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La modernización con caracteristicas chinas

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今日中国（西文版） 2024年第3期 40-41页

作者： MILTON reyes HERRERA 不详

Nucleation and growth kinetics of La0.7Sr0.3Cr0.4Mn0.6O3-δ SOFC perovskite:Symmetry alteration evolution induced by Cu2+ and Ni2+ impregnation

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Progress in Natural Science:Materials International 2016年第6期26卷 665-670页

作者： A.Concha-Balderrama G.Rojas-George J.Alvarado-Flores H.Esparza-Ponce M.H.Bocanegra-Bernal A.reyes-Rojas Centro de Investigación en Materiales Avanzados S.C.(CIMAV) Laboratorio Nacional de NanotecnologíaMiguel de Cervantes 120 Complejo Industrial ChihuahuaCd.de Chihuahua

La0.7Sr0.3Cr0.4Mn0.6O3-δperovskite nanoparticles have been synthetized using an ethylene glycol modified solgel method and impregnated by Cu0.75Ni0.25nanoparticles. The phase transitions and nucleation kinetics were studied by time resolved x-ray diffraction, Rietveld, Raman spectroscopy and high resolution transmission electron microscopy. Findings have shown that, an atomic disorder dominates from room temperature to 400 °C. Nanoparticles with crystal size < 26 nm start through nuclei formation of La0.7Sr0.3Cr0.4Mn0.6O3-δand SrCrO4solid solutions with Pm3m cubic and P21/n monoclinic symmetry respectively in the range of 600–650 °C. Symmetry reduction from the Pm3m→R3c space group had been obtained at a lower temperature（750 °C） than those reported in the literature in oxygen atmosphere and it was confirmed by an octahedral distortion, which takes place in the crystallographic direction[221]/（122）. The Johnson-Mehl-Avrami model had described the whole process, where the existence of two phases was shown before it reached its complete D3d6point group symmetry.

关键词： Perovskite structure Sol-gel method Composite Kinetics Rietveld

An Investigation on Biodiversity Perceptions of Students Enrolled in Ecotourism at De La Salle-College of Saint Benilde

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Journal of Agricultural Science and Technology(A) 2012年第11期2卷 1245-1252页

作者： Benigno Glenn reyes Ricaforte School of Hotel Restaurant and Institution Management De La Salle-College of Saint Benilde Manila 1004 Philippines

As an important component of ecotourism, it is imperative to investigate students＇ constructions of biodiversity-related concepts such as classification and variation in living things and ecosystem elements, identify the conceptual framework of biodiversity in relation to ecotourism, and determine its educational implications. The study population consisted of 13 students enrolled in ecotourism class section hotel AH （HAH） for first term, school year 2010-2011. Questionnaires were administered and focus-group discussions were conducted. Students＇ constructions of biodiversity concepts were determined using modified Conceptual Understanding of the Living Things and Classification （CULC） test. The conceptual framework of biodiversity in relation to ecotourism was investigated using a free word association test. Results were presented and discussed through qualifying themes in biology and biodiversity. Although biodiversity is a multidimensional concept, the questions focused only on ecosystem and species diversity. Analysis of the free association test demonstrated that participants have a very basic and incomplete conceptual understanding of biodiversity in the context of sustainable development and ecotourism. This study may lead to the review and improvement of ecotourism and ecology courses at the De La Salle-College of Saint Benilde （DLS-CSB）.

关键词： Biodiversity ecotourism ecosystem sustainable development investigation.

Asphaltene Surface Erosion in Air Plasma

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Plasma Science and Technology 2010年第1期12卷 81-86页

作者： M. VILLA M. CALIXTO-RODRIGUEZ H. MARTINEZ J. C. POVEDA P. G. reyes P. ALTUZAR Faculty of Sciences Autonomous University of the State of Mexico State of Mexico Mexico Institute of Physical Sciences Autonomous National University of Mexico 62210 Cuernavaca Morelos Mexico Energy Research Center Autonomous National University of Mexico 62580 Temixco Morelos Mexico

Optical emission spectroscopy was applied for plasma characterization during erosion of substrates of asphaltene. The amount of 100 mg of asphaltene was carefully applied to an electrode and exposed to air plasma glow discharge at a pressure of 1.0 Tort. The plasma was generated in a stainless steel discharge chamber by an AC generator with a frequency of 60 Hz and an output power of about 60 W. The electron temperature was found to be 6.88 eV, and the ion density is about 3.5×10^16 cm^-3. As the asphaltene was exposed to the air plasma, the surface was etched. The emission from molecular bands CS2,O3, N2^＋, NO, O2, CS, S2, CN, C7H7, C2, H2, C2^-, NiO, N2 and SO, and atomic line O, were observed and some of them were used to monitor the evolution of asphaltene erosion. The asphaltene weight was reduced gradually with an etching rate of about 0.844 mg/min, during the first 20 min.

