Abstract: A method for operating a drive system (10) of an electric vehicle, comprising a first energy source (21), a second energy source (22) formed as an electrical energy store, and at least one electric machine (30) is disclosed. In a first operating mode, electrical energy is transferred from the first energy source (21) to at least one electric machine (30), and electrical energy is transferred from the second energy source (22) to at least one electric machine (30). In a second operating mode, electrical energy is transferred from the first energy source (21) to at least one electric machine (30), and electrical energy is transferred from at least one electric machine (30) to the second energy source (22).

Abstract: A method for operating a drive system (10) of an electric vehicle, comprising a first energy source (21), a second energy source (22) formed as an electrical energy store, and at least one electric machine (30) is disclosed. In a first operating mode, electrical energy is transferred from the first energy source (21) to at least one electric machine (30), and electrical energy is transferred from the second energy source (22) to at least one electric machine (30). In a second operating mode, electrical energy is transferred from the first energy source (21) to at least one electric machine (30), and electrical energy is transferred from at least one electric machine (30) to the second energy source (22).

Abstract: A sample plate, portable analysis apparatus and method of analysing sulphur and/or nitrogen compounds in a sample fluid, the method comprising feeding a sample fluid to a sample plate having a sample inlet, a reaction zone, an analysis zone, and at least one separation zone, the sample plate being adapted to allow; (a) a sample fluid to be fed to the sample plate through the inlet to the reaction zone or optionally to a separation zone, which separation zone separates the sample fluid into two or more fractions at least one of which is fed to the reaction zone; (b) a reactant to be fed to the reaction zone; (c) the reaction zone to be maintained under conditions that enable reaction to occur between the reactant and the sample fluid or fraction thereof to produce a product fluid; and (d) transfer of the product fluid to the analysis zone or optionally to a separation zone in which the product fluid is separated into two or more fractions, at least one of which is transferred to the analysis zone.