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This paper aims to improve the anti-corrosion of oil transportation pipelines.

The authors provide a simple, efficient and inexpensive one-pot method for the novel thiadiazole derivatives synthesized using 2-substituted [1, 3, 4] thiadiazole, P₂O₅ and chloroacetic acid as materials by using XH-200A computer microwave solid-liquid phase synthesizer. The results showed that microwave heating can finish the reaction sufficiently in 20 min, and the optimal addition reaction conditions were n([1, 3, 4] thiadiazole):n(chloroacetic acid):P₂O₅ = 1:1.2:1.3. Under such conditions, the yield of the title products was 54 per cent.

The structure of the title compounds were all confirmed by Fourier transform infrared spectroscopy and ¹H nuclear magnetic resonance spectroscopy. Water-based inhibitors corrosion behaviors on the stainless steel (SS) surface in 1 mol/L HCl solution at room temperature were also studied by weight loss methods and polarization curves. The results of the curves showed that an appropriate amount of 2a (40 ppm) can improve the anti-corrosion efficiency, whereas an excessive amount of 2a (e.g. 50 ppm) may not significantly increase the anti-corrosion efficiency.

In view of continuation of our studies, this paper presents microwave-assisted one-pot synthesis of 2-substitued [1, 3, 4] thiadiazole derivatives, and its anti-corrosion performance was tested by weight loss methods and polarization curves.

Bionic flapping-wing aerial vehicles (FWAVs) mimic natural flyers to generate the lift and thrust, such as birds, bats and insects. As an important component of the FWAVs, the flapping wings are crucial for the flight performance. The aim of this paper is to study the effects of different wings on aerodynamic performance.

Inspired by the wings structure of birds, the authors design four cambered wings to analyze the effect of airfoils on the FWAVs aerodynamic performance. The authors design the motor-driven mechanism of flapping wings, and realize the control of flapping frequency. Combined with the wind tunnel equipment, the authors build the FWAVs force test platform to test the static and dynamic aerodynamic performance of different flapping wings under the state variables of flapping frequency, wind speed and inclined angle.

The results show that the aerodynamic performance of flapping wing with a camber of 20 mm is the best. Compared with flat wing, the average lift can be improved by 59.5%.

Different from the traditional flat wing design of FWAVs, different cambered flapping wings are given in this paper. The influence of airfoils on aerodynamic performance of FWAVs is analyzed and the optimal flapping wing is obtained.