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BaTiO3 solid solutions co-doped with Gd3+ and Eu3+:Synthesis,structural evolution and dielectric properties

Journal of Rare Earths 2024年第10期 1920-1926页

作者： R.Martínez-lópez M.Pérez-labra J.A.Romero-Serrano F.R.Barrientos-Hernández M.Reyes-Pérez M.I.valenzuela-Carrillo G.Urbano-Reyes v.E.Reyes-Cruz G.I.Dávila-Pulido Academic Area of Earth Sciences and Materials Autonomous University of Hidalgo State Metallurgy and Materials Department ESIQIE-IPNUPALM Autonomous University of Coahuila Boulevard Adolfo López Mateos S/n

In this paper,the synthesis,structural evolution,and dielectric properties of BaTiO3solid solutions codoped with rare earth elements(Gd3+and Eu3+) prepared using the solid-state reaction method are *** pure precursor powders of BaCl3,TiO2,Gd2O3,and Eu2O3were mixed in stoichiometric proportions,ground in an agate mortar before being uniaxially pressed at 250 MPa and sintered at 1300℃ in air atmosphere for 6 h to obtain Ba1-3xGd2xTi1-3xEu4xO3（x=0,0.0015,0.01 and0.1）.X-ray diffraction（XRD） and Rietveld's refinement results reveal the crystal phase ferroelectric tetragonal BaTiO3for the samples with x=0,0.0015 and 0.01, as well as a consistent increment in the lattice parameters caused by the *** solubility limit of Gd3+and Eu3+in the BaTiO3structure is reached for the sample with x>0.01,and the orthorhombic Eu2TiO5and monoclinic BaTi2O5secondary phases were *** Raman results show the characteristic peaks of ferroelectric tetragonal BaTiO3around 716 cm-1（lO of A1 symmetry）,515 cm-1（TO of A1 symmetry）,and 305 cm-1（B1）.The maximum relative permittivity measured at 1 kHz was recorded to be 6151.8 for the sample with x=0.0015,and a decrease in the Curie temperature to 105℃ with respect to the undoped sample was *** punctual microanalysis for the samples with x=0.0015,0.01,and 0.1 reveals grains composed of Ba,Ti,O,Gd,and Eu homogeneously distributed in the *** Ba/Ti ratios for samples with x=0.0015,0.01 and 0.1 are 2.86,2.91,and 0.68,respectively,indicating substitution at the Ti site for samples with x=0.0015 and 0.01 and a substitution at the Ba site for the sample with x=0.1.

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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

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Surface Water Processes in Coping with Anthropogenic Impact in a Coastal Eastern Mediterranean Region

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Open Journal of Modern Hydrology 2024年第2期14卷 69-86页

作者： Nour Abboud Zeinab Matar Elias Maatouk véronique Kazpard Research and Analysis Platform for Environmental Sciences (PRASE) Doctoral School of Sciences and Technology (EDST) Lebanese University Hadat Lebanon laboratory of Georessources Geosciences and Environment (L2GE) Faculty of Sciences Lebanese University Fanar Lebanon Department of Earth and life Sciences Faculty of Sciences Lebanese University Hadat Lebanon

Rivers are progressively being exposed to increased anthropogenic pollution stresses that are undermining their designated uses and affecting sensitive coastal areas. In this study, three adjacent eastern Mediterranean coastal rivers, Ibrahim, Kaleb and Beirut, were evaluated. Water quality samples were collected in dry and wet seasons from different sampling sites along the river from the source to the outlet which represent a gradient of increased urbanization. The spatiotemporal variability of the physio-chemical properties, heavy metals (Zn, Pb, Cu, Cr, and Cd) and organic matter (DOC) were statistically analyzed to better understand the contribution of point and nonpoint pollution sources. The three rivers (Beirut, Kaleb and Ibrahim) show a similar behavior in calcium and carbonate alkalinity due to the carbonate mineral weathering effect, so they are of calcium bicarbonate type due to their calcareous geological nature. The speciation of anions was affected by temporal variation. Moreover, it is obvious that the Beirut River has a different behavioral characteristic where the water is a sulfate type water with a preferable metal-OM complexation mainly with lead, zinc and copper, whereas Kaleb and Ibrahim are considered to be of a nitrate phosphate type with a preferable metal inorganic complexation, especially copper, that has a consistent behavior in both types of waters. This difference is attributed to the urbanization effect highly impacting the Beirut River.

