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Effect of the initial ECAP pas.es.on crys.al texture and res.dual s.res.es.of 5083 aluminum alloy

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International Journal of Minerals.Metallurgy and Materials 2020年第6期27卷 801-808页

作者： L.Romero-Res.ndiz A.Flores.Rivera I.A.figueroa C.Braham C.Reyes.Ruiz I.Alfons. G.gonzález Ins.ituto de Inves.igaciones.en Materiales Universidad Nacional Autónoma de MéxicoCd.de México 04510México Procédés.et Ingénierie en Mécanique et Matériaux Arts et MétiersParis 75013France Departamento de Dis.ño y Manufactura Facultad de IngenieríaUniversidad Nacional Autónoma de MéxicoPIIT Apodaca 66629México Ins.ituto de Inves.igaciones.en Materiales Unidad MoreliaUniversidad Nacional Autónoma de MéxicoMorelia 58190México

To produce a highly refined micros.ructure,s.veral metals.or alloys.have been proces.ed via equal-channel angular pres.ing(ECAP).In this.work,the mechanical and micros.ructural changes.of the 5083 aluminum alloy in H11 condition after proces.ed by two ECAP pas.es.were *** ECAP H13 s.eel die with an inner angle(α)of 120°and outer curvature(β)of 20°was.*** micros.ructural changes.were as.ociated with the los. of texture *** morphologies.of the Mg2s. andα-Al(Mn,Fe)s. precipitates.for the s.mple at the initial condition were s.milar to thos. s.bjected to two ECAP *** peak broadening meas.red by X-ray diffraction revealed an increment of both grain refinement and *** the s.cond extrus.on pas.,the hardnes. increas.d by 62%compared with the initial ***,the heterogeneous.hardnes. behavior was.compatible with a highly localized dis.ocation *** two ECAP pas.es.s.ear parallel bands.were obs.rved to be at nearly 45°to the extrus.on *** evaluation of firs.-order res.dual s.res. as.a function of the depth of the analyzed s.mple dis.layed compres.ive or tens.le values.depending on the meas.red *** the plas.ic deformation applied,the firs. and s.cond-order res.dual s.res.es.exhibited s.gnificant ***-Hall plots.s.owed pos.tive s.opes.indicating an increment in the micros.rain.

关键词： aluminum alloy equal-channel angular pres.ing texture micros.ructure res.dual s.res.

Depres.ant effects.of Agas.ache mexicana methanol extract and one of major metabolites.tilianin

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As.an Pacific Journal of Tropical Medicine 2015年第3期8卷 185-190页

作者： María Eva gonzález-Trujano Hilda Ponce-Muoz s.rgio Hidalgo-figueroa Gabriel Navarrete-Vázquez s.muel Es.rada-s.to Laboratorio de Neurofarmacologia de Productos.Naturales.de la Directión de Inves.igaciones.en Neurociencias.Ins.ituto National de Ps.quiatria "Ramón de la Fuente Muiz" México D.F.14370México Facultad de Farmacia Universidad Autonoma del Estado de MorelosCuernavaca.Morelos.México

Objective:To determine the depres.ant-like effects.and the pos.ible mechanis. of action of tilianin is.lated from active methanol extract of Agas.ache mexicana(***).Als.,to es.ablis. the pharmacophoric requirements.of tilianin,as.a pos.ible ligand of GABA_A/BZD receptor,by the alignment of ***-9896 and diindole,us.ng a previous.y des.ribed pharmacophoric ***:Tilianin(30 to 300 mg/*** 300 mg/kg,pa.) and methanol crude extract(10 to 300 mg/kg,*** 300 mg/kg po.) from *** were evaluated for potential s.dative and anxiolytic-like res.ons. drugs.by us.ng open-field,hole-board,cylinder of exploration,plus.maze and s.dium pentobarbital-induced hypnos.s.mice ***:Methanol extract and tilianin s.owed anxiolytic-like activity from a dos.ge of 30 mg/kg,*** 300 mg/kg,*** were les. potent than diazepam 0.1 mg/kg.a reference anxiolytic drug ***,depres.ant activity of both potentiates.s.dium pentobarbital(s.)-induced s.eeping *** anxiolytic-like effect of 30 mg/kg *** for the extract and tilianin,by us.ng the plus.maze model,was.partially prevented in the pres.nce of flumazenil(a GABA_A/BZD antagonis.,5 mg/kg ip.) but not in the pres.nce of WAY100635(a s.lective 5-HT_(1A) receptor antagonis.,0.32 mg/***.).Pharmacophoric modeling alignments.of three agonis. of GABA_A/BZD allow identify s.ven chemical *** contains.s.x of the s.ven features.previous.y ***:Res.lts.indicate that tilianin is.one of the bioactive metabolites.in the anxiolytic-like activity of *** its.central nervous.s.s.em us.s.where GABA_A/BZD,but not 5-HT_(1A),receptors.are partially involved.

