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Development of a Construction material for Indoor and Outdoor, metakaolinite-Based Geopolymer, with Environmental Properties

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材料科学与工程（中英文A版） 2019年第4期9卷 131-142页

作者： m.mondragón-figueroa Héctor.R.Guzmán-Carrillo miguelÁngel Rico JoséLuis.Reyez-Araiza Jorge.Pineda-Piñón Edgar J.López-naranjo maría C.Columba-Palomares Jóse.m.López-Romero Josè.Ramón Gasca-Tirado Alejandro.manzano-Ramírez CInVESTAV-Querétaro Libramiento Norponiente#2000Fraccionamiento Real de JuriquillaQuerétaro 76230Qro.México Facultad de Química Universidad Autónoma de Querétaro centro de estudios Académicos sobre contaminación AmbientalQuerétaro 76010Qro.México DIPFI Facultad de IngenieríaUniversidad Autónoma de QuerétaroC.U.Cerro de las CampanasCentroQuerétaro 76010Qro.México Instituto Politécnico nacional Centro de Investigación en Ciencia Aplicada y Tecnología AvanzadaUnidad QuerétaroCerro Blanco No.141Colinas del CimatarioQuerétaro76090Qro.México DIP-CUCEI Universidad de GuadalajaraJoséGuadalupe Zuno#48Los BelenesZapopan 45100Jal.México Facultad de Farmacia Universidad Autónoma del Estado de MorelosAv.Universidad#1001Cuernavaca 62209Mor.México Departamento de Ingeniería Universidad de GuanajuatoGuanajuato 36000México

Environmental problems that came from the human activity have many facets,since pollution of the atmosphere arises from vehicles,industrial emissions while pollution of water could be from organic compounds,pesticides *** can cause serious health effects,such as respiratory diseases,including asthma and lung ***,in the present work,a kinetic study on the effective adsorption and photo degradation of methylene blue(mB)dye,under ultraviolet A(UVA)irradiation of an alkali activated inorganic polymer(geopolymer)with homogeneously dispersed titanium dioxide(TiO2)micro-particles is *** addition,antimicrobial testing of the alkali activated TiO2 material was performed showing a bacteriostatic effect.

关键词： Heterogeneous photocatalysis semiconductor alkali activated bacteriostatic effect

Spatial Distribution of nymphs Populations Bactericera cockerelli Sulc in Tomato Crops(Physalis ixocarpa Brot)

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Phyton-International Journal of Experimental Botany 2019年第4期88卷 449-458页

作者： Roberto Rivera-martínez Agustín David Acosta-Guadarrama JoséFrancisco Ramírez-Dávila Fidel Lara Vazquez Dulce Karen figueroa figueroa Autonomous University of the State of mexico Cerrillo Piedras Blancas n/n km 15Toluca50200Mexico Laboratory of Entomology Research and Technology in Precision Farming UAEMCerrillo Piedras Blancas n/n km 15Toluca50200México

Tomato crops(Physalis ixocarpa Brot.)are produced in almost all mexico,part of the United States and Central *** the tomato production has suffered economic losses of 70%to 80%due the presence of yellowing and floral abortion,whose causal agent has been attributed to the presence of phytoplasma;an insect vector of these phytoplasma is Bactericera cockerrelli *** control of this psyllid has lacked effectiveness because their spatial distribution is unknown within tomato *** study aimed to determine the spatial distribution of populations of nymphs of *** in four tomato plots,the determination of the spatial distribution was performed by means of *** experimental semivariogram was determined to adjust to a theoretical model(spherical,exponential or Gaussian)through the program Variowin 2.2,the adjustment was validated with the method of cross-validation and aggregation maps of the pest were obtained through Kriging with Surfer 9.0 *** short-term time-space stability of the pest was determined through the tests Crámer-von *** results showed that populations of nymphs of *** have a distribution of aggregate type,which was corroborated by density *** are not present in 100%of the surface of the experimental plots,which helps to direct control measures on specific areas of infestation.

