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Copyright of Agroalimentaria is the property of Alejandro Antonio Gutierrez Socorro and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Test laboratories that analyze parameters in environmental matrices usually use standard analysis methods that involve storage, handling of raw materials and management of the waste generated. In the case study laboratory, there is a problem due to the partial control in the generation and disposal of waste, use of raw materials and dangerous reagents, as well as methods that involve pretreatment and sample sizes that generate considerable volumes of waste. The objective is a diagnosis of the environmental performance of the methods used in the analysis of environmental matrices with main emphasis on the case study and respective comparison of two methodologies for the determination of mercury, followed by a multicriteria analysis (TOPSIS, RGB, HEXAGON) to assess the greenness of the analytical process. This article, as a product of the comparative analysis, proposes the implementation of an analytical method based on the EPA 7473 standard (Mercury) in aqueous matrices with a favorable impact on the greenness of the analytical method, a decrease in the carbon footprint and the generation of volumes of contaminated samples. with heavy metals as an alternative to conventional methodologies such as cold vapor atomic absorption spectrophotometry (CVAAS). RGB multicriteria evaluation showed good analytical performance. HEXAGON showed a high penalty for the use of dangerous reagents. Finally, TOPSIS was identified as the method with the greatest simplicity of operation. [ABSTRACT FROM AUTHOR]

Copyright of Bio-grafía. Escritos Sobre la Biología y su Enseñanza is the property of Universidad Pedaggica Nacional and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista de la Sociedad Química del Perú is the property of Sociedad Quimica del Peru and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista ION is the property of Universidad Industrial de Santander and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Espacios is the property of Talleres de Impresos Oma and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this work, the effect of the agitation speed on the thiourea kinetics with thiourea of gold-floated minerals, the concentration of thiourea (TU) that achieved the greatest recovery of gold from its floated concentrates compared with cyanide was determined, along with the kinetic model that controls leaching with thiourea. For this, a "Suction tube" type Baffled reactor is used with mechanical agitation by means of a vane type impeller. The parameters analyzed were: percentage of solids (15%); TU concentration (1, 3, 6, 9, 12 g / L); stirring speed (420, 490, 560, 700 rpm); reaction time (4 hours); effective reactor capacity (27.1 L). An atomic absorption spectrophotometer is estimated to determine the gold concentration. It was determined that the thiourea concentration of 9 g / L was the one that produced the best gold recovery results. The thiourea leaching process adapts to the kinetic diffusion model through the ash layer as a controlling stage. Thiourea, as a leaching agent of the Au concentrate, has a lower percentage (1.74% less) of recovery of this metal than with cyanide during the leaching process at 240 minutes of stirring at a stirring speed of 700 rpm. [ABSTRACT FROM AUTHOR]

Antecedentes: las plantas de beneficio animal generan un volumen considerable de aguas residuales (AR)‚ las cuales presentan concentraciones significativas de materia orgánica. El vertimiento de estos efluentes en cuerpos de agua receptores sin un tratamiento adecuado genera efectos negativos en el medio ambiente y la salud pública. En consecuencia‚ es necesario establecer soluciones efectivas y sostenibles para su estabilización. Objetivo: determinar la eficiencia de los procesos de Coagulación- Floculación (Alternativa 1)‚ Electro-Fenton (Alternativa 2) y Coagulación-Floculación + Electro-Fenton (Alternativa 3) para el tratamiento de AR. Métodos: a partir de muestras de AR colectadas en una planta de beneficio animal‚ fueron optimizadas las variables de pH‚ concentración de coagulante‚ tiempo de reacción y relación molar H2O2/Fe+2 para las alternativas propuestas. La evaluación del desempeño fue estimada mediante el porcentaje de remoción de la Demanda Química de Oxígeno (DQO) y la Turbidez. Así mismo‚ fue estimado el grado de sostenibilidad de cada alternativa mediante el cálculo del índice de química verde. Resultados: las alternativas 1-3 presentaron‚ respectivamente‚ una remoción de 85 %‚ 91‚4 % y 96‚4 % para DQO‚ y de 98 %‚ 99‚3 % y 97‚3 % para turbidez. La alternativa 1 presentó el mayor acercamiento verde (61 %). Conclusiones: la estrategia de combinar Coagulación-Floculación y Electro-Fenton fue la más prometedora para eliminar la carga contaminante de las aguas residuales. A pesar de que todas las opciones evaluadas cumplieron con los parámetros de descarga establecidos por la normatividad‚ la Alternativa 1 presentó ventajas adicionales‚ asociadas al costo de inversión y al acercamiento verde. El presente estudio representa una contribución al desarrollo de tecnologías que permiten estabilizar efluentes generados en las plantas de beneficio animal. [ABSTRACT FROM AUTHOR]

