检索结果-南通市图书馆

In situ high-pressure wide-angle hard x-ray photon correlation spectroscopy:A versatile tool probing atomic dynamics of extreme condition matter

在线全文

学校读者我要写书评

暂无评论

Matter and Radiation at extremes 2023年第2期8卷 76-78页

作者： Qiaoshi Zeng Center for High Pressure Science and Technology Advanced Research PudongShanghai 201203People’s Republic of China Shanghai Key Lab of Material Frontiers Research in extreme Environments(MFree) Shanghai Advanced Research in Physical Sciences(SHARPS)PudongShanghai 201203People’s Republic of China

With the advent of new synchrotron radiation x-ray sources that provide a significantly enhanced coherent flux,high-energy x-ray photon correlation spectroscopy measurements can be performed on materials in a diamond anvil *** information on atomic dynamics that was previously inaccessible can be obtained for various novel phenomena emerging under extreme *** article discusses the importance,feasibility,and experimental details of this technique,as well as the opportunities that it offers to address critical scientific challenges.

关键词： extreme dynamics spectroscopy

Impact of the Horizontal Heat Flux in the Mixed Layer on an extreme Heat Event in North China:A Case Study

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 2019年第2期36卷 133-142页

作者： Ying NA Riyu LU Bing LU Min CHEN Shiguang MIAO State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences College of Earth and Planetary Sciences University of the Chinese Academy of Sciences Institute of Urban Meteorology China Meteorological Administration

extreme heat over the North China Plain is typically induced by anomalous descending flows associated with anticyclonic circulation anomalies. However, an extreme heat event that happened in the North China Plain region on 12–13 July 2015,with maximum temperature higher than 40℃ at some stations, was characterized by only a weak simultaneous appearance of an anomalous anticyclone and descending flow, suggesting that some other factor(s) may have induced this heat event. In this study, we used the forecast data produced by the Beijing Rapid Updated Cycling operational forecast system, which predicted the heat event well, to investigate the formation mechanism of this extreme heat event. We calculated the cumulative heat in the mixed-layer air column of North China to represent the change in surface air temperature. The cumulative heat was composed of sensible heat flux from the ground surface and the horizontal heat flux convergence. The results indicated that the horizontal heat flux in the mixed layer played a crucial role in the temporal and spatial distribution of high *** horizontal heat flux was found to be induced by distinct distributions of air temperatures and horizontal winds at low levels during the two days, implying a complexity of the low-level atmosphere in causing the extreme heat.

关键词： extreme heat North China Plain horizontal heat flux sensible heat flux warm advection

extreme Cities and Isotropic Territories: Scenarios and Projects Arising from the Environmental Emergency of the Central Veneto Città Diffusa

在线全文

学校读者我要写书评

暂无评论

International Journal of Disaster Risk Science 2012年第1期3卷 11-22页

作者： Lorenzo Fabian Department of Urbanism University IUAV of Venice(Istituto Universitario di Architettura di Venezia)30125 VeniceItaly

In Italy extreme cities and territories occur at the extremities of lagoons,coastlines,and river deltas,in hydraulically reclaimed and hydrogeologically instable areas,and those where the water supply network has been placed underground,channeled into piping,or removed altogether. These areas are now increasingly subject to natural calamities and extreme weather conditions,and the consequences of climate change and the fragility of the more and more impermeable and urbanized land surface are clearly evident. Isotropic territories are characterized by weak hierarchization of infrastructure and settlement. The metropolitan area of Venice,aptly described as a diffuse city(città diffusa),and other diffusely organized territories characterized by settlement dispersion are good examples of this phenomenon. This article reviews recent research at the University IUAV of Venice in a study on climate change and water forms,a project in which the profound relations between water networks,the geological nature of the terrain,forms of urbanization,and energy saving are tested out. The study of the territories of the Venetian metropolitan area provides a series of initial working hypotheses as to how the ongoing environmental emergency can become an opportunity for a development project of the city and the territory,capable of structuring its various parts differently.

关键词： extreme consequences underground

Fabrication of extreme wettability surface for controllable droplet manipulation over a wide temperature range

在线全文

学校读者我要写书评

暂无评论

International Journal of extreme Manufacturing 2022年第4期4卷 246-259页

作者： Chengsong Shu Qitong Su Minghao Li Zhenbin Wang Shaohui Yin Shuai Huang College of Mechanical and Vehicle Engineering Hunan UniversityChangsha 410082People’s Republic of China National Engineering Research Center for High Efficiency Grinding Hunan UniversityChangsha 410082People’s Republic of China

