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Science China(Information Sciences) 2024年第8期67卷 24-34页

作者： Siyuan WANG Andrey POLYAKOV Min LI Gang ZHENG driss BOUTAT INSA Centre val de Loire INRIA

The objective of the invariant ellipsoid method is to minimize the smallest invariant and attractive set of a linear control system operating under the influence of bounded external disturbances. This study extends the application of this method to address the leader-following consensus problem. Initially, a linear control protocol is designed for the multi-agent system in the absence of disturbances. Subsequently, in the presence of bounded disturbances, by employing a similar linear control protocol, a necessary and sufficient condition is introduced to derive the optimal control parameters for the multi-agent system such that the state of followers converges to and remains in a minimal invariant ellipsoid around the state of the leader.

关键词： disturbance invariant ellipsoid leader-following consensus multi-agent system

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Energy based 3d trajectory tracking control of quadrotors with model-free based on-line disturbance compensation

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Chinese Journal of Aeronautics 2018年第7期31卷 1568-1578页

作者： Yasser BOUZId Houria SIGUERdIdJANE Yasmina BESTAOUI IBISC Laboratory Université d'Evry Val d'Essonne Université Paris-Saclay L2S CentraleSupélecUniversité Paris-Saclay

In this work, a Revisited form of the so-called Model-Free Control（R-MFC） is ***, the MFC principle is employed to deal with the unknown part of a plant only（i.e., unmodeled dynamics, disturbances, etc.） and occurs beside an Interconnection and damping AssignmentPassivity Based Control（IdA-PBC） strategy. Using the proposed formulation, it is shown that we can significantly improve the performance of the control through the reshaping properties of the IdA-PBC technique. Moreover, the control robustness level is increased via a compensation of the time-varying disturbances and the unmodeled system dynamics. This on-line compensation capability is provided by the MFC principle. The problem is studied in the case of Multi-Input Multi-Output（MIMO） mechanical systems with an explicit application to a small Vertical Take-Off and Landing（VTOL） Unmanned Aerial Vehicle（UAV） where a stability analysis is also provided. Numerical simulations have shown satisfactory results, in comparison with some other control strategies, where an in-depth discussion with respect to the control performance is highlighted by considering several scenarios and using several metrics.

关键词： IdA-PBC Model-free control Nonlinear flight control Robust control Trajectory tracking

density Results in Sobolev Spaces Whose Elements Vanish on a Part of the Boundary

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Chinese Annals of Mathematics,Series B 2011年第6期32卷 823-846页

作者： Jean-Marie Emmanuel BERNARd Laboratoire Analyse et Probabitilités Université d'Evry val d'Essonne23 Boulevard de France91037 EVRYFrance

This paper is devoted to the study of the subspace of Wm＇＂ of functions that vanish on a part γ0 of the boundary. The author gives a crucial estimate of the Poincare constant in balls centered on the boundary of γ0. Then, the convolution-translation method, a variant of the standard mollifier technique, can be used to prove the density of smooth functions that vanish in a neighborhood of γ0, in this subspace. The result is first proved for m = 1, then generalized to the case where m 〉 1, in any dimension, in the framework of Lipschitz-continuous domain. However, as may be expected, it is needed to make additional assumptions on the boundary of γ0, namely that it is locally the graph of some Lipschitz-continuous function.

关键词： density results Boundary value problems Sobolev spaces

Solar-assisted photocatalytic water splitting using defective UiO-66 solids from modulated synthesis

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Nano Research 2024年第5期17卷 4134-4150页

作者： Celia M.Rueda-Navarro María Cabrero-Antonino Paula Escamilla valentín díez-Cabanes dong Fan Pedro Atienzar Belén Ferrer Ignacio Vayá Guillaume Maurin Herme G.Baldoví Sergio Navalón departamento de Química Universitat Politècnica de ValènciaCamino de Vera s/nValencia 46022Spain Instituto de Ciencia Molecular(ICMOL) Universitat de ValènciaPaterna 46980Spain ICGM Univ.MontpellierCNRSENSCMMontpellier34095France Instituto de Tecnología Química(UPV-CSIC) Universitat Politècnica de ValènciaAvenida de los Naranjos s/nValencia 46022Spain

