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Towards efficient strain engineering of 2D materials:A four-points bending approach for compressive strain

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Nano Research 2024年第6期17卷 5317-5325页

作者： Hao Li Félix Carrascoso Ana Borrás Gloria P.Moreno Francisco j.Aparicio Ángel Barranco Andrés Castellanos Gómez Campus de Cantoblanco Instituto de Ciencia de Materiales de MadridC.Sor Juana Inés de la Cruz328049 MadridSpain Nanotechnology on surfaces and Plasma Lab Instituto de Ciencia de Materiales de Sevilla(CSIC-Universidad de Sevilla).C/Americo Vespucio 49E-41092 SevilleSpain Departamento de Física Aplicada I Escuela Politécnica SuperiorUniversidad de Sevillac/Virgen deÁfrica 7E-41011 SevilleSpain

strain engineering,as a powerful strategy to tune the optical and electrical properties of two-dimensional(2D)materials by deforming their crystal lattice,has attracted significant interest in recent years.2D materials can sustain ultra-high strains,even up to 10%,due to the lack of dangling bonds on their surface,making them ideal brittle *** remarkable mechanical resilience,together with a strong strain-tunable band structure,endows 2D materials with a broad optical and electrical response upon ***,strain engineering based on 2D materials is restricted by their nanoscale and strain quantification *** this study,we have modified a homebuilt three-points bending apparatus to transform it into a four-points bending apparatus that allows for the application of both compressive and tensile strains on 2D *** approach allows for the efficient and reproducible construction of a strain system and minimizes the buckling effect caused by the van der Waals interaction by adamantane encapsulation *** results demonstrate the feasibility of introducing compressive strain on 2D materials and the potential for tuning their optical and physical properties through this approach.

关键词： uniaxial compressive strain polymer encapsulation differential reflectance spectroscopy exciton tunability

A new approach to pedestal differentiation for soil loss estimation-a case study from a burnt area in north-central Portugal

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journal of Forestry Research 2024年第3期35卷 45-54页

作者： Frank G.A.Verheijen Martinho A.s.Martins sergio A.Prats jan j.Keizer Centre for Environmental and Marine studies(CEsAM) Department Environment and PlanningUniversity of Aveiro3810-193 AveiroPortugal Mediterranean Institute for Agriculture Environment and Development(MED-CHANGE)Institute for Advanced Studies and ResearchUniversity of EvoraPolo da MitraAp.947006-554 EvoraPortugal GeoBiociencias Geotecnologias E Geoengenharias(GEOBIOTEC)Department Environment and PlanningUniversity of Aveiro3810-193 AveiroPortugal

soil pedestals have long been used as qualitative indicators of soil splash *** rangelands,plant-capped pedestals,generally grass tussocks,have also been used to quantitatively estimate soil loss since the first half of the twentieth *** agricultural lands,forests,and bad-lands,stone-capped pedestals have been used as qualitative and semi-quantitative indicators of active,'extreme'*** work has been reported on using capstone pedestal data for quantifying soil *** postulate that three distinct capstone pedestal types may be present in any given location and that a detailed analysis of a pedestal height histogram may be used to recognize their *** analysis can subsequently inform if soil loss can be reliably estimated and if so,which of the existing methods using pedestal height data will provide more accurate *** three proposed capstone pedestal types are:(1)neo-pedestals formed underneath surface stones exposed by(partial)removal of the soil surface cover;(2)endo-pedestals formed underneath stones that were buried in the soil but have been exposed by erosion;and(3)phoenix-pedestals formed underneath stones from collapsed *** the pedestal height histogram of any given location,a skew to smaller heights may indicate the existence of endo-and/or phoenix-pedestals,which may be revealed as a bi-(or tri)modal distribution when using a smaller bin *** concept was applied to a case study where soil loss had been monitored for control plots and mulched plots during a 5-year period following wildfire in a eucalypt *** measured pedestal heights and used methods to quantitatively assess soil loss from soil pedestal data in the available *** pedestal data at the end of the 5-year period under or overestimated soil loss in the control treatment,with results ranging from 60 to 115%of measured soil loss,depending on the *** is postulated that phoenix-and endo-pedestals may be a driving fact

关键词： soil pedestals Mulch Wildfire soil erosion Char

structural effects induced by dialysis-based purification of carbon nanomaterials

