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A Numerical Solution for the Integrated Analysis of Water Resources Management: Application to the Mero River Watershed, La Coruña, Spain

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j.urnal of Water Resource and Protection 2015年第10期7卷 815-829页

作者： Francisco Padilla j. Horacio hernández Ricardo j.ncosa Pablo R. Vellando Water and Environmental Engineering Group ETS de Ingenieros de Caminos Canales y Puertos Campus de Elvi&#241 a University of A Coru&#241 a A Coru&#241 a Spain Ingeniería Geomática e Hidráulica Universidad de Guanajuato Guanajuato Mexico

This research is concerned with new developments and practical applications of a physically-based numerical model that incorporates new approaches for a finite elements solution to the steady/transient problems of the j.int ground/surface water flows. Python scripts are implemented in Geographic Information System (GIS) to store, represent and take decisions on the simulated conditions related to the water resources management at the scale of the watershed. The proposed surface-subsurface model considers surface and groundwater interactions to be 2-D horizontally distributed and depth-averaged through a diffusive wave approach for surface flood routing. Infiltration rates, overland flows and evapotranspiration processes are considered by a diffuse discharge from surface water, non-saturated subsoil and groundwater table. Recent developments also allow for the management of surface water flow control through the capacity of diversion on river beds, spillways and outflow operations of floodgates in weirs and dams of reservoirs. Practical application regards the actual hydrology of the Mero River watershed, with two important water bodies mainly concerned with the water resources management at the Cecebre Reservoir and the present flooding of a deep coal mining excavation. The MELEF model (Modèle d’éLéments Fluides, in French) was adapted and calibrated during a period of five years (2008/ 2012) with the help of hydrological parameters, registered flow rates, water levels and registered precipitation, water uses and water management operations in surface and groundwater bodies. The results predict the likely evolution of the Cecebre Reservoir, the flow rates in rivers, the flooding of the Meirama open pit and the local water balances for different hydrological components.

关键词： Integrated Surface/Subsurface Flows Numerical Modelling Finite Elements Watershed Hydrology Geographic Information System Water Resources Management

Appraisal of Surface Modified AISI 316 L Stainless Steels by Plasma and Solid Nitriding Techniques

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Materials Sciences and Applications 2020年第7期11卷 462-473页

作者： R. Guardian I. Rosales-Cadena j. L. Valle-Mata j. Pereyra-hernández O. Ocampo Center of Research in Engineering and Applied Science CIICAp - UAEM. Cuernavaca Mexico

AISI 316 L stainless steels type was surface modified by ion and solid nitriding treatment. It was demonstrated that a surface activation pretreatment in samples based in acid mixture accompanied with NH4NO3 solution inside the container, can produce an efficient nitrogen diffusion process. As compared with ion nitriding treatment (20%N2-80%H2), the samples were treated with solid nitriding technique, using Fe4KCN based compound at the same time and temperature (6 h and 500°C respectively). Superficial layers with a depth of 45 μm average were obtained with six hours treatment. Hardness surface values of two surface treatments present an increased value of approximately three times with respect to the matrix sample. Wear evaluation indicated low regimes of weight losses for both treatments. Oxidative-adhesive result is to be the predominant operating wear mechanism. Positive results were obtained in solid nitriding technique as compared with the expensive ion nitriding technique.

关键词： Surface Modification Hardness Mechanical Properties Wear

Steel Pitting Corrosion Analysis, Using a High Vaccum Epoxy Penetration Technique

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Materials Sciences and Applications 2013年第1期4卷 11-13页

作者： Gerardo Zavala Olivares Mónica j. hernández Gayosso Rafael García Esquivel Instituto Mexicano del Petróleo College of San Bartolo Atepehuacan México City México 2Petroleos Mexicanos Gas y Petroquímica Básica Subdirección de Ductos College of Huasteca México City México

An epoxy penetration technique was used to reproduce and analyze the pitting corrosion process occurred at a steel coupon surface. The samples were exposed to the resin under high vacuum conditions, in order to fulfill the pits caused by the corrosion process. With this technique, a 3D image of the corrosion damages was obtained. Once the image of the damaged surface was obtained, a Scanning Electron Microscope (SEM) was used to analyze the morphology of the pits exhibited by the steel sample. The results were satisfactory, as different parameters such as the diameter, shape and depth of the pits originated, along with the corrosion preferential path, could be established. According to the results, the use of the epoxy penetration technique may be considered as alternating pitting corrosion analysis technique.