Metal-organic frameworks(MOFs)are attracting increasing interests as photocatalysts for solar-driven hydrogen production from *** paper reports on a comparative study of using either acetic acid(AA)or trifluoroacetic acid(TFA)as the representative UiO-66 organic modulators for synthesizing visible light responsive UiO-66(Zr)-X(X:NH_(2) or NO_(2))photocatalysts for water *** results show that photocatalytic hydrogen generation from a water/methanol mixture can be improved by varying the nature and amount of the modulator employed to prepare the different UiO-66(Zr)-X(X:NH_(2) or NO_(2))solid ***-66(Zr)-NH_(2) was the most active photocatalyst,followed by UiO-66(Zr)-NO_(2),both prepared with 12 equivalents of AA with respect to the organic *** UiO-66(Zr)-NH_(2) solid was more active than the parent MOF in photocatalytic overall water splitting(OWS)(H_(2) and O_(2) production of 450 and 160μmol·g^(-1),respectively,in 5 h;apparent quantum yield(AQY)at 400 nm of 0.06%)in the absence of methanol and compares favourably with analogous *** on the photocatalytic activity of the most active solids of both series was obtained by means of a series of techniques,including ultraviolet-visible(UV-vis)diffuse reflectance,X-ray photoelectron spectroscopy(XPS),laser flash photolysis(LFP),electron spin resonance(ESR),photoluminescence and photoelectrochemical measurements together with density functional theory(dFT)*** results showed that organic acid modulators can be used to enhance the photocatalytic activity of missing linker UiO-66 defective materials in solar-powered water splitting.

关键词： heterogeneous photocatalysis metal-organic frameworks(MOFs) UiO-66 materials carboxylic acid modulators water splitting solar light

Optimization of Tin-doped Hybrid Perovskite Solar Cells

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Open Journal of Applied Sciences 2024年第3期14卷 687-706页

作者： Bakary Coulibaly Abou Ahou Florentine Kokora desiré Meledje Boko Aka Bernabé Mari Soucase IREN (Institut de Recherche sur les Energies Nouvelles Abidjan Cote d’Ivoire Unité de Formation et de Recherche des Sciences Fondamentales Appliquées (UFRSFA) Universite Nangui Abrogoua Abidjan Cote d’Ivoire Laboratoire de Physiques Fondamentales Appliquées (LPFA) Université Nangui Abrogoua Abidjan Cote d’Ivoire Institut de disseny i Fabricació Universitat Politècnica. València Spain

Perovskites are a category of materials with a unique crystal structure that allows them to absorb sunlight efficiently. This efficiency is particularly high in the case of CH3NH3Pb1-xSnxI3 mixed perovskites. The combination of lead (Pb) and tin (Sn) in this matrix provides a broad spectrum of sunlight absorption, enabling the generation of a larger voltage and, subsequently, increased power. The primary objective in solar cell development is to maximize the conversion of sunlight into electricity. Mixed perovskites like CH3NH3Pb1-xSnxI3 have demonstrated significant potential in this regard. Their tunable bandgap, courtesy of varying the Pb: Sn ratio, allows for the optimization of sunlight absorption. The result is solar cells that surpass many conventional counterparts in terms of energy efficiency. Another significant advantage of these mixed perovskite solar cells is their cost-effectiveness. They can be manufactured using solution-based processes, which are less expensive than the high-vacuum methods required for traditional silicon solar cells. While the prospects for mixed perovskite solar cells are undeniably promising, there are concerns about the toxicity of lead, a key component of these cells. Lead is known to have harmful effects on the environment and health. The aim of our work is to reduce or eliminate lead toxicity in the perovskite cell while maintaining its efficiency. Thus, in a theoretical and experimental approach, we obtained following efficiencies of samples: CH3NH3PbI3 (22.49%) CH3NH3Pb0.75Sn0.25I3 (22.72%), CH3NH3Pb0.5Sn0.5I3 (23.00%) CH3NH3Pb0.25Sn0.75I3 (22.61%), CH3NH3SnI3 (22.38%). doping with 50% tin

关键词： Cost Efficiency Lead/Tin Perovskite Toxicity

A study on wildfire impacts on greenhouse gas emissions and regional air quality in South of Orléans,France

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Journal of Environmental Sciences 2024年第1期135卷 521-533页

