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Given that power-split transmission (PST) is considered to be a major powertrain technology for hybrid heavy-duty vehicles (HDVs), the development and application of PST in the HDVs make mode shift control an essential aspect of powertrain system design. This paper presents a shift schedule design and torque control strategy for a hybrid HDV with PST during mode shift, intended to reduce the output torque variation and improve the shift quality (SQ). Firstly, detailed dynamic models of the hybrid HDV are developed to analyze the mode shift characteristics. Then, a gear shift schedule calculation method including a dynamic shift schedule and an economic shift schedule is provided. Based on the dynamic models and the designed shift schedule, a mode shift performance simulator is built using MATLAB/Simulink, and simulations are carried out. Through analysis of the dynamic equations, it is seen that the inertia torques of the motor-generator lead to the occurrence of transition torque. To avoid the unwanted transition torque, we use a mode shift control strategy that coordinates the motor-generator torque to compensate for the transition torque. The simulation and experimental results demonstrate that the output torque variation during mode shift is effectively reduced by the proposed control strategy, thereby improving the SQ.

Our previous study has proven that waterborne hydrogen peroxide can affect the arsenic releasing process from arsenopyrite powder, but little is known about the change of morphology and element constitutes on arsenopyrite surface. In this study, a simulated experiment was conducted to examine the effects of hydrogen peroxide (at a concentration range of 5-50 μM) on the abiotic oxidation of arsenopyrite cubes. Scanning electron microscopy (SEM), energy dispersive X-ray spectrometer (EDS), and X-ray photoelectron spectroscopy (XPS) were used to characterize the changes of microstructure morphology and elemental species on arsenopyrite surface. The results showed that micromolar level of H2O2 accelerated the release of arsenic and iron but passivated the sulfur release from arsenopyrite surfaces. As(III) oxidation in solution was enhanced at the early part of the experiment, but the release of As(III) was facilitated at the latter part. As(V) concentrations in solution increased along with the elevated H2O2 dosage level. The SEM images showed different surface microstructure on the surface of CK and all the treatments. EDS results showed that the ratios of S/Fe, Fe/As, and S/As in bulk arsenopyrite revealed evident increasing trend along with the increase of H2O2 dosage level. As the result of surface leaching, the XPS results did not show significant trend, while it suggests that H2O2 accelerated the formation of Fe-As oxidized layer on the arsenopyrite surface.