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Two bis-cyclometalated heteroleptic iridium complexes incorporating 1-phenylisoquinoline (piq) as the main cyclometalating ligand and 3-hydroxy-2-methyl-4-pyrone (ma) or 2-ethyl-3-hydroxy-4H-pyran-4-one (ema) as the auxiliary ligand, namely Ir(piq)2(ma) (Ir-1) and Ir(piq)2(ema) (Ir-2), were developed and applied as deep-red phosphors in organic light-emitting diodes (OLEDs). The two auxiliary ligands had similar influences on the photophysical, electrochemical, and electroluminescent properties of the iridium complexes. Ir(piq)2(ma) (Ir-1) showed better luminescence performance in a simple phosphorescent OLED compared to the traditional red iridium complex Ir(piq)2(acac) and exhibited a current efficiency of 9.39 cd A−1 (EQE of 12.09%). In contrast, Ir(piq)2(ema) exhibited an efficiency of 8.6 cd A−1 (EQE of 10.19%).

The recovery of valuable gold from wastewater is of great interest because of the widespread use of the precious metal in various fields and the pollution generated by gold-containing wastes in water. In this paper, a water-insoluble cross-linked adsorbent material (TE) based on cyanuric chloride (TCT) and ethylenediamine (EDA) was designed and used for the adsorption of Au(III) from wastewater. It was found that TE showed extremely high selectivity (D = 49,213.46) and adsorption capacity (256.19 mg/g) for Au(III) under acidic conditions. The adsorption rate remained above 90% eVen after five adsorption–desorption cycles. The adsorption process followed the pseudo-first-order kinetic model and the Freundlich isotherm model, suggesting that physical adsorption with a multilayer molecular overlay dominates. Meanwhile, the adsorption mechanism was obtained by DFT calculation and XPS analysis, and the adsorption mechanism was mainly the electrostatic interaction and electron transfer between the protonated N atoms in the adsorbent (TE) and AuCl4−, which resulted in the redox reaction. The whole adsorption process was the result of the simultaneous action of physical and chemical adsorption. In conclusion, the adsorbent material TE shows great potential for gold adsorption and recovery.

With the increase of hexavalent Cr(VI) wastewater discharged from industrial production, it seriously pollutes water bodies and poses a risk to human health. Adsorption is used as an effective means to treat Cr(VI), but its effectiveness is affected by pH, and the adsorption performance decreases when acidity is strong. Furthermore, research on the mechanism of Cr(VI) adsorption using DFT calculations needs to be developed. This study focuses on the development of magnetically responsive core–shell nano-ion imprinted materials (Fe3O4@GO@IIP) through magnetic separation and surface imprinting techniques. Characterization techniques including FT-IR, XRD, and EDS confirmed the core–shell nanostructure of Fe3O4@GO@IIP. Batch adsorption experiments and model simulations demonstrated the exceptional adsorption capacity of Fe3O4@GO@IIP for Cr(VI) in strongly acidic solutions (pH = 1), reaching a maximum of 89.18 mg/g. The adsorption mechanism was elucidated through XPS and DFT calculations, revealing that Fe3O4@GO@IIP operates through electrostatic interactions and chemical adsorption, with charge transfer dynamics quantified during the process. This research provides new insights for addressing Cr(VI) treatment in highly acidic environments.

The recovery of Au(III) from solution using adsorbents in the form of granules or powders is challenging due to issues such as instability during the recovery process or mass loss caused by small particle size. This study introduces a PEI-TCT/PVDF composite membrane designed to intercept and capture Au(III) in wastewater. Experimental results demonstrated that the PEI-TCT/PVDF membrane exhibits a broad pH range (1–8) and a high retention efficiency for Au(III) of 97.8%, with a maximum adsorption capacity of 294.5 mg/g. The mechanism of Au(III) adsorption on the PEI-TCT/PVDF membrane was mainly through electrostatic adsorption, which caused AuCl4− to aggregate on the surface of the membrane and gradually reduced to Au0 and Au+. Furthermore, the membrane can be entirely regenerated within 20 min and maintains its performance in subsequent adsorption cycles. This study highlights the potential of PEI-TCT/PVDF membranes for the recovery of precious Au(III).

