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mechanisms behind the environmental sensitivity of carbon fiber reinforced polytetrafluoroethylene(PTFE)

Friction 2024年第5期12卷 997-1015页

作者： Pontus JOHANSSON P.mARKLUND m.bjORLING Y.SHI Division of machine Element LuleåUniversity of TechnologyLuleåSE-97187Sweden

Carbon fiber reinforced polytetrafluoroethylene (CF/PTFE) composites are known for their exceptional tribological performance when sliding against steel or cast iron in inert gas environments. Compared to experiments in humid air, about an order of magnitude lower wear rate and several times lower coefficient of friction have been reported for tests conducted in dry nitrogen and hydrogen. moreover, trace moisture has been shown to affect the friction and wear significantly of this tribosystem, although a possible effect of oxygen cannot be ruled out due to uncertainties regarding the oxygen concentrations. While several studies have pointed out the environmental sensitivity of CF/PTFE, the understanding of the underlying mechanisms are very limited. The objective of this research is to investigate the individual and combined effect of oxygen and moisture on the tribological behavior of CF/PTFE sliding against steel. Additionally, this study aims to elucidate the underlying mechanisms that govern the environmental sensitivity of the system. Climate-controlled three-pin-on-disc experiments were conducted in nitrogen atmospheres at various concentrations of oxygen and moisture. The tribological results clearly demonstrate that both moisture and oxygen contribute to increased friction and wear. However, the adverse effect was much more pronounced for oxygen than moisture. A qualitative method was developed to estimate the tribofilm coverage on the CF/PTFE surface. Results showed strong correlation between high coverage of strongly adhered tribofilm and low wear rate. moreover, a loosely adhered tribofilm was observed on top of the CF/PTFE surface in presence of moisture. FTIR analysis indicated that the loosely adhered tribofilm found in the moisture-enriched environment contained a significant amount of adsorbed water, which may explain the lower coefficient of friction in presence of moisture compared to oxygen. The adsorbed water in the loosely adhered tribofilm could be an indication of moisture-driven lubricatio

关键词： polymer composite tribofilm tribochemistry atmosphere

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Conventional Geothermal Systems and Unconventional Geothermal Developments: An Overview

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Open Journal of Geology 2024年第2期14卷 196-246页

作者： maryam Khodayar Sveinbjörn björnsson Consultant and Researcher in Geosciences Reykjavík Iceland Formerly at National Energy Authority of Iceland Reykjavík Iceland

This paper provides an overview of conventional geothermal systems and unconventional geothermal developments as a common reference is needed for discussions between energy professionals. Conventional geothermal systems have the heat, permeability and fluid, requiring only drilling down to °C, normal heat flow or decaying radiogenic granite as heat sources, and used in district heating. medium-temperature (mT) 100°C - 190°C, and high-temperature (HT) 190°C - 374°C resources are mostly at plate boundaries, with volcanic intrusive heat source, used mostly for electricity generation. Single well capacities are °C - 500°C) and a range of depths (1 m to 20 Km), but lack permeability or fluid, thus requiring stimulations for heat extraction by conduction. HVAC is 1 - 2 m deep and shallow geothermal down to 500 m in wells, both capturing °C, with °C are either advanced by geothermal developers at m depth (Enhanced Geothermal Systems (EGS), drilling below brittle-ductile transition zones and under geothermal fields), or by the Oil & Gas industry (Advanced Geothermal Systems, heat recovery from hydrocarbon wells or reservoirs, Superhot Rock Geothermal, and millimeter-wave drilling down to 20 Km). Their primary aim is electricity generation, relying on closed-loops, but EGS uses fractures for heat exchange with earthquake risks during fracking. Unconventional approaches could be everywhere, with shallow geothermal already functional. The deeper and hotter unconventional alternatives are still experimental, overcoming costs and technological challenges to become fully commercial. meanwhile, the conventional geothermal resources remain the most proven opportunities for investments and development.

