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Copyright of Ingeniería (0121-750X) is the property of 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 Inventum. Ingenieria, Tecnologia e Investigacion is the property of Corporacion Universitaria Minuto de Dios 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 Papel Político is the property of Pontificia Universidad Javeriana 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 Ciencia y Poder Aéreo is the property of Escuela de Postgrados de la Fuerza Aerea Colombiana 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 Investigación Agraria y Ambiental is the property of Revista de Investigacion Agraria y Ambiental 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 Semestre Económico is the property of Sello Editorial de la Universidad de Medellin 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.)

The main objective of this paper was to carry out the evaluation of the liquefaction process on Water Hyacinth biomass. To achieve this, a factorial experimental design with a cubic model was developed, for determining the effect of the variables temperature, time and liquid/solid ratio (L/S) on the response variable Energy Yield (EY). Best results were obtained at 300°C, 60 min and L/S = 10 (exp. 15) with RE of 6.34 MJ/kg biomass, at 300°C, 30 min and L/S = 10 (exp. 5) with EY of 6.31 MJ/kg biomass and at 270°C, 60 min and L/S = 20 (exp. 9) with 6.29 MJ/kg biomass, selecting the conditions of exp. 5 as the most appropriate given the lower L/S ratio and the shorter reaction time. The advantage of catalyst presence in the reaction was evident when comparing the results of the EY in exp. 26 with catalyst (5.9 MJ/kg biomass) and experiment without catalyst (3.3 MJ / kg biomass) under the same conditions. It was also possible to determine that the biooils were composed mainly of aromatic compounds, fatty acids, aliphatic hydrocarbons, ketones, aldehydes and alcohols, and carboxylic acids under more drastic conditions. [ABSTRACT FROM AUTHOR]

Copyright of Revista Latinoamericana de Bioética is the property of Revista Latinoamericana de Bioetica 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 paper densified solid biofuels were produced from the mixture of rice husk, coir, coal and a cassava binder, own department of Cordoba. Initially, it was developed an expanded lattice simplex experimental design to determine the number of runs. Manual densification process was performed; the mixtures were compacted with a pressure of 6000 psi (41,36 MPa) for a hold time of 15 min load. Later tests of mechanical and compressive strength to the briquettes manufactured durability were performed, and analytically calculated the heating value and sulfur emissions each run. It was found that coal is the component that most adversely affects the durability of briquettes, contrary to coconut fiber, which helps to improve the property. All briquettes showed excellent compressive strength, besides no sulfur emissions exceeded 1%. [ABSTRACT FROM AUTHOR]

Copyright of Ingeniería y Competitividad is the property of Universidad del Valle 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.)

Currently one of the energetic challenges is to look for environmentally friendly alternatives that would fulfill in advance the future shortage of oil in the world. Especially, biofuels have turned into one of the most favorable proposals to overcome current demands of the oil. Biofuels are produced from living organisms or from metabolic by-products (organic or food waste products). In this paper a particular application of nanophotonics in the frame of the interaction between light and matter through Surface- Enhanced Raman spectroscopy (SERS) is addressed. As a test prove a Biodiésel sample is considered, the reason relies on the necessity to establish analysis procedures either to be performed during the production or as a quantifying tool to probe integrity during the blending process with diesel. [ABSTRACT FROM AUTHOR]

The arrival of biofuels companies in the Chira Valley, Piura, Peru, in order to produce ethanol on sugarcane cultivation, intensified the agricultural use of land and water in the mid-2000s. This article analyzes the ecological, political and social transformations that biofuels production brought about in the valley. For that purpose the paper describes the role of the state in promoting biofuels and the concomitant land and water-grabbing processes in the valley. It also explores the consequences it had for local communities and medium-sized and small farmers. Ethanol production in the Chira valley produced a profound space transformation because land and water-grabbing processes for biofuels reinforced social inequalities. Information for this article was gathered from primary and secondary sources. This is a qualitative research. Eighteen interviews were conducted in Piura and Lima. [ABSTRACT FROM AUTHOR]

The challenge of using renewable energy sources means that the production of biofuels and the design of their supply chains, should be pursue environmental and social benefits beyond the purely economic benefit. In this paper are revised some discussions about the impact of biofuels on sustainability and researching in the biofuel supply chains design of first and second generation via mathematical optimization, to analyze how environmental and social concerns have been considered in this problem. Finally, techniques most used optimization were identified and the review found that the concept of sustainability in the design of biofuel supply chains through modeling, is just beginning. [ABSTRACT FROM AUTHOR]

In this paper, we make a critical assessment of the main motivations for the development, use and policymaking of biofuels through state of the art studio. From this it shows that the expected expansion in biofuels through state of the art studio. From this it shows that the expected expansion in biofuels production is due to benefits they offer, as a contribution to mitigating climate change and reducing global dependence on scarce and uncertain oil supplies and on the other hand, helps to reduce oil prices. Also there are a number of motivations that drive the search for alternative energy sources, within which biofuels production holds great interest today, these are grouped in three areas: environmental, economic and political, and of social nature. Among them are identified as key environmental pollution, demand and energy security reasons. To these positive elements are opposed a number of difficulties in the development and use of biofuels. Among them are those related to the availability and sustainable supply of feedstock, limiting properties and others that change over time, there are many users who are not familiar with them. Considering that the major fraction of the costs in biomass power generation originates from logistics operations, these systems have to be located near the source of biomass and hence be decentralized. The size depends among other factors on the availability of biomass. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Investigaciones Políticas y Sociológicas (RIPS) is the property of Universidad de Santiago de Compostela, Servicio de Publicaciones 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 Acta Universitaria is the property of Universidad de Guanajuato/Acta Universitaria 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 UNISCI Discussion Papers is the property of Unidad de Investigaciones Sobre Seguridad y Cooperacion International (UNISCI) 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 Salud Pública is the property of Universidad Nacional de Colombia 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.)