关键词： Anions/Cations Metals DOC Complexation Coastal Rivers Spatiotemporal variability

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Enabling Technologies for Autonomous Robotic Systems in Manufacturing

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Transactions of Nanjing University of Aeronautics and Astronautics 2024年第4期41卷 403-431页

作者： ERDŐS Gábor ABAI Kristóf BEREGI Richárd CSEMPESZ János CSERTEG Tamás GODÓGábor HAJÓS Mátyás HÁY Borbála HORvÁTH Dániel HORvÁTH Gergely JUNIKIÁdám KEMÉNY Zsolt KOvÁCS András NACSA János PANITI Imre PEDONE Gianfranco TAKÁCS Emma TIPARY Bence ZAHORÁN lászló vÁNCZA József Institute for Computer Science and Control Hungarian Research Network(HUN-REN SZTAKI)BudapestHungary Department of Manufacturing Science and Technology Budapest University of Technology and Economics(BME)BudapestHungary EPIC Innolabs Nonprofit ltd. BudapestHungary Eötvös loránd University(ElTE) BudapestHungary

Research of autonomous manufacturing systems is motivated both by the new technical possibilities of cyber-physical systems and by the practical needs of the *** operation in semi-structured industrial environments can now be supported by advanced sensor technologies,digital twins,artificial intelligence and novel communication *** enable real-time monitoring of production processes,situation recognition and prediction,automated and adaptive(re)planning,teamwork and performance improvement by *** paper summarizes the main requirements towards autonomous industrial robotics and suggests a generic workflow for realizing such *** case studies will be presented from recent practice at HUN-REN SZTAKI in a broad range of domains such as assembly,welding,grinding,picking and placing,and *** various solutions have in common that they use a generic digital twin concept as their *** making general recommendations for realizing autonomous robotic solutions in the industry,open issues for future research will be discussed.

关键词： industrial robotics autonomy digital twin enabling technology

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STRESS-STRAIN STATE OF ElASTOPlASTIC BODIES WITH CRACK

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Acta Mechanica Solida Sinica 2015年第4期28卷 375-383页

作者： v.v.Glagolev l.v.Glagolev A.A.Markin Tula State University

A physical cut model is used to describe the changes in the stress-strain state （SSS） in elastoplastic bodies weakened by cracks. The distance between the crack edges is considered to be finite in contrast to the mathematical cut. The interactive layer with a thickness limited by the possibility of using the hypothesis of continuity is distinguished on the physical cut extension, Distribution of stresses and strains over the layer thickness is constant and does not depend on the geometry of the boundary between the cut and the interactive layer. The relationship between stresses and strains is determined by the deformation plasticity theory. The problem of plane strain or plane stress state of an arbitrary finite body weakened by a physical cut is reduced to solving a system of two variational equations for displacement fields in the body parts adjacent to the interactive layer. The proposed approach eliminates the singularity in stress distribution in contrast to the mathematical cut model. Use of local strength criteria allows us to determine the time, point and direction of the fracture initiation. Possibilities of the proposed model are illustrated by solving the problems of determining the SSS of a rectangular body weakened by a physical cut under symmetric and antisymmetric loadings.

关键词： crack physical cut characteristic size elastoplastic deformations

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Electro-Optical Model of Soiling Effects on Photovoltaic Panels and Performance Implications

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Energy Engineering 2024年第2期121卷 243-258页

作者： A.Asbayou G.P.Smestad I.Ismail A.Soussi A.Elfanaoui l.Bouhouch A.Ihlal laboratory of Materials and Renewable Energies University Ibn ZohrAgadir80000Morocco Sol Ideas Technology Development San José95150USA

In this paper,a detailed model of a photovoltaic(Pv)panel is used to study the accumulation of dust on solar *** presence of dust diminishes the incident light intensity penetrating the panel’s cover glass,as it increases the reflection of light by *** phenomenon,commonly known as the“soiling effect”,presents a significant challenge to Pv systems on a global *** basic models of the equivalent circuits of a solar cell can be found,namely the single-diode model and the two-diode *** limitation of efficiency data in manufacturers’datasheets has encouraged us to develop an equivalent electrical model that is efficient under dust conditions,integrated with optical transmittance considerations to investigate the soiling *** proposed approach is based on the use of experimental current-voltage(I-v)characteristics with simulated data using MATlAB/*** research outcomes underscores the feasibility of accurately quantifying the reduction in energy production resulting from soiling by assessing the optical transmittance of accumulated dust on the surface of Pv glass.

关键词： Photovoltaics solar energy optical transmittance soiling dust Pv performance

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Influence of Turbulence Intensity and Turbulence length Scale on the Drag, lift and Heat Transfer of A Circular Cylinder

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China Ocean Engineering 2017年第3期31卷 357-363页

作者： I.v. Morenko v.l. Fedyaev Institute of Mechanics and Engineering Kazan Science Center Russian Academy of Sciences (IME KazSC RAS) Kazan Russian Federation Kazan National Research Technical University named after A.N. Tupolev - KAI (KNRTU-KAI) Kazan Russian Federation

