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Copyright of Revista PAMPA is the property of Universidad Nacional del Litoral 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 Nova Scientia is the property of Nova Scientia 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 Actualidad Jurídica Ambiental is the property of CIEMAT, through its Centro Internacional de Estudios de Derecho Ambiental (CIEDA) 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.)

Woody biomass as an energy source varies according to species, environmental conditions that influence their production and dispersal in the territory. The estimation of the suitability of this resource is crucial for sustainable development of agro-forestry and, specifically, of the value chain forest-industry-consumer. Considering this situation, the aim of this paper was to determine the suitability of three types of trees as solid biofuel. A forest species (Quercus ilex L. subsp. ballota (Desf.) Samp); an energy crop (Paulownia spp.) and three fruit species Citrus sinensis (orange), Olea europaea (olive) and Prunus amygdalus (almond). In order to achieve this goal, the paper is focused on the physical, chemical and energetic characteristics of woody biomass of these species. Based on representative sampling, the results obtained qualitatively determined the capabilities and limitations of these species as solid biofuel. The main results of the analysis show that the biomass of all species are suitable for energy use as solid biofuel, with the exception of the orange tree wood that has some limitations for the production of pellets. [ABSTRACT FROM AUTHOR]

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 IBEROAMERICANA. América Latina - España - Portugal is the property of Vervuert Verlag 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 recent decades, the search for natural resources has reconfigured the geopolitical map through new political-economic alliances. Regional studies identify the South American continent as the scene for a potential trade dispute between two poles: the emerging BRICS and the old industrialized countries. The Colombian region known as the highland plains is the epicenter of new economic investments by domestic and international stakeholders who have the intention of developing agribusiness projects, among which promote the biofuels production at the center of the climate change debate. This paper presents research results on the topic of the Territorial Vulnerability Index, bringing to light some of the knots encountered and that legitimize material transformations alongside discursive productions that shape and design the territory. Part of this paper was presented at the I Seminario Internacional Novas Territorialidades e Desenvolvimento Sustentavel, held in Brazil in 2011. [ABSTRACT FROM AUTHOR]

Copyright of Tecnura is the property of Tecnura 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 CES Medicina Veterinaria & Zootecnica is the property of Universidad CES 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 Studiositas is the property of Studiositas 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 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]

In Cuba a significant potential for biogas production and utilization is observed, based on the diversity and volume of contaminating residues generated by the agricultural and agri-food sectors; however, this potential is not accurately known yet to utilize such information in the decision-making processes that contribute to national bioenergy development. In that sense, the objective of the paper is to offer an evaluation of the biogas production and utilization potential in the country. To facilitate the evaluation, the study was divided by sectors (MINAG, MINAL, AzCUBA); within the animal husbandry sector, it was subdivided into poultry, pig (state and cooperative producers) and cattle, but only the productive activity directly linked to MINAG was taken into consideration. In the case of the industry sector (MINAL and AzCUBA), data were taken from the 12 most contaminant industries and from the alcohol distilleries, respectively. The daily potential of biogas production is 674 609 m³, in which the pig and poultry production stand out; this potential means an energy production of 1 477 394 MWh/year, equivalent to 132 856 t of diesel, whose import costs 48 615 065 USD Cuba according to the current prices. Likewise, if the intensity in CO2 of diesel is considered, the emissions prevented due to the substitution of this fossil fuel by biogas are estimated in 440 778 t CO2 eq/year. [ABSTRACT FROM AUTHOR]

This paper presents the used methodology to calculate the present and future potentials of total biomass wastes, from the economic, social, environmental and technological point of view in accordance with the principles of sustainable development. From the values of sugarcane, coffee, rice, and sawmill wastes, through information provided by the main producing companies in Cienfuegos province, it was possible to determine the total energy delivered, as well as the amount of CO2 emitted into the atmosphere. In the case of the bagasse, the total energy was 4.409E+08 MJ, leaving 137 652.9 t CO2 to emit in the atmosphere. For the filter cake it was 7.093E+08 MJ and 221 423.9 tCO2. In the case of coffee and rice residues these values were 4.808E+05 MJ with 184 tCO2 for coffee and 6.34E+07MJ with 19 868.87 tCO2 for rice, respectively. Finally, the total energy for sawmill waste was 4.108E+07 MJ and 2 346.72 tCO2. [ABSTRACT FROM AUTHOR]

In this paper, an analysis of the investment task and projection is performed, as well as technical-economical analysis of the possibilities of production Biodiesel on an industrial scale in "Heriberto Duquesne" Molasses Company. An extensive literature search on the subject of biofuels, and biodiesel in particular was conducted, with a view of selecting the most feasible variant of production and raw materials to carry out the process, where the mud oil, ethyl alcohol and sodium ethoxide catalyst were the most attractive variants. The essential part of the job is the investment task and projection, followed by sizing the equipment for the production of Biodiesel plant, starting from the residual filter cake which provides the Molasses Company. Besides, material balances and energy are analyzed, in addition to equipment design of the chosen section, as well as their technical - economical analysis. [ABSTRACT FROM AUTHOR]