关键词： Pitting Corrosion Analysis Epoxy Inj.ction

Synthesis and Characterization of Heat Treated Cu-Al alloys for Energy Applications

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j.urnal of Materials Science and Chemical Engineering 2019年第11期7卷 22-30页

作者： j. Pereyra-hernández O. Ocampo R. A. Falcon-Castrej.n I. Rosales-Cadena j. A. Ruiz-Ochoa Centro de Investigación en Ingeniería y Ciencias Aplicadas UAEM Chamilpa Cuernavaca Morelos México Facultad de Ciencias de la Ingeniería y Tecnología UABC Tijuana Baja California México

Three alloys with different atomic percent (at. %) Cu-Al were designed and synthetized, using an electromagnetic induction furnace system. Alloys were designed in a substitutional way, varying the Al content respect to Cu, from 10 to 50 at. %. Microstructure changes from dendritic structure to equiaxed grains depending the heat treatment. Hardness test evaluation has shown values in the order of 700 kg/mm2 which represents an increment of 600 percent, while compression tests have shown an important strengthening increment. Besides, electrical resistivity test was carried out, in order to analyze a future application in an electrochemical system, obtaining an improvement three times more in comparison with the unalloyed sample. Strengthening results were interpreted in terms of defects generation, caused by the thermal treatments.

关键词： Solid Solution Mechanical Properties Heat Treatments Electrical Properties

Constrained sintering and wear properties of Cu-WC composite coatings

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Transactions of Nonferrous Metals Society of China 2017年第10期27卷 2214-2224页

作者： j.L.CABEZAS-VILLA L.OLMOS H.j.VERGARA-hernáNDEZ O.j.MéNEZ P.GARNICA D.BOUVARD M.FLORES División de Estudios de Posgrado e Investigación TecNM/Instituto Tecnológico de MoreliaAv. Tecnológico #1500 Colonia Lomas de Santiaguito Morelia Michoacán C. P. 58120 México INICIT Universidad Michoacana de San Nicolás de HidalgoFco. J. Mujica S/N Morelia Michoacán C. P. 58060 México Universidad de Guadalaj.ra Departamento de Ingeniería de ProyectosJosé Guadalupe Zuno # 48 Los Belenes Zapopan Jalisco C. P. 45100 México Univ. Grenoble Alpes CNRS SIMaP 38000 Grenoble France

Coatings of metal matrix composites(Cu?WC)were fabricated by solid-state *** reinforcing particles indifferent quantities from5%up to30%(volume fraction)were mixed with Cu *** mixing,the powders were poured ontothe surface of copper *** was carried out at1000°C under a reducing atmosphere in a vertical *** was affected by both rigid substrates and WC particles which retarded the radial and axial densification of ***,the coatings were strongly attached to the substrate,and WC particles were randomly distributed within the *** addition ofthe reinforcing particles enhanced the microhardness and reduced the volume loss in wear tests to1/17compared to the *** predominant wear mechanism was identified as abrasion at a load of5N.20%WC(volume fraction)reinforcingparticles led to the maximum values of properties for the composite coating.

关键词： constrained sintering dilatometry dry sliding wear microhardness metal matrix composites coating

Application of the Weibull Distribution to Estimate the Volume of Water Pumping by a Windmill

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j.urnal of Power and Energy Engineering 2016年第9期4卷 36-51页

作者： M. Toledo Velázquez j. herná ndez Rodrí guez M. Vega Del Carmen F. E. Flores Murrieta G. Tolentino Eslava Laboratorio de Ingenierí a Té rmica e Hidrá ulica Aplicada (LABINTHAP) IPN-SEPI-ESIME Zacatenco Ciudad de M&eacute xico M&eacute xico Divisió n de Ciencias e Ingenierí a Laboratorio en Sistemas de Energ&iacute a Universidad de Quintana Roo Chetumal M&eacute xico

Given the steady increase in use of alternative energy sources to supply part of the energy demand of the world, and considering that Mexico has enough wind resources to produce all the electricity required by the country, in this work, it is carried out the development of a system of wind resource assessment to determine the volume of water that a windmill pumping system can provide in a specific area. To this end, it has developed a computer program for wind resource assessment by measurements of wind speed, direction, temperature, barometric pressure and relative humidity. Measuring equipments were mounted in a wind measurement tower of 10 m high, within the premises of the University of Quintana Roo which is located along the coast. Until this day, there are records over a period of five months of the variables of wind speed, wind direction, temperature, relative humidity and atmospheric pressure. These variables were used for statistical calculations using the Weibull distributions. To give a better use of the calculated data, they were applied to the evaluation of a Pumping System.

