Abstract: A method for producing a 3D sponge based on nanofibers includes the processing steps of producing nanofiber based material, cutting the nanofiber based material in small pieces, suspending the small pieces into a wetting non-dissolving liquid, homogenizing the suspension to obtain a slurry with separated short nanofibers, freezing the slurry at a controlled rate and generating a solid templated 3D network of short nanofibers, and thermally, physically or chemically cross-linking the short nanofibers to improve the mechanical stability of the produced sponge.

Abstract: A device for filtering contaminated air includes an air filter, an intake fan driven by an electric motor, a filter housing, to which the air filter can be fastened by means of a threaded connection, and a battery for driving the electric motor, wherein the intake fan has a guide blade and an impeller, and the intake fan is arranged in a chimney-shaped shell on the filter housing.

Abstract: A device for filtering contaminated air includes an air filter, an intake fan driven by an electric motor, a filter housing, to which the air filter can be fastened by means of a threaded connection, and a battery for driving the electric motor, wherein the intake fan has a guide blade and an impeller, and the intake fan is arranged in a chimney-shaped shell on the filter housing.