Influence of the turbulence intensity and turbulence length scale on the hydrodynamic characteristics and heat transfer of a circular cylinder, streamlined by a viscous fluid flow, is numerically studied. We take the Reynolds number of the oncoming flow equal to 4×10^4, the turbulence intensity Tuf and the dimensionless turbulence length scale l-f varying from 1.0% to 40% and from 0.25 to 4.0, respectively. We confirmed that the increase of Tuf leads to the suppression of the periodic vortex shedding from the cylinder surface, and as a result the stationary mode of streamlining is formed. Consequently, with the increasing turbulence intensity directly in front of the cylinder Tu＊, the amplitude of the lift coefficient decreases monotonically. Nevertheless, the time-averaged drag coefficient of the streamlined cylinder decreases at Tu＊〈6.0%, and increases at Tu＊〉9.0%. The dependence of the average Nusselt number on Tu＊ is near-linear, and with the increasing turbulence intensity, the Nusselt number rises. However, the change of the average Nusselt number depending on l-f is non-monotonic and at lf=l.0, the value reaches its maximum

关键词： hydrodynamics turbulence heat transfer of a circular cylinder

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Effect of biochar on the metabolome of soybean seedlings

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Oil Crop Science 2024年第1期9卷 60-68页

作者： Nathalia E.Silva Mariana G.Aguilar Osania E.Ferreira Gleicia M.Paulino Jaqueline C.l.Carvalho lúcia P.S.Pimenta Alan R.T.Machado Programa de Pos-graduaçao em Ciencias Ambientais Universidade do Estado de Minas GeraisFrutalMinas Gerais38202-436Brazil Departamento de Química Universidade Federal de Minas GeraisMinas GeraisBelo Horizonte31270-901Brazil Departamento de Engenharia Aplicada e Tecnologias Ambientais Universidade do Estado de Minas GeraisJoao MonlevadeMinas Gerais35930-314Brazil Departamento de Ciencias Exatas Universidade do Estado de Minas GeraisJoao MonlevadeMinas Gerais35930-314Brazil

The use of biochar can have several effects on plant germination,depending on raw material,preparation method and application ***,the molecular mechanisms that lead to those results have yet to be *** aim of this research was to improve the understanding of these mechanisms by characterizing the metabolic effects of sugarcane bagasse biochar on soybean *** types of biochars were prepared by pyrolysis at 300℃(SCB300),400℃(SCB400)and 600℃(SCB600).Then,each one was mixed into sand at 1%,3%,5%(w/w)dose,*** experiment was performed in 8 days of incubation,when the number of germinated seeds and the average radicle length were *** evaluate the metabolome,the dry biomass(DB)was subjected to extraction with a mixture of methanol-d4 and D2O(1:1 v/v).The extracts were submitted to metabolomics analysis by Proton Nuclear Magnetic *** Relative Germination,Relative Average Radicle Growth and Germination Index increased in all treatments compared to *** the other hand,the DB increased in all treatments,except for SCB300,at doses of 1%and 3%w/*** metabolites(alanine,asparagine,acetic acid,citric acid,glycerol,fatty acids and sucrose)were identified and quantified in DB extracts as the most influential finding for the separation of *** together,these results strongly suggested that biochars accelerated the catabolism of triacylglycerols to sucrose and induced a slight osmotic stress.

关键词： Germination Metabolomics 1H NMR Pyrolysis Sugarcane bagasse

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Food safety management and regulation:International experiences and lessons for China

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Journal of Integrative Agriculture 2015年第11期14卷 2218-2230页

作者： l Unnevehr v Hoffmann Agricultural and Consumer Economics University of Illinois Urbana-Champaign International Food Policy Research Institute

China is experiencing rapid urbanization, changes in diets, and modernization of food retailing and production. In this context, food safety can become a greater concern for a variety of reasons. The purpose of this article is to review the international experiences and lessons regarding food safety management, regulation, and consumer behavior, with the goal of identifying how to improve food safety in middle income countries such as China. International experience in addressing food safety provides two general kinds of lessons. First, a middle-income country such as China needs to develop the capacity to carry out risk analysis in order to better focus public resources on the most important risks. Second, it will be important to leverage market incentives so as to make the best use of limited public capacity to enforce standards. Inter- national experiences show that food safety management is feasible where market incentives exist, and that public-private partnerships can support the process of improving food safety management. Market incentives require effective consumer or buyer demand, mechanisms to identify and reward quality, and supply chain coordination. Public efforts can be targeted to supporting these market developments for the risks that are the greatest burden to public health.

关键词： food safety regulation supply chain coordination risk analysis

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Exclusive γ^(*)γ processes

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Chinese Physics C 2010年第6期34卷 822-830页

作者： v.l.Chernyak Budker Institute of Nuclear Physics

A short review of experimental and theoretical results on the large angle cross sections ＂γγ→ twomesons＂ and the form factors γ＊γ→ P = {π, η, η＇} is given.

关键词： mesons two photon processes form factor

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