关键词： Pumping Systems Weibull Distribution Wind Energy Windmill

Chemical, Starch Digestibility and Sensory Characteristics of Durum Wheat/Unripe Whole Banana Flour Blends for Spaghetti Formulation

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Food and Nutrition Sciences 2014年第3期5卷 264-270页

作者： Perla Osorio-Díaz j.sé j. Islas-hernández Edith Agama-Acevedo Sandra L. Rodríguez-Ambriz María E. Sánchez-Pardo Luis A. Bello-Pérez Center for Development of Biotic Products National Polytechnique Institute Yautepec México National School of Biological Sciences National Polytechnique Institute México D.F. México.

Excess weight and obesity are serious public health problems, which should be addressed through encouraging the consumption of foods with high amount of low digestible carbohydrates. The obj.ctive of this study was to put together spaghetti that blends unripe banana whole flour (UBWF) and durum wheat of different levels and to evaluate their chemical composition, starch digestibility and sensory characteristics. Spaghetti with 15%, 30%, and 45% of UBWF and a control spaghetti (100% durum wheat flour) were put together. The protein content decreased (10.42% to 7.74%) as the UBWF level was increased in the composite, while the amount of ash (0.87% to 1.54%) and total starch (70.24% to 73.71%) increased. Spaghetti with 15% and 45% of UBWF had similar available starch content. The addition of UBWF increased the resistant starch content from 1.98% to 10.91%, and consequently the indigestible starch fraction (14.00% to 27.29%). Spaghetti with 30% of UBWF had good consumer acceptability and was ranked higher than the control sample.

关键词： Starch Digestibility Banana Spaghetti Indigestible Fractio

Apples to oranges:environmentally derived,dynamic regulation of serotonin neuron subpopulations in adulthood?

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Neural Regeneration Research 2025年第9期20卷 2596-2597页

作者： Christopher j.O’Connell Matthew j.Robson Department of Genetics College of MedicineHarvard UniversityBostonMAUSA j.mes L.Winkle College of Pharmacy Division of Pharmaceutical SciencesUniversity of CincinnatiCincinnatiOHUSA Neuroscience Graduate Program College of MedicineUniversity of CincinnatiCincinnatiOHUSA

Traumatic brain inj.ry(TBI)is a public health problem with an undue economic burden that impacts nearly every age,ethnic,and gender group across the globe(Capizzi et al.,2020).TBIs are often sustained during a dynamic range of exposures to energetic environmental forces and as such outcomes are typically heterogeneous regarding severity and pathology(Capizzi et al.,2020).

关键词： sustained orange dynamic

Consolidation of AA 7075-2 wt% ZrO2 Composite Powders by Severe Plastic Deformation via ECAP

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Acta Metallurgica Sinica(English Letters) 2016年第10期29卷 895-901页

作者： S. E. hernandez-Martinez j. j. Cruz-Rivera R. Martinez-Sanchez C. G. Garay-Reyes j. A. Mufioz-Bolanos j. M. Cabrera j.L.hernández-Rivera Instituto de Metalurgia Universidad Autonoma de San Luis Potosi Sierra Leona 550 78210 San Luis Potosi Mexico Centro de Investigacion en Materiales Avanzados (CIMAV) Miguel de Cervantes 120 31109 Chihuahua Mexico Departamento de Ciencia de Materiales e Ingenieria Metalurgica Universitat Politecnica de Catalunya Av Diagonal 647 08028 Barcelona Spain Fundacion CTM Centro Tecnologico Plaza de la Ciencia 208243 Manresa Spain CONACYT Research Fellow-Instituto de Metalurgia Universidad Autonoma de San Luis Potosi- Sierra Leona 550 78210 San Luis Potosf Mexico

The powders of the AA 7075-ZRO2 were mixed by mechanical milling, but it was found that the system presents a few disadvantages when processed by conventional sintering and hot extrusion, since intermetallic phases between ZrO2 particles and alloying elements were formed. Equal channel angular pressing （ECAP） processing was proposed as an alternative method to consolidate the composite where there is no intermetallic formation. The analysis of the ECAP process showed that the intermediate temperature （220℃） produced a higher consolidation level than conventional sintering and hot extrusion （400 and 500℃, respectively）. This fact was supported by relative density analysis. In the case of the sintered and hot-extruded sample, the relative density exhibited a value of 0.95, while ECAP sample showed a value of 0.98. Hardness values show that microstructural refinement obtained during mechanical milling was preserved during ECAP processing even when it was carded out at 220℃.

关键词： Metal matrix composites (MMCs) Powder consolidation Severe plastic deformation (SPD)