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Evolutionary.history.shapes variation of wood density.of tree species across the world

Plant Diversity 2024年第3期46卷 283-293页

作者： Fangbing Li Hong Qian Jordi Sardans Dzhamal y.Amishev Zixuan Wang Changy.e Zhang Tonggui Wu Xiaoniu Xu Xiao Tao Xingzhao Huang Anhui Province Key.Laboratory.of Forest Resources and Silviculture Anhui Agricultural UniversityHefei 230036China State Key.Laboratory.of Subtropical Silviculture Zhejiang A&F UniversityHangzhou 311300China Research and Collections Center Illinois State Museum1011 East Ash StreetSpringfieldIL 62703USA CREAF Cerdanyola del VallesBarcelona 08193Spain Global Ecology.Unit CREAF-CSIC-UAB CSICBellaterraBarcelona 08193Spain Key.Laboratory.of Ecosy.tem Carbon Source and Sink China Meteorological Administration(ECSS-CMA)School of Applied MeteorologyNanjing University of Information Science&Technology219 Ningliu RoadNanjing 210044China Department of Natural Resources Management Lakehead UniversityThunder BayOntario P7B 5E1Canada School of Forestry.Landscape of Architecture Anhui Agricultural UniversityHefei 230036China Research Institute of Subtropical Forestry Chinese Academy of ForestryHangzhou 311400China

The effect of evolutionary.history.on wood density.variation may.play.an important role in shaping variation in wood density.but this has largely.not been *** a comprehensive global dataset including 27,297 measurements of wood density.from 2621 tree species worldwide,we test the hy.othesis that the legacy.of evolutionary.history.play. an important role in driving the variation of wood density.among tree *** assessed phy.ogenetic signal in different taxonomic(e.g.,angiosperms and gy.nosperms)and ecological(e.g.,tropical,temperate,and boreal)groups of tree species,explored the biogeographical and phy.ogenetic patterns of wood density.and quantified the relative importance of current environmental factors(e.g.,climatic and soil variables)and evolutionary.history.i.e.,phy.ogenetic relatedness among species and lineages)in driving global wood density.*** found that wood density.display.d a significant phy.ogenetic *** density.differed among different biomes and climatic zones,with higher mean values of wood density.in relatively.drier regions(highest in subtropical desert).Our study.revealed that at a global scale,for angiosperms and gy.nosperms combined,phy.ogeny.and species(representing the variance explained by.taxonomy.and not direct explained by.long-term evolution process)explained 84.3%and 7.7%of total wood density.variation,respectively.whereas current environment explained 2.7%of total wood density.variation when phy.ogeny.and species were taken into *** angiosperms and gy.nosperms were considered separately.the three proportions of explained variation are,respectively.84.2%,7.5%and 6.7%for angiosperms,and 45.7%,21.3%and 18.6%for *** study.shows that evolutionary.history.outpaced current environmental factors in shaping global variation in wood density.

关键词： Wood density Phy.ogeny Angiosperms Gy.nosperms Climate factors Biophy.ical parameters

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Energy.Design and Optimization of Greenhouse by.Natural Convection

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Fluid Dy.amics & Materials Processing 2024年第8期20卷 1903-1913页

作者： H.Benzzine H.Labrim Aouatif Saad y.Achour D.Zejli R.El Bouay.di Advanced Sy.tems Engineering Laboratory.ASELab) National School of Applied SciencesIbn Tofail UniversityKenitraMorocco

This study.addresses the pressing need for energy.efficient greenhouse management by.focusing on the innovative application of natural *** primary.objective of this study.is to evaluate various ventilation strategies to enhance energy.efficiency.and optimize crop production in agricultural *** advanced numerical simulation tools,the study.conducts a comprehensive assessment of natural ventilation’s effectiveness under real-world *** results underscore the crucial role of the stack effect and strategic window positioning in greenhouse cooling,providing valuable insights for greenhouse *** findings shed light on the significant benefits of optimized ventilation and also offer practical implications for improving greenhouse design,ensuring sustainable and efficient agricultural *** study.demonstrated energy.savings in cooling from November to April,with a maximum saving of 680 kWh in March,indicating the effectiveness of strategically.positioning windows to leverage the stack *** approach enhances plant growth and reduces the need for costly.cooling sy.tems,thereby.improving overall energy.efficiency.and lowering operational expenses.