Droplet controllable manipulation over a wide temperature range has promising applications in microelectronic heat dissipation, inkjet printing, and high temperature microfluidic system. However, the fabrication of a platform for controllable droplet manipulation using the methods commonly used in industry remains a tremendously challenge. The popular method of controlling droplets is highly dependent on external energy input and has relatively poor controllability in terms of droplet motion behaviors and manipulation environment, such as distance, velocity, direction and a wide temperature range. Here, we report a facile and industrially applicable method for preparing Al superhydrophobic (S-phobic) surfaces, which enables controlled droplet bouncing, evaporation, and transport over a wide temperature range. Systematic mechanistic studies are also investigated. extreme wettability surfaces were prepared on Al substrate by a composite process of electrochemical mask etching and micro-milling. To investigate the evaporation process and thermal coupling characteristics, controlled evaporation and controlled bouncing of droplet in a wide temperature range were conducted. Based on the evaporation regulation and bouncing mechanism of droplets on an extreme wettability surface, by using Laplace pressure gradients and temperature gradients, we realized controlled transport of droplets with confluence, split-flow, and gravity-resistant transport over a wide temperature range, offering a potential platform for a series of applications, such as new drug candidates and water collection.

关键词： extreme wettability surface superhydrophobic controlled evaporation controlled bouncing controlled transport

Impact of Surface Potential Vorticity Density Forcing over the Tibetan Plateau on the South China extreme Precipitation in January 2008. Part Ⅱ:Numerical Simulation

在线全文

学校读者我要写书评

暂无评论

Journal of Meteorological Research 2019年第3期33卷 416-432页

作者： Jiahui YU Yimin LIU Tingting MA Guoxiong WU State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics (IAP) Chinese Academy of Sciences Beijing 100029 Tianjin Meteorological Service Center Tianjin 300074 College of Earth Science University of Chinese Academy of Sciences Beijing 100049

The surface air convergence on the eastern flank of the Tibetan Plateau (TP) can increase the in situ surface potential vorticity density (PVD). Since the elevated TP intersects with the isentropic surfaces in the lower troposphere, the increased PVD on the eastern flank of TP thus forms a PVD forcing to the intersected isentropic surface in the boundary layer. The influence of surface PVD forcing over the TP on the extreme freezing rain/snow over South China in January 2008 is investigated by using numerical experiments based on the Finite-volume Atmospheric Model of the IAP/LASG (FAMIL). Compared with observations, the simulation results show that, by using a nudging method for assimilating observation data in the initial flow, this model can reasonably reproduce the distribution of precipitation, atmospheric circulation, and PVD propagation over and downstream of the TP during the extreme winter precipitation period. In order to investigate the impact of the increased surface PVD over the TP on the extreme precipitation in South China, a sensitivity experiment with surface PVD reduced over the TP region was performed. Compared with the control experiment, it is found that the precipitation in the TP downstream area, especially in Southeast China, is reduced. The rainband from Guangxi Region to Shandong Province has almost disappeared. In the lower troposphere, the increase of surface PVD over the TP region has generated an anomalous cyclonic circulation over southern China, which plays an important role in increasing southerly wind and the water vapor transport in this area;it also increases the northward negative absolute vorticity advection. In the upper troposphere, the surface PVD generated in eastern TP propagates on isentropic surface along westerly wind and results in positive absolute vorticity advection in the downstream areas. Consequently, due to the development of both ascending motion and water vapor transport in the downstream place of the TP, extre

关键词： extreme weather event Tibetan Plateau potential vorticity density (PVD) surface PVD forcing numerical simulation

Integrated assessment of extreme climate and landuse change impact on sediment yield in a mountainous transboundary watershed of India and Pakistan

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain Science 2020年第3期17卷 624-640页

作者： Muhammad BABUR Sangam SHRESTHA Binod BHATTA Avishek DATTA Hayat ULLAH Civil Engineering Department University of Central Punjab1-Khayaban-e-Jinnah RoadJohar Town Lahore 54770Pakistan Department of Water Engineering and Management School of Engineering and TechnologyAsian Institute of TechnologyPathum Thani 12120Thailand Department of Food Agriculture and BioresourcesSchool of EnvironmentResources and DevelopmentAsian Institute of TechnologyPathum Thani 12120Thailand

Assessment of climate and land use changes impact including extreme events on the sediment yield is vital for water and power stressed countries. Mangla Reservoir is the second-largest reservoir in Pakistan, and its capacity is being reduced due to rapid sedimentation and will be threatened under climate and land use changes. This paper discusses the consequences of climate and land use change on sediment yield at Mangla Dam using General Circulation Models(GCMs), Land Change Modeler(LCM), Soil and Water Assessment Tool(SWAT) model after calibration and *** show that over the historical period temperature is observed to increase by 0.10 o C/decade and forest cover is observed to reduce to the level of only 16% in 2007. Nevertheless, owing to the forest conservation policy, the forest cover raised back to 27% in 2012. Anticipated land use maps by using LCM of 2025, 2050 and 2100 showed that the forest cover will be 33%, 39.2%, and, 53.7%, respectively. All seven GCMs projected the increase in temperature and five GCMs projected an increase in precipitation,however, two GCMs projected a decrease in precipitation. Owing to climate change, land use change and combined impact of climate and land use change on annual sediment yield(2011-2100) may vary from-42.9% to 39.4%, 0% to-27.3% and,-73%to 39.4%, respectively. Under climate change scenarios projected sediment yield is mainly linked with extreme events and is expected to increase with the increase in extreme events. Under land use change scenarios projected sediment yield is mainly linked with the forest cover and is expected to decrease with the increase in forest cover. The results of this study are beneficial for planners, watershed managers and policymakers to mitigate the impacts of climate and land use changes to enhance reservoir life by reducing the sediment yield.