关键词： Conventional Geothermal Systems Unconventional Geothermal Developments Shallow and Deep Closed-Loops Enhanced Geothermal Systems Supercritical and millimeter-Wave Drilling

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Application of novel constrained friction processing method to produce fine grained biomedical mg-Zn-Ca alloy

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Journal of magnesium and Alloys 2024年第2期12卷 516-529页

作者： Ting Chen Banglong Fu Junjun Shen Uceu F.H.R.Suhuddin björn Wiese Yuanding Huang min Wang Jorge F.dos Santos Jean Pierre Bergmann Benjamin Klusemann Solid State materials Processing Institute of Material MechanicsHelmholtz-Zentrum HereonMax-Planck-Str.1Geesthacht 21502Germany Functional magnesium materials Institute of Metallic BiomaterialsHelmholtz-Zentrum HereonMax-Planck-Str.1Geesthacht 21502Germany Shanghai Key Laboratory of materials Laser Processing and modification Shanghai Jiao Tong UniversityDongchuan Road 800Shanghai 200240China Applied materials and manufacturing Energy and Environment DivisionPacific Northwest National LaboratoryPO Box 999RichlandWA 99352USA Production Technology Group Technisiche Universität IlmenauGustav-Kirchhoff-Platz 2Ilmenau 98693Germany Institute for Production Technology and Systems Leuphana University of LüneburgUniversitätsallee 1Lüneburg 21335Germany

In order to obtain mg alloys with fine microstructures and high mechanical performances,a novel friction-based processing method,name as“constrained friction processing(CFP)”,was investigated.Via CFP,defect-free mg-Zn-Ca rods with greatly refined grains and high mechanical properties were produced.Compared to the previous as-cast microstructure,the grain size was reduced from more than 1 mm to around 4μm within 3 s by a single process cycle.The compressive yield strength was increased by 350%while the ultimate compressive strength by 53%.According to the established material flow behaviors by“tracer material”,the plastic material was transported by shear deformation.From the base material to the rod,the material experienced three stages,i.***.deformation by the tool,upward flow with additional tilt,followed by upward transportation.The microstructural evolution was revealed by“stop-action”technique.The microstructural development at regions adjacent to the rod is mainly controlled by twinning,dynamic recrystallization(DRX)as well as particle stimulated nucleation,while that within the rod is related to DRX combined with grain growth.

关键词： Constrained friction processing magnesium alloys microstructure mechanical properties Grain refinement Plastic deformation

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more abundant and healthier meat:will the mSTN editing epitome empower the commercialization of gene editing in livestock?

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Science China(Life Sciences) 2022年第2期65卷 448-450页

作者： Xiaolong Wang björn Petersen Key Laboratory of Animal Genetics Breeding and Reproduction of Shaanxi ProvinceCollege of Animal Science and TechnologyNorthwest A&F UniversityYangling 712110China Institute of Farm Animal Genetics Friedrich-Loeffler-Institute(FLI)Mariensee 31535Germany

In recent years,various gene-edited crops and livestock have been developed to find rapid and unconventional solutions to boost agriculture,animal breeding,environmental sustain-ability,and animal welfare.In the animal production field,significant gene-edited livestock with economic beneficial traits,like the mSTN-edited double muscles,can be com-mercialized on a large scale to benefit more people with real need.Nutritional demand for animal proteins increases an-nually with improvement of living conditions in modern societies and developing countries.Additionally,the number of people with special needs for healthier meat(with high-protein and low-fat)is growing(e.g.,elderly patients with cardio/cerebrovascular diseases).With steady global en-vironmental deterioration,increasing human population,growing food demand,continuous disease outbreaks,and concerns regarding animal welfare。

关键词： abundant crops breeding

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Search for the doubly heavy baryons Ωbc~0 and Ξbc~0 decaying to Λc~+π~- and Ξc~+π~-

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Chinese Physics C 2021年第9期45卷 14-25页

