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Rangeland hillslope lengths:A case study at the Walnut Gulch Experimental Watershed,southeastern Arizona

International Soil and Water Conservation Research 2022年第4期10卷 597-609页

作者： Li Li mark A.Nearing Philip Heilman Mary H.Nichols D.P.Guertin C.j.Williams School of Natural Resources and the Environment University of ArizonaTucsonAZ85705USA USDA-Agricultural Research Service Southwest Watershed Research CenterTucsonAZ85719USA

Rangeland hillslopes provide much of the sediment supplied to channel systems and their lengths exert a fundamental constraint on hillslope diffusive ***,information regarding lengths of rangeland hillslopes,and how best to estimate them,is *** this study,three groups of watersheds(10 in total)were selected from the Walnut Gulch Experimental Watershed according to their geology,soil and vegetation *** 1 watersheds were at lower elevations dominated by shrubs,Group 3 were at high elevations dominated by grass,and Group 2 were mixed shrub and *** hillslope lengths were calculated from 1 m-resolution DEMs using three methods:a flow routing algorithm,slope-area relationships,and inverted relationship with drainage *** that characterize the current watersheds,including Hack's exponent and coefficient,watershed shape coefficient,channel concavity and steepness,and surface roughness,were quantified and related to hillslope *** shows:(1)estimated hillslope lengths were different for the three methods and between the three groups of watersheds;(2)hillslope lengths that measured from the flow routing algorithm for the ten selected watersheds primarily ranged from 30 to 100 m,with a median value of 63.0 m,which was 20%e50%greater than those derived from slope-area plots or drainage densities;(3)hillslope lengths estimated from the flow routing method were greater in Group 3 watersheds than in Group 2 and then in Group 1 *** attributed these differences in hillslope lengths to the historic epeirogenic pulses,watershed and drainage network morphology,and differences in vegetation characteristics;(4)measured hillslope lengths from the flow routing algorithm were best correlated with hillslope relief,then surface roughness,channel steepness and *** results would benefit the applications of hydrological and erosion models in rangelands.

关键词： Rangeland hillslope Slope length Drainage density Slope-area relationship Hillslope hydrology

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Revealing the residual stress distribution in laser welded Eurofer97 steel by neutron diffraction and Bragg edge imaging

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journal of Materials Science & Technology 2022年第19期114卷 249-260页

作者： Bin Zhu Nathanael Leung Winfried Kockelmann Saurabh Kabra Andrew jLondon Michael Gorley mark jWhiting Yiqiang Wang Tan Sui School of Mechanical Engineering Sciences University of SurreyGuildfordSurrey GU27XHUnited Kingdom Science and Technology Facilities Council(STFC)Rutherford Appleton Laboratory ISIS FacilityHarwell OX110QXUnited Kingdom United Kingdom Atomic Energy Authority Culham Centre for Fusion EnergyCulham Science CentreAbingdonOxon OX143DBUnited Kingdom

Eurofer97 steel is a primary structural material for applications in fusion reactors. Laser welding is a promising technique to join Eurofer97 plasma-facing components and overcome remote handling and maintenance challenges. The interaction of the induced residual stress and the heterogeneous microstructure degrades the mechanical performance of such fusion components. The present study investigates the distribution of residual stress in as-welded and post-heat treated Eurofer97 joints. The mechanistic connections between microstructure, material properties, and residual stress are also studied. Neutron diffraction is used to study the through-thickness residual stress distribution in three directions,and neutron Bragg edge imaging(NBEI) is applied to study the residual strain in high spatial *** microstructures and micro-hardness are characterised by electron backscatter diffraction and nanoindentation, respectively. The M-shaped residual stress distribution through the thickness of the as-welded weldment is observed by neutron diffraction line scans over a region of 1.41 × 10 mm^(2). These profiles are cross-validated over a larger area(∼56 × 40 mm^(2)) with the higher spatial resolution by NBEI. The micro-hardness value in the fusion zone of the as-welded sample almost doubles from 2.75 ± 0.09 GPa to 5.06 ± 0.29 GPa due to a combination of residual stress and cooling-induced martensite. Conventional post weld heat treatment(PWHT) is shown to release ∼90% of the residual stress but not fully restore the microstructure. By comparing its hardness with that of stress-free samples, it is found that the microstructure is the primary contribution to the hardening. This study provides insight into the prediction of structural integrity for critical structural components of fusion reactors.

