Abstract: A lidar device having a light source, a detector, and a mirror device. The light source has a main radiation direction and the detector has a main detection direction. The mirror device is rotatable about an axis and has a facet wheel with a number of facets. The main radiation direction and the main detection direction stand at a predetermined angle to each other, the predetermined angle being a function of the number of facets. A light beam emitted from the light source is reflected by a first facet and a light beam reflected back from an object is reflected by a second facet. Here the first facet and the second facet are different.

Abstract: The invention relates to a zoom objective lens with continuously adjustable magnification, comprising five lens groups, where the first lens group, the second lens group and the fifth lens group are fixed in relation to an object. The third lens group and the fourth lens group are axially displaceable. The following conditions apply to the lens: the variable air gap between the second lens group and the third lens group decreases or has a turning point with a transition from a low to a high magnification ?, the refractive power of the second, third and fifth lens groups is positive and the refractive power of the fourth lens group is negative.

Abstract: A method for preparing a fuel cell system for a starting operation involves performing a start preparation routine when switching off of the fuel cell system and/or when the temperature falls short of a predetermined temperature threshold value in order to discharge water and moisture from the fuel cell system. The start preparation routine is changed in accordance with measured values detected within a predetermined time interval before the stopping of the fuel cell system.

Abstract: The invention relates to a zoom objective lens with continuously adjustable magnification, comprising five lens groups, where the first lens group, the second lens group and the fifth lens group are fixed in relation to an object. The third lens group and the fourth lens group are axially displaceable. The following conditions apply to the lens: the variable air gap between the second lens group and the third lens group decreases or has a turning point with a transition from a low to a high magnification ?, the refractive power of the second, third and fifth lens groups is positive and the refractive power of the fourth lens group is negative.

Abstract: A fuel cell system includes at least one fuel cell and a humidifying device for humidifying a supply air flow flowing to a cathode chamber of the fuel cell by an exhaust air flow discharged from the cathode chamber of the fuel cell. The supply air flow and the exhaust air flow are separated from one another by water vapor-permeable membranes. An anode water separator, through which exhaust gas from an anode chamber of the fuel cell flows, is integrated into the humidifying device.

Abstract: An immersion objective for a light microscope with a first lens group including a first and second lenses, with a third lens arranged behind the first lens group, a first air gap between the first lens group and the third lens, with a second lens group behind the third lens and including fourth, fifth and sixth lenses, a second air gap formed the third lens and the second lens group, and a third lens group behind the second lens group including seventh, eighth and ninth lenses. Tenth, eleventh and twelfth lens are provided behind the third lens group. For correction of aberrations a fourth air gap is formed between the third lens group and the tenth lens, a fifth air gap is formed between the tenth lens and the eleventh lens and a sixth air gap is formed between the eleventh lens and the twelfth lens.

Abstract: A method for preparing a fuel cell system for a starting operation involves performing a start preparation routine when switching off of the fuel cell system and/or when the temperature falls short of a predetermined temperature threshold value in order to discharge water and moisture from the fuel cell system. The start preparation routine is changed in accordance with measured values detected within a predetermined time interval before the stopping of the fuel cell system.

Abstract: A fuel cell system includes at least one fuel cell, line elements for supplying and discharging starting materials and/or products to/from the fuel cell, and at least one condensation unit. The condensation unit is situated in at least one of the line elements and, at least in individual operating phases of the fuel cell, the condensation unit is at a lower temperature level than the areas surrounding it and the fuel cell.

Abstract: A fuel cell system includes at least one fuel cell and a humidifying device for humidifying a supply air flow flowing to a cathode chamber of the fuel cell by an exhaust air flow discharged from the cathode chamber of the fuel cell. The supply air flow and the exhaust air flow are separated from one another by water vapor-permeable membranes. An anode water separator, through which exhaust gas from an anode chamber of the fuel cell flows, is integrated into the humidifying device.

Abstract: An immersion objective for a light microscope with a first lens group including a first and second lenses, with a third lens arranged behind the first lens group, a first air gap between the first lens group and the third lens, with a second lens group behind the third lens and including fourth, fifth and sixth lenses, a second air gap formed the third lens and the second lens group, and a third lens group behind the second lens group including seventh, eighth and ninth lenses. Tenth, eleventh and twelfth lens are provided behind the third lens group. For correction of aberrations a fourth air gap is formed between the third lens group and the tenth lens, a fifth air gap is formed between the tenth lens and the eleventh lens and a sixth air gap is formed between the eleventh lens and the twelfth lens.

Abstract: A fuel cell system includes an anode circuit by means of which unused gas from the anode region of a fuel cell can be recirculated via a recirculation delivery device into the anode region. At least one liquid separator is provided in the anode circuit. The liquid separator is integrated with the recirculation delivery device to form an assembly. Fresh hydrogen is supplied to the anode region by feeding the hydrogen into the liquid separator.

Abstract: A method serves for operating a fuel cell system with at least a fuel cell and a feed air side air conveyor and an outgoing air side turbine. The fuel cell system is flushed at least during a switching-off procedure with air from the air conveyor. During flushing a connection is created between the air conveyor and the outgoing air side between the fuel cell and turbine.

Abstract: A cooling device for a fuel cell system includes at least one cooling circuit, through which a fuel cell can be cooled. The fuel cell system also includes a component with at least an electric drive area and a gas delivery area. A gas can be delivered to the fuel cell through the gas delivery area and the component is actively cooled. The cooling of the component takes place together with the cooling of the fuel cell in a cooling circuit.

Abstract: A method of operating a fuel cell system with at least one fuel cell unit comprising a plurality of fuel cells, each having one anode and one cathode, the anode adjoining an anode gas compartment and the cathode adjoining a cathode gas compartment, hydrogen being supplied to the anode and an oxidizing agent being supplied to the cathode. Hydrogen is supplied to the anode compartment during a retention time before start-up of the fuel cell system, in which no fuel cell reaction takes place in the fuel cell unit. Hydrogen is stored in an adsorption storage element during fuel cell operation and released to the anode compartment during the retention time.

Abstract: A method of ceasing operation of a fuel cell system comprises terminating a supply of a hydrogen-containing fuel to a fuel cell stack, drawing a potential of the fuel cell stack to a load to substantially consume hydrogen in the fuel cell stack, introducing a dose of air to at least a portion of anode electrode layers from at least one of an air supply source and an external source, and reacting hydrogen and oxygen in the anode electrode layers to consume substantially all the hydrogen remaining in the fuel cell stack.

Abstract: A fuel cell system having at least one fuel cell, which possesses one anode area as well as one cathode area that is separated from the anode area by an electrolyte. The anode area and the cathode area each contain one catalyst for the catalytic conversion of reactants being supplied to the fuel cell. During downtime periods of the fuel cell, the anode area is filled with air or oxygen. Provided in the area of an inlet and/or in the area of an outlet of the anode area is an additional catalyst for the catalytic conversion of hydrogen with oxygen, which is set up to catalytically convert hydrogen diffusing towards the anode area during downtime periods of the fuel cell when the anode area is filled with air or oxygen.