作者： R.Aaij C.Abellán Beteta T.Ackernley B.Adeva m.Adinolfi H.Afsharnia C.A.Aidala S.Aiola Z.Ajaltouni S.Akar J.Albrecht F.Alessio m.Alexander A.Alfonso Albero Z.Aliouche G.Alkhazov P.Alvarez Cartelle S.Amato Y.Amhis L.An L.Anderlini A.Andreianov m.Andreotti F.Archilli A.Artamonov m.Artuso K.Arzymatov E.Aslanides m.Atzeni B.Audurier S.Bachmann m.Bachmayer J.J.Back P.Baladron Rodriguez V.Balagura W.Baldini J.Baptista Leite R.J.Barlow S.Barsuk W.Barter m.Bartolini F.Baryshnikov J.m.Basels G.Bassi B.Batsukh A.Battig A.Bay m.Becker F.Bedeschi I.Bediaga A.Beiter V.Belavin S.Belin V.Bellee K.Belous I.Belov I.Belyaev G.Bencivenni E.Ben-Haim A.Berezhnoy *** D.Berninghoff H.C.Bernstein C.Bertella A.Bertolin C.Betancourt F.Betti Ia.Bezshyiko S.Bhasin J.Bhom L.Bian m.S.Bieker S.Bifani P.Billoir m.Birch F.C.R.Bishop A.Bitadze A.Bizzeti m.bj?rn m.P.Blago T.Blake F.Blanc S.Blusk D.Bobulska J.A.Boelhauve O.Boente Garcia T.Boettcher A.Boldyrev A.Bondar N.Bondar S.Borghi m.Borisyak m.Borsato J.T.Borsuk S.A.Bouchiba T.J.V.Bowcock A.Boyer C.Bozzi m.J.Bradley S.Braun A.Brea Rodriguez m.Brodski J.Brodzicka A.Brossa Gonzalo D.Brundu A.Buonaura C.Burr A.Bursche A.Butkevich J.S.Butter J.Buytaert W.Byczynski S.Cadeddu H.Cai R.Calabrese L.Calefice L.Calero Diaz S.Cali R.Calladine m.Calvi m.Calvo Gomez P.Camargo magalhaes A.Camboni P.Campana A.F.Campoverde Quezada S.Capelli L.Capriotti A.Carbone G.Carboni R.Cardinale A.Cardini I.Carli P.Carniti L.Carus K.Carvalho Akiba A.Casais Vidal G.Casse m.Cattaneo G.Cavallero S.Celani J.Cerasoli A.J.Chadwick m.G.Chapman m.Charles Ph.Charpentier G.Chatzikonstantinidis C.A.Chavez Barajas m.Chefdeville C.Chen S.Chen A.Chernov V.Chobanova S.Cholak m.Chrzaszcz A.Chubykin V.Chulikov P.Ciambrone m.F.Cicala X.Cid Vidal G.Ciezarek P.E.L.Clarke m.Clemencic H.V.Cliff J.Closier J.L.Cobbledick V.Coco J.A.B.Coelho J.Cogan E.Cogneras L.Cojocariu P.Collins T.Colombo L.Congedo A.Contu N.Cooke G.Coombs G.Corti C.m.Costa Sobral B.Couturier D.C.Craik J.Crkovská m.Cruz Torres R.Currie C.L.Da Silva E.Dall’Occo J.Dalseno C.D’Amb AGH-University of Science and Technology Faculty of Computer Science Electronics and Telecommunications AGH-University of Science and Technology Faculty of Physics and Applied Computer Science Aix marseille Univ CNRS/IN2P3 CPPM Budker Institute of Nuclear Physics (SB RAS) Cavendish Laboratory University of Cambridge Center for High Energy Physics Tsinghua University Centro Brasileiro de Pesquisas Físicas (CBPF) DS4DS La Salle Universitat Ramon Llull Departamento de Fisica Universidad Nacional de Colombia Department of Physics and Astronomy University of Manchester Department of Physics and Astronomy Uppsala University Department of Physics University of Oxford Department of Physics University of Warwick European Organization for Nuclear Research (CErn) Fakult?t Physik Technische Universit?t Dortmund Guangdong Provencial Key Laboratory of Nuclear Science Institute of Quantum Matter South China Normal University H.H. Wills Physics Laboratory University of Bristol Hangzhou Institute for Advanced Study UCAS Hanoi University of Science Henryk Niewodniczanski Institute of Nuclear Physics Polish Academy of Sciences Horia Hulubei National Institute of Physics and Nuclear Engineering I.Physikalisches Institut RWTH Aachen University ICCUB Universitat de Barcelona INFN Laboratori Nazionali di Frascati INFN Sezione di Bari INFN Sezione di Bologna INFN Sezione di Cagliari INFN Sezione di Ferrara INFN Sezione di Firenze INFN Sezione di Genova INFN Sezione di milano INFN Sezione di milano-Bicocca INFN Sezione di Perugia INFN Sezione di Pisa INFN Sezione di Roma La Sapienza INFN Sezione di Roma Tor Vergata Imperial College London Institut für Physik Universit?t Rostock Institute Of High Energy Physics (IHEP) Institute for High Energy Physics NRC Kurchatov Institute (IHEP NRC KI) Institute for Nuclear Research of the National Academy of Sciences (KINR) Institute for Nuclear Research of the Russian Academy of Sciences (INR RAS) Institute of Nuclear Physics Moscow State University (SINP MSU) Institute of Part

