Abstract: An apparatus for deriving data concerning the electro-chemical characteristics of a plurality of individual electro-chemical cells or corrosion processes is disclosed. In one aspect, the apparatus includes means for temporarily applying across a cell or a process a controlled multi-frequency electrical signal; means for detecting returned data resultant from said application, and means for utilizing the returned data with to resolve the data into at least three of its electro-chemical constituents, including a series metallic resistance, an electro-chemical resistance, and a double-layer capacitance.

Abstract: A method for aligning an optical element of an optical interferometer in which a beam of light interacts with the optical element and the optical element is tilted about first and second axes to adjust the relative phase of components of the beam. At least three parallel alignment beams of monochromatic light are directed through the interferometer towards respective detectors. The detectors are arranged in pairs such that tilting the optical element about the first axis does not affect the relative phase of components of each of the beams directed towards a first pair of detectors and tilting the optical element about the second axis does not affect the relative phase of components of each of the beams directed towards the second pair of detectors. One detector may form part of each of the first and second pairs of detectors.

Abstract: An apparatus for deriving data concerning the electro-chemical characteristics of a plurality of individual electro-chemical cells or corrosion processes is disclosed. In one aspect, the apparatus includes means for temporarily applying across a cell or a process a controlled multi-frequency electrical signal; means for detecting returned data resultant from said application, and means for utilizing the returned data with to resolve the data into at least three of its electro-chemical constituents, including a series metallic resistance, an electro-chemical resistance, and a double-layer capacitance.