作者： Chaoyang Xue Gisèle Krysztofiak Yangang Ren Min Cai Patrick Mercier Frédéric Le Fur Corinne Robin Benoit Grosselin Véronique daele Max RMcGillen Yujing Mu valéry Catoire Abdelwahid Mellouki Laboratoire de Physique et Chimie de l’Environnement et de l’Espace(LPC2E) CNRS–UniversitéOrléans–CNES(UMR 7328)Orléans Cedex 245071France Institut de Combustion AérothermiqueRéactivitéEnvironnement(ICARE)CNRSOrléans Cedex 245071France Research Centre for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Lig’Air-Association de surveillance de la qualitéde l’air en région Centre-val de Loire Saint-Cyr-en-Val 45590France Mohammed V university RabatMorocco

Wildfire events are increasing globally which may be partly associated with climate change,resulting in significant adverse impacts on local,regional air quality and global *** September 2020,a small wildfire(burned area:36.3 ha)event occurred in Souesmes(Loiret-Cher,Sologne,France),and its plume spread out over 200 km on the following day as observed by the MOdIS *** on measurements at a suburban site(~50 km northwest of the fire location)in Orléans and backward trajectory analysis,young wildfire plumes were *** increases in gaseous pollutants(CO,CH_(4),N_(2)O,VOCs,etc.)and particles(including black carbon)were found within the wildfire plumes,leading to a reduced air *** factors,defined as EF(X)=ΔX/ΔCO(where,X represents the target species),of various trace gases and black carbon within the young wildfire plumes were determined accordingly and compared with previous *** in the ambient ions(such as ammonium,sulfate,nitrate,chloride,and nitrite in the particle-and gasphase)and aerosol properties(e.g.,aerosol water content,aerosol p H)were also quantified and ***,we estimated the total carbon and climate-related species(e.g.,CO_(2),CH_(4),N_(2)O,and BC)emissions and compared them with fire emission *** biomass burning emission inventories have uncertainties in estimating small fire burned areas and *** instance,we found that the Global Fire Assimilation System(GFAS)may underestimate emissions(e.g.,CO)of this small wildfire while other inventories(GFEd and FINN)showed significant *** that it is the first time to record wildfire plumes in this region,related atmospheric implications are presented and discussed.

关键词： Wildfire Air quality Emission factor Emission inventory VOLTAIRE supersite

Robust hybrid bismuth perovskites as potential photocatalysts for overall water splitting

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Nano Research 2024年第5期17卷 4593-4601页

作者： Antonio J.Chacón-García Herme G.Baldovi Artem A.Babaryk Antonio Rodríguez-diéguez Sergio Navalón Yolanda Pérez Hermenegildo García Patricia Horcajada Advanced Porous Materials Unit IMDEA Energy InstituteAvda.Ramón y Cajal 328935 MóstolesMadridSpain departamento de Química Universitat Politècnica de València46022 ValènciaSpain departamento Química Inorgánica Universidad de Granada1807GranadaSpain departamento de Biología y Geología Física y Química Inorgánica.ESCET.Universidad Rey Juan Carlos28933 MóstolesMadridSpain Instituto de tecnología química CSIC-UPV Universitat Politècnica de València(UPV)46022Spain

Organic-inorganic hybrid perovskites have gained great attention as promising photocatalysts for hydrogen ***,due to their poor stability in water,the use of aqueous hydrohalic acid solutions is specifically required for an efficient hydrogen ***,three novel photoactive lead-free hybrid perovskites based on bismuth and triazolium cations(denoted as IEF-15,IEF-16,and IEF-17(IEF stands for IMdEA energy frameworks))were synthesized and fully characterized(structural,compositional,optical,etc.).Further,these solids were proposed as photocatalysts for the challenging gas phase overall water splitting(OWS)***,IEF-16 thin films exhibited a remarkable photocatalytic activity in both H_(2) and O_(2) evolution,as a consequence of its appropriate bandgap and energy-band alignment,achieving hydrogen evolution rates ofμmol·g_(H_(2))^(-)1846 and 360 after 24 h under ultraviolet-visible(UV-vis)irradiation or simulated solar irradiation,*** study additionally highlights the remarkable structural and photochemical stability of IEF-16 under different operational conditions(*** volume,irradiation and temperature),paving the way for green hydrogen production from OWS using perovskite-based photocatalysts.