The first search for the doubly heavy Ωbc~0 baryon and a search for the Ξbc~0 baryon are performed using pp collision data collected via the LHCb experiment from 2016 to 2018 at a centre-of-mass energy of 13 TeV,corresponding to an integrated luminosity of 5.2 fb-1.The baryons are reconstructed via their decays to ∧c~+π~-andΞc~+π~-.No significant excess is found for invariant masses between 6700 and 7300 meV/c2,in a rapidity range from2.0 to 4.5 and a transverse momentum range from 2 to 20 meV/c.Upper limits are set on the ratio of the Ωbc~0 andΞbc~0 production cross-section times the branching fraction to ∧c~+π~-(Ξc~+π~-) relative to that of the ∧b~0(Ξb~0) baryon,for different lifetime hypotheses,at 95% confidence level.The upper limits range from 0.5×10-4to 2.5×10-4for theΩbc~0→∧c~+π~-(Ξbc~0→∧c~+π~-) decay,and from 1.4×10-3to 6.9×10-3for the Ωbc~0→Ξc~+π~-(Ξbc~0→Ξc~+π~-) decay,depending on the considered mass and lifetime of the Ωbc~0(Ξbc~0) baryon.

关键词： B physics quarkonium spectroscopy heavy quark production

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Influence of cerium ions on structure-dependent magnetic properties of Ba-Sr m-type hexaferrite nanocrystals

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Journal of Rare Earths 2024年第2期42卷 364-372,I0005页

作者： Ram A.Pawar Sunil m.Patange P.m.Dighe Sher Singh meena Abdullah GAl-Sehemi mehboobali Pannipara Santosh S.Jadhav Department of Physics ArtsCommerce and Science CollegeAhmednagar413711MaharashtraIndia Department of Physics Shri Krishna MahavidyalayaGunjotiDistOsmanabad413606MaharashtraIndia Padmashri Vikhe Patil College of Arts Science and CommercePravaranagarA/P.Loni(Kd)Tal.RahataDistAhmednagar413713MaharashtraIndia Solid State Physics Division Bhabha Atomic Research CentreMumbai400085MaharashtraIndia Department of Chemistry King Khalid UniversityAbha61413Saudi Arabia Department of Physics D.S.M's ArtsCommerce and Science CollegeJintur431509MaharashtraIndia

The present study is a systematic effort to investigate the structure-sensitive magnetic parameters of Ce^(3+) substituted Ba-Sr hexaferrite nanocrystals chemically formulated as Ba_(0.5)Sr_(0.5)Ce_(x)Fe_(12-x)O_(19) where x=0.0-0.2 with Δx=0.05.The hexaferrite powders were prepared using the sol-gel self-ignition route and structurally characterized by means of powder X-ray diffraction and Fourier transform infrared spectroscopy.The creation of the m-type hexaferrite phase within the synthesized samples was revealed from the Rietveld refinement of the X-ray diffractograms.The occurrence of a secondary phase of CeO_(2) was revealed within the hexaferrites for the substitution,x> 0.The refined X-ray diffraction data were utilized to compute the lattice parameters,X-ray density,and lattice parameter ratio.The crystal structure plotted from the refined XRD data reveals the occupancy of the ions at different lattice sites.The XPS data of the hexaferrite were analyzed to confirm the oxidation states of the constituent elements.The nanocrystalline nature of the hexaferrites was revealed from the crystallite sizes calculated using Scherer's formula.The analysis of FTIR spectra confirms that only a fraction of Ce^(3+)accommodated in the lattice and the remaining Ce content reside in the form of the CeO_(2) phase.The morphology of the hexaferrites was analyzed from the FESEm profiles of the ferrite samples.The magnetic behavior study was performed by analyzing the Curie temperature,hysteresis loops,and hyperfine interactions by means of susceptibility,V.S.m,and mossbauer spectroscopy,respectively.The hexaferrites with increasing coercivity,decreasing saturation magnetization,and decreasing Curie temperature are reported in the study.The substituted Ce^(3+)ions inhibit the grain growth and create lattice imperfections giving rise to hexaferrites with tuned magnetic parameters suitable for different applications.

