Abstract: The present invention relates to a method for improving the biocompatibility of a surface, in particular a solid body surface, as well as a device, for example an implant, sensor or cell culture vessel, which is brought in contact with biological systems with a biocompatible surface. To improve the biocompatibility of surfaces, in particular in relation to cell cultures and tissues, in a simple way and for a plurality of different surfaces, the surface is meant to be brought in contact with reactive radicals according to the invention. The device according to the invention has a biocompatible surface that has been treated pursuant to the method according to the invention.

Abstract: A method of etching and a method of regenerating a spent etching solution comprising adding metal particles to a spent etching solution to precipitate the residue metal or metals in the spent etching solution in the form of metal powders, removing the metal powders from the spent etching solution and recovering the metals in the metal powders for future use. The remaining portion of the spent etching solution can then be regenerated to produce a fresh batch of etching solution.

Abstract: The gas burner according to the invention has a burner chamber housing, a mixing pipe connected to the burner chamber housing for supplying a gas/air mixture, a burner plate made of fibrous material and attached to the burner chamber housing at edge regions of the burner plate, a blower for supplying air to make the gas/air mixture, and advantageously an ignition device, a safety device and a temperature monitoring device. A central region of the burner plate is advantageously directly or indirectly connected to a corresponding central region of the burner chamber housing to suppress burner plate vibration during start-up of burner operation to prevent sound generation during the start-up and minimize the pressure drop in the burner chamber.