Abstract: There is disclosed a solar energy control film and a siding panel to which such film is applied, the film having a multiplicity of lenticular lenses formed on one side thereof which are preferable about one-tenth to one millimeter wide and having on the surface opposite to that with the lenticular lenses an array of masking indentations in register with the lenticular lenses so that the film is effectively transparent for the passage of light (solar radiation passing through to an absorbing heat collector) only for rays impinging on a structure at prescribed elevation angles. Typically the masking indentations would be arranged to pass light at a low elevation angle corresponding to wintertime solar elevation at the latitude at which the structure is located. In particular embodiments, the indentations in the film are rendered non-transparent by being filled with a liquid or semi-liquid material including pigments or dyes to impart opacity, and in most cases reflectivity, to the material.

Abstract: An apparatus and a method to remove and collect ferrous particles from a fluid for ferrous particle analysis. In one embodiment, the apparatus includes a holder chamber and a removable examination slide within the chamber. A magnet induces a magnetic field at the examination slide. A portion of the fluid is passed over the slide in order for the magnetic field to retain ferrous particles on the slide. Thereafter, the slide can be removed from the holder chamber for ferrographic analysis.