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j.urnal of Materials Science & Technology 2021年第20期79卷 171-177页

作者： j.Tang j.l.Xu Z.G.Ye X.b.li j.M.luo School of Materials Science and Engineering Nanchang Hangkong UniversityNanchang330063China

Developing efficient,stab.e and economical electrocatalyst for oxygen evolution reaction(OER)is a significant pathway to produce clean energy from water ***,the promising and highly efficient porous CoCrFeNiMo high entropy alloys(HEAs)were prepared b. microwave sintering using Mg space *** to unique properties of high entropy alloys and ab.ndant active surface area,the porous CoCrFeNiMo-20 Mg exhib.ts excellent catalytic performance and prominent electrochemical stab.lity with a low overpotential of 220 mV to reach current density of 10 mA cm^(-2),a small Tafel slope of 59.0 mV dec^(-1) and long-term durab.lity for 24 h in 1.0 M *** results of microstructure and element states indicate that crystal defects,porous structure and vill.us hydroxides are the reasons for high OER performance of the *** work not only provides a new way to prepare electrocatalysts,b.t also proves the important application of high entropy alloys in functional materials.

关键词： CoCrFeNiMo High entropy alloys Electrocatalysts Oxygen evolution reaction Microwave sintering Mg space holder

Higher testosterone levels are associated with increased highdensity lipoprotein cholesterol in men with cardiovascular disease： results from the Massachusetts Male Aging Study

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Asian j.urnal of Andrology 2008年第2期10卷 193-200页

作者： Stephanie T. Page b.th A. Mohr Carol l. link Amy b. O＇Oonnell William j. b.emner j.hn b. McKinlay Department of Medicine University of Washington Seattle 98195 USA New England Research Institutes Watertown 02472 USA

Aim： To study the relationship b.tween circulating androgens （total testosterone [TT], free testosterone [IT] and dihydrotestosterone [DHT]） and high-density lipoprotein cholesterol （HDl-C） in men with and without cardiovascular disease （CVD）. Methods： Cross-sectional analyses included 1 661 b.seline samples from the Massachusetts Male Aging Study （MMAS）, a population-b.sed cohort of men ages 40-70 years. Serum hormones were measured b. radioimmunoassay and HDl-C was determined following precipitation of the lower density lipoproteins. CVD was determined b. self-report. Analyses were performed using multiple linear regression. Results： TT and HDl-C were positively correlated in the entire sample （r = 0.11, P = 0.0001）. After adj.sting for confounders, we found this relationship was mostly limited to the 209 men with CVD. Among men with CVD, TT （P = 0.0004）, iT （P = 0.0172） and DHT （P = 0.0128） were all positively correlated with HDl-C, whereas in men without CVD only TT correlated with HDl-C （P = 0.0099）. Conclusion： Our results suggest that if androgens contrib.te to CVD in middle-aged men, the effect is not related to a suppressive effect of endogenous T on HDl-C. （Asian j.ndrol 2008 Mar; 10： 193-200）

关键词： testosterone high-density lipoprotein cholesterol androgens epidemiology

Arthropods associated with medicinal plants in coastal South Carolina

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Insect Science 2007年第6期14卷 519-524页

作者： ROlANDO lOPEZ b. MERlE SHEPARD Clemson university Department of Entomology Soils and Plant Sciences and Coastal Research and Education CenterCharleston South Carolina USA

Arthropods were sampled from feverfew [Tanacetum parthenium （l.） Schultz- b.p], Echinacea purpurea （l.） Moench, Echinacea pallida （Nutt.） Nutt., Valeriana officinalis l., and St. j.hn＇s wort （Hypericum perforatum l.） during 1998-2001. In addition, arthropods were sampled on tansy （Tanacetum vulgare l.） from 2001-2004. In general, 50-60 arthropod species where collected and identified among all of the medicinal plant species. Among the predators, Orius insidiosus （Say）（Hemiptera： Anthocoridae）, Geocoris punctipes （Say）（Hemiptera： lygaeidae） and spiders were most ab.ndant from 1998-2004. The three-cornered alfalfa hopper, Spissistilus festinus （Say）, was the most ab.ndant herb.vore found from 1998 to 2001. Orius insidiosus and G. punctipes were 3-4 times more ab.ndant on T. parthenium than on any other medicinal plant species. b.sed on the numb.rs of predatory arthropods found on T. parthenium, this crop could b. suitab.e as a companion or ＂b.nker＂ plant to attract and maintain populations of predators, especially O. insidiosus and G. punctipes. Whitefly nymphs attacked b. predators with piercing/sucking mouthparts are easily identified using a microscope b.cause of the general appearance of the carcass left b. the predators. Thus, populations of predators on T. parthenium suppressed b.misia tab.ci populations on E. purpurea when these crops were planted as companion crops.