关键词： Laser-welded Eurofer97 steel Residual stress Neutron diffraction Neutron Bragg edge imaging Nanoindentation EBSD

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Assessing ecological and physiological costs of melanism in North American Papilio glaucus females: two decades of dark morph frequency declines

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Insect Science 2020年第3期27卷 583-612页

作者： j.mark Scriber Department of Entomology Michigan State UniversityEast LansingMichiganUSA McGuire Center for Lepidoptera and Biodiversity Florida Museum of Natural HistoryUniversity of FloridaGainesvilleFloridaUSA

Polymorphisms for melanic form of insects may provide various selective ***,melanic alleles may have significant/subtle pleiotrophic“costs.”Several potential pleiotrophic effects of the W(=Y)‐linked melanism gene in Papilio glaucus L.(Lepidoptera)showed no costs for melanic versus yellow in adult size,oviposition preferences,fecundity,egg viability,larval survival/growth rates,cold stress tolerance,or postdiapause emergence *** selection(males choosing yellow rather than mimetic dark females)had been suggested to provide a balanced polymorphism in ***,but spermatophore counts in wild females and direct field tethering studies of size‐matched pairs of virgin females(dark and yellow),show that male preferences are random or frequency‐dependent from Florida to Michigan,providing no yellow counter‐*** frequency declines of dark(melanic/mimetic)females in *** populations are shown in several major populations from Florida(27.3°N latitude)to Ohio(38.5°N).Summer temperatures have increased significantly at all these locations during this time(1999–2018),but whether dark morphs may be more vulnerable(in any stage)to such climate warming remains to be *** potential reasons for the frequency declines in mimetic females are discussed:(i)genetic introgression of Z‐linked melanism suppressor genes from ***(R&j)and the hybrid species,***(Pavulaan&Wright),(ii)differential developmental incompatibilities,or Haldane effects,known to occur in hybrids,(iii)selection against intermediately melanic(“dusty”)females(with the W‐linked melanic gene,b+)which higher temperatures can cause.

关键词： climate warming ecology of melanism incomplete mimicry pleiotrophic costs

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HUNCHEST-Ⅱ有利于向早期肺癌检测转变：全国筛查计划的最终结果

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国际医学放射学杂志 2024年第4期 499-499页

作者： A.Kerpel-Fronius Z.Megyesfalvi Z.markóczy D.Solymosi P.Csányi j.Tisza 沈枨

摘要目的低剂量CT(LDCT)的应用提升了肺癌筛查的效能，并有助于降低肺癌的全球死亡率。报告匈牙利最大的基于人群的LDCT筛查项目HUNCHEST-Ⅱ的最终结果，

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Integrating ancient patterns and current dynamics of insect-plant interactions＂ Taxonomic and geographic variation in herbivore specialization

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Insect Science 2010年第6期17卷 471-507页

作者： j. mark Scriber Department of Entomology Michigan State University East Lansing Michigan McGuire Center for Lepidoptera and Biodiversity Florida Museum of Natural History University of Florida Gainesville Florida USA

The search for pattern in the ecology and evolutionary biology of insect-plant associations has fascinated biologists for centuries. High levels of tropical （tow-latitude） plant and insect diversity relative to poleward latitudes and the disproportionate abundance of host-specialized insect herbivores have been noted. This review addresses several aspects of local insect specialization, host use abilities （and loss of these abilities with specialization）, host-associated evolutionary divergence, and ecological （including ＂hybrid＂） speciation, with special reference to the generation of biodiversity and the geographic and taxonomic identification of ＂species borders＂ for swallowtail butterflies （Papilionidae）. From ancient phytochemically defined angiosperm affiliations that trace back millions of years to recent and very local specialized populations, the Papilionidae （swallowtail butterflies） have provided a model for enhanced tmderstanding of localized ecological patterns and genetically based evolutionary processes. They have served as a useful group for evaluating the feeding specialization/physiological efficiency hypothesis. They have shown how the abiotic （thermal） environment interacts with host nutritional suitability to generate ＂voltinisrn/suitability＂ gradients in specialization or preference latitudinally, and geographical mosaics locally. Several studies reviewed here suggest strongly that the oscillation hypothesis for speciation does have considerable merit, but at the same time, some species-level host specializations may lead to evolutionary dead-ends, especially with rapid environmental/habitat changes involving their host plants. Latitudinal gradients in species richness and degree of herbivore feeding specialization have been impacted by recent developments in ecological genetics and evolutionary ecology. Localized insect- plant associations that span the biospectrum from polyphenisms, polymorphisms, biotypes, demes, host races, to cryptic speci