关键词： optical emission spectroscopy asphaltene erosion

Estimation of age and growth and mortality parameters of the sea cucumber Isostichopus fuscus (Ludwig, 1875) and implications for the management of its fishery in the Galapagos Marine Reserve

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Aquaculture and Fisheries 2020年第5期5卷 245-252页

作者： Jorge Ramírez-González Nicolas Moity Solange Andrade-Vera Harry reyes Mackliff Charles Darwin Research Station Charles Darwin Foundation.Av.Charles DarwinPuerto AyoraGalapagosEcuador Galapagos National Park Directorate Marine Resources Department.Av.Charles DarwinPuerto AyoraGalapagosEcuador

The fishery of the sea cucumber Isostichopus fuscus was the most important one in the early 2000s in the Galapagos Marine *** overexploitation leads to its total closure from 2016 to *** the end of this period,if the co-management system of the Galapagos Marine Reserve decides to open this fishery,a total allowed catch must be established using the methodology of Wolff,Schuhbauer,and Castrejón(2012).The objective of this paper is to evaluate this methodology and improve the total allowed catch *** replicated Wolff et al.‘s methodology that uses the Cadima equation of Maximum Sustainable Yield(in Troadec,1977).We determined the age and growth parameters of *** to estimate total mortality and improved the calculation of the area of fishing and habitat of this species in Galapagos to estimate its *** found inconsistences in Wolff et al.‘s estimations of mortality and abundance and we recommend that the Maximum Sustainable Yield be used not as the total allowed catch,but as a limit reference point for this *** propose,instead,to use a dynamic abundance model that is capable of estimating a variety of reference points,including the fishing mortality for optimal fishing that is recommended to use to establish a total allowed *** addition,for the first time,the age and growth parameters of *** for Galapagos and the eastern-central region of the Pacific Ocean are determined(L∞=42.5 cm;K=0.21/year).

关键词： Sea cucumber Small-scale fishery Galapagos Marine Reserve Age&growth Mortality Maximum sustainable yield Total allowed catch

A comparison of process performance during the anaerobic mono-and co-digestion of slaughterhouse waste through different operational modes

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Journal of Environmental Sciences 2018年第2期30卷 149-156页

作者： Jhosané Pagés-Díaz Ileana Pereda-reyes Jose Luis Sanz Magnus Lundin Mohammad J.Taherzadeh Ilona Sárvári Horváth Process Engineering Centre (CIPRO) Universidad Tecnológica de La Habana "José Antonio Echeverría" (Technical University of Havana "José A. Echeverría") (Cujae) Swedish Centre for Resource Recovery University of Bor?s Department of Molecular Biology Autonomous University of Madrid

The use of consecutive feeding was applied to investigate the response of the microbial biomass to a second addition of substrates in terms of biodegradation using batch tests as a promising alternative to predict the behavior of the process. Anaerobic digestion（AD） of the slaughterhouse waste（SB） and its co-digestion with manure（M）, various crops（VC）, and municipal solid waste were evaluated. The results were then correlated to previous findings obtained by the authors for similar mixtures in batch and semi-continuous operation modes. AD of the SB failed showing total inhibition after a second feeding. Co-digestion of the SB ＋ M showed a significant improvement for all of the response variables investigated after the second feeding, while co-digestion of the SB ＋ VC resulted in a decline in all of these response variables. Similar patterns were previously detected, during both the batch and the semi-continuous modes.

关键词： Co-digestion Biomethane potential test Second feeding Specific methanogenic activity Slaughterhouse waste

Effect of the Density of Molten Metal on the Raining Phenomenon in Horizontal Centrifugal Casting

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Open Journal of Applied Sciences 2024年第7期14卷 1918-1926页

作者： Miguel A. Barron Joan reyes Departamento de Materiales Universidad Autonoma Metropolitana Azcapotzalco Ciudad de Mexico Mexico

In this work the influence of the density of the molten metal on the emergence of the raining phenomenon in the horizontal centrifugal casting process is numerically studied. Transient 2D numerical simulations were carried out using Computational Fluid Dynamics software. Three molten metals with different density, namely aluminum, iron and lead, and three angular frequencies, namely 50, 66 and 77 rad/s were considered. It is found that the density of the molten metal significantly affects the emergence, transient or permanent, of the rain phenomenon. However, the magnitude and duration of the rain phenomenon depend on the angular frequency of the rotating mold. Likewise, since gravitational forces affect the metal according to its density, the value of the critical rotation speed of the mold is also affected.

关键词： Angular Frequency Centrifugal Force Computational Fluid Dynamics Critical Rotation Speed G Factor Horizontal Centrifugal Casting Molten Metal Density

Avian-power line interactions in the Gobi Desert of Mongolia:are mitigation actions effective?