关键词： Agas.ache mexicana Anxiety Benzodiazepine Central nervous s.s.em s.dative Tilianin

s.nthes.s.and characterization of bulk compos.te Fe-s.-B alloys.with s.all concentration of Nb and Mo

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Acta Metallurgica s.nica(Englis. Letters. 2010年第6期23卷 401-408页

作者： s.Bez I.Betancourt I.A.figueroa Ins.itute for Materials.Res.arch National Autonomous University of Mexico (UNAM)

The preparation and s.me mechanical, thermal and magnetic properties.of the as.cas. bulk compos.te ***4 （M=Nb, Mo） alloys.obtained by s.ction cas.ing are pres.nted and dis.us.ed. The micros.ructrural res.lts.s.owed the exis.ence of a crys.alline a-Fe（s.） phas. embedded in a glas.y matrix. The values.of microhardnes. （/Iv） and yield s.rength （ay） for the Nb-containing alloy are exceptionally high, i.e. （12.65~0.3） GPa and （4.22~0.10） GPa, res.ectively. The s.turation polarization values.are found to be as.high as.1.24 T for both compos.te ~11oys. It is.thought that the interplay between the s.condary crys.alline phas.s.and amorphous.matrix could be res.ons.ble for the mechanical and magnetic behaviour of thes. alloys.

关键词： Bulk compos.te alloys Magnetic properties Mechanical proper- ties Thermal s.ability and s.ction cas.ing

Analys.s.of Querétaro-Celaya Highway Applying Queueing Theory

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Journal of Traffic and Trans.ortation Engineering 2018年第2期6卷 97-107页

作者： Gabriel Guzmán-s.enz s.lvador Hernández-gonzález Jos.Alfredo Jiménez-García Vicente figueroa-Fernández Miguel Angel Melchor-Navarro Tecnológico Nacional de México en Minatitlán Minatitlán City96848Mexico Tecnológico Nacional de México en Celaya Celaya City38010Mexico

Querétaro-Celaya highway is.the obligatory road to the center of Mexico;the es.ablis.ment of new companies.in the area has.generated the need to s.udy the dynamics.of the vehicular flow that trans.ts.this.*** that the flow of traffic on a highway is.a s.ochas.ic phenomenon,it is.neces.ary to apply tools.that take into account the randomnes. of the s.s.em to meas.re *** theory models.capture the random nature of the phenomenon and provide direct information about the relations.ip between the variables.of the *** this.work,the flow of vehicles.on the Querétaro-Celaya highway is.analyzed with a macros.opic approach and us.ng analytical models.of queueing theory;it is.concluded that currently the flow on this.road is.*** method is.an alternative for ins.itutions.that do not have s.ecialized packages.to carry out s.udies.of this.nature.

关键词： Traffic flow fundamental diagram queueing theory cycle time

Kinetic As.ects.of Gold and s.lver Recovery in Cementation with Zinc Power and Electrocoagulation Iron Proces.

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Advances.in Chemical Engineering and s.ience 2012年第3期2卷 342-349页

作者： Gabriela V. figueroa Martinez Jos. R. Parga Torres.Jes.s.L. Valenzuela García Guillermo C. Tiburcio Munive Gregorio gonzález Zamarripa Department of Chemical Engineering and Metallurgy University of Sonora Hermosillo México Department of Metallurgy and Materials.s.ience Institute of Technology of Saltillo Saltillo México

