Abstract. Tourmaline solid solutions containing Fe, Fe + Ti, Cr, Ni, Cu, Co, Mn chromophoric centers have been grown hydrothermally at 650 ~ C and 1,5 kbar on natural seeding plates close to the elbaite composition. The newly grown tourmalines were characterized by chemical analyses and optical absorption spectroscopy in the range 26316-5000 cm -x at 297 K and in the range 26 316 --9090 cm-1 at 77 K. Most characteristic of Fe / +, Fe 3 +-bearing specimens is the presence of intensive apolarized absorption bands caused by exchange-coupled FeZ+-Fe 3+ pairs in Y-and Z-sites of the tourmaline structure. An additional intensive absorption band 12 500 cm-1 (a-polarisation) appears in some specimens but is not yet found in spectra of natural tourmalines. The colour and spectroscopic properties of the Fe 3+, Mn 3 + and Cu / + containing tourmalines are significantly affected by the presence of even the smallest Li-contents. The results suggest that Fe / +, Cu 2 +, Co z +, Ni 2 +-ions occupy, predominantly, Y-sites of the tourmaline structure, whereas the Cr3+-ions seem to enter the smaller Z-octachedra.B atoms in triangular coordination, linked to the vertices of the Y-Z octahedra. The "clusters" are attached to one another by Z octahedra, to results in a screwlike arrangement.Extensive substitutions in the Y, Z octahedra and in the large cation sites X give rise to the tourmaline solid solution series with hypothetical end members. (elbaite-liddicoatite) Ca / + (X) + Mg 2 + (Z) -,Na + (X) + A13 + (Z) (uvite-dravite) Na + (X) + 0 2 -~ u(X) + OH-(proton-loss -alkalibuergerite)

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The satisfactory explanation of abnormal electromagnetics in thin graphite-like carbon films till now is absent. The most comprehensible explanation may be the high-temperature superconductivity (HTSC). Times of spasmodic switching of electrical conductivity are measured in this work in graphite-like nanostructured carbon films, produced by methods of the carbon arc (CA) and chemical vapor deposition (CVD), which have made 1 and 2 nanoseconds correspondingly. So fast switching completely excludes the thermal mechanism of the process. According to HTSC logic, in the time vicinity close to jump of electroresistance it is necessary to expect the generation of optical radiation in infrared (IR) range. This work presents the first results on registration of IR radiation caused by sharp change of conductivity in thin graphite-like carbon films.

The problems of stripper target behavior in the nonstationary intense particle beams are considered. The historical sketch on studies of radiation damage failure of carbon targets under ion bombardment is presented. The simple model of target evaporation under intensive pulsing beam is supposed. Lifetimes of stripper targets under intensive nonstationary beams can be described by two failure mechanisms: radiation damage accumulation and evaporation of a target. At the maximal temperatures less than 2500 K the radiation damage dominates; at temperatures above 2500 K the mechanism of evaporation of a foil prevails. The proposed approach has been applied to the description of stripper foils behavior in Brookhaven National

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