come. Human-cyher-physical systems (HCPSs) reveal the tech- nological mechanisms of new-generation intelligent manufacturing and can effectively guide related the- oretical research and engineering practice. Given the sequential development, cross interaction, and iterative upgrading characteristics of the three basic paradigms of intelligent manufacturing, a technol- ogy roadmap for "parallel promotion and integrated development" should he developed in order to drive forward the intelligent transformation of the manufacturing industry in China. 展开更多
关键词 ADVANCED MANUFACTURING NEW-GENERATION INTELLIGENT MANUFACTURING Human-cyber-physical systemNew-generation AIBasic paradigms PARALLEL promotionIntegrated development
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Resource diversity of Chinese macrofungi:edible,medicinal and poisonous species 被引量:259
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作者 Fang Wu Li-Wei Zhou +3 位作者 Zhu-Liang Yang Tolgor Bau Tai-Hui Li Yu-Cheng Dai 《Fungal Diversity》 SCIE 2019年第5期1-76,共76页
The huge land areas in China provide highly diverse habitats for macrofungi.Of these macrofungi,many are directly related to people’s daily life and have been utilized by ancient Chinese for at least 6800 years.In th... The huge land areas in China provide highly diverse habitats for macrofungi.Of these macrofungi,many are directly related to people’s daily life and have been utilized by ancient Chinese for at least 6800 years.In this study,we evaluate the current known resource diversity of Chinese macrofungi.A total of 1662 taxa are summarized,and all species names and their authorities have been checked and corrected according to authentic mycological databases.Among the 1662 taxa,1020,692,and 480 are considered to be edible,medicinal and poisonous mushrooms,respectively.A few of edible macrofungi in China are commonly used for commercial production.All known medicinal functions are labeled for medicinal species.The most common medicinal functions possessed by Chinese macrofungi are antitumor or anticancer,followed by antioxidant and antimicrobial.A total of 277 Chinese macrofungi are edible simultaneously with certain medicinal functions and without known toxicity.These species could be treated as“Gold Mushrooms”.Contrarily,193 edible and/or medicinal species are also recognized as poisonous mushrooms.To avoid poisoning caused by these species,ingestion either in a proper way or in small amounts is important.However,the mycotoxins metabolized by these poisonous species could be a huge wealth of natural products yet to be explored.How to utilize these Chinese macrofungal resources is a critical to benefit humans worldwide. 展开更多
关键词 Economic fungi Edible mushroom Fungal toxicity Medicinal function NOMENCLATURE
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中国大陆现今地壳运动和构造变形 被引量:190
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作者 王琪 张培震 +7 位作者 牛之俊 J.T.Freymueller 赖锡安 李延兴 朱文耀 刘经南 R.Bilham K.M.Larson 《中国科学(D辑)》 CSCD 北大核心 2001年第7期529-536,共8页
全球定位系统(GPS)揭示的中国大陆现今运动场清晰地表现出了以活动地块 为单元的分块运动特征,不同的活动地块具有不同的运动和变形方式.GPS观测到的阿 尔金断裂的左旋走滑速率仅(5.l± 2.5)mm/a,龙门山断... 全球定位系统(GPS)揭示的中国大陆现今运动场清晰地表现出了以活动地块 为单元的分块运动特征,不同的活动地块具有不同的运动和变形方式.GPS观测到的阿 尔金断裂的左旋走滑速率仅(5.l± 2.5)mm/a,龙门山断裂的挤压缩短速率为(6.7± 3.0) mm/a,华南地块相对于欧亚大陆向东的运动速率是 11~14mm/a,这些结果均不支持青 藏高原北部沿主要走滑断裂向东大规模挤出的假说.中国大陆以活动地块为单元的现 今构造变形可能与大陆岩石圈的结构和性质有关,上地壳以脆性变形为主,下地壳和 上地幔以粘塑性的流变为特征,从底部驱动着上覆脆性地块的整体运动. 展开更多
关键词 全球定位系统 GPS 地壳运动 活动地块 岩石圈动力学 中国大陆 构造变形
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Latest research advances on magnesium and magnesium alloys worldwide 被引量:195
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作者 Jiangfeng Song Jia She +1 位作者 Daolun Chen Fusheng Pan 《Journal of Magnesium and Alloys》 SCIE 2020年第1期1-41,共41页
