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History and evaluation of national-scale geochemical data sets for the United States

Geoscience Frontiers 2013年第2期4卷 167-183页

作者： David b.Smith Steven M.Smith john D.Horton U.S.Geological Survey.Denver Federal Center MS 973.DenverCO 80225USA

Six national-scale,or near national-scale,geochemical data sets for soils or stream sediments exist for the United *** earliest of these,here termed the ＇Shacklette＇ data set,was generated by a U.S. Geological Survey（USGS） project conducted from 1961 to *** project used soil collected from a depth of about 20 cm as the sampling medium at 1323 sites throughout the conterminous *** National Uranium Resource Evaluation Hydrogeochemical and Stream Sediment Reconnaissance（NUREHSSR） Program of the *** 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 *** *** sampled area represented about 65%of 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 *** data set contains analyses of more than 3000 *** 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 *** covered by the NURE-HSSR *** data set contains chemical analyses for more than 70,000 *** 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 *** of three horizons or depths at more than 4800 sites in the *** completed in 2010,and chemical analyses are currently *** NRCS initiated a project in the 1990s to analyze the various soil horizons from selected pedons throughout the *** data set currently contains data from more than 1400 *** 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

关键词： Geochemical mapping National-scale geochemical data Geochemical baselines United States

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Application of Generalized Standard Addition Method and Ultraviolet Spectroscopy to Quantify Electrolytic Depolymerization of Lignin

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Journal of Analysis and Testing 2020年第1期4卷 35-44页

作者： Zewei Chen Mahtab NaderiNasrabadi john A.Staser Peter b.Harrington Department of Chemistry and biochemistry Clippinger LaboratoriesOhio UniversityAthensOH 45701USA Department of Chemical and biomolecular Engineering Center for Electrochemical Engineering ResearchOhio UniversityAthensOH 45701USA

Industrial lignin waste is an important byproduct of bio-refineries and the paper *** of industrial lignin could generate useful aromatic *** group has focused on electrolytic decomposition of biorefinery *** quantify electrolytic decomposition of the lignin in a highly caustic solution,ultraviolet(UV)spectroscopy provides a useful *** conversion of the neat lignin to the oxidized products achieved by the electrolytic reactor may be measured by quantifying the amount of unreacted neat lignin that remains in the *** the properties of electrolytic decomposition products are largely unknown,a useful approach to quantify decomposition of the neat lignin is to use a multivariate calibration method referred to as the generalized standard addition method(GSAM).In this approach,the electrolytic decomposition products represent a background interference and the neat lignin that remains can be *** approach allows the conversion of the neat lignin to be calculated in a solution that is a complex mixture.

关键词： GSAM Lignin depolymerization Electrolytic reactor UV spectroscopy best linear unbiased estimator(bLUE)

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STOCHASTIC SYSTEM IDENTIFICATION VIA ADAPTIVE SPECTRAL FACTORIZATION

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Systems Science and Mathematical Sciences 1991年第3期4卷 275-288页

作者：郭雷 john b.Moore Institute of Systems Science Academia SinicaBeijing 100080China Department of Systems Engineering Research School of Physical SciencesAustralian National UniversityG.P.O.Box 4CanberraA.C.T.2601Australia

We consider in this paper the problem of recursive identification for stochastic systemswhen the noise model does not satisfy the positive real condition associated with convergence ofstandard *** avoid the positive real condition,adaptive spectral factorization techniquesare exploited on the basis of a class of non-standard time-varying recursive Riccati *** properties of the Riccati equations are studied as a crucial step to the convergence resultsof the paper.

