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Copyright of International Journal of Professional Business Review (JPBReview) is the property of Open Access Publications LLC 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 Brazilian Journal of Production Engineering / Revista Brasileira de Engenharia de Produção is the property of Brazilian Journal of Production Engineering 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 Ciência Florestal (01039954) is the property of Ciencia Florestal 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 Nativa is the property of Revista Nativa 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 Organizações Rurais & Agroindustriais is the property of Organizacoes Rurais & Agroindustriais 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 GeSec: Revista de Gestao e Secretariado is the property of Sindicato das Secretarias e Secretarios do Estado de Sao Paulo (SINSESP) 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 Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e 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 Revista IRRIGA - Brazilian Journal of Irrigation & Drainage is the property of Revista IRRIGA (Brazilian Journal of Irrigation & Drainage) 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.)

Global energy demand has increased significantly and nations have come to depend on petroleum as their primary energy source. However, the use of this raw material tends to have limitations regarding long-term availability. Thus, the study of different raw materials for the production of renewable fuels is of great importance. The present study had as objective the production of biodiesel from corn and the study of the physicochemical characteristics of the diesel-biodiesel mixtures in the proportions of 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80 % and 90%. Biodiesel was produced by methyl route, using sodium hydroxide (NaOH) as a catalyst. The transesterification took place under magnetic stirring, respecting the proportion of 6 moles of methyl alcohol to 1 mole of vegetable oil, 1% of NaOH in volumetric basis and stirring time of 60 minutes. An increase in specific mass and kinematic viscosity was observed in relation to the proportion of biodiesel in the blends. The results indicated that the production of biodiesel from corn oil had a satisfactory average yield of 94.29% and that only the diesel-biodiesel blends B10, B20, B30, B40 and B50 presented specific mass and kinematic viscosity in patterns consistent with the norm. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Applied Technology for Agricultural Science / Revista Brasileira de Tecnologia Aplicada nas Ciências Agrárias is the property of Brazilian Journal of Applied Technology for Agricultural Science 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.)

Renewable energies arise as a way of mitigating the environmental damages caused by traditional of energy sources, as well as offering a diversification of the energy matrix. Among the many energetic vectors possible, microalgae are a good choice for power generation due to their high conversion capacity of solar energy into chemical energy, broadening the possibilities of obtaining algal biomass in energetic applications. Through them, it's possible to produce biodiesel, bioethanol, methane gas and hydrogen gas as fuel. The present work evaluates the energy potential of the microalga Oedogonium sp. through its physical-chemical analysis and the calorific value, as well as the viability of its densification in the form of pellets, to be used as a solid combustion material. For this, calorimetric, thermogravimetric and immediate analyzes were performed, where in the latter it was possible to obtain the moisture, ash, fixed carbon and volatile contents present in the biomass. The results found in the analyzes were satisfactory, in which the higher calorific value was 16,13 MJ/kg, higher than that found for firewood, and in the standards imposed by European, Swedish and international standards for pellets. [ABSTRACT FROM AUTHOR]

Copyright of Nativa is the property of Revista Nativa 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 Caatinga is the property of Revista Caatinga 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.)

With the ever-increasing usage of fossil fuels comes its impacts to the environment, such as polluting gases generated by its combustion and the crescent reports of spillage into the soil. Biofuels on the other hand, are less polluting and cause less impact to the environment. In order to monitor biofuel's degradation in soil, a study was carried out in order to evaluate the degradation of B100 biodiesel when in contact with vermicompost (earthworm humus) and compost (gardening waste). The materials were contaminated with different percentages of soy's B100 biodiesel and arranged in PVC (polyvinyl chloride) columns with removable stages and were confined for a 45 days period. Every 15 days, samples were taken and extractions of the remaining biodiesel via soxhlet system were carried out. Results show that when comparing both treatments, vermicompost performed better degrading B100 at a rate of 10% during the studied period. Such findings might work as evidence that this technique may present itself as an alternative for bioremediation of a biodiesel contaminated site. [ABSTRACT FROM AUTHOR]