In the past two years,significant progresses have been achieved in high-performance cast and wrought magnesium and magnesium alloys,magnesium-based composites,advanced cast technologies,advanced processing technologie... In the past two years,significant progresses have been achieved in high-performance cast and wrought magnesium and magnesium alloys,magnesium-based composites,advanced cast technologies,advanced processing technologies,and functional magnesium materials,such as Mg ion batteries,hydrogen storage Mg materials,bio-magnesium alloys,etc.Great contributions to the development of new magnesium alloys and their processing technologies have been made by Chongqing University,Shanghai Jiaotong University,Chinese Academy of Sciences,Helmholtz Zentrum Geesthacht,Queensland University,Brunel University,etc.This review paper is aimed to summarize the latest important advances in cast magnesium alloys,wrought magnesium alloys and functional magnesium materials worldwide in 2018–2019,including both the development of new materials and the innovation of their processing technologies.Based on the issues and challenges identified here,some future research directions are suggested,including further development of high-performance magnesium alloys having high strength and superior plasticity together with high corrosion resistance and low cost,and fundamental research on the phase diagram,diffusion,precipitation,etc.,as well as the development of advanced welding and joining technology. 展开更多
关键词 Cast magnesium alloys Wrought magnesium alloys Functional magnesium materials Cast and processing technologies Corrosion and surface treatment International standard
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高延性纤维增强水泥基复合材料的研究进展及应用 被引量:194
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作者 LI Victor C 《硅酸盐学报》 EI CAS CSCD 北大核心 2007年第4期531-536,共6页
高延性水泥基复合材料(engineered cementitious composite,ECC)是经系统的微观力学设计,在拉伸和剪切荷载下呈现高延展性的一种纤维增强水泥基复合材料。综述了ECC的研究进展,介绍了配筋ECC结构的耐久性、安全性及可持续性等混凝土必... 高延性水泥基复合材料(engineered cementitious composite,ECC)是经系统的微观力学设计,在拉伸和剪切荷载下呈现高延展性的一种纤维增强水泥基复合材料。综述了ECC的研究进展,介绍了配筋ECC结构的耐久性、安全性及可持续性等混凝土必须满足的关键性能。根据ECC近来的应用情况及在工程上推广应用的需要,总结了ECC长期性能方面的研究结果。 展开更多
关键词 复合材料 纤维 延展性 耐久性 可持续性 安全性 设计 基础设施
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Destruction of the North China Craton 被引量:185
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作者 ZHU RiXiang XU YiGang +3 位作者 ZHU Guang ZHANG HongFu XIA QunKe ZHENG TianYu 《Science China Earth Sciences》 SCIE EI CAS 2012年第10期1565-1587,共23页
A National Science Foundation of China (NSFC) major research project, Destruction of the North China Craton (NCC), has been carried out in the past few years by Chinese scientists through an in-depth and systemati... A National Science Foundation of China (NSFC) major research project, Destruction of the North China Craton (NCC), has been carried out in the past few years by Chinese scientists through an in-depth and systematic observations, experiments and theoretical analyses, with an emphasis on the spatio-temporal distribution of the NCC destruction, the structure of deep earth and shallow geological records of the craton evolution, the mechanism and dynamics of the craton destruction. From this work the foUowing conclusions can be drawn: (1) Significant spatial heterogeneity exists in the NCC lithospheric thickness and crustal structure, which constrains the scope of the NCC destruction. (2) The nature of the Paleozoic, Mesozoic and Cenozoic sub-continental lithospheric mantle (CLM) underneath the NCC is characterized in detail. In terms of water content, the late Mesozoic CLM was rich in water, but Cenozoic CLM was highly water deficient. (3) The correlation between magmatism and surface geological response confirms that the geological and tectonic evolution is governed by cratonic destruction processes. (4) Pacific subduction is the main dynamic factor that triggered the destruction of the NCC, which highlights the role of cratonic destruction in plate tectonics. 展开更多
关键词 NSFC major research project research progress craton destruction North China Craton