关键词： Adaptive parameter estimation spectral factorization

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Robotic pancreatic surgery: a slowly developing field

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Hepatobiliary Surgery and Nutrition 2020年第5期9卷 673-675页

作者： Patrick N.Salibi john b.Martinie Division of Hepatobiliary and Pancreatic Surgery Department of SurgeryAtrium Health Carolinas Medical CenterCharlotteNCUSA

Robotic surgery has undergone rapid development over the last several decades and minimally invasive surgery has become the standard of care for many surgical *** adoption within the world of hepatobiliary and pancreas surgery has been tempered by the complexity of the *** reports showcased the feasibility of distal pancreatectomy and pancreaticoduodenectomy in a minimally invasive fashion and where followed by case series demonstrating its safety and efficacy(1,2).This has since been confirmed with large matched cohorts confirming at a minimum oncologic equivalence between minimally invasive pancreatic resections as compared to open procedures(3).Given the complexity of pancreatic surgery and the inherent limitations of laparoscopic surgery the robotic surgical platform has seen an exponential rise in attention with its role in minimally invasive pancreatic *** this interest there have been two consensus guidelines published on minimally invasive pancreatic surgery demonstrating its growth within the field(4,5).

关键词： surgery slowly matched

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新型带宽调制型Mott化合物的高压合成及其金属化相变

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物理 2007年第8期36卷 584-587页

作者：龙有文杨留响靳常青周建十 J b.goodenough 中国科学院物理研究所北京凝聚态物理国家实验室北京100080 Texas Materials Institute University of Texasat AustinUSA

利用高温高压条件,制备了(SrCa)CrO3系列带宽可调型的钙钛矿Mott化合物。在10GPa的外加压力下,观察到SrCrO3的绝缘体-金属化相变。原位高压X射线衍射实验表明,Sr/CaCrO3晶体结构在0-9GPa压力范围内保持稳定。但SrCrO3在4GPa时存在着电... 详细信息

利用高温高压条件,制备了(SrCa)CrO3系列带宽可调型的钙钛矿Mott化合物。在10GPa的外加压力下,观察到SrCrO3的绝缘体-金属化相变。原位高压X射线衍射实验表明,Sr/CaCrO3晶体结构在0-9GPa压力范围内保持稳定。但SrCrO3在4GPa时存在着电子结构变化所引起的等结构相变,表现为体弹性模量的反常软化。此外,由于电子关联效应,磁性和热输运性质的测试结果表明了材料的奇异电子态特征。

关键词：带宽调控型Mott化合物高压合成高压金属化相变

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Evaluation of method performance for osteometric sorting of commingled human remains

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Forensic Sciences Research 2018年第4期3卷 343-349页

作者： john E.byrd Carrie b.LeGarde Laboratory Defense POW/MIA Accounting AgencyJoint Base Pearl Harbor-HickamHIUSA

Evaluation of method performance involves the consideration of numerous factors that can contribute to error.A variety of measures of performance can be borrowed from the signal detection literature and others are drawn from statistical *** article demonstrates the principles of performance evaluation by applying multiple measures to osteometric sorting models for paired elements run against data from known *** indicate that false positive rates are close,on average,to expected *** assemblage size grows,the false positive rate becomes unimportant and the false negative rate becomes *** disparity among the commingled individuals plays a significant role in method performance,showing that case-specific circumstances(*** size and size disparity)will determine method power.

关键词： Forensic sciences forensic anthropology statistics test method method performance error signal detection osteometric sorting

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Preface

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Chinese Science bulletin 2012年第32期57卷 4103-4103页

作者： goodenough john b the US National Academy of Engineering the University of Texas at Austin Texas Materials Institute

Energy is stored and transported most easily as chemical energy. The fossil fuels represent solar energy captured and stored as chemical energy by plants over many millions of years. Modern economies depend on this finite, non-renewable energy store. The inexorable march to a global economy and the rising expectations of an expanding world population place ever greater demands on the finite resources of

关键词：天然气资源化石燃料国家竞争力现代经济世界人口全球经济化学能超过数

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What diameter?What height?Influence of measures of average tree size on area-based allometric volume relationships

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Forest Ecosystems 2024年第1期11卷 100-109页

作者： Yilin Wang john A.Kershaw Mark J.Ducey Yuan Sun James b.McCarter Integrated Forest Mensuration and Systems Analysis Laboratory Faculty of Forestry and Environmental ManagementUniversity of New BrunswickFrederictonNBCanada Department of Natural Resources and the Environment University of New HampshireDurhamNHUSA College of Forestry Nanjing Forestry UniversityNanjing210037China Scientific Programmer RayonierYuleeFLUSA

