Curtain-type coater and process for coating a web with curtain-type coater. The connector has an adaptor plate that is substantially circular and has one or more radially outwardly projecting flanges and is arranged to be inserted into a ring-shaped engagement member having one or more openings in a front cover. In several of the embodiments of the invention, apparatus utilized in the methods permit convenient retrieval of samples of the formation fluids and provide enhanced data acquisition for monitoring of the test and for evaluation of the formation fluids. The invention is applied to medical or industrial tomography methods and is of larger interest for mobile objects, the movement of which may be estimated and compensated. It is preferable to use the clamping member coated by solder. A plurality of process programs in which measurement algorithm is segmentalized are incorporated in the extension unit and a process program is selected according to a command from a personal computer and the selected process program is performed in a predetermined order.