Surface Preparation of Alumina for Improved Adhesive Bond Strength in Armor Applications
Surface treatments of alumina have been investigated with the aim of increasing the strength of the bond created between the alumina and a toughened epoxy adhesive. Four surface conditions have been assessed: as-fired; grit blasted; and krypton fluoride excimer laser treated under two sets of conditions. Compared with the as-fired surface, the grit blasted surface was rougher with poorer wettability, probably due to surface contamination. It was found that the laser treatments removed some of the sintering additives and caused rounding of the alumina grains, slightly increasing the surface roughness. Further, the laser treatment led to an increased surface energy and wettability, which has been linked tentatively to an observed increase in the hydroxyl groups on the surface. The adhesive bond strength was assessed by testing joints in tension and shear. It was found that the laser treated surfaces demonstrated slight improvements in bond strength, with a cohesive failure of the adhesive in tension for surfaces subjected to one of the two laser treatments, compared with failure at the interface for the as-fired, grit blasted and other laser treated samples in tension and for all samples in shear. Thus, it has been demonstrated that modifications to the surface of alumina can result in mechanical and chemical changes which affect roughness, wettability, bond strength and the locus of failure.
Surface treatment of alumina ceramic for improved adhesion to a glass fibre-reinforced polyester composite
Lausund, Kristian Blindheim; Johnsen, Bernt Bronmo; Rahbek, Dennis Bo; Hansen, Finn Knut. 
Surface treatment of alumina ceramic for improved adhesion to a glass fibre-reinforced polyester composite. International Journal of Adhesion and Adhesives 2015 ;Volum 63. s. 34-45
Heritage Sites of Astronomy and Archaeoastronomy in the context of the UNESCO World Heritage Convention: A Thematic Study
"Following the publication of the first ICOMOS–IAU Thematic Study (“TS1”) in 2010, the IAU requested its Working Group on Astronomy and World Heritage to develop particular case studies in greater detail, so as to explore further and clarify some of the key issues highlighted in TS1 that can arise in the particular case of astronomical heritage sites. In doing so, it would further encourage and aid State Parties in the development of nominations. In collaboration with ICOMOS, nine “extended case studies” were duly prepared for discussion at a workshop held at Mount Cook, New Zealand, in June 2012 and presented at the IAU General Assembly in August of that year. 
 
A particularly complex issue is the recognition and protection of dark skies. Dark sky areas cannot in themselves be considered as potential World Heritage Sites, but a thematic chapter by Michel Cotte considers a range of ways in which dark sky values can be interrelated with broader cultural or natural values of a place and thereby contribute to its overall cultural or natural value and potential OUV. Other issues explored in TS2 include the need to balance archaeoastronomical considerations in the context of broader archaeological and cultural values; the potential for serial nominations, for example among groups of monuments whose astronomical significance is only evident from the group as a whole; and management issues such as preserving the integrity of astronomical sightlines through the landscape. 
 
The case studies included in TS2 include seven-stone antas (prehistoric dolmens) in Portugal and Spain, the thirteen towers of Chankillo in Peru, the astronomical timing of irrigation in Oman, Pic du Midi de Bigorre Observatory in France, Baikonur Cosmodrome in Kazakhstan, and Aoraki–Mackenzie International Dark Sky Reserve in New Zealand. A case study on Stonehenge, already a World Heritage Site, focuses on preserving the integrity of the solstitial sightlines." 
 
Source: UNESCO portal to the heritage of astronomy