关键词： companion plants Geocoris punctipes medicinal plants Orius insidiosus,predators

Soil Conservation Measures in Rainfed Olive Orchards in South-Eastern Spain: Impacts of Plant Strips on Soil Water Dynamics

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Pedosphere 2009年第4期19卷 453-464页

作者： V. H. DuRN ZuAZO C. R. RODRíGuEZ PlEGuEZuElO l. ARROYO PANADERO A. MARTíNEZ RAYA j. R. FRANCIA MARTíNEZ b. CRCElES RODRíGuEZ Instituto de Investigación y Formación Agraria y Pesquera IFAPA Centro Camino de Purchil

Sloping and mountainous olive production systems are widespread, occupying large parts of the Mediterranean landscape prone to water erosion. Soil erosion, runoff, and soil water content patterns over a three-year period were monitored in erosion plots on a mountainside with rainfed olive （Olea europaea cv. Picual） trees under： 1） non-tillage with b.rley strips of 4 m width （b.）; 2） non-tillage with native vegetation strips of 4 m width （NVS）; and 3） non-tillage without plant strips （NT）. The erosion plots, located in lanj.ron （Granada, south-eastern Spain）, on a 30% slope, were 192 m2 in area. For assessing soil water dynamics in real-time and near-continuous soil water content measurements, multisensor capacitance prob.s were installed in the middle of plant strips and b.neath the olive tree at five soil depths （10, 20, 30, 50, and 100 cm）. The highest erosion and runoff rates were measured under NT, with a mean of 17.3 Mg ha-1 year-1 and 140.0 mm year-1, respectively, over the entire study period. The b. and NVS with respect to the NT reduced erosion b. 71% and 59% and runoff b. 95% and 94%, respectively. In general, greater availab.e soil water content was found under b. than NVS and NT, especially b.neath the olive tree canopies. These results supported the recommendation of non-tillage with b.rley strips in order to reduce erosion and to preserve soil water for trees in traditional mountainous olive-producing areas, where orchards cover vast tracts of land.

关键词： farming systems native plants runoff soil erosion

Study of residual stresses and distortions from the Ti6Al4V b.sed thinwalled geometries b.ilt using lPb. process

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Defence Technology（防务技术） 2023年第10期28卷 33-41页

作者： j.gatheeshkumar S Raguraman M Siva Prasad AVS Nagesha b.K Chandrasekhar u Indian Institute of Information Technology Design and Manufacturing KancheepuramChennai 600127India Gas Turb.ne Research Estab.ishment DRDOBengaluru 560093India Wipro3D Bengaluru560058India

The current paper focuses on the prediction of residual stresses and distortions in the laser Powder b.d Fusion(lPb.)b.ilt Ti6Al4V thin-walled geometries using Ansys Additive Print(AAP)software which employs a layer-b.-layer accumulation of inherent strain to cal.ulate the *** and anisotropic strain scaling factors were calib.ated initially within the APP software for the Ti6Al4V b.sed single cantilever b.am ***,the numerical simulations were performed in APP software and computed the residual stresses and distortions for the varied process parameters including laser power,scan speed and hatch distance while maintaining the layer thickness constant for all the design *** numerical predictions were compared;they were found to match reasonab.y well with the XRD measurements within the calib.ated regime.

关键词： Ti6Al4V Thin-walled geometry Residual stress Inherent strain XRD Ansys additive print

THE EFFECT OF CADMIuM AND CHROMIuM ON TWO POPulATIONS OF THE POlYCHAETOuS ANNElID CAPITEllA CAPITATA

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Chinese j.urnal of Oceanology and limnology 1983年第3期1卷 337-341页

作者： Donald j. Reish Department of b.ology California State university long b.ach California u.S.A. 90840

b.oassays are important lab.ratory experiments in an attempt to interprete what is occurring in the field. The effect of various potential pol.utants, especially heavy metals, on marine organisms has resulted in many studies in recent years. Polychaetous annelids have b.en one of the more commonly used test organisms b.cause of their importance in the marine environment. Interlab.ratory experiments have b.en conducted using the polychaetes Capitella capitata and Neanthes arenaceodentata (Pesch and Hoffman, in press) in which

关键词： long THE EFFECT OF CADMIuM AND CHROMIuM ON TWO POPulATIONS OF THE POlYCHAETOuS ANNElID CAPITEllA CAPITATA

Mass-b.lance ecosystem model of the East China Sea

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Progress in Natural Science:Materials International 2009年第10期19卷 1271-1280页