关键词： Ba-Sr hexaferrite Ce^(3+)substitution XPS Saturation magnetization Coercivity m?ssbauer spectroscopy

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Frequency-dependent viscoelasticity effects on the wave attenuation performance of multi-layered periodic foundations

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 407-424页

作者： m.SAFI m.VAKILIFARD m.J.mAHmOODI Faculty of Civil Water&Environmental EngineeringShahid Beheshti UniversityTehran ***Iran Faculty of mechanical and Energy Engineering Shahid Beheshti UniversityTehran ***Iran

In this paper,layered periodic foundations(LPFs)are numerically examined for their responses to longitudinal and transverse modes in the time and frequency domains.Three different unit-cells,i.e.,2-layer,4-layer,and 6-layer unit-cells,comprising concrete/rubber,concrete/rubber/steel/rubber,and concrete/rubber/steel/rubber/lead/rubber materials,respectively,are taken into account.Also,the viscoelasticity behavior of the rubber is modeled with two factors,i.e.,a frequency-independent(FI)loss factor and a linear frequency-dependent(FD)loss factor.Following the extraction of the complex dispersion curves and the identification of the band gaps(BGs),the simulations of wave transmission in the time and frequency domains are performed using the COmSOL software.Subsequent parametric studies evaluate the effects of the rubber viscoelasticity models on the dispersion curves and the wave transmission for the longitudinal and transverse modes.The results show that considering the rubber viscoelasticity enhances the wave attenuation performance.moreover,the transverse-mode damping is more sensitive to the viscoelasticity model than its longitudinal counterpart.The 6-layer unit-cell LPF exhibits the lowest BG,ranging from 4.8 Hz to 6.5 Hz.

关键词： layered metamaterial periodic foundation complex dispersion curve wave transmission diagram

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Toward implantable devices for angle-sensitive,lens-less,multifluorescent,single-photon lifetime imaging in the brain using Fabry-Perot and absorptive color filters

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Light(Science & Applications) 2022年第2期11卷 197-211页

作者： Adriaan J.Taal Changhyuk Lee Jaebin Choi björn Hellenkamp Kenneth L.Shepard Columbia University-Department of Electrical Engineering 500W.120th St.Mudd 1310New York 10027 NYUSA Korea Institute of Science and Technology-Brain Science Institute 5 Hwarang-ro 14-gilSeongbuk-guSeoul 02792Republic of Korea

Implantable image sensors have the potential to revolutionize neuroscience.Due to their small form factor requirements;however,conventional filters and optics cannot be implemented.These limitations obstruct highresolution imaging of large neural densities.Recent advances in angle-sensitive image sensors and single-photon avalanche diodes have provided a path toward ultrathin lens-less fluorescence imaging,enabling plenoptic sensing by extending sensing capabilities to include photon arrival time and incident angle,thereby providing the opportunity for separability of fluorescence point sources within the context of light-field microscopy(LFm).However,the addition of spectral sensitivity to angle-sensitive LFm reduces imager resolution because each wavelength requires a separate pixel subset.Here,we present a 1024-pixel,50μm thick implantable shank-based neural imager with color-filtergrating-based angle-sensitive pixels.This angular-spectral sensitive front end combines a metal–insulator–metal(mIm)Fabry–Perot color filter and diffractive optics to produce the measurement of orthogonal light-field information from two distinct colors within a single photodetector.The result is the ability to add independent color sensing to LFm while doubling the effective pixel density.The implantable imager combines angular-spectral and temporal information to demix and localize multispectral fluorescent targets.In this initial prototype,this is demonstrated with 45μm diameter fluorescently labeled beads in scattering medium.Fluorescent lifetime imaging is exploited to further aid source separation,in addition to detecting pH through lifetime changes in fluorescent dyes.While these initial fluorescent targets are considerably brighter than fluorescently labeled neurons,further improvements will allow the application of these techniques to in-vivo multifluorescent structural and functional neural imaging.

