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Advances in Polar Science 2016年第2期27卷 78-89页

作者： AN Meijian douglas a.wiens ZHAO Yue Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China Department of Earth and Planetary Science Washington UniversitySt.LouisMO 63130MissouriUSA

The Gamburtsev Antarctic Mountains Seismic Experiment （GAMSEIS, 2007-2010） was jointly conducted by the United States, China, and Japan during and after the International Polar Year 2007-2008. Broadband seismic stations were deployed across the ice-covered Gamburtsev Subglacial Mountains （GSM） and other previously unexplored areas in the interior of East Antarctica. Using GAMSEIS data, published results not only have revealed the deep structure of Antarctica, but also improved our understanding of the tectonic evolution of Antarctica and the supercontinent Gondwana, and of the relationship between geothermal heat flux and glaciers. This contribution draws together the major findings from recent studies, and also offers further investigation into the relationship between tectonic history and the East Antarctic Ice Sheet. The elevation of the GSM is largely supported by thickened crust, with Moho depths of ~60 km near the crest of the range. The GSM are underlain by thick （〉200 km） and cold continental lithosphere that likely formed after collision of two ancient crustal blocks during the pan-African orogeny. Heat flux results obtained from seismic inversion support a model of ice sheet basal melting that depends more strongly on bedrock topography than on geothermal heat flux, while ice surface and ice thickness are inversely correlated with heat flux.

关键词： GAMSEIS crust lithosphere ice sheet Gondwana International Polar Year

Upper mantle hydration indicated by decreased shear velocity near the Southern Mariana Trench from Rayleigh wave tomography

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Upper mantle hydration indicated by decreased shear velocity...

2020年中国地球科学联合学术年会

作者： Gaohua Zhu douglas a.wiens Hongfeng Yang Jian Lin Min Xu3 Qingyu You The Chinese University of Hong Kong Hong Washington University in St Louis South China Sea Institute of Oceanology Woods Hole Oceanographic Institution Institute of Geology and Geophysics

Extensional faults within the incoming plates at subduction zones provide an important pathway to transport water into the Earth, leading to a pervasively serpentinized region. The extent and degree of mantle hydratio... 详细信息

关键词： Upper mantle hydration indicated by decreased shear velocity near the Southern Mariana Trench from Rayleigh wave tomography Rayleigh Southern

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南极中山站-昆仑站间地壳厚度分布

极地研究 2014年第2期26卷 177-185页

作者：冯梅安美建安春雷史贵涛赵越李院生 douglas wiens 中国地质科学院地质力学研究所北京100081 中国极地研究中心上海200136 Department of Earth and Planetary Science Washington University

自第4个国际极地年2007/2008开始至2013年,中国南极内陆冰盖科考队相继在自南极大陆边缘的中山站至东南极地形最高点昆仑站(Dome A)一线进行了低温甚宽频地震观测。本文对7个天然地震台站数据进行了分析,提取了这些台站的S波接收函数,... 详细信息

自第4个国际极地年2007/2008开始至2013年,中国南极内陆冰盖科考队相继在自南极大陆边缘的中山站至东南极地形最高点昆仑站(Dome A)一线进行了低温甚宽频地震观测。本文对7个天然地震台站数据进行了分析,提取了这些台站的S波接收函数,据此反演获得了这些台站下的地壳厚度分布。结果显示:随着纬度的升高,地壳厚度由大陆边缘的中山站下的约38 km逐渐增加至CHNB台下的58 km,随后又于CHNA台站下方减薄至47 km,然后快速增大到南极地形最高点昆仑站(Dome A)下的62 km。昆仑站或Dome A是南极大陆地壳最厚的地方。从中山站至昆仑站之间地壳厚度的变化与冰下地貌变化存在明显的相关性,它们都说明了从中山站至CHNB之间地壳构造相对均匀。在距昆仑站约200 km的CHNA台下的地壳厚度(约47 km)明显比临近台站地壳偏薄,这可能说明了甘伯采夫山脉地壳侧向变化较大,即其形成时所遭受的构造作用较复杂。

关键词：地壳厚度接收函数昆仑站东南极南极内陆科考

Forests,atmospheric water and an uncertain future: the new biology of the global water cycle

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Forest Ecosystems 2018年第3期5卷 236-257页

作者： douglas Sheil Faculty of Environmental Sciences and Natural Resource Management(MINA) Norwegian University of Life Sciences (NMBU)

