Abstract: Provided are a fan assembly and a vacuum cleaner having same. The fan assembly includes a housing, an impeller assembly, and a driving member. At least part of the impeller assembly is accommodated in the housing. The impeller assembly includes a plurality of impellers connected in series in an airflow flowing direction of the fan assembly. The driving member is configured to drive the plurality of impellers to rotate.

Abstract: Provided are a fan assembly and a vacuum cleaner having same. The fan assembly includes a housing, an impeller assembly, and a driving member. At least part of the impeller assembly is accommodated in the housing. The impeller assembly includes a plurality of impellers connected in series in an airflow flowing direction of the fan assembly. The driving member is configured to drive the plurality of impellers to rotate.

Abstract: Provided are a fan assembly and a vacuum cleaner having same. The fan assembly includes a housing, an impeller assembly, and a driving member. At least part of the impeller assembly is accommodated in the housing. The impeller assembly includes a plurality of impellers connected in series in an airflow flowing direction of the fan assembly. The driving member is configured to drive the plurality of impellers to rotate.

Abstract: A nitrogen-doped porous carbon material and a preparation method and an application thereof; wherein the nitrogen-doped porous carbon material has a specific surface area of 1600-3500 m2·g?1, mesopores with a pore size of 2-50 nm account for 20-40% of all pores, an average pore size is 2-20 nm, and a mass fraction of nitrogen atoms in the porous carbon material is 13.6-19.3 wt %. When being used as a supercapacitor material, the porous carbon material has a larger specific capacitance and a better capacitance retention rate. At a current density of 0.1 A·g?1, the porous carbon material has a specific capacitance of about 847 F·g?1. After 5000 cycles of charging and discharging, the capacitance retention rate is about 99.7%. Moreover, the porous carbon material features an excellent pore structure distribution, thus providing good CO2 adsorption performance.