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Geochemistry and mineralogy of beach sediments in the northern Gulf of Mexico,Tamaulipas state,Mexico:implication for provenance

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journal of Palaeogeography 2024年第3期13卷 375-400页

作者： Mayank Shukla Sanjeet K.Verma Mayla A.Ramos-Vázquez john S.Armstrong-Altrin Karla R.hernández-Martínez Sumit Mishra Vivek P.Malviya héctor hernández-Mendoza Posgrado de la Division de Geociencias Aplicadas Instituto Potosino de Investigacion Científica y Tecnologica(IPICYT)Camino a la Presa San José2055San Luis Potosí78216Mexico Division de Geociencias Aplicadas Instituto Potosino de Investigación Científica y Tecnologica(IPICYT)Camino a la Presa San Jose 2055San Luis Potosí78216Mexico Universidad Nacional Autonoma de México Instituto de Ciencias del Mar y LimnologíaUnidad de ProcesosOceanicos y CosterosCiudad UniversitariaCiudad de México 04510Mexico Department of Marine Sciences Bharathidasan UniversityTiruchirappalli620024Tamil NaduIndia Instituto de Geociencias Universidad Nacional Autonoma de MéxicoBoulevard Juriquilla 300176230JuriquillaQueretaroMexico Department of Applied Geology Dr.Harisingh Gour Central UniversitySagar470002Madhya PradeshIndia Instituto de Investigacion de Zonas Desérticas Universidad Autònoma de San Luis PotosíAltair 200CP 78377San LuisS.L.P.Mexico Universidad del Centro de Mexico Capitán Caldera 75CP 78250San LuisS.L.P.Mexico

Geochemical and mineralogical studies were performed in the la Pesca(lP)and Tesoro Altamira(TA)beach sediments,located in the Tamaulipas state,northern Gulf of *** main aim of this study is to infer the weathering history and provenance and to discriminate the tectonic environment of the beach *** sediments are composed of quartz with small amounts of accessory minerals such as plagioclase,calcite,orthoclase,microcline,and *** beach sediments are classified as fine-grained and very well sorted,however lP has coarse skewed and leptokurtic sediments,whereas TA has fine-skewed and very leptokurtic *** chemical index of weathering(CIW’)indicates intense weathering in the source *** quartz grain microtextures in the lP and TA are classified into mechanical,chemical,and mechanical/chemical *** features such as fractures,pits,percussion marks,abrasion fatigue,and V-shaped marks favor high-energy littoral,fluvial,subaqueous-marine,and aeolian *** chemical features indicate solution pits and crystalline overgrowth,which suggests a silica saturated marine *** mechanical/chemical features display adhering particles and elongated depressions suggest formation in a sub-aqueous nearshore marine *** and trace elements-based provenance discrimination diagrams indicate a felsic source derived from the Mesa Central(MC),Sierra Madre Oriental(SMOr)and Oaxaquia *** major and trace element concentrations imply a passive margin setting for the northern Gulf of Mexico,which is consistent with the general geology.

关键词： Beach sediments Geochemistry Mineralogy Provenance Tamaulipas Tectonic setting

learning to bag with a simulation‐free reinforcement learning framework for robots

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IET Cyber-Systems and Robotics 2024年第2期6卷 52-66页

作者： Francisco Munguia-Galeano jihong Zhu juan David hernández Ze ji Cooper Group University of LiverpoolLiverpoolUK School of Physics Engineering and Technology University of YorkYorkUK School of Computer Science and Informatics Cardiff UniversityCardiffUK School of Engineering Cardiff UniversityCardiffUK

Bagging is an essential skill that humans perform in their daily ***,deformable objects,such as bags,are complex for robots to manipulate.A learning-based framework that enables robots to learn bagging is *** novelty of this framework is its ability to learn and perform bagging without relying on *** learning process is accomplished through a reinforcement learning(Rl)algorithm introduced and designed to find the best grasping points of the bag based on a set of compact state *** framework utilises a set of primitive actions and represents the task in five *** our experiments,the framework reached 60% and 80% success rates after around 3 h of training in the real world when starting the bagging task from folded and unfolded states,***,the authors test the trained Rl model with eight more bags of different sizes to evaluate its generalisability.

