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frontiers of Chemical Science and Engineering 2021年第2期15卷 399-409,F0004页

作者： fernando f.rivera Berenice Miranda-Alcantara German Orozco Carlos Ponce de Leon Luis f.Arenas National Council of Science and Technology(CONACYT) Mexico City 03940Mexico Center of Research and Technological Development in Electrochemistry(CIDETEQ) Queretaro 76703Mexico Electrochemical Engineering Laboratory Energy Technology Research GroupFaculty of Engineering and Physical SciencesUniversity of SouthamptonSouthampton SO171BJUK

Description of electrolyte fluid dynamics in the electrode compartments by mathematical models can be a powerful tool in the development of redox flow batteries(RfBs)and other electrochemical *** order to determine their predictive capability,turbulent Reynolds-averaged Navier-Stokes(RANS)and free flow plus porous media(Brinkman)models were applied to compute local fluid velocities taking place in a rectangular channel electrochemical flow cell used as the positive half-cell of a cerium-based RfB for laboratory *** different platinized titanium electrodes were considered,a plate plus a turbulence promoter and an expanded metal *** pressure drop was validated against experimental data obtained with typical cerium *** was found that the pressure drop values were better described by the RANS approach,whereas the validity of Brinkman equations was strongly dependent on porosity and permeability values of the porous media.

关键词： CfD simulation porous media porous electrode pressure drop redox flow battery

Stochastic seismic inversion and Bayesian facies classification applied to porosity modeling and igneous rock identification

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Petroleum Science 2024年第2期21卷 918-935页

作者： fábio Júnior Damasceno fernandes Leonardo Teixeira Antonio fernando Menezes freire Wagner Moreira Lupinacci Exploratory Interpretation and Reservoir Characterization Group(GIECAR) Department of Geology and GeophysicsFederal Fluminense UniversityNiter oiRJ24210-346Brazil Petrobras Rio de JaneiroRJ20231-030Brazil National Institute of Science and Technology of Petroleum Geophysics(INCT-GP/CNPQ) Niter oiRJ24210-346Brazil

We apply stochastic seismic inversion and Bayesian facies classification for porosity modeling and igneous rock identification in the presalt interval of the Santos Basin. This integration of seismic and well-derived information enhances reservoir characterization. Stochastic inversion and Bayesian classification are powerful tools because they permit addressing the uncertainties in the model. We used the ES-MDA algorithm to achieve the realizations equivalent to the percentiles P10, P50, and P90 of acoustic impedance, a novel method for acoustic inversion in presalt. The facies were divided into five: reservoir 1,reservoir 2, tight carbonates, clayey rocks, and igneous rocks. To deal with the overlaps in acoustic impedance values of facies, we included geological information using a priori probability, indicating that structural highs are reservoir-dominated. To illustrate our approach, we conducted porosity modeling using facies-related rock-physics models for rock-physics inversion in an area with a well drilled in a coquina bank and evaluated the thickness and extension of an igneous intrusion near the carbonate-salt interface. The modeled porosity and the classified seismic facies are in good agreement with the ones observed in the wells. Notably, the coquinas bank presents an improvement in the porosity towards the top. The a priori probability model was crucial for limiting the clayey rocks to the structural lows. In Well B, the hit rate of the igneous rock in the three scenarios is higher than 60%, showing an excellent thickness-prediction capability.

关键词： Stochastic inversion Bayesian classification Porosity modeling Carbonate reservoirs Igneous rocks

Thermoluminescence characterization of natural and synthetic irradiated Ce-monazites

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Journal of Rare Earths 2024年第4期42卷 643-650页

作者： V.Correcher C.Boronat J.Garcia-Guinea J.f.Benavente T.rivera-Montalvo CIEMAT Av.Complutense 4028040MadridSpain MNCN-CSIC J.Gutierrez Abascal 228006MadridSpain Instituto Politécnico Nacional CICATA-IPNAv.Legaria 694Mexico City11500Mexico

The thermoluminescence(TL)emission of synthetic and natural Ce-monazites was characterized here to determine the potential application in the identification of microscopic defects from a qualitative point of view trying to link each TL peak to a chemical-physical *** kinetic parameters that lead the luminescence processes were calculated by means of variable heating rate and computing glow curve deconvolution methods and allow identifying three groups of components at~90,130 and 290℃(for the mineral sample)and~90,170,220,270 and 320℃(for the synthetic CePO_(4):Nd_(0.20),La_(0.25)).The main differences appreciated in these complex TL curves are mainly due to(i)the content of impurities(natural sample contains lanthanides as well as U 0.60%and Th 5.22%)and(ii)the degree of crystallinity of the samples which is directly related to the type of impurities(synthetic monazite relies only on Nd and La).The behavior of the dose response in the range of 1-8 Gy is similar for both samples;the TL intensity increases linearly as the dose increases without changes in the position of the maxima,denoting first-order kinetic luminescence *** peak could be mostly associated with structural defects(i.e.,phase transitions),chemical reactions(i.e.,Ce3+?Ce4+redox reaction,dehydration or dehydroxylation processes)or intrinsic defects(i.e.,frenkel defects,ODCs or NBOHCs).