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PM_(2.5) in China:Measurements,sources,visibility and health effects,and mitigation 被引量:184
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作者 David Y.H.Pui Sheng-Chieh Chen Zhili Zuo 《Particuology》 SCIE EI CAS CSCD 2014年第2期1-26,共26页
Concern over the health effects of fine particles in the ambient environment led the U.S. Environmental Protection Agency to develop the first standard for PM2.5 (particulate matter less than 2.5 μm) in 1997. The P... Concern over the health effects of fine particles in the ambient environment led the U.S. Environmental Protection Agency to develop the first standard for PM2.5 (particulate matter less than 2.5 μm) in 1997. The Particle Technology Laboratory at the University of Minnesota has helped to establish the PM2.5 standard by developing many instruments and samplers to perform atmospheric measurements. In this paper, we review various aspects of PM2.5, including its measurement, source apportionment, visibility and health effects, and mitigation. We focus on PM2.s studies in China and where appropriate, compare them with those obtained in the U.S. Based on accurate PM2.5 sampling, chemical analysis, and source apportionment models, the major PM2.5 sources in China have been identified to be coal combustion, motor vehicle emissions, and industrial sources. Atmospheric visibility has been found to correlate well with PM2.s concentration. Sulfate, ammonium, and nitrate carried by PM2.s, commonly found in coal burning and vehicle emissions, are the dominant contributors to regional haze in China. Short-term exposure to PM2.s is strongly associated with the increased risk of morbidity and mortality from cardiovascular and respiratory diseases in China. The strategy for PMzs mitigation must be based on reducing the pollutants from the two primary sources of coal-fired power plants and vehicle emissions. Although conventional Particulate Emission Control Devices (PECD) such as electrostatic precipitators in Chinese coal-fired power plants are generally effective for large particles, most of them may not have high collection efficiency of PM2.5. Baghouse filtration is gradually incorporated into the PECD to increase the PM2.5 collection efficiency. By adopting stringent vehicle emissions standard such as Euro 5 and 6, the emissions from vehicles can be gradually reduced over the years. An integrative approach, from collaboration among academia, government, and industries, can effectively manage and mitigate the PM2.s p 展开更多
关键词 PM2.5 in ChinaAtmospheric particle size distributionPM2.5 samplingChemical composition of PM2.sSource apportionment modelsPM2.5 health impactPM2.s mitigationCoal-fired power plantParticle emission control devices (PECD)Baghouse filtrationIntegrative approach
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基于智能软开关的智能配电网柔性互联技术及展望 被引量:176
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作者 王成山 宋关羽 +3 位作者 李鹏 于浩 赵金利 吴建中 《电力系统自动化》 EI CSCD 北大核心 2016年第22期168-175,共8页
以智能软开关(SOP)为基础的柔性互联技术将给传统的配电系统建设及运行方式带来巨大变革。文中围绕以SOP为核心的智能配电网柔性互联问题,对柔性互联技术理念、特征与优势进行了详细阐述,对未来SOP在智能配电网中的典型应用场景进行了分... 以智能软开关(SOP)为基础的柔性互联技术将给传统的配电系统建设及运行方式带来巨大变革。文中围绕以SOP为核心的智能配电网柔性互联问题,对柔性互联技术理念、特征与优势进行了详细阐述,对未来SOP在智能配电网中的典型应用场景进行了分析,并分别面向运行优化、故障恢复、优化配置、装备实现等关键技术环节,对基于SOP的智能配电网柔性互联技术研究与发展进行了展望。 展开更多
关键词 智能配电网 智能软开关 柔性互联 规划 运行
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The first offshore natural gas hydrate production test in South China Sea 被引量:172
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作者 Jin-fa Li Jian-liang Ye +13 位作者 Xu-wen Qin Hai-jun Qiu Neng-you Wu Hai-long Lu Wen-wei Xie Jing-an Lu Fei Peng Zhen-qiang Xu Cheng Lu Zeng-gui Kuang Jian-gong Wei Qian-yong Liang Hong-feng Lu Bei-bei Kou 《China Geology》 2018年第1期5-16,共12页
