University of Malta scientists, who have developed a way of reducing the impact of thermal expansion, are attracting the attention of the international scientific press, the university said yesterday. Their groundbreaking work was published this week in the Proceedings of the Royal Society A by an academic from the university’s Faculty of Science and his research team and is making headlines internationally.
It is being reported as breaking news by New Scientist.com, the website of New Scientist, which is cited as the world’s number one science and technology news service. On this website, a global network of specialist correspondents promote important scientific discoveries that are likely to have a significant impact on society.
The team of University of Malta scientists, led by Dr Joseph N. Grima and colleagues Pierre-Sandre Farrugia, Ruben Gatt and Victor Zammit, have developed a way of designing structures, of any size, that shrink when heated (negative thermal expansion). Their work, funded by the Malta Council for Science and Technology (MCST) and CHISMACOMB (an EU FP6 project), can be extremely useful in reducing the impact of thermal expansion on anything from bridges to microscopic systems.
“The University of Malta is gradually building an infrastructure to conduct world-class research in niche areas of engineering, science and medicine. Though we do not have a long-standing tradition of institutional research, and despite the very modest funds to sustain such endeavours, our up-and-coming researchers have shown, time and again, through their publications, that they can put us on the international map of scientific and technological innovation,” said University of Malta rector Juanito Camilleri.
The project was partly funded by the National Research Technological Development and Innovation (RTDI) Programme launched in 2004 by the MCST. The National RTDI Programme is aimed at stimulating and building a culture for sustained scientific research and innovative activity by providing financial support for scientific research, ranging from basic and applied research to near-to-market innovation.
The University of Malta team studied triangles with at least one side made from a different material to the others, connected by rotating joints. If the diverse materials change volume in response to temperature in a different way, the triangles may actually shrink in one direction when heated. They derived equations that describe the behaviour of their triangle-framework system and these are essential to predict the response to temperature of their structure, which can be constructed on any scale. In other words, their mathematical model makes it possible to choose exactly how such a structure behaves. For example, they show that if one side of a triangle is more responsive to heating, it will stretch the other two wider, drawing the point opposite closer, thus resulting in a reduction in the height of the triangle.
Dr Grima and his colleagues think lattices of such triangles could have all kinds of applications. “We have shown that it is possible to easily design systems that exhibit a tailor-made response to temperature,” says Dr Grima. “These systems can be constructed very cheaply and can be as big as a bridge or on a microscopic scale.”
By virtue of its construction, this structure should be able to bear loads without problems, he adds. The team is starting to experiment with real frameworks to see how they perform. Dr Grima’s team of scientists is also interested in more complex materials. “By incorporating such a rigid framework into another softer material – like rubber – you could create a ‘solid’ with these anomalous thermal properties,” he says.
This is not the first time that academics from the Faculty of Science are reporting such groundbreaking news in the proceedings of the Royal Society. In fact, more than a century ago Professor Sir Temi Zammit, the first Dean of the Faculty of Science, published in Proc. Roy. Soc. B. his famous note A Preliminary Note on the Susceptibility of Goats to Malta Fever.
Further information is available from: http://home. um.edu. mt/auxetic/nte.html