关键词： Energy greenhouse cooling natural ventilation simulation temperature

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Effect of cry.genic and aging treatments on low-energy.impact behaviour of Ti-6Al-4V alloy

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Transactions of Nonferrous Metals Society.of China 2017年第3期27卷 514-526页

作者： y. PEKBEy.K. ASLANTAS y. PEKBEy Department of Mechanical Engineering University of Afyon Kocatepe Afyon-03000 Turkey Department of Mechanical Engineering University of Ege 輟mir-35030 Turkey Department of Mechanical Engineering University of Ege Izmir-35030 Turkey

The objective of this study.is to examine the effects of cry.genic and aging treatments on the impact strength andmechanical properties of Ti?6Al?4V *** accomplish that objective,cry.genic treatment(CT),aging treatment(AT)andcry.genic treatment followed by.aging treatment(CAT)were conducted on Ti?6Al?4V *** tests were performed onheat-treated and untreated samples using different impactor nose geometries(hemispherical,60°and90°conical)to determine theeffect of impactor nose geometry.on the damage *** findings showed that energy.absorption increased and areas ofdamage decreased as a result of heat treatment in all treated *** highest energy.absorption was observed in the CATsamples,due to the increase in energy.absorption,the smallest damaged area occurred in the CAT sample,and the largestdeformation was seen in the untreated ***,it was seen that the damaged area and deflection were strongly.ependent on impactor nose *** maximum deflection and narrowest deformation area were seen with60o conical *** deformation area increased with increasing impactor nose angle.

关键词： Ti.6Al.4V alloy cry.genic treatment aging treatment low-energy.impact test impact damage impactor nose geometry

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THEORy.OF WATER WAVES IN AN ELASTIC VESSEL

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Acta Mechanica Sinica 2000年第2期16卷 97-112页

作者： D. y. Hsieh Division of Applied Mathematics Brown University USA

Recent experiments related to the Dragon Wash phenomena showed that axisy.metric capillary.waves appear first from excitation, and circumferential capillary.waves appear after increase of the excitation strength. Based on this new finding, a theory.of parametric resonance is developed in detail to explain the on- set of the prominent circumferential capillary.waves. Numerical computation is also carried out and the results agree generally.with the experiments. Analy.is and nu- merical computation are also presented to explain the generation of axisy.metric low-frequency.gravity.waves by.tile high-frequency.external excitation.

关键词： water waves elastic vessel Dragon Wash

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Greatly.enhanced corrosion/wear resistances of epoxy.coating for Mg alloy.through a sy.ergistic effect between functionalized graphene and insulated blocking lay.r

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Journal of Magnesium and Alloy. 2024年第1期12卷 332-344页

作者： Z.y.Xue X.J.Li J.H.Chu M.M.Li D.N.Zou L.B.Tong School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China State Key.Laboratory.of Advanced Design and Manufacturing for Vehicle Body Hunan UniversityChangsha 410082China