Copyright of Nativa is the property of Revista Nativa 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 Brazilian Journal of Wood Science / Revista Ciência da Madeira is the property of Brazilian Journal of Wood Science 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 Scientiarum: Technology is the property of Universidade Estadual de Maringa 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 study analyzes the changes through time and space of the social capital in the rural settlement Santo Inácio Ranchinho, Campo Florido, Minas Gerais, as a determining factor of survival of this community to face the expansion of sugarcane companies in the Cerrado Mineiro region. In addition to being a valuable and structurally intangible capital, the social capital is also an immeasurable and inexhaustible force of cohesion between humans that allows the creation of a form of community resistance in this settlement born from the agrarian reform in the Triângulo Mineiro. This settlement, in particular, adopted a mixed form of massive and traditional farming culture to survive. As a working methodology, semi-structured interviews were conducted with community members who work as agricultural and livestock producers, as well as interviews with settlement rural extensionists from government and non-governmental organizations. The results indicate that there are multiple forms of social capital; they are present not just in pure and one-dimensional forms of social capital because members of the community have created new ways to establish complex social networks to thrive as a productive community. This settlement as a social structure does not disappear because its sophisticated social network is continuously building a dynamic social capital, which is still adapting to a global world. The globalization of biofuel production has changed the agricultural frontiers, and consequently, this community has responded with the reinvention and adaptation of the cultural, economic and social capital to pursue a peaceful and sustainable way of living and resistance. [ABSTRACT FROM AUTHOR]

The aim of the present study was to estimate the energy balance (output/input ratio) of the canola crop for biodiesel production, under Brazilian conditions. Fossil energy expended in the production of 600kg of oil per hectare was 7,146,537kcal. The estimated energy yield per hectare was 9,930,000kcal from the production of 1,500kg ha-1 of seeds (40% oil and 60% oil cake), which resulted in an energy balance of 1.39. Results indicated the viability of biofuel production from canola, but also showed the need to improve the technology used to increase the energy and economic balance ratios. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the initial growth, the basic density, the production of biomass and chemically analyzing of the wood and bark of two Eucalyptus clones (a hybrid of Eucalyptus urophylla S.T. Blake, a hybrid tri-cross Eucalyptus urophylla S.T. Blake x (E. camaldulensis Dehn x E. grandis Hill ex Maiden)) and a hybrid Corymbia citriodora (Hook) K. D. Hill & L. A. Johnson x C. torelliana (F. Muell) K. D. Hill & L. A. Johnson distributed in three planting spacings: 3x3m, 3x1,5m, 3x1m, at the age of 12 months. The study was conducted in an experiment located in the county Itamarandiba, MG, in a completely randomized design with four replications, in a factorial 3x3, considering how levels of the factors the different clones and planting spacings. It was observed for the three clones that the 3x3m spacing provided plants with greater growth in diameter at breast height (DAP) in relation to the other spacings. The different planting spacings did not induce the variation of the basic specific mass of the wood and the bark in the studied clones. The increase in planting density had a direct relation with biomass production per unit area. There was a decrease in lignin contents in the wood for two clones of Eucalyptus, the larger spacing for the denser spacings. [ABSTRACT FROM AUTHOR]

Copyright of Informe Gepec is the property of Informe Gepec 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.)

