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风力发电机接闪系统失效风险定量评估方法研究

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中国电机工程学报 2019年第12期39卷 3551-3560页

作者：于万水李庆民张敏昊郭子炘刘亮 Siew Wah Hoon 王健电力系统国家重点实验室(华北电力大学) 北京市昌平区102206 国网冀北电力有限公司电力科学研究院北京市西城区100045 思克莱德大学 Glasgow G1 1XQ UK

雷害问题严重影响风机的正常运行,但针对风机接闪系统的失效风险,目前鲜有定量的分析和评估方法。基于先导发展物理模型,提出风机接闪系统雷击屏蔽失效率的定义和计算方法,并通过叶片雷击模拟实验验证了方法的有效性。比较分析了不同接... 详细信息

雷害问题严重影响风机的正常运行,但针对风机接闪系统的失效风险,目前鲜有定量的分析和评估方法。基于先导发展物理模型,提出风机接闪系统雷击屏蔽失效率的定义和计算方法,并通过叶片雷击模拟实验验证了方法的有效性。比较分析了不同接闪系统型式叶片的雷击屏蔽失效率,并考虑了风机旋转角度和海洋盐雾附着对雷击屏蔽失效率的影响。分析表明,相比于接闪器–引下线结构型式和叶尖包覆铜网型式,采用主梁包覆铜网型式的叶片雷击屏蔽失效率最小,但综合考虑经济性和易维护性,推荐采用叶尖包覆铜网的接闪系统型式。提出的定量分析方法可为风机叶片接闪系统的优化设计和失效风险评估提供依据。

关键词：雷击屏蔽失效率风力发电机接闪系统盐雾附着长间隙放电

Genomes reveal selective sweeps in kiang and donkey for high-altitude adaptation

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Zoological Research 2021年第4期42卷 450-460页

作者： Lin Zeng He-Qun Liu Xiao-Long Tu Chang-Mian Ji Xiao Gou Ali Esmailizadeh Sheng Wang Ming-Shan Wang Ming-Cheng Wang Xiao-Long Li Hadi Charati Adeniyi CAdeola Rahamon Akinyele Moshood Adedokun Olatunbosun Oladipo Sunday Charles Olaogun Oscar JSanke Mangbon Godwin F Sheila Cecily Ommeh Bernard Agwanda Jacqueline Kasiiti Lichoti Jian-Lin Han Hong-Kun Zheng Chang-Fa Wang Ya-Ping Zhang Laurent A.F.Frantz Dong-Dong Wu State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650223China Hainan Key Laboratory for Biosafety Monitoring and Molecular Breeding in Off-Season Reproduction Regions Institute of Tropical Bioscience and BiotechnologyChinese Academy of Tropical Agricultural SciencesHaikouHainan 571101China College of Animal Science and Technology Yunnan Agricultural UniversityKunmingYunnan 650201China department of Animal Science Faculty of AgricultureShahid Bahonar University of KermanKermanPB 76169-133Iran Kunming College of Life Science University of Chinese Academy of SciencesKunmingYunnan 650204China Sino-Africa Joint Research Center Chinese Academy of SciencesKunmingYunnan 650223China Center for Excellence in Animal Evolution and Genetics Chinese Academy of SciencesKunmingYunnan 650223China Institute of Three-River-Source National Park Chinese Academy of SciencesXiningQinghai 810008China School of Biological and Chemical Sciences Queen Mary University of LondonLondon E14NSUK department of Genetics Albert Einstein College of MedicineBronxNew YorkNY 10461USA Annoroad Gene Tech.(Beijing)Co. Ltd.Beijing 100176China State Key Laboratory of Genetic Resources and Evolution Yunnan Laboratory of Molecular Biology of Domestic AnimalsGermplasm Bank of Wild SpeciesKunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650223China department of Veterinary Medicine University of IbadanIbadan 200284Nigeria Federal College of Animal Health and Production Technology Moor-PlantationIbadan 234102Nigeria Taraba State Ministry of Agriculture and Natural Resources Jalingo 660221Nigeria Division of Veterinary Office Serti 663101Nigeria Institute For Biotechnology Research Jomo Kenyatta University of Agriculture and Technology Nairobi 62000-00200Kenya department of Zoology National Museums of KenyaNairobi 40658-00100Kenya State department of Livestock Ministry of AgricultureLivestockFisheries and IrrigationN

