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Aiming at reducing the effect of time delay on the control performance of magnetorheological (MR) damper semi-active suspension, a control strategy with strong robustness to time delay is investigated in this study, including the force controller of MR damper, the robust controller and the predictive compensator. The force controller of MR damper is built based on the hyperbolic tangent function; the robust controller is built based on the simplified model of car body lateral vibration and is designed by μ-synthesis method considering the effect of time delay; then the Smith predictive model and the lateral velocity predictor are designed, which form the predictive compensator of semi-active controller to reduce the effect of time delay. To validate the effectiveness of the proposed control strategy, several conventional semi-active controllers are designed as comparative objects. The simulation results show that the proposed semi-active control strategy can maintain good performance when time delay is in the range of 0–100 ms and has better robustness to time delay compared with the conventional control strategy. [ABSTRACT FROM AUTHOR]

Electrochemical CO 2 reduction reaction (CO 2 RR) to multicarbon (C 2+ ) products faces challenges of unsatisfactory selectivity and stability. Guided by finite element method (FEM) simulation, a nanoreactor with cavity structure can facilitate C-C coupling by enriching *CO intermediates, thus enhancing the selectivity of C 2+ products. We designed a stable carbon-based nanoreactor with cavity structure and Cu active sites. The unique geometric structure endows the carbon-based nanoreactor with a remarkable C 2+ product faradaic efficiency (80.5%) and C 2+ -to-C 1 selectivity (8.1) during the CO 2 electroreduction. Furthermore, it shows that the carbon shell could efficiently stabilize and highly disperse the Cu active sites for above 20 hours of testing. A remarkable C 2+ partial current density of-323 mA cm -2 was also achieved in a flow cell device. In situ Raman spectra and density functional theory (DFT) calculation studies validated that the *CO atop intermediates are concentrated in the nanoreactor, which reduces the free energy of C-C coupling. This work unveiled a simple catalyst design strategy that would be applied to improve C 2+ product selectivity and stability by rationalizing the geometric structures and components of catalysts., Competing Interests: The authors declare no competing interests., (This journal is © The Royal Society of Chemistry.)