关键词： Thermoluminescence Kineticparameters Phosphate Ce-monazite Defects Rare earths

Time-Series Embeddings from Language Models:A Tool for Wind Direction Nowcasting

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Journal of Meteorological Research 2024年第3期38卷 558-569页

作者： Decio ALVES fabio MENDONCA Sheikh Shanawaz MOSTAfA fernando MORGADO-DIAS University of Madeira Campus Universitário da Penteada9020-105FunchalPortugal Interactive Technologies Institute/Laboratory for Robotics and Engineering Systems and Agência Regional para o Desenvolvimento da Investigação Tecnologia e InovaçãoEdif.Madeira TecnopoloCaminho da Penteada piso-29020-105FunchalPortugal

Wind direction nowcasting is crucial in various sectors,particularly for ensuring aviation operations and *** this context,the TELMo(Time-series Embeddings from Language Models)model,a sophisticated deep learning architecture,has been introduced in this work for enhanced wind-direction *** by using three years of data from multiple stations in the complex terrain of an international airport,TELMo incorporates the horizontal u(east-west)and v(north-south)wind components to significantly reduce forecasting *** a day with high wind direction variability,TELMo achieved mean absolute error values of 5.66 for 2-min,10.59 for 10-min,and 14.79 for 20-min forecasts,processed within a swift 9-ms/step *** degree-based analysis,in comparison,yielded lower performance,emphasizing the effectiveness of the u and v *** contrast,a Vanilla neural network,representing a shallow-learning approach,underperformed in all analyses,highlighting the superiority of deep learning methodologies in wind direction *** is an efficient model,capable of accurately forecasting wind direction for air traffic operations,with an error less than 20°in 97.49%of the predictions,aligning with recommended international *** model design enables its applicability across various geographical locations,making it a versatile tool in global aviation meteorology.

关键词： wind nowcasting wind components wind direction time series prediction deep learning

feeding ecology and interactions with mammal hosts in a symbiotic genus of birds(Buphagus spp.)in Namibia

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Avian Research 2024年第3期15卷 336-344页

作者： Michael S.Lukubwe Daniel Velarde-Garcéz fernando Sequeira Susana Lopes Adrian J.f.K.Craig Vanessa A.Mata Department of Zoology and Entomology Rhodes UniversityMakhandaSouth Africa Department of Wildlife Management and Tourism Studies University of NamibiaKatima Mulilo CampusNamibia Departamento de Biologia Faculdade de CiênciasUniversidade do PortoPortoPortugal CIBIO Centro de Investigação em Biodiversidade e Recursos GenéticosInBIO Laboratório AssociadoCampus de VairãoVairãoPortugal BIOPOLIS Program in Genomics Biodiversity and Land PlanningCIBIOCampus de VairãoVairãoPortugal

As the sole obligate symbiotic birds in Africa,oxpeckers offer a unique model for studying symbiotic *** to the multitrophic level they occupy and the context dependent foraging behavior they exhibit,the type of symbiotic relationship can be *** addition to providing a cleaning service to the host by removing ticks,oxpeckers frequently feed on blood,mucus,and saliva,inflicting potential damage on the ***,we used DNA metabarcoding on faecal samples to analyze the taxonomic composition of the trophic interactions of the Yellow-billed Oxpecker(Buphagus africanus)and Red-billed Oxpecker(***)in northeastern *** contrast to conventional methods,DNA metabarcoding allows for a detailed identification of dietary resources encompassing both mammal hosts and consumed arthropods within the same *** this information,we examined differences in the diet composition between oxpecker species and localities,as well as the co-occurrence between host and arthropod *** findings revealed that oxpeckers predominantly source their diet from mammals,ticks,and flies;however,ticks and flies rarely co-occur in the diet of an *** observed variability among individuals in their feeding ecology,which is strongly correlated with locality and,to a lesser extent,with the mammal *** noted a high degree of mobility between hosts within relatively short periods,with 32%of the samples showing traces of at least two mammal *** study illustrates the dynamic foraging behavior of these specialized symbiotic birds,shedding light on their potential role in pest control services and disease transmission.

