A lógica produtiva em produtores de leite micaelenses

Seminário Agricultura e Ambiente: Conflito de lógicas produtivas?, Departamento de Ciências Agrárias, Universidade dos Açores, 27 de novembro 2014. ISBN 978- 972-8612-94-8 (Atas em CD)A produção de leite, nos Açores, representa a maior atividade agrícola regional e contribui com cerca de 1/3 da produção de leite nacional. Na região, a ilha de S. Miguel contribui com mais de metade da produção de leite. Para verificar se a lógica produtiva das explorações micaelenses se coaduna com a viabilidade económica e com os níveis de eficiência técnica das explorações leiteiras, utilizámos a base de dados da AASM (Almeida, 2012), que é constituída por 91 explorações agropecuárias (produção de leite) inscritas no Contraste Leiteiro e com contabilidade organizada, em 2010. A lógica produtiva foi avaliada pelo nível de intensificação das explorações leiteiras, que foi medida pela carga animal por hectare. Com base numa nova organização dos dados da AASM, confrontaram-se os níveis de eficiência e viabilidade e competitividade económica com os resultados de explorações leiteiras obtidos por Silva e Almeida (2014) e Almeida e Silva (2013-a; 2013-b). Em termos gerais, constata-se que o valor de eficiência técnica das explorações leiteiras a rendimentos constantes e que o número explorações eficientes a nível técnico é mais elevado no intervalo inferior a 1,4 animais por hectare, ou seja, a extensificação potencia melhores níveis de eficiência técnica. Na viabilidade e competitividade económica das explorações leiteiras, verifica-se que, de um modo geral, ao maior nível de intensificação, corresponde a maior a produção de leite e rendimento. No entanto, a política agrícola, em vigor nos Açores, promove a lógica produtiva dos produtores de leite, em que o aumento da produção de leite não acompanha a lógica da eficiência técnica. A decisão do produtor de leite micaelense é mais condicionada pela lógica económica que pela lógica ambiental.info:eu-repo/semantics/publishedVersio

Efeito de poleiros artificiais na chuva de sementes em áreas de ocorrência da floresta estacional semidecidual, Fênix, PR.

Resumo

Enquadramento energético do sector residencial português

Portugal não possui reservas de energias fósseis, pelo que importa grande parte dos recursos energéticos que consome. Nos últimos anos tem sido feita uma aposta na instalação de sistemas de produção de energia a partir de energias renováveis no sentido de reduzir a dependência energética nacional. Contudo, os níveis de dependência, em 2010, ainda eram muito elevados principalmente devido à importação de petróleo. O sector residencial é o que apresenta o terceiro maior consumo energético. Tendo-se verificado nos últimos anos um aumento crescente dos consumos, em especial de eletricidade. Através da avaliação da tendência de evolução do consumo energético das habitações, é possível determinar qual a melhor forma de reduzir esses consumos aquando da reabilitação energética dos edifícios. O estudo apresentado tem por objetivo analisar os consumos energéticos do sector residencial, de forma a saber em que fatores intervir para aumentar a eficiência energética do parque habitacional Português

Energy rehabilitation of Portuguese residential building stock through its transformation into NZEB

The first global oil crisis, led the European Union to start the necessary procedures in order to control and reduce the energy consumption of buildings. In Europe the energy consumption of residential buildings increased since 1990 until 2003 1.3% per year and it is expected that, by 2050, the energy consumption of buildings will have increased by 40%. According to the EPBD-recast all member states should adopt the necessary measures so that buildings become highly efficient - nearly Zero Energy Buildings (nZEB’s). Nevertheless, quantitative standards are not appointed, so each member state should establish the minimum requirements for energy performance in buildings attending to the local conditions. However before establishing these requirements it is necessary to evaluate the building stock and its energy efficiency. As most of the Portuguese residential buildings are old and degraded an opportunity arises for the energy rehabilitation of the building stock, implementing EPBD-recast principles, making it more energy efficient and comfortable. The aim of this study was to describe the current conditions of the building stock in order to identify whether there are suitable conditions for energy rehabilitation of buildings. The analysis performed showed that although there are a significant potential for building energy rehabilitation, there are also some constraints, namely the lack of credit and loans financing of banks

Origin of the Significant Impact of Ta on the Creep Resistance of FeCrNi Alloys

Heat resistant FeCrNi alloys are widely used in the petrochemical industry because they exhibit a unique combination of creep and oxidation resistance at temperatures exceeding 900$^\circ$C. Their creep properties are often optimized by micro-additions of carbide forming elements. In the present work, the influence of Ta micro-additions has been experimentally investigated both on as-cast and aged microstructures to understand the origin of the significant impact of this element on the creep resistance. Calculations with thermocal software were also carried out to support experimental data. It is shown that a small addition of Ta is beneficial as it increases the volume fraction of stable MC carbides. We demonstrate also that additions of Ta may have a dramatic effect on the thermal stability of microstructures. This is attributed to a smaller equilibrium volume fraction of M23C6 and more pronounced heterogeneous precipitation at MC/matrix interfaces. The influence on the creep properties in then discussed