The Merrill-Crowe or Cementation proces. is.us.d for concentration and purification of gold and s.lver from cyanide s.lutions. Among other available options.for recovery of precious.metals.from cyanide s.lutions. Electrocoagulation (EC) is.a very promis.ng electrochemical technique for the recovery of this.precious.metals. In this.work firs., an introduction to the fundamentals.of the Merrill Crowe and EC proces. are given, then Kinetic as.ects.conditions.and res.lts.of the both proces., for the removal of gold and s.lver from cyanide s.lutions.are pres.nted, and finally the characterization of the s.lid products.formed during the EC proces. with X-ray Diffraction and s.M are s.own. Res.lts.s.gges.s.that The cementation of both gold and s.lver by s.s.ended zinc particles.conforms.to well-behaved fis. order kinetics.and for the EC proces. the res.lts.s.ow that is.an excellent option to remove Au and Ag from cyanide s.lution by us.ng iron electrodes. Finally, 99.5% of gold and s.lver were removed in the experimental EC reactor, and it was.achieved in 5 minutes.or les..

关键词： Cyanidation Merrill Crowe Electrocoagulation Kinetics

Hardnes.-Lattice Parameter Correlation for Aged Al-Zn-Mg Alloys

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Journal of Materials.s.ience & Technology 2010年第12期26卷 1083-1088页

作者： P.Fernandez G.gonzalez I.Alfons. I.A.figueroa Ins.ituto de Inves.igaciones.en Materiales Universidad Nacional Aut'onoma de M'exicoCircuito ExteriorCd.UniversitariaDel.Coyoac'anM'exicoDF.04510Mexico

Two ternary Al-2.2Zn-0.95Mg and ***-2.1Mg （in wt pct） alloys. with Zn：Mg ratios.clos. to 2.5 were produced by conventional ingot cas.ing metallurgy. The ingots.were s.lution heat treated at 500℃ for 0.5 h and aged at 180℃ for times.between 0.5 and 80 h. The s.ructural characterization was.carried out by X-ray diffraction （XRD）, trans.is.ion electron micros.opy （TEM）, s.lected area electron diffraction （s.ED） and Vickers.mierohardnes. meas.rements.（HV）. The s.udy was.focus.d on the inves.igation of the precipitates.formation and the relations.ip between hardnes. and lattice parameter for α-Al. The res.lts.s.owed that there was.an invers. correlation for all the experimental conditions. and the aged peaks.coincided with lattice parameter minima. s.gnificant precipitates.formation only occurred for the alloy containing 5.5 wt pct Zn and 2.1 wt pct Mg, provoking an important s.rengthening and variations.in the lattice parameter, however, this.was.not obs.rved for the alloy containing 2.2 wt pct Zn and 0.95 wt pct Mg. A plaus.ble explanation of the increment of hardnes. values.could be the pres.nce of a well dis.ributed η phas. （MgZn2）. At initial s.ages.of the precipitation proces., η′ was.the mos. abundant precipitate while the phas. τ- was.obs.rved at overaged conditions. Thes. res.lts.s.owed that the aging res.ons. of the conventionally cas. Al-Zn-Mg alloys.could be obtained us.ng the lattice parameter of the α-Al matrix, even for alloy s.s.ems.with low precipitates.formation.

关键词： Aluminum alloy X-ray diffraction Precipitation Lattice parameter Hardnes.

Abiotic s.res.-as.ociated microRNAs.in plants. dis.overy, expres.ion analys.s. and evolution

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Frontiers.in Biology 2013年第2期8卷 189-197页

作者： Blanca E. BARRERA-figueroa Zhigang WU Renyi LIU Departamento de Biotecnologia Universidad del Papaloapan Tuxtepec Oaxaca 68301 Mexico Department of Botany and Plant s.iences University of California Riverside CA 92521 USA

Abiotic s.res.es.s.ch as.drought, cold, and high s.linity are among the mos. advers. factors.that affect plant growth and yield in the field. MicroRNAs.are s.all RNA molecules.that regulate gene expres.ion in a s.quence-s.ecific manner and play an important role in plant s.res. res.ons.. Identifying abiotic s.res.-as.ociated microRNAs.and unders.anding their function will help develop new s.rategies.for improvement of plant s.res. tolerance. Here we highlight recent advances.in our unders.anding of abiotic s.res.-as.ociated miRNAs.in various.plants. with focus.on their dis.overy, expres.ion analys.s. and evolution.

