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Drape optimization in woven composites manufacture.
This paper addresses the optimisation of forming in manufacturing of composites.
A simplified finite element model of draping is developed and implemented. The
model incorporates the non-linear shear response of textiles and wrinkling due
to buckling of tows. The model is validated against experimental results and it
is concluded that it reproduces successfully the most important features of the
process. The simple character of the model results in low computational times
that allow its use within an optimisation procedure. A genetic algorithm is used
to solve the optimisation problem of minimising the wrinkling in the formed
component by selecting a suitable holding force distribution. The effect of
regularisation is investigated and the L-curve is used to select a
regularisation parameter value. Optimised designs resulting from the inversion
procedure have significantly lower wrinkling than uniform holding force
profiles, while regularisation allows force gradients to be kept relatively low
so that suggested process designs are feasible
Purple corn (zea mays l.) pericarp hydroalcoholic extracts obtained by conventional processes at atmospheric pressure and by processes at high pressure
Extracts of Peruvian purple corn pericarp (Zea mays L.) were obtained: (1) via supercritical fluid extraction with CO2 as solvent and EtOH-H2O (70:30, v/v) as co-solvent, (2) via pressurized liquid extraction (PLE) with EtOH-H2O (70:30, v/v) and, (3) via two conventional extraction processes, stirred vessel and Soxhlet. The extraction yields and extract compositions were compared to each other. The parameters measured were the point-to-point extraction yield, the global extraction yield and composition of extracts regarding contents of total phenolics, total flavonoids, total anthocyanins and specific anthocyanins such as cyanidin-3-glucoside, peonidin-3-glucoside and pelargonidin-3-glucoside. Antioxidant activity by DPPH and in vitro antiproliferative activity were also evaluated considering seven cancer cell lines. High yields and higher contents of phenolic compounds, accompanied by a high antioxidant activity at 50 °C, were obtained for supercritical extraction at 60 °C. Antioxidant activity showed good correlation with the content of phenolic compounds, but there was no antiproliferative activity37237248COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPSem informação12/51317-
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