In a competitive world, the way a firm establishes its organizational arrangements may determine the enhancement of its core competences and the possibility of reaching new markets. Firms that find their skills to be applicable in just one type of market encounter constraints in expanding their markets, and through alliances may find a competitive form of value capture. Hybrid forms of organization appear primarily as an alternative to capturing value and managing joint assets when the market and hierarchy modes do not present any yields for the firm's competitiveness. As a result, this form may present other challenging issues, such as the allocation of rights and principal-agent problems. The biofuel market has presented a strong pattern of changes over the last 10 years. New intra-firm arrangements have appeared as a path to participate or survive among global competition. Given the need for capital to achieve better results, there has been a consistent movement of mergers and acquisitions in the Biofuel sector, especially since the 2008 financial crisis. In 2011 there were five major groups in Brazil with a grinding capacity of more than 15 million tons per year: Raízen (joint venture formed by Cosan and Shell), Louis Dreyfus, Tereos Petrobras, ETH, and Bunge. Major oil companies have implemented the strategy of diversification as a hedge against the rising cost of oil. Using the alliance of Cosan and Shell in the Brazilian biofuel market as a case study, this paper analyses the governance mode and challenging issues raised by strategic alliances when firms aim to reach new markets through the sharing of core competences with local firms. The article is based on documentary research and interviews with Cosan's Investor Relations staff, and examines the main questions involving hybrid forms through the lens of the Transaction Cost Economics (TCE), Agency Theory, Resource Based View (RBV), and dynamic capabilities theoretical approaches. One focal point is knowledge "appropriability" and the specific assets originated by the joint venture. Once the alliance is formed, it is expected that competences will be shared and new capabilities will expand the limits of the firm. In the case studied, Cosan and Shell shared a number of strategic assets related to their competences. Raízen was formed with economizing incentives, as well to continue marshalling internal resources to enhance the company's presence in the world energy sector. Therefore, some challenges might be related to the control and monitoring agents' behavior, considering the two-part organism formed by distinctive organizational culture, tacit knowledge, and long-term incentives. The case study analyzed illustrates the hybrid arrangement as a middle form for organizing the transaction: neither in the market nor in the hierarchy mode, but rather a more flexible commitment agreement with a strategic central authority. The corporate governance devices are also a challenge, since the alignment between the parent companies in the joint ventures is far more complex. These characteristics have led to an organism with bilateral dependence, offering favorable conditions for developing dynamic capabilities. However, these conditions might rely on the partners' long-term interest in the joint venture.En un mundo competitivo, la manera como una empresa establece sus disposiciones organizacionales puede determinar la mejora de sus competencias esenciales y la posibilidad de alcanzar nuevos mercados. Empresas que actúan en un solo tipo de mercado encuentran restricciones para expandirse, no obstante, pueden encontrar una forma competitiva de crear valor por medio de alianzas estratégicas. Las formas híbridas de organización aparecen principalmente como una alternativa a la hora de capturar valor y administrar activos, cuando el mercado y la jerarquía organizacional no presentan rendimientos para la competitividad de la empresa. Como resultado, esta forma presenta desafíos, tales como la asignación de derechos y problemas de agencia. El mercado de biocombustibles ha presentado cambios continuos a lo largo de los últimos diez años. Nuevos acuerdos entre empresas aparecieron como un medio de participar o sobrevivir en el escenario de la competencia global. Dada la necesidad de capital para lograr mejores resultados, se ha producido un movimiento constante de fusiones y adquisiciones en el sector de los biocombustibles, especialmente desde la crisis financiera de 2008. En 2011 existían cinco grandes grupos en Brasil, con una capacidad de molienda de más de 15 millones de toneladas al año: Raízen (joint venture formada por Cosan y Shell), Louis Dreyfus, Tereos Petrobras, ETH, y Bunge. Las principales empresas petroleras han puesto en práctica una estrategia de diversificación como forma de protección contra el aumento del costo del petróleo. Por medio del estudio de la alianza entre Cosan y Shell en el mercado brasileño de biocombustibles, se analizan en este trabajo el modo de gobernanza y los desafíos que se plantean cuando las empresas intentan conquistar nuevos mercados compartiendo competencias básicas con las empresas locales. Este artículo se basa en investigación documental y entrevistas con profesionales del departamento de Relaciones con Inversores de Cosan. Se examinan las principales cuestiones que involucran formas híbridas por medio de la Teoría de los Costos de Transacción, Teoría de la Agencia, Teoría de Recursos y Capacidades (RBV) y el estudio teórico de las Capacidades Dinámicas. Un punto central es la apropiación del conocimiento y los activos específicos generados por la alianza estratégica. Una vez que se forme la alianza, se espera que las competencias sean compartidas y que las nuevas capacidades amplíen los límites de la empresa. En el caso estudiado, Cosan y Shell comparten una serie de recursos estratégicos relacionados con sus competencias. Raízen se formó a partir de incentivos económicos y siguió reuniendo recursos internos para mejorar la presencia de la compañía en el sector energético mundial. Sin embargo, algunos problemas podrían relacionarse con el control y el monitoreo o seguimiento de los agentes, teniéndose en cuenta que la empresa Raízen está formada por dos partes que presentan cultura organizacional, conocimiento tácito e incentivos de largo plazo distintos. El caso en estudio ilustra un acuerdo híbrido como una forma alternativa de organizar las transacciones entre empresas: ni de mercado ni de jerarquía, sino más bien un término de compromiso más flexible con una autoridad central. Los dispositivos de gobernanza corporativa son asimismo un desafío, ya que la alineación entre empresas semejantes en joint ventures es mucho más compleja. Estas características dan lugar a un organismo con dependencia bilateral, lo que ofrece condiciones favorables al desarrollo de capacidades dinámicas. Sin embargo, tales condiciones dependen de los intereses a largo plazo de cada parte de la alianza estratégica.Em um mundo competitivo, a maneira como uma firma estabelece seus arranjos organizacionais pode determinar sua capacidade de ampliar suas competências essenciais, bem como a possibilidade de atingir novos mercados. Empresas que atuam em apenas um mercado encontram obstáculos para se expandir e por meio de alianças elas encontram uma forma competitiva de criar valor. Formas híbridas apresentam-se primeiramente como alternativas de capturar valor e gerenciar ativos quando o mercado e a hierarquia organizacional não apresentam ganhos para a competitividade da firma. Como resultado, essa forma apresenta desafios como a alocação de direitos e os problemas de agência. O mercado de biocombustíveis tem apresentado mudanças contínuas nos últimos dez anos. Novos arranjos intra-firmas apareceram como um caminho para participar ou sobreviver no cenário de competição global. Dada a necessidade de capital para atingir melhores resultados, tem havido um movimento consistente de fusões e aquisições no setor de biocombustíveis, principalmente desde a crise financeira de 2008. Em 2011 existiam cinco grandes grupos no Brasil com capacidade de moagem de mais de 15 milhões de toneladas por ano: Raízen (joint venture entre Cosan e Shell), Louis Dreyfus, Tereos Petrobras, ETH e Bunge. Grandes companhias de petróleo têm adotado uma estratégia de diversificação como forma de proteção contra os crescentes custos do petróleo. Por meio da análise da aliança entre Cosan e Shell no mercado de biocombustíveis brasileiros, neste artigo avalia-se o modo de governança e os desafios que surgem quando as firmas buscam atingir novos mercado pelo compartilhamento de competências essenciais com empresas locais. Neste artigo tem-se por base pesquisa documental e entrevistas com analistas do departamento de Relações com Investidores da Cosan e examinam-se as questões centrais que permeiam as formas híbridas por meio de Teoria dos Custos de Transação, Teoria da Agência, Visão Baseada em Recursos e da abordagem das capacidades dinâmicas. Um ponto focal neste estudo é a apropriação do conhecimento e os ativos específicos gerados com a aliança estratégica. Uma vez que a aliança é formada espera-se que as competências sejam compartilhadas e novas capacidades expandam os limites da firma. Cosan e Shell compartilham uma série de recursos estratégicos relacionados às suas competências. A Raízen foi formada com base em incentivos econômicos, bem como na melhoria dos recursos internos que aumentassem a presença da empresa no setor de energia mundial. Entretanto, alguns desafios podem estar relacionados ao controle e ao monitoramento dos agentes, considerando que a empresa Raízen é composta por duas partes com culturas organizacionais, conhecimentos tácitos e incentivos de longo prazo distintos. O caso estudado ilustra um arranjo híbrido como forma alternativa de organizar as transações entre firmas: nem mercado nem hierarquia, mas sim uma forma mais flexível de arranjo com uma autoridade central. Os mecanismos de governança corporativa são igualmente um desafio, uma vez que o alinhamento entre companhias parentes em joint ventures é bastante complexo. Essas características conduzem a um organismo com dependência bilateral, oferecendo condições favoráveis para desenvolver capacidades dinâmicas. Entretanto, essas condições dependem dos interesses de longo prazo de cada participante da aliança estratégica.

