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Lattice deformation via substrate‐driven mechanical straining of 2D materials can profoundly modulate their bandgap by altering the electronic band structure. However, such bandgap modulation is typically short‐lived and weak due to substrate slippage, which restores lattice symmetry and limits strain transfer. Here, it is shown that a non‐volatile thermomechanical strain induced during hot‐press synthesis results in giant modulation of the inherent bandgap in quasi‐2D tellurium nanoflakes (TeNFs). By leveraging the thermal expansion coefficient (TEC) mismatch and maintaining a pressure‐enforced non‐slip condition between TeNFs and the substrate, a non‐volatile and anisotropic compressive strain is attained with ε = −4.01% along zigzag lattice orientation and average biaxial strain of −3.46%. This results in a massive permanent bandgap modulation of 2.3 eV at a rate S (ΔEg) of up to 815 meV/% (TeNF/ITO), exceeding the highest reported values by 200%. Furthermore, TeNFs display long‐term strain retention and exhibit robust band‐to‐band blue photoemission featuring an intrinsic quantum efficiency of 80%. The results show that non‐volatile thermomechanical straining is an efficient substrate‐based bandgap modulation technique scalable to other 2D semiconductors and van der Waals materials for on‐demand nano‐optoelectronic properties. 

The Arctic Ocean has experienced significant sea ice loss over recent decades, shifting towards a thinner and more mobile seasonal ice regime. However, the impacts of these transformations on the upper ocean dynamics of the biologically productive Pacific Arctic continental shelves remain underexplored. Here, we quantified the summer upper mixed layer depth and analyzed its interannual to decadal evolution with sea ice and atmospheric forcing, using hydrographic observations and model reanalysis from 1996 to 2021. Before 2006, a shoaling summer mixed layer was associated with sea ice loss and surface warming. After 2007, however, the upper mixed layer reversed to a generally deepening trend due to markedly lengthened open water duration, enhanced wind-induced mixing, and reduced ice meltwater input. Our findings reveal a shift in the primary drivers of upper ocean dynamics, with surface buoyancy flux dominant initially, followed by a shift to wind forcing despite continued sea ice decline. These changes in upper ocean structure and forcing mechanisms may have substantial implications for the marine ecosystem, potentially contributing to unusual fall phytoplankton blooms and intensified ocean acidification observed in the past decade 

Abstract Agricultural activities are the major anthropogenic source of nitrous oxide (N2O), an important greenhouse gas and ozone-depleting substance. However, the role of forage conservation as a potential source of N2O has rarely been studied. We investigated N2O production from the simulated silage of the three major crops—maize, alfalfa, and sorghum—used for silage in the United States, which comprises over 90% of the total silage production. Our findings revealed that a substantial N2O could be generated, potentially placing forage conservation as the third largest N2O source in the agricultural sector. Notably, the application of chlorate as an additive significantly reduced N2O production, but neither acetylene nor intermittent exposure to oxygen showed any impact. Overall, the results highlight that denitrifiers, rather than nitrifiers, are responsible for N2O production from silage, which was confirmed by molecular analyses. Our study reveals a previously unexplored source of N2O and provides a crucial mechanistic understanding for effective mitigation strategies.