Color and chemical composition and of green corn produced under organic and conventional conditions.

The present study aimed to evaluate the chemical properties of green corn, grown in both organic and conventional farming systems, using a completely randomized factorial design. Four corn varieties (AG 1051, BR 106, SWB 551 and VIVI) of green corn kernels were evaluated for color, proximate composition, total calories, carotenoids and bioactive amines. The farming system affected some chemical and physical characteristics of green corn, but this effect was dependent upon variety. In general, organic green corn kernels were reddish (a* color component) and had higher levels of ?-carotene compared to the conventional ones, suggesting that these characteristics are related. Moreover, organic green corn had higher levels of total carbohydrates and total energy compared to conventional varieties. On the other hand, crude fiber levels were higher in conventional grains - an unexpected result that deserves further investigation. Finally, the levels of cadaverine and spermine bioactive amines were not affected either by the corn variety or by the farming system. Avaliaram-se as características químicas de milho verde cultivado em sistemas de produção orgânico e convencional. Utilizou-se um delineamento inteiramente casualizado em esquema fatorial 4 × 2, com quatro cultivares (AG 1051, BR 106, SWB 551 e VIVI) em dois sistemas de cultivo (orgânico e convencional), duas ou três repetições. Os parâmetros físico-químicos analisados foram cor, composição centesimal, valor energético total, teor de carotenoides e aminas bioativas. O sistema de produção tem influência sobre as características químicas do milho verde, mas esse efeito é na maioria dos casos específico para cada cultivar. Pode-se generalizar que os grãos advindos de culturas orgânicas apresentam tom mais avermelhado (a*) e maiores teores de β-caroteno, sendo possível que esses dois atributos estejam relacionados. Além disso, milho verde orgânico tem maior teor de carboidratos e teor energético. Em contrapartida, o teor de fibras foi mais alto no cultivo convencional, e esse dado inesperado merece maior investigação. Os teores das aminas bioativas acadaverina e espermina não foram afetados pelo sistema de produção ou cultivar

Synergistic effect of fibres on the physical, mechanical, and microstructural properties of aerogel-based thermal insulating renders

There is an increasing demand for highly efficient thermal insulating materials in buildings. This study presents a novel solution incorporating nanomaterials, such as silica aerogel, which can achieve low thermal conductivity values (below 0.030 W m-1 K-1) in renders. A key challenge of using aerogels is their low mechanical strength and high capillary water absorption. Here we describe a novel approach employing fibres which mitigates against some key properties which are decreased as a consequence of using aerogel. The incorporation of aramid (0.50%), sisal (0.10%), and biomass (0.10%) fibres (by total volume) was evaluated experimentally in terms of physical, mechanical, and microstructural properties. A synergistic effect between the fibres and aerogel increased mechanical resistance and a reduction in the capillary water absorption, when compared to the reference render (without fibres), whilst maintaining the low thermal conductivity. However, these properties depended significantly on whether the fibres were synthetic or organic. This study is important as it demonstrates that aerogel-based fibre-enhanced thermal renders can contribute to higher energy efficiency in both new construction and retrofitting. The use of these materials will have a direct positive impact on addressing the climate crisis

Synergistic effect of fibres on the physical, mechanical, and microstructural properties of aerogel-based thermal insulating renders

There is an increasing demand for highly efficient thermal insulating materials in buildings. This study presents a novel solution incorporating nanomaterials, such as silica aerogel, which can achieve low thermal conductivity values (below 0.030 W m-1 K-1) in renders. A key challenge of using aerogels is their low mechanical strength and high capillary water absorption. Here we describe a novel approach employing fibres which mitigates against some key properties which are decreased as a consequence of using aerogel. The incorporation of aramid (0.50%), sisal (0.10%), and biomass (0.10%) fibres (by total volume) was evaluated experimentally in terms of physical, mechanical, and microstructural properties. A synergistic effect between the fibres and aerogel increased mechanical resistance and a reduction in the capillary water absorption, when compared to the reference render (without fibres), whilst maintaining the low thermal conductivity. However, these properties depended significantly on whether the fibres were synthetic or organic. This study is important as it demonstrates that aerogel-based fibre-enhanced thermal renders can contribute to higher energy efficiency in both new construction and retrofitting. The use of these materials will have a direct positive impact on addressing the climate crisis

Analise Dinâmica do Desempenho Energético de um Envidraçado Termocrómico em Diferentes Zonas Climáticas de Portugal