Over the last several hundred years,donkeys have adapted to high-altitude conditions on the Tibetan ***,the kiang,a closely related equid species,also inhabits this *** reports have demonstrated the importance of specific genes and adaptive introgression in divergent lineages for adaptation to hypoxic conditions on the Tibetan ***,we assessed whether donkeys and kiangs adapted to the Tibetan Plateau via the same or different biological pathways and whether adaptive introgression has *** assembled a de novo genome from a kiang individual and analyzed the genomes of five kiangs and 93 donkeys(including 24 from the Tibetan Plateau).Our analyses suggested the existence of a strong hard selective sweep at the EPAS1 locus in *** Tibetan donkeys,however,another gene,i.e.,EGLN1,was likely involved in their adaptation to high *** addition,admixture analysis found no evidence for interspecific gene flow between kiangs and Tibetan *** findings indicate that despite the short evolutionary time scale since the arrival of donkeys on the Tibetan Plateau,as well as the existence of a closely related species already adapted to hypoxia,Tibetan donkeys did not acquire adaptation via admixture but instead evolved adaptations via a different biological pathway.

关键词： Kiang Donkey High altitude Adaptation Selection

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基于激光视觉的螺旋焊管内外焊焊缝跟踪系统

焊管 2007年第4期30卷 41-43页

作者：林三宝秦克礼 ZHAO Jing R J Beattie 哈尔滨工业大学现代焊接生产技术国家重点实验室哈尔滨150001 宝鸡石油钢管有限责任公司陕西宝鸡721008 Meta Vision Systems ltd UK Oxford OX29 4TH

介绍了一种基于激光视觉的螺旋焊管内外焊焊缝跟踪系统,该系统采用结构激光+CCD作为传感器,所采集的激光条纹图像通过PC机进行图像处理和模式识别,再通过可编程控制器(PLC)计算偏差的数据,驱动精密十字滑架,同时调整内焊和外焊焊枪。系... 详细信息

介绍了一种基于激光视觉的螺旋焊管内外焊焊缝跟踪系统,该系统采用结构激光+CCD作为传感器,所采集的激光条纹图像通过PC机进行图像处理和模式识别,再通过可编程控制器(PLC)计算偏差的数据,驱动精密十字滑架,同时调整内焊和外焊焊枪。系统的跟踪精度小于0.5mm。通过在国内多家企业的应用实践证明,该系统的使用能够提高焊缝质量,降低废品率和工人的劳动强度。

关键词：螺旋焊管埋弧焊焊缝跟踪激光视觉传感器

Neuroprotectants attenuate hypobaric hypoxia-induced brain injuries in cynomolgus monkeys

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Zoological Research 2020年第1期41卷 3-19页

作者： Pei Zhang Jie-Si Chen Qi-Ye Li Long-Xiang Sheng Yi-Xing Gao Bing-Zheng Lu Wen-Bo Zhu Xiao-Yu Zhan Yuan Li Zhi-Bing Yuan Gang Xu Bi-Tao Qiu Min Yan Chun-Xue Guo You-Qiong Wang Yi-Jun Huang Jing-Xia Zhang Fu-Yu Liu Zhong-Wei Tang Sui-Zhen Lin David NCooper Huan-Ming Yang Jian Wang Yu-Qi Gao Wei Yin Guo-Jie Zhang Guang-Mei Yan State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650223China BGI-Shenzhen ShenzhenGuangdong 518083China Section for Ecology and Evolution Department of BiologyUniversity of CopenhagenCopenhagen DK-2100Denmark department of Pharmacology Zhongshan School of MedicineSun Yat-Sen UniversityGuangzhouGuangdong 510080China Institute of Medicine and Hygienic Equipment for High Altitude Region College of High Altitude Military MedicineThird Military Medical UniversityChongqing 400038China Key Laboratory of High Altitude Medicine of People's Liberation Army Chongqing 400038China Key Laboratory of High Altitude Environmental Medicine Third Military Medical UniversityMinistry of EducationChongqing 400038China School of Pharmaceutical Sciences Sun Yat-Sen UniversityGuangzhouGuangdong 510006China Guangzhou Cellprotek Pharmaceutical Co.ltd. GuangzhouGuangdong 510663China Institute of Medical Genetics School of MedicineCardiff UniversityCardiff CF144XNUK James D.Watson Institute of Genome Sciences HangzhouZhejiang 310058China department of Biochemistry Zhongshan School of MedicineSun Yat-Sen UniversityGuangzhouGuangdong 510080China Center for Excellence in Animal Evolution and Genetics Chinese Academy of SciencesKunmingYunnan 650223China China National Genebank BGI-ShenzhenShenzhenGuangdong 518120China