关键词： Commensalism Diet DNA metabarcoding Oxpeckers Parasitism Trophic ecology

Predicting grain size-dependent superplastic properties in friction stir processed ZK30 magnesium alloy with machine learning methods

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Journal of Magnesium and Alloys 2024年第5期12卷 1931-1943页

作者： farid Bahari-Sambran fernando Carreno C.M.Cepeda-Jiménez Alberto Orozco-Caballero Physical Metallurgy Department CENIM-CSICAv.Gregorio del Amo 828040 MadridSpain Department of Mechanical Engineering Chemistry and Industrial DesignPolytechnic University of MadridRonda de Valencia 328012MadridSpain

The aim of this work is to predict,for the first time,the high temperature flow stress dependency with the grain size and the underlaid deformation mechanism using two machine learning models,random forest(Rf)and artificial neural network(ANN).With that purpose,a ZK30 magnesium alloy was friction stir processed(fSP)using three different severe conditions to obtain fine grain microstructures(with average grain sizes between 2 and 3μm)prone to extensive superplastic *** three friction stir processed samples clearly deformed by grain boundary sliding(GBS)deformation mechanism at high *** maximum elongations to failure,well over 400% at high strain rate of 10^(-2)s^(-1),were reached at 400℃ in the material with coarsest grain size of 2.8μm,and at 300℃ for the finest grain size of 2μ***,the superplastic response decreased at 350℃ and 400℃ due to thermal instabilities and grain coarsening,which makes it difficult to assess the operative deformation mechanism at such *** work highlights that the machine learning models considered,especially the ANN model with higher accuracy in predicting flow stress values,allow determining adequately the superplastic creep behavior including other possible grain size scenarios.

关键词： Machine learning Artificial intelligence Magnesium alloys Superplasticity friction stir processing Grain coarsening

Erbium photoluminescence response related to nanoscale heterogeneities in sol-gel silicates

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Journal of Rare Earths 2013年第1期31卷 18-26页

作者： H.C.Vasconcelos M.G.Meirelles f.rivera-López Department of Technological Sciences and Development Azores University CEfITEC-Centre of Physics and Technological Research Physics Department of FCT/UNL Department of fundamental and Experimental Physics Electronics and SystemsUniversity of La Laguna

Sol-gel glassy films of the SiO2-TiO2-PO2.5-ErO2.5 system containing nanocrystallites of ErPO4, were obtained through suitable heat treatments. Variations in the shape and intensity of the Er3＋ photoluminescent signal around 1500 nm were linked to the nature of the host environment of the active ions; the specific features of the photoluminescent emission spectrum of the erbium 4113/2 metastable level were interpreted in terms of structural changes in the glassy films. The photoluminescent spectrum was found to be sensitive to the order （crystalline） or disorder （amorphous） of the Er3＋ ions neighbour within the glassy matrix. An amorphous envi- ronment led to a broadening of Er3＋ PL emission band while a crystalline one was responsible for a drastic photoluminescent band- width narrowing. The presence of nanoscale heterogeneities caused a drastic photoluminescence intensity decrease. Changes in the shape of the decay curve of fluorescence lifetime were found also structurally dependent on volumetric defects, occurrence of phase separation and Er3＋-Er3＋ clustering effects as well.

关键词： sol-gel Er3+ optical probe nanoscale heterogeneities photoluminescence ErPO4 rare earths

Deciphering the fiber quality of Gossypium barbadense *** in La Convención,Cusco,Perú

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Journal of Cotton Research 2024年第3期7卷 231-242页

作者： MORALES-ARANIBAR Luis SAENZ Manuel Canto MORALES-ARANIBAR Carlos Genaro rivera Marite Yulisa Nieves AGUILERA Jorge González STEINER fábio BARDIVIESSO Diógenes Martins ZUffO Alan Mario National Intercultural University of Quillabamba Cusco 08741Peru Universidad Nacional Agraria La Molina(UNALM) Lima 012Peru Graduate School Jorge Basadre Grohmann National UniversityTacna 583000Peru National Institute of Agrarian Innovation(INIA) Lima 15024Peru Department of Agronomy State University of Mato Grosso do Sul(UEMS)Cassilândia 79540‑000MSBrazil Department of Agronomy State University of Maranhão(UEMA)Balsas 65800‑000MABrazil