关键词： reinforcement learning robot learning robotics

Accuracy of tree mapping based on hand-held laser scanning comparing leaf-on and leaf-off conditions in mixed forests

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journal of Forestry Research 2024年第5期35卷 14-25页

作者： Frederico Tupinambá-Simões Adrián Pascual juan Guerra-hernández Cristóbal Ordóñez Tiago de Conto Felipe Bravo iuFOR Sustainable Forest Management Research InstituteUniversity of Valladolid&INIAValladolidSpain Department of Geographical Sciences University of MarylandCollege ParkMD 20742USA Forest Research Centre School of AgricultureUniversity of LisbonTapada da Ajuda1349‑017 LisbonPortugal

The use of mobile laser scanning to survey forest ecosystems is a promising,scalable technology to describe forest 3D structures at high *** confirm the con-sistency in the retrieval of forest structural parameters using hand-held laser scanning(hlS),before operationalizing the method,confirming the data is *** analyzed the per-formance of tree-level mapping based on hlS under differ-ent phenology conditions on a mixed forest in western Spain comprising Pinus pinaster and two deciduous species,Alnus glutinosa and Quercus *** area was surveyed twice during the growing season(july 2022)and once in the deciduous season(February 2022)using several scan-ning *** reference data(418 trees,15 snags)was used to calibrate the hlS data and to assess the influence of phenology when converting 3D data into tree-level attrib-utes(DBh,height and volume).The hlS-based workflow was robust at isolating tree positions and recognizing stems despite changes in ***-six percent of all pairs matched below 65 *** DBh,phenology barely altered *** observed a strong agreement when comparing hlS-based tree height *** values exceeded 2 m when comparing height measurements,confirming height data should be carefully used as reference in remote sensing-based inventories,especially for deciduous *** volume was more precise for pines(r=0.95,and rela-tive RMSE=21.3–23.8%)compared to deciduous species(r=0.91–0.96,and relative RMSE=27.3–30.5%).hlS data and the forest structural complexity tool performed remark-ably,especially in tree positioning considering mixed forests and mixed phenology conditions.

关键词： Precision forestry Forest monitoring Mobile laser scanning Forest inventory

DNA metabarcoding reveals seasonal changes in diet composition across four arthropod-eating lizard species(Phrynosomatidae:Sceloporus)

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Integrative Zoology 2024年第3期19卷 480-495页

作者： Mauricio hernÁndez Stephanie hEREIRA-PAChECO Antton AlBERDI Aníbal h.DÍAZ DE lA VEGA-PÉREZ Arturo ESTRADA-TORRES Sergio ANCONA Yendi E.NAVARRO-NOYA Doctorado en Ciencias Biológicas Centro Tlaxcala de Biología de la ConductaUniversidad Autónoma de TlaxcalaTlaxcalaMexico Estación Científica la Malinche Centro Tlaxcala de Biología de la ConductaUniversidad Autónoma de TlaxcalaTlaxcalaMexico Center for Evolutionary hologenomics The Globe InstituteUniversity of CopenhagenCopenhagenDenmark Consejo Nacional de Ciencia y Tecnología-Centro Tlaxcala de Biología de la Conducta Universidad Autónoma de TlaxcalaTlaxcalaMexico Departamento de Ecología Evolutiva Instituto de EcologíaUniversidad Nacional Autónoma de MéxicoMexico CityMexico laboratorio de Interacciones Bióticas Centro de Investigación en Ciencias BiológicasUniversidad Autónoma de TlaxcalaSan Felipe IxtacuixtlaTlaxcalaMexico

Diet composition and its ecological drivers are rarely investigated in coexisting closely related *** used a molecular approach to characterize the seasonal variation in diet composition in four spiny lizard species inhabiting a mountainous *** metabarcoding revealed that the lizards Sceloporus aeneus,***,***,and *** mostly consumed arthropods of the orders hemiptera,Araneae,hymenoptera,and *** terrestrial lizards *** and *** mostly predated ants and spiders,whereas the arboreal–saxicolous *** and saxicolous *** largely consumed grasshoppers and *** taxonomic and phylogenetic diversity of the prey was higher during the dry season than the rainy season,likely because reduced prey availability in the dry season forced lizards to diversify their diets to meet their nutritional *** and phylogenetic composition varied seasonally depending on the species,but only dietary composition varied with *** dietary turnover was greater in *** than in ***,suggesting site-specific seasonal variability in prey availability;no other differences among species were ***,which lives at the highest altitude in our study site,displayed interseasonal variation in diet *** differences were correlated with the species’feeding strategies and elevational distribution,which likely contributed to the coexistence of these lizard species in the studied geographic area and beyond.

