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An atomistic approach for the structural and electronic properties of twisted bilayer graphene-boron nitride heterostructures

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npj Computational Materials 2022年第1期8卷 687-696页

作者： Min Long pierre a.pantaleón Zhen Zhan Francisco Guinea JoseÁngel Silva-Guillén Shengjun Yuan Key Laboratory of Artificial Micro-and nano-structures of Ministry of Education and School of Physics and Technology Wuhan UniversityWuhan430072China Imdea nanoscience C/Faraday 928015MadridSpain Donostia International Physics Center Paseo Manuel de Lardizábal 420018San SebastiánSpain Ikerbasque Basque Foundation for Science48009BilbaoSpain Wuhan Institute of Quantum Technology Wuhan430206China

Twisted bilayer graphene(TBG)has taken the spotlight in the condensed matter community since the discovery of correlated phases.In this work,we study heterostructures of TBG and hexagonal boron nitride(hBn)using an atomistic tight-binding model together with semi-classical molecular dynamics to consider relaxation effects.The hBn substrate has significant effects on the band structure of TBG even in the case where TBG and hBn are not aligned.Specifically,the substrate induces a large mass gap and strong pseudo-magnetic fields that break the layer degeneracy.Interestingly,such degeneracy can be recovered with a second hBn layer.Finally,we develop a continuum model that describes the tight-binding band structure.Our results show that a real-space tight-binding model in combination with semi-classical molecular dynamics is a powerful tool to study the electronic properties of moiréheterostructures,and to explain experimental results in which the effect of the substrate plays an important role.

关键词： boron electronic twisted

Decomposition mechanisms of nuclear-grade cationic exchange resin by advanced oxidation processes:Statistical molecular fragmentation model and DFT calculations

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Journal of Environmental Sciences 2024年第1期135卷 433-448页

作者： Xiang Meng pierre Désesquelles Lejin Xu Department of nuclear Engineering and Technology School of Energy and Power EngineeringHuazhong University of Science&TechnologyWuhan 430074China CnRS Laboratoire de Physique des Gaz et des PlasmasUniversitéParis-SaclayOrsay 91405France State Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The treatment and disposal of radioactive waste are presently facing great challenges.Spent ion exchange resins have become a focus of attention due to their high production and serious environmental risks.In this paper,a simplified model of cationic exchange resin is proposed,and the degradation processes of cationic resin monomer initiated by hydroxyl radicals(·OH)are clarified by combining statistical molecular fragmentation(SMF)model and density functional theory(DFT)calculations.The prediction of active sites indicates that the S-O bonds and the C-S bond of the sulfonic group are more likely to react during the degradation.The meta-position of the sulfonic group on the benzene ring is the most active site,and the benzene ring without the sulfonic group has a certain reactivity.The C11-C14 and C17-C20 bonds,on the carbon skeleton,are the most easily broken.It is also found that dihydroxy addition and elimination reactions play a major role in the process of desulfonation,carbon skeleton cleavage and benzene ring separation.The decomposition mechanisms found through the combination of physical models and chemical calculations,provide theoretical guidance for the treatment of complex polycyclic aromatic hydrocarbons.

关键词： Cationic exchange resin Statistical molecular fragmentation model Density functional theory Hydroxyl radical Decomposition mechanism

Cavity optomechanics with directionally squeezed light

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 181-182页

作者： pierre Meystre Department of Physics and College of Optical Sciences University of ArizonaTucson 85721USA

It is well understood that the Heisenberg uncertainty principle imposes a fundamental limit on the precision of quantum measurements.One way to get around this difficulty is to exploit quantum states that minimize the uncertainty on the observable of interest,increasing in the process the uncertainty on the conjugate observable.Squeezed states of the electromagnetic field.

关键词： field observable quantum

Re-evaluation of recent research on metabolic utilization of energy in poultry: Recommendations for a net energy system for broilers

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Animal nutrition 2024年第1期16卷 62-72页

作者： Jean noblet Aye-Cho Tay-Zar Shu-Biao Wu Pairat Srichana pierre Cozannet pierre-Andre Geraert Mingan Choct InRAE Charoen Pokphand Foods Public Company Limited (CPF) School of Environmental and Rural Science University of New England Adisseo France S.A.S.

