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Critical review of the impact of cover crops on soil properties

International Soil and Water Conservation Research 2022年第3期10卷 343-354页

作者： Komlan Koudahe Samuel Callen Koffi Djaman Biological and Agricultural Engineering Department Kansas State University1016 Seaton Hall920 N.Martin Luther King Jr.DriveManhattanKS66506USA Department of Plant and Environmental Sciences New Mexico State UniversityAgricultural Science Center at FarmingtonP.O.Box 1018FarmingtonNM87499USA

Grasses as well as leguminous and non-leguminous broadleaves are the major categories of commonly grown cover crops *** review focuses on the contribution of cover crops to soil *** review first considers the single and mixed cover crops and shows that grass species are desirable for their decay and ability to provide substantial soil cover,broadleaf species are used for their quick decomposition and capacity of releasing residues into the soil,while the leguminous species are used for their ability to fix atmospheric ***,the impacts of cover crops on soil health are *** cover crops into conventional cropping systems may reduce soil bulk density,improve soil structure and hydraulic properties to facilitate increased water infiltration and *** residue additions from cover crops may enhance soil organic C and N accretion as well as increase availability of P,K,Ca,Fe and Mg in some soil types under certain climatic ***,cover crops may provide a better condition for microbial activity,abundance,and ***,the review shows that through proper management,cover crops may be utilized as an essential component of soil conservation practices for enhanced soil ***,further investigation is necessary to determine cover crop effects in additional cropping systems and climatic zones as well as the long-term effects of cover crops on soil properties,subsequent crop yield,and overall cropping system *** review is an important source of information for crop growers,crop management institutions,universities,and crop consultants for sustainable agricultural production.

关键词： Cover crops Soil properties Grasses Leguminous

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Porous Medium Flow with Both a Fractional Potential Pressure and Fractional Time Derivative

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Chinese Annals of Mathematics,Series B 2017年第1期38卷 45-82页

作者： Mark allen Luis CAFFARELLI Alexis VASSEUR Department of Mathematics The University of Texas at AustinAustinTX 78712USA

The authors study a porous medium equation with a right-hand side. The operator has nonlocal diffusion effects given by an inverse fractional Laplacian *** derivative in time is also fractional and is of Caputo-type, which takes into account"memory". The precise model isD_t~αu- div(u(-Δ)^(-σ)u) = f, 0 < σ <1/*** paper poses the problem over {t ∈ R^+, x ∈ R^n} with nonnegative initial data u(0, x) ≥0 as well as the right-hand side f ≥ 0. The existence for weak solutions when f, u(0, x)have exponential decay at infinity is proved. The main result is H¨older continuity for such weak solutions.

关键词： Caputo derivative Marchaud derivative Porous medium equation Hlder continuity Nonlocal diffusion

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Many-Body Correlation Effects on the xBjorken-Dependence of Cross Section Ratios off Nuclei for 1 <xBjorken<2

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Journal of Modern Physics 2022年第1期13卷 56-65页

作者： Athanasios Petridis allen Barr Drew Fustin Department of Physics and Astronomy Drake University Des Moines USA

Many-body correlations in nuclei determine the behavior of Deep-Inelastic-Scattering (DIS) and Quasi-Elastic Scattering (QES) cross section ratios off heavy over light nuclei especially for xBjorken > 1, obtained at Jefferson Lab. They can be described in terms of quark-cluster formation in nuclei due to wave-function overlapping, manifesting itself when the momentum transfer is high so that the partonic degrees of freedom are resolved. In clusters (correlated nucleons) the quark and gluon momentum distributions are softer than in single nucleons and extend to xBjorken > 1. The cluster formation probabilities are computed using a network-defining algorithm in which the initial nucleon density is either standard Woods-Saxon or is input from lower energy data while the critical radius for nucleon merging is an adjustable parameter. The exact choice of critical radius depends on the specific nucleus and it is anti-correlated to the rescaling of the xBjorken needed for bound nucleons. The calculations show that there is a strong dependence of the cross section ratios on the xBjorken in agreement with the data and that four-body correlations are needed to explain the experimental results even in the range 1 xBjorken < 2. The dependence on the specific exponents of parton distributions in high-order clusters is weak.