Background The quality of cotton fiber determines its value in the textile market,influencing agricultural profitability and the efficiency of textile *** selection of genotypes with superior fibers is a key factor for genetic improvement programs seeking adaptability and sustainability in the face of climate *** demonstrates the strategic importance of this plant for sustainable agriculture and the global textile *** objective of this research was to decipher the fiber quality of Gossypium barbadense *** in the native Amazonian communities of La Convención,Cusco-Perú,and to evaluate other critical aspects of native cotton that have not yet been *** methodology included non-probability sampling for accessibility,qualitative and quantitative analyses,and multivariate *** fiber length(mm),micronaire index(maturity/fineness),fiber strength(gf/tex),length uniformity index(%),fiber elongation(%),maturation index(%),and short fiber index(%)were the fiber characteristics evaluated using the HVI method in cotton *** Cotton accessions collected from Koribeni(Gossypium spp.)and Shivankoreni(Gossypium barbadense ***)stood out for their fiber quality properties,especially length,strength,and uniformity,which highlights their relevance for advanced textile applications and potential for use in plant genetic improvement *** These findings reinforce the need to conserve and study these native cotton accessions from the Peruvian Amazon region,which can offer promising perspectives for the textile industry and agricultural biodiversity.

关键词： Cotton Sustainability Amazonian communities Cotton fiber quality

Rotating effects on the photoionization cross-section of a 2D quantum ring

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Communications in Theoretical Physics 2024年第10期76卷 153-159页

作者： Carlos Magno O Pereira frankbelson dos S Azevedo Luís fernando C Pereira Edilberto O Silva Departamento de física Universidade Federal do Maranh?o

In this article, we investigate the nonrelativistic quantum motion of a charged particle within a rotating frame, taking into account the Aharonov–Bohm(AB) effect and a uniform magnetic field. Our analysis entails the derivation of the equation of motion and the corresponding radial equation to describe the system. Solving the resulting radial equation enables us to determine the eigenvalues and eigenfunctions, providing a clear expression for the energy levels. furthermore,our numerical analysis highlights the substantial influence of rotation on both energy levels and optical properties. Specifically, we evaluate the photoionization cross-section with and without the effects of rotation. To elucidate the impact of rotation on the photoionization process of the system, we present graphics that offer an appealing visualization of the intrinsic nature of the physics involved.

关键词： Aharonov-Bohm effect photoionization cross-section quantum ring rotating effect

Morphometry and Mineral Content in the Seeds and Soil of Two Species of Argemone L.(Papaveraceae)in the Central Part of the Chihuahuan Desert

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Phyton-International Journal of Experimental Botany 2024年第2期93卷 371-386页

作者： Perla Patricia Ochoa-García Jaime Sánchez-Salas Ricardo Trejo-Calzada Jesús JosafathQuezada-rivera fabián García-González Unidad Regional Universitaria de ZonasÁridas BermejilloUniversidad Autónoma ChapingoDurango35230México facultad de Ciencias Biológicas Universidad Juárez del Estado de DurangoGómez PalacioDurango35010México

The genus Argemone L.(Papaveraceae)is found widely distributed in Mexico’s Chihuahuan Desert(CD).Some species of this genus are of phytochemical or ethnobotanical *** are inedible plants considered as *** date they have not been broadly studied;thus,their ecology is,to our knowledge,*** present work was centered around carrying out a morphometric analysis and the determination of minerals in the soil and seeds of the wild populations of Argemone at sites belonging to two ecoregions of the CD in *** April 2021 and April 2022,seeds of Argemone spp.,and soil samples were collected at 10 sites of the *** seeds were selected under a randomized design,and weight,length,diameter,thickness,buoyancy,and mineral content were *** soil samples were obtained under the Mexican regulation NOM-021-RECNAT-2000,and determinations of mineral content,electrical conductivity,apparent density,and soluble anions were *** information obtained was grouped by variable,species,and place of *** statistical tests consisted of an ANOVA,Tukey means tests considering p≤0.05,and a Principal Components *** pleiacantha exhibited differences in terms of weight(f=54.79,p=0.001),length(f=90.83,p=0.001),thickness(f=104.89,p=0.001),and diameter(f=155.82,p=0.001),and the differences in Argemone mexicana were in weight(f=46.71,p=0.001),thickness(f=187.49,p=0.001),length(f=191.56,p=0.001),and diameter(f=215.83,p=0.001).The evaluated seeds reached their maximal imbibition velocity at 24 h of *** content of the micro-and macro-nutrients analyzed in the seeds and soil suggest a tight relation with the morphometric characteristics of the seeds.

关键词： Micronutrients agricultural area semiarid zone ecoregion buoyancy