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Corrosion Behavior of Ψ and β Quasicrystalline Al–Cu–Fe Alloy

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Acta Metallurgica Sinica(English Letters) 2015年第9期28卷 1117-1122页

作者： Alvaro torres Sergio Serna Cristobal Patio Gerardo Rosas Facultad de Ciencias Químicas e Ingeniería P.A. Ing.Mecnica UAEM Av. Universidad 1001 Col. Chamilpa62210 Cuernavaca Mor. Mexico Centro de Investigación en Ingeniería y Ciencias Aplicadas UAEM Av. Universidad 1001 Col. Chamilpa62210 Cuernavaca Mor. Mexico Facultad de Ingeniería Universidad Autónoma del CarmenCampus Ⅲ Avenida Central S/N Esq. con Fracc. MundoMaya C.P. 24115 Ciudad del Carmen Campeche Mexico Instituto de Investigaciones Metalurgicas UMSNH Edificio U. Ciudad Universitaria Morelia Mich. 58000 Mexico

Two nanostructured A1-Cu-Fe alloys, A164Cu24Fe12 and A162.5Cu25.2Fe12.3, have been studied. Icosahedral quasicrystalline （ψ） A164CH24FeI2 and crystalline cubic （ β） ***25.2Fe12.3 cylindrical ingots were first produced using normal casting techniques. High-energy mechanical milling was then conducted to obtain β icosahedral and β intermetallic nanostructured powders. Electrochemical impedance spectroscopy, linear polarization resistance, and potentiodynamic polarization were used to investigate the electrochemical corrosion characteristics of the powders in solutions with different pH values. Current density （icorr）, polarization resistance （Rp）, and impedance modulus （121） were determined. The results showed that regardless of pH value, increasing the solution temperature enhanced the corrosion resistance of the both phases. However, the electrochemical behavior of the phase indicated that its stability depends on the submerged exposure time in neutral and alkaline environments. This behavior was related to the type of corrosion products present on the surfaces of the particles along with the diffusion and charge-transfer mechanisms of the corrosion process.

关键词： Nano-quasicrystalline AI-Cu-Fe alloy Mechanical alloying Corrosion

Constrained Fractional Variational Problems of Variable Order

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IEEE/CAA Journal of Automatica Sinica 2017年第1期4卷 80-88页

作者： Dina Tavares Ricardo Almeida Delfim F.M.torres Department of Mathematics Polytechnic Institute of Leiria Department of Mathematics University of Aveiro

Isoperimetric problems consist in minimizing or maximizing a cost functional subject to an integral *** this work, we present two fractional isoperimetric problems where the Lagrangian depends on a combined Caputo derivative of variable fractional order and we present a new variational problem subject to a holonomic constraint. We establish necessary optimality conditions in order to determine the minimizers of the fractional problems. The terminal point in the cost integral,as well as the terminal state, are considered to be free, and we obtain corresponding natural boundary conditions.

关键词： Fractional calculus fractional calculus of variations holonomic constraints isoperimetric constraints optimization variable fractional order

Immediate–Early(IE) gene regulation of cytomegalovirus:IE1-and pp71-mediated viral strategies against cellular defenses

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Virologica Sinica 2014年第6期29卷 343-352页

作者： Lilith torres Qiyi Tang Department of Microbiology Ponce Health Sciences UniversityPonce Research InstitutePoncePR 00716USA

Three crucial hurdles hinder studies on human cytomegalovirus(HCMV): strict species specificity, differences between in vivo and in vitro infection, and the complexity of gene regulation. Ever since the sequencing of the whole genome was first accomplished, functional studies on individual genes have been the mainstream in the CMV field. Gene regulation has therefore been elucidated in a more detailed fashion. However, viral gene regulation is largely controlled by both cellular and viral components. In other words, viral gene expression is determined by the virus–host interaction. Generally, cells respond to viral infection in a defensive pattern; at the same time, viruses try to counteract the cellular defense or else hide in the host(latency). Viruses evolve effective strategies against cellular defense in order to achieve replicative success. Whether or not they are successful, cellular defenses remain in the whole viral replication cycle: entry, immediate–early(IE) gene expression, early gene expression, DNA replication, late gene expression, and viral egress. Many viral strategies against cellular defense, and which occur in the immediate–early time of viral infection, have been documented. In this review, we will summarize the documented biological functions of IE1 and pp71 proteins, especially with regard to how they counteract cellular intrinsic defenses.

