The discontinuous contour of a wing with conventional flaps diminishes the aerodynamic performance of an aircraft. A wing with a continuous contour does not experience extreme flow stream fluctuations during flight, and consequently has good aerodynamic characteristics. In this study, a morphing flap using shape memory alloy actuators is proposed, designed and fabricated, and its aerodynamic characteristics are investigated using aerodynamic analyses and wind tunnel tests. The ribs of the morphing flap are designed and fabricated with multiple elements joined together in a way that allows relative rotations of adjacent elements and forms a smooth contour of the morphing flap. The aerodynamic analyses of this multiple-element morphing-flap wing are performed using XFLR pro; its aerodynamic performance is compared with that of a mechanicalflap wing, and is measured through wind-tunnel tests.

The long-chained perfluoroalkyl acids (PFAAs), perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), are a potential exposure risk in the environment, specifically for humans due to high levels of bioaccumulation, persistence, and toxicity. In the current study, the plant uptake factors (PUFs) of spinach and Welsh onion were investigated on the three different concentration levels of PFOA and PFOS in soil. Spinach and Welsh onion were divided into three residue groups, a control group and two levels of PFOA and PFOS. The PFAAs spiked soils were aged for six months and the extractable residue of PFOS in the aged soil was reduced to 30-59% of the initial spiked concentrations for PFOS, while PFOA showed almost the same initial spiked concentrations. The PUFs for PFOA and PFOS were 0.111-2.821 and 0.047-3.175 for spinach, and 0.203-0.738 and 0.035-0.181 for Welsh onion, respectively. The highest PUF values in both vegetable were displayed when the residual concentration of PFAAs were part-per-billion (ppb) or sub-ppb in soil.

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