O Brasil, terceiro maior produtor de biodiesel do mundo e terceiro maior produtor mundial de frango, pode incrementar, na sua matriz energética, o uso de óleo oriundo de aves como alternativa aos combustíveis fósseis e à redução da dependência do óleo de soja para esse fim. O país dispõe de mais de 350 milhões de litros de óleo de frango por ano. Considerando a aplicação dos combustíveis alternativos para os motores a diesel, em máquinas agrícolas, o trabalho teve por objetivo avaliar o desempenho do motor de um trator agrícola de 53kW acoplado pela TDP em bancada dinamométrica, operando com biodiesel metílico de óleo de frango e misturas com óleo diesel, sendo: B5 (testemunha), B20, B40, B60, B80 e B100. Avaliaram-se a potência, o torque, a reserva de torque, o consumo de combustível, o consumo de energia e a eficiência térmica do motor. O ensaio foi instalado com delineamento inteiramente casualizado (DIC) em esquema fatorial com seis tratamentos. Os resultados foram submetidos à análise de variância e as médias ajustadas por equações de regressão. Foram observadas perdas na geração de potência e torque, aumento no consumo de combustível, redução do consumo energético e melhoria na eficiência térmica do motor, de acordo com o aumento da proporção de biodiesel na mistura.Brazil, the world third largest producer of biodiesel, and also the third largest producer of chicken, may increase the energy matrix, using oil derived from chicken, as an alternative to fossil fuels and reduce dependence on soybean oil for this purpose. The country can produce over 350 million liters of chicken oil per year. Considering the application of alternative fuels on diesel engines in agricultural machinery. The study aimed to evaluate the performance of a engine agricultural tractor with 53kW coupled by PTO in dynamometer bench operating with methyl biodiesel oil chicken and mix with diesel oil. Fuels B5 (reference), B20, B40, B60, B80 and B100 mixtures were used. The power, torque, torque reserve, fuel consumption, energy consumption and thermal efficiency of the engine were evaluated. The trial was conducted with a completely random design (CRD) in a factorial design with six treatment, which was held after the analysis of variance and adjusted means for the regression equations. Losses were observed in the generation of power and torque, increase in fuel consumption, reduction of energy consumption and improvement in engine thermal efficiency, according to the increasing proportion of biodiesel in the blend.