关键词： arthropod-eating lizards diet breadth environmental barcoding mountainous ecosystem seasonal dietary shifts

Decorating crystalline YFe_(2-x)Al_(x) on the Mg_(60)la_(10)Ni_(20)Cu_(10) amorphous alloy as “hydrogen pump” to realize fast de/hydrogenation

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journal of Materials Science & Technology 2024年第6期173卷 72-79页

作者： l.j.huang h.Wang l.Z.Ouyang M.Zhu h.j.lin School of Materials Science and Engineering Key Laboratory of Advanced Energy Storage Materials of Guangdong ProvinceSouth China University of TechnologyGuangzhou 510641China Institute of Advanced Wear&Corrosion Resistance and Functional Materials Jinan UniversityGuangzhou 510632China

Mg-based amorphous alloys are one of the potential hydrogen storage materials but suffer from sluggish dehydrogenation/hydrogenation(de/hydrogenation)*** this work,as a new strategy,a hydrogen pump is built on the surface of amorphous alloys to solve this *** milling crystalline YFe_(2-x)Al_(x) hydrogen storage alloy with Mg_(60)la_(10)Ni_(20)Cu_(10) amorphous alloy,fine crystalline particles were seeded on amorphous alloy powder to form a“strawberry”*** to the TEM observation,a metallurgical bonding boundary formed between the Mg-based amorphous matrix and the Y-Fe-Al crystalline *** microstructure and de/hydrogenation kinetics investigation,the“hydrogen pump”effect of the seeded crystalline alloy was confirmed,which makes it much easier for the hydrogen to dissociate on and diffuse through the surface of the Mg-based amorphous *** such effect,the h absorption rate of Mg_(60)la_(10)Ni_(20)Cu_(10) amorphous alloy became almost eight times faster and it absorbs ~2.8 wt.% in 1 h at 130℃ under 4.5 MPa-h_(2).Further,fast hydrogenation can even achieve at 70℃ and the low-temperature dehydrogenation kinetics of the amorphous hydride can be also greatly *** present work proves that surface modification is of great importance for obtaining Mg-based amorphous alloy with ideal hydrogen storage performance.

关键词： hydrogen storage Mg-based amorphous alloy hydrogen pump Composite structure

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

On an isotropic porous solid cylinder:the analytical solution and sensitivity analysis of the pressure

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Applied Mathematics and Mechanics(English Edition) 2024年第9期45卷 1499-1522页

作者： h.ASGhARI l.MIllER R.PENTA j.MERODIO Departamento de Matematica Aplicada a las TIC ETS de Ingenieria de Sistemas InformaticosUniversidad Politecnica de MadridMadrid 28031Spain School of Mathematics and Statistics University of GlasgowGlasgow G128QQU.K.

Within this work,we perform a sensitivity analysis to determine the influence of the material input parameters on the pressure in an isotropic porous solid *** provide a step-by-step guide to obtain the analytical solution for a porous isotropic elastic cylinder in terms of the pressure,stresses,and elastic *** obtain the solution by performing a laplace transform on the governing equations,which are those of Biot's poroelasticity in cylindrical polar *** enforce radial boundary conditions and obtain the solution in the laplace transformed domain before reverting back to the time *** sensitivity analysis is then carried out,considering only the derived pressure *** analysis finds that the time t,Biot's modulus M,and Poisson's ratio ν have the highest influence on the pressure whereas the initial value of pressure P_(0) plays a very little role.

