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Optics and Photonics Journal 2013年第2期3卷 1-12页

作者： José Escorcia-García Miguel Eduardo Mora-Ramos centro de investigación en Energía Universidad Nacional Autónoma de México Temixco Morelos México Física Teórica y aplicada Escuela de Ingeniería de Antioquia Sede Las Palmas Envigado Antioquia Colombia

Selective spatial confinement of the electric field intensity is theoretically obtained for the light propagation along hybrid structures conformed by periodic and Fibonacci quasiperiodic dielectric multilayers. Sandwich-like configurations featuring periodic-quasiperiodic-periodic as well as quasiperiodic-periodic-quasiperiodic designs exhibit spatial localization of a large percent of the optical signal within specific zones of the hybrid system. Such a feature might be of interest in the pursuing of lasing devices based on porous silicon. It is found that the electric field confinement does not only depend on the quality of the defect or a particular transmission mode observed in the reflectivity spectra. We show that it is possible to enhance the electric field confinement solely varying the angle of incidence. The possibility of realizing finite photonic crystals with reduced size and very well defined band gap by means of a quasiperiodic-periodic-quasiperiodic hybrid multilayer is also revealed.

关键词： Optical Properties Electric Field Multilayers Hybrid Structures

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

In Vitro-Propagation of Agave tequilana Weber *** in a Temporary Immersion System

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Phyton-International Journal of Experimental Botany 2022年第1期91卷 83-96页

作者： Otilio Vázquez-Martínez Héctor Gordon núñez-Palenius Eugenio M.Pérez-Molphe Balch Mauricio Valencia-Posadas Luis Pérez-Moreno Graciela M.L.Ruiz-Aguilar M.Gómez-Lim División de ciencias de la Vida Universidad de GuanajuatoIrapuato36500México departamento de Química Centro de Ciencias BásicasUniversidad Autónoma de AguascalientesAguascalientes20131México departamento de ingeniería Genética CINVESTAV Unidad IrapuatoIrapuato36500México

In Mexico,there is a need to produce large quantities of plantlets for the establishment and replanting of blue(***)agave production *** of these plots are within the origin denomination area(DOT,Spanish acronym)of the distilled product of this plant,known as *** objective of this study was to develop an in vitropropagation protocol for Agave tequilana Weber *** using segmented stems in both:solid and liquid media.A disinfection and in vitro technique were developed to obtain shoots,through plantlets collected in commercial plots,which attained 100%surface-disinfection and budding *** the multiplication stage,the effects of 6-Benzylaminopurine(BA)(0.0,4.4 and 13.2μM)and kinetin(0.0,9.4,18.8 and 37.6μM)were evaluated on lateralshoot production of segmented sagittal *** were cultivated on Murashige&Skoog(MS)medium,with the addition of 3.0%sucrose and 8 g L−1 *** was observed that BA and kinetin increased the number of shoots per explant,obtaining up to 18 and 26,***,it was found that just the sagittal segmentation of explants increased axillary *** the other hand,segmented-stem bases were grown in MS liquid medium with 3.0%sucrose,inside a RITAsystem,programmed by a 5 min immersion step with a frequency of every 4 *** effect of Indole−3-Acetic acid(IAA)(0.57,2.9,5.7μM)was evaluated,while maintaining a concentration of BA(13.2μM).It was observed that the greatest concentration of IAA led to the formation of more than 20 buds per *** results offer a new methodology to increase the efficiency of *** Weber ***-in vitro multiplication by sagittal segmentation of stems and the addition of BA and/or IAA.