关键词： Climate change and land use changes extreme events Terrset LCM Sediment yield

Lifetime Calculations on Collector Optics from Laser Plasma extreme Ultraviolet Sources with Minimum Mass

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2011年第5期28卷 180-183页

作者： WU Tao WANG Xin-Bing Wuhan National Laboratory for Optoelectronics School of Optoelectronic Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074 School of Science Wuhan Institute of TechnologyWuhan 430074

An ion flux and its kinetic energy spectrum are obtained using a self similar spherically symmetric fluid model of expansion of a collisionless plasma into *** to the ion flux and energy distribution,the collector optical lifetime is estimated by knowledge of the sputtering yield of conventional Mo/Si multilayer coatings for the CO_(2)and Nd:YAG pulsed-laser produced plasmas based on the minimum mass tin droplet target without debris *** results show that the longer wavelength of the CO_(2)laser produced plasma light source is more suitable for extreme ultraviolet lithography than Nd:YAG laser in respect of fast ion debris induced sputtering damage to the collector mirror.

关键词： lithography debris extreme

Influence of the Arctic on the Predictability of Eurasian Winter extreme Weather Events

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 2020年第4期37卷 307-317页

作者： Guokun DAI Mu MU Department of Atmospheric and Oceanic Sciences and Institute of Atmospheric Sciences Fudan UniversityShanghai 200438China

The linkage between the Arctic and midlatitudes has received much attention recently due to the rapidly changing *** investigations have been conducted to reveal the relationship between the Arctic and Eurasian extreme events from the perspective of climatological *** a prediction source for extreme events in Eurasia,Arctic conditions are crucial for extreme event ***,it is urgent to explore the Arctic influence on the predictability of Eurasian extreme events due to the large uncertainties in Arctic *** the sensitivity and nonlinearity of the atmospheric circulations in midlatitude to Arctic conditions,it is necessary to investigate the Arctic influences on Eurasian extreme weather events in case studies at weather time *** studies indicate that only perturbations in specific patterns have fast ***,the conditional nonlinear optimal perturbation approach is recommended for exploring the uncertainties in Arctic initial and boundary conditions and their synergistic effect on Eurasian extreme ***,the mechanism for extreme event formation may differ in different ***,more extreme cases should be investigated to reach robust conclusions.

关键词： Arctic uncertainties Eurasian extreme weather events synergistic effect optimization algorithms

A research progress review on regional extreme events

在线全文

学校读者我要写书评

暂无评论

Advances in Climate Change Research 2018年第3期9卷 161-169页

作者： REN Fu-Min Blair TREWIN Manola BRUNET Pattanaik DUSHMANTA Andreas WALTER Omar BADDOUR Maya KORBER State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China Bureau of Meteorology Melbourne VIC 3001 Australia Centre for Climate Change Department of Geography University Rovira i Virgili Tarragona 43007 Spain Climatic Research Unit School of Environmental Sciences University of East Anglia Norwich NR4 7TJ UK India Meteorological Department New Delhi 110003 India German Meteorological Service (DWD) Offenbach 63067 Germany World Meteorological Organization Geneva 1211 Switzerland

An extreme （weather and climate） event does not only mean that an extreme occurs at a location, but more generally it can impact a certainarea and last a certain period of time, which is defined as a regional extreme event （REE） with a certain impacted area and duration. The conceptof REE has been defined to allow mainly objective assessment of the events without a pre-determined boundary and duration. This paper reviewsthe studies on REEs published during the past 20 years, especially recent years. Mainly in view of methodology, these studies can be divided intothree types studies focusing on spatial simultaneity, studies focusing on temporal persistence, and studies identifying REEs. The methodsidentifying REEs include two kinds, e.g., type-I methods stressing REE＇s temporal persistence within a relatively certain area and type-IImethods focusing on catching a complete REE. Identification methods proposed in this paper could provide valuable information for variouspurposes, such as real-time monitoring, estimating long-term changes, mechanism diagnosis, forecasting study and even attribution *** on REEs is important for objectively defining extreme weather and climate events, which depends on the spatial and temporal scales ofinterest. Such an objective definition will support ongoing climate monitoring and improve the assessment of how regional extreme events havechanged over time.

关键词： extreme (weather and climate) events Regional extreme events Research progress Review