Produção Nacional
Revisado por pares
Thais C. A. da Silva, Leonardo Marchiori, Bianca Oliveira Mattos, Sajjad Ullah, Hernane da Silva Barud, Rafael R. Domeneguetti, Hernán Dario Rojas-Mantilla, María Valnice Boldrin Zanoni, Ubirajara Pereira Rodrigues Filho, Elias P. Ferreira-Neto, Sidney J. L. Ribeiro,
This study explores the use of silica-coated bacterial nanocellulose (BC) scaffolds with bulk macroscopic yet nanometric internal pores/structures as functional supports for high surface area titania aerogel photocatalysts to design flexible, self-standing, porous, and recyclable BC@SiO2-TiO2 hybrid organic-inorganic aerogel membranes for effective in-flow photo-assisted removal of organic pollutants. The hybrid aerogels were prepared by sequential sol-gel deposition of the SiO2 layer over BC, followed ...
Tópico(s): TiO2 Photocatalysis and Solar Cells
2023 - American Chemical Society | ACS Applied Materials & Interfaces
Produção Nacional
Revisado por pares
Hernán Dario Rojas-Mantilla, Saidy Cristina Ayala-Durán, Raquel F. Pupo Nogueira,
This study describes the characterization of Nontronite, a clay mineral with high content of structural iron, before and after iron incorporation and 600 °C heat treatment. The Nontronite was classified as a mesoporous material, with high absorption in the UV–Vis range and band gap energy of 1.9 eV, indicative of the presence of superficial hematite, also verified in XRD analysis. The heat treatment promoted a structure rearrangement and the conversion of other iron phases to hematite, allowing the ...
Tópico(s): Advanced Photocatalysis Techniques
2021 - Elsevier BV | Chemosphere
Produção Nacional
Revisado por pares
Nayara de Melo Costa-Serge, Rosembergue Gabriel Lima Gonçalves, Hernán Dario Rojas-Mantilla, Celso V. Santilli, Peter Hammer, Raquel F. Pupo Nogueira,
The catalytic activity of layered double hydroxides, with and without insertion of copper, was evaluated in a heterogeneous Fenton process for degradation of the antibiotic sulfathiazole (STZ). The characterizations with different techniques revealed lamellar structures formed by stacking of layers containing magnesium, iron, and copper cations. The insertion of copper in the lamellar structure increased the specific area of the material and the degradation kinetics, achieving complete STZ removal ...
Tópico(s): Advanced oxidation water treatment
2021 - Elsevier BV | Journal of Hazardous Materials
Walter Cañón‐Mancisidor, Evgenia Spodine, Diego Venegas‐Yazigi, Darío Rojas, Jorge Manzur, Santiago Álvarez,
Experimental redox potentials of the couples [Cu(R−Ln)(CH3CN)]2+,+, where L1 is bis-(pyridine-2-ylmethyl)-benzylamine, L2 is (pyridine-2-ylethyl)(pyridine-2-ylmethyl)-benzylamine, and R is H, Me, or CF3, were determined in dichloromethane solution. The compounds exhibited one simple quasi-reversible wave over the measured potential range of –500 to +1200 mV, and the E1/2 values varied from +200 to +850 mV versus SCE. These experimental values were correlated with redox potentials calculated using density ...
Tópico(s): Photochemistry and Electron Transfer Studies
2008 - American Chemical Society | Inorganic Chemistry
Fredy Hernán Villalobos Galvis, Carolina Arévalo Ojeda, Fabio Darío Rojas Rivera,
OBJETIVO: Describir las propiedades psicométricas del Suicide Resilience Inventory (SRI-25), adaptado al español, en una muestra de adolescentes y jóvenes escolarizados de San Juan de Pasto, Colombia. MÉTODOS: Se adaptó el SRI-25 al idioma español por medio de una traducción simple. Se contó con 573 participantes, estudiantes de colegios y universidades, de 10 a 25 años de edad. RESULTADOS: En un análisis factorial exploratorio por componentes principales se encontró una estructura de tres factores ...