关键词： evolutionary dead-ends key innovations latitudinal gradients oscillation hypothesis of speciation polyspecialists preference/performance specialization/physiological efficiency hypothesis voltinism-suitability hypothesis

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A review of refinery complexity applications

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Petroleum Science 2017年第1期14卷 167-194页

作者： mark j. Kaiser Center for Energy Studies Louisiana State UniversityEnergy Coast and Environment Building Baton RougeLA 70803 USA

Refinery complexity quantifies the sophistication and capital intensity of a refinery and has found widespread application in facility classification, cost estimation, sales price models, and other uses. Despite the ubiquity and widespread use of refining complexity, however, surprisingly little material has been written on its applications. The pur- pose of this review is to describe the primary applications of refinery complexity and some recent extensions. A secondary purpose of this review is to provide a framework that unifies complexity applications and suggests avenues for future research. Examples illustrate the applications considered.

关键词： Cost estimation Functional complexityInverse problem Replacement cost Refineryclassification Sales price models

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Modelling of grinding mechanics:A review

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Chinese journal of Aeronautics 2023年第7期36卷 25-39页

作者： Qingyu MENG Bing GUO Qingliang ZHAO Hao Nan LI mark jjACKSON Barbara SLINKE Xichun LUO Center for Precision Engineering School of Mechatronics EngineeringHarbin Institute of TechnologyHarbin 150001China School of Aerospace The University of Nottingham NingboNingbo 315100China School of Integrated Studies College of Technology and AviationKansas State UniversitySalinaKS 67401USA Department of Mechanical and Aerospace Engineering University of California DavisDavisUSA Centre for Precision Manufacturing DMEMUniversity of StrathclydeGlasgowUK

Grinding is one of the most widely used material removal methods at the end of many process *** force is related to almost all grinding parameters,which has a great influence on material removal rate,dimensional and shape accuracy,surface and subsurface integrity,thermodynamics,dynamics,wheel durability,and machining system *** that grinding force is related to almost all grinding parameters,grinding force can be used to detect grinding wheel wear,energy calculation,chatter suppression,force control and grinding process *** prediction of grinding forces is important for optimizing grinding parameters and the structure of grinding machines and *** there are substantial research papers on grinding mechanics,a comprehensive review on the modeling of grinding mechanics is still absent from the *** fill this gap,this work reviews and introduces theoretical methods and applications of mechanics in grinding from the aspects of modeling principles,limitations and possible future trendencies.

关键词： Force modeling Grinding Grinding mechanics Macro force Micro force Model application

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Impacts of climate warming on hybrid zone movement： Geographically diffuse and biologically porous ＂species borders＂

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Insect Science 2011年第2期18卷 121-159页

作者： j. mark Scriber Department of Entomology Michigan State University East Lansing Michigan McGuire Center for Lepidoptera and Biodiversity Flonda Museum of Natural History University of Florida Gainesville Florida USA

The ecology and evolutionary biology of insect-plant associations has real- ized extensive attention, especially during the past 60 years. The classifications （categorical designations） of continuous variation in biodiversity, ranging from global patterns （e.g., lat- itudinal gradients in species richness/diversity and degree of herbivore feeding specialization） to localized insect-plant associations that span the biospectrum from polyphenisms, polymorphisms, biotypes, demes, host races, to cryptic species, remain academically contentious. Semantic and biosystematic （taxonomical） disagreements sometimes detract from more important ecological and evolutionary processes that drive diversification, the dynamics of gene flow and local extinctions. This review addresses several aspects of insect specialization, host-associated divergence and ecological （including ＂hybrid＂） speciation, with special reference to the climate warming impacts on species borders of hybridiz- ing swallowtail butterflies （Papilionidae）. Interspecific hybrid introgression may result in collapse of multi-species communities or increase species numbers via homoploid hybrid speciation. We may see diverging, merging, or emerging genotypes across hybrid zones, all part of the ongoing processes of evolution. Molecular analyses of genetic mosaics and genomic dynamics with ＂divergence hitchhiking＂, combined with ecological, ethological and physiological studies of＂species porosity＂, have already begun to unveil some answers for some important ecological/evolutionary questions. （i） How rapidly can host-associated divergence lead to new species （and why doesn＇t it always do so, e.g., resulting in ＂incom- plete＂ speciation）？（ii） How might ＂speciation genes＂ function, and how/where would we find them？（iii） Can oscillations from specialists to generalists and back to specialists help explain global diversity in herbivorous insects？（iv） How could recombinant interspecific hybridization lead to divergence an