关键词： sensitivity analysis laplace transform cylindrical polar coordinate Biot's modulus cylinder

Generalized height-Diameter Models for Pinus montezumae lamb. and Pinus pseudostrobus lindl. Plantations in Michoacan, Mexico

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Open journal of Forestry 2024年第3期14卷 214-232页

作者： jonathan hernández-Ramos Valentín josé Reyes-hernández héctor Manuel De los Santos-Posadas Aurelio Manuel Fierros-González Enrique Buendía-Rodríguez Gerónimo Quiñonez-Barraza Instituto Nacional de Investigaciones Forestales Agrcolas y Pecuarias (INIFAP)-Campo Experimental Bajo Celaya Guanajuato Mxico Colegio de Postgraduados (COlPOS) Campus Montecillo Mxico INIFAP Campo Experimental Valle de Mxico Texcoco Mxico INIFAP Campo Experimental Valle del Guardiana Durango Mxico

Tree height (h) in a natural stand or forest plantation is a fundamental variable in management, and the use of mathematical expressions that estimate h as a function of diameter at breast height (d) or variables at the stand level is a valuable support tool in forest inventories. The objective was to fit and propose a generalized h-d model for Pinus montezumae and Pinus pseudostrobus established in forest plantations of Nuevo San juan Parangaricutiro, Michoacan, Mexico. Using nonlinear least squares (NlS), 10 generalized h-d models were fitted to 883 and 1226 pairs of h-d data from Pinus montezumae and Pinus pseudostrobus, respectively. The best model was refitted with the maximum likelihood mixed effects model (MEM) approach by including the site as a classification variable and a known variance structure. The Wang and Tang equation was selected as the best model with NlS;the MEM with an additive effect on two of its parameters and an exponential variance function improved the fit statistics for Pinus montezumae and Pinus pseudostrobus, respectively. The model validation showed equality of means among the estimates for both species and an independent subsample. The calibration of the MEM at the plot level was efficient and might increase the applicability of these results. The inclusion of dominant height in the MEM approach helped to reduce bias in the estimates and also to better explain the variability among plots.

关键词： Random Covariate Random Effects Variance Structure Forest Inventories Forest Management Mixed Models

Uncovering the hierarchical clusters in the heat-affected zone of an electron beam weldedα/βtitanium alloy joint

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journal of Materials Science & Technology 2024年第7期174卷 120-132页

作者： C.Xu X.h.Shao h.j.Yang M.lv h.Q.liu X.l.Ma Shenyang National laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Suzhou laboratory Suzhou 215028China Department of Mechanical Engineering Kyushu UniversityFukuoka 819-0395Japan Bay Area Center for Electron Microscopy Songshan Lake Materials LaboratoryDongguan 523808China

Using high-resolution transmission Kikuchi diffraction(TKD)and transmission electron microscopy(TEM),we examined the hierarchical clusters that form in situ in the heat-affected zone(hAZ),which are com-monly referred to as“ghost”structures,of bimodal titanium alloy Ti-5Al-2Sn-2Zr-4Mo-4Cr(wt%,TC17).The ghost structures are enriched with Al elements but poor in Mo and Cr compared to the surroundingβ*** results show that the ghost structure in middle-hAZ mainly consists ofα_(l)laths with a high-angle grain boundary,which exhibits the classic Burgers orientation relationship(BOR)with the host matrix,while it encircles theα_(P)grains in *** the ghost structure is evidenced to form via in-complete martensitic *** results further confirm that the ghost structure is composed ofαl and tinyβ_(l)laths with BOR,with the former being enriched with Al and poor with Cr and Mo,while the latter is the ***,twoα_(l)variant clusters with a check-mark morphology are fre-quently observed viewed along[0001]_(αl)//[110]_(βl)directions,which are dominated by the crystallographic and geometrical relationships betweenαandβ*** on the microstructural characterization,it is hypothesized that the ghost structure is transformed from the initialα_(P)phase,due to the coupling ef-fect of high thermal stress(which induces the formation of a large number of dislocations)and element diffusion caused by sudden temperature increase and plunge cooling in the hAZ during the welding pro-cess.

关键词： TC17 titanium alloy Electron beam welding(EBW) The ghost structure Transmission Kikuchi diffraction(TKD) Transmission electron microscopy(TEM)