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History and Progress of the North American Soil Geochemical Landscapes Project,2001-2010 被引量:7
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作者 david b.smith William F.Cannon +3 位作者 Laurel G.Woodruff Francisco Moreira Rivera Andrew N.Rencz Robert G.Garrett 《地学前缘》 EI CAS CSCD 北大核心 2012年第3期19-32,共14页
In 2007,the U.S.Geological Survey,the Geological Survey of Canada,and the Mexican Geological Survey initiated a low-density(1 site per 1600 km2,13323 sites) geochemical and mineralogical survey of North American soils... In 2007,the U.S.Geological Survey,the Geological Survey of Canada,and the Mexican Geological Survey initiated a low-density(1 site per 1600 km2,13323 sites) geochemical and mineralogical survey of North American soils(North American Soil Geochemical Landscapes Project).Sampling and analytical protocols were developed at a series of workshops in 2003-2004 and pilot studies were conducted from 2004-2007.The ideal sampling protocol at each site includes a sample from 0-5 cm depth,a composite of the soil A horizon,and a sample from the soil C horizon.The <2-mm fraction of each sample is analyzed for Al,Ca,Fe,K,Mg,Na,S,Ti,Ag,Ba,Be,Bi,Cd,Ce,Co,Cr,Cs,Cu,Ga,In,La,Li,Mn,Mo,Nb,Ni,P,Pb,Rb,Sb,Sc,Sn,Sr,Te,Th,Tl,U,V,W,Y,and Zn by inductively coupled plasma-mass spectrometry and inductively coupled plasma-atomic emission spectrometry following a near-total digestion in a mixture of HCl,HNO3,HClO4,and HF.Separate methods are used for As,Hg,Se,and total C on this same size fraction.The major mineralogical components are determined by a quantitative X-ray diffraction method.Sampling in the conterminous U.S.was completed in 2010(c.4800 sites) with chemical and mineralogical analysis currently underway.In Mexico,approximately 66% of the sampling(871 sites) had been done by the end of 2010 with completion expected in 2012.After completing sampling in the Maritime provinces and portions of other provinces(472 sites,7.6% of the total),Canada withdrew from the project in 2010.Preliminary results for a swath from the central U.S.to Florida clearly show the effects of soil parent material and climate on the chemical and mineralogical composition of soils.A sample archive will be established and made available for future investigations. 展开更多
关键词 墨西哥 地质学 电感耦合 等离子体
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The IUGS/IAGC Task Group on Global Geochemical Baselines 被引量:5
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作者 david b.smith Shaun Reeder Alecos Demetriades 《地学前缘》 EI CAS CSCD 北大核心 2012年第3期1-6,共6页
The Task Group on Global Geochemical Baselines,operating under the auspices of both the International Union of Geological Sciences(IUGS) and the International Association of Geochemistry(IAGC),has the long-term goal o... The Task Group on Global Geochemical Baselines,operating under the auspices of both the International Union of Geological Sciences(IUGS) and the International Association of Geochemistry(IAGC),has the long-term goal of establishing a global geochemical database to document the concentration and distribution of chemical elements in the Earth's surface or near-surface environment.The database and accompanying element distribution maps represent a geochemical baseline against which future human-induced or natural changes to the chemistry of the land surface may be recognized and quantified.In order to accomplish this long-term goal,the activities of the Task Group include:(1) developing partnerships with countries conducting broad-scale geochemical mapping studies;(2) providing consultation and training in the form of workshops and short courses;(3) organizing periodic international symposia to foster communication among the geochemical mapping community;(4) developing criteria for certifying those projects whose data are acceptable in a global geochemical database;(5) acting as a repository for data collected by those projects meeting the criteria for standardization;(6) preparing complete metadata for the certified projects;and(7) preparing,ultimately,a global geochemical database.This paper summarizes the history and accomplishments of the Task Group since its first predecessor project was established in 1988. 展开更多
