Maastricht Economic and social Research and  training centre on Innovation and Technology

 
Master's Open Day at UNU-MERIT
UNU-MERIT will host a Master’s Open Day on Saturday 7 October 2017. Our top-ranked MSc in Public Policy and Human Development (MPP) emphasises the connection between public policy and decision-making processes, as well as the principles of good governance.

Students who successfully complete our Master’s programme receive a double degree issued by the United Nations University and Maastricht University. Several information sessions will be offered throughout the day and visitors will have the opportunity to talk with staff and students.
See: https://www.merit.unu.edu/events/event-abstract/?id=1660



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All headlines
  • Light stored as sound for the first time
  • New method for testing blood with sound waves developed
  • Could we store carbon dioxide as liquid lakes under the sea?
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  • Why modern mortar crumbles, but Roman concrete lasts millennia
    Modern concrete, used in everything from roads to buildings to bridges, can break down in as few as 50 years. But more than 1000 years after the western Roman Empire crumbled to dust, its concrete structures are still standing. Now, scientists have finally figured out why: a special ingredient that makes the cement grow stronger, not weaker, over time.

    Scientists began their search with an ancient recipe for mortar, laid down by Roman engineer Marcus Vitruvius in 30 BCE. It called for a concoction of volcanic ash, lime, and seawater, mixed together with volcanic rocks and spread into wooden moulds that were then immersed in more sea water. History contains many references to the durability of Roman concrete, including this cryptic note written in 79 BCE, describing concrete exposed to seawater as: 'a single stone mass, impregnable to the waves and everyday stronger.'

    What did it mean? To find out, the researchers studied drilled cores of a Roman harbour from Pozzuoli Bay near Naples, Italy. When they analysed it, they found that the seawater had dissolved components of the volcanic ash, allowing new binding minerals to grow. Within a decade, a very rare hydrothermal mineral called aluminium tobermorite (Al-tobermorite) had formed in the concrete. Al-tobermorite, long known to give Roman concrete its strength, can be made in the lab, but it's very difficult to incorporate it in concrete.

    But the researchers found that when seawater percolates through a cement matrix, it reacts with volcanic ash and crystals to form Al-tobermorite and a porous mineral called phillipsite. So will you be seeing stronger piers and breakwaters anytime soon? Because both minerals take centuries to strengthen concrete, modern scientists are still working on recreating a modern version of Roman cement.

    Science Magazine / American Mineralogist    July 03, 2017