Sustainable development aspects of biodiesel production and application in Brazil

Concerns about climate change effects have prompted many countries to search for solutions to reduce fossil fuel consumption. In the last few years biodiesel production has gained world attention, as it is seen as a sustainable and renewable energy source. Biodiesel is a natural substitute for diesel oil, and can be obtained from different oleaginous plants. However, there are worries about devastation of forests and biodiversity-rich areas to produce biodiesel. Even considering biodiesel as a promising solution, the impacts of its production must be carefully evaluated. This work examines the Brazilian scenario for biodiesel production and use as an automotive fuel. Native and adapted oleaginous in many Brazilian regions and their potentiality for biodiesel production are presented. Experimental results of hydrocarbons (HC), carbon monoxide (CO), and carbon dioxide (CO2) emissions from a diesel power generator fuelled by blends of diesel oil and castor oil or soybean biodiesel are also presented

Further developments on biodiesel production and applications in brazil

Environmental concerns have motivated many countries to search for solutions to reduce fossil fuel consumption. In the last few years, biodiesel has attracted attention as a possible sustainable and renewable energy source to substitute diesel oil. Biodiesel can be produced from different oleaginous plants, but there are worries about food competition and forests and biodiversity-rich areas devastation to produce biodiesel. Even considering biodiesel as a promising solution, its production impacts must be carefully evaluated. This work examines the Brazilian prospects for biodiesel production and use as an engine fuel for automotive propulsion and power generation. The potential for biodiesel production of many native and adapted oleaginous plants in Brazilian territory is discussed. Experimental results of hydrocarbons, carbon monoxide, and carbon dioxide emis-sions from a diesel power generator fuelled by blends of diesel oil and castor oil or soybean biodiesel are also presented

Quasars: What turns them off?

(Abridged) We explore the idea that the anti-hierarchical turn-off observed in the quasar population arises from self-regulating feedback, via an outflow mechanism. Using a detailed hydrodynamic simulation we calculate the luminosity function of quasars down to a redshift of z=1 in a large, cosmologically representative volume. Outflows are included explicitly by tracking halo mergers and driving shocks into the surrounding intergalactic medium. Our results are in excellent agreement with measurements of the spatial distribution of quasars, and we detect an intriguing excess of galaxy-quasar pairs at very short separations. We also reproduce the anti-hierarchical turnoff in the quasar luminosity function, however, the magnitude of the turn-off falls short of that observed as well as that predicted by analogous semi-analytic models. The difference can be traced to the treatment of gas heating within galaxies. The simulated galaxy cluster L_X-T relationship is close to that observed for z~1 clusters, but the simulated galaxy groups at z=1 are significantly perturbed by quasar outflows, suggesting that measurements of X-ray emission in high-redshift groups could well be a "smoking gun" for the AGN heating hypothesis.Comment: 16 pages, 11 figures, submitted to ApJ, comments welcome

Correlações e análises do coeficiente-vetor (Path-coefficient em linhagens endogamicas de milho (Zea mays L.).

Objetivou-se determinar as inter-relacoes entre sete caracteres em progenies de milho, obtida de cruzamentos entre linhagens "dent" e "flint" com os compostos "Flint B" e "Dent B", respectivamente. Encontraram-se correlacoes significativas para peso de graos com alturas de planta e espiga e com prolificidade, indicando a importancia destes caracteres no aumento da produtividade do milho, em condicoes brasileiras. Prolificidade e peso de 50 graos correlacionaram-se negativa e significativamente. Observou-se uma correlacao significativa e positiva entre numero de dias ate o florescimento e porcentagem de umidade nos graos, mostrando que precocidade esta diretamente ligada com maturacao fisiologica, nestes materiais. Encontraram-se pequenas diferencas de valores de coeficientes vetor (path-coefficient) para as progenies dos cruzamentos contrastantes entre linhagens e compostos, possivelmente devido a erros de amostragens ou a variabilidade genetica entre estas progenies. Os valores elevados e positivo de coeficiente-vetor encontrados para alguns caracteres, como prolificidade e peso de 50 graos, mostraram uma influencia direta e significativa destes caracteres no peso de graos

Comparação entre essências florestais nativas e exóticas em Quedas do Iguacu, PR - resultados preliminares.

bitstream/item/215524/1/circ-tec15.pd

General and specific combinig ability for yield in a diallel cross among 18 maize populations (Zea mays L.).

A study was carried out no diallel crosses among 18 maize populations. An analysis was conducted on ear weight data using Grigging's Method 2, Model I to determine general and specific combinig ability effects. General combining ability (GCA) was found to be significant but specific combinig ability (SCA) was not. Both location x GCA and location x SCA interactions were found to be significant. The results showed that populations CMS 06 and CMS 05 have the highest GCA effects. The cross (CMS 07 x CMS 10) gave the highest SCA effects