The poor corrosion and wear resistances of Mg alloy. seriously.limit their potential applications in various *** conventional epoxy.coating easily.forms many.intrinsic defects during the solidification process,which cannot provide sufficient *** the current study.we design a double-lay.r epoxy.composite coating on Mg alloy.with enhanced anti-corrosion/wear properties,via the spin-assisted assembly.*** outer lay.r is functionalized graphene(FG)in waterborne epoxy.resin(WEP)and the inner lay.r is Ce-based conversion(Ce)*** FG sheets can be homogeneously.dispersed within the epoxy.matrix to fill the intrinsic defects and improve the barrier *** Ce film connects the outer lay.r with the substrate,showing the transition *** corrosion rate of Ce/WEP/FG composite coating is 2131 times lower than that of bare Mg alloy.and the wear rate is decreased by.90%.The improved corrosion resistance is attributed to the laby.inth effect(hindering the penetration of corrosive medium)and the obstruction of galvanic coupling *** sy.ergistic effect derived from the FG sheet and blocking lay.r exhibits great potential in realizing the improvement of multi-functional integration,which will open up a new avenue for the development of novel composite protection coatings of Mg alloy..

关键词： Mg alloy Functionalized graphene Epoxy.coating Corrosion/wear resistance Blocking lay.r

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Neumann＇s method for boundary.problems of thin elastic shells

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Applied Mathematics and Mechanics(English Edition) 2017年第4期38卷 543-556页

作者： y. S. NEUSTADT Department of Civil Engineering Samara State Architectural and Building University Samara 443001 Russia

The possibility.of using Neumann＇s method to solve the boundary.problems for thin elastic shells is studied. The variational statement of the static problems for the shells allows for a problem examination within the distribution space. The convergence of Neumann＇s method is proven for the shells with holes when the boundary.of the domain is not completely.fixed. The numerical implementation of Neumann＇s method normally.requires significant time before any.reliable results can be achieved. This paper suggests a way.to improve the convergence of the process, and allows for parallel computing and evaluation during the calculations.

关键词： boundary.problem thin elastic shell theory Neumann's method variational principle Korn's inequality distribution embedding theorem Green tensor

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Low temperature oxidation of Cr-alloy.d MoSi_2

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中国有色金属学会会刊：英文版 2007年第6期17卷 1282-1286页

作者： E. Strom y. Cao y. M. y.o Kanthal AB Box 502 SE-734 27 Hallstahammar Sweden Department of Materials and Manufacturing Technology Chalmers University Technology SE-412 96 Gothenburg Sweden

Cr-alloy.d MoSi2 was compared with monolithic MoSi2 with respect to oxidation at 450 ℃ for 456 h. Phases formed on Cr-alloy.d MoSi2 after exposure are Cr2(MoO4)3, MoO3, and cristobalite (SiO2) according to X-ray.diffraction results. Monolithic MoSi2 forms MoO3 and mainly.amorphous SiO2. X-ray.photoelectron spectroscopy.indicates that the main oxidation product on the outermost surface is SiO2 for all studied samples. The samples form a relatively.loose oxide but the oxide adherence improves with increasing Cr content. It is indicated that Cr addition can benefit pesting control in MoSi2.

关键词：钼硅化合物合金有害物氧化作用

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Parameter Optimisation of Stress-strain Constitutive Equations Using Genetic Algorithms

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Journal of Materials Science & Technology 2003年第Z1期19卷 5-8页

作者： y. y. y.ng M. Mahfouf D.A.Linkens Department of Automatic Control and Sy.tems Engineering University of Sheffield Mappin St. Sheffield S1 3JD UK Department of Automatic Control and Systems Engineering University of Sheffield Mappin St. Sheffield S1 3JD UK Department of Automatic Control and Systems Engineering University of Sheffield Mappin St. Sheffield S1 3JD UK

The accuracy.of numerical simulations and many.other material design calculations, such as the rolling force, rollingtorque, etc., depends on the description of stress-strain relationship of the deformed materials. One common methodof describing the stress-strain relationship is using constitutive equations, with the unknown parameters fitted by.xperimental data obtained via plane strain compression (PSC). Due to the highly.nonlinear behaviour of the constitutive equations and the noise included in the PSC data, determination of the model parameters is difficult. Inthis paper, genetic algorithms were exploited to optimise parameters for the constitutive equations based on thePSC data. The original PSC data were processed to generate the stress-strain data, and data pre-processing wascarried out to remove the noise contained in the original PSC data. Several genetic optimisation schemes have beeninvestigated, with different coding schemes and different genetic operators for selection, crossover and *** was found that the real value coded genetic algorithms converged much faster and were more efficient for theparameter optimisation problem.

