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Two new molecules based on 2-(2-alkoxy-1-naphthyl)-2,3-dihydro-1h-perimidine are synthesized. The binding properties are investigated by fluorescence spectroscopy showing that one of the products (2a) can selectively bind Cu2+ with fluorescence enhancement. [ABSTRACT FROM AUTHOR]

Due to the effect of biofouling and different mission sensors that may be onboard, hydrodynamic coefficients of underwater glider (UG) may experience gradual or obvious changes, which increases the energy consumption and reduces the glide range. This paper proposes a controllable wing mechanism (CWM) for UG, which enables it adjust the hydrodynamic coefficients and kinematic performance without changing the net buoyancy. Only by two degrees of freedom (DoF), that CWM can realize the control of wingspan, sweep back angle and chord width. To apply the hydrodynamics controlled with CWM in glide model, the fitting precision of hydrodynamics function is improved based on backpropagation artificial neural network (BPANN). A nonlinear state observer based on finite impulse response (FIR) filter is employed for state estimation and random noise interference filtering to realize measurements and evaluation of velocity and reduce the attitude angle measurement error for UG. Then, the FIR-based fuzzy PID (FFPID) controller is established for a steady-state gliding motion control, which suppresses the unknown interference to stablize the system quickly. Finally, the effectiveness of the FFPID closed-loop controller and observer is verified through the simulation in matlab and the experimental test of the UG with CWMs in a water tank. • The proposed CWM can effectively adjust the hydrodynamic coefficient such as drag, which helps control the gliding parameters of the UG. • The BPANN is used to learn the hydrodynamic parameters under different working conditions, and the fitting accuracy of hydrodynamic coefficients with wing parameters is further improved. This method reduces the workload and time for hydrodynamic calculation. • In order to reduce the influence of external environment disturbance on the control system, FIR filter is used for state estimation and random noise filtering, and the FIR coefficient is optimized by GOA algorithm. FFPID controller is used to eliminate the influence of different wing parameters on the control system, although the addition of FIR will increase the adjustment time of FPID to some extent. [ABSTRACT FROM AUTHOR]