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Typical forward osmosis (FO) membranes utilize non-woven fabrics or polymers as support layers, which cause severe internal concentration polarization (ICP) effects due to their unalterable thickness, thereby limiting the water flux. Herein, an ultrathin composite film based on carbon nanotubes (CNTs) and polyvinyl alcohol (PVA), with a thickness controlled down to 10.3 μm, is proposed as a support layer for the fabrication of FO membranes for application in polluted water treatments and desalination. Our observations reveal that incorporating PVA into the CNT film boosts mechanical strength and hydrophilicity, thereby efficiently alleviating the ICP effect during the FO process. Moreover, employing a uniform polydopamine (PDA) film as the interlayer reduces the pore size and roughness of the substrates, thus facilitating the formation of an ultrathin, continuous, and intact polyamide (PA) selective layer. With deionized water as the feed solution and a 1 M sodium chloride solution as the draw solution, the optimized membrane achieves an extremely high water flux of up to 90.86 L m−2 h−1 and a specific salt flux of 0.22 g L−1. This work demonstrates an effective strategy to develop FO membranes with reduced membrane thickness while still exhibiting exceptional water flux and good mechanical properties, showcasing its potential in practical FO membrane applications. [ABSTRACT FROM AUTHOR]

The effect of fire source location (FSL) on compartment fire phenomena with a single natural ceiling vent was experimentally investigated under various vent area (VA) and heat release rate (HRR) conditions. Two FSL cases, where the fire source was located at the centre (FSLC) and on the side (FSLS) of the floor, were tested. In the bidirectional vent flow patterns of FSLC and FSLS, the detailed locations where the smoke outflow and the fresh air inflow occurred were different. Empirical correlations were proposed for predicting the smoke outflow areas. FSLC exhibited a higher central velocity of the outflow, larger estimated mass flow rate of the outflow, and lower temperatures inside the compartment than FSLS. The estimated mass flow rate of the outflow depended more on VA than on HRR. A previous correlation was more suitable for FSLS than FSLC in predicting the mass flow rate of the outflow. [ABSTRACT FROM AUTHOR]

Neo magnets are neodymium magnet beads that have been marketed as a desktop toy. We proposed using neo magnets as an alternative building block to traditional ball-and-stick models to construct carbon allotropes, such as fullerene and various nanocone structures. Due to the lack of predetermined physical connections, the versatility of carbon bonding can be allowed for when using magnetic beads, as well as providing a more comprehensive appreciation for the angles required for stable bonding within a structure. The students are asked to make neo magnet models of various nanocone structures as well as using software to create the structures, and then compare cone angles obtained with both methods. This activity was trialed on several discussion groups with positive results and feedback of a deeper understanding for carbon nanostructures.