Finite-Time Thermodynamic Model for Evaluating Heat Engines in Ocean Thermal Energy Conversion.

Ocean thermal energy conversion (OTEC) converts the thermal energy stored in the ocean temperature difference between warm surface seawater and cold deep seawater into electricity. The necessary temperature difference to drive OTEC heat engines is only 15-25 K, which will theoretically be of low thermal efficiency. Research has been conducted to propose unique systems that can increase the thermal efficiency.

Synthesis of zeolites from paper sludge ash and their ability to simultaneously remove NH4+ and PO43-.

The objective of this study was to investigate the synthesis of zeolites from paper sludge ash, and to evaluate their applications for water purification to simultaneously remove NH4+ and PO43- in aqueous solution. Paper sludge ash had a low abundance of Si and a significant Ca content, due to the presence of calcite that was used as paper filler. Na2SiO3 was added to the NaOH solution to increase Si content in order to synthesize zeolites with high cation exchange capacity.

Reaction of arenes with iodine in the presence of potassium peroxodisulfate in trifluoroacetic acid. Direct and simple synthesis of diaryliodonium triflates.

Diaryliodonium triflates have been directly prepared by reaction of arenes with elemental iodine in good yields by using K2S2O8 and TFA, followed by treatment with NaOTf. This procedure avoids the use of high temperature and severe reaction conditions.