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The NEMO.RD Project is a feasibility study of a km 3 underwater telescope for high energy astrophysical neutrinos to be located in the Mediterranea Sea. At present this study concerns: i) Monte Carlo simulation study of the capabilities of various arrays of phototubes in order to determine the detector geometry that can optimize performance and cost; ii) design of low power consumption electronic cards for data acquisition and transmission to shore; iii) feasibility study of mechanics, deployment, connection and maintenance of such a detector in collaboration with petrol industries having experience of undersea operations; iv) oceanographic exploration of various sites in search for the optimal one. A brief report on the status of points i) and iv) is presented here.

The Ginzburg's «generalized jellium» model of the proximity effect in superconductor-dielectric systems is tested against a wide phenomenology occurring in formvar-metal multilayers. The experimental evidence gained from enhanced superconductivity, critical magnetic fields, energy gap and pair-breaking parameter values seems to support the hypothesis that a formvar eigenfrequency plays the same role as the Debye frequency in setting up the superconductivity of these systems.

Low-energy structures, observed in tunnelling characteristics of Al/formvar/Sn and Al/formvar/Al junctions are reported and discussed. Their connection to tbe vibrational excitation spectrum of the insulator is indicated. Arguments are given to interpret them as excited by an inelastic tunnel mechanism of quasi-holes. A spectroscopic classification of these structures is attempted according to some results previously published. The relevance of these results, obtained for an energy range in which no data from current molecular spectroscopy are available, is stressed.

That an inelastic electron tunneling experiment can be a powerful tool to investigate molecular vibrational spectra was first shown by JAc~VVlC and LAMBE (1). Since that t ime much progress has been accomplished on this field: a fairly up-to-date review can be found in WOLF (2). Tunnel junctions where the insulating barrier is a thin (50--100)• film of Polyvinyl Formate have been extensively investigated by our group in the last few years (3.5). For the reader's opportunity let us briefly summarize the main results that have been obtained. First ly it was shown in (3) that, when the insulating barrier is a Formvar film, proper vibrational modes can be transferred from the metallic electrodes to the

Tunnelling anomalies in Al–formvar–Sn junctions operated at temperatures slightly below the transition temperature of the Al arm, are detected as function of externally applied magnetic fields. Evidence is given to interpret these anomalies as due to the thermodynamic fluctuations of the superconducting order parameter in the Al side. A transverse fluctuation mode appears to be present, in good agreement with the theoretical model proposed by Simanek and Hayward. Nous avons etudie le comportement anomal d'une jonction Al–formvar–Sn a une temperature peu au deseous de quelle de transition de I'electrode de Al, en fonction d'un champ magnetique applie exterieurement. On a mis en evidence I'interpretation des anomalies observees comme dues a les fluctuations thermodynamiques du parametre d'ordre du Al. Nous avons, donc, revele la presence d'un mode de fluctuation transverse, en bon accord avec le modele theorique propose de Simanek et Hayward.

Quantum Size Effects (Q.S.E.) in InSb films have been detected by different experimental procedures. The work function dependence on thickness obtained from photoelectric emission threshold measurements is compared with prior results obtained with the retarding potential method. With both methods, the measured work function values are comparable. They are less than the corresponding bulk values, conforming to current theoretical predictions. The interband energy gap has been determined from photoelectric absorption band edge data: its value differs with respect to the bulk one, by the location of the first allowed energy subband in the conduction band due to the presence of Q.S.E. Some evidence is given for absence of a band structure dependence on Q.S.E.