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Nano Materials science 2024年第4期6卷 475-483页

作者： A.D.Veloso A.M.Ferraria A.M.Botelho do Rego A.s.Viana a.j.s.fernand.s A.j.Fielding R.A.Videira M.C.Oliveira CQ-VR and Chemistry Department University of Trás-os-Montes e Alto Douro BsIRG iBB-Institute for Bioengineering and BiosciencesDepartment of Chemical Engineeringand Associate Laboratory i4HB-Institute for Health and BioeconomyInstituto Superior TécnicoUniversidade de Lisboa Centro de Química Estrutural Institute of Molecular SciencesDepartamento de Química e BioquímicaFaculdade de CiênciasUniversidade de Lisboa I3N and Physics Department University of AveiroCampus de Santiago Faculty of science Pharmacy and Biomolecular SchoolLiverpool John Moores University REQUIMTE/LAQV Laborat orio de FarmacognosiaDepartamento de QuímicaFaculdade de Farm aciaUniversidade do Porto

Dialysis plays a crucial role in the purification of nanomaterials but its impact on the structural properties of carbon nanomaterials was never ***,a carbon-based nanomaterial generated electrochemically in potassium phosphate buffer,was characterized before and after dialysis against pure *** is shown that dialysis affects the size of the carbon domains,structural organization,surface functionalization,oxidation degree of carbon,and grade of ***,dialysis drives the nanomaterial organization from discrete roundish carbon domains,with sizes ranging from 70 to 160 nm,towards linear stacking structures of small nanoparticles （surface groups evolve into more oxidized carbon groups （e.g.,ketone and ester groups）.Investigation of the as-prepared nanomaterial by electron paramagnetic resonance （EPR） revealed a resonance signal consistent with carbon-oxygen centred ***,this study brings to light the selective affinity of the carbon nanomaterial under study to capture Na+ions,a property greatly enhanced by the dialysis process,and its high ability to trap oxygen,particularly before *** findings open new perspectives for the application of carbon-based nanomaterials and raise awareness of the importance of structural changes that can occur during the purification of carbon-based nanomaterials.

关键词： Nanocarbon surface functionalization NMR XPs Hydrophilic carbon Paramagnetic

Complexed amino acid minerals ***-glycinate chelated minerals:Impact on the performance of old laying hens

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Animal Nutrition 2024年第1期16卷 395-408页

作者： Marcos j.B.santos Maria C.M.M.Ludke Leandro M.silva Carlos B.V.Rabello Mércia R.Barros Fabiano s.Costa Clariana s.santos jamille s.s.Wanderley Department of Animal science Rural Federal University of PernambucoRecifePEBrazil Department of Veterinary science Rural Federal University of PernambucoRecifePEBrazil

The present study was to evaluate the effect of trace minerals(Zn,Mn,and Cu)from complexed amino acid minerals(ZMCAA)and bis-glycinate chelated minerals(ZMCGly)in laying hen diets on performance,internal and external egg quality,yolk mineral deposition,intestinal morphometry,and bone *** 78 to 98 weeks of age,400 White LsL-Lite strain laying hens were distributed in a randomized design with 4 treatments with 10 replicates per *** were distributed in a 2×2 factorial arrangement using either Zn,Mn,and Cu of ZMCAA or ZMCGly source at 2 levels:low(20,20,and 3.5 mg/kg of Zn,Mn,and Cu,respectively)or high(40,40,and 7 mg/kg of Zn,Mn,and Cu,respectively).The analysis of variance was performed,and in cases where differences were observed,the means were compared using Tukey?s test(Psource and level of trace mineral supplementation had a significant impact on the performance of laying *** fed ZMCAA had higher egg production(P=0.01),egg weight(P=0.02),egg mass(P=0.01),and lower feed conversion ratio(P=0.05)compared to those fed *** ZMCAA supplementation showed higher albumen height(P=0.01),albumen weight(P=0.01),and eggshell thickness(Psition of Zn(Ps greater for hens received *** weight(P=0.04)and bone densitometry(Psmall intestine,ZMCAA resulted in longer villi(P=0.02)and shorter crypt depth(P=0.01)in the *** and ileum measurements were influenced by the level and source of trace minerals(Ps fed ZMCAA exhibited superior performance,egg quality,deposition of trace minerals in the egg yolk,and bone density compared to hens fed *** this study,older laying hens supplemented with ZMCAA at lower levels demonstrated adequate levels of supplementation.