关键词： bismuth-based hybrid perovskites thin films photocatalysis overall water splitting green hydrogen

Chiral forces in longitudinally invariant dielectric photonic waveguides

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Photonics Research 2024年第3期12卷 431-443页

作者： JOSEP MARTÍNEZ-ROMEU IAGO dIEZ SEBASTIAN GOLAT FRANCISCO J.ROdRÍGUEZ-FORTUÑO ALEJANdRO MARTÍNEZ Nanophotonics Technology Center Universitat Politècnica de ValènciaValencia 46022Spain department of Physics King’s College LondonLondon WC2R 2LSUK

We calculate numerically the optical chiral forces in rectangular cross-section dielectric waveguides for potential enantiomer *** study considers force strength and time needed for separating chiral nanoparticles,mainly via quasi-TE guided modes at short wavelengths(405 nm)and the 90°-phase-shifted combination of quasi-TE and quasi-TM modes at longer wavelengths(1310 nm).Particle tracking simulations show successful enantiomer separation within two *** results suggest the feasibility of enantiomeric separation of nanoparticles displaying sufficient chirality using simple silicon photonic integrated circuits,with wavelength selection based on the nanoparticle size.

关键词： dielectric forces quasi

Electrifying Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ) for focalized heating in oxygen transport membranes

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Journal of Energy Chemistry 2024年第4期91卷 99-110页

作者： Marwan Laqdiem Julio García-Fayos Laura Almar Alfonso J.Carrillo Álvaro Represa JoséM.López Nieto Sonia Escolástico david Catalán-Martinez Jose M.Serra Instituto de Tecnología Química(universitat Politècnica de valència–Consejo Superior de Investigaciones Científicas) Av.Los Naranjos s/nE-46022 ValenciaSpain

Industry decarbonization requires the development of highly efficient and flexible technologies relying on renewable energy resources,especially biomass and solar/wind *** the case of pure oxygen production,oxygen transport membranes(OTMs)appear as an alternative technology for the cryogenic distillation of air,the industrially-established process of producing ***,OTMs could provide oxygen from different sources(air,water,CO_(2),etc.),and they are more flexible in adapting to current processes,producing oxygen at 700^(-1)000℃.Furthermore,OTMs can be integrated into catalytic membrane reactors,providing new pathways for different *** first part of this study was focused on electrification on a traditional OTM material(Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ)),imposing different electric currents/voltages along a capillary *** to the emerging Joule effect,the membrane-surface temperature and the associated O_(2) permeation flux could be ***,the OTM is electrically and locally heated and reaches 900℃on the surface,whereas the surrounding of the membrane was maintained at 650℃.The O_(2)permeation flux reached for the electrified membranes was~3.7 NmL min^(-1)cm^(-2),corresponding to the flux obtained with an OTM non-electrified at 900℃.The influence of depositing a porous Ce_(0.8)Tb_(0.2)O_(2-δ) catalytic/protective layer on the outer membrane surface revealed that lower surface temperatures(830℃)were detected at the same imposed electric ***,the electrification concept was demonstrated in a catalytic membrane reactor(CMR)where the oxidative dehydrogenation of ethane(OdHE)was carried *** reaction is very sensitive to temperature,and here,we demonstrate an improvement of the ethylene yield by reaching moderate temperatures in the reaction chamber while the O_(2) injection into the reaction can be easily fine-tuned.

关键词： Oxygen permeation Oxidative dehydrogenation of ethane Oxygen transport membranes Joule effect Mixed ionic-electronic conductors Catalytic membrane reactors

Signaling Mechanisms in Pattern-Triggered Immunity （PTI）

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Molecular Plant 2015年第4期8卷 521-539页

作者： Jean Bigeard Jean Colcombet Heribert Hirt Unite de Recherche en Genomique Vegetale (URGV) UMR INRA/CNRS/Universite d'Evry Val d'Essonne/Saclay Plant Sciences 2 rue Gaston Cremieux 91057 Evry France Center for desert Agriculture 4700 King Abdullah University of Science and Technology (KAUST) Thuwa123955-6900 Kingdom of Saudi Arabia

In nature, plants constantly have to face pathogen attacks. However, plant disease rarely occurs due to efficient immune systems possessed by the host plants. Pathogens are perceived by two different recognition systems that initiate the so-called pattern-triggered immunity （PTI） and effector-triggered immunity （ETI）, both of which are accompanied by a set of induced defenses that usually repel pathogen attacks. Here we discuss the complex network of signaling pathways occurring during PTI, focusing on the involvement of mitogen-activated protein kinases.

关键词： plant defenses plant immunity PTI signaling mechanisms MAPKs