Abstract: Removal of heat generated by IT equipment in a data centre is facilitated by heat changing units mounted to back sides of open computer storage racks in which the IT equipment is mounted. One or more fans in the IT equipment generate an air flow across the IT equipment, and a heat exchanging unit mounted to the back side of the rack transfers heat in the air flow to a fluid coolant flowing through the heat exchanging unit. The heat exchanging unit has an air back pressure that does not significantly impede the air flow across the IT equipment, and a low fluid pressure drop for the fluid coolant, so that a cold air exhaust temperature of air exiting the heat exchanging unit is less than or equal to the room air temperature of input air entering the computer rack.

Abstract: Removal of heat generated by IT equipment in a data centre is facilitated by heat exchanging units mounted to back sides of open computer storage racks in which the IT equipment is mounted. One or more fans in the IT equipment generate an air flow across the IT equipment, and a heat exchanging unit mounted to the back side of the rack transfers heat in the air flow to a fluid coolant flowing through the heat exchanging unit. The heat exchanging unit has an air back pressure that does not significantly impede the air flow across the IT equipment, and a low fluid pressure drop for the fluid coolant, so that a cold air exhaust temperature of air exiting the heat exchanging unit is less than or equal to the room air temperature of input air entering the computer rack.

Abstract: The present invention relates to a method for operating a data centre, which is adapted to house a multiplicity/plurality of racks being designed to provide storage space for IT equipment. The data centre is equipped with cooling means in order to provide dissipation of heat being generated by the IT equipment. Data centre operated according to the present invention have a power utility efficiency (PUE) of at most 1.3, preferably at most 1.2, more preferred at most 1.15, in particular at most 1.1.

Abstract: A method for texturing surfaces of silicon wafers comprising the steps of dipping the silicon wafers in an etching solution of water, concentrated hydrofluoric acid and concentrated nitric acid and setting a temperature for the etching solution. The etching solution comprises, in percent, 20% to 55% water, 10% to 40% concentrated hydrofluoric acid and 20% to 60% concentrated nitric acid and the temperature of the etching solution is between 0 and 15 degrees Celsius.

Abstract: In a method for texturing surfaces of silicon wafers comprising the steps of dipping the silicon wafers in an etching solution of water, concentrated hydrofluoric acid and concentrated nitric acid and setting a temperature for the etching solution, it is provided that the etching solution comprises, in percent, 20% to 55% water, 10% to 40% concentrated hydrofluoric acid and 20% to 60% concentrated nitric acid and that the temperature of the etching solution is between 0 and 15 degrees Celsius. This results in a comparatively higher efficiency due to reduced reflection by the silicon wafers.