关键词： Deep Inelastic Scattering Quasi-Elastic Scattering Short-Range Correlations Quark-Clusters

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Nanoscale perspective： Materials designs and understandings in lithium metal anodes

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Nano Research 2017年第12期10卷 4003-4026页

作者： Dingchang Lin Yayuan Liu allen Pei Yi Cui Department of Materials Science and Engineering Stanford University Stanford California 94305 USA Stanford Institute for Materials and Energy Sciences SLAC National Accelerator Laboratory 2575 Sand Hill Road Menlo Park California 94025 USA

Li metal chemistry is a promising alternative with a much higher energy density than that of state-of-the-art Li-ion counterparts. However, significant challenges including safety issues and poor cyclability have severely impeded Li metal technology from becoming viable. In recent years, nanotechnologies have become increasingly important in materials design and fabrication for Li metal anodes, contributing to major progress in the field. In this review, we first introduce the main achievements in Li metal battery systems fulfilled by nanotechnologies, particularly regarding Li metal anode design and protection, ultrastrong separator engineering, safety monitoring, and smart functions. Next, we introduce recent studies on nanoscale Li nucleation/deposition. Finally, we discuss possible future research directions. We hope this review delivers an overall picture of the role of nanoscale approaches in the recent progress of Li metal battery technology and inspires more research in the future.

关键词： lithium metal anodes nanoscale lithiumnucleation

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Soil microbial response to waste potassium silicate drilling fluid

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Journal of Environmental Sciences 2015年第3期27卷 189-198页

作者： Linjun Yao M.Anne Naeth allen Jobson Department of Renewable Resources University of Alberta School of Land Science and Technology China University of Geosciences (Beijing)

Potassium silicate drilling fluids （PSDF） are a waste product of the oil and gas industry with potential for use in land reclamation. Few studies have examined the influence of PSDF on abundance and composition of soil bacteria and fungi. Soils from three representative locations for PSDF application in Alberta, Canada, with clay loam, loam and sand textures were studied with applications of unused, used once and used twice PSDF. For all three soils, applying ≥40 m^3/ha of used PSDF significantly affected the existing soil microbial flora. No microbiota was detected in unused PSDF without soil. Adding used PSDF to soil significantly increased total fungal and aerobic bacterial colony forming units in dilution plate counts, and anaerobic denitrifying bacteria numbers in serial growth experiments. Used PSDF altered bacterial and fungal colony forming unit ratios of all three soils.

关键词： Drilling waste Potassium silicate drilling fluid Soil Microbiota

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Additive manufacturing of precision optics at micro and nanoscale

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International Journal of Extreme Manufacturing 2019年第1期1卷 92-109页

作者： Abolfazl Zolfaghari Tiantong Chen allen Y Yi The Ohio State University 210 Baker Systems 1971 Neil Ave ColumbusOH 43017United States of America

This review focuses on recent developments in additive manufacturing(AM)of precision optical devices,particularly devices consisting of components with critical features at the micro-and *** include,but are not limited to,microlenses,diffractive optical elements,and photonic ***,optical devices with large-size lenses and mirrors are not specifically included as this technology has not demonstrated feasibilities in that *** review is roughly divided into two slightly separated topics,the first on meso-and microoptics and the second on optics with nanoscale *** AM of precision optics is still in its infancy with many unanswered questions,the references cited on this exciting topic demonstrate an enabling technology with almost unlimited *** are many high quality reviews of AM processes of non-optical components,hence they are not the focus of this *** main purpose of this review is to start a conversion on optical fabrication based on information about 3D AM methods that has been made available to date,with an ultimate long-term goal of establishing new optical manufacturing methods that are low cost and highly precise with extreme flexibility.

关键词： additive manufacturing precision optics microlenses gratings diffractive optical

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Long-range precipitation forecasts using paleoclimate reconstructions in the western United States

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Journal of Mountain Science 2016年第4期13卷 614-632页

作者： Christopher allen CARRIER Ajay KALRA Sajjad AHMAD Department of Civil and Environmental Engineering University of NevadaLas Vegas4505 S.Maryland ParkwayLas VegasIVV89154-4015USA Development Review Division Clark County Public Works500 S.Grand Central ParkwayLas VegasNV 89155USA Department of Civil and Environmental Engineering Southern Illinois University1230 Lincoln DriveCarbondaleIL 62901-6603USA

Long-range precipitation forecasts are useful when managing water *** oscillations have been shown to influence *** to a longer cycle of some of the oscillations,a short instrumental record is a limitation in using them for long-range precipitation *** influence of oscillations over precipitation is observable within paleoclimate reconstructions;however,there have been no attempts to utilize these reconstructions in precipitation forecasting.A data-driven model,KStar,is used for obtaining long-range precipitation forecasts by extending the period of record through the use of reconstructions of *** is a nearest neighbor algorithm with an entropy-based distance ***-atmospheric oscillation reconstructions include the El Nino-Southern Oscillation(ENSO),the Pacific Decadal Oscillation(PDO),the North Atlantic Oscillation(NAO),and the Atlantic Multi-decadal Oscillation(AMO).Precipitation is forecasted for 20 climate divisions in the western United States.A 10-year moving average is applied to aid in the identification of oscillation phases.A lead time approach is used to simulate a one-year forecast,with a 10-fold cross-validation technique to test the *** are used from 1658-1899,while the observed record is used from *** model is evaluated using mean absolute error(MAE),root mean squared error(RMSE),RMSE-observations standard deviation ratio(RSR),Pearson's correlation coefficient(R),NashSutcliffe coefficient of efficiency(NSE),and linear error in probability space(LEPS) skill score(SK).The role of individual and coupled oscillations is evaluated by dropping oscillations in the *** results indicate 'good' precipitation estimates using the KStar *** modeling technique is expected to be useful for long-term water resources planning and management.

