The synthesis and characterization of Cu-, Al-, Zn-, Ni-, Mn- complexes as substitutes for the Cr- and Co-complex acid azo dyes with lower toxicity was carried out and the subsequent use of ultra-filtration was studied with the aim of purifying the metal complex dyes and thus increasing dye strength and solubility and additionally reducing the free metal present in the final dye. A drastic reduction in the content of inorganic additives and free metal was achieved by the ultra-filtration process. The ultra-filtrated and non-ultra-filtrated dyes were used to dye wool and nylon fabrics. Color measurements and fastness properties were performed on the dyeings produced on wool and polyamide and compared with the Cr-complex dyeing, thus examining the possibility of using successfully these complex dyes as possible replacement of the Cr- and Co-complex dyes.

Forest residue extraction levels in Greece are currently very low, but logging residues have the potential to be an important component of the wood energy supply chain. Forests are a major supplier of renewable energy. Exploring the possibilities of utilizing the biomass of logging residues for energy requires analysis and knowledge of its properties. In this research work the properties (ash, volatiles, fixed carbon, carbon, hydrogen, oxygen, nitrogen and calorific value) of the various constituents of the biomass of fir (Abies borisii - regis), pine (Pinus nigra), oak (Quercus frainetto) and beech (Fagus silvatica) logging residues were determined. Bark and ash content increased with decreasing diameter of branches. Ash content was higher in bark than in wood of branches in all species. Ash and nitrogen content was several times higher in bark and in foliage or needles than in wood of branches. Oak branches and twigs of all species had ash and nitrogen content higher than that required by the EN ISO 17225-2 standard for domestic pellets and they should not be used for energy, at least for pellets production. Volatile mater, fixed carbon, carbon and hydrogen content were in the range given by other researchers. Heating value is higher in softwood (fir and pine) than in hardwood (oak and beech) and ranged from 18.72 MJ/kg to 21.00 MJ/kg. In addition, Duncan's multiple range test was used to compare the means between the various constituents in all species.

The colour and dyeing properties temperature range and rate of dyeing of 14 hetarylazo disperse dyes previously synthesized and applied by exhaustion on cellulose acetate were evaluated visually and instrumentally and the results were compared and reported. A satisfactory agreement between the visual and the instrumental evaluation of these properties was concluded.