Ultrafiltration of a protein solution at constant volume is achieved by the addition of water or buffer to the feed in an operation called diafiltration. Consider a protein diafiltration system where the flow channels are tubes \(0.2 \mathrm{~cm}\) in diameter and \(1.0 \mathrm{~m}\) long. The protein, which has a molecular weight of \(490 \mathrm{kDa}\), has a diffusion coefficient, \(\mathrm{D}_{s}=1.2 \times 10^{-7} \mathrm{~cm}^{2} / \mathrm{s}\). The solution has a viscosity of \(1.2 \mathrm{cP}\) and a density of \(1100 \mathrm{~kg} / \mathrm{m}^{3}\). The system operates at a bulk stream velocity of \(6.0 \mathrm{~m} / \mathrm{s}\). Under these operating conditions, it has been observed that the concentration polarization modulus, \(c_{s} / c_{R}=3.45\). Assuming complete solute rejection by the membrane, estimate the transmembrane flux, in units of \(\mathrm{L} / \mathrm{m}^{2}-\mathrm{h}\).