Tópico(s): Stress and Burnout Research
2012 - Pan American Health Organization | Revista Panamericana de Salud Pública
Mathieu Létourneau, Mélanie Tremblay, Luc Faucher, Dario Rojas, Pascale Chevallier, Yves Gossuin, Jean Lagueux, Marc‐André Fortin,
Manganese oxide (MnO) nanoparticles have been suggested as a promising "positive" MRI contrast agent for cellular and molecular studies. Mn-based contrast agents could enable T(1)-weighted quantitative cell tracking procedures in vivo based on signal enhancement. In this study, ultrasmall MnO particles were synthesized and coated with thiolated molecules (DMSA) and polyethylene glycol (PEG) to allow enhanced cell labeling properties and colloidal stability. This coating allowed the fabrication of individual ...
Tópico(s): Advanced MRI Techniques and Applications
2012 - American Chemical Society | The Journal of Physical Chemistry B
Dace Dzenovska, Iván Darío Rojas Arenas,
Abstract In 1991, barricades in the streets of Rīga, Latvia, shielded important landmarks from Soviet military units looking to prevent the dissolution of the USSR; in 2006, barricades in the streets of Oaxaca, Mexico, defended members of the Popular Assembly of the Peoples of Oaxaca from paramilitary incursions. We employ these two cases to compare the historically specific public socialities and politics formed through spatial and material practices in moments of crisis and in their aftermath. ...
Tópico(s): Politics and Society in Latin America
2012 - Cambridge University Press | Comparative Studies in Society and History
Darío Rojas, Ana M. García, Andrés Vega, Yanko Moreno, Diego Venegas‐Yazigi, M.T. Garland, Jorge Manzur,
The bis-pyridine tridentate ligands (6-R-2-pyridylmethyl)−(2-pyridylmethyl) benzylamine (RDPMA, where R = CH3, CF3), (6-R-2-pyridylmethyl)−(2-pyridylethyl) benzylamine (RPMPEA, where R = CH3, CF3), and the bidentate ligand di-benzyl-(6-methyl-2-pyridylmethyl)amine (BiBzMePMA) have been synthesized and their copper(I) complexes oxidized in a methanol solution to afford self-assembled bis-μ-methoxo-binuclear copper(II) complexes (1, 2, 4, 6) or hydroxo- binuclear copper(II) complexes (3). Oxidation of the nonsubstituted ...
Tópico(s): Magnetism in coordination complexes
2004 - American Chemical Society | Inorganic Chemistry
In light of the abstract theorizations of scholars of transnational social movement networks—as exemplified by Hardt and Negri's Multitude—in this paper I argue for the power of grounded, material engagements with the practices of protest of social movements to transform not just political spaces, but our theoretical landscapes. I compare the practice of setting up and maintaining encampments in the Oaxaca and Occupy movements to argue that the spatial dynamics of occupation in a tent city fuels ...
Tópico(s): Anthropological Studies and Insights
2014 - SAGE Publishing | Environment and Planning D Society and Space
Cristián Lagos, Marco Espinoza, Darío Rojas,
In this paper, we analyse the cultural models (or folk theory of language) that the Mapuche intellectual elite have about Mapudungun, the native language of the Mapuche people still spoken today in Chile as the major minority language. Our theoretical frame is folk linguistics and studies of language ideology, but we have also taken an applied linguistics approach to address the effects that such cultural models have had on language planning and revitalisation. We will propose that the view of the ...
Tópico(s): Cultural and Social Studies in Latin America
2013 - Taylor & Francis | Current Issues in Language Planning
In light of recent debates between affect and emotions in geography, this article focuses on how the emotional landscape of spatial struggles in Oaxaca articulated people together, thereby generating solidarities and a collective sociality offering the potentiality of interconnection that geographers of affect emphasize. Through an analysis of a women's march, I demonstrate how social movements move people, mobilizing them both physically and emotionally, with effects that go beyond a movement's ...
Tópico(s): Sex work and related issues
2015 - Wiley | Antipode
Darío Rojas, Carolina Zambrano, Pedro Salcedo,
ResumenEl presente trabajo propone una metodología de análisis de disponibilidad léxica, basada en la comparación directa de lexicones obtenidos de estudiantes de pedagogía.Esto se hace en respuesta a centros de interés sobre temáticas indicadas como estándar por el Ministerio de Educación de Chile, para la enseñanza de las matemáticas en educación media.La metodología define una nueva medida de disimilitud entre lexicones, basada en la distancia de Levenshtein, la que permite utilizar un enfoque ...