Aiming at the nonlinear low-speed-jitter (LSJ) vibration suppression for a yaw system of a megawatt wind turbine, a kinematics mechanism of the yaw system is investigated from the perspective of tribology, and a kinematics model of the yaw system based on an equilibrium position is established. On the basis of the dynamic modeling of the yaw system, a nonlinear mathematical model of the LSJ system is deduced. Based on the two lead motors’ driving of the conventional yaw motion, an innovative design with a special installation of two auxiliary motors for yaw transmission is carried out, which is integrated with a matching centralized lubrication system (CLS). Based on open-loop proportional-derivative (PD) control and the iterative learning control methods of the time-varying continuous system, the stability control and jitter amplitude suppression of the yaw system are realized by using a combined driving torque provided by the lead and auxiliary gears. From the stability and convergence of the time-domain response and the convergence of the iterative error, the effectiveness of the iterative learning control method with the PD-based regulation is verified, and its advantages for engineering applications are shown based on the algorithm solver improvement. The feasibility of the physical realization and engineering application of the control methodology is verified by using controller-hardware-in-the-loop (C-HITL) simulation technology.

Designing high-performance materials for the detection or removal of toxic decomposition gases of sulfur hexafluoride is crucial for both environmental monitoring and human health preservation. Based on first-principles calculations, the adsorption performance and gas-sensing properties of unsubstituted phthalocyanine (H2Pc) and H2Pc doped with 4d transition metal atoms (TM = Tc and Ru) towards five characteristic decomposition components (HF, H2S, SO2, SOF2, and SO2F2) were simulated. The findings indicate that both the TcPc and RuPc monolayers are thermodynamically and dynamically stable. The analysis of the adsorption energy indicates that H2S, SO2, SOF2, and SO2F2 underwent chemisorption on the TcPc monolayer. Conversely, the HF molecules were physisorbed through interactions with H atoms. The chemical adsorption of H2S, SO2, and SOF2 occurred on the RuPc monolayer, while the physical adsorption of HF and SO2F2 molecules was observed. Moreover, the microcosmic mechanism of the gas–adsorbent interaction was elucidated by analyzing the charge density differences, electron density distributions, Hirshfeld charges, and density of states. The TcPc and RuPc monolayers exhibited excellent sensitivity towards H2S, SO2, and SOF2, as evidenced by the substantial alterations in the band gaps and work functions of the TcPc and RuPc nanosheets. Our calculations hold significant value for exploring the potential chemical sensing applications of TcPc and RuPc monolayers in gas sensing, with a specific focus on detecting sulfur hexafluoride.

The design of the good-performance materials for toxic formaldehyde (CH2O)-gas-detection is critical for environmental preservation and human health. In this work, density functional theory (DFT) calculations were employed to investigate the adsorption behavior and electronic properties of CH2O on transition metal (TM)-doped phthalocyanine monolayers. Our results prove that PdPc and RuPc monolayers are thermodynamically stable. Analysis of the adsorption energy showed that the CH2O gas molecule was chemisorbed on the RuPc monolayer, while it was physisorbed on the PdPc nanosheet. The microcosmic interaction mechanism within the gas-adsorbent system was revealed by analyzing the density of states, the charge-density difference, the electron-density distribution, and the Hirshfeld charge transfer. Additionally, the RuPc monolayer was highly sensitive to CH2O due to the obvious changes in electrical conductivity, and the recovery time of CH2O molecule was predicted to be 2427 s at room temperature. Therefore, the RuPc monolayer can be regarded as a promising gas-sensing material for CH2O detection.