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BaTiO_(3)solid solutions co-doped with Gd^(3+)and eu^(3+):Synthesis,structural evolution and dielectric properties

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journal of Rare earths 2024年第10期42卷 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 StateRoad Pachuca-Tulancingo Km 4.5 Mineral de La Reforma.Hidalgo42184Mexico Metallurgy and Materials Department ESIQIE-IPNUPALMZacatencoCiudad de Mexico07738Mexico Autonomous University of Coahuila Boulevard Adolfo López Mateos S/nNueva RositaCoahuila26800Mexico

In this paper,the synthesis,structural evolution,and dielectric properties of BaTiO_(3)solid solutions codoped with rare earth elements(Gd^(3+)and eu^(3+))prepared using the solid-state reaction method are *** pure precursor powders of BaCl_3,TiO_(2),Gd_(2)O_(3),and eu_(2)O_(3)were 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 Ba_(1-3x)Gd_(2x)Ti_(1-3x)eu_(4x)O_(3)(x=0,0.0015,0.01 and0.1).X-ray diffraction(XRD)and Rietveld's refinement results reveal the crystal phase ferroelectric tetragonal BaTiO_(3)for 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 Gd^(3+)and eu^(3+)in the BaTiO_(3)structure is reached for the sample with x>0.01,and the orthorhombic eu_2TiO_(5)and monoclinic BaTi_(2)O_(5)secondary phases were *** Raman results show the characteristic peaks of ferroelectric tetragonal BaTiO_(3)around 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 BaTiO_(3)*** 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.

关键词： BaTiO_(3) Doping Gadolinium europium Synthesis Rare earths

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efficiency and effectiveness of systems for the treatment of domestic wastewater based on subsurface flow constructed wetlands in jarabacoa, Dominican Republic

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Water Science and engineering 2024年第2期17卷 118-128页

作者： Yvelisse pérez enmanuel Vargas Daniel Garcia-Cortes William Hernandez Humberto Checo Ulises jauregui-Haza Area de Ciencias Basicas y Ambientales Instituto Tecnologico de Santo Domingo(INTEC)Avenida de Los Proceres 49Los Jardines del NorteSanto Domingo 10602Dominican Republic Ministry of environment and Natural Resources Calle Cayetano Germosen esq.Ave.LuperonEl PedregalSanto Domingo 11107Dominican Republic plan Yaque Calle Estela Geraldino 14 AltosJarabacoa 41000Dominican Republic Institute of Technologies and Applied Sciences University of HavanaHavana 10400Cuba

Constructed wetlands(CwW)are well known nature-based systems for water *** study evaluated the efficiency and effectiveness of seven domestic wastewater treatment systems based on horizontal flow CWs in jarabacoa,the Dominican *** results showed that the CWs were efficient in reducing the degree of contamination of wastewater to levels below the Dominican wastewater discharge standards for parameters such as the 5-day biochemical oxygen demand(BOD5)and chemical oxygen demand,but not for the removal of phosphorus and fecal *** addition,a horizontal flow subsurface wetland in the peri-urban area el Dorado was evaluated in terms of the performance of wastewater treatment in tropical climatic *** concentrations of heavy metals,such as zinc,copper,chromium,and iron,were found to decrease in the effluent of the wetland,and the concentrations for nickel and manganese tended to *** levels of heavy metals in the effluent were lower than the limit values of the Dominican wastewater discharge *** construction cost of these facilities was around 200 USD per population equivalent,similar to the cost in other countries in the same *** study suggested some solutions to the improved performance of CWs:selection of a microbial flora that guarantees the reduction of nitrates and nitrites to molecular nitrogen,use of endemic plants that bioaccumulate heavy metals,combination of constructed wetlands with filtration on activated carbon,and inclusion of water purification processes that allow to evaluate the reuse of treated water.

关键词： Domestic wastewater Constructed wetland BOD COD pathogens Heavy metals

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

Are hydrides under high-pressure-high-temperature superconductors?

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National Science Review 2024年第7期11卷 9-12页

作者： j.e.Hirsch Department of physics University of California

Contrary to the current consensus, I argue that the existing evidence for high-temperature superconductivity in hydrides under high pressure is not compelling. I suggest that the focus of the field should urgently shift to establish unequivocally experimentally whether or not superconductivity in pressurized hydrides exists, instead of continuing to search for new materials that might show elusive signals of unproven superconductivity at ever higher temperatures. The implications of a negative finding for the theoretical understanding of superconductivity are discussed.

