In this work, heat trials (14 heats made on two sequences) were conducted to identify the minimum Ca addition possible for preventing submerged entry nozzle clogging and for improving the steel Cleanness. These trials were conducted on two sequences, the first one aimed at reaching the minimum Ca addition practically possible and the second aimed at stabilising this addition level. Evaluation of the results was carried out using metallographic microscope observation and SEM/EDX analysis. It was found that submerged entry nozzle clogging was successfully prevented by decreasing the amount of Ca addition from 0?095 to 0?06 kg Ca/ton steel. Moreover, it was possible to identify the effect of such addition level on converting alumina inclusions to globular Ca-aluminate and reducing the CaS inclusion formation range from 4-41 to 0?05-7?61%.

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Historical textiles suffer from deterioration as a result of exposure to uncontrolled environmental conditions in museums. To establish standard conditions for display of undyed and dyed silk fabrics in Egyptian museums, different artificial aging procedures (thermal, light and chemical) were applied to examine their effects on the physical, mechanical and chemical structure of the silk fiber. Samples of undyed silk and silk dyed with madder with different mordants, iron II sulphate; iron III chloride and copper sulphate were used for this purpose. These aged samples were examined for their surface morphology, color parameters (CIE Lab), mechanical properties, degree of crystallinity, secondary structure analysis and amino acids content.