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In this paper the application of DSPI to diffusion evaluation in liquid binary mixtures is discussed. The interdisciplinary nature of the proposed technique is outlined by emphasizing its connections with electronics, digital image processing and numerical analysis. An extensive simulation of the procedure and preliminary experimental results are presented.

A laser speckle technique is proposed for the study of diffusion in transparent liquid mixtures. The diffusion constants may be deduced by a simple manipulation of the speckle patterns recorded during the diffusion process. The proposed method, checked with the LiBr-water system, gives reasonable agreement with existing data

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In this work we use the unusual behaviour of a light beam in a diffusion cell as an experimental introduction for university students of physics and engineering to the optical - mechanical analogy. We have found that the lecture demonstration is a key element in the development of the presentation and subsequent use of the analogy. Riassunto. In questo lavoro si utilizza l'inusuale comportamento di un fascio luminoso in una cella di diffusione come introduzione sperimentale, per studenti di fisica e di ingegneria, all'analogia tra il comportamento di una particella materiale ed un fascio luminoso (Analogia di Hamilton). La dimostrazione didattica rappresenta un elemento chiave nello sviluppo della presentazione e del successivo utilizzo dell'analogia.

A system based on TV holography is proposed for measuring the free convection heat transfer coefficient of a heated metal plate. The aim of this experiment is to familiarize university students of physics and engineering with the practical applications of optical techniques to heat transfer.

This work provides a general tool for accurate multidimensional transient analysis by means of polynomial heat conduction transfer functions (CTF) which are valid for the whole class of objects having the same geometric shape. With this aim the governing conduction equations were turned into dimensionless variables, such as the well known Biot number (Bi) and Fourier modulus (Fo), and thereafter handled through a finite-element technique to create the CTF with respect to any arbitrary point of the conductive field. In addition, by selecting the nondimensional time interval (ΔFo) according to the sampling theorem, i.e., as a function of Bi, the CTF were scheduled in the form of one-entry tables. The Bi incremental values were furthermore assessed to provide, for any input function, temperature histories within equal percent deviations, say 10 percent. Since for many purposes a five percent tolerance will usually suffice, the CTF tables can be used without the necessity of interpolating. As an example, generalized CTF tables are presented for the central and one of the corner points of a cube.

An image processing system to analyze interference patterns, related to the measurement of diffusion coefficient of liquid binary mixtures by sandwich holography, is proposed. Basic image processing tools are used and a specific software has been developed to perform an automated analysis of interferometric data. An example of application of this electrooptical method to the measurement of the diffusion coefficient of LiBr is reported