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Microfluidic Electro-Viscoelastic Separation of Submicron Particles and Extracellular Vesicles
No full textIsolating submicron and nanoparticles in microfluidics is challenging due to weak separation forces and dominance of diffusion at the nanoscale. While the unfavorable scaling of the separation forces can be addressed by nanofluidic systems, the operation of such systems faces several limitations such as low throughput, high pressure requirements, and clogging. To overcome these issues, we present electro-viscoelastic particle separation─a method combining electrophoretic slip-induced lift with viscoelastic microfluidics to enhance lateral forces on nanoparticles. Using a standard microchannel (60 μm height, 20 μm width, and 3 cm length), we demonstrated fractionation of a mixture of submicron polystyrene particles with different sizes in a viscoelastic medium under an applied electric field. This system improved the purity of 50, 200, and 500 nm particles by 39%, 29%, and 50%, respectively. We further applied this technique to purify cancer cell–secreted extracellular vesicles (EVs) from background nanoscale contaminants such as soluble proteins, achieving a 22% increase in EV purity. Notably, our platform operates at blockage ratios as low as 0.002, which is a considerable improvement over its inertial and viscoelastic counterparts. These experimental findings highlight the potential of integrating electric fields with viscoelastic migration for effective nanoparticle separation. A comparison of our results with state-of-the-art theoretical models of electro-viscoelastic migration (EVM) suggests that the current understanding requires further advancement. Nevertheless, the enhanced electro-viscoelastic lift predicted by these models underscores the prospect of this technique for separation of bionanoparticles.</p
Evaluation of non-destructive examination requirements and challenges for small modular reactors
No full textThis study evaluates the applicability of Non-Destructive Examination (NDE) methods to the BWRX-300, i-SMR, and Rolls-Royce SMR Small Modular Reactor (SMR) designs, as well as to Generation IV concepts: GTHTR300, IMSR 400, and 4S. The assessment considers plant design, structural materials, and manufacturing technologies to identify corresponding NDE requirements for both manufacturing and in-service inspections. The findings suggest that, for near-term deployable SMRs, existing inspection methods used in the conventional large-scale nuclear power plants remain applicable. However, the introduction of new materials, novel reactor designs, advanced manufacturing techniques, and the modular design, may require adaptations or development of new NDE approaches
Microfluidic Electro-Viscoelastic Separation of Submicron Particles and Extracellular Vesicles
No full textIsolating submicron and nanoparticles in microfluidics is challenging due to weak separation forces and dominance of diffusion at the nanoscale. While the unfavorable scaling of the separation forces can be addressed by nanofluidic systems, the operation of such systems faces several limitations such as low throughput, high pressure requirements, and clogging. To overcome these issues, we present electro-viscoelastic particle separation─a method combining electrophoretic slip-induced lift with viscoelastic microfluidics to enhance lateral forces on nanoparticles. Using a standard microchannel (60 μm height, 20 μm width, and 3 cm length), we demonstrated fractionation of a mixture of submicron polystyrene particles with different sizes in a viscoelastic medium under an applied electric field. This system improved the purity of 50, 200, and 500 nm particles by 39%, 29%, and 50%, respectively. We further applied this technique to purify cancer cell–secreted extracellular vesicles (EVs) from background nanoscale contaminants such as soluble proteins, achieving a 22% increase in EV purity. Notably, our platform operates at blockage ratios as low as 0.002, which is a considerable improvement over its inertial and viscoelastic counterparts. These experimental findings highlight the potential of integrating electric fields with viscoelastic migration for effective nanoparticle separation. A comparison of our results with state-of-the-art theoretical models of electro-viscoelastic migration (EVM) suggests that the current understanding requires further advancement. Nevertheless, the enhanced electro-viscoelastic lift predicted by these models underscores the prospect of this technique for separation of bionanoparticles.</p
Progress in deep cleaning and upgrading of biomass- and waste-derived syngas for production of renewable fuels, chemicals and power
No full textThe cleaning of syngas for the production of renewable fuels, chemicals and power is reviewed here. Recent progress in syngas cleaning pathways and key utilization routes, along with techno-economics are discussed, with the goal of investigating the requirements of crude syngas towards clean syngas and finally towards fuels and chemicals as a sustainable and eco-friendly technology. The impacts of feedstock composition, type and characteristic properties on syngas quality coupled with the role of different impurities are examined. Furthermore, adaptation of process parameters and its impact on the syngas quality is discussed. Cleaning of crude syngas is considered a critical issue to generate renewable fuels and chemicals, and therefore, diverse pathways (conventional such as hot and cold cleaning methods, catalytic cleaning and thermal cracking and, advanced techniques such as membranes, pressure swing adsorption, and cryogenic separation) are presented to allow effective cleaning which in turn can enable syngas deployment in various applications. Bio-methane has emerged as a beneficial alternative for conventional transportation fuel with all the advantages of natural gas including a dense distribution, trade and supply network. Gasification is a proven technology while gas cleaning is still one limiting factor since “classical” pathways are labor and cost intensive, especially when it comes to residues and waste materials as feedstock. Gasification of organic feedstock materials (clean biomass, residues and waste) followed by chemical synthesis is a key-technology to substitute chemicals and fuels from fossil sources. These syngas-derived fuels and chemicals have the potential to provide sustainable energy and curb climate change to a major extent and therefore, can be a step forward towards the United Nation's Sustainable Development Goals 7 and 13.</p
Microfluidic Electro-Viscoelastic Separation of Submicron Particles and Extracellular Vesicles
No full textIsolating submicron and nanoparticles in microfluidics is challenging due to weak separation forces and dominance of diffusion at the nanoscale. While the unfavorable scaling of the separation forces can be addressed by nanofluidic systems, the operation of such systems faces several limitations such as low throughput, high pressure requirements, and clogging. To overcome these issues, we present electro-viscoelastic particle separation─a method combining electrophoretic slip-induced lift with viscoelastic microfluidics to enhance lateral forces on nanoparticles. Using a standard microchannel (60 μm height, 20 μm width, and 3 cm length), we demonstrated fractionation of a mixture of submicron polystyrene particles with different sizes in a viscoelastic medium under an applied electric field. This system improved the purity of 50, 200, and 500 nm particles by 39%, 29%, and 50%, respectively. We further applied this technique to purify cancer cell–secreted extracellular vesicles (EVs) from background nanoscale contaminants such as soluble proteins, achieving a 22% increase in EV purity. Notably, our platform operates at blockage ratios as low as 0.002, which is a considerable improvement over its inertial and viscoelastic counterparts. These experimental findings highlight the potential of integrating electric fields with viscoelastic migration for effective nanoparticle separation. A comparison of our results with state-of-the-art theoretical models of electro-viscoelastic migration (EVM) suggests that the current understanding requires further advancement. Nevertheless, the enhanced electro-viscoelastic lift predicted by these models underscores the prospect of this technique for separation of bionanoparticles.</p