Considerando que o Brasil detém uma vasta gama de matérias-primas para produção de biodiesel, e também que há a possibilidade de produção em pequena escala, prima-se por estudos de cunho econômico a partir de metodologias de fácil execução. O objetivo do trabalho foi demonstrar uma metodologia e sua aplicação para avaliação dos custos inseridos dentro do processo produtivo e de utilização do biodiesel. A metodologia foi aplicada a biodieseis originários de óleo de soja, girassol, frango e sebo bovino, dos quais se avaliaram economicamente os custos fixos e variáveis para conversão química dos óleos e gorduras em ésteres metílicos, em uma planta de produção experimental. Os custos de produção para cada uma das quatro citadas são distintos em função do valor inicial por litro de cada uma. Também fora avaliado o custo específico e o consumo específico de cada um dos biodieseis, a fim de determinar a diferença em relação ao óleo diesel comercial. No estudo de caso, os resultados mostraram vantagens para o óleo diesel, tanto no custo quanto no consumo. Comparando-se os biodieseis, o de sebo bovino apresentou-se com o menor custo de produção e o menor consumo.Considering that Brazil has a wide range of raw materials for biodiesel production, and also the possibility of small scale production, there is a demand for economic methodology studies with easy implementation. The objective of this research was to demonstrate a methodology and its application to assess the costs within the production process and the biodiesel use. The methodology was applied to biodiesels originated from soybean oil, sunflower oil, chicken oil and beef tallow, which assessed the fixed and variable costs for chemical conversion of oils and fats into methyl esters in an experimental production plant. Production costs for each of the four mentioned esters are peculiar due to the initial value of each oil per liter. Also the specific cost and specific fuel consumption were evaluated for each biodiesel to determine the difference with the commercial diesel oil. The case study showed advantages for diesel oil, both in cost and consumption. Comparing the biodiesels, the beef tallow showed the lowest production costs and lower consumption.

Nos últimos anos, a área cultivada com pinhão-manso tem se expandido no Brasil, tendo em vista a sua utilização na produção de biocombustíveis. Um dos problemas enfrentados pelos produtores é a escassez de informações sobre a tolerância do pinhão-manso aos herbicidas registrados no Brasil. Diante disso, objetivou-se avaliar a tolerância de genótipos de pinhão-manso a herbicidas aplicados em pré-emergência da cultura. O experimento foi instalado em blocos casualizados, com quatro repetições, em esquema fatorial 3 x 6. O fator A foi composto pelos genótipos de pinhão-manso (Filomena, Gonçalo e Paraguaçu), e o fator B, pelos herbicidas (isoxaflutole, oxyfluorfen, sulfentrazone, pendimethalin e tebuthiuron) mais uma testemunha sem aplicação de herbicida. A intoxicação dos genótipos pelos herbicidas foi avaliada aos 19, 32, 40, 48, 56 e 64 dias após a aplicação dos tratamentos (DAT). Aos 64 DAT, avaliaram-se a altura, a área foliar e a massa seca da parte aérea das plantas. Constatou-se que os genótipos de pinhão-manso apresentaram níveis variáveis de tolerância aos herbicidas estudados. Isoxaflutole e tebuthiuron causaram severas injúrias aos genótipos avaliados e influenciaram negativamente todas as variáveis estudadas. Oxyfluorfen e pendimethalin mostraram-se mais seletivos, devendo ser avaliados em novos estudos a fim de serem recomendados para a cultura.In recent years, the areas cultivated with physic nut (Jatropha curcas) have expanded in Brazil, aiming at its use in biofuel production. However, one of the problems faced by the producers is the lack of studies on its tolerance to the herbicides registered in Brazil. The objective of this work was to evaluate the tolerance of physic nut genotypes to herbicides applied at pre-emergence. The experiment was arranged in a randomized block design, with four replications, in a factorial design, 3 x 6. Factor A was composed by the genotypes (Filomena, Gonçalo and Paraguaçu), and factor B by the herbicides (isoxaflutole, oxyfluorfen, sulfentrazone, pendimethalin and tebuthiuron), plus one non-treated control. Intoxication by the herbicides was evaluated at 19, 32, 40, 48, 56 and 64 days after treatments (DAT). Height, leaf area, and plant dry matter were evaluated at 64 DAT. It was verified that the jatropha genotypes have different tolerance to the herbicides studied. Isoxaflutole and tebuthiuron caused severe injuries to all genotypes and negatively affected all the variables evaluated. On the other hand, oxyfluorfen and pendimethalin proved to be selective to the crop and should be evaluated in further studies to be recommended to the crop.

