395 research outputs found
Glass Ceramics Composites Fabricated from Coal Fly Ash and Waste Glass
Great quantities of coal ash are produced in thermal power plants which present a double problem to the society: economical and environmental. This waste is a result of burning of coal at temperatures between 1100-14500C. Fly ash available as fine powder presents a source of important oxides SiO2, Al2O3, Fe2O3, MgO, Na2O, but also consist of small amount of ecologically hazardous oxides such as Cr2O3, NiO, MnO. The combination of the fly ash with waste glass under controlled sintering procedure gave bulk glass-ceramics composite material. The principle of this procedure is presented as a multi barrier concept (1). Many researches have been conducted the investigations for utilization of fly ash as starting material for various glass–ceramics production (2-4). Using waste glass ecologically hazardous components are fixed at the molecular level in the silicate phase and the fabricated new glass-ceramic composites possess significantly higher mechanical properties.
The aim of this investigation was to fabricate dense glass ceramic composites using fly ash and waste glass with the potential for its utilization as building material
Requirements of the authorized examinator physician (AME) for class II: interpretative doubts and suggestions
The purpose of this document is to clarify the requirements
that a doctor must have for carrying
out the Authorized Examiner (AME) activity for
class II workers.
We have consulted the normative sources that indicate
the requisite that the authorized physicians
must possess and subsequently we have compared
the norms, the European Union regulations
and the national ones issued by the National Civil
Aviation Body (ENAC), as well as the guidelines
indicated by the EASA.
Finally, Authors give suggestions that can be given
to ENAC regarding the issue of the authorization
as AME examiner for class II workers
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