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Abstract This study presents an eco-friendly mechanochemical synthesis of cesium lead bromide (CsPbBr₃), eliminating the need of organic solvents and high temperatures. The synthesized CsPbBr₃powder is used to fabricate poly(methyl methacrylate) (PMMA)-CsPbBr₃films and CsPbBr₃nanocrystals (NCs). The photoluminescence (PL) peaks of the emission light are centered at 541 nm, 538 nm, and 514 nm for the CsPbBr₃powder, PMMA-CsPbBr₃films, and CsPbBr₃NCs, respectively, correlating with crystal sizes of 0.96, 0.56, and 0.12μm, respectively. The PL lifetime analysis reveals decay times ( ${\tau }_1,{\tau }_2$) of (4.18, 20.08), (5.7, 46.99), and (5.81, 23.14) in the units (ns, ns) for the CsPbBr₃powder, PMMA-CsPbBr₃films, and CsPbBr₃NCs, respectively. The PL quantum yield of the CsPbBr₃NCs in toluene is 61.3%. Thermal activation energies for thermal quenching are 217.48 meV (films) and 178.15 meV (powder), indicating improved thermal stability with the PMMA encapsulation. The analysis of the PL intensity decay from water diffusion in the PMMA-CsPbBr₃films yields 1.70 × 10⁻¹²m²s⁻¹for the diffusion coefficient of water, comparable to that for water diffusion in pure PMMA. This work demonstrates a scalable, sustainable strategy for CsPbBr₃synthesis and stability enhancement for optoelectronic applications. 

Abstract The intricate currents of the Northwest Pacific Ocean, with strong manifestations along the westside rim, connect tropical and subtropical gyres and significantly influence East Asian and global climates. The El Niño/Southern Oscillation (ENSO) originates in the tropical Pacific Ocean and disrupts this ocean circulation system. However, the spatiotemporal dependence of the impact of ENSO events has yet to be elucidated because of the complexities of both ENSO events and circulation systems, as well as the increased availability of observational data. We thus combined altimeter and drifter observations to demonstrate the distinct tropical and subtropical influences of the circulation system on ENSO diversity. During El Niño years, the North Equatorial Current, North Equatorial Countercurrent, Mindanao Current, Indonesian Throughflow, and the subtropical Kuroshio Current and its Extension region exhibit strengthening, while the tropical Kuroshio Current weakens. The tropical impact is characterized by sea level changes in the warm pool, whereas the subtropical influence is driven by variations in the wind stress curl. The tropical and subtropical influences are amplified during the Centra Pacific El Niño years compared to the Eastern Pacific El Niño years. As the globe warms, these impacts are anticipated to intensify. Thus, strengthening observation systems and refining climate models are essential for understanding and projecting the enhancing influences of ENSO on the Northwest Pacific Oceanic circulation.