Characterisation of deformation and breakage of agglomerates

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Engineering of oriented carbon nanotubes in composite materials

The orientation and arrangement engineering of carbon nanotubes (CNTs) in composite structures is considered a challenging issue. In this regard, two groups of in situ and ex situ techniques have been developed. In the first, the arrangement is achieved during CNT growth, while in the latter, the CNTs are initially grown in random orientation and the arrangement is then achieved during the device integration process. As the ex situ techniques are free from growth restrictions and more flexible in terms of controlling the alignment and sorting of the CNTs, they are considered by some as the preferred technique for engineering of oriented CNTs. This review focuses on recent progress in the improvement of the orientation and alignment of CNTs in composite materials. Moreover, the advantages and disadvantages of the processes are discussed as well as their future outlook

Controllability of the hydrophilic or hydrophobic behavior of the modified polysulfone electrospun nanofiber mats

In this study controllability of morphology and wettability behavior of the polysulfone electrospun nanofiber mats (ENMs) by adding the surfactants was investigated. The effect of cationic, anionic, and non-ionic surfactants on diameter size, hydrophilicity or hydrophobicity, surface roughness, and chemical composition of the ENMs was studied using FESEM, contact angle measurement, AFM, and FTIR, respectively. Comparing the surfactant-assisted to surfactant-free nanofibers, the contact angle was decreased (from 115° to 66°) for the SDS. In contrast, it was increased (from 115° to 129°) for the CTAB. A similar trend was observed for the ENMs surface roughness. However, both surfactants caused to decline in the nanofibers' diameter. These observations indicated that by changing the surfactant type, the nanofiber mats surface roughness could be improved whereby the wettability of the fibers would be controlled. These phenomena are thought to be due to change in the solvent evaporation rate during the electrospinning process

Use of high salinity water in a power plant by connecting a direct contact membrane distillation (DCMD) to a steam-injected gas turbine (STIG)

Unlike steam turbines, electricity production in gas turbines is inherently independent of freshwater consumption. However, the thermal efficiency of gas turbines decreases as the temperature of input air increases. As a result, many methods of cooling the inlet air require the use of fresh water. Moreover, when it comes to humid gas turbine technology, the practice of injecting steam or humid air into the turbine to improve its thermal efficiency and output power consumes a substantial amount of freshwater. Therefore, reducing the use of fresh water to enhance the output power and thermal efficiency of gas turbines can be a necessary option, especially in hot and dry regions. Alternatively, considering the significant amounts of waste heat in gas turbines, one solution to reduce fresh water consumption is to connect them to thermal desalination units. However, conventional thermal desalination is only practical for seawater desalination in coastal areas. Therefore, this study explores the possibility of linking a direct contact membrane distillation (DCMD) unit to a Steam-injected gas turbine (STIG), which can use high salinity water sources like reverse osmosis (RO) brine in inland regions. The freshwater generated by the DCMD is used to chill the input air to the compressor and produce steam injected within the turbine. Simulation results show that this connection can raise the net output power by [9 to 17.2] MW and thermal efficiency by [3.3 to 15.6] % for compressor pressure ratios between [5 to 30], when compared to a simple gas turbine

Characterisation of the dispersion behaviour of powders in liquids

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