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Understanding root-zone soil moisture in agricultural regions of Central Mexico using the ensemble Kalman filter,satellite-derived information,and the THEXMEX-18 dataset

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International Journal of Digital Earth 2022年第1期15卷 52-78页

作者： Héctor Ernesto Huerta-Bátiz Daniel Enrique Constantino-Recillas Alejandro Monsiváis-Huertero Juan Carlos Hernández-Sánchez Jasmeet Judge Ramón Sidonio Aparicio-García escuela superior de ingeniería mecánica y eléctrica unidad ticomán Instituto Politécnico NacionalMexico CityMexico escuela superior de ingeniería mecánica y eléctrica unidad Zacatenco Instituto Politécnico NacionalMexico CityMexico Tecnológico nacional de México-TESE EcatepecMexico department of Agricultural and Biological Engineering University of FloridaGainesvilleFLUSA

An Ensemble Kalman Filter(EnKF)-based assimilation algorithm was implemented to estimate root-zone soil moisture(RZSM)using a Soil-Vegetation-Atmosphere Transfer(SVAT)model during a complete growing season of corn in Central *** and field soil moisture(SM)observations and nASA SMAP SM retrievals were used to understand the effect of vertically spatial updates and uncertainties in meteorological forcings on RZSM *** of RZSM every 3 days using SM observations at 4 depths lowered the averaged standard deviation(ASD)and the root mean square error(RMSE)by 60%and 50%,respectively,compared to the open-loop *** assimilation of synthetic SM at the top 0-5 cm obtained RZSM closer to observations compared to THEXMEX-18 SM measurements and SMAP SM *** between EnKF estimates and SM observations and SMAP SM retrievals are mainly due to misrepresentation of vegetation *** results improved SM estimates up to 10-cm depth using SMAP SM retrievals;however,additional studies are needed to improve SM at deeper *** implemented methodology can estimate SM at the top 10 cm of the soil every 3 days to mitigate the impact of the climate change on agricultural production over rainfed areas,particularly in developing countries.

关键词： Root-zone soil moisture SVAT model ensemble kalman filter soil moisture active-Passive(SMAP)mission agricultural region THEXMEX-18 central Mexico

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Influence of oxidation of automatic transmission fluids (ATFs) and sliding distance on friction coefficients of a wet clutch in the running-in stage

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Friction 2021年第2期9卷 401-414页

作者： Leonardo Israel FARFAn-CABRERA Ezequiel Alberto GALLARDO-HERnÁndeZ Manuel VITE-TORRES Jesús Gilberto GODÍnEZ-SALCEDO Tecnologico de Monterrey Escuela de Ingeniería y CienciasAve.Eugenio Garza Sada 2501Monterrey 64849México Instituto Politécnico nacional SEPI-Escuela Superior de Ingeniería Mecánica y EléctricaUnidad ZacatencoGrupo de TribologíaCol.LindavistaCiudad de México 07738México Instituto Politécnico nacional ESIQIEIPNCol.LindavistaCiudad de México 07738México

In this paper,the influence of oxidation of automatic transmission fluids(ATFs)and sliding distance on the friction coefficients of a wet clutch in approached running-in conditions was *** ATFs were oxidized by a laboratory process approaching oxidation occurred in actual *** was evaluated by means of increase in carbonyl compounds and depletion of zinc dialkyldithiophosphates(ZDDPs)***,the changes in kinematic viscosity and viscosity index were ***-ondisk tests were conducted to replicate the actual sliding contact in a wet *** pin specimens were cut from friction material composite plates and the disks were actual steel separators both from an automotive wet *** coefficient, μ,was measured at progressive sliding velocity,ν,to obtain μ–νcurves at 26 and 100°*** μ–νtests were consecutively run using the same pair of specimens and *** cumulative sliding distance for each μ–νtest generated surface flattening using the *** friction coefficients of the wet clutch increased due to the ATFs oxidation meanwhile the dm/dv values decreased in most *** suggests that ATF oxidation can enhance torque capacity of the wet clutch,but it could reduce anti-shudder *** sliding distance improved the slopes in the μ–νresults using fresh ATFs meanwhile it generated a slope decrease by using aged ATFs.