The objective of this work was to compare phyllochron and leaf area on individual stalks of selected sugarcane (Saccharum officinarum) clones grown in a subtropical environment. A two-year field experiment was carried out in Santa Maria, RS, Brazil, during the 2007/2008 and 2008/2009 growing seasons. Three sugarcane clones were used: IAC 822045 (early), SP 711406 (median) and CB 4176 (late), in a complete randomized block design, with four replications. Expanded leaf and total leaf (tips) number were determined, and expanded leaf area was measured. The phyllochron (ºC day leaf-1) based on expanded and tip leaf number was estimated, using 10ºC as base temperature. Allometric relationships between individual area and number of expanded leaves were fitted. Phyllochron was analysed as a four-factor experiment: clone, growing season, phyllochron phase, and phyllochron type. The early clone had the greatest potential for growing in a subtropical climate because of higher leaf output and leaf area.O objetivo deste trabalho foi comparar o filocrono e a área foliar em colmos individuais de clones de cana-de-açúcar (Saccharum officinarum) cultivados em ambiente subtropical. Um experimento de campo foi conduzido em Santa Maria, RS, durante os anos agrícolas 2007/2008 e 2008/2009. Três clones de cana-de-açúcar foram usados: IAC 822045 (precoce), SP 711406 (médio) e CB 4176 (tardio), em blocos ao acaso, com quatro repetições. Foi medido o número de folhas expandidas e totais (pontas), além da área das folhas expandidas. O filocrono (ºC dia folha-1), baseado no número de folhas expandidas e totais, foi estimado utilizando 10ºC como temperatura base. Relações alométricas entre a área de folhas individual e o número de folhas expandidas foram ajustadas. O filocrono foi analisado considerando-se um experimento fatorial com quatro fatores: clone, ano agrícola, fase de filocrono e tipo de filocrono. O clone precoce tem maior potencial para cultivo em regiões subtropicais devido ao maior aparecimento de folhas e à maior área foliar.

O uso de combustíveis alternativos para diminuir a emissão de poluentes na atmosfera é uma tendência cada dia mais frequente, assim, faz-se necessária a investigação da eficiência destas misturas em proporções e condições diferentes. Ao diesel de petróleo, por forçade legislação, estão sendo adicionados 3% de biodiesel. Os valores da massa específica e do ponto de fulgor das amostras de diesel comercial analisadas, contendo 2 e 3% de biodiesel, mostraramsedentro dos parâmetros estabelecidos pela legislação brasileira. Os valores do índice de peróxido do biodiesel B100 aumentaram com o tempo de estocagem e com a presença de luz. Apesar disso, pela análise do perfil cromatográfico, não se verificaram alterações profundas na composição química do diesel B100 nas diferentes condições de armazenamento. O presente trabalho teve como objetivo analisar os combustíveis fósseis em misturas com biodiesel paraverificar a sua estabilidade e algumas propriedades físico-químicas.The use of alternative fuels to reduce pollutant emissions in the atmosphere is an increasingly frequent trend. Thus, it becomes necessary to research the efficiency of theses mixtures in various proportions and different conditions. To diesel oil, under the legislation, are being added 3% of biodiesel. The values of specific weight and the flashpoint of the samples of commercial diesel tested, containing 2 and 3% of biodiesel, were within the establishedparameters set by Brazilian legislation. The values of the peroxide index for B100 biodiesel increased with light and storage time. Nevertheless, analyzing the chromatographic profile, there were no considerable changes in the chemical composition of B100 diesel underdifferent conditions of storage. The aim of this work was examine fossil fuels in blends with biodiesel to determine their stability as well as some physical-chemical properties.

