The aim of this study is to examine and present the results of the scientific examinations carried out on the ground layers with paint samples collected from the decorated surfaces of the wooden coffin dated back to t...The aim of this study is to examine and present the results of the scientific examinations carried out on the ground layers with paint samples collected from the decorated surfaces of the wooden coffin dated back to the late period from Saqqara excavation that belonged to the Ministry of Antiquities. Many analytical methods were performed as optical microscopy, scanning electron microscopy coupled with energy-dispersive X-ray analysis （ESEM-EDX）, X-ray diffraction analysis as well as fourier transform infrared spectroscopy have been used to both characterise the inorganic composition and the binding media used. The analytical results showed that the materials composition and technique used to plaster applied on the wooden surface are in good agreement with the information gathered through the historical survey. The coffin was in bad and poor condition. There was cracking on the surface and in the structure, serious flaking, cupping of some pigments and serious damage in both the wooden support and gesso layer. Conservation treatment processes carried out included consolidation of lifting areas of the paint film, disturbing restoration materials, repair of cracks in the wooden support and a dry surface cleaning of the pigments.展开更多
The influence of Zr content on corrosion behaviors of the Ni61.5Nb 38.5xZrx(x=1,3,5,7,9 at.%) bulk metallic glasses(BMGs) in 1 M HCl aqueous solution was investigated by potentiodynamic polarization measurements and X...The influence of Zr content on corrosion behaviors of the Ni61.5Nb 38.5xZrx(x=1,3,5,7,9 at.%) bulk metallic glasses(BMGs) in 1 M HCl aqueous solution was investigated by potentiodynamic polarization measurements and X-ray photo-electron spectroscopy(XPS).It was found that these BMG alloys possess superior corrosion resistance,that is,with large passive region of about 1.5 V and low passive current density(as low as 0.05 Am-2 for Ni61.5Nb31.5Zr7).XPS analysis indicates that the high corrosion resistance is attributed to the formation of Nb-and Zr-enriched surface films formed in the aggressive acid solution.The Zr substitution for Nb effectively reduces the Ni content,particularly the metallic state Ni content in the surface films,which depresses the electrical conduction of the surface films and reduces the passive current density,thus leading to the enhancement of the corrosion resistance of these Ni-Nb-Zr BMGs.These alloys may potentially be useful for engineering applications.展开更多
文摘The aim of this study is to examine and present the results of the scientific examinations carried out on the ground layers with paint samples collected from the decorated surfaces of the wooden coffin dated back to the late period from Saqqara excavation that belonged to the Ministry of Antiquities. Many analytical methods were performed as optical microscopy, scanning electron microscopy coupled with energy-dispersive X-ray analysis （ESEM-EDX）, X-ray diffraction analysis as well as fourier transform infrared spectroscopy have been used to both characterise the inorganic composition and the binding media used. The analytical results showed that the materials composition and technique used to plaster applied on the wooden surface are in good agreement with the information gathered through the historical survey. The coffin was in bad and poor condition. There was cracking on the surface and in the structure, serious flaking, cupping of some pigments and serious damage in both the wooden support and gesso layer. Conservation treatment processes carried out included consolidation of lifting areas of the paint film, disturbing restoration materials, repair of cracks in the wooden support and a dry surface cleaning of the pigments.
基金supported by the National Natural Science Foundation of China(Grant Nos.50825402 and 50731005)the National Basic Research Program of China(Grant No.2011CB606301)
文摘The influence of Zr content on corrosion behaviors of the Ni61.5Nb 38.5xZrx(x=1,3,5,7,9 at.%) bulk metallic glasses(BMGs) in 1 M HCl aqueous solution was investigated by potentiodynamic polarization measurements and X-ray photo-electron spectroscopy(XPS).It was found that these BMG alloys possess superior corrosion resistance,that is,with large passive region of about 1.5 V and low passive current density(as low as 0.05 Am-2 for Ni61.5Nb31.5Zr7).XPS analysis indicates that the high corrosion resistance is attributed to the formation of Nb-and Zr-enriched surface films formed in the aggressive acid solution.The Zr substitution for Nb effectively reduces the Ni content,particularly the metallic state Ni content in the surface films,which depresses the electrical conduction of the surface films and reduces the passive current density,thus leading to the enhancement of the corrosion resistance of these Ni-Nb-Zr BMGs.These alloys may potentially be useful for engineering applications.