Theory and evidence indicate that trees and other vegetation influence the atmospheric water-cycle in various *** influences are more important, more complex, and more poorly characterised than is widely *** there is little doubt that changes in tree cover will impact the water-cycle, the wider consequences remain difficult to predict as the underlying relationships and processes remain poorly characterised. Nonetheless, as forests are vulnerable to human activities, these linked aspects of the water-cycle are also at risk and the potential consequences of large scale forest loss are severe. Here, for non-specialist readers, I review our knowledge of the links between vegetation-cover and climate with a focus on forests and rain(precipitation). I highlight advances, uncertainties and research opportunities. There are significant shortcomings in our understanding of the atmospheric hydrological cycle and of its representation in climate models. A better understanding of the role of vegetation and tree-cover wil reduce some of these shortcomings. I outline and il ustrate various research themes where these advances may be *** themes include the biology of evaporation, aerosols and atmospheric motion, as well as the processes that determine monsoons and diurnal precipitation cycles. A novel theory—the ‘biotic pump’—suggests that evaporation and condensation can exert a major influence over atmospheric dynamics. This theory explains how high rainfall can be maintained within those continental land-masses that are sufficiently forested. Feedbacks within many of these processes can result in non-linear behaviours and the potential for dramatic changes as a result of forest loss(or gain): for example, switching from a wet to a dry local climate(or visa-versa). Much remains unknown and multiple research disciplines are needed to address this: forest scientists and other biologists have a major role to *** ideas, methods and data offer opportun

关键词： Biotic pump Climate Condensation Evaporation Ice-nucleation Transpiration GCM Vapour Water-cycle

Materials and technology of Chinese jades dating to the Western Zhou period (1050―771 BCE)

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Science China(Technological Sciences) 2008年第4期51卷 467-480页

作者： Janet G douglas Department of Conservation and Scientific Research Freer Gallery of Art / Arthur M. Sackler Gallery Smithsonian Institution

Excavated jades dating to the Western Zhou period (1050―771 BCE) from the Xi’an area in Shaanxi Province, China, and contemporaneous jades in the collections of the Arthur M. Sackler Gallery at the Smithsonian Institution have been studied to learn about the jade and stone materials and how they were worked during the Western Zhou period. Materials identification was carried out using a combination of techniques such as Fourier-transform infrared spectroscopy and X-ray diffraction. Tool marks were studied using stereomicroscopy and examination of mold impressions using scanning electron microscopy. All of these objects were pro- duced through simple processes involving solid drilling, riffling, and sharp point abrasion; and no evidence was found for the use of rotary tools for incising or sawing.

关键词： jade nephrite stone China Western Zhou scanning electron microscopy materials technology tool marks

Interpreting forest diversity-productivity relationships:volume values,disturbance histories and alternative inferences

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Forest Ecosystems 2020年第1期7卷 64-75页

作者： douglas Sheil Frans Bongers Faculty of Environmental Sciences and Natural Resource Management(MINA) Norwegian University of Life Sciences(NMBU)Box 50031432 AsNorway Forest Ecology and Forest Management Group Wageningen University&ResearchPO Box 476700 AA WageningenThe Netherlands

Understanding the relationship between stand-level tree diversity and productivity has the potential to inform the science and management of *** shows that plant diversity-productivity relationships are challenging to interpret—and this remains true for the study of forests using non-experimental field *** we highlight pitfalls regarding the analyses and interpretation of such *** examine three themes:1)the nature and measurement of ecological productivity and related values;2)the role of stand history and disturbance in explaining forest characteristics;and 3)the interpretation of any *** show that volume production and true productivity are distinct,and neither is a demonstrated proxy for economic *** stand characteristics,including diversity,volume growth and productivity,vary intrinsically with succession and stand *** should be characterising these relationships rather than ignoring or eliminating *** to do so may lead to misleading *** illustrate,we examine the study which prompted our concerns—Liang et al.(Science 354:aaf8957,2016)—which developed a sophisticated global analysis to infer a worldwide positive effect of biodiversity(tree species richness)on“forest productivity”(stand level wood volume production).Existing data should be able to address many of our *** evaluations will improve understanding.

关键词： Causation Correlation Diversity Inference Productivity Richness Tree-growth Wood-density

The Effect of Natural Hazard Damage on Manufacturing Value Added and the Impact of Spatiotemporal Data Variations on the Results

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International Journal of Disaster Risk Science 2022年第5期13卷 691-704页

作者： douglas Thomas Jennifer Helgeson National Institute of Standards and Technology GaithersburgMD 20899USA

This study examined the effect of natural hazards on manufacturing industry value added and the sensitivity of the results from changes to spatiotemporal resolution of the *** measured the negative effects of hazards,rather than the net *** models were developed with varying spatio temporal units for the continental United States:annual/county units;annual/state units;and quarterly/state *** simulations were run using each model to estimate the negative effect of damage from all natural hazards on value added across spatiotemporal ***,an investment analysis was conducted to examine the return from public investments in hazard *** results do not demonstrate that,locally,natural hazards reduce value ***,the evidence suggests that natural hazards in the upstream supply chain have statistically significant impact when modeled at the annual/county scale and at the quarterly/state *** local nor supply chain hazards have a statistically significant effect when modeled at the annual/state scale,suggesting that broader spatiotemporal units may obscure the true downstream effects of natural *** investment analysis,utilizing model results,suggests that an investment of USD 100 billion or less is economical if it results in a reduction in losses of 10% or more.

