Abstract: Systems and methods include a method for determining the purity of a sample. An image capture is performed of a reference material having a known purity and an unknown material having an unknown purity for which a priori information is known, including that the reference material and the unknown material have a same material type. An image comparison of the reference material and the unknown material is performed to determine a color difference vector between an image of the reference material and an image of the unknown material. A purity of the unknown material is determined using the color difference vector.

Abstract: The present invention regards a fin for a finned pack for heat exchangers, including a plate in which a plurality of through holes is formed for the positioning of tubes intended to convey a first heat exchange fluid, the plate having an edge as well as two main faces, each intended to be licked by a second heat exchange fluid in a crossing direction (A-A) from an inlet portion to an outlet portion of the edge of the plate.