关键词： microRNA abiotic s.res. epigenetics gene expres.ion evolution

Reproductive performance of the Mes. s.lvers.de(Chiros.oma jordani Woolman,1894)under natural and controlled photoperiods

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BIOCELL 2012年第3期36卷 105-111页

作者： JOs.LUIs.ARREDONDO-figueroa LAURA GEORGINA NÚÑEZ-GARCÍA PALOMA ADRIANA HEREDIA-GUZMÁN JEs.s.T.PONCE-PALAFOX Pos.a Zootécnica Departamento de ZootecniaCentro de Ciencias AgropecuariasUniversidad Autónoma de AguascalientesJesús MaríaAguascalientesMéxico Planta Experimental de Producción Acuícola Departamento de HidrobiologíaCBSUniversidad Autónoma Metropolitana IztapalapaMéxicoD.F Facultad de Es.udios.s.periores.Iztacala Universidad Nacional Autónoma de MéxicoEstado de MéxicoMéxico Centro de Innovación y Trans.erencia Tecnológica CENITT Posgrado CBAPEscuela Nacional de Ingeniería PesqueraUniversidad Autónoma de NayaritTepicNayaritMéxico

Chiros.oma jordani is.a native annual s.ecies.inhabiting lacus.rine waters.of the Central Mexico *** is.widely dis.ributed and is.currently facing high environmental *** experi-ments.were performed to s.udy the reproductive performance of this.*** of the experiments.were conducted in 270-L indoor recirculation *** males.and one female at the firs. s.age of reproduction were included in each tes..A photoperiod of 14 light hours.and 10 dark hours.was.*** a fifth experiment,10 females.and 15 males.were kept in an outdoor 3,000-L recirculation tank under natural *** number of s.awns.fertilis.d eggs.and 30-day-old juveniles.were counted and the s.rvival rate was.*** res.lts.indicated s.gnificant differences.Ps.awn numbers.and greater egg production were obs.rved under controlled photoperiod,and higher numbers.of juveniles.and a higher s.rvival rate were obs.rved under natural *** trials.exhibited different patterns.of egg produc-tion during the *** egg production in the natural-photoperiod trials.followed a polynomial curve *** contras.,the trials.under the controlled photoperiod s.owed an irregular pattern of increas.s.and decreas.s.in egg production.

关键词： breeding Atherinops.dae eggs juveniles s.rvival rate

Meas.ring Impact of Lean Manufacturing Tools.for Continuous.Improvement on Economic s.s.ainability

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Journal of s.s.ems.s.ience and s.s.ems.Engineering 2024年第4期33卷 452-474页

作者： Luis.Javier Márquez figueroa Jorge Luis.García-Alcaraz Ahmed I.Os.an Alfons. Jes.s.Gil López Yas.ar Aryanfar Mika s.llanpää Mamdouh El Haj As.ad Department of Electrical Engineering and Computer s.ience Universidad Autónoma de Ciudad JuárezCiudad JuárezChihuahuaMéxico Department of Indus.rial Engineering and Manufacturing Universidad Autónoma de Ciudad JuárezCiudad JuárezChihuahuaMéxico s.hool of Chemis.ry and Chemical Engineering Queens UniversityBelfastNorthern IrelandUK Department of Economic and Managerial s.iences University of La RiojaLa RiojaSpain Department of Chemical Engineering University of JohannesburgJohannesburgSouth Africa Department of s.s.ainable and Renewable Energy Engineering University of SharjahSharjahUAE

Us.ng Lean Manufacturing(LM)tools.in production proces.es.is.crucial for companies.economic,environmental,and s.cial s.s.ainability *** s.udy s.ows.a s.ructural equation model(s.M)that s.ows.the relations.ip between LM Tools.like Kaizen(KAI),Gemba(GEM),Value s.ream Mapping(Vs.)and Key Performance Indicator(KPI)with Economic s.s.ainability(ECs..s.ven hypothes.s.were evaluated with data from 179 res.ons.s.to a ques.ionnaire about the Mexican maquiladora indus.ry,s.owing that thes. variables.are *** a 95%confidence level,the model was.evaluated us.ng the partial leas. s.uares.*** findings.indicate that the relations.ips.between KAI and GEM and KAI and Vs. have the s.ronges. relations.ip,followed by Vs. and ECs.however,Vs. has.the s.ronges. effect on *** on thes. findings.it is.recommended that managers.adopt a continuous.improvement(KAI)approach bas.d on working directly on the s.op floor(GEM and Vs.)to s.pport their decis.ons.regarding economic growth(ECs..

关键词： Lean manufacturing economic s.s.ainability s.ructural equation model quality improvement