关键词： wet clutch friction oil oxidation automatic transmission fluid(ATF)

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Brief Review of numerical Simulation Applied to Solve Oil Extraction Problems

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International Journal of Geosciences 2015年第5期6卷 504-536页

作者： M.M.Onofre-Ramos L.Castaneda E.Austria-Aguilar E.E.Hernández-Martínez A.Oropeza-Osornio escuela superior de ingeniería mecánica y eléctrica unidad ticomán Instituto Politécnico NacionalMéxico D.F.México

In the last decades, the numerical analysis has abridged the time and cost of oil extractive operations, and thus their implementation has been promoted so much that today is used to solve a large number of phenomena that occur during the extraction of hydrocarbons, not only economizing the operation, but also shedding light to the phenomenon, and helping to have a better understanding. nevertheless in spite of the success of the applications of numerical simulations, it has been until today, looking for their optimization, because the discretization methods of the domain and the model are through meshes, which require modifying the physics of the problem so that this matches the numerical method, and not in backwards.

关键词： numerical Simulation Oil Reservoir Smooth Particle Hydrodynamics

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Coherent States for the Two-Dimensional Dirac-Moshinsky Oscillator Coupled to an External Magnetic Field

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Communications in Theoretical Physics 2015年第3期63卷 271-274页

作者： D.Ojeda-Guillen R.D.Mota V.D.Granados escuela superior de Física y Matemáticas Instituto Politécnico NacionalEd.9Unidad Profesional Adolfo López MateosC.P.07738México D.F.Mexico escuela superior de ingeniería mecánica y eléctrica Unidad CulhuacánInstituto Politécnico NacionalAv.Santa Ana No.1000Col.San Francisco CulhuacánDelegación CoyoacánC.P.04430Mexico D.F.Mexico

We show that the（2＋1）-dimensional Dirac-Moshinsky oscillator coupled to an externa/ magnetic field can be treated algebraically with the SU（1,1） group theory and its group *** use the su（1,1） irreducible representation theory to find the energy spectrum and the ***,with the su（1,1） group basis we construct the relativistic coherent states in a closed form for this problem.

关键词： Lie algebras coherent states Dirac equation Dirac-Moshinsky oscillator

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near shore seismic movements induced by seaquakes using the boundary element method

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Earthquake Engineering and Engineering Vibration 2017年第3期16卷 571-585页

作者： Alejandro Rodríguez-Castellanos Manuel Carbajal-Romero norberto Flores-Guzmán J.Efraín Rodríguez-Sánchez Andriy Kryvko instituto mexicano del petróleo eje central lázaro cárdenas 152Gustavo A.MaderoDistrito FederalMéxico escuela superior de ingeniería mecánicay eléctrica instituto politécnico nacionalupalmEdif.5Av.Instituto Politécnico Nacional S/NCol.LindavistaGustavo A.MaderoDistrito FederalMéxico escuela superior de ingeniería mecánicay eléctrica instituto politécnico nacionalunidad profesional azcapotzalcoDistrito FederalMéxico centro de investigación en matemáticas jalisco s/nmineral de valencianaguanajuatoMéxico

This study quantifies seismic amplifications in near-shore arising from seaquakes. Within the Boundary element Method, boundary elements are used to irradiate waves and force densities obtained for each element. Huygens′ Principle is implemented since the diffracted waves are constructed at the boundary from which they are radiated, which is equivalent to Somigliana′s theorem. Application of boundary conditions leads to a system of integral equations of the Fredholm type of second kind and zero order. Several numerical configurations are analyzed： The first is used to verify the present formulation with ideal sea floor configurations to estimate seismic amplifications. With the formulation verified, simple slope configurations are studied to estimate spectra of seismic motions. It is found that P-waves can produce seismic amplifications from 1.2 to 3.9 times the amplitude of the incident wave. SV-waves can generate seismic amplifications up to 4.5 times the incident wave. Another relevant finding is that the highest amplifications are at the shore compared to the ones at the sea floor.

