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Solution combustion synthesis (SCS) is considered as an efficient and energy-saving method for preparing LiFePO4/C composite material with the nanostructure (Nano-LiFePO4/C). In this study, Nano-LiFePO4/C cathode material was prepared using SCS using a cost-effective combination of urea and sorbitol as mixed fuels. The effect of mixed fuels on combustion behavior and microstructure as well as on electrochemical performance was studied using XRD, BET, SEM, TEM, and electrochemical characterization methods. Multiple characterization results indicated that the maximum temperature (Tm) and particle size were influenced by the usage of urea and sorbitol. The sample derived under optimum conditions exhibits a mesoporous nanostructure with a large surface specific area and attractive electrochemical performance with a discharge capacity of 153.5 mAh/g at 0.1 C, which shows strong potential for commercial applications in the future. [ABSTRACT FROM AUTHOR]

In the natural gas liquefaction system, droplets formed by condensation of water dew point will cause dew point corrosion of relevant equipment, while the droplets formed by condensation of hydrocarbon dew point will not cause dew point corrosion of equipment, but can inhibit the occurrence of dew point corrosion. In order to find the critical point of water dew point and hydrocarbon dew point of natural gas, a quantitative analysis model of natural gas dew point was established by Aspen Plus software. The dew point of light component natural gas and natural gas containing trace heavy component in natural gas liquefaction system was quantitatively analyzed. The influence of natural gas pressure and mole fraction of CO2 in natural gas on dew point was analyzed. The results show that the dew point type of light component natural gas is water dew point, which will cause dew point corrosion to the related equipment of natural gas liquefaction system. Trace C6 heavy components in natural gas will not affect the dew point temperature and dew point solution composition, while trace C7, C8 and C9 heavy components will change the dew point temperature and dew point solution composition. Dew point corrosion of related equipment in natural gas liquefaction system can be prevented by adding trace C9 and C10+ heavy components in natural gas. [ABSTRACT FROM AUTHOR]

Tesla turbines, featuring bladeless turbomachinery and energy transformation using the viscosity of the working medium, have wide application prospects in renewable energy utilization as micropower equipment and portable power units and show better aerodynamic performance with a smaller turbine size. In this paper, a miniaturization method of Tesla turbines, including the stator and rotor, was proposed based on its sensitivity analysis results and flow similitude law. A typical Tesla turbine with a disc outer diameter of 100 mm was miniaturized to 50, 20, and 10 mm, respectively. In addition, the miniaturized Tesla turbines, including both the simplified single‐channel turbine model and the multichannel turbine model used in practical applications, were simulated numerically. The results show that the miniaturization method that maintains the two high‐impact dimensionless parameters at their optimal values is simple, reasonable, and effective. The isentropic efficiency of the single‐channel Tesla turbine decreases slightly with its scaling down. However, for the multichannel Tesla turbine in practical applications, the isentropic efficiency increases significantly with a decrease in turbine size, due to a decrease in the impact of the outermost disc channel on the flow fields of the inner disc channels (called the casing wall effect). This is embodied by the phenomenon that part of the working medium in the inner disc channels flows into the outermost disc channel through the nozzle‐rotor chamber, and the proportion of this part of the working medium decreases significantly with a decrease in turbine size. In conclusion, the Tesla turbine with a smaller turbine size exhibits better aerodynamic performance and has great potential in the field of microturbomachinery. [ABSTRACT FROM AUTHOR]

A green H2 O-promoted solvent-free hydroamination of electron-deficient terminal alkynes with amines has been developed. All secondary amines, including aliphatic and aromatic amines, gave the corresponding (E)-enamines in good to excellent yields, whereas primary aromatic amines afforded Z -configured products in moderate yields. Propiolates, propyn-1-ones, propynamides, and 1-(ethynylsulfonyl)-4-methylbenzene were explored in this Michael addition. [ABSTRACT FROM AUTHOR]