Elena Otazo | Universidad Autonoma del Estado de Hidalgo (original) (raw)

Papers by Elena Otazo

Arsenic is a toxic metalloid that is present in air, water and soil. Soil bacteria play an impor... more Arsenic is a toxic metalloid that is present in air, water and soil. Soil bacteria play an important role in the oxidation of this element. This article describes the use of plants as bioassay for the detection of genotoxicity induced leaching of soils with arsenic (As). Test micronuclei induction was used stem cells pollen Tradescantia clone 4430 (Trad-MCN). The results demonstrate that the micronuclei frequency was higher for soil leachate from the community of the Salitre, Hidalgo, and the community of Bella Vista del Rio, Queretaro, in Mexico. Compared with the control group of leachates soil for the Municipality of Queretaro. In all cases there was a significant difference (Tukey p> 0,05). Also resulting in good linear correspondence R 2 = 0,94 and the slope of the equation that represents a velocity induced MNs 100/0,05 tetrads each μgAs.L -1 .

ABSTRACT La información sobre las descargas de aguas residuales municipales e industriales, se to... more ABSTRACT La información sobre las descargas de aguas residuales municipales e industriales, se tomaron de las bases de datos registradas en el Inventario Nacional de Descargas de Aguas Residuales (INDAR) con que cuenta la Gerencia Estatal (CNA, 2004). A partir de la información de dicho inventario, se realizó una selección de las descargas de acuerdo con el caudal y el giro industrial. Se determinó su posible ubicación geográfica (Tabla 1). Se contactó a las áreas de ecología y organismo operador, para el apoyo en la ubicación de las descargas de aguas residuales. Con posterioridad, se realizó el recorrido de campo por los ríos Tepeji y Tula para evaluar los sitios de muestreo a considerar. Del análisis del inventario de des- cargas de aguas residuales proporcionado por CNA en Hidalgo, se determinaron las descargas directas a los cau- ces que implicarían mayor carga contaminante y volumen; se ubicaron puntos aguas arriba y abajo de estas descar- gas, como puntos de monitoreo y aforo. Posteriormente, se realizó un recorrido prospectivo, a los 24 sitios, seleccionándose 17,7 en ríos, 2 en afluentes y 8 en descargas de aguas residuales, para ser considerados en el presente estudio (Tabla 2). Se realizó la recolecta de aguas y las determinaciones de parámetros in situ de temperatu- ra del agua, pH y conductividad. El balance de masa determina las concentraciones de los minerales conservativos, bacterias coliformes y de los com- ponentes no conservativos. Además de los flujos de masa, otros procesos incluidos en el balance de material son: transformación de nutrientes, producción de algas, deman- da carbonosa y del bentos, reaereación atmosférica y el efecto de estos procesos en el balance de oxígeno disuel- to. La Figura 2 muestra las interacciones entre los paráme- tros modelados por el QUAL2E, el ciclo del nitrógeno en cuatro partes (nitrógeno orgánico, amoniacal y nitrógeno como nitrito y nitrato) y el ciclo de fósforo en dos etapas (orgánico y disuelto).

Tropical and …, 2009

El Limón Lagoon belongs to the Reforma county, in the State of Chiapas, Mexico. Massive fish kill... more El Limón Lagoon belongs to the Reforma county, in the State of Chiapas, Mexico. Massive fish killings have occurred in the lagoon, demanding a deeper study to determine the pollution state of the lagoon, as well as the possible cause of the deaths. Results show ...

DYNA, 2007

SciELO - Scientific Electronic Library Online Browse SciELO, SciELO Library Error Detector An une... more SciELO - Scientific Electronic Library Online Browse SciELO, SciELO Library Error Detector An unexpected error occurred in SciELO servers. Click on the SciELO logo to browse the SciELO Library or use the browser "BACK" button to return to the previous page. ...

Avances en Ciencias e Ingeniería, 2012

El objetivo del trabajo ha sido aplicar los modelos de GAB para evaluar isotermas de adsorcion se... more El objetivo del trabajo ha sido aplicar los modelos de GAB para evaluar isotermas de adsorcion segun niveles de actividad de agua (aW) en tres variedades de cereales para desayuno y su correlacion con otros modelos matematicos. Se concluye que en el cereal hojuelas de maiz, los incrementos de masa por adsorcion de agua son mas marcados que en los demas cereales, aunque se produce a velocidades menores; le siguen las hojuelas de trigo y de arroz. Esto se explica, por los mas altos contenidos de azucares en las hojuelas de maiz y por los contenidos de almidones mas altos tanto en maiz como en trigo. Corrobora que en productos alimenticios ricos en azucares no se presentan altas velocidades de adsorcion de agua a bajos niveles de aW, pero suelen presentar altas capacidades de adsorcion, solo que lo hacen de manera mas lenta, por la higroscopicidad de los azucares

