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621.
In this work, we first present a method to experimentally capture the free flight of a beetle (Allomyrina dichotoma), which is not an active flyer. The beetle is suspended in the air by a hanger to induce the free flight. This flight is filmed using two high-speed cameras. The high speed images are then examined to obtain flapping angle, flapping frequency, and wing rotation of the hind wing. The acquired data of beetle free flight are used to design a motor-driven flapper that can approximately mimic the beetle in terms of size, flapping frequency and wing kinematics. The flapper can create a large flapping angle over 140° with a large passive wing rotation angle. Even though the flapping frequency of the flapper is not high enough compared to that of a real beetle due to the limited motor torque, the flapper could produce positive average vertical force. This work will provide important experience for future development of a beetle-mimicking Flapping-Wing Micro Air Vehicle (FWMAV). 相似文献
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Hee-Guk Byun Tae-Kil Eom Won-Kyo Jung Se-Kwon Kim 《Biotechnology and Bioprocess Engineering》2007,12(5):484-490
In this study, fish oil was hydrolyzed by lipase in a fish oil-in-water emulsion system in an effort to improve the functional
properties of fish oil. Lipase activity was found to depend on the quality of the water/fish oil interface area. We selected
several suitable emulsifiers, and their emulsifying activities were evaluated under a variety of conditions, including concentration,
water-oil ratios, pH values, and temperature. Among the selected emulsifiers, the emulsifying activity of gelatin was higher
than those of carboxymethyl chitin (CM-chitin), bovine serum albumin, and Tween-20, all of which are commercial emulsificers
Moreover, the emulsifying activity of the gelatin solution was the highest at 0.5%, and was reduced with increasing concentrations
of above 1%. The optimal water-oil ratio, pH, and temperature conditions were 40% (w/v), pH 8.0 and 40°C, respectively. Under
these conditions, the emulsifying activity of gelatin solution was 86%. The emulsion structure of the gelatin solution was
characterized by high density and small particle size. The degree of sardine oil hydrolysis in the emulsion system was 50%
higher than that of the non-emulsion system. The lipid species of the lipase-prepared sardine oil hydrolysates were identified
as triacylglycerol, 1,3- and 1,2-diacylglycerol, monoacylglycerol, and fatty acid. 相似文献
626.
Organic Solar Cells: On‐Fabrication Solid‐State N‐Doping of Graphene by an Electron‐Transporting Metal Oxide Layer for Efficient Inverted Organic Solar Cells (Adv. Energy Mater. 12/2016)
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