Different energy systems have been proposed for energy evaluation of feeds for domestic animals. The oldest and most commonly used systems take into account the fecal energy loss to obtain digestible energy(DE), and fecal, urinary and fermentation gases energy losses to calculate metabolizable energy(ME). In the case of ruminants and pigs, the net energy(nE) system, which takes into account the heat increment associated with the metabolic utilization of ME, has progressively replaced the DE and ME systems over the last 50 years. For poultry, apparent ME(AME) is used exclusively and nE is not yet used widely. The present paper considers some important methodological points for measuring nE in poultry feeds and summarizes the available knowledge on nE systems for poultry. nE prediction equations based on a common analysis of three recent studies representing a total of 50 complete and balanced diets fed to broilers are proposed; these equations including the AME content and easily available chemical indicators have been validated on another set of 30 diets. The equations are applicable to both ingredients and complete diets. They rely primarily on an accurate and reliable AME value which then represents the first limiting predictor of nE value. Our analysis indicates that nE would be a better predictor of broiler performance than AME and that the hierarchy between feeds is dependent on the energy system with a higher energy value for fat and a lower energy value for protein in an nE system. Practical considerations for implementing such an nE system from the commonly used AME or AMEn(AME adjusted for zero nitrogen balance) systems are presented. In conclusion, there is sufficient information to allow the implementation of the nE concept in order to improve the accuracy of feed formulation in poultry.

关键词： Poultry Feed evaluation net energy Energy system

Immunobiodiversity:Conserved and specific immunity across land plants and beyond

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Molecular Plant 2024年第1期17卷 92-111页

作者： Baptiste Castel Karima El Mahboubi Christophe Jacquet pierre-Marc Delaux Laboratoire de Recherche en Sciences Végétales(LRSV) Universitéde ToulouseCNRSUPSToulouse INPCastanet-TolosanFrance

Angiosperms represent most plants that humans cultivate,grow,and eat.However,angiosperms are only one of five major land plant lineages.As a whole lineage,plants also include algal groups.All these clades represent a tremendous genetic diversity that can be investigated to reveal the evolutionary history of any given mechanism.In this review,we describe the current model of the plant immune system,discuss its evolution based on the recent literature,and propose future directions for the field.In angiosperms,plant–microbe interactions have been intensively studied,revealing essential cell surface and intracellular immune receptors,as well as metabolic and hormonal defense pathways.Exploring diversity at the genomic and functional levels demonstrates the conservation of these pathways across land plants,some of which are beyond plants.On basis of the conserved mechanisms,lineage-specific variations have occurred,leading to diversified reservoirs of immune mechanisms.In rare cases,this diversity has been harnessed and successfully transferred to other species by integration of wild immune receptors or engineering of novel forms of receptors for improved resistance to pathogens.We propose that exploring further the diversity of immune mechanisms in the whole plant lineage will reveal completely novel sources of resistance to be deployed in crops.

关键词： evolution MPMI immunity plant evoMPMI symbiosis

Monitoring absolute vertical land motions and absolute sea-level changes from GPS and tide gauges data over French Polynesia

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Geodesy and Geodynamics 2024年第1期15卷 13-26页

作者： Xianjie Li Jean-pierre Barriot Bernard Ducarme Marania Hopuare Yidong Lou Geodesy Observatory of Tahiti University of French PolynesiaFaa'a 98702French Polynesia Catholic University of Louvain Georges Lemaître Centre for Earth and Climate Research(ELI)1348 Louvain-la-NeuveBelgium GnSS Research Center Wuhan UniversityWuhan 430079China State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhan 430079China

In this study,we estimate the absolute vertical land motions at three tidal stations with collocated Global navigation Satellite System(GnSS)receivers over French Polynesia during the period 2007-2020,and obtain,as ancillary results,estimates of the absolute changes in sea level at the same locations.To verify our processing approach to determining vertical motion,we first modeled vertical motion at the International GnSS Service(IGS)THTI station located in the capital island of Tahiti and compared our estimate with previous independent determinations,with a good agreement.We obtained the following estimates for the vertical land motions at the tide gauges:Tubuai island,Austral Archipelago-0.92±0.17 mm/yr,Vairao village,Tahiti Iti:-0.49±0.39 mm/yr,Rikitea,Gambier Archipelago-0.43±0.17 mm/yr.The absolute variations of the sea level are:Tubuai island,Austral Archipelago 5.25±0.60 mm/yr,Vairao village,Tahiti Iti:3.62±0.52 mm/yr,Rikitea,Gambier Archipelago 1.52±0.23 mm/yr.We discuss these absolute values in light of the values obtained from altimetric measurements and other means in French Polynesia.

关键词： GPS Tide gauges Sea level changes Vertical land motion

A Review on Sources,Extractions and Analysis Methods of a Sustainable Biomaterial:Tannins

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Journal of Renewable Materials 2024年第3期12卷 397-425页

作者： Antonio Pizzi Marie-pierre Laborie Zeki Candan LERMAB University of LorraineFaculty of SciencesBlvd des AiguillettesNancy54000France Chair of Forest Biomaterials Institute of Earth and Environmental SciencesUniversity of FreiburgFreiburgGermany Freiburg Materials Research Center Alberst Ludwig University of FreiburgFreiburg79104Germany Department of Forest Products Engineering Faculty of ForestryIstanbul UniversitySariyerIstanbul34473Turkey

