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Both 2,5-bis-2(l-naphthyl)vinylpyrazJne (BNVP) and 2,5-bis-2(2-naphthyl)vinylpyrazine (B2NVP) diolefinic dyes have relatively short excited-state lifetimes, high fluorescence efficiencies and low photochemical quantum yields. BNVP solutions in dimethyl formamide and methylene chloride give amplified spontaneous emission (ASE) with a maximum at 500 nm. The low solubility of B2NVP in organic solvents does not allow the measurement of ASE for this dye. The excited state absorption spectra (ESA) of BNVP show an absorption band around 525 nm which reduces dye laser efficiency. Energy transfer from 7-diethylamino-4-methylcoumarin to BNVP and B2NVP has been studied by applying Stern-Volmer plots. The underlying mechanism is a radiative long range energy transfer. Both BNVP and B2NVP undergo solubilization in anionic as well as cationic micelles.

Steady state current-potential curves for the anodic dissolution of zinc in aqueous-methanolic 0.25M trichloracetic acid solutions were constructed for wide ranges of the solution composition and temperature. Analysis of the results reveal that the increase of the water content and rise of temperature of the solution increases the corrosion rate. The most plausible role of the solvent lies within the stabilization of the anodic dissolution reaction products by water molecules. The changes in the properties of the solution due to the presence of methanol which give rise to hindrance of the anodic dissolution reaction are adsorption of methanol, change of viscosity and pH of the solution. These factors seem to be of secondary importance.

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