关键词： Geostatistics Bactericera cockerelli Sulc Kriging

Photosynthetic Regulation of the Cyanobacterium Synechocystis sp. PCC 6803 Thioredoxin System and Functional Analysis of TrxB （Trx x） and TrxQ （Trx y） Thioredoxins

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molecular Plant 2009年第2期2卷 270-283页

作者： m. Esther Perez-Perez Eugenio martin-figueroa Francisco J. Florencio Instituto de Bioquimica Vegetal y Fotosintesis Universidad de Sevilla-CSIC Avda Americo Vespucio 49 41092-Sevilla Spain

The expression of the genes encoding the ferredoxin-thioredoxin system including the ferredoxin-thioredoxin reductase （FTR） genes ftrC and ftrV and the four different thioredoxin genes trxA （m-type; sir0623）, trxB （x-type; sir1139）, trxC （sll1057） and trxQ （y-type; sir0233） of the cyanobacterium Synechocystis sp. PCC 6803 has been studied according to changes in the photosynthetic conditions. Experiments of light-dark transition indicate that the expression of all these genes except trxQ decreases in the dark in the absence of glucose in the growth medium. The use of two electron transport inhibitors, 3-（3,4-dichlorophenyl）-1,1-dimethylurea （DCmU） and 2,5-dibromo-3-methyl-6-isopropyl-p- benzoquinone （DBmIB）, reveals a differential effect on thioredoxin genes expression being trxC and trxQ almost unaffected, whereas trxA, trxB, and the ftr genes are down-regulated. In the presence of glucose, DCmU does not affect gene expression but DBmIB still does. Analysis of the single TrxB or TrxQ and the double TrxB TrxQ Synechocystis mutant strains reveal different functions for each of these thioredoxins under different growth conditions. Finally, a Synechocystis strain was generated containing a mutated version of TrxB （TrxBC34S）, which was used to identify the potential in-vivo targets of this thioredoxin by a proteomic analysis.

关键词： Cyanobacteria photosynthetic electron transport Synechocystis oxidative stress thioredoxin.

The unusual life history of a southern Iberian Peninsula population of Torleya major （Ephemeroptera： Ephemerellidae）

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Insect Science 2011年第5期18卷 583-589页

作者： m. J. Lopez-Rodriguez J. m. Tierno de figueroa J. Alba-Tercedor Departamento de Biologia Animal Facultad de Ciencias Universidad de Granada Granada Spain

The nymphal biology of a population of Torleya major （Klapalek） in southem Iberian Peninsula was studied. An atypical life cycle pattern is described, with eggs hatching in August producing a fast-developing cohort with adults emerging in autumn and a second slow-developing cohort with adults emerging in spring of the following year. nymphal growth occurred primarily in summer-autumn （in the first cohort） and in spring （in the second）. The origin of such a life history is discussed. nymphs were collector-gatherers, consuming mainly detritus. Although ontogenetic shifts on the use of trophic resources were detected, similar food was utilized during the months when both cohorts cohabited, eliminating the possibility that the rapid growth of the first cohort could be related to the utilization of different food resources.

关键词： collector-gatherer life cycle mayfly nymphal feeding southern Iberian Peninsula

Biodecoloration of Reactive Black 5 by the methylotrophic yeast Candida boidinii mm 4035

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Journal of Environmental Sciences 2017年第3期29卷 78-87页

作者： maria m.martorell Hipo1ito F.Pajot Pablo m.Ahmed Lucia I.C.de figueroa Antarctic Argentinian Institute Balcarce 290CABAArgentina PROImI-COnICET TucumánArgentina Department of Products Quality IV San Pablo University-TucumdnTucumánArgentina Agroindustrial Experimental Station Obispo Colombres TucumánArgentina Department of Superior microbiology Faculty of BiochemistryChemistry and PharmacyNational University of TucumánTucumánArgentina

Azo dyes are extensively used in textile dyeing and other industries. Effluents of dying industries are specially colored and could cause severe damage to the environment. The anaerobic treatment of textile dying effluents is nowadays the preferred option, but it could generate carcinogenic aromatic amines. Recently, yeasts have become a promising altemative, combining unicellular growth with oxidative mechanisms. This work reports the characterization of the first methylotrophic yeast with dye decolorizing ability, Candida boidinii mm 4035 and some insights into its decoloration mechanism. The analysis of two selected media revealed a possible two stages mechanism of Reactive Black 5 decoloration. In glucose poor media, decoloration is incomplete and only the first stage proceeds, leading to the accumulation of a purple compound. In media with higher glucose concentrations, the yeast is able to decolorize totally an initial concentration of 200 mg/L. The entire process is co-metabolic, being largely dependent on glucose concentration but being able to proceed with several nitrogen sources. manganese dependent peroxidase but not laccase activity could be detected during decoloration. Aromatic amines do not accumulate in culture media, supporting an oxidative decoloration mechanism of unknown ecophysiological relevance.