Volume is an important attribute used in many forest management *** from 83 fixed-area plots located in central New brunswick,Canada,are used to examine how different measures of stand-level diameter and height influence volume prediction using a stand-level variant of Honer's(1967)volume *** density was included in the models(Volume=f(Diameter,Height,Density))choice of diameter measure was more important than choice of height *** density was not included(Volume=f(Diameter,Height)),the opposite was *** models with density included,moment-based estimators of stand diameter and height performed better than all other *** models without density,largest tree estimators of stand diameter and height performed better than other *** overall best equation used quadratic mean diameter,Lorey's height,and density(root mean square error=5.26 m^3·ha^(-1);1.9%relative error).The best equation without density used mean diameter of the largest trees needed to calculate a stand density index of 400 and the mean height of the tallest 400 trees per ha(root mean square error=32.08 m^(3)·ha^(-1);11.8%relative error).The results of this study have some important implications for height subsampling and LiDAR-derived forest inventory analyses.

关键词： Allometric relationships Stand structure Volume estimation Stand-level attributes

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An imputation/copula-based stochastic individual tree growth model for mixed species Acadian forests： a case study using the Nova Scotia permanent sample plot network

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Forest Ecosystems 2017年第4期4卷 251-263页

作者： john A. Kershaw Jr Aaron R. Weiskittel Michael b. Lavigne Elizabeth McGarrigle University of New brunswick FrederictonNBCanada University of Maine OroooMEUSA Atlantic Forestry Centre Natural Resources Canada.FrederiaooNBCanada Nova Scotia Natural Resources Forestry DivisionTruroNS B2N 0G9UK.

background： A novel approach to modelling individual tree growth dynamics is proposed. The approach combines multiple imputation and copula sampling to produce a stochastic individual tree growth and yield projection system. Methods： The Nova Scotia, Canada permanent sample plot network is used as a case study to develop and test the modelling approach. Predictions from this model are compared to predictions from the Acadian variant of the Forest Vegetation Simulator, a widely used statistical individual tree growth and yield model. Results： Diameter and height growth rates were predicted with error rates consistent with those produced using statistical models. Mortality and ingrowth error rates were higher than those observed for diameter and height, but also were within the bounds produced by traditional approaches for predicting these rates. Ingrowth species composition was very poorly predicted. The model was capable of reproducing a wide range of stand dynamic trajectories and in some cases reproduced trajectories that the statistical model was incapable of reproducing. Conclusions： The model has potential to be used as a benchmarking tool for evaluating statistical and process models and may provide a mechanism to separate signal from noise and improve our ability to analyze and learn from large regional datasets that often have underlying flaws in sample design.

关键词： Nearest neighbor imputation Copula sampling Individual tree growth model Mortality Ingrowth Mixed species stand development Acadian forests Nova Scotia

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Predicting glass structure by physics-informed machine learning

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npj Computational Materials 2022年第1期8卷 1839-1847页

作者： Mikkel L.bødker Mathieu bauchy Tao Du john C.Mauro Morten M.Smedskjaer Department of Chemistry and bioscience Aalborg University9220AalborgDenmark Physics of AmoRphous and Inorganic Solids Laboratory(PARISlab) Department of Civil and Environmental EngineeringUniversity of CaliforniaLos AngelesCA90095USA Department of Materials Science and Engineering The Pennsylvania State UniversityUniversity ParkPA16802USA

Machine learning(ML)is emerging as a powerful tool to predict the properties of materials,including *** ML models with knowledge of how glass composition affects short-range atomic structure has the potential to enhance the ability of composition-property models to extrapolate accurately outside of their training ***,we introduce an approach wherein statistical mechanics informs a ML model that can predict the non-linear composition-structure relations in oxide *** combined model offers an improved prediction compared to models relying solely on statistical physics or machine learning ***,we show that the combined model accurately both interpolates and extrapolates the structure of Na_(2)O–SiO_(2)***,the model is able to extrapolate predictions outside its training set,which is evidenced by the fact that it is able to predict the structure of a glass series that was kept fully hidden from the model during its training.

关键词： glasses structure glass

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