This paper presents how the design approaches with high level of flexibility can reduce the additional costs of the strategies that apply overdesign factors to consider parameters with uncertainty that impact on the economic feasibility of a project. The elements with associate uncertainties and that are important in the configurations of the process integration under a biorefinery scheme are: raw material, raw material technologies of conversion, and variety of products that can be obtained. From the analysis it is obtained that in the raw materials and products with potentialities in a biorefinery scheme, there are external uncertainties such as availability, demands and prices in the market. Those external uncertainties can determine their impact on the biorefinery and also in the product prices we can find minimum and maximum limits that can be identified in intervals which should be considered for the project economic evaluation and the sensibility analysis due to varied conditions. [ABSTRACT FROM AUTHOR]

The depletion of the non-renewable raw materials as petroleum, coal or natural gas as well as the increasing environmental conscience has motivated the valorization of biomass for energy production. Although the first efforts were focused on the development of the first generation biofuels -according to the raw material-, nowadays the research is focused on the second generation biofuels, which allows the transformation of lignocellulosic biomass (from forest or crops wastes, low-priced woods or sawdust) into energy. The transformation of wood into biofuels can be carried out by biological or chemical means. Among the chemical routes, there are three main possibilities: gasification, pyrolisis or hydrolysis. This paper aims to review the technological advances to obtain biofuels by the third route, since it allows using the most abundant forms of biomass, cellulose and hemicelluloses. This chemical process involves several steps: pretreatment of the biomass (by physical or chemical route), hydrolysis of the biomass, dehydration of sugars, aldolization and hydrogenation/dehydration until n-alcanes (biofuels) are achieved. [ABSTRACT FROM AUTHOR]

The current situation due to the exhaustion of fossil fuels, increasing oil prices and environmental difficulties, urgent demand for alternative sources of energy, be an option promising the biodiesel: biofuel produced primarily from oils from oleaginous plants, the availability of which unfortunately, is incapable of replacing the petrodiesel market. The use of microalgae for biodiesel production is an advantageous alternative due to the high lipid content and ideal profile for obtaining biofuels they offer. In addition to this, other attributes are its high microalgae photosynthetic efficiency, which make them excellent sequestering of CO2, its ability to grow both in marine waters, sweet and salty waste, and its relatively high growth rate. However, microalgae culture systems currently have some limitations such as: insufficient information for scaling, difficulty maintaining monocultures, high operating costs for the production and harvesting of microalgae biomass, etc. Given these inconveniences, optimizing their culture systems is essential. The purpose of this paper is to design a research strategy that provides a critical overview of this alternative and bioenergetics, by analyzing the fundamentals of it. [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]

This paper analyzes dominant relations of market that promote the development of agrifuels in low productivity lands in the State of Yucatan. According to the study, the yield of Jatropha curcas es very variable depending on environmental and sociotechnical conditions in agroecosystems. Based on the principles of agroecology, association of pinion with other crops can be an alternative for local use and advisable if it does not compete with subsistence agriculture, due to the risk of displace staple crops and aggravate food scarcity for rural families. From ecological perspective, is not recommended to continue with monocrop in long term despite its high profitability. [ABSTRACT FROM AUTHOR]

Copyright of DYNA - Ingeniería e Industria is the property of Publicaciones Dyna SL 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.)

This paper studies the effect of the mass percentage of the catalyst and the molar ratio oil:alcohol for different alcohol-catalyst systems, in the optimization of alkyl esters production from crude palm oil. Factorial design 32 and response surface methodology were used and quadratic polynomial equations by a multiple regression analysis were obtained. The evaluated answer was the percentage of conversion to glycerine using the norm of the American Oil Chemists' Society, AOCS Ca 14-56. The two variables significantly affect the conversion and the molar ratio effect is larger than the effect of the amount of catalyst. Optimum conditions vary for each system, but in general for the homogeneous catalysts the mass percentage of the catalyst is smaller (1 to 2%) than for heterogeneous (5 to 6%) and large molar ratio are required (1:12-1:40). The properties of fuel obtained are according to American standard requirements for biodiesel. [ABSTRACT FROM AUTHOR]

Copyright of DYNA - Ingeniería e Industria is the property of Publicaciones Dyna SL 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 work has as main objective to design and to validate a System of Technological Surveillance as tool for the search of opportunities of business. He/she offers a theoretical analysis on the current scenario: the call society of the information, the insert in this of the administration of the information, and the paper of the administration of the external information in this organization type. The models identified in the state of the art on the systems of technological surveillance and related concepts are also analyzed. He/she intends the general outline of the proposed system, the stages to continue for their implementation, being argued in the techniques that can be used for it. Finally, the results reached in the definition of investigation macroprojects is exposed, for the definition of opportunities of business in the industry of the cane of sugar and for the position of an international thematic net with the participation of 19 countries. [ABSTRACT FROM AUTHOR]

Copyright of Ciencia Ergo Sum is the property of Universidad Autonoma del Estado de Mexico 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.)