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By exploiting the interferometric antireflection action of a probe sample, consisting of a diamond-like carbon (DLC) film grown on Si, combined with a specific illumination spectrum, we designed and constructed an optical device for the visual remote sensing of radiation (either plasma or atomic oxygen) and for the visual inspection of adsorbed organic contamination as thin as a few molecular layers. The capabilities of this new visual interferometric multi-indicator (VIMI) enable the bare-eye color detection of thickness changes on the order of a few nanometers without the intervention of any instrumental or computer interface.

Determining the thermal conductivity of a material from temperature measurements in a cooling or heating process belongs to the class of inverse problems. In this article we present a method for a simple experimental setup, consisting of a glass tube containing the material under investigation, two thermistors for temperature monitoring (one at the central axis and the other attached on the outer surface of the tube) and a water heat bath maintained at a desired temperature. We solve the direct problem, i.e. the transient heat conduction equation, treating the thermal conductivity as a parameter whose value is determined by minimizing the difference between the calculated and the experimentally measured temperatures. The method is based on the numerical solution of the one dimensional transient heat conduction equation in cylindrical coordinates that accurately describes the temperature evolution of a material in a narrow, long glass tube. The technique has been validated by applying it to the Lauric and Capric acids, whose thermal conductivities are accurately known and therefore it could be a valuable tool for the determination of the thermal properties of phase change materials suitable for thermal storage applications.