关键词： seismic amplifications seaquake earthquake elastic waves boundary element method near shore cities

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Analysis of the Behavior of a Turbomachine Driven by a Compressed Air System

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Journal of Power and Energy Engineering 2017年第5期5卷 1-13页

作者： Miguel Toledo-Velázquez Raúl Cruz-Vicencio Juan Abugaber-Francis Juan Carlos Anzelmetti-Zaragoza Instituto Politécnico nacional Escuela Superior de Ingeniería Mecánica y Eléctrica Sección de Estudios de Posgrado e Investigación Laboratorio de Ingeniería Térmica e Hidráulica Aplicada (LABINTHAP) Unidad Profesional “Adolfo López Mateos” Ciudad de México México Universidad Veracruzana Escuela de Ingeniería Mecánica y Eléctrica Unidad Poza Rica-Tuxpan Veracruz México

Different experiments in high speed turbomachines require expensive and sophisticated infrastructure to implement their impulsion and reach high regimes. In developed countries, this can be achieved by using aeroderivative gas turbines or DC motors of about 400 HP. This paper presents an experimental system designed and built with the intention of performing behavior studies in test turbomachinery. The proposed installation uses compressed air as driving fluid, which allows the turbomachinery to reach high rotational speeds where very important phenomena occur. An analysis is carried out considering the rotational speed behavior of an internal combustion engine turbocharger of the Perkins series when it is driven by pressures ranging from 4.2 kg/cm2 to zero. Additionally, another experiment couples an automotive electrical generator with the turbine to observe the system operation when a load is applied. The behavior of the pressure is analyzed when it is in function of the time of air discharge that goes from a compressed air storage tank to the turbocharger for its impulsion. This is an experimental system that can be designed and constructed economically within the bounds of any public university.

关键词： Turbomachinery Compressed air Turbocharger Vorticity

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Microstructural evaluation and nanohardness of an AlCoCuCrFeniTi high-entropy alloy

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International Journal of Minerals,Metallurgy and Materials 2019年第5期26卷 634-641页

作者： C.D.Gómez-Esparza R.Peréz-Bustamante J.M.Alvarado-Orozco J.Mu?oz-Salda?a R.Martínez-Sánchez J.M.Olivares-Ramírez A.Duarte-Moller Centro de Investigación en Materiales Avanzados (CIMAV) Laboratorio Nacional de Nanotecnología COnACyT-Corporación Mexicana de Investigación en Materiales S.A.de C.V.(COMIMSA) Centro de ingeniería y desarrollo Industrial Querétaro Campus Centro de Investigación y de Estudios Avanzados del IPn Unidad Querétaro Universidad Tecnológica de San Juan del Río escuela de ingeniería Civil Industrialy Mecánica Universidad De La Salle Bajío

An AlCoCuCrFeniTi high-entropy alloy(HEA) was prepared by mechanical alloying and sintering to study the effect of Ti addition to the widely studied AlCoCuCrFeni system. The structural and microstructural characteristics were investigated by X-ray diffraction(XRD), scanning electron microscopy(SEM), and transmission electron microscopy(TEM). The formation of four micrometric phases was detected: a Cu-rich phase with a face-centered cubic(fcc) structure, a body-centered cubic(bcc) solid solution with Cu-rich plate-like precipitates(fcc), an ordered bcc phase, and a tetragonal structure. The XRD patterns corroborate the presence of a mixture of bcc-, fcc-, and tetragonal-structured phases. The Vickers hardness of the alloy under study was more than twice that of the AlCoCuCrFeni alloy. nanoindentation tests were performed to evaluate the mechanical response of the individual phases to elucidate the relationship between chemical composition, crystal structure, and mechanical performance of the multiphase microstructure of the AlCoCuCrFeniTi HEA.