1 Orthogonal Array Design 2 3 Roberto Antonio Canales Flores a, Francisco Prieto García a*, Elena... more 1 Orthogonal Array Design 2 3 Roberto Antonio Canales Flores a, Francisco Prieto García a*, Elena María Otazo 4 Sánchez a, Ana María Bolarín Miró b, Otilio Arturo Acevedo Sandoval a 5 6 a Academic Area of Chemistry, bAcademic Area of Materials and Earth Sciences. 7 Autonomous University of Hidalgo State, Road Pachuca-Tulancingo km 4.5, C.P. 42186. 8 Pachuca, Hidalgo, Mexico. 9 * Corresponding author. E-mail address: prietog@uaeh.edu.mx (F. Prieto García) 10 11 Abstract 12 This research demonstrates the optimization and production of biochar from barley husk 13 (BH), corn cob (CC), and Agave salmiana leaves (AL) via pyrolysis in a muffle furnace. 14 Taguchi experimental design (L9) was applied to conduct the experiments at different 15 levels by altering four operating parameters. Carbonization temperature (300–500 oC), 16 carbonization time (30–90 min), precursor mass (2–5 g) and N2 flow rate (100–200 cc/min) 17 were the variables examined in this study. The effect of the parameters...

The state of Hidalgo, Mexico presents an important environmental problem that manifests itself in... more The state of Hidalgo, Mexico presents an important environmental problem that manifests itself in different ways. To identify the sources, types and the magnitude of pollutants, an inventory of sources of industrial and domestic pollution for air, water and soil in ten municipalities of the Huasteca Region of the state was carried out using the technique of Rapid Assessment of Sources of Environmental Pollution and the results are reported in this paper. A total of combined pollutants emitted was 116 978.95 tons/year. Gasoline vehicles contributed 11 039 tons/year of air pollutants and diesel vehicles 1521 tons/year. For water, industrial sources contributed 22 496 tons/year and domestic effluents 15 776 tons/year. Soil pollution was a result of industrial solid waste, 4025 tons/year, and municipal solid waste, 62 121 tons/year. By municipality, Huejutla de Reyes is the most polluted in air, water and soil, with 53 % of the regional total. These results were evaluated in relation to...

Flores, R. A. C., F. P. García, E. M. O. Sánchez, A. M. B. Miró and O. A. A. Sandoval, 2018. Pyro... more Flores, R. A. C., F. P. García, E. M. O. Sánchez, A. M. B. Miró and O. A. A. Sandoval, 2018. Pyrolysis optimization of agricultural waste using Taguchi L9 orthogonal array design. Bulg. J. Agric. Sci., 24 (2): 263–273 This research demonstrates the optimization and production of biochar from barley husk (BH), corn cob (CC), and Agave salmiana leaves (AL) via pyrolysis in a muffl e furnace. Taguchi experimental design (L9) was applied to conduct the experiments at different levels by altering four operating parameters. Carbonization temperature (300-500°C), carbonization time (30-90 min), precursor mass (2-5 g) and N2 fl ow rate (100-200 cc/min) were the variables examined in this study. The effect of the parameters on the biochar yield was investigated, and the important parameters were identifi ed employing analysis of variance (ANOVA). The optimum conditions for maximum biochar yield were: carbonization temperature of 400°C, carbonization time of 30 min, precursor mass of 2 g, and...

Revista Internacional De Contaminacion Ambiental, Aug 1, 2010

Avances En Ciencias E Ingenieria, 2012

El objetivo del trabajo ha sido aplicar los modelos de GAB para evaluar isotermas de adsorción se... more El objetivo del trabajo ha sido aplicar los modelos de GAB para evaluar isotermas de adsorción según niveles de actividad de agua (a W) en tres variedades de cereales para desayuno y su correlación con otros modelos matemáticos. Se concluye que en el cereal hojuelas de maíz, los incrementos de masa por adsorción de agua son más marcados que en los demás cereales, aunque se produce a velocidades menores; le siguen las hojuelas de trigo y de arroz. Esto se explica, por los más altos contenidos de azúcares en las hojuelas de maíz y por los contenidos de almidones más altos tanto en maíz como en trigo. Corrobora que en productos alimenticios ricos en azúcares no se presentan altas velocidades de adsorción de agua a bajos niveles de a W , pero suelen presentar altas capacidades de adsorción, sólo que lo hacen de manera más lenta, por la higroscopicidad de los azúcares.