A dependência do petróleo e a poluição gerada pelo óleo diesel são as grandes desvantagens do uso deste combustível, o que vem estimulando a busca por fontes energéticas alternativas. Biodiesel é o combustível derivado de óleos vegetais ou de gordura animal que pode substituir total ou parcialmente o óleo diesel derivado de petróleo. Pode ser obtido por diferentes processos, como craqueamento, transesterificação ou esterificação, tendo glicerina como subproduto. A transesterificação é o método estimulado pelo Programa Nacional de Produção e Uso de Biodiesel no Brasil, consistindo na reação química de triglicerídios com álcoois (metanol ou etanol) na presença de um catalisador (NaOH). O objetivo desta revisão é discutir as vantagens e as desvantagens que a produção de biodiesel traz para a agricultura e o ambiente e a competição que pode ocorrer por recursos naturais entre a produção de alimentos e a de combustível. O biodiesel, além de ser obtido de fontes renováveis, tem como vantagens a menor emissão de gases poluentes e a menor persistência no solo. Entretanto, o custo de produção atualmente é maior e o balanço energético, apesar de variar com o sistema de produção utilizado, é menos favorável em relação ao óleo diesel. A maior demanda por grãos oleaginosos promoverá a utilização de mais espécies nos sistemas de produção em todo o país. Na Região Sul, tem sido dado maior enfoque às culturas da soja, girassol, canola e mamona. Esta última, incentivada em regiões de baixa disponibilidade hídrica, está sendo melhorada geneticamente para produção de biocombustível. Tem como desvantagem a presença de ricina, substância tóxica ao homem e que pode contaminar o ambiente. O girassol e a canola produzem óleos "nobres" para alimentação humana, com altos teores de ácidos graxos poliinsaturados. O biodiesel constitui-se em uma boa alternativa para a substituição parcial ou total do óleo diesel, mas as vantagens ambientais e agrícolas dependem de estudos pendentes em vários elos da cadeia produtiva.The petroleum dependence and the pollution generated by its use are the big disadvantages of this fuel, which demand look for another source of energy. Biodiesel is the fuel obtained from vegetables oils or animal fat, which can substitute petroleum diesel, total or partially. Three processes are possible to obtain biodiesel: cracking, tranesterfication or esterification, having glycerin as a derivate. The Brazilian National Program for Production and Use of Biodiesel stimulates the transesterification process, which is the chemical reaction of the triglycerides with alcohols (methanol or ethanol) using a catalyst (NaOH). The goal of this revision was to discuss the advantages and disadvantages that biodiesel production can bring for agriculture and environmental and the competition that could occur for natural resources between food and fuel production. The biodiesel obtained from renewable sources has as advantages the lower pollutant it gases emission and lower persistence in the soil. However, it has a higher cost production than petroleum diesel and the energy balance is less favourable, although it can vary with the system production used. The higher demand for oleaginous grains will increase the number of species used in crop production. In the south of Brazil, the species more stimulated are soybean, sunflower, canola and castor plant. Castor, that is an alternative for drought regions, is being genetically modified for fuel production, but it has the big disadvantage of ricin production, which is very poisonous for human and environment. Sunflower produces a very healthy oil for human use, with high levels of fat poliinsaturated acids. Biodiesel is a good alternative to substitute partial or totally petroleum diesel, but the environmental and agricultural advantages depend on studies in every link of its production chain.

Objetivou-se, neste trabalho avaliar o uso de misturas de biodiesel de girassol (Helianthus annuus L.) e diesel no desempenho de um motor de ignição por compressão, injeção direta. Os ensaios foram realizados em bancada dinamométrica utilizando-se as misturas B5, B10, B20 e B100 em comparação ao diesel (D). Foi analisado o desempenho do motor através da tomada de potência (TDP) com cada combustível, e analisado o óleo lubrificante do motor antes e após 96 horas de uso com B100. Os resultados obtidos foram: D (40,7 kW; 271 g/kW.h); B5 (40,3 kW; 271 g/kW.h); B10 (39,8 kW; 277 g/kW.h); B20 (40,0 kW; 277 g/kW.h) e B100 (39,8 kW; 291 g/kW.h). Concluiu-se que o uso das misturas B5, B10, B20 e B100 proporcionou redução de no máximo 2,2 % na potência na TDP e um aumento máximo de 7,3 %, no consumo específico de combustível. A análise do óleo lubrificante, antes e após o uso com B100, detectou alterações aceitáveis, sendo a viscosidade, a presença de água e o teor de ferro os parâmetros mais expressivamente alterados.This work aimed to evaluate the use of sunflower biodiesel (Helianthus annuus L.) blends in a CI engine, direct injection. The test procedure was carried out in a dynamometer bench that determined the performance of engine through power take-off (PTO) with use of diesel and sunflower biodiesel blends (B5, B10, B20 and B100). The lubricating oil was analyzed before and after period of 96 hours. The results were: D (40,7 kW; 271 g/kW.h); B5 (40,3 kW; 271 g/kW.h); B10 (39,8 kW; 277 g/kW.h); B20 (40,0 kW; 277 g/kW.h) e B100 (39,8 kW; 291 g/kW.h). One conclude that the use of blends B5, B10, B20 and B100 decreased the power of PTO max. 2,2% and increased the fuel consumption max. 7, 3%. The analysis of the lubricating oil before and after the use of B100 showed acceptable alterations and the viscosity, water content and level of iron were the most affected parameters.

