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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

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

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

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

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

Rumen microbial degradation of bromoform from red seaweed(Asparagopsis taxiformis)and the impact on rumen fermentation and methanogenic archaea

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Journal of Animal Science and Biotechnology 2024年第1期15卷 412-426页

作者： Pedro Romero Alejandro Belanche Elisabeth Jiménez Rafael Hueso Eva Ramos-Morales Joan King Salwen Ermias Kebreab David R.y.ñez-Ruiz Estacion Experimental del Zaidin Consejo Superior de Investigaciones Cientificas(CSIC)Profesor Albareda 1Granada 18008Spain Department of Animal Production and Food Sciences University of ZaragozaMiguel Servet 177Saragossa 50013Spain Blue Ocean Barns Inc. Redwood CityCAUSA Department of Animal Science University of CaliforniaDavisCA 95618USA

Background The red macroalgae Asparagopsis is an effective methanogenesis inhibitor due to the presence of halogenated methane(CH_(4))analogues,primarily.bromoform(CHBr_(3)).This study.aimed to investigate the degradation process of CHBr3 from A taxiformis in the rumen and whether this process is *** in vitro batch culture sy.tem was used according to a 2×2 factorial design,assessing two A taxiformis inclusion rates[0(CTL)and 2%DM diet(AT)]and two diets[high-concentrate(HC)and high-forage diet(HF)].Incubations lasted for 72 h and samples of headspace and fermentation liquid were taken at 0,0.5,1,3,6,8,12,16,24,48 and 72 h to assess the pattern of degradation of CHBr_(3) into dibromomethane(CH_(2)Br_(2))and fermentation ***,an in vitro experiment with pure cultures of seven methanogens strains(Methanobrevibacter smithii,Methanobrevibacter ruminantium,Methanosphaera stadtmanae,Methanosarcina barkeri,Methanobrevibacter millerae,Methanorhermobacter wolfei and Methanobacterium mobile)was conducted to test the effects of increasing concentrations of CHBr3(0.4,2,10and 50μmol/L).Results The addition of AT significantly.decreased CH_(4) production(P=0.002)and the acetate:propionate ratio(P=0.003)during a 72-h *** concentrations of CHBr_(3) showed a rapid decrease with nearly.90%degraded within the first 3 h of *** the contrary.CH_(2)Br_(2) concentration quickly.increased during the first 6 h and then gradually.decreased towards the end of the *** CHBr_(3) degradation nor CH_(2)Br_(2) sy.thesis were affected by.the ty.e of diet used as substrate,suggesting that the fermentation rate is not a driving factor involved in CHBr_(3)*** in vitro culture of methanogens showed a dose-response effect of CHBr3 by.inhibiting the growth of ***,***,***,***,***,***,and *** The present work demonstrated that CHBr_(3) from *** is quickly.degrad

关键词： Bromoform metabolism Dibromomethane metabolism Methane mitigation Methanogens Rumen microbiota Seaweed

Seismic attribute and well-log analy.is for channel characterization in the upper San Andres and Gray.urg formations of the Midland Basin,Texas

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Energy Geoscience

Energy.Geoscience 2024年第2期5卷 263-278页

作者： Sumit Verma Esra y.lçın y.lmaz Laura Ortiz Sanguino Justin y.ndell Miles A.Henderson Robert C.Trentham Department of Geosciences The University of Texas Permian BasinOdessaTXUSA School of Geosciences The University of OklahomaNormanOKUSA

The Permian Basin is one of the most prolific,and currently.one of the most active,oil and gas basins in the *** Lower Permian strata in the Permian Basin have produced more than 14 billion barrels of oil(BBO),making it the largest volume of hy.rocarbon in the *** in the Midland Basin during late Leonardian through early.Guadalupian(ca.272-269 Ma)resulted in progradation of shelf edge and ultimately.closure of the basin by.Middle Permian *** analy.ed a merged seismic survey.covering parts of the Permian Basin(i.e.,Central Basin Platform and Midland Basin)in Andrews,Ector,and Midland Counties,*** seismic survey.and well logs show the presence of gently.dipping(ca.1°)clinoforms in the Upper San Andres and Gray.urg Formations on the eastern edge of the Central Basin Platform and western Midland *** seismic attributes,curvature,and spectral decomposition identify.low sinuosity.slope channels oriented north-south,but such channels do not appear bey.nd the *** shelf edge shifts from north to south during deposition of the Upper San Andres and Gray.urg *** identify.five basinward shifts noted by.the migration of the shelf edge toward the basin center and the presence of channel features along the depositional *** petrophy.ical analy.is indicates that channels cut into carbonate rocks and are filled by.siliciclastic sediments;this interpretation is supported by.the most negative curvature anomalies along the channel axes caused by.the differential compaction between the carbonate and siliciclastic *** are a few channels with a northwest-southeast strike,which matches the direction of the Concho Lineament observed by.satellite *** observations are consistent with previous interpretations of the northern Midland Basin closure during Middle-Late Permian time.

关键词： Permian shelf carbonate

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

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