ABSTRACT Resumen Se prepara un electrodo selectivo (ESI) a plomo (II), utilizando como ionóforo l... more ABSTRACT Resumen Se prepara un electrodo selectivo (ESI) a plomo (II), utilizando como ionóforo la 1-furoil-3,3-dietiltiourea (FDET), y el tributil fosfato (TBP) como plastificante, inmovilizados en PVC, sobre un soporte de resina conductora.. El electrodo exhibe una pendiente nerstiana de 29,8 mV/década, y un intervalo de respuesta lineal de 9,42 · 10 -6 -2,97 · 10 -3 mol/dm 3 . El tiempo de respuesta del electrodo es menor de 20 segundos, y su tiempo de vida es superior a un mes. Se determina el coeficiente de selectividad (K AB Pot) para los iones Cu 2+ , Cd 2+ y Ca 2+ y la influencia del pH en la respuesta del electrodo. Palabras clave: Electrodo Selectivo (ESI), 1-furoil-3,3-dietiltiourea, membrana líquida. Abstract Lead Ion selective electrodes, ISE, based on plasticized membranes with 1-furoyl 3,3 diethylthiourea as ionophore and tributyl phosphate as plasticizer have been developed. The membranes are applied on a support of conductor resin. Some parameters of evaluation of these electrodes are presented in this work. The electrode has linear response in the concentration range of the 9,42 · 10 -6 -2,97 · 10 -3 mol/dm 3 , with slopes of 29,8 mV/decade. The static response time obtained was ~20 seconds. The selectivity coefficients K AB Pot , for the ions Cu 2+ , Cd 2+ y Ca 2+ were calculated employing the mixed solutions method. The pH dependence of the potential was analyzed.

Separation Science and Technology, 2014

MRS Proceedings, 2007

ABSTRACTMaterials with high specific surface areas such as pillared clays and zeolites have been ... more ABSTRACTMaterials with high specific surface areas such as pillared clays and zeolites have been studied and can be used to remediate contaminated water. Chemical functionality or compounds can be anchored or attached to the surface of a low-cost material used as a support matrix. This work studied the suitability of inexpensive natural mineral soils to decontaminate waste water from mine and metallurgic industries. Native mineral soils were also impregnated with commercial 1,3 diphenyltiourea (DFT) to improve retention of heavy metal ions. The natural mineral soils were from Hidalgo State in Mexico: white marble (calcite: CaCO3), volcanic gravels named “red and black tezontles” (anorthite matrix: CaO.Al2O3.(SiO2)2 with FexOy and PbxOy), green zeolites (mordenite: Na2CaK2. OAl2O3.10SiO2.7H2O) and kaolin (kaolinite: Al2O3(SiO2)2.H2O). They were ground and sieved. The 50 mesh fraction was studied by Raman and FTIR spectroscopy, X ray powder diffraction and scanning electronic microsco...

Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2006

Two series of coordination complexes of CdCl(2) and HgCl(2) with 3-monosubstituted and 3,3-disubs... more Two series of coordination complexes of CdCl(2) and HgCl(2) with 3-monosubstituted and 3,3-disubstituted 1-furoylthioureas were prepared and characterized. These complexes were obtained with a medium to high yield from ethanolic solutions of both ligand and salt. The formed complex results from the salt-ligand interaction with participation of both the salt anion and cation. Information on the coordination chemistry of these complexes was derived from thermal stability data, and IR, Raman and (13)C CPMAS NMR spectra. On coordination the electronic structure of these ligands changes as a whole, affecting practically all their vibrational pattern, however, within that complex pattern some vibrations provide valuable information on the nature of the studied complexes. These thiourea derivatives behave as neutral ligands, which coordinate the metal ion through the sulfur atom of the thiocarbonyl group. This fact is supported by the observed frequency shift, to lower values, in the nu(CS) vibration on the coordination and the appearance of a low frequency Raman line which was assigned to the metal-sulfur stretching, nu(M-S), in the formed complex. The frequency of the nu(CO) vibration always increases on complex formation, which discards the participation of the carbonyl group in the coordination process. The complexation takes place preserving the free ligand conformation, established from intra-molecular interactions, particularly in 3-monosubstituted ligands. Such features of the studied ligands and their complexes are also supported by (13)C CPMAS NMR spectra. This spectroscopic information correlates with the reported behavior of the ligands in ion selective electrodes.

Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2005

Raman and IR spectra of two series of 1-furoylthiourea derivatives (19 compounds) were recorded a... more Raman and IR spectra of two series of 1-furoylthiourea derivatives (19 compounds) were recorded and compared in order to identify the vibrations, which involve contributions from motions within the thioureido (NCSN) core. This procedure allowed an unequivocal identification of the nu(CS) vibration in these spectra. In 3-monosubstituted furoylthioureas (Series 2) the carbonyl group and the proton on N(3) are engaged in a strong hydrogen bond interaction. This leads to an &amp;quot;S&amp;quot;-shaped conformation of the CO and CS groups where these donor sites reach a maximum separation. In this conformation, the nu(CO) vibration is not influenced by the substituent. In the absence of that hydrogen bridge, in 3,3-disubstituted thiourea derivatives (Series 1), the CO and CS groups adopt an &amp;quot;U&amp;quot;-shaped conformation. In this conformation, the nu(CO) vibration shows a pronounced substituent dependence. These thiourea derivatives have been tested as ionophores for heavy-metal ion selective electrodes and their behavior in that sense correlates with the observed Raman and IR absorptions. The best performance in that application corresponds to compounds of Series 2, which showed the highest frequency values of the nu(CS) vibration. This fact was related to an appropriated nucleophilic character of the sulphur atom. From these data, Raman and IR spectra of these thiourea derivatives could be used as a predictor on their expected behavior in analytical applications as ionophores.