关键词： Hydrides

Unmixing detrital zircon U-pb ages reveals tectonic and climatic depositional influences on the Carboniferous Ansilta Formation,Calingasta-Uspallata Basin,Western Argentina

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Geoscience Frontiers 2024年第4期15卷 61-77页

作者： j.R.Malone j.e.Malone j.L.Isbell D.H.Malone j.p.Craddock K.N.pauls Department of Geological Sciences Jackson School of GeosciencesUniversity of Texas at AustinAustinTX 78712USA Iowa Geological Survey University of IowaIowa CityIA 52240USA Department of Geosciences University of Wisconsin-MilwaukeeMilwaukeeWI 53211USA Department of Geography Geology and the EnvironmentIllinois State UniversityNormalIL 61790-4400USA

The Late paleozoic Ice Age(LpIA)was a principal control of sedimentation across Gondwana from the late Devonian through early *** assess the hypothesis that glacial to interglacial transitions in western Argentina were the primary control influencing sediment routing patterns among the various Carboniferous-permian basins in western *** Carboniferous Ansilta Formation consists of glaciomarine,nearshore,and fluvial systems deposited during the LpIA along the eastern margin of the Calingasta-Uspallata Basin in *** lower,glacially influenced succession of the Ansilta Formation records at least five glacial advances;the upper succession of consists of progradational shallow marine,deltaic,and fluvial *** combine 1225 new U-pb zircon ages from six samples of the Carboniferous Ansilta Formation in the Calingasta-Uspallata Basin with 5864 U-pb ages from 147 pub-lished samples in the detrital pymix forward mixture model to characterize provenance *** the glacially influenced lower Ansilta Formation,sediment was derived locally from the protoprecordillera,which was a prominent highland with alpine glaciers flowing west and east into the Calingasta-Uspallata and paganzo basins,***,there was little or no connection between these two basins during Serpukhovian-Bashkirian *** fluvial/deltaic upper Ansilta had distal sediment sources in the Sierras ***,our results support the collapse of the protoprecordillera topographic barrier,enabling drainage patterns connecting the paganzo and Calingasta-Uspallata basins by late pennsylvanian-early permian time.

关键词： Late paleozoic Ice Age Argentina Calingasta-Uspallata Basin Ansilta Formation Detrital zircon provenance

exploring the effects of anthropogenic disturbance on predator inspection activity in Trinidadian guppies

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Current Zoology 2024年第1期70卷 109-111页

作者： Alix j.p Brusseau Laurence e.A.Feyten Adam L.Crane Grant e.Brown Department of Biology Concordia UniversityMontrealQCH4B 1R6Canada Department of Biomedical Sciences WCVMUniversity of SaskatchewanSaskatoonSKCanada

prey animals are often faced with uncertainty due to having imperfect information regarding current local conditions,including predation risks and the availability of reliable foraging opportunities(Dall 2010).As this uncertainty increases,the probability of making costly behavioral errors also increases,leading to more risk averse behavioral tactics(Feyten et al.2019).For example,Trinidadian guppies poecilia reticulata are far more risk averse when faced with multiple unknown sources of risk assessment information than when faced with a mix of known and unknown cues(Feyten et al.2019).prey can reduce uncertainty by gathering and integrating private and social information regarding current risk levels within microhabitats(Dall 2010;Munoz and Blumstein 2012).

关键词： human disturbance information availability information reliability predator-prey interactions risk assessment uncertainty

Single atom Cu-N-C catalysts for the electro-reduction of CO_(2) to CO assessed by rotating ring-disc electrode

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journal of energy Chemistry 2024年第1期88卷 169-182,I0004页

作者： S.pérez-Rodríguez M.Gutiérrez-Roa C.Giménez-Rubio D.Ríos-Ruiz p.Arévalo-Cid M.V.Martínez-Huerta A.Zitolo M.j.Lázaro D.Sebastián Instituto de Carboquímica(CSIC) Miguel Luesma Castán 450018 ZaragozaSpain Instituto de Catálisis y petroleoquímica(CSIC) Marie Curie 228049 MadridSpain Synchrotron SOLeIL L’Orme des MerisiersDépartementale 12891190France