关键词： high-entropy alloys mechanical alloying microstructure nanoindentation

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Geochemical elements in suspended particulate matter of Ensenada de La Paz Lagoon,Baja California Peninsula,Mexico:Sources,distribution,mass balance and ecotoxicological risks

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Journal of Environmental Sciences 2024年第2期136卷 422-436页

作者： Sandra Soledad Morales-García Pilar de Acacia Pérez-Escamilla Suresh Babu Sujitha Pichaimani Godwyn-Paulson Andrés Felipe Zuniga-Cabezas Muthuswamy Ponniah Jonathan Instituto Politécnico nacional(IPn) Centro Mexicano para la Producción más Limpia(CMPL)Av.Acueducto s/nCol.Barrio la Laguna TicománDel Gustavo A.MaderoC.P.07340Ciudad de MéxicoMexico Instituto Politécnico nacional(IPn) Escuela Superior de Ingeniería y Arquitectura(ESIA)Unidad Ticomán***án 600Delg.Gustavo A.MaderoC.P.07340Ciudad de México(CDMX)Mexico Instituto Politécnico nacional(IPn) Centro Interdisciplinario de Investigaciones y Estudios sobre Medio Ambiente y Desarrollo(CIIEMAD)Calle 30 de Junio de 1520Barrio la Laguna TicománDel.Gustavo A.MaderoC.P.07340Ciudad de MéxicoMéxico

The present study aimed to evaluate multi-element concentrations(Al,As,Ca,Cd,Co,Cr,Cu,Fe,Mg,Mn,Mo,ni,Pb,Sr)in suspended particulate material(SPM)collected from Ensenada de La Paz(elP)lagoon,Baja California Sur,Mexico in two different periods(September and May)to comprehend their origin,geochemical behavior,mass transfer and associated ecotoxicological *** 24 hr variation coefficient of volumetric SPM levels were found to be 51.7%in September and 40.5%in May,signifying the effects of oceanic *** calculated enrichment factor(EF)values for all the studied elements were of higher magnitude because of the high surface area and oxide nature of SPM,and in this study,Mo had the highest EF of 46.77 probably due to its origin from continental *** the ecotoxicological perspective,the integrated toxic risk index revealed low toxic risk to the benthic ***,the mean-ERM-Quotient calculated using the particulate concentrations of As,Cd,Cr,Cu,ni,Pb indicated 9%probability of toxicity to *** comprehensive geochemical and ecotoxicological assessment of particulate metal concentrations in the elP lagoon signify low to moderate contamination.

关键词： Suspended particulate material Heavy metals Risk assessment Mass transfer Ensenada de La Paz

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Modelling fuel loads of understorey vegetation and forest floor components in pine stands in nW Spain

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Forest Ecosystems 2022年第6期9卷 775-789页

作者： Jose A.Vega Stefano Arellano-Perez Juan Gabriel Alvarez-Gonzalez Cristina Fernandez Enrique Jimenez Pedro Cuinas Jose María Fernandez-Alonso Daniel J.Vega-nieva Fernando Castedo-Dorado Cecilia Alonso-Rego Teresa Fontúrbel Ana Daría Ruiz-Gonzalez Centro de Investigacion Forestal de Lourizan PO Box 12736080PontevedraSpain unidad de Gestion Ambiental y Forestal Sostenible(UXAFORES) Departamento de Ingeniería AgroforestalEscuela Politecnica Superior de IngenieríaUniversidad de Santiago de CompostelaCampus Universitario s/n27002LugoSpain Facultad de Ciencias Forestales Universidad Juarez del Estado de DurangoRío Papaloapan y Blvd.Durango s/nCol.Valle del Sur34120DurangoMexico departamento de ingeniería y Ciencias Agrarias Universidad de LeonCampus de Ponferrada24401PonferradaSpain