关键词： cytomegalovirus(CMV) major immediate early promoter(MIEP) IE1 pp71 nuclear domain 10(ND10) intrinsic cellular defense enhancer virus-host interaction

OsDMI3,a Ca^(2+)/calmodulin kinase,integrates and amplifies H_(2)O_(2) and Ca^(2+) signaling in ABA-mediated responses

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Molecular Plant 2023年第6期16卷 968-970页

作者： Miguel-Angel torres Diego Jose Berlanga Centro de Biotecnologia y Genomica de Plantas Universidad Politecnica de Madrid(UPM)-Instituto Nacional de Investigacion y Tecnologia Agraria y Alimentaria(INIA/CSIC)Campus de Montegancedo UPM28223 Pozuelo de AlarconMadridSpain Departamento de Biotecnologia-Biologia Vegetal Escuela Técnica Superior de Ingenieria AgronomicaAlimentaria y de BiosistemasUPM28040 MadridSpain

Abscisic acid(ABA)is an important hormone that regulates both plant development and stress responses(Chen et al.,2020).In the absence of ABA,group A PROTEIN PHOSPHATASE 2Cs(PP2Cs)interact with and inhibit SUCROSE-NON-FERMENTING 1-RELATED KINASES 2(SnRK2s).When ABA is present,ABA receptor PYRABACTIN RESISTANCE 1 and PYRABACTIN RESISTANCE 1-LIKE PROTEINS bind to and inhibit PP2Cs,allowing phosphorylation and activation of SnRK2s that,in turn,phosphorylate downstream targets,such as transcription factors,ion channels,and transporters(Figure 1).

关键词： SnRK2 Figure

Interpreting Morphologically Homogeneous(Paleo-)Populations as Ecological Species Enables Comparison of Living and Fossil Organism Groups,Exemplified by Nummulitid Foraminifera

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Journal of Earth Science 2022年第6期33卷 1362-1377页

作者： Johann Hohenegger Ana Ivis torres-Silva Wolfgang Eder Institute for Paleontology University of Vienna1090ViennaAustria

Morphologically homogeneous groups,either living populations or fossil paleo-populations,must be regarded as ecological species,independent of their molecular genetic resemblance in living *** is always expressed during development by structure genes initiated from a network of regulator genes acting at different times and intensities,additionally being subjected to epigenetic ***,homogeneous populations influenced by the environment represent species better than the reproduction(biological species)or molecular-genetic approach using ancestral sequences like *** and fossil representatives of nummulitid foraminifera were chosen to demonstrate complete reconstruction of morphology using metrical growth-invariant and growth-independent *** these characters,6 models were established to define ecological species in living and fossil ***,a distinction between evolutionary and environmental effects in fossil forms was possible using discriminant analysis showing characters that are responsible for differentiating between evolutionary and environmental trends.

关键词： ecological species growth-invariant metrical characters morphology homogeneity nummulitids

FAST SPECTRAL GALERKIN METHOD FOR LOGARITHMIC SINGULAR EQUATIONS ON A SEGMENT＊

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Journal of Computational Mathematics 2018年第1期36卷 128-158页

作者： Carlos Jerez-Hanckes Serge Nicaise Carolina Urzua-torres School of Engineering Pontificia Universidad Catolica de Chile 782-0436 Santiago Chile. LAMAV Universite de Valenciennes and CNRS 59313 Valenciennes France. Seminar for Applied Mathematics ETH Zurich Raemistrasse 101 8092 Zurich Switzerland.

We present a fast Galerkin spectral method to solve logarithmic singular equations on segments. The proposed method uses weighted first-kind Chebyshev polynomials. Conver- gence rates of several orders are obtained for fractional Sobolev spaces H^-1/2 （or H00^-l/2）. Main tools are the approximation properties of the discretization basis, the construction of a suitable Hilbert scale for weighted L2-spaces and local regularity estimates. Numerical experiments are provided to validate our claims,

关键词： Screen problems Boundary integral operators Spectral methods.