关键词： Manufacturing Natural hazards Spatiotemporal impacts United States Value added

Slab and Level 2 Automation Design Guidelines for Optimum Metallurgy and Productivity for Plate and Steckel Mills

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Journal of Iron and Steel Research International 2011年第S1期18卷 550-556页

作者： Stalheim douglas DGS Metallurgical Solutions Inc. 15003 NE 10th StreetVancouverWA 98684 USA

Many new steel plate processing facilities have been built in the past 10 years around the world with many more being planned for the *** is especially true in developing countries such as China,India and *** of these facilities are plate mills with either one or two stands or a Steckel mill,typically only one stand designed for the production of structural plate ***,there is a lack of understanding with both the mill builders of the world and the mill owners on the importance of properly matching up the available slab supply (either new as part of a new plate/Steckel mill complex or part of an already existing) with the desired end plate product *** mill builders and owners around the world believe that you can take any slab of any dimension and make any plate dimension you *** this is basically true with today’s Level 2 automation systems,it does not always result in optimum metallurgy/mechanical properties or *** less than optimum condition results in mechanical property failures,shape issues,productivity losses and in general a less than desirable costly processing *** is important to the overall optimization of a steel processing facility that the proper slab dimensions be used to produce the proper final plate dimensions along with achieving the required mechanical *** critical nature of this selection will be dependent on the final plate thickness and overall mechanical property *** mechanical property,shape and overall microstructure are heavily dependent on the ability to properly work the entire cross section of the slab through the rolling *** mechanical property,shape and microstructural issues are a result of improper working of the entire cross section during *** ability for a given mill to properly work the entire cross section is dependent on proper slab selection (total reduction ratio) and a proper rolling schedule either generated manual

关键词： slab dimensions optimization grain size rolling schedule automation Level 2

Metallurgical Optimization of Microalloyed Steels for Oil and Gas Transmission Pipelines

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Journal of Iron and Steel Research International 2011年第S1期18卷 669-674页

作者： Stalheim douglas DGS Metallurgical Solutions Inc. 15003 NE 10th StreetVancouverWA98684 USA

The production of microalloyed steels for oil and gas transmission pipelines has increased significantly over the past *** more and more countries developing their own capabilities to produce pipeline steels to support their own internal pipeline infrastructure development,there has been an increase of steel producers working to develop their own capabilities to produce microalloyed steels for this ***,to achieve the desired mechanical property attributes for transmission pipeline applications utilizing a cost effective approach requires metallurgical optimization of the microalloyed *** achieve metallurgical optimization a basic understanding is required in the design of a cost effective alloy and then the proper processing of that alloy design to achieve the optimum microstructure/mechanical *** this sense,many producers in the world,especially those who have only recently,in the past 10 years,developed their capability to produce microalloyed transmission pipeline steels still do not achieve metallurgical optimization of their alloy and *** results in yield losses due to failures,inefficient processing causing productivity losses and additional expensive additions of alloys to compensate for failures and process *** the supplier of plate/coil has the largest percentage effect on the final cost of the pipe,the steel producer must understand proper alloy,microstructure,and process design to produce a uniform and stable plate/coil to be used in pipe *** means that strength,toughness and microstructure must be uniform down the length,across the width and through the cross *** optimization is achieved when this uniformity is achieved with a cost effective *** to that,non-uniformity results in pipe forming,welding,expansion,mechanical property and production issues resulting in downgraded pipe and cost overruns in *** paper will describe targets for p

关键词： microalloy niobium pipeline solubility grain size rolling schedule

50 years change in urban land use and ecological planning globally in the era of design with nature

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Ecosystem Health and Sustainability 2019年第1期5卷 185-198,I0001页

作者： Ian douglas School of Environment Education and DevelopmentUniversity of ManchesterManchesterUK

Ian McHarg’s 1969 book,Design with Nature,was grounded in earlier good practice,especially the European vision of fitting cities into the regional landscape and carrying thorough surveys before planning *** book emerged in the wake of publications that worried about the ability of the earth to support expanding populations and their growing impact on the *** argued that ecological design should follow planning based on detailed site *** McHarg advised many urban authorities in the USA and other countries,especially in Africa,Asia and Europe,and his ideas had influenced some British new towns,they had little attention in the planning of Milton Keynes,England’s largest new urban settlement,where the initial geological surveys were inadequate,but a successful large tree-planting programhas created a“city in the forest.”McHarg was however closely involved in planning the Nigerian Capital city,Abuja,but his sound master plan was ill-equipped to provide for a nation undergoing post-conflict rebuilding and a local population more concerned with access to land than ecological ***,McHarg helped us to promote,protect,and preserve urban green *** teams from different disciplines now work well together,the integrated thinking advocated by McHarg remains sometimes in short supply in local practice.

关键词： Planning design urban nature garden city site investigation