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The core problem of auto-cascading refrigeration is the separation of non-azeotropic refrigerants. The separation effect of mixed refrigerant directly determines the refrigeration effect of auto-cascading refrigeration system and the value of COP. The microscopic molecular dynamics simulation method is applied to the refrigeration system, and the properties of the pure substance and the mixed substance are simulated from the microscopic aspects to study the law of molecular condensation cooling, and the separation rate is simulated to obtain a more optimized scheme.

In this study, the influence of the frictional heat effect on the degree of wear is explored from the perspectives of initial contact positive pressure and frictional relative slip velocity. Experiments based on a multifunctional friction and wear machine show that the friction temperature increases with an increase in friction relative velocity and initial normal contact load, which exacerbates the frictional thermal expansion and normal load fluctuation, and with the generation of frictional heat, the normal force fluctuates periodically; the wear mass and temperature in the contact area iterate cyclically, which results in the wear mass increasing. 316L stainless steel, 5A06 aluminium alloy and pure titanium are used in the Archard wear model due to their applications in severe wear environments. Since 316L stainless steel, 5A06 aluminium alloy and pure titanium are mostly used in wear-intensive environments, the Archard wear model is optimised based on the frictional heat effect of these three materials, and the accuracy of the improved model in 316L stainless steel, 5A06 aluminium alloy and pure titanium is improved by 52.6%, 7.4% and 23.9%, respectively, when compared with the conventional model. This study lays a theoretical foundation for the wear prediction models of 316L stainless steel, 5A06 aluminium alloy and pure titanium. [ABSTRACT FROM AUTHOR]

Microbial fuel cell (MFC) technology can potentially recover bioelectricity from wastewater. However, its practical applications have been limited because of its low power density and since the energy generated from an MFC cannot be stored. In this study, manganese dioxide (MnO2) coupled with carbon nanotubes (CNT) was chosen to in situ modify carbon felt (CF) as a capacitive bioanode (CF/CNT/MnO2) to improve the power generation and energy storage of MFCs. The maximum power density of the MFC with the MnO2-CNT-modified bioanode reached 3471.6 mW m3, which was 1.96 times higher than that of the CF/CNT anode (1772.6 mW m−3). During the experiment of charging for 30 min and discharging for 30 min, the MFC with a capacitive bioanode had a total charge of 8777.1 C m−2, 2.74 times higher than that of the CF/CNT anode. The excellent electricity-producing and energy storage performance of the MFC equipped with the CF/CNT/MnO2 anode is attributed to the composite materials, which can be due to their better biocompatibility, large capacitance, and high specific surface area. This study provides a new way to improve the performance of electricity generation and energy storage of MFCs. [ABSTRACT FROM AUTHOR]