Category Archives: Science & Technology

Diamonds are Forever? Probably. – David Cliff


The rather tongue-in-cheek nature of the title belies the fact that diamond can be reduced to carbon dioxide if a high enough heat source is applied to it so that it readily oxidises. However, there is a serious side to the stability of diamond under the ‘right’ conditions. Diamond is a metastable allotrope of carbon and is the hardest naturally-occurring substance on earth. It also has the highest thermal conductivity of any bulk material. With a specific gravity of 3.52, this makes it dense relative to the host rock and thus enables relatively simple recovery techniques to be used in the mining industry. Optical dispersion gives diamond its desirable characteristics for the jewellery industry, although the biggest proportion of all production lies in the industrial applications; abrasive tools and cutting applications. 80% of the 130 million carats mined annually are used in industry and 4.5 billion carats are produced synthetically. The highest value diamonds are marked up some six fold at retail from the US$9 billion annual mine production after passing through the cutting, polishing and marketing stages. Continue reading Diamonds are Forever? Probably. – David Cliff


Can plants talk? – Angela Wall

Although plants appear not to communicate by sound, they can communicate with plants and other organisms in many ways. Plants cannot run away, so In order to survive they are able to call for help, eavesdrop on neighbours, defend themselves and neighbours against herbivores and diseases, defend their territory, alert neighbours to drought conditions, recognise siblings and help each other out with nutrient transfer. Continue reading Can plants talk? – Angela Wall


The Special Theory of Relativity, Part 2 – Mass, Energy & Space / Time – Richard Jones

Richard’s presentation on Special Relativity Part 2 began where Part 1 ended, looking at the experience of a person travelling at relativistic speeds. The visual effects are aberration of light from stars around a spacecraft, the Doppler shift and the so-called searchlight effect. The twin paradox of unequal ageing of travellers was briefly mentioned but this is properly in the domain of General Relativity. Continue reading The Special Theory of Relativity, Part 2 – Mass, Energy & Space / Time – Richard Jones


Is there life after industry? – Prof Michael Johnson

Prof Johnson had conducted a fundamental review of natural environmental services at the University of Liverpool in partnership with Merseyside County Council. He had held a lectureship at Liverpool, & had then been offered a chair at Imperial College, London. However, the Rio Tinto Company had endowed a personal chair for him at the University of Liverpool, following which he sometime later moved into the private sector as a consultant to the mining industry.

He had studied the estuaries & coastal waters, & particularly pollution of the Mersey Basin. High levels of toxic metals (Hg & Cu) had been found in the fish in these waters, with peak levels of Hg in ~ 1980 thru 2015. Discharge from local chemical industry was found to be the source of this pollution. There were also toxic organic pollutants (e.g. pesticides & PCBs) found in estuary fish. By comparison, the Dee estuary was much less polluted. Continue reading Is there life after industry? – Prof Michael Johnson


U3A Explores Science at the Ri

A couple of group members attended this interesting event. The presentations were:

  1. Prof. Ian Crawford (Birkbeck College) – “Where are the aliens?”
  2. Michael de Podesta (NPL) – “How do we know anything? And how can we know things better?”
  3. Catie Williams (UCL) – “Wild at heat but captive in gut: Exploring the effects of life in captivity on the gut microbiomes of re-released chimpanzees”