Nos últimos trinta anos, a produção de etanol da cana-de-açúcar no Brasil avançou para 17 milhões de metros cúbicos, com perspectivas de atingir 35,7 milhões de metros cúbicos em 2012-2013. Esse crescimento ocorreu com grande aporte de tecnologia, por meio de geração, importação, adaptação e transferência interna. Uma análise das diferentes fases desse desenvolvimento é apresentada, com a evolução dos parâmetros tecnológicos e a grande competitividade atingida. A visão atual é que o setor poderá continuar a evoluir com melhorias contínuas ainda de modo importante, mas grandes "saltos" tecnológicos são possíveis mediante o desenvolvimento de tecnologias para o melhor uso da biomassa residual da cana (cerca de dois terços da biomassa total). Os estudos em curso indicam que a contribuição da cana para o suprimento de energia poderá ser muito superior (e diversificada) que a atual, e poderá ocorrer em paralelo com o desenvolvimento de biorrefinarias, levando a produtos de maior valor agregado.In the last 30 years, the production of ethanol from sugar cane in Brazil reached 17 million cubic meters and it is expected to achieve 35.7 million cubic meters by 2012-2013. This growth has taken place due to great technological support by means of production, imports, adaptations and internal transferences. An analysis of the different phases of this development, with the evolution of its technological parameters and the great competition of the sector, is presented in the article. Nowadays, foresights state that the sector may keep evolving with continuous improvements, but sudden technological boosts are also possible through the development of technologies directed towards a better use of the residual biomass of sugar cane (which represents about two thirds of the total biomass). Studies in progress indicate that the sugar cane contribution to energy supply may be superior and more diversified than the current one. They also affirm that this may happen together with bio-refinery development, which will result in products of higher aggregate values.

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e 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.)

This research evaluated the performance of a diesel engine in an agricultural tractor, using Diesel S500 (B5) and mixture with 3% (ED3), 6% (ED6), 9% (ED9), 12% (ED12) and 15% (ED15) of hydrous ethanol. Variables evaluated were the power, torque, specific fuel consumption, torque reserve, speed reserve and elasticity index of engine. Results indicated that using B5 and ED3 the values of torque and engine power not differ, in addition, with the ED3 the fuel consumption was lower than 5.92%. Using ED12, power has reduced in 2.97%, compared with B5, while their fuel consumption had no difference. With ED15, the power was lower 6.30% and the fuel consumption increase 3.77%, both compared with B5. Torque reserve value was increased with increasing the ethanol content in B5, reducing the speed reserve and elasticity index of engine. Ethanol in Diesel S500 (B5) can be used as an alternative fuel in agricultural tractor engines without presenting high changes in the performance, since the ethanol content is at low percentages, up to 12%. [ABSTRACT FROM AUTHOR]

Copyright of Acta Scientiarum: Technology is the property of Universidade Estadual de Maringa 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 Scientiarum: Technology is the property of Universidade Estadual de Maringa 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 root knot nematode (RKN), Meloidogyne incognita, is widespread worldwide and a major pathogen of several cultivated crops. The use of resistant genotypes is the most effective and environmentally sound way to manage RKN. In this study, we screened 16 selected sweet potato cultivars including Amanda, Bárbara, Beatriz, Beauregard, Brazlândia Branca, Brazlândia Rosada, Brazlândia Roxa, BRS Amélia, BRS Cuia, BRS Rubissol, Carolina Vitória, Duda, Júlia, Marcela, PA-26/2009, and Princesa obtained from Embrapa and Universidade Federal do Tocantins' germplasm bank. Studies were conducted under greenhouse and field conditions and the agronomic performance of the cultivars was evaluated in a nematode and soilborne insect-infested field. All 16 sweet potato cultivars tested were rated as resistant to this nematode both under greenhouse and field conditions with reproduction factors < 1. In the field infested with M. incognita, sweet potato cultivars Duda, BRS Amélia, Beauregard, Brazlândia Rosada, and Brazlândia Roxa stood out as superior cultivars, with average yield ranging from 26 to 47 tons per ha. Overall, most cultivars exhibited a fusiform to near fusiform root shape, a good characteristic for the market, and were moderately affected by insects (attack incidence 1 to 30%). As global demand for energy continues to rise, selecting new cultivars of sweet potatoes with increased resistance to nematode diseases and with high yield will be important for food security and biofuel production. [ABSTRACT FROM AUTHOR]

This research aims to characterize the production of briquettes from four different biomasses. We used residues such as Eucalyptus sp sawdust, Pinus sp sawdust , sugarcane bagasse (Saccharum officinarum L.) and sugarcane straw. The residues were treated to obtain 12% moisture content and particle size less than 1.70 mm. We produced 15 briquettes for each treatment. The pressure used was 1250 kgf.cm-2 for 30 seconds. The briquettes obtained densities ranged from 0.88 to 1.11 g.cm-3 . This represented a range of 5 to 14 times less volume occupancy for the same amount of mass. The high heating value (HHV) was 19,180 J.kg-1 and 20,315 J.kg-1 for eucalyptus and pine sawdust respectively. The HHV for the bagasse was 18,541 J.kg-1 and for straw was 15,628 J.kg-1 . The straw presented an ash content of 12%. The expansions of the treatments ranged 4 to 9% and mechanical resistances ranging from 1,215 MPa to 0,270 MPa. All briquettes were resistant to a higher stacking to 10 m high. The methods can help to decrease the space of storage and transport. [ABSTRACT FROM AUTHOR]