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"Desired higher ship speeds can be achieved using many performance enhancement techniques. One of the techniques is drag reduction of ships’ hulls by imbuing their surfaces with hydrophobic properties This paper presents an alternative method of fabricating micro-riblets using laminate transfer molding to modify painting morphology for micro-riblets’ replication on ships’ hulls. A performance test of these micro-riblets is also performed. The results show that micro-riblets can be replicated from the pattern to the ships’ hulls. The geometries of micro-riblets are verified, which shows good agreement with the pattern. The performance of the fabricated micro-riblets was verified to decrease drag on the ship. As a result, ships’ speeds increased under similar propulsion power. The significant effect of micro-riblets is obtained with these higher speeds."

"The aim of this study is to evaluate the effects of absorbent flow rate on CO2 absorption through a super hydrophobic hollow fiber contactor. The absorbent used in this study was a physical absorbent, namely a polyethyleneglycol-300 (PEG-300) solution. Meanwhile, the feed gases used in the experiments were pure CO2 and a mixture of 30% CO2 and 70% CH4. Gas absorption using a physical absorbent provides various benefits; for example, it can produce sufficiently high selectivity towards CO2 and it is less corrosive than chemical solvents. Three super hydrophobic hollow fiber contactors, each 6 cm in diameter and 25 cm in lengthconsist of 1000, 3000 and 5000 fibers, respectively, were used in this study. The type ofsuper hydrophobic fiber membrane used was polypropylene-based, with an outer and inner diameter of about 525 and 235 µm, respectively. During the experiments, the absorbent was flowed through the lumen fibers, whilst the feed gas flowed through the shell side of the membrane contactors. The experimental results showed that the mass transfer coefficient, the flux, and the absorption efficiency increased, but the CO2 loading decreased, with increasing absorbent flow rate in the membrane contactor. Meanwhile, it was found that an increase in the number of fibers in the membrane contactor, in general, will increase the absorption efficiency and the CO2 loading, but will decrease the overall mass transfer coefficient and the flux."