关键词： Plant tissue culture stem-disk culture tequila in vitro culture

Ustilago maydis, a delicacy of the Aztec Cuisine and a Model for Research

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natural Resources 2014年第6期5卷 256-267页

作者： Claudia G. León-Ramírez José Alejandro Sánchez-Arreguín José Ruiz-Herrera departamento de ingeniería Genética Unidad Irapuato Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional Irapuato Gto México

Ustilago maydis is the causal agent of the disease known as corn smut or Huitlacohe;their natural hosts are maize (Zea mays L.) and its putative ancestor teocintle (Zea mays ssp. parviglumis and ssp. mexicana). In México there is an evidence of its use as human food since pre-hispanic times. Huitlacoche is a typical Mexican food with interesting nutritional properties and distinctive flavor. Its use in cuisine is considered as a culinary delicacy in Mexico and several parts of the world and the current consumption is increasing markedly, mainly due to its exclusive flavor different from any other known food. Huitlacoche contains proteins, carbohydrates, fats, minerals and vitamins that contribute to its nutritional value, also it has been reported that it contains proteins with balanced levels of essential amino acids, something which does not occur in corn having a deficiency mostly in lysine. The fungus also contains compounds with antioxidant properties, consequently it can be included in what are now known as nutraceutical foods. Besides its use in the food, this fungus has been used in different kinds of basic investigation, such as DnA recombination, signaling, cell biology, biotrophic plant-pathogen interactions and others. Its characteristics of dimorphism, and the detailed knowledge we have on its pathogenic development, that we describe in detail, make it an ideal subject for the analysis of fungal differentiation, and for the knowledge of the behavior of the highly aggressive plant pathogens that are members of its taxonomic group, the Ustilaginales. In the present communication we make a thorough review of the nutritional characteristics of U. maydis, its life cycle, and the molecular bases of its differentiation, morpohogenesis and pathogenicity.

关键词： Ustilago maydis Huitlacoche nutraceutical Basidiocarps Virulence

Biocomposites Based on Thermoplastic Starch and Granite Sand Quarry Waste

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Journal of Renewable Materials 2019年第4期7卷 393-402页

作者： María G.Passaretti Mario D.ninago Cecilia I.Paulo Horacio A.Petit Edgardo F.Irassarc Daniel A.Vega Marcelo A.Villar Olivia V.López Planta Piloto de ingeniería Química PLAPIQUI(UNS-CONICET)Camino"La Carrindanga"Km 7Bahía Blanca8000Buenos AiresArgentina departamento de ingeniería Química Universidad Nacional del Sur(UNS)Bahía Blanca8000Buenos AiresArgentina Facultad de ciencias aplicadas a la Industria(FCAI) Universidad Nacional de Cuyo(UNCuyo)Bernardo de Irigoyen 375San Rafael5600MendozaArgentina Consejo nacional de investigaciones Científicas y Técnicas(COnICET) Godoy Cruz 2290Ciudad Autónoma de Buenos AiresC1425FQBBuenos AiresArgentina Facultad de ingeniería Universidad Nacional del Centro de la Provincia de Buenos Aires(UNCPBA).Centro de Investigaciones en Física e IngenieríaCIFICEN(UNCPBA-CICPBA-CONICET)7400OlavarríaArgentina Instituto de Física del Sur IFISUR(UNS-CONICET)Bahía Blanca8000Argentina

Granite stone is a by-product of the rock crushing *** industrial waste in powder form that causes health problems and environmental *** particles fraction can be used as a partial replacement of sand in concrete *** this work,an alternative exploitation of this waste fraction is *** sand(GS)with particles mean size of ~1μm was employed as thermoplastic starch(TPS)filler at different *** were obtained by melt-mixing and thermo-compression,achieving translucent and easy to handle films.A good GS dispersion within the matrix was evidenced by *** presence induced a shift of starch’s melting point to higher values and a better thermal *** UV absorption capacity was increased ~90% by GS *** increment in TPS young’s modulus and maximum tensile stress of 5 and 3 times,respectively was observed by adding 5%w/w GS.