Hypobaric hypoxia (HH) exposure can cause serious brain injury as well as life-threatening cerebral edema in severe cases. Previous studies on the mechanisms of HH-induced brain injury have been conducted primarily using non-primate animal models that are genetically distant to humans, thus hindering the development of disease treatment. Here, we report that cynomolgus monkeys (Macaca fascicularis) exposed to acute HH developed human-like HH syndrome involving severe brain injury and abnormal behavior. Transcriptome profiling of white blood cells and brain tissue from monkeys exposed to increasing altitude revealed the central role of the HIF-1 and other novel signaling pathways, such as the vitamin D receptor (VDR) signaling pathway, in co-regulating HH-induced inflammation processes. We also observed profound transcriptomic alterations in brains after exposure to acute HH, including the activation of angiogenesis and impairment of aerobic respiration and protein folding processes, which likely underlie the pathological effects of HH-induced brain injury. Administration of progesterone (PROG) and steroid neuroprotectant 5α-androst-3β,5,6β-triol (TRIOL) significantly attenuated brain injuries and rescued the transcriptomic changes induced by acute HH. Functional investigation of the affected genes suggested that these two neuroprotectants protect the brain by targeting different pathways, with PROG enhancing erythropoiesis and TRIOL suppressing glutamate-induced excitotoxicity. Thus, this study advances our understanding of the pathology induced by acute HH and provides potential compounds for the development of neuroprotectant drugs for therapeutic treatment.

关键词： Acute hypobaric hypoxia Cynomolgus monkeys Brain injury Neuroprotectant Gene regulatory networks

雷击电弧气爆效应对风机的损伤机制与叶片优化设计

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中国电机工程学报 2020年第8期40卷 2705-2714页

作者：李宏博张敏昊李庆民于万水郭子炘 Siew Wah Hoon 新能源电力系统国家重点实验室(华北电力大学) 北京市昌平区102206 内蒙古电力(集团)有限责任公司内蒙古自治区呼和浩特市010020 思克莱德大学 Glasgow G11XQ UK

风机叶片雷击灾害事故频发,而雷击电弧对叶片气爆损伤机制尚不清晰,传统实验手段难以测量损伤过程中的细节参数。因此,以实际风机叶片为基础,搭建雷击电弧路径几何模型。基于磁流体动力学理论,利用有限元仿真软件COMSOL分别探究温度和... 详细信息

风机叶片雷击灾害事故频发,而雷击电弧对叶片气爆损伤机制尚不清晰,传统实验手段难以测量损伤过程中的细节参数。因此,以实际风机叶片为基础,搭建雷击电弧路径几何模型。基于磁流体动力学理论,利用有限元仿真软件COMSOL分别探究温度和压力在叶片内部的分布情况。进一步,对比不同引弧方式和雷击点位置对叶片材料碳化程度和后缘压力最大值的影响作用。发现叶片在遭受雷击后,雷击点的温度先迅速升高至最大值,然后缓慢降低,高温区域主要分布在雷击电弧周围。叶片后缘的压力先增加至峰值,然后呈现震荡衰减趋势。高压力区域先分布在右侧腹板与后缘之间,后逐渐向整个叶腔内扩散。叶片材料碳化程度和后缘压力最大值与已有文献的实验结果较为吻合,验证了仿真模型的正确性。当雷击点靠近叶尖时,叶片材料碳化程度和后缘压力最大值呈现上升趋势,当引下线布置于主梁时,上述两者均低于引下线布置于右侧腹板的情况。最后,从防雷角度出发,建议将引下线布置于主梁,同时使用环氧树脂将叶片后缘粘接处浇铸成半径为30mm的圆角。

关键词：风机叶片雷击防护损伤机制优化设计

Highly spatial and temporal bottom-up vehicle emission characterization and its control in a typical ecology-preservation area