Continuous beer fermentation with yeast immobilized on alternative cheap carriers and sensorial evaluation of the final product

Continuous beer fermentation offers a wide range of advantages, mostly of economic nature over the traditional batch process. However, due to increased complexity of operation comparing to batch process, flavor problems, risk of contamination, yeast viability, carrier price and inconvenience of immobilization, the continuous beer fermentation has found few practical applications so far. The carrier cost represents a significant part of the investment costs and therefore the need for a cheap support material easy to regenerate is still relevant. This work deals with a complete continuous fermentation system for beer fermentation and maturation consisting of an airlift and a packed-bed reactor containing brewing yeast immobilized on spent grains and corncobs, respectively. The objective of this study was to verify the long-term performance of the system and the suitability of these new cellulose-based carrier materials made from brewing and agricultural by-products. Further the influence of feed rate and aeration rate on bioreactors fermentation performance, immobilized biomass load, ethanol production and flavor profile of both green and maturated beer was followed. The influence of process parameters on sensorial quality of beer has been studied by physicochemical methods as well as by sensorial analysis (acceptance and description tests) carried out by both consumers and experienced tasters. This work clearly demonstrated the technological feasibility of the continuous brewing based on yeast immobilization on cheap alternative carriers (spent grains, corncobs) for continuous production of a beer with a balanced flavor profile.Fundação para a Ciência e a Tecnologia (FCT) - SFRH / BPD / 3541 / 2000.Fundação de Amparo a Pesquisa do Estado de São Paulo (FAPESP) - Proc. 00/12767-4.Unicer SA.

Influence of temperature on continuous high gravity brewing with yeasts immobilized on spent grains

Flavor compounds’ formation and fermentative parameters of continuous high gravity brewing with yeasts immobilized on spent grains were evaluated at three different temperatures (7, 10 and 15 °C). The assays were performed in a bubble column reactor at constant dilution rate (0.05 h−1) and total gas flow rate (240 ml/min of CO2 and 10 ml/min of air), with high-gravity all-malt wort (15°Plato). The results revealed that as the fermentation temperature was increased from 7 to 15 °C, the apparent and real degrees of fermentation, rate of extract consumption, ethanol volumetric productivity and consumption of free amino nitrogen (FAN) increased. In addition, beer produced at 15 °C presented a higher alcohols to esters ratio (2.2–2.4:1) similar to the optimum values described in the literature. It was thus concluded that primary high-gravity (15°Plato) all-malt wort fermentation by continuous process with yeasts immobilized on spent grains, can be carried out with a good performance at 15 °C.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq).Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP).Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Optimization of ethanol production from cheese whey powder by Kluyveromyces fragilis using factorial design and response surface methodology

The individual and combined effects of initial lactose concentration, temperature and inoculum concentration on ethanol production from cheese whey powder by Kluyveromyces fragilis were investigated. A 2 3 full-factorial central composite design (CCD) and response surface methodology (RSM) were employed in order to determine the optima conditions that maximize the ethanol production. Statistical analysis of results showed that, in the range studied, only the initial lactose concentration had a significant effect on ethanol production. Response surface data showed maximum ethanol production at inoculum concentration between 1 and 3 g/L and temperature between 25 and 35ºC when the initial lactose concentration was 150 g/L.CAPES/Grices - BEX2150/07-7

Optimal fermentation conditions for maximizing the ethanol production by Kluyveromyces fragilisfrom cheese whey powder

Cheese whey powder (CWP) is an attractive raw material for ethanol production since it is a dried and concentrated form of CW and contains lactose in addition to nitrogen, phosphate and other essential nutrients. In the present work, deproteinized CWP was utilized as fermentation medium for ethanol production by Kluyveromyces fragilis. The individual and combined effects of initial lactose concentration (50-150 kg m-3), temperature (25-35 ºC) and inoculum concentration (1-3 kg m-3) were investigated through a 23 full factorial central composite design, and the optimal conditions for maximizing the ethanol production were determined. According to the statistical analysis, in the studied range of values, only the initial lactose concentration had a significant effect on ethanol production, resulting in higher product formation as the initial substrate concentration was increased. Assays with initial lactose concentration varying from 150 to 250 kg m-3 were thus performed and revealed that the use of 200 kg m-3 initial lactose concentration, inoculum concentration of 1 kg m-3 and temperature of 35 ºC were the best conditions for maximizing the ethanol production from CWP solution. Under these conditions, 80.95 kg m-3 of ethanol was obtained after 44 h of fermentation.The authors acknowledge the financial support from "CAPES/Grices (BEX2150/07-7) and Lactogal for supplying cheese whey powder