关键词： filters lifetime angle

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Engineering of efficient visible light photocatalysts:Ti_(1-x+y)Cu_(x)La_(y)O_(2)(x=0.03;y=0,0.005,0.01) compositions

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Journal of Rare Earths 2024年第3期42卷 497-505,I0003页

作者： S.m.Yakout A.m.Youssef Inorganic Chemistry Department National Research Centre(NRC)El Buhouth StDokkiCairo12622Egypt

In dye-photocatalysis, widening the wavelengths absorption range of catalysts as well as aborting the recombination of the photoexcited charge carriers(electrons-holes pairs) are of paramount significance.In the current study, we report the photocatalytic characteristics of four compositions composed of TiO_(2),Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders for two harmful dyes(Congo red and methylene blue). The X-ray diffraction technique verified the configuration of mixed anatase and rutile phases in pure TiO_(2)and Ti_(0.97)Cu_(0.03)O_(2)powders while Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders possess anatase phase only. The changes of the band gap structure and dimensions of the unit cell volume of TiO_(2)confirm the substitution of Ti^(4+)sites by Cu^(2+)and La^(3+)ions. Remarkable widening of wavelengths absorption with formation of long absorption tails were found in TiO_(2)(3.13 e V) through insertion of La^(3+)plus Cu^(2+)ions. Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)samples exhibit a visible light band gap of 2.3 and 2.7 e V, respectively. Based on SEm images, incorporation of Cu^(2+)and La^(3+)ions influences the surface morphology of TiO_(2). The resulting Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders present enhanced photocatalytic activity towards Congo red dye degradation compared to pure one under natural solar spectrum. The best Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst exhibits superior photocatalytic activity of 96% for 10 ppm CR dye in 20 min as well as above average photocatalytic efficiency of 63% for 30 ppm CR dye in 120 min. As well, it showed acceptable photodegradation activity of 52% for 30 ppm mB solution in 140 min of sunlight irradiation. The heightened photodegradation efficiency of Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst can be clarified in terms of higher charge carriers' separation(Cu^(2+)+ e-→ Cu^(+), L

关键词： Semiconductor TiO_(2) Rare earths Congo red methylene blue Solar spectrum Photodegradation

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Free vibration and buckling analysis of polymeric composite beams reinforced by functionally graded bamboo fbers

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 543-562页

作者： H.m.FEIZABAD m.H.YAS Department of mechanical Engineering Razi UniversityKermanshah ***Iran

Natural fibers have been extensively researched as reinforcement materials in polymers on account of their environmental and economic advantages in comparison with synthetic fibers in the recent years.Bamboo fibers are renowned for their good mechanical properties,abundance,and short cycle growth.As beams are one of the fundamental structural components and are susceptible to mechanical loads in engineering applications,this paper performs a study on the free vibration and buckling responses of bamboo fiber reinforced composite(BFRC)beams on the elastic foundation.Three different functionally graded(FG)layouts and a uniform one are the considered distributions for unidirectional long bamboo fibers across the thickness.The elastic properties of the composite are determined with the law of mixture.Employing Hamilton’s principle,the governing equations of motion are obtained.The generalized differential quadrature method(GDQm)is then applied to the equations to obtain the results.The achieved outcomes exhibit that the natural frequency and buckling load values vary as the fiber volume fractions and distributions,elastic foundation stiffness values,and boundary conditions(BCs)and slenderness ratio of the beam change.Furthermore,a comparative study is conducted between the derived analysis outcomes for BFRC and homogenous polymer beams to examine the effectiveness of bamboo fibers as reinforcement materials,demonstrating the significant enhancements in both vibration and buckling responses,with the exception of natural frequencies for cantilever beams on the Pasternak foundation with the FG-◇fiber distribution.Eventually,the obtained analysis results of BFRC beams are also compared with those for carbon nanotube reinforced composite(CNTRC)beams found in the literature,indicating that the buckling loads and natural frequencies of BFRC beams are lower than those of CNTRC beams.

关键词： bamboo fiber free vibration buckling analysis functionally graded(FG)beam elastic foundation generalized differential quadrature method(GDQm)

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