1,043 research outputs found
Decomposição de leite em forno de microondas com radiação focalizada - uma visão alternativa: adição da amostra ao reagente pré-aquecido.
Aplicação da análise exploratória para avaliação da diferenciação de alimentos produzidos organicamente e convencionalmente.
Phosphorous removal from water by polyolefins: effect of Al2O3 addition
Phosphorus is the main nutrient responsible for eutrophication of aquatic ecosystems,
therefore it is important to develop new processes to remove phosphorus that avoid the
formation of precipitates. Polyolefins with and without prior activation with aluminum
oxide (Al2O3), processed as flat plates, were investigated for phosphate removal from
an aqueous solution. The maximum amount of phosphorus removal was 0.042
μgP/cm2 for PE (polyethylene), 0.049 μgP/cm2 for PE-g-MA (polyethylene grafted with
maleic anhydride), and 0.071 μgP/cm2 for PE-g-MAe (PE-g-MA enriched in MA).
Increasing polyolefins’ polarity did not result in a significant increase in phosphate
removal. Activated polyolefins with Al2O3 presented maximum amounts of phosphorus
removal of 0.863 μgP/cm2 for PE, 0.948 μgP/cm2 for PE-g-MA, and 0.884 μgP/cm2 for
PE-g-MAe. As expected, addition of Al2O3 considerably increased phosphate removal.
In kinetic experiments carried out with polyolefins activated with Al2O3 during 3 months
a very high percentage of phosphorus removal was obtained for (> 90 %) as well as a
very low remaining phosphorus concentration in solution (< 10 μgP/L).
As a conclusion, polyolefins activated with Al2O3 effectively removed phosphorous from
aqueous solutions with low concentrations which indicate that this material might be
used for in-situ remediation of eutrophic waters. The possibility to recover the material
after use to recycle phosphate and the absence of precipitates’ formation are two major
advantages of this process.Fundação para a Ciência e a Tecnologia (FCT) - SFRH/BD/39085/2007
Biodegradable nanocomposite for food packaging application
Biodegradable poly(lactic) acid (PLA)/clay nanocomposites were investigated to be used as food packaging material. Several
techniques were used, rheology, mechanical, gel permeation chromatography (GPC), contact and biodegradability tests, to
characterize the developed materials.
The addition of organoclay improved PLA mechanical and biodegradable properties. Food contact test showed that the
nanocomposites are able to be used as food packaging materials
Incorporating tool deformation in the design of extrusion dies for complex hollow profiles
The potential of OpenFOAM to design extrusion dies, incorporating the Fluid Structure Interaction (FSI)Fundação para a Ciência e a Tecnologia (FCT) - FCOMP-01-0124-FEDER-015126 (Refª. FCT PTDC/EMEMFE/
113988/2009), FCOMP-01-0124-FEDER-010190 (Refª. FCT PTDC/EME-FME/102729/2008)
and PEst-C/CTM/LA0025/2011 (Strategic Project - LA 25 – 2011-2012), SFRH/BD43632/2008, FCT-SFRH/ BPD/ 77467/ 201
Microwave assisted decomposition of protein-and fath rich samples under mild acidic conditions.
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