The electrochemistry of Pb(II)/Pb on a stainless steel electrode during the preparation of lead wires from PbO in choline chloride (ChCl)-urea deep eutectic solvent (DES) was investigated by means of cyclic voltammetry, cathodic polarization and chronoamperometry. The experimental results indicated that the reduction of Pb(II) to Pb is a quasi-reversible process controlled by diffusion at temperature varying from 323 to 343 K, and the corresponding apparent activation energy E a is 52.37 kJ mol -1 . The analysis of chro noamperometry measurements suggested that the initial stage of nucleation of lead on stainless steel electrode is a three dimensional instantaneous nucleation under diffusion control. The effects of reaction time and temperature on the morphology of lead deposits are also examined. The lead wires obtained at 343 K for 120 min have a mean particle size of 30 μm in length and 2.5 μm in diameter. Based on experimental evi dence, the deposition mechanism of sub micrometer lead wires on stainless steel substrate is proposed by dif fusion controlled growth mechanism.

In this paper, the complete group classification is performed on the generalized short pulse equation, which includes a lot of important nonlinear wave equations as its special cases. In the sense of geometric symmetry, all of the vector fields of the equation are obtained in terms of the arbitrary functions. Then, the symmetry reductions and exact solutions to the equations are investigated. Especially, we develop the analytic power series method for constructing the exact power series solutions to the short pulse types of equations.

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The catalytic degradation of lignin was exploited by magnetic core‐shell Fe3O4@SiO2@CuZnAl‐O catalysts in supercritical methanol (sc‐MeOH) over temperature from 260 °C to 360 °C and the reaction time ranging from 0.5 h to 5 h. The magnetic core‐shell‐structured Fe3O4@SiO2@CuZnAl‐O catalysts with different mole ratio of Cu to Zn were prepared by parallel flow co‐precipitating method. Catalyst Fe3O4@SiO2@Cu1.2Zn4.8Al2‐O with the maximum specific surface area (142.8 m2 g−1) exhibited the highest lignin conversion of 66% and high selectivity for phenols, ketones and benzenes. The recyclable Fe3O4@SiO2@CuZnAl‐O catalyst allows high catalytic activity and selectivity for phenols, ketones and benzenes in the catalytic conversion of lignin in supercritical methanol. It is believed that this study can provide a promising strategy to prepare core–shell structured base metal nanocatalysts with metal‐oxide shells.