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Eco-Environment & Health 2022年第3期1卷 156-164页

作者： Pengju Bie Fanyuan deng Bi Chen Li Wang Fan Yang Jianguo Zhou Huan Liu Kebin He State Key Joint Laboratory of ESPC State Environmental Protection Key Laboratory of Sources and Control of Air Pollution ComplexSchool of EnvironmentInternational Joint Laboratory on Low Carbon Clean Energy InnovationTsinghua UniversityBeijing 100084China Technique Center of Kweichow Moutai Co.ltd. Renhuai 564501China

The Chishui River Valley is a microscale ecology-preservation area with industrial *** significance of evaluating vehicular emissions has been gradually highlighted with the rapid development of the local transportation and tourism *** study provides the first estimates based on both bottom-up and top-down *** annual total emissions of CO,NOx,hydrocarbons(HC),PM10,and PM2.5 in 2019 were 347.8,189.6,46.3,6.9,and 6.3 Mg,*** contributed the most(55%)to the NOx emissions,followed by heavy-duty passenger vehicles(26%).In contrast,light-duty passenger vehicles and motorcycles generated 75%of the HC *** superior accuracy of highly spatial and temporal bottom-up estimates versus top-down estimates is validated by the similar variation trends of hourly emission intensities and enhanced concentrations relative to background observations for both NOx and CO,with Pearson correlation coefficients between the intensities and concentrations ranging from 0.79 to *** HC emissions peaked in 2013,followed by a sharp decline in 2014 and a continuous rise since then,whereas NOx emissions have kept increasing since *** indicated the necessity and urgency of effective vehicular emission *** on scenario analysis,traffic restrictions combined with upgrading the emission standards of admitted vehicles will possess huge emission reduction *** recommendations about establishing a low emission zone in the valley and supporting policies were introduced.

关键词： Vehicle Emission Bottom-up method Ecology-preservation Mitigation Low-emission zone

维普期刊数据库评论

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干辣椒风味物质气相色谱及质谱方法的研究

辣椒杂志 2007年第1期5卷 41-47页

作者： Saskia van Ruth Elena Boscaini Dagmar Mayr Jonathan Pugh Maarten Posthumus 刘蓉刘志敏食品学院食品科学与营养专业科克大学 Institut für Ionenphysik利奥波德-费的南大学因思布鲁克市奥地利256020 应用研究实验室 MicromassUK.Ltd. 有机化学实验室食品学院Wageningen大学研究中心不详

用嗅觉测量法-气相色谱联用(GC-O),火焰离子检测器-气相色谱联用(GC-FID),质谱-气相色谱联用(GC-MS)三种气相色谱检测方法和常压化学离子化飞行时间质谱(APCI-TOFMS),质子传递反应质谱(PTR-MS)两种直接质谱检测方法来比较测定干辣椒中... 详细信息

用嗅觉测量法-气相色谱联用(GC-O),火焰离子检测器-气相色谱联用(GC-FID),质谱-气相色谱联用(GC-MS)三种气相色谱检测方法和常压化学离子化飞行时间质谱(APCI-TOFMS),质子传递反应质谱(PTR-MS)两种直接质谱检测方法来比较测定干辣椒中的挥发性香味成分。干辣椒的挥发性香味成分的大体描述最后由感官评定来确定。三种较显著的风味分别是:辣椒味、煮熟蔬菜味和青草味。用气质联用顶空分析法共有63种挥发性香味成分被分离出来。而嗅觉测量法-气相色谱联用(GC-O)认为其中的11种成分决定了辣椒的香味活跃程度。在所有的方法中普遍认为:3-甲基正丁醛是最活跃的香味成份,其次是2-甲基正丁醛。确定挥发性香味成分的多少主要是受测定方法的影响。色谱方法之间有很强的相关性(ρ=0.946)。直接质谱法相关性不显著(ρ=0.613)。经过不同方法的分析,我们发现,用GC-MS,GC-FID和PTR-MS三种方法检测出的挥发性香味成分并没有显著的不同,显著性的差异主要存在于PCI-TOFMS法和其工艺的不同(P<0.01).(Int J Mass Spectrom223-224(2003)55-65)

