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Direct air capture (DAC) is a promising technology for decarbonization through the removal of CO2 from the atmosphere. In many DAC processes, the regeneration energy used to restore the capture capacity of sorbents accounts for a significant fraction of the energy required by the whole process. Here we report an effective and scalable sorbent regeneration method for liquid DAC solvents based on magnetic nanoparticles (MNPs) heating with AC magnetic fields. MNPs can be directly heated to provide uniform and rapid volumetric heating, as we demonstrate by promoting the release of captured CO2 from an aqueous solution of potassium sarcosinate. Our results showed that 90% of the solvent can be regenerated within 7.5 min of heating through proposed technique. The MNPs and solvent are found to be stable during the regeneration process and the MNPs showed long‐term stability in the CO2‐saturated solvent. Cyclic experiments showed that the nanoparticles can be reused for multiple cycles without performance deterioration. The process is operated in a noncontact mode through electromagnetic waves, making it an adoptable approach for existing carbon capture systems. The MNPs heating provides an effective regeneration strategy for liquid solvents used in carbon capture processes, in particular for DAC. [ABSTRACT FROM AUTHOR]

The mechanical behavior and cracking patterns of thermally‐shocked additively manufactured alumina were investigated. The flexural strength of test specimens that had been heated to temperatures ranging from 200°C to 1000°C and then rapidly quenched in water was determined at ambient temperature by four‐point bending. Results indicated that the surface cracking patterns had a multifractal structure and that an increase in the thermal shock temperature led to an increase in the density and uniformity of the crack network. The flexural strength results were analyzed with Weibull statistics, where the Weibull moduli for most of the thermal shock conditions tested were found to be statistically indistinguishable. It was also found that a significant decrease (∼50%) in flexural strength occurred for heating temperatures ≥300°C. The effect of the manufacturing method on cracking patterns is discussed, as well as the implication of the material behavior for practical applications of these materials. [ABSTRACT FROM AUTHOR]