关键词： cryptic species divergence hitchhiking ecologiealspeciation host associateddivergence mosaic genomes range limits recombinant hybrid species phylogeography,polyspecialists species boundaries

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Segregation of F-2 interspecific hybrid growth performance and wing color patterns relative to parental species in the Papilio machaon species group （Lepidoptera： Papilionidae）

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Insect Science 2007年第5期14卷 389-400页

作者： j. mark SCRIBER Department of Entomology Michigan State University East Lansing Michigan USA

A strange Papilio female specimen with a prominent yellow wing band type very much like P. brevicauda （and also seen in P. machaon, and P. zelicaon） was captured in the forested mountains of southwest Vermont, USA. Despite its brevicauda-like appearance, it had mt-DNA of P. polyxenes. In eastern North America the P. brevicauda （Maritime Provinces of Canada） is currently believed to reflect previous （ancient） hybridization between ancestral P. machaon and P. polyxenes. It is uncertain whether the brevicauda-like wing trait features in the odd Vermont female may be a result of some introgression of P. machaon or P. brevicauda with P. polyxenes in eastern North America as seen also in the Ozark Mountains with P. joanae. Nonetheless, the significance of wing trait analyses in relation to hybrid zones with P. polyxenes remains relevant. The segregation of wing color patterns and hostplant use abilities （efficiencies and growth rates） were examined for laboratory hand-paired F-2 hybrids of P. zelicaon ~ Papilio polyxenes relative to the parental species and primary hybrids. The black adult color pattern characterizing P. polyxenes is presumed to be inherited as a simple autosomal dominant. These hybrids were examined to determine：（i） how F-1 primary hybrid offspring perform relative to the parental types in survival, growth rates, and growth efficiencies; and （ii） whether these larval traits and the adult color patterns might be linked with wing morphology in the F-2 hybrids. While the F-1 hybrids grew as well as the P. polyxenes parent （P. zelicaon was significantly less efficient and slower in growth than either of these）, we could not convincingly determine whether the growth performances of the F-2 segregants were linked with the parental wing patterns.

关键词： hybrid swarms feeding efficiencies autosomai trait genetics Papilio polyxenes,Papilio zelicaon Papilio brevicauda

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Upgradation of Heavy Crude Oil Via Hydrodynamic Cavitation Through Variations in Asphaltenes

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China Petroleum Processing & Petrochemical Technology 2022年第2期24卷 23-33页

作者： Li Kang Han Haibo Lei jie Wang Youhe Li Dekun mark j.Rood Fazle Subhan Yan Zifeng State Key Laboratory of Heavy Oil Processing China University of PetroleumQingdao 266580China Luoyang R&D Center of Technology of Sinopec Engineering(Group)Co.Ltd. Luoyang 471003China Shandong Oil Refining Association Jinan 250013China Department of Civil and Environmental Engineering University of IllinoisIL 61801USA Department of Chemistry Abdul Wali Khan University MardanMardanKPPakistan

In this work,Saudi heavy crude oil(SHCO)was upgraded by the hydrodynamic cavitation *** collapse of cavitation bubbles instantly produces extreme conditions such as high temperature,pressure,and jet flow and strong shear forces,which can play a significant role in the upgradation *** results revealed that the viscosity and Conradson carbon residue of SHCO decreased from 13.61 to 7.22 mm^(2)/s and from 7.16%to 6.48%,*** boiling point distillation findings showed that the vacuum residue(VR)decreased by 1%.Atmospheric-pressure photoionization Fourier-transform ion cyclotron resonance mass spectrometry,X-ray diffraction,dynamic light scattering,Fourier-transform infrared spectroscopy,and scanning electron microscopy were employed to characterize the molecular composition,crystalline structure,asphaltene aggregate particle size distribution,functional groups,and morphology,respectively,to understand the effects of hydrodynamic cavitation on *** obtained results demonstrate that hydrodynamic cavitation upgradation reduced the interaction forces between the asphaltene molecules,weakening the crystalline structure of the asphaltene aggregates,reducing the degree of association of the aromatic compounds in SHCO and asphaltenes,and decreasing the average particle *** delayed coking properties of the VR were further investigated,and the cavitation treatment was found to decrease the coke yield by 1.85%and increase the liquid and gas yields by 1.52%and 0.33%,***,hydrodynamic cavitation can effectively enhance the processing performance of crude oil by improving the properties and structural characteristics of asphaltenes.

关键词： hydrodynamic cavitation heavy oil upgradation asphaltene crystalline structure particle size distribution agglomeration force

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