The diffusivity of human insulin is 77 µm2 /s in water at 37◦ C. Assuming the protein to be spherical, what is its effective radius? How does this compare to its crystal structure dimensions (77.22 x 77.22 x 77.22 Å)? Hint: The mean frictional drag coefficient for a sphere of radius R = 6πµR

Abrayton cycle operates with a regenerator on the air-standard with properties evaluated at 400 k. the tem- perature of the air entering the compressor is 350k while the temperature of the air exiting the compressor is 600 k. the temperature of the air entering the turbine is 1600 k. the overall cycle produced 600 kj/kg of net work out. assuming a regenerator effectiveness of 0.8, what is the temperature of the air before heat addition (combustion)? draw this process on a t - s diagram