关键词： Thermoplastic starch granite sand melt processing final properties

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

Removal of Basic Blue 9 Dye by Hydrogen Peroxide Activated by Electrogenerated Fe2+/Fe3+and Simultaneous Production of Hydrogen

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Journal of Environmental Protection 2015年第8期6卷 781-791页

作者： yaneth Bustos-Terrones María neftalí Rojas-Valencia Alberto álvarez-Gallegos Patricía García División de Estudios de Posgrado e investigación-ingeniería Ambiental Instituto Tecnológico de Culiacán Culiacán México Coordinación de ingeniería Ambiental Instituto de Ingeniería Universidad Nacional Autónoma de México México D. F. México centro de investigación en ingeniería y ciencias aplicadas (CIICAp) Universidad Autónoma del Estado de Morelos Cuernavaca México

Electrochemical techniques were used to oxidize organic pollutants by Fenton process using a mix of H2O2 and ferrous ions at a parallel plate reactor. The first stage was to build a micro scale reactor comprising two compartments, cathode and anode, separated by a membrane (nafion-117). Each compartment has inlets and outlets to allow the flow of fluids (10 Lmin-1). The function of the reactor is to oxidize organic pollutants as well as to produce H2. Hydrogen is electrogenerated in the catholyte by the reduction of protons on a carbon steel cathode in acidic medium (0.05 M H2SO4). At the same time, a mixture of Fe2+/Fe3+ ions is produced in the anolyte (0.05 M na2SO4, pH ≈ 2) by means of the oxidation of a sacrificial electrode made of stainless steel mesh. Fe2+/Fe3+ ions interact with H2O2 to generate strong oxidants which are responsible for oxidizing the organic matter and removing color. A voltage of 1 V was applied between the electrodes and remained constant, while the current observed was approximately 0.06 A. Under these conditions, the activation rate with different H2O2 concentrations (15, 20, 25, 30, 35, 40, 45 and 50 mM) was evaluated. The maximum activation rate (1.3 mM·min-1) was obtained using 30 mM H2O2. Under these conditions, the oxidation of a synthetic industrial effluent (0.615 mM BB9) was performed and the following results were obtained: 95% of this concentration was removed in 5 minutes and 15 mL of H2 was electrogenerated in 30 minutes.

关键词： BB9 degradation Fenton Process Hydrogen Peroxide Hydrogen Production

Analysis of the Performance of a dehulling System for Confectionary Sunflower Seeds

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Food and nutrition Sciences 2014年第6期5卷 541-548页

作者： Ana Karina de Figueiredo Luciana Marcela Rodríguez Isabel Concepción Riccobene Susana Maria nolasco Facultad de ingeniería Universidad Nacional del Centro de la Provincia de Buenos Aires Grupo de Investigación TECSE Departamento de Ingeniería Química Buenos Aires Argentina

Confectionary sunflower, which has a larger size and lower oil content than oilseed sunflower, has a considerable market, since it is used for birdfeed and human consumption. The characteristics of use of confectionary sunflower seeds require a dehulling process that is efficient in the removal of the hull and that also allows obtaining a product consisting mainly of whole kernels. Response surface methodology was used to determine an optimal combination of working conditions in the dehulling process of confectionary sunflower seeds. Optimization factors were impact speed, expressed in terms of the peripheral speed (28.3 -41.9 m/s), and moisture content of the seeds (4% -14%, dry basis—db). A central composite rotatable design (CCRD) was used to develop models for the responses (dehulling ability—DA and percentage of whole kernels—WK). Applying the desirability function method, the optimal values of the factors were determined using maximum WK and maximum DA as criteria. The results of the optimization technique suggest that by dehulling Mycogen 9338 confectionary sunflower seeds at 12.3% db and 32.5 m/s, the maximum values of DA and WK (72.6% and 63%, respectively) would be obtained. The moisture value defined as optimal determines a requirement of humidification of the seeds prior to dehulling, establishing the need for a technical and economic feasibility study.