In this study,310 destructively sampled plots were used to develop two equation systems for the three main pine species in nW Spain(***;*** and ***):one for estimating loads of understorey fuel components by size and condition(live and dead)and another one for forest floor *** systems of equations were simultaneously fitted for estimating fuel loads using overstorey,understorey and forest floor variables as *** systems of equations included both the effect of pine species and the effect of understorey compositions dominated by ferns-brambles or by woody species,due to their obvious structural and physiological *** general,the goodness-of-fit statistics indicated that the estimates were reasonably robust and accurate for all of the fuel *** best results were obtained for total understorey vegetation,total forest floor and raw humus fuel loads,with more than 76%of the observed variability explained,whereas the poorest results were obtained for coarse fuel loads of understory vegetation with a 53%of observed variability *** reduce the overall costs associated with the field inventories necessary for operational use of the models,the additive systems were fitted again using only overstorey variables as potential *** relationships for fine(nd total understorey vegetation and total forest floor fuel loads were obtained,indicating the complexity of the forest overstorey-understorey and overstorey-forest floor ***,these models explained around 52%of the observed ***,equations estimating the total understorey vegetation and the total forest floor fuel loads based only on canopy cover were *** models explained only 26%-32%of the observed variability;however,their main advantage is that although understorey vegetation in forested landscapes is largely invisible to remote sensing,canopy cover can be estimated with moderate accuracy,allowin

关键词： Area-based approach Additive equation systems Live and dead fine fuel Pinus pinaster Pinus radiata Pinus sylvestris

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Hydrothermal synthesis of pyrrhotite(Fex-1S) nanoplates and their antibacterial, cytotoxic activity study

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Progress in natural Science:Materials International 2018年第4期28卷 447-455页

作者： Liliana Argueta-Figueroa nayely Torres-Gómez René García-Contreras A.R.Vilchis-nestor O.Martínez-Alvarez L.S.Acosta-Torres M.C.Arenas-Arrocena Laboratorio de Investigación Interdisciplinaria área de Nanoestructuras y Biomateriales Escuela Nacional de Estudios Superiores Unidad León Universidad Nacional Autónoma de México Centro Conjunto de Investigación en Química Sustentable (CCIQS) UEAMex-UNAM departamento de ingeniería en Energía Universidad Politécnica de Guanajuato

The aim of this study was to synthesize and characterize Fex-1S 2D-nanostructures with pyrrhotite phase,as well as to explore their biological(antibacterial and cytotoxic)properties,namely the expression of reactive oxygen species(ROS)in the exposure of cells and *** on hydrothermal synthesis,the characterization of asprepared 2D-nanostructures was performed by XRD,SEM,EDS,and TEM,in which the single-crystalline pyrrhotite phased Fex-1S nanoplate morphology was *** antibacterial activities of Fex-1S nanoplates against human pathogenic strains such as Staphylococcus aureus,Escherichia coli,and Enterococcus faecalis were *** inhibitory concentration(MIC)and minimum bactericidal concentration(MBC)were determined following the broth microdilution *** and expression of intracellular ROS of pyrrhotite nanoplates on Human Gingival Fibroblast(HGF),Human Pulp Cells(HPC)and Human Osteoblast(HBC)were *** viability was determined by the MTT *** experiments were performed of three independent experiments and data were analyzed by Kruskal-Wallis and Mann-Whitney tests,also Pearson′s Correlation was *** nanoplates exhibited good bactericidal *** types of cells tested showed slight *** was found that intracellular ROS is produced when cells and bacteria tested are exposed to pyrrhotite nanoplates in presence of both air and peroxide *** production levels were higher in the bacteria than the cells exposed to these nanoplates.

关键词： Hydrothermal synthesis Iron sulfide nanoplates Minimal inhibitory concentration Antibacterial effect Cytotoxicity assay

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