Tópico(s): Educational Methods and Psychological Studies
2017 - SciELO | Formación universitaria
Produção Nacional
Revisado por pares
Sajjad Ullah, Elias P. Ferreira-Neto, Chanchal Hazra, Rashida Parveen, Hernán Dario Rojas-Mantilla, Marcelo L. Calegaro, York E. Serge-Correales, Ubirajara Pereira Rodrigues Filho, Sidney J. L. Ribeiro,
The development of photocatalysts responsive towards a broader region of the solar (UV-to-NIR) light is important for efficient harvesting of sunlight for photochemical and photoelectrical applications. In this study, two photocatalytic systems (BV/LEDs and BV/UCPs where UCPs stands for NaYbF4:Tm3+ upconversion particles) based on bismuth vanadate (BV) are introduced for photocatalytic degradation of both organic dyes (crystal violet, CV) and pharmaceuticals (sulfathiazole, STZ) under a variety of photoactivation ...
Tópico(s): Perovskite Materials and Applications
2018 - Elsevier BV | Applied Catalysis B Environment and Energy
Carolina Zambrano, Darío Rojas, Pedro Salcedo,
El propósito del estudio fue realizar una revisión sistemática, usando la base de datos Scielo, de estudios empíricos sobre disponibilidad léxica. Para ello, se definió dos objetivos: 1) caracterizar la investigación desarrollada en el área de estudios de disponibilidad léxica, 2) describir los aportes al ámbito de la educación de los estudios de disponibilidad léxica. Como criterio de elegibilidad se consideró a los artículos que reportaban hallazgos usando análisis cuantitativo y/o cualitativo ...
Tópico(s): Education and Teacher Training
2019 - Centro de Informacion Tecnologica | Información tecnológica
Iván Darío Rojas Arenas, José Alejandro Durango Marín, Jorge Amado Rentería Vera,
La generación de una cultura investigativa y la formación integral de sus profesionales es una problemática constante para las instituciones de educación superior del paÃs; la separación entre academia y sociedad aÃsla a las universidades del contexto donde interactúan, lo que se refleja en currÃculos poco flexibles, no pertinentes y modelos de enseñanza transmisionista que apelan a la memoria y la acumulación de datos. La investigación formativa surge como una manera de mejorar los ...
Tópico(s): Diverse Applied Research Studies
2020 - Institutul de Stiinte ale Educatiei (Institute of Educational Sciences) | Estudios pedagógicos
Las tecnicas de interpolacion espacial, peso inverso con la distancia (IDW) y Kriging, son las mas comunmente usadas para la estimacion de niveles de contaminante en regiones que tienen un limitado numero de estaciones de monitoreo. Los valores del pico de contaminacion por ozono, medidos en la atmosfera de la region de la Ciudad de Mexico, se consideran como un conjunto de datos muestreados cuya media no es estacionaria. Con el fin de estudiar el efecto de una media no estacionaria sobre el desempeno ...
Tópico(s): Spatial and Panel Data Analysis
2007 - Mexican Society of Physics | Revista Mexicana de Física
Wolfgang Kaim, Christoph Titze, T. Schurr, Monika Sieger, Max Lawson, J. Jordanov, Darío Rojas, Ana M. García, Jorge Manzur,
Abstract The molecular structure of the highly oxygen‐sensitive complex [L 3 Cu I (NCCH 3 )](BF 4 ) ( 1 ) reveals approximately symmetrical coordination by the fac ‐tridentate (tripodal) ligand L 3 = tris(3‐isopropyl‐4,5‐trimethylenepyrazolyl)methane and a rather short Cu I ‐N(acetonitrile) distance of 1.865(5) Å. In CH 2 Cl 2 at −78 °C the colourless compound reacts with O 2 to yield a labile purple intermediate (λ max 517 nm) – presumably a peroxodicopper(II) complex – which decomposes at −30 °C. No such intermediate ...