关键词： Confectionary Sunflower dehulling Response Surface Methodology Whole Kernels

Temperature-Programmed Reduction and Dispersive X-Ray Absorption Spectroscopy Studies of CeO2-Based nanopowders for Intermediate-Temperature Solid-Oxide Fuel Cell Anodes

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Materials Sciences and Applications 2019年第10期10卷 631-642页

作者： Marina S. Bellora Joaquí n Sacanell Cristiá n Huck-Iriart Analí a L. Soldati Susana A. Larrondo Diego G. Lamas COnICET/Laboratorio de Cristalografía aplicada Escuela de Ciencia y Tecnología Universidad Nacional de General San Martín San Martín Argentina departamento de Física de la Materia Condensada Gerencia de Investigación y Aplicaciones Centro Atómico Constituyentes Comisión Nacional de Energía Atómica San Martín Argentina Instituto de nanociencia y nanotecnología (Inn) CNEA-CONICET San Martín and San Carlos de Bariloche Argentina UnIdeF-COnICET-MIndeF Departamento de Investigaciones en Sólidos CITEDEF Villa Martelli Argentina Instituto de investigación e ingeniería Ambiental Universidad Nacional de General San Martín San Martín Argentina

In this work, we study the influence of the average crystallite size and dopant oxide on the reducibility of CeO2-based nanomaterials. Samples were prepared from commercial Gd2O3-, Sm2O3- and y2O3-doped CeO2 powders by calcination at different temperatures ranging between 400°C and 900°C and characterized by X-ray powder diffraction, transmission electron microscopy and BET specific surface area. The reducibility of the samples was analyzed by temperature-programmed reduction and in situ dispersive X-ray absorption spectroscopy techniques. Our results clearly demonstrate that samples treated at lower temperatures, of smallest average crystallite size and highest specific surface areas, exhibit the best performance, while Gd2O3-doped ceria materials display higher reducibility than Sm2O3- and y2O3-doped CeO2.

关键词： Crystallite Size CeO2-Based nanomaterials Sm2O3

Green Synthesis of Bimetallic nanoparticles From Prosopis juliflora(Sw)DC.,and Its Effect Against Cotton Mealybug,Phenacoccus solenopsis(Hemiptera:Pseudococcidae)

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Phyton-International Journal of Experimental Botany 2019年第3期88卷 269-275页

作者： V.Mendez-Trujillo B.Valdez-Salas M.Carrillo-Beltran M.A.Curiel-Alvarez O.Tzintzun-Camacho C.Ceceña-Duran D.Gonzalez-Mendoza Facultad de Medicina de la Universidad Autónoma de Baja California Dr.Humberto Torres Sanginés S/NCentro Cívico21000MexicaliBaja CaliforniaMéxico Instituto de ingeniería de la Universidad Autónoma de Baja California Calle de la Normal S/N y Boulevard Benito Juárez21100MexicaliBaja CaliforniaMéxico Instituto de ciencias Agrícolas de la Universidad Autónoma de Baja California(ICA-UABC).Carretera a delta S/n C.P.21705 Ejido Nuevo LeónBaja CaliforniaMéxico

Phenacoccus solenopsis has been recognized as an aggressively invasive species on cotton plants in different *** study was conducted to investigate the effect of green synthesized Cu/Zn-nanoparticles using aqueous leaf extract of Prosopis juliflora(mezquite)against *** scanning electron microscope(SEM)showed bimetallic nanoparticles of Cu/Zn-nPs with spherical shape with varying size of 74.33 nm to 59.46 *** than 30%mortality of *** was observed with Cu/Zn-nanoparticles(100 ppm)at 96 hours after *** mortality of *** was recorded with Cu/Zn solution(100 ppm)and aqueous *** *** results of the viability test for Cu/Zn-nanoparticles of *** showed a significant reduction of the cell viability by 50%in insect exposed to Cu/*** studies about nanotoxicity of Cu/Zn-nPs of *** are needed to reveal the mechanism of toxicity this phytonanoparticles in ***.

关键词： Photosynthesis biocontrol cotton mealybug nanoinsecticide