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Showing 2 results for Feather

S. Mehrban , M. Bahreini , A. Asoodeh , B. Korozhdehi,
Volume 10, Issue 4 (12-2019)
Abstract

Aims: Significant amounts of waste, including feathers, bones, blood, etc. are yearly produced by the poultry industry. Feathers are composed of 90% keratin protein, and the rest is composed of lipids and water. Keratinases are one of the most diverse and usable enzymes, which can be produced by bacterial and fungal microorganisms. These enzymes show a wide range of application in various fields.
Materials and Methods: In this study, the keratinolytic activity of the isolated strain from a poultry farm in Mashhad was evaluated and then the medium conditions for keratinase production were optimized. The strains were identified based on the morphological and biochemical methods. 16SrRNA gene of the strain was amplified by PCR and then sequenced. The strain proteolytic activity was examined and compared with its keratinolytic activity. Finally, strain growth ability tested in variety substrate.
Findings: Using 16SrRNA gene sequencing, morphological and biochemical identification, the strain shared 99.9% similarity with Bacillus mojavensis. Optimization of various factors, including temperature, pH, incubation time, carbon and nitrogen sources, aeration and inoculum size showed that the isolated strain has the highest keratinolytic activity at 37°C, 48 hour incubation period, pH=9.5, sucrose 1%, 3% substrate, aeration 75% and 6% (v/v) inoculum amount. None of the nitrogen sources had a positive effect.
Conclusion: The FUM-1 keratinolytic activity was increased approximately 3.38 fold by condition optimization of the medium, indicating the importance of environmental conditions. In the study, the strain with high keratinolytic activity was suggesting its potential use in biotechnological.


Volume 18, Issue 2 (4-2018)
Abstract

In this research, pitching and plunging motion of bio inspired and NACA airfoil are simulated numerically and the effects of reduced frequency, pitching and plunging amplitude on aerodynamic coefficients, power-extraction and propulsion efficiency are investigated and compared with each other. The simulation is done at Reynolds number of 1100 which is correspond to insect flight regime, using dynamic mesh capability of OpenFoam and fluid flow is assumed unsteady, viscous and laminar. In order to computation of fluid flow field, control volume method is used and value of variables store at the center of control volume. Reduced frequency, plunging and pitching amplitudes vary between 0.05-0.5, 0.25-1.75, 15-75 respectively and phase difference between pitching and plunging motion is kept constant at 90 degrees. Comparison of result with published data confirms the validation of research. Combination of different motion parameter such as reduced frequency, pitching and plunging amplitudes determine that bio inspired airfoil acting in power-extraction (fluid works on the airfoil), propulsion (airfoil works on the fluid) or feather (no producing power or propulsion) regime, and qualitatively is the same as NACA airfoil. The obtained results shows that with variation of reduced frequency, pitching and plunging amplitudes, whatever close to the feathering regime, bio inspired airfoil shows higher efficiency than NACA airfoil and vice versa.

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