关键词： Bis-glycinates Metal-amino acids Radiodensity Trace minerals

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Compressive property and energy absorption characteristic of interconnected porous Mg-Zn-Y alloys with adjusting Y addition

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journal of Magnesium and Alloys 2024年第1期12卷 171-185页

作者： j.A.Liu s.j.Liu B.Wang W.B.sun X.j.Liu Z.W.Han College of Materials science and Engineering Key Laboratory of Automobile Materials(Ministry of Education)Jilin UniversityChangchun 130022PR China Key Laboratory of Bionic Engineering(Ministry of Education) College of Biological and Agricultural EngineeringJilin UniversityChangchun130022PR China Weihai Institute for Bionics-jilin University Weihai 264205PR China

In this study,interconnected porous Mg-2Zn-xY alloys with different phase compositions were prepared by various Y additions(x=0.4,3,and 6 wt.%)to adjust the compressive properties and energy absorption *** characterization methods were then applied to identify the microstructure of the porous Mg-Zn-Y and describe the details of the second *** tests were performed at room temperature(RT),200℃,and 300℃to study the impact of the Y addition and testing temperature on the compressive properties of the porous *** experimental results showed that a high Y content promotes a microstructure refinement and increases the volume fraction of the second *** the Y content increases,different Mg-Zn-Y ternary phases appear:I-phase(Mg_(3)Zn_(6)Y),W-phase(Mg_(3)Zn_(3)Y_(2)),and LPsO phase(Mg_(12)ZnY).When the Y content ranges between 0.4%and 6%,the compressive strength increases from 6.30MPa to 9.23 MPa,and the energy absorption capacity increases from 7.33 Mj/m^(3)to 10.97 Mj/m^(3)at RT,which is mainly attributed to the phase composition and volume fraction of the second ***,the average energy absorption efficiency is independent of the Y *** addition,the compressive deformation behaviors of the porous Mg-Zn-Y are altered by the testing *** compressive strength and energy absorption capacity of the porous Mg-Zn-Y decrease due to the softening effect of the high temperature on the *** deformation behaviors at different temperatures are finally observed to reflect the failure mechanisms of the struts.

关键词： Porous magnesium Rare earth elements Microstructure Compressive behavior Energy absorption characteristic

The CCD instrument background of the sMILE sXI

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Earth and Planetary Physics 2024年第1期8卷 15-24页

作者： M.W.j.Hubbard O.Hetherington D.j.Hall T.W.Buggey s.Parsons T.Arnold A.Holland C.Pagani s.sembay Centre for Electronic Imaging The Open UniversityMilton KeynesMK76AAUK X-ray and Observational Astronomy Group Department of Physics&AstronomyUniversity of LeicesterLE17RHUK

The EsA and CAs sMILE mission orbit is highly elliptical and will pass through multiple radiation *** soft X-ray Imager(sXI)instrument aboard has a radiation shutter door designed to close when the surrounding radiation flux is *** shutter door will close when passing below an altitude threshold to protect against trapped particles in the Earth’s Van Allen ***,two radiation environments can be approximated based on the shutter door position:open and *** instrument background for the CCDs(Charge-Coupled Devices)that form the focal plane array of the sXI were evaluated for the two *** to the correlation of the space environment with the solar cycle,the solar minima and maxima,the background was also evaluated at these two *** results demonstrated that the highest instrument background will occur during solar minima due to the main contributing source being Galactic Cosmic Rays(GCRs).It was also found that the open background was highest for solar minima and that the closed background was highest during solar *** is due to the radiation shutter door acting as a scattering centre and the changes in the energy flux distribution of the GCRs between the two solar extremes.