Condensed and hydrolysable tannins are non-toxic natural polyphenols that are a commercial commodity industrialized for tanning hides to obtain leather and for a growing number of other industrial applications mainly to substitute petroleum-based products.They are a definite class of sustainable materials of the forestry industry.They have been in operation for hundreds of years to manufacture leather and now for a growing number of applications in a variety of other industries,such as wood adhesives,metal coating,pharmaceutical/medical applications and several others.This review presents the main sources,either already or potentially commercial of this forestry by-materials,their industrial and laboratory extraction systems,their systems of analysis with their advantages and drawbacks,be these methods so simple to even appear primitive but nonetheless of proven effectiveness,or very modern and instrumental.It constitutes a basic but essential summary of what is necessary to know of these sustainable materials.In doing so,the review highlights some of the main challenges that remain to be addressed to deliver the quality and economics of tannin supply necessary to fulfill the industrial production requirements for some materials-based uses.

关键词： Tannins flavonoids sources extraction methods analysis methods

Prediction of net energy of feeds for broiler chickens

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Animal nutrition 2024年第1期16卷 241-250页

作者： Aye-Cho Tay-Zar Manoosak Wongphatcharachai Pairat Srichana pierre-André Geraert Jean noblet Charoen Pokphand Foods Public Company Limited (CPF) Adisseo France S.A.S. InRAE

net energy(nE) enables the prediction of more accurate feed energy values by taking into account the heat increment which is approximately 25% of apparent metabolizable energy(AME) in poultry.nevertheless, application of nE in poultry industry has not been practiced widely. To predict the nE values of broiler diets, 23 diets were prepared by using 13 major ingredients(wheat, corn, paddy rice,broken rice, cassava pellets, full-fat soybean, soybean meal, canola meal, animal protein, rice bran, wheat bran, palm kernel meal and palm kernel oil). The diets were formulated in order to meet the birds' requirements and get a wide range of chemical compositions(on DM basis; 33.6% to 55.3% for starch;20.8% to 28.4% for CP, 2.7% to 10.6% for ether extract [EE] and 7.0% to 17.2% for nDF), with low correlations between these nutrients and low correlations between the inclusion levels of ingredients allowing for the calculation of robust prediction equations of energy values of diets or ingredients. These diets were fed to Ross 308 broilers raised in 12 open-circuit respiratory chambers from 18 to 23 d of age(4 birds per cage) and growth performance, diet AME content and heat production were measured, and dietary nE values were calculated. The trial was conducted on a weekly basis with 12 diets measured each week(1per chamber), 1 of the 23 diets(reference diet) being measured each week. Each diet was tested at least 8times. In total, 235 energy balance data values were available for the final calculations. Growth performance, AME(15.3 MJ/kg DM on average) and AME/GE(79.4% on average) values were as expected. The nE/AME value averaged 76.6% and was negatively influenced by CP and nDF and positively by EE in connection with efficiencies of AME provided by CP, EE and starch for nE of 73%, 87% and 81%,respectively. The best prediction equation was: nE =(0.815 × AME)—(0.026 × CP) +(0.020 × EE)—(0.024 × nDF) with nE and AME as MJ/kg DM, and CP, EE and nDF as % of DM. The nE prediction equations from this study agree with other recen

关键词： net energy Broiler Poultry Feed evaluation Energy system

EP Aquarii:A new Picture of the Circumstellar Envelope

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Research in Astronomy and Astrophysics 2024年第3期24卷 83-105页

作者： Pham T.nhung Do T.Hoai pierre Darriulat Pham Tuan-Anh Pham n.Diep nguyen B.ngoc Tran T.Thai Department of Astrophysics Vietnam National Space CenterVietnam Academy of Science and Technology18Hoang Quoc VietNghia DoCau GiayHa Noivietnam

new analyses of earlier ALMA observations of oxygen-rich AGB star EP Aquarii are presented,which complete a previously published analysis and offer a different interpretation of the morpho-kinematics of the circumstellar envelope.The birth of the equatorial density enhancement(EDE)is shown to occur very close to the star where evidence for rotation has been obtained.Close to the star and where outflows have been observed:their interaction with the gas of the nascent EDE is seen to play an important role in the development of the wind and the evolution of its radial velocity from 8 to 10 km s^(-1) on the polar symmetry axis to~2 km s^(-1) at the equator.It implies complex morpho-kinematics:making reliable interpretations with reasonable confidence is difficult.In particular,it questions an earlier interpretation implying the presence of a white dwarf companion orbiting the star at an angular distance of -0″4 from its center.It proposes instead an interpretation in terms of a standard mass ejection associated with a shock wave leaving a void of emission in its wake.High Doppler velocity wings are seen to consist of two components,the upper velocity end of the global wind,reaching above±12 km s^(-1),and an effective line broadening,confined within 200 mas from the center of the star,reaching above±20 km s^(-1) and interpreted as caused by the pattern of shock waves resulting from the interaction between stellar pulsation and convective cell partition.

关键词： stars AGB and post-AGB-(stars) circumstellar matter-radio lines stars