Natural gas hydrates (NGH)is one of key future clean energy resources.Its industrialized development will help remit the huge demand of global natural gas,relieve the increasing pressure of the environment, and play a... Natural gas hydrates (NGH)is one of key future clean energy resources.Its industrialized development will help remit the huge demand of global natural gas,relieve the increasing pressure of the environment, and play a vital role in the green sustainable growth of human societies.Based on nearly two decades' studying on the reservoir characteristics in the South China Sea (SCS)and the knowledge of reservoir system,the China Geological Survey (CGS)conducted the first production test on an optimal target selected in Shenhu area SCS in 2017.Guided by the "three-phase control"exploitation theory which focused on formation stabilization,technologies such as formation fluid extraction,well drilling and completing, reservoir stimulating,sand controlling,environmental monitoring,monitoring and preventing of secondary formation of hydrates were applied.The test lasted for 60 days from May 10^th when starting to pump, drop pressure and ignite to well killing on July 9^th,with gas production of 3.09×10^5 m^3 in total,which is a world record with the longest continuous duration of gas production and maximal gas yield.This successful test brings a significant breakthrough on safety control of NGH production. 展开更多
关键词 Natural gas HYDRATE (NGH) Production test Shenhu area SOUTH Chma SEA (SCS)
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Spatial patterns and driving forces of land use change in China during the early 21st century 被引量:171
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作者 LIU Jiyuan ZHANG Zengxiang +8 位作者 XU Xinliang KUANG Wenhui ZHOU Wancun ZHANG Shuwen LI Rendong YAN Changzhen YU Dongsheng WU Shixin JIANG Nan 《Journal of Geographical Sciences》 SCIE CSCD 2010年第4期483-494,共12页
Land use and land cover change as the core of coupled human-environment systems has become a potential field of land change science (LCS) in the study of global environmental change. Based on remotely sensed data of... Land use and land cover change as the core of coupled human-environment systems has become a potential field of land change science (LCS) in the study of global environmental change. Based on remotely sensed data of land use change with a spatial resolution of 1 km × 1 km on national scale among every 5 years, this paper designed a new dynamic regionalization according to the comprehensive characteristics of land use change including regional differentiation, physical, economic, and macro-policy factors as well. Spatial pattern of land use change and its driving forces were investigated in China in the early 21 st century. To sum up, land use change pattern of this period was characterized by rapid changes in the whole country. Over the agricultural zones, e.g., Huang-Huai-Hai Plain, the southeast coastal areas and Sichuan Basin, a great proportion of fine arable land were engrossed owing to considerable expansion of the built-up and residential areas, resulting in decrease of paddy land area in southern China. The development of oasis agriculture in Northwest China and the reclamation in Northeast China led to a slight increase in arable land area in northern China. Due to the "Grain for Green" policy, forest area was significantly increased in the middle and western developing regions, where the vegetation coverage was substantially enlarged, likewise. This paper argued the main driving forces as the implementation of the strategy on land use and regional development, such as policies of "Western Development", "Revitalization of Northeast", coupled with rapidly economic development during this period. 展开更多
关键词 land use change spatial pattern driving forces the early 21st century China
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黄精药理作用研究进展 被引量:165
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作者 赵文莉 赵晔 Yiider Tseng 《中草药》 CAS CSCD 北大核心 2018年第18期4439-4445,共7页