关键词： instrument background X-ray astronomy space radiation

A hydrodynamic modelling of wave-activated bodies for wavelet marine regions

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CLEAN ENERGY 2024年第2期8卷 35-47页

作者： Peh, j. s. Muhieldeen, Mohammed W. shuaib, N. H. UCsI Univ Fac Engn Technol & Built Environm Mech Engn Dept Kuala Lumpur 56000 Malaysia MTC Engineer sdn Bhd Shah Alam Selangor Malaysia

Recently, most wave energy research has targeted sea areas with high power density under extreme wave conditions for deployment. This trend often leads to higher energy costs for wave power plants. However, many marine areas with low power density, characterized by wavelet conditions and less destructive forces than extreme wave conditions, remain underexplored. Therefore, this study aimed to propose a wave-activated body model for sea regions with wavelet conditions. The wave-activated body design process encompassed site selection, parameter determination, geometry design, comparison and performance evaluation using the ANsYs (R) AQWA model. The results indicated that the proposed device achieved the desired heave motion, with an amplitude range of 1.2 to -2.5 m, validating its potential for deployment in marine regions with wavelet conditions. Notably, while the proposed design is optimized for wavelet conditions, it was found to have potential limitations in extreme wave environments. This observation emphasizes the challenge of formulating a generalized design suitable for both conditions. Consequently, it is pivotal for wave-activated body designs to be customized based on the specific ocean conditions they target, underscoring the need for specialized designs of wave energy converters that consider the unique wave characteristics of their deployment sites. A wave-activated body is designed for energy generation in ocean regions with wavelet conditions. Hydrodynamic modelling is carried out for two locations with different wave characteristics to determine the optimum conditions for deployment. Graphical Abstract

关键词： wave energy converter south China sea renewable and sustainable energy wavelet ANsYs AQWA hydrodynamic wave-activated bodies ENERGY IMPACT

Four Late-type Galaxies with Double Radio Lobes and Properties of such Galaxies

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Research in Astronomy and Astrophysics 2024年第4期24卷 84-90页

作者： Z.s.Yuan X.Y.Gao Z.L.Wen j.L.Han National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China CAs Key Laboratory of FAsT National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China school of Astronomy and space sciences University of Chinese Academy of SciencesBeijing 100049China

The triggering mechanism for radio lobes from late-type galaxies is not fully *** samples are desired for a thorough investigation and *** utilizing the optical data from the newly released Dark Energy spectroscopic Instrument imaging surveys and the radio sources from the NRAO VLA sky survey and the Faint Images of the Radio sky at Twenty-centimeter,we identify four Late-type Galaxies with double Radio Lobes(La GRLs):j0217-3645,j0947+6220,j1412+3723 and j1736+*** previously known La GRLs,we confirm the correlation between radio power P_(1.4GHz)and stellar mass M_(*)of host ***(25/35)La GRLs belong to the blue cloud galaxies,while the newly identified cases in this work are located within the region of the red *** find a clear correlation between the differential radio power,i.e.,the offset from the P_(1.4GHz)-M_(*)relation,and the galaxy color,indicating that bluer galaxies at a fixed M_(*)tend to host more powerful radio ***,the majority(31/36)of La GRLs are either located in a galaxy group or displaying a disturbed *** suggest that all of the galaxy mass,color and surrounding environment could play important roles in triggering radio lobes in late-type galaxies.

关键词： galaxies:active galaxies:jets galaxies:spiral radio continuum:galaxies

Inflow and outflow permeability tests in a very soft clay under low stresses

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journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3270-3283页

作者： j.W.s.Vargas F.A.B.Danziger F.R.Lopes T.Lunne Federal University of Rio de janeiro Rio de JaneiroBrazil Norwegian Geotechnical Institute OsloNorway

In situ inflow and outflow permeability tests with the BAT probe at sarapuíII soft clay test site are presented.A description of the BAT permeability test is provided,discussing its advantages and shortcomings,especially in the case of very soft clays under low *** pressures were monitored during probe installation and were found to be slightly lower than piezocone u2 pore pressures,consistent with the position of the *** role of filter tip saturation was investigated after the usual saturation procedure provided an unsatisfactory pore pressure response during probe *** show that the vacuum saturation procedure provides adequate response during installation and increases the reliability of the coefficient of permeability determination in early *** inflow and outflow tests yielded similar results,indicating that careful execution of the test can lead to good test repeatability regardless of the loading *** sequences of alternated inflow and outflow tests have yielded similar results,indicating that soil reconsolidation and filter clogging were negligible in the tests *** are presented concerning the relationship between index parameters and the in situ coefficient of permeability for sarapuíII clay,which plot outside the range of existing databases.

关键词： Permeability test soft clay BAT probe Inflow and outflow tests