Tópico(s): Metal complexes synthesis and properties
2005 - Wiley | Zeitschrift für anorganische und allgemeine Chemie
Carolina Zambrano, Alejandro Díaz Mújica, María Victoria Hernández Pérez, Darío Rojas,
El objetivo principal de este estudio fue analizar las estrategias de autorregulación medidas desde la perspectiva del modelo de Zimmerman y desde cuatro dimensiones: i) hábitos inadecuados de regulación; ii) organización del entorno; iii) búsqueda de información; y iv) organización de la tarea. La población consistió de 322 estudiantes de primer año de carreras de pedagogía en Chile. Los datos se analizaron mediante estadísticos descriptivos de confiablidad y diferencia de medias. Los resultados ...
Tópico(s): Education and Teacher Training
2020 - SciELO | Formación universitaria
Darío Rojas, Cristián Lagos, Marco Espinoza,
En el marco de la antropología lingüística, y considerando su aplicación a la planificación del lenguaje y las lenguas, analizamos las representaciones sociales acerca del mapudungun asociadas al saber tradicional, considerándolas como ideologías lingüísticas.En particular, nos enfocamos en aspectos relacionados con la revitalización de esta lengua en contextos urbanos de Chile.Contrastando estas representaciones con las que en otros estudios hemos hallado sobre el tema, constatamos que, mientras ...
Tópico(s): Migration, Education, Indigenous Social Dynamics
2015 - University of Tarapacá | Chungara
This paper describes a new model to automatically generating dynamic formation strategies for robotic soccer applications based on game conditions, regarded to as favorable or unfavorable for a robotic team. Decisions are distributedly computed by the players of a multi-agent team. A game policy is defined and applied by a human coach who establishes the attitude of the team for defending or attacking. A simple neural net model is applied using current and previous game experience to classify the ...
Tópico(s): Distributed Control Multi-Agent Systems
2008 - Elsevier BV | Expert Systems with Applications
Darío Rojas-Avellaneda, José Luis Silván-Cárdenas,
Tópico(s): Vehicle emissions and performance
2006 - Springer Science+Business Media | Stochastic Environmental Research and Risk Assessment
María Liliana Díaz Perdomo, Nelson Darío Rojas Suárez,
Objetivo. Este artículo de revisión pretende ubicar internacionalmente la educación en el posconflicto en Colombia, en relación con las experiencias de otros países que han vivido procesos semejantes. Metodología. Se hizo un rastreo por la bibliografía especializada que relaciona investigaciones sobre el tema. Resultados. Se encontró que en los países más cercanos a la experiencia colombiana sucede algo semejante a lo que pasa en Colombia: mientras la educación conserve parámetros violentos, autoritarios, ...
Tópico(s): Peace and Human Rights Education
2019 - | Eleuthera
David A. Novelo‐Casanova, Gerardo Suárez, Enrique Cabral‐Cano, Enrique Antonio Fernández-Torres, Óscar A. Fuentes-Mariles, E. Havazli, Miguel Á. Jaimes, Erika Danaé López-Espinoza, Ana Lillian Martin‐Del Pozzo, Wendy V. Morales-Barrera, Hipólito L. Moráles-Rodríguez, Amiel Nieto-Torres, Sergio R. Rodríguez-Elizarrarás, Darío Solano-Rojas, Víctor Manuel Velasco Herrera,
Abstract We present a Risk Atlas of Mexico City based on a Geographical Information System (RA-GIS). We identified the prevalent social risk to the more relevant hazards in Mexico City (CDMX): earthquakes, volcanic eruptions, floods, landslides, forest fires, and land subsidence. A total of 274 shape-file maps were generated in this project. Seismic hazard was estimated for return periods (RP) of 20, 125, 250, and 475 years. Three areas in central and northwestern CDMX were identified along the Younger ...
