Beam-column connections are often assumed rigid in traditional frame analysis, yet they undergo significant shear deformations and greatly contribute to story drifts during earthquake loading. Although local joint models are available in the literature for the investigation of single, isolated joints, there is a lack of holistic frame analysis procedures simulating the joint behavior in addition to important global failure modes such as beam shear, column shear, column axial, and soft story failures. The objective of this study is to capture the impact of local joint deformations on the global frame response in a holistic analysis by implementing a joint model into a previously-developed global frame analysis procedure. The implemented joint element simulates joint shear deformations and bar-slip effects. Concrete confinement effects are also considered so that both older and new joints can be modeled. The developed procedure provides better overall load-deflection response predictions including the local joint response.

All-inorganic perovskite quantum dots (PeQDs) have sparked extensive research focus on white-light-emitting diodes (WLEDs), but stability and photoluminescence efficiency issues are still remain obstacles impeding their practical application. Here, we reported a facile one-step method to synthesize CsPbBr 3 PeQDs at room temperature using branched didodecyldimethylammonium fluoride (DDAF) and short-chain-length octanoic acid as capping ligands. The obtained CsPbBr 3 PeQDs have a nearunity photoluminescence quantum yield of 97% due to the effective passivation of DDAF. More importantly, they exhibit much improved stability against air, heat, and polar solvents, maintaining >70% of initial PL intensity. Making use of these excellent optoelectronic properties, WLEDs based on CsPbBr 3 PeQDs, CsPbBr 1.2 I 1.8 PeQDs, and blue LEDs were fabricated, which show a color gamut of 122.7% of the National Television System Committee standard, a luminous efficacy of 17.1 lm/W, with a color temperature of 5890 K, and CIE coordinates of (0.32, 0.35). These results indicate that the CsPbBr 3 PeQDs have great practical potential in wide-color-gamut displays.

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All-inorganic CsPbI3 perovskite quantum dots (PeQDs) have sparked widespread research due to their excellent optoelectronic properties and facile synthesis. However, attaining highly stable CsPbI3 perovskite quantum dots (PeQDs) against heat and polar solvents still remains a challenge and hinders any further practical application. Here, by exploiting (3-aminopropyl) triethoxysilane (APTES) as the sole silica (SiO2) precursor, we report a one-step in situ synthesis of single SiO2-coated CsPbI3 (SiO2-CsPbI3) PeQDs, namely that one SiO2 particle only contains one CsPbI3 PeQD particle. The obtained SiO2-CsPbI3 PeQDs are cubic in shape, have a more uniform size distribution, and possess narrow emission, with near unit photoluminescence quantum yields of up to 97.5%. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy confirm the formation of SiO2 through the hydrolysis of APTES on the CsPbI3 PeQDs surface. Furthermore, they have a significantly improved stability against storage, heat, and ethanol. By combining purple-emission GaN light-emitting diodes, the SiO2-CsPbI3 PeQDs were successfully employed as down-conversion emitters and exhibited considerable enhanced luminous performance and excellent stability, demonstrating their promising future in the practical application of solid-state lighting fields.