The electrochemical CO_(2) reduction reaction(CO_(2)RR) to controllable chemicals is considered as a promising pathway to store intermittent renewable energy. Herein, a set of catalysts based on copper-nitrogendoped carbon xerogel(Cu-N-C) are successfully developed varying the copper amount and the nature of the copper precursor, for the efficient CO_(2)RR. The electrocatalytic performance of Cu-N-C materials is assessed by a rotating ring-disc electrode(RRDe), technique still rarely explored for CO_(2)RR. For comparison, products are also characterized by online gas chromatography in a H-cell. The as-synthesized Cu-NC catalysts are found to be active and highly CO selective at low overpotentials(from -0.6 to -0.8 V ***) in 0.1 M KHCO_(3), while H_(2) from the competitive water reduction appears at larger overpotentials(-0.9 V vs. RHe). The optimum copper acetate-derived catalyst containing Cu-N_(4) moieties exhibits a CO_(2)-to-CO turnover frequency of 997 h^(-1) at -0.9 V vs. RHe with a H_(2)/CO ratio of 1.8. These results demonstrate that RRDe configuration can be used as a feasible approach for identifying electrolysis products from CO_(2)RR.

关键词： Cu-N-C Carbon xerogel Rotating ring disc electrode Carbon dioxide reduction reaction Carbon monoxide

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Selection of digital fabrication technique in the construction industry--A multi-criteria decision-making approach

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Frontiers of Structural and Civil engineering 2024年第7期18卷 977-997页

作者： M.p.SALAIMANIMAGUDAM j.jAYApRAKASH Department of Structural and Geotechnical engineering School of Civil EngineeringVellore Institute of TechnologyVellore 632014India

Digital fabrication techniques,in recent decades,have provided the basis of a sustainable revolution in the construction ***,selecting the digital fabrication method in terms of manufacturability and functionality requirements is a complex *** paper presents alternatives and criteria for selection of digital fabrication techniques by adopting the multi-criteria decision-making *** alternatives considered in the study are concrete three-dimensional(3D)printing,shotcrete,smart dynamic casting,material intrusion,mesh molding,injection concrete 3D printing,and thin forming *** criteria include formwork utilization,reinforcement incorporation,geometrical complexity,material enhancement,assembly complexity,surface finish,and build *** demonstrates different multi-criteria decision-making techniques,with both subjective and objective weighting *** given ranking is based on the current condition of digital fabrication in the construction *** study reveals that in the selection of digital fabrication techniques,the criteria including reinforcement incorporation,build area,and geometrical complexity play a pivotal role,collectively accounting for nearly 70% of the overall *** the evaluated techniques,concrete 3D printing emerged as the best performer,however the shotcrete and mesh molding techniques in the second and third positions.

关键词： digital fabrication multicriteria decision-making concrete 3D printing

Reuse of port industrial heritage in tourist cities:Shipyards as case studies

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Frontiers of Architectural Research 2024年第1期13卷 164-183页

作者： María j.Andrade eduardo jiménez-Morales Rachel Rodríguez-Ramos pablo Martínez-Ramírez Department of Art and Architecture School of ArchitectureMalaga UniversityMalaga 29013Spain

The progressive deindustrialisation of many western cities since the 1980s has led to many industrial zones linked to port activities being abandoned or falling into *** such as Barcelona,Naples,Lisbon,Amsterdam,and Hamburg have port industrial complexes of high tangible and intangible heritage value that could totally or partially disappear,resulting in an irreparable loss of their scientific,architectural,social,technological,and historical *** that in mind,Adaptive Reuse(AR)of the built heritage allows the industrial memory of the ports to be preserved by turning them into new functional centres within the existing urban *** occurs in the context of the contemporary challenges of those cities,such as touristification,the circular economy and climate change,while guaranteeing the life cycle of those *** article analyses two case studies—the Nederlandsche Scheepsbouw Maatschappij(NDSM)and the Rotterdamsche Droogdok Maatschappij(RDM)shipyards,both in the Netherlands—in order to contribute to the knowledge of AR of port Industrial *** are two examples of good practices in port industrial heritage interventions,where the factors behind their acclaim can be easily highlighted.A multi-scale methodology is therefore used and tailored to the case of port industrial heritage,based on analysing previous studies of the heritage in different spheres and on different scales.A relationship matrix tool is thus *** enables a comparative study to be conducted,using key variables and indicators,and considering qualitative and quantitative *** provides extensive output information for each case study,which is summarised in the most favourable factors for the success of the AR of this port industrial heritage.

关键词： Industrial heritage port-city Adaptive reuse Best practices Circular economy HUL Touristification

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