Tópico(s): Remote Sensing in Agriculture
2021 - Springer Science+Business Media | Natural Hazards
Enrique Cabral‐Cano, Darío Solano-Rojas, Talib Oliver‐Cabrera, Shimon Wdowinski, Estelle Chaussard, Luis Salazar-Tlaczani, Francesca Cigna, Charles DeMets, Jesús Pacheco,
Tópico(s): Soil Geostatistics and Mapping
2015 - Copernicus Publications | Proceedings of the International Association of Hydrological Sciences
Darío Solano-Rojas, Enrique Cabral‐Cano, Antonio Hernández‐Espriú, Shimon Wdowinski, Charles DeMets, Luis Salazar Tlaczani, Giacomo Falorni, Adrian Bohane,
273 ResumenEl proceso de subsidencia en la zona metropolitana de la Ciudad de México ha sido reconocido desde principios del siglo pasado y sus efectos tienen graves consecuencias para la operación y mantenimiento de la infraestructura de la ciudad.En este trabajo se presentan las velocidades de subsidencia del terreno obtenidas de Dispersores Persistentes (Persistent Scatterers, PSs) derivados del análisis interferométrico SqueeSAR de datos ENVISAT-ASAR de Radar de Apertura Sintética adquiridos ...
Tópico(s): Latin American Urban Studies
2015 - Sociedad Geológica Mexicana | Boletín de la Sociedad Geológica Mexicana
Darío Solano-Rojas, Shimon Wdowinski, Enrique Cabral‐Cano, Batuhan Osmanoğlu,
Abstract Ground displacements due to changes in soil conditions represent a threat to the stability of civil structures in many urban areas, worldwide. In fast-subsiding areas, regional subsidence (wavelength ~ 1,000’s m) can be dominantly high and, consequently, mask other signals at local scales (wavelength ~ 10–100’s m). Still, engineering and construction applications require a comprehensive knowledge of local-scale signals, which can threaten the stability of buildings and infrastructure. Here we ...
Tópico(s): Geophysical Methods and Applications
2020 - Nature Portfolio | Scientific Reports
Enrique Antonio Fernández-Torres, Enrique Cabral‐Cano, Darío Solano-Rojas, E. Havazli, Luis Salazar-Tlaczani,
Abstract. Land subsidence is a phenomenon present in several cities in central Mexico, and results from a combination of groundwater resources' overexploitation and the local stratigraphic nature. Furthermore, subsidence occurs inhomogeneously in space, producing differential vertical displacements, which affect both the natural media, as well as human-built structures. Subsidence associated structural-vulnerability assessments usually rely on direct field measurements to determine parameters such ...
Tópico(s): Structural Health Monitoring Techniques
2020 - Copernicus Publications | Proceedings of the International Association of Hydrological Sciences
Estelle Chaussard, E. Havazli, Heresh Fattahi, Enrique Cabral‐Cano, Darío Solano-Rojas,
Abstract Many areas worldwide are known to experience land subsidence due to groundwater extraction. It is traditionally assumed that subsidence extent and rates are controlled by groundwater extraction locations and volumes. Here, we reevaluate this assumption in the Mexico City metropolitan area by combining stratigraphic, hydrologic, geodetic, and demographic datasets. Integration of 115 years of leveling with 24 years of Interferometric Synthetic Aperture Radar (InSAR) and 14 years of GPS data ...
Tópico(s): Synthetic Aperture Radar (SAR) Applications and Techniques
2021 - Wiley | Journal of Geophysical Research Solid Earth
Enrique Antonio Fernández-Torres, Enrique Cabral‐Cano, David A. Novelo‐Casanova, Darío Solano-Rojas, E. Havazli, Luis Salazar-Tlaczani,
Tópico(s): earthquake and tectonic studies
2022 - Springer Science+Business Media | Natural Hazards
Carolina Zambrano, Darío Rojas Díaz, Karina Carvajal Cuello, Gonzalo Acuña Leiva,
Every day organizations have more information because their systems produce a large amount of daily operations which are stored in transactional databases.In order to analyze this historical information, an interesting alternative is to implement a Data Warehouse.In the other hand, Data Warehouses are not able to perform predictive analysis for themselves, but machine learning techniques can be used to classify, grouping and predict historical information in order to improve the quality of analysis. ...
Tópico(s): Data Mining Algorithms and Applications
2011 - University of Tarapacá | Ingeniare. Revista chilena de ingeniería