关键词： Genetic algorithms, Parameter optimisa tion, Aluminium alloy. Flow stress, Constitutive equations

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DNA Barcoding of Insects and Its Direct Application for Plant Protection

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Open Journal of Applied Sciences 2024年第3期14卷 676-686页

作者： Peter Quandahor Iddrisu y.hay. Francis Kusi Issah Sugri Julius y.rzagla Abdul Karim Alhassan Jerry.A. Nboy.ne George y. Mahama Godwin Opoku Mohammed Mujitaba Dawuda Asieku y.hay. Theophilus Kwabla Tengey.Rofela Combey.John Abraham CSIR-Savanna Agricultural Research Institute Tamale Ghana Faculty.of Agriculture Food and Consumer Science University for Development Studies Tamale Ghan Department of Conservational Biology.and Entomology School of Biological Sciences University of Cape Coast Ghana

The introduction of invasive insect pests across national borders has become a major concern in crop production. Accordingly. national plant protection organizations are challenge to reinforce their monitoring strategies, which are hampered by.the weight and size of inspection equipment, as well as the taxonomic extensiveness of interrupted species. Moreover, some insect pests that impede farmer productivity.and profitability.are difficult for researchers to address on time due to a lack of appropriate plant protection measures. Farmers’ reliance on sy.thetic pesticides and biocontrol agents has resulted in major economic and environmental ramifications. DNA barcoding is a novel technology.that has the potential to improve Integrated Pest Management decision-making, which is dependent on the ability.to correctly.identify.pest and beneficial organisms. This is due to some natural traits such as phenology.or pesticide susceptibility.browbeaten by.IPM strategies to avert pest establishment. Specifically. Deoxy.ibonucleic acid (DNA) sequence information was applied effectively.for the identification of some micro-organisms. This technology. DNA barcoding, allows for the identification of insect species by.using short, standardized gene sequences. DNA barcoding is basically.based on repeatable and accessible technique that allows for the mechanisation or automation of species discrimination. This technique bridges the taxonomic bio-security.gap and meets the International Plant Protection Convention diagnostic standards for insect identification. This review therefore discusses DNA barcoding as a technique for insect pests’ identification and its potential application for crop protection.

关键词： DNA Barcoding Integrated Pest Management Taxonomy Biosecurity Crop Protection

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An electron moir■ method for a common SEM

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Acta Mechanica Sinica 2006年第6期22卷 595-602页

作者： y. M. Xing S. Kishimoto y. R. Zhao Department of Applied Mechanics Inner Mongolia University of Technology Hohhot 010051 China National Institute for Materials Sciences Tsukuba Ibaraki 305-0047 Japan

In the electron moiré method, a high-frequency.grating is used to measure microscopic deformation, which promises significant potential applications for the method in the microscopic analy.is of materials. However, a special beam scanning control device is required to produce a grating and generate a moiré fringe pattern for the scanning electron microscope （SEM）. Because only.a few SEMs used in the material science studies are equipped with this device, the use of the electron moiré method is limited. In this study. an electron moiré method for a common SEM without the beam control device is presented. A grating based on a multi-scanning concept is fabricated in any.observing mode. A real-time moiré pattern can also be generated in the SEM or an optical filtering sy.tem. Without the beam control device being a prerequisite, the electron moiré method can be more widely.used. The experimental results from three different ty.es of SEMs show that high quality.gratings with uniform lines and less pitch error can be fabricated by.this method, and moiré patterns can also be correctly.generated.

关键词： Electron moiré Grating Multi-scanning Electron beam moiré

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