In the last decade, mechanochemistry has emerged as a novel methodology in the search for sustainable alternatives to conventional solvent-based synthetic routes. Its domain has extended beyond inorganic and metallurgical chemistry to become a powerful technique in all areas of chemistry, including organic, organometallic, supramolecular, materials and pharmaceutical chemistry. In this work, we give an overview of the advances and recent achievements of mechanochemistry, emphasizing that mechanochemistry is not only a means for the known chemical processes to be more ecological, but also, it is a tool for the obtaining of new compounds, as well as, for the discovery of processes that are not detected in solution. [ABSTRACT FROM AUTHOR]

Wood constitutes a material susceptible to fungal degradation, presenting frequent and aggressive deterioration when it is put into service. Although over the years compounds have been developed for their protection with various methods of impregnation, many of them present strong environmental questions. The present work focuses on obtaining a preservative with potential antifungal activity for wood through a procedure of low environmental impact. The synthesis of methyl cinnamate (CiM) from cinnamic acid and methanol was carried out by catalysis with acids of Preyssler structure, with a yield of 49% and a selectivity of 100%. Subsequently, the antifungal action of the compound against Gloeophyllum sepiarium (Wulf.: Fr.) P. Karst, fungus causing brown rot was evaluated in-vitro. To do this, the growth of the fungus was comparatively analyzed on a control agarized culture medium and in the presence of CiM. The CiM demonstrated antifungal effect from 2000 ppm, though it was dependent on the incubation temperature. Further research is needed on wood to confirm its potential as a green preservative. [ABSTRACT FROM AUTHOR]

Copyright of Bistua: Revista de la Facultad de Ciencias Básicas is the property of Facultad de Ciencias Basicas de la Universidad de Pamplona and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Electrónica de Enseñanza de las Ciencias is the property of Revista Electronica de Ensenanza de las Ciencias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This manuscript contains a review on the mediation of magnetite, an inorganic material with an inverse spinel structure (FeFe20 4), being used as either catalyst or catalytic support in many chemical reactions of scientific, technological and environmental interest. Because o f current awareness on the efficient and environmentally friendly chemical processes, magnetite has become as a promising material in contexts such as green chemistry, fine chemistry, and heterogeneous catalysis. This iron oxide has been used in several reactions as bulk catalyst, catalytic support of either metals or metal oxides, core in catalysts type core-shell, or as solid modified by grafting with organocatalysts and metal complexes. The catalytic performance of these systems has been described in some chemical processes such as: asymmetric catalysis, environmental catalysis, acid-base catalysis, redox reactions, multicomponent synthesis reactions, and those o f C-C coupling. Particularly, these catalysts have shown large importance in a variety o f reactions: Sonogashira, Sonogashira-Hagihara, Mannich, Ullman, Knoevenagel, Suzuki-Miyaura, and the Fenton heterogeneous reaction, among others. Finally, some technological uses of magnetite in the national context (Colombia) are detailed, and localizing geographically the most important deposits o f this mineral in the Colombian region was intended. [ABSTRACT FROM AUTHOR]