Hierarchical dispatch of multiple microgrids using nodal price:an approach from consensus and replicator dynamics

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Journal of Modern Power Systems and Clean Energy 2019年第6期7卷 1573-1584页

作者： Miguel A.VELASQUEZ Oscar torres-PEREZ Nicanor QUIJANO Angela CADENA Department of Electrical and Electronics Engineering Universidad de los AndesBogotaColombia

A hierarchical approach for the energy management of geographically close microgrids connected through a dedicated AC power network is proposed in this *** proposed approach consists of a two-layer energy management system(EMS)for networked *** the lower layer,each micro grid solves its own economic dispatch problem through a distributed model predictive control approach that respects capacity limits and ramp-rate constraints of distributed *** the upper layer,the energy trading in the network of microgrids decides how to optimally trade the energy based on the marginal cost information from the lower layer in order to improve global optimization objectives,e.g.,social *** order to solve the trading problem,a consensusbased algorithm and a replicator dynamics algorithm are proposed assuming that the marginal cost function of the microgrid is known and *** is shown that both algorithms converge to the same solution,which is equivalent to the minimization of operation *** consensus-based algorithm is extended in order to tackle more general marginal cost functions and trading network ***,the effect of ramp constraints and network limits is *** show the effectiveness of the proposed algorithms for three interconnected microgrids with different characteristics.

关键词： Consensus Economic dispatch Hierarchical control Networked microgrids Ramp limits Replicator dynamics

Sustainable Activated Carbons from Agricultural Residues Dedicated to Antibiotic Removal by Adsorption

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Chinese Journal of Chemical Engineering 2012年第3期20卷 524-529页

作者： Jonatan torres-Pérez Claire Gérente Yves Andrès Universidad Autónoma de Ciudad Juárez ICBDepartamento de Ciencias Químico-BiológicasCiudad JuárezChihuahuaMéxico L'UNAM Université Ecole des Mines de NantesCNRSGEPEAUMR 61444 rue Alfred KastlerBP 2072244 307 Nantes cedex 03France

The. *** this study are to convert at laboratory *** *** residues into activated carbons （AC） with specific properties, to characterize them and to test them in adsorption reactor for tetracycline removal, a common antibiotic. Two new ACs were produced by direct activation with steam from beet pulp （BP-H2O） and peanut hu_lls （PH-H2O） in environmental friendly conditions BP-H2O and PH-H2Opresentcarbon content rangedcarbons with different intrinsic properties.

关键词： activated carbon adsorption antibiotic characterisation waste valorisation water treatment

Constant-gain nonlinear adaptive observers revisited: an application to chemostat systems

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Frontiers of Information Technology & Electronic Engineering 2021年第1期22卷 68-78页

作者： Jorge A.torres Arno SONCK Sergej CELIKOVSKY Alma R.DOMINGUEZ Automatic Control Department CINVESTAVMexico City 07360Mexico The Czech Academy of Sciences Institute of Information Theory and AutomationPrague 18200Czech Republic Biotechnology and Bioengineering Department CINVESTAVMexico City 07360Mexico

This study deals with constant-gain adaptive observers for nonlinear systems,for which relatively few solutions are available for some particular *** introduce an asymptotic observer of constant gain for nonlinear systems that have linear *** allows the observer design to be formulated within the linear matrix inequality paradigm provided that a strictly positive real condition bet ween the inpu t disturbance and the output is *** proposed observer is t hen applied to a large class of nonlinear chemos tat dynamical systems that are widely used in the fermentation process,cell cultures,medicine,*** fact,under standard practical assumptions,the necessary change of the chemos tat state coordinates exis ts,allowing use of the const ant-gain ***,the developed theory is illustrated by estimating pollutant concentration in a Spirulina maxima wastewater treatment facility.

关键词： Nonlinear observers Adaptive observers Coordinate change Chemos tat Pollu taut observation