Highly glazed facades are usually responsible for significant heat exchanges that increase climatization energy needs. Thermochromic glazing, an innovative glazing solution, can autonomous and reversibly alter its properties depending on the temperature of the thermochromic layer laminated between the external glass panes, promoting the reduction of thermal gains and the increase of indoor comfort and energy efficiency. This study aims at assessing the energy performance of a thermochromic glazing against a conventional static glazing with and without a reflective solar control film, considering an individual office room oriented southeast as case study. A dynamic simulation, previously calibrated with experimental data, was used to compute the monthly and yearly energy needs (heating and cooling) and energy use (climatization and artificial lighting) with the different glazing solutions installed in the cities of Braganza, Lisbon and Faro, representative of different climate zones of Portugal. A reduction up to 65% of the cooling energy needs was obtained with the thermochromic glazing. The dynamic behaviour of the thermochromic glazing reduced indoor daylight levels, consequently increasing artificial lighting energy use. However, it was possible to achieve a reduction up to 50% of the total energy use (climatization and artificial lighting) with the dynamic glazing.Fachadas de edifícios com grandes áreas envidraçadas tendem a promover trocas térmicas significativas que resultam em necessidades energéticas para climatização elevadas. Os envidraçados termocrómicos podem alterar de forma autónoma e reversível as suas propriedades térmicas e óticas dependendo da sua temperatura, promovendo a mitigação de ganhos térmicos e a melhoria de condições de conforto interior e eficiência energética. Este estudo tem como objetivo analisar o desempenho energético de um envidraçado termocrómico instalado num gabinete orientado a sudeste. Para esse fim, foi utilizado um modelo de simulação dinâmica, anteriormente calibrado com dados experimentais, para avaliar o desempenho energético anual do vidro termocrómico comparativamente ao de um envidraçado convencional incolor com e sem uma película refletora de controlo solar. As necessidades energéticas (aquecimento e arrefecimento) e o consumo energético (aquecimento, arrefecimento e iluminação artificial) foram obtidos para as diferentes soluções de envidraçados nas cidades de Bragança, Lisboa e Faro, representativas de diferentes zonas climáticas de Portugal. Com o envidraçado termocrómico obteve-se uma redução significativa, até 65%, das necessidades energéticas para arrefecimento. Apesar do comportamento dinâmico do envidraçado termocrómico e da diminuição das condições de iluminação natural do gabinete, foi possível obter uma redução do consumo anual energético total até 50%

Decolorization and detoxification of industrial wastewater containing indigo carmine by Aspergillus niger AN400 in sequential reactors

Effluents from the textile industry are an active problem in the sector and one of the worlds main environmental problems. The conventional treatments applied are not always efficient in terms of compliance with legislation, and, in many cases, the efficiency of treatment is guaranteed by the enormous energy expenditure involved, camouflaging the momentary problem and not effectively treating it. In this work, batch reactors with immobilized biomass of Aspergillus niger AN400 were arranged in series for the treatment of real textile wastewater containing approximately 20 mg/L of indigo carmine. Sucrose was added as a co-substrate in concentrations of 1 g/L and 0.5 g/L, in the first and second reactors, respectively, over 19 cycles of 48 h. The highest decolorization rate in the system was (93 ± 4) %, with the largest amount removed in the first reactor (90 ± 6) %, occurring mainly by biological means. The production of aromatic by-products from the initial degradation of the dye molecule was reflected in the lower removal efficiency of dissolved organic matter: 52% in the first reactor, and 25% in the second reactor. The number of colonies of fungi was higher than that of bacteria, 2.24:1 and 2.44:1 in the first and second reactors, respectively. The treated effluent in the system showed less toxicity than the raw effluent, and this demonstrates the potential of this technology in the treatment of textile effluents containing indigo carmine.info:eu-repo/semantics/publishedVersio

Métodos analíticos para a determinação de diversos elementos em tortas de filtro rotativo

This paper describe the analytical methods employed for the determination of copper, zinc, iron, manganese, cobalt, molybdenum, organic and organic phosphorus, silicon, organic mater and organic carbon in filter mud.Neste trabalho são descritos os métodos analíticos empregados para a determinação de micronutrientes (Fe, Mn, Cu, Zn e Mo), cobalto, fósforo orgânico e inorgânico, silica, matéria orgânica e carbono orgânico em torta de filtro rotativo. São apresentadas as marchas analíticas preconizadas e os resultados obtidos nas determinações efetuadas em vinte e duas amostras do material