关键词 国际地质科学联合会 伴生元素 化学元素 地表环境
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History and evaluation of national-scale geochemical data sets for the United States 被引量:8
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作者 david b.smith Steven M.Smith John D.Horton 《Geoscience Frontiers》 SCIE CAS CSCD 2013年第2期167-183,共17页
Six national-scale,or near national-scale,geochemical data sets for soils or stream sediments exist for the United States.The earliest of these,here termed the 'Shacklette' data set,was generated by a U.S. Geologica... Six national-scale,or near national-scale,geochemical data sets for soils or stream sediments exist for the United States.The earliest of these,here termed the 'Shacklette' data set,was generated by a U.S. Geological Survey(USGS) project conducted from 1961 to 1975.This project used soil collected from a depth of about 20 cm as the sampling medium at 1323 sites throughout the conterminous U.S.The National Uranium Resource Evaluation Hydrogeochemical and Stream Sediment Reconnaissance(NUREHSSR) Program of the U.S.Department of Energy was conducted from 1975 to 1984 and collected either stream sediments,lake sediments,or soils at more than 378,000 sites in both the conterminous U.S.and Alaska.The sampled area represented about 65%of the nation.The Natural Resources Conservation Service(NRCS),from 1978 to 1982,collected samples from multiple soil horizons at sites within the major crop-growing regions of the conterminous U.S.This data set contains analyses of more than 3000 samples.The National Geochemical Survey,a USGS project conducted from 1997 to 2009,used a subset of the NURE-HSSR archival samples as its starting point and then collected primarily stream sediments, with occasional soils,in the parts of the U.S.not covered by the NURE-HSSR Program.This data set contains chemical analyses for more than 70,000 samples.The USGS,in collaboration with the Mexican Geological Survey and the Geological Survey of Canada,initiated soil sampling for the North American Soil Geochemical Landscapes Project in 2007.Sampling of three horizons or depths at more than 4800 sites in the U.S.was completed in 2010,and chemical analyses are currently ongoing.The NRCS initiated a project in the 1990s to analyze the various soil horizons from selected pedons throughout the U.S.This data set currently contains data from more than 1400 sites.This paper(1) discusses each data set in terms of its purpose,sample collection protocols,and analytical methods;and(2) evaluates each data set in terms of its appropriateness as a national-scale geochemical database and its usefulness for nationalscale geochemical mapping. 展开更多
关键词 Geochemical mapping National-scale geochemical data Geochemical baselines United States
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模拟训练中的自动化武力对抗
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作者 Philip S.Anton Kenneth L.McAdow +3 位作者 david b.smith Paul F.Lehner Cdr.Michael A.Sharp 刘庆文 《舰船指挥控制系统》 1996年第3期45-53,共9页
对于军事模拟训练的成功应用,逼真的武力对抗是很关键的。不幸的是,一些因素使得仿真武力对抗的人工控制难以实现甚至不可能实现。本文探讨了这些因素并讨论了在强交互性情形下,自动交互式目标(AIT)如何帮助训练演习控制者(TEC)提供有... 对于军事模拟训练的成功应用,逼真的武力对抗是很关键的。不幸的是,一些因素使得仿真武力对抗的人工控制难以实现甚至不可能实现。本文探讨了这些因素并讨论了在强交互性情形下,自动交互式目标(AIT)如何帮助训练演习控制者(TEC)提供有效、真实的武力对抗。原型远程AIT处理系统(RAPS)的特性说明了如何根据TEC对自动化实体的要求来设计一个AIT系统。RAPS可为现有系统或新系统提供对AIT的遥控,其优良的特性能使TEC自由地选择和控制AIT进行个别训练演习和全体船员的熟练演习。 展开更多
关键词 模拟训练 军事训练 武力对抗
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美国Richard Chai临时商店
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作者 Daniel Arsham Alex Mustonen +3 位作者 david b.smith Lexie Moreland Snarkltecture 代照 《现代装饰》 2012年第4期64-69,共6页
纽约当红韩裔时尚造型设计师理查蔡(RichardChei),联手Snarkitecture设计公司的DanielArsham和AlBxMustenen在纽约制作了一家艋时售卖店。它是BOFFO举办的建筑与时尚展系列的一部分。此项目的霉售装置用单一材料进行造型,整体空间... 纽约当红韩裔时尚造型设计师理查蔡(RichardChei),联手Snarkitecture设计公司的DanielArsham和AlBxMustenen在纽约制作了一家艋时售卖店。它是BOFFO举办的建筑与时尚展系列的一部分。此项目的霉售装置用单一材料进行造型,整体空间非常特别,顾客像置身于“北极冰川洞窟“中购物。 展开更多
关键词 商店 美国 整体空间 设计师 造型 时尚 纽约 建筑
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