关键词： APCI-TOFMS GC-FID GC-MS GC-O PTR-MS

Extreme fire weather is the major driver of severe bushfires in southeast Australia

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Science Bulletin 2022年第6期67卷 655-664,M0004页

作者： Bin Wang Allan C.Spessa Puyu Feng Xin Hou Chao Yue Jing-Jia Luo Philippe Ciais Cathy Waters Annette Cowie Rachael H.Nolan Tadas Nikonovas Huidong Jin Henry Walshaw Jinghua Wei Xiaowei Guo de Li Liu Qiang Yu State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F UniversityYangling 712100China New South Wales department of Primary Industries Wagga Wagga Agricultural InstituteWagga Wagga 2650Australia department of Geography College of ScienceSwansea UniversitySingleton ParkSwansea SA28PPUK College of Land Science and Technology China Agricultural UniversityBeijing 100193China College of Natural Resources and Environment Northwest A&F UniversityYangling 712100China Institute for Climate and Application Research(ICAR)/Key Laboratory of Meteorological Disaster of Ministry of Education(KLME) Nanjing University of Information Science and TechnologyNanjing 210044China Laboratoire des Sciences du Climat et de l'Environnement CEA-CNRS-UVSQGif sur Yvette F-91191France New South Wales department of Primary Industries Dubbo 2830Australia New South Wales department of Primary Industries Armidale 2351Australia School of Environmental and Rural Science University of New EnglandArmidale 2351Australia Hawkesbury Institute for the Environment Western Sydney UniversityPenrith 2751Australia CSIRO Data61 Canberra 2601Australia Python Charmers Pty ltd Hawthorn 3122Australia Key Laboratory of Adaptation and Evolution of Plateau Biota Northwest Institute of Plateau BiologyChinese Academy of SciencesXining 810008China Climate Change Research Centre University of New South WalesSydney 2052Australia College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China

In Australia,the proportion of forest area that burns in a typical fire season is less than for other vegetation ***,the 2019-2020 austral spring-summer was an exception,with over four times the previous maximum area burnt in southeast Australian temperate *** forest fires have extensive socio-economic,human health,greenhouse gas emissions,and biodiversity impacts due to high fire intensities.A robust model that identifies driving factors of forest fires and relates impact thresholds to fire activity at regional scales would help land managers and fire-fighting agencies prepare for potentially hazardous fire in ***,we developed a machine-learning diagnostic model to quantify nonlinear relationships between monthly burnt area and biophysical factors in southeast Australian forests for 2001-2020 on a 0.25°grid based on several biophysical parameters,notably fire weather and vegetation *** model explained over 80%of the variation in the burnt *** identified that burnt area dynamics in southeast Australian forest were primarily controlled by extreme fire weather,which mainly linked to fluctuations in the Southern Annular Mode(SAM)and Indian Ocean Dipole(IOD),with a relatively smaller contribution from the central Pacific El Niño Southern Oscillation(ENSO).Our fire diagnostic model and the non-linear relationships between burnt area and environmental covariates can provide useful guidance to decision-makers who manage preparations for an upcoming fire season,and model developers working on improved early warning systems for forest fires.

关键词： Remote sensing Forest fires Climate drivers Burnt area modelling Machine learning Southeast Australia

SEMiX and SKYPER an Intelligent IGBT Module with Adaptable Driver

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电力电子 2004年第5期2卷 24-29页

作者： MartinFreyberg MarkusHermwille uk-SongHong JensLi SemikronInternationalDr.FritzMartinGmbh&Co.KGSigmundstr.200.90431Nuremberg.Germany SemikronCo.ltd.137-7.Sosahon-3Dong.Sosa-BuBucheon-City.422-233

Modern power converter designs need compact IGBT modules with simple interfaces for costefficient power *** overall *** AC and DC terminals on eaeh side,driver access on top are recent market requirements for modern power *** leads to the birth of SEMiX-a module platform with the right answer to these *** paper highlights also a new driver solution for modules-SKYPER-a simple add-on gate driver with basic driving and protection *** adaptation to modules-in this article through an example with SEMiX-is tested *** and SKYPER behave like an IPM but offer more flexibilitv to control switching *** a convenient building block for modular inverter solutions.

关键词：逆变器 IGBT模型自适应驱动器 SEMiX SKYPER