关键词： Biodecoloration Dyesmethylotrophic yeasts medium optimization

Reproductive performance of the mesa silverside(Chirostoma 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： JOSÉLUIS ARREDOnDO-figueroa LAURA GEORGInA nÚÑEZ-GARCÍA PALOmA ADRIAnA HEREDIA-GUZmÁn JESÚS T.POnCE-PALAFOX Posta 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 Estudios Superiores Iztacala Universidad Nacional Autónoma de MéxicoEstado de MéxicoMéxico Centro de Innovación y Transferencia Tecnológica CEnITT Posgrado CBAPEscuela Nacional de Ingeniería PesqueraUniversidad Autónoma de NayaritTepicNayaritMéxico

Chirostoma jordani is a native annual species inhabiting lacustrine waters of the Central mexico *** is widely distributed and is currently facing high environmental *** experi-ments were performed to study the reproductive performance of this *** of the experiments were conducted in 270-L indoor recirculation *** males and one female at the first stage of reproduction were included in each test.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 spawns,fertilised eggs and 30-day-old juveniles were counted and the survival rate was *** results indicated significant differences(Pn *** spawn numbers and greater egg production were observed under controlled photoperiod,and higher numbers of juveniles and a higher survival rate were observed under natural *** trials exhibited different patterns of egg produc-tion during the *** egg production in the natural-photoperiod trials followed a polynomial curve *** contrast,the trials under the controlled photoperiod showed an irregular pattern of increases and decreases in egg production.

关键词： breeding Atherinopsidae eggs juveniles survival rate

Synthesis and characterization of bulk composite Fe-Si-B alloys with small concentration of nb and mo

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Acta metallurgica Sinica(English Letters) 2010年第6期23卷 401-408页

作者： S.Bez I.Betancourt I.A.figueroa Institute for materials Research National Autonomous University of Mexico (UNAM)

The preparation and some mechanical, thermal and magnetic properties of the as cast bulk composite ***4 （m=nb, mo） alloys obtained by suction casting are presented and discussed. The microstructrural results showed the existence of a crystalline a-Fe（Si） phase embedded in a glassy matrix. The values of microhardness （/Iv） and yield strength （ay） for the nb-containing alloy are exceptionally high, i.e. （12.65~0.3） GPa and （4.22~0.10） GPa, respectively. The saturation polarization values are found to be as high as 1.24 T for both composite ~11oys. It is thought that the interplay between the secondary crystalline phases and amorphous matrix could be responsible for the mechanical and magnetic behaviour of these alloys.

关键词： Bulk composite alloys magnetic properties mechanical proper- ties Thermal stability and suction casting

Hardness-Lattice Parameter Correlation for Aged Al-Zn-mg Alloys

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Journal of materials Science & Technology 2010年第12期26卷 1083-1088页

作者： P.Fernandez G.Gonzalez I.Alfonso I.A.figueroa Instituto de Investigaciones 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 close to 2.5 were produced by conventional ingot casting metallurgy. The ingots were solution heat treated at 500℃ for 0.5 h and aged at 180℃ for times between 0.5 and 80 h. The structural characterization was carried out by X-ray diffraction （XRD）, transmission electron microscopy （TEm）, selected area electron diffraction （SAED） and Vickers mierohardness measurements （HV）. The study was focused on the investigation of the precipitates formation and the relationship between hardness and lattice parameter for α-Al. The results showed that there was an inverse correlation for all the experimental conditions, and the aged peaks coincided with lattice parameter minima. Significant precipitates formation only occurred for the alloy containing 5.5 wt pct Zn and 2.1 wt pct mg, provoking an important strengthening and variations in the lattice parameter, however, this was not observed for the alloy containing 2.2 wt pct Zn and 0.95 wt pct mg. A plausible explanation of the increment of hardness values could be the presence of a well distributed η phase （mgZn2）. At initial stages of the precipitation process, η′ was the most abundant precipitate while the phase τ- was observed at overaged conditions. These results showed that the aging response of the conventionally cast Al-Zn-mg alloys could be obtained using the lattice parameter of the α-Al matrix, even for alloy systems with low precipitates formation.

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

The Study on the Flow Generated by an Array of Four Flettner Rotors: Theory and Experiment

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Applied mathematics 2017年第12期8卷 1851-1858页

作者： Fernando Garzón Aldo figueroa Instituto de Investigación en Ciencias Básicas y Aplicadas Universidad Autónoma del Estado de Morelos Cuernavaca México COnACYT-Centro de Investigación en Ciencias Universidad Autónoma del Estado de Morelos Cuernavaca México

We present an immersed array of four rotors whose promoted flow can be mathematically modeled with a creeping flow solution from the incompressible navier-Stokes equations. We show that this solution is indeed representative of the two-dimensional experiment and validate such class of solution with experimental data obtained through the Particle Image Velocimetry technique and time-lapsed particles visualizations.

关键词： Fluid mechanics Flettner Rotor Fundamental Solutions