关键词：降水预报古气候重建美国西部太平洋年代际振荡大气振荡均方根误差平均绝对误差驱动模型

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Airway function throughout the lifespan: Pediatric origins of adult respiratory disease

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Pediatric Investigation 2019年第4期3卷 236-244页

作者： Julian Lewis allen Division of Pulmonary Medicine The Perelman School of Medicine at the University of Pennsylvania and The Children's Hospital of PhiladelphiaPhiladelphiaPAUSA

Chronic obstructive pulmonary disease(COPD)is a leading cause of disability and death of adults in the USA and *** environmental factors such as smoking and air pollution are major contributors to COPD,pediatric respiratory disease and more specifically early childhood wheezing are frequent predisposing *** is therefore possible that aggressive prevention and treatment of childhood respiratory illness may modify adult COPD *** article reviews some of the physiological factors that may explain the pediatric origins of childhood lung *** such factor is the"tracking"of normal lung function which occurs with *** maximal expiratory flow volume(MEFV)curve is an ideally suited tool to monitor tracking of airway function over the lifespan,as its relative effort independence makes it highly *** of the MEFV curve has demonstrated that individuals with similar lung volumes can have large differences in maximal flows,reflecting a disconnection between airway and lung growth("dysanapsis").Less than average airway size due to dysanaptic airway growth or airway remodeling may be independent risk factors for the development of COPD and the asthma/COPD overlap syndrome in adult *** are intriguing early data suggesting that perhaps at least some of this risk is modifiable by improving asthma control with inhaled corticosteroids and minimizing asthma exacerbations.

关键词： Chronic obstructive pulmonary disease(COPD) Asthma Asthma/COPD overlap syndrome Maximal expiratory Flow volume curve flow limitation equal pressure point Wavespeed theory Childhood origins Lung function tracking Dysanapsis Airway remodeling Prevention

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Adaptively Controlled Hybrid Welding Using a High Brightness Laser

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稀有金属材料与工程 2011年第S4期40卷 1-5页

作者： C.M.allen P.A.Hilton TWI Ltd Granta ParkGreat AbingtonCambridgeCB21 6ALUnited Kingdom

Hybrid laser-MAG welding with real-time adaptive control has been *** welding conditions have been developed to produce ISO 13919-1 class B (stringent) quality butt welds between 8mm thickness steel plates,using a 5kW *** Yb fibre laser combined with conventional arc welding equipment.A laser vision seam tracking system has enabled a 7-axis robot,manipulating the hybrid welding head,to track butt joints in real time during *** laser vision system has also provided information on the variations in joint fit-up,in particular the width of any gaps,or height of any mismatches *** information has then been used to automatically adjust the robot position or speed,or arc welding parameters,depending on the fit-up *** this way,the tolerance of the hybrid process has been augmented,producing stringent quality welds over a wider range of joint fit-up cases than when using fixed conditions alone.

关键词： hybrid welding steel adaptive control fit-up tolerance

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Protoliths of enigmatic Archaean gneisses established from zircon inclusion studies:Case study of the Caozhuang quartzite,***,China

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Geoscience Frontiers 2014年第4期5卷 445-455页

作者： allen P.Nutman Ronni Maciejowski Yusheng Wan GeoQuEST Research Centre School of Earth & Environmental SciencesUniversity of Wollongong Beijing SHRIMP Center Institute of GeologyChinese Academy of Geological Sciences

A diverse suite of Archaean gneisses at Huangbaiyu village in the North China Craton, includes rare fuchsite-bearing （Cr-muscovite） siliceous rocks - known as the Caozhuang quartzite. The Caozhuang quartzite is strongly deformed and locally mylonitic, with silica penetration and pegmatite veining common. It contains abundant 3880-3600 Ma and some Palaeoarchaean zircons. Because of its siliceous nature, the presence of fuchsite and its complex zircon age distribution, it has until now been accepted as a （mature） quartzite. However, the Caozhuang quartzite sample studied here is feldspathic. The shape and cathodoluminescence petrography of the Caozhuang quartzite zircons show they resemble those found in immature detrital sedimentary rocks of local provenance or in Eoarchaean polyphase orthog- neisses, and not those in mature quartzites. The Caozhuang quartzite intra-zircon mineral inclusions are dominated by quartz,

关键词： North China CratonCaozhuang quartziteZircon inclusionsEoarchaean rocksArchaean crustal evolution

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