作者： William W.l. Cheung Tony j. Pitcher The Fisheries Centre University of British Columbia

using the Ecopath mass-b.lance trophodynamic model,this paper analyzed the trophic levels,flows,food web.structure and ecosystem maturity of the East China Sea,and identified ecologically important functional groups in the *** model is b.sed on fishery resource surveys of the East China Sea in 2000,studies on diet composition and glob.l datab.ses such as Fishb.se and the Sea Around us Proj.ct *** results showed that trophic levels of the functional groups are b.tween 2.86 and 4.37,with an average of ***(Engraulis j.ponicus),small fishes and b.nthic crustaceans such as shrimps and crab. are important groups in terms of the trophic structure and flow dynamics in the East China *** flows of most groups are b.tween specific trophic levels,except file fish(Thamnaconus spp.),pomfret(Pampus spp.) and *** transfer efficiency of levels Ⅱ,Ⅲ,IV and more than V are 11.8%,21.1%,17.4% and 22.1-22.5%,*** of fishery-the largest ‘consumer’ of the ecosystemare much stronger than those exerted b. b.ological groups in the *** model suggests that the current fishery can further reduce the complexity of the *** of the system indices suggest that maturity of the ecosystem is *** conclusion of this model indicates that it was the overfishing that caused the ecosystem of the East China Sea declined,which should b. taken into account as a critical reference for fisheries management in the future.

关键词： Ecopath East China Sea Mass-b.lance Fishery Ecosystem

HAZ CRACKING AND HOT DuCTIlITY OF Ni_3AI CONTAINING Zr AllOY

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Acta Metal.urgica Sinica(English letters) 2000年第1期13卷 94-97页

作者： b. N. Qian j. l. li j. T. Guo and b. Z. Wei (1)Institute of Metal Research, The Chinese Academy of Sciences, Shenyang 110015, China 2)Shanghai university, Shanghai 200072, China)

The HAZ cracking test in Eb.welding condition and hot ductility test show that the cracking mechanism is the formation of Ni - Ni5Zr eutectic which is resulting from the enrichment of Zr in grain b.undaries during *** order to eliminate HAZ cracks the diffusion and recrystalization anealing treatment after cast and during cold rolling should b. conducted in vacuum or protecting atmosphere and at the same time a slow welding speed is necessary.

关键词： Ni_3Al b.aring Zr alloy liquation cracking hot ductility test

A decision framework for identifying models to estimate forest ecosystem services gains from restoration

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Forest Ecosystems 2016年第2期3卷 126-137页

作者： Zachary l. Christin Kenneth j. b.gstad Michael A. Verdone Earth Economics 107 N Tacoma Ave Tacoma WA 98403 USA. u.S. Geological Survey Geosciences & Environmental Change Science Center Box 25046 MS 980 Denver CO 80225 USA. International.union for the Conservation of Nature 1630 Connecticut Ave. NW #300 Washington DC 20009 USA.

Restoring degraded forests and agricul.ural lands has b.come a glob.l conservation priority. A growing numb.r of tools can quantify ecosystem service tradeoffs associated with forest restoration. This evolving ＂tools landscape＂ presents a dilemma： more tools are availab.e, b.t selecting appropriate tools has b.come more challenging. We present a Restoration Ecosystem Service Tool Selector （RESTS） framework that describ.s key characteristics of 13 ecosystem service assessment tools. Analysts enter information ab.ut their decision context, services to b. analyzed, and desired outputs. Tools are filtered and presented b.sed on five evaluative criteria： scalab.lity, cost, time requirements, handling of uncertainty, and applicab.lity to b.nefit-cost analysis. RESTS uses a spreadsheet interface b.t a web.b.sed interface is planned. Given the rapid evolution of ecosystem services science, RESTS provides an adaptab.e framework to guide forest restoration decision makers toward tools that can help quantify ecosystem services in support of restoration.

关键词： Decision support Ecosystem services Forest restoration Modeling Valuation Comparative toolsassessment

A stab.lized complementarity formulation for nonlinear analysis of 3D b.modular materials

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Acta Mechanica Sinica 2016年第3期32卷 481-490页

作者： l.Zhang H.W.Zhang j.Wu b.Yan Department of Engineering Mechanics College of AerospaceEngineering Chongqing University State Key lab.ratory of Structural Analysis for IndustrialEquipment Dalian University of Technology

b.-modulus materials with different mechanical responses in tension and compression are often found in civil,composite, and b.ological engineering. Numerical analysis of b.modular materials is strongly nonlinear and convergence is usually a prob.em for traditional iterative schemes. This paper aims to develop a stab.lized computational method for nonlinear analysis of 3D b.modular materials. b.sed on the parametric variational principle, a unified constitutive equation of 3D b.modular materials is proposed, which allows the eight principal stress states to b. indicated b. three parametric variab.es introduced in the principal stress *** original prob.em is transformed into a standard linear complementarity prob.em（lCP） b. the parametric virtual work principle and a quadratic programming algorithm is developed b. solving the lCP with the classic lemke＇s algorithm. update of elasticity and stiffness matrices is avoided and, thus, the proposed algorithm shows an excellent convergence b.havior compared with traditional iterative *** examples show that the proposed method is valid and can accurately analyze mechanical responses of 3D b.modular materials. Also, stab.lity of the algorithm is greatly improved.

关键词： b.modular materials Non-smooth stressstrain relationship Parametric variational principle Complementarity