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This paper aims to evaluate of silica and alumina nanocomposites in consolidation and protection of archaeological glass from early Islamic period in Egypt. Archaeological glass is exposed to deterioration by moisture, as water is considered one of the most dangerous damage factors that attack glass artifacts. This results in many aspects of deterioration including weeping glass, cracks, dulling, formation of weathering crusts, salt growing, and corroded surfaces. From this standpoint, materials which are used in the consolidation and protection of those glass artifacts must have the property of hydrophobicity in order to protect them from the harmful effects of water. In the last decade, polymer-nanoparticle composites have attracted great interest in the field of culture heritage conservation due to their unique multifunctional properties resulting from the high surface area and chemical activity of the nanoparticles dispersed in the polymers. In this study, Silicon dioxide (SiO2) and alumina oxide (Al2O3) nanoparticles are added to silicon based polymer (poly alkyl siloxane) (Silres BS-290) in order to improve their physiochemical and mechanical properties. This produced a significant improvement in the ability of the polymers to consolidate and protect archaeological glass. The treated samples are exposed to artificial ageing to test the efficiency of the consolidation materials. The properties of untreated, treated and aged glass samples were evaluated by TEM, stereo microscope, scanning electron microscope (SEM), colormetric measurements, static water contact angle, density and hardness tests (physical and mechanical properities). Results showed that the treated sample with SiO2/Al2O3/Poly siloxane nanocomposites are good candidates for consolidation and protection of glass objects. [ABSTRACT FROM AUTHOR]

Faba bean is amang the most strategic crops in Egypt and suffering from many destructive diseases especially chocolate spot caused by Botrytis fabae Sard. which can reduce yield production. Effect of chitosan nanoparticles (ChNPs) and silver nanoparticles (AgNPs) with average particle size of 7.54 and 8.043 nm, respectively at five concentrations (20, 40, 60, 80 and 100 ppm), as well as recommended dose of carbendazim (CZ) 100 g/100L (field rate) were studied in vitro against aggressive isolate of Botrytis fabae (B.f4). All concentrations significantly inhibited the radial growth of B.f4 compared with the control treatment. In vitro results showed that ChNPs followed by AgNPs were effective over conventional chemical fungicide CZ. Where the radial growth of B.f4 decreased by increasing concentration of the different materials especially ChNPs at 20-40 ppm recording 73.33% and 100% growth inhibition, respectively. While 100 ppm of AgNPs and recommended dose of CZ rate of 75.33% and 46.11% growth inhibition, respectively. In addition, scan electron microscope (SEM) showed that, the mycelium of B.f4 treated by AgNPs did not have detruation changes at 20 ppm. Contrary to B.f 4 mycelia treated with ChNPs 20 ppm exhibited seriously shrunk after 72 h post treatment in relative to the control. The antifungal effect of ChNPs, showed marked covered distorted mycelia. Most B.f4 spore morphology treated with AgNPs 20 ppm appeared to be shrunk and abnormal shape 72 h post treatment compared with the control. In addition, AgNPs lead to deforming B. fabae spores and explosion of others. On the other hand, spore production of B. fabae treated with ChNPs 20 ppm was completely inhibited 72 h post treatment. The obtained results offers a possibility of developing new manufacturing fungicides using chitosan and silver nanoparticles as substances for save control of faba bean chocolate spot disease and minimize the impact of conventional fungicides in the agri-ecosystem. [ABSTRACT FROM AUTHOR]