黄精为我国常用传统中药,在长江以南大部分地区广泛分布,具有补益肝肾、延年益寿等作用,是自古以来的道家养生圣药。因其含有多糖、皂苷、黄酮、木脂素、氨基酸、醌类化合物、维生素、生物碱及多种微量元素等成分,从而具有较高的药用价... 黄精为我国常用传统中药,在长江以南大部分地区广泛分布,具有补益肝肾、延年益寿等作用,是自古以来的道家养生圣药。因其含有多糖、皂苷、黄酮、木脂素、氨基酸、醌类化合物、维生素、生物碱及多种微量元素等成分,从而具有较高的药用价值和营养价值,国内各研究机构对其进行了较深入的研究,国外对其仍处于初步研究阶段。目前实验研究主要集中在黄精多糖、黄精醇、黄精皂苷提取物或黄精水提物上,以动物实验或单方和复方制剂的临床研究为主。其多种黄精制剂已广泛应用于临床,如黄精口服液、黄精茶、苁蓉精颗粒、黄精赞育胶囊、黄精精油眼罩等,发挥着不同的效用。查阅有关黄精的研究文献,对其药理作用进行全面的综合分析,多角度总结其效用价值,为黄精的深入开发与应用提供参考。 展开更多
关键词 黄精 黄精多糖 黄精提取物 细胞损伤 抗氧化
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不同施肥处理对土壤水稳定性团聚体及有机碳分布的影响 被引量:152
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作者 刘恩科 赵秉强 +3 位作者 梅旭荣 HWAT Bing-So 李秀英 李娟 《生态学报》 CAS CSCD 北大核心 2010年第4期1035-1041,共7页
以国家褐潮土16 a的长期肥料试验为平台(北京昌平),研究长期不同施肥对耕层土壤水稳定性团聚体及其有机碳的影响。主要研究结果:与耕种农田土壤相比,长期撂荒(CK0)可以提高水稳定性大团聚体的含量及其有机碳含量和储量。而农田耕作后,... 以国家褐潮土16 a的长期肥料试验为平台(北京昌平),研究长期不同施肥对耕层土壤水稳定性团聚体及其有机碳的影响。主要研究结果:与耕种农田土壤相比,长期撂荒(CK0)可以提高水稳定性大团聚体的含量及其有机碳含量和储量。而农田耕作后,破坏了水稳性大团聚体,相应地增加水稳性微团聚体的含量。与长期不施肥种植作物(CK)相比,长期施氮磷钾肥(NPK)、氮磷钾配施有机肥(NPKM)和氮磷钾秸秆还田(NPKS)处理对水稳性团聚体数量分布和平均重量直径(MWD)有显著影响,其中对>2mm和0.25 2mm水稳性大团聚体的促进作用最明显,说明施肥处理增加的新碳主要向0.25 2mm和>2mm团聚体富集。在不同水平水稳性团聚体中,>2mm和0.25 2mm两个级别的水稳性大团聚体有机碳的含量显著高于0.0530.25mm和<0.053mm水稳性微团聚体。化肥与有机肥配施(NPKM)处理可提高水稳性大团聚体含量,改善土壤团聚体的结构。长期小麦-玉米→小麦-大豆复种轮作并施氮磷钾化肥的处理(NPKF)各级团聚体中有机碳的含量高于长期小麦-玉米轮作并施氮磷钾化肥的处理(NPK)。 展开更多
关键词 长期肥料试验 水稳定性团聚体 有机碳 碳储量
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Intelligent Manufacturing in the Context of Industry 4.0: A Review 被引量:155
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作者 Ray Y. Zhong Xun Xu +1 位作者 Eberhard Klotz Stephen T. Newman 《Engineering》 SCIE EI 2017年第5期616-630,共15页
Our next generation of industry-lndustry 4.0-holds the promise of increased flexibility in manufacturing, along with mass customization, better quality, and improved productivity. It thus enables companies to cope wit... Our next generation of industry-lndustry 4.0-holds the promise of increased flexibility in manufacturing, along with mass customization, better quality, and improved productivity. It thus enables companies to cope with the challenges of producing increasingly individualized products with a short lead-time to market and higher quality. Intelligent manufacturing plays an important role in Industry 4.0. Typical resources are converted into intelligent objects so that they are able to sense, act, and behave within a smart environment. In order to fully understand intelligent manufacturing in the context of Industry 4.0, this paper provides a comprehensive review of associated topics such as intelligent manufacturing, Internet of Things (IoT)- enabled manufacturing, and cloud manufacturing. Similarities and differences in these topics are highlighted based on our analysis. We also review key technologies such as the loT, cyber-physical systems (CPSs), cloud computing, big data analytics (BDA), and information and communications technology (ICT) that are used to enable intelligent manufacturing. Next, we describe worldwide movements in intelligent manufacturing, including governmental strategic plans from different countries and strategic plans from major international companies in the European Union, United States, Japan, and China. Finally, we present current challenges and future research directions. The concepts discussed in this paper will spark new ideas in the effort to realize the much-anticipated Fourth Industrial Revolution. 展开更多
关键词 Intelligent manufacturing Industry 4.0 Internet of Things Manufacturing systems Cloud manufacturing Cyber-physical system
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Pyroptosis: mechanisms and diseases 被引量:150
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作者 Pian Yu Xu Zhang +3 位作者 Nian Liu Ling Tang Cong Peng Xiang Chen 《Signal Transduction and Targeted Therapy》 SCIE CSCD 2021年第4期1233-1253,共21页