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Avian Research 2021年第3期12卷 382-390页

作者： Adrian Orihuela-Torres Juan MPérez-García Zebensui Morales-reyes Lara Naves-Alegre JoséASánchez-Zapata Esther Sebastián-González Área de Ecología Departamento de Biología AplicadaUniversidad Miguel Hernández de ElcheAvda.Universidad s/n03202 ElcheAlicanteSpain Departamento de Ecología Universidad de AlicanteCtra.San Vicente del Raspeig s/n03690 San Vicente del RaspeigAlicanteSpain

Background:Electrocution and collisions on power lines are among the leading causes of non-natural mortality for *** lines are exponentially increasing,particularly in developing countries,but mitigation strategies to prevent bird mortality are *** combines a recently increased power line network,an abundant raptor population,a dangerous crossarm configuration and a habitat with no natural perches,producing many bird-power line *** aim is to assess the bird mortality caused by power lines in the Gobi Desert of Mongolia,to determine the factors increasing the risk of bird electrocution,and to evaluate the effectiveness of used retrofitting ***:In July 2019 we covered 132.9 km of 15 kV power lines checking 1092 *** also conducted bird tran-sects to record raptor and corvid richness and abundance,to assess species vulnerability to ***:We recorded 76 electrocuted birds of 7 *** rate was 6.96 birds/100 *** most affected species were Common Raven(Corvus corax)and Upland Buzzard(Buteo hemilasius),highlighting the electro-cution of 5 endangered Saker Falcons(Falco cherrug).By contrast,we only recorded 8 individuals of 5 species collid-ing with wires,the most affected being Pallas’s Sandgrouse(Syrrhaptes paradoxus).About 76.1%of sampled poles had some mitigation *** these,96.6%were brush perch deflectors and 3.4%rotating-mirrors perch *** found differences in electrocution rates among crossarm configurations,with the strain insulator with one jumper being the most ***,we found no correlation between bird abundance and electrocution rates,suggesting that some species are more sensitive to *** no differences in total bird electrocu-tion rates were detected between poles with and without perch deterrents,when bird size is considered,deterrents reduced the mortality rate of small birds,while they were ineffective for medium-sized

关键词： Collision Crossarm configuration Electrocution Electric infrastructures Perch deterrent Power line network Raptor

Conifer establishment after the eruption of the Paricutin volcano in central Mexico

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Forest Ecosystems 2022年第1期9卷 71-82页

作者： Jesús Eduardo Sáenz-Ceja Blanca Lizeth Sáenz-Ceja J.Trinidad Sáenz-reyes Diego Rafael Pérez-Salicrup Instituto de Investigaciones en Ecosistemas y Sustentabilidad Universidad Nacional Autéonoma de MéxicoAntigua Carretera a Patzcuaro 8701 Col.Ex hacienda San Joséde la Huerta58190MoreliaMexico Escuela Nacional de Estudios Superiores Unidad Morelia Universidad Nacional Autónoma de MéxicoAntigua Carretera a Patzcuaro 8701 Col.Ex hacienda San Joséde la Huerta58190MoreliaMexico Instituto Nacional de Investigaciones Forestales Agrícolas y PecuariasCampo Experimental UruapanAv.Latinoamericana 1101Col.Revolución60500UruapanMexico

Background:Volcanic eruptions have large effects on forest ecosystems and create new substrates,triggering primary succession *** Paricutín volcano,born in central-western Mexico,erupted between 1943 and *** the cessation of the eruptive activity,plant colonization began on the lava flows and tephra deposits,including the conifer species that dominate the surrounding mature *** study aims to reconstruct the history of the establishment of conifer trees on the substrates created by the Paricutín ***:16 sampling plots were established along three transects with northern,southern,and south-western aspects,located every 250 m from the preserved forest to the volcanic *** cores from 400 conifer trees were extracted and their age was determined by cross-dating annual tree *** order of the species colonization and the tree establishment,abundance,and dominance patterns were ***,the influence of the distance from the mature forests and the inter-annual climatic conditions on the temporal tree establishment pattern was ***:Eight pine and one fir species have been established since 1970,only 18 years after the end of the eruptive ***,tree establishment increased by 12.9%annually after 1995,with the youngest tree in our sample getting established in *** did not find a well-defined temporal and spatial pattern of species arrival,which suggests that colonization occurred randomly,although the four pine species that were established early became the most abundant and *** establishment was not influenced by the distance from the mature forest,and wet inter-annual conditions did not enhance pulses of tree recruitment,exhibiting a continuous tree establishment ***:Conifer species have shown a great capacity for colonizing volcanic substrates created by the Paricutín eruption,which suggests that tropical montane conifers can regenerate rapidly under high-magni

关键词： Age structure Dendrochronology Lava flow Primary succession Tropical montane forest