Verfahren und Vorrichtung zur Bereitstellung eines Volumens einer Substanz

摘要

The invention pertains to a process and device for feeding a predetermined quantity of a test substance (H2) into a monitoring line (2) filled with a test medium (such as air) and used for determining concentration profiles along a given path. In order to move a column of the test medium through the monitoring line (2), the pressure (p) in the monitoring line (2) is raised by actuating a pressure pump or, for the same purpose in an alternative embodiment, lowered by actuating a suction pump (12). A predetermined metered quantity of the test substance (H2) is released automatically when the pressure (p) in the monitoring line (2) passes a predetermined threshold value. Release of the predetermined metered quantity of the test substance (H2), once the latter has been carried by the test medium column, results in a test-peak in a sensor (11) which reacts to the test substance (H2) and is connected to the monitoring line (2). Application: pneumatically controlled test-peak generator.