Currently,pyroptosis has received more and more attention because of its association with innate immunity and disease.The research scope of pyroptosis has expanded with the discovery of the gasdermin family.A great de... Currently,pyroptosis has received more and more attention because of its association with innate immunity and disease.The research scope of pyroptosis has expanded with the discovery of the gasdermin family.A great deal of evidence shows that pyroptosis can affect the development of tumors.The relationship between pyroptosis and tumors is diverse in different tissues and genetic backgrounds.In this review,we provide basic knowledge of pyroptosis,explain the relationship between pyroptosis and tumors,and focus on the significance of pyroptosis in tumor treatment.In addition,we further summarize the possibility of pyroptosis as a potential tumor treatment strategy and describe the side effects of radiotherapy and chemotherapy caused by pyroptosis.In brief,pyroptosis is a double-edged sword for tumors.The rational use of this dual effect will help us further explore the formation and development of tumors,and provide ideas for patients to develop new drugs based on pyroptosis. 展开更多
关键词 IMMUNITY DRUGS CHEMOTHERAPY
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The origin, transmission and clinical therapies on coronavirus disease 2019(COVID-19) outbreak——an update on the status 被引量:149
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作者 Yan-Rong Guo Qing-Dong Cao +6 位作者 Zhong-Si Hong Yuan-Yang Tan Shou-Deng Chen Hong-Jun Jin Kai-Sen Tan De-Yun Wang Yan Yan 《Military Medical Research》 SCIE CAS CSCD 2020年第1期93-103,共11页
An acute respiratory disease,caused by a novel coronavirus(SARS-CoV-2,previously known as 2019-nCoV),the coronavirus disease 2019(COVID-19)has spread throughout China and received worldwide attention.On 30 January 202... An acute respiratory disease,caused by a novel coronavirus(SARS-CoV-2,previously known as 2019-nCoV),the coronavirus disease 2019(COVID-19)has spread throughout China and received worldwide attention.On 30 January 2020,World Health Organization(WHO)officially declared the COVID-19 epidemic as a public health emergency of international concern.The emergence of SARS-CoV-2,since the severe acute respiratory syndrome coronavirus(SARSCoV)in 2002 and Middle East respiratory syndrome coronavirus(MERS-CoV)in 2012,marked the third introduction of a highly pathogenic and large-scale epidemic coronavirus into the human population in the twenty-first century.As of 1 March 2020,a total of 87,137 confirmed cases globally,79,968 confirmed in China and 7169 outside of China,with 2977 deaths(3.4%)had been reported by WHO.Meanwhile,several independent research groups have identified that SARS-CoV-2 belongs toβ-coronavirus,with highly identical genome to bat coronavirus,pointing to bat as the natural host.The novel coronavirus uses the same receptor,angiotensin-converting enzyme 2(ACE2)as that for SARS-CoV,and mainly spreads through the respiratory tract.Importantly,increasingly evidence showed sustained human-tohuman transmission,along with many exported cases across the globe.The clinical symptoms of COVID-19 patients include fever,cough,fatigue and a small population of patients appeared gastrointestinal infection symptoms.The elderly and people with underlying diseases are susceptible to infection and prone to serious outcomes,which may be associated with acute respiratory distress syndrome(ARDS)and cytokine storm.Currently,there are few specific antiviral strategies,but several potent candidates of antivirals and repurposed drugs are under urgent investigation.In this review,we summarized the latest research progress of the epidemiology,pathogenesis,and clinical characteristics of COVID-19,and discussed the current treatment and scientific advancements to combat the epidemic novel coronavirus. 展开更多
关键词 Clinical characteristics Coronavirus disease 2019(COVID-19) ORIGIN SARS-CoV-2 Therapy TRANSMISSION
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