Green Chemistry, as a research area, understood as the development of methodologies to modify products or processes in order to reduce or eliminate the risks posed to the environment and human health. Thus it is allowing research project lines in building knowledge and didactic approaches of the sciences, and to be considered as part of the ministerial programs. The objective of this study was to know and understand the significance given by teachers in the area to green chemistry as a perspective for education. From the speeches issued by teachers participating in the study, four categories, was built. Green Chemistry as: context for teaching chemistry, through significant learning chemistry appropriation, motivating environmental awareness and reflection of the institution and its relationship with teachers. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effect of hydrogen peroxide (H2O2) as an oxygen source in the rhizosphere, in grafted tomato (cv. Durinta/cv Maxifor) and using coconut fiber as substrate The study was conducted from 2009 to 2010. Two treatments were used: a control without (H2O2) (T2) and the other with H2O2 (T1) applied in each irrigation. The parameters evaluated were i- fertigation: oxygen concentration ([O2]), pH, electrical conductivity (EC), and drainage percentage; ii- growth: basal diameter and plant height; iii- yield and iv- fruit quality: firmness, Brix degrees, dry weight, and pH. The average value of [O2] in the irrigation solution through out the crop cycle increased from 9,92 mg/l at T0 to 12,1 mg/l at T1 (P<0,05), meanwhile in the drained solution the value increased from 8,75 mg/l at T0 to 9,22 mg/l at T1 (P<0,05). Although significant differences (P<0.05) were reached in the [O2] between treatments during some periods of the crop cycle, the [O2] in the T0 did not reach a critical threshold that would affect the proper oxygenation of the roots. Therefore, there was no effect of hydrogen peroxide treatment on the growth, productivity and quality of the fruit. [ABSTRACT FROM AUTHOR]

Copyright of Lámpsakos is the property of Fundacion Universitaria Luis Amigo, Facultad de Ingenierias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Massive use of synthetic pesticides in modern agriculture has triggered a number of environmental problems that began to exhibit in 1960 and worsened over time. Poisoning of farm workers, presence of pesticide residues in food and its persistence in the environment, breakdown of natural biological control mechanisms and development of resistance in pest populations are some of the effects of pesticides that threaten human health and environment. In recent decades, various environmental regulations have banned or limited the use of many of these products, stimulating the search for new compounds selective and compatible with the environment and low toxicity to man. In this context we present the principles of green chemistry, a way of doing chemistry based on sustainability, aimed to develop methods and processes that prevent the generation of waste instead of making further treatment thereof. This work addresses and discusses the twelve principles exemplified in the field of pest control. [ABSTRACT FROM AUTHOR]

Copyright of Avances en Ciencias e Ingeniería is the property of Avances en Ciencias e Ingenieria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ciencia e Ingenieria Neogranadina is the property of Ciencia e Ingenieria Neogranadina and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Las amidas sintetizadas de compuestos pirazólicos como núcleo en unión con compuestos organofluorados presentan una amplia gama de actividades biológicas, siendo de gran importancia en síntesis de medicamentos debido a la estabilidad que presentan y parámetros de lipofilicidad. por tanto, estas amidas pueden tener una gran actividad biológica en el tratamiento de enfermedades parasitarias principalmente en el tratamiento de la toxoplasmosis por su capacidad de inhibir enzimas quinasas, la toxoplasmosis es causada por el parasito oportunista protozoario toxoplasma gondii. En este trabajo se presenta el diseño, caracterización por técnicas espectroscópicas, la síntesis de amidas derivadas de 5-aminopirazoles y ácido cinámico mediante reacciones one-pot aplicando la química verde, además de la evaluación in sílico de las propiedades ADMET (absorción, distribución, metabolismo, excreción y toxicidad) de los productos obtenidos. Teniendo en cuenta parámetros de lipofilicidad, solubilidad en agua y absorción gastrointestinal, así mismo como su capacidad inhibidora de quinasas y su biodisponibilidad siendo está dependiendo de la solubilidad. Se encontró que la síntesis de amidas por el método one-pot es una metodología innovadora que permite la síntesis a temperatura ambiente sin condiciones fuertes, a tiempos cortos y con porcentajes de rendimiento altos que varían entre 65%-87% siendo un procedimiento eficaz en cuanto a las propiedades ADMET encontró que para la amida N-(5-(tert-butil)-1H-pirazol-3-yl)-2,3,4-trifluorobenzamida presenta una gran absorción gastrointestinal, una lipofilicidad menos a 5 y una actividad inhibidora de quinasas sin violar las reglas de Lipinski convirtiéndolo en un posible agente activo en la inhibición de quinasas, lo que favorecerá la comunidad científica. [ABSTRACT FROM AUTHOR]