Firefly chemistry in less glowing terms
The eerie glow of the firefly has been trumpeted for half a decade as an exceptionally efficient example of bioluminescence - where a chemical reaction inside the insect emits light. The reaction, in which luciferin molecules are oxidised to excited states that relax to the ground state and emit photons, was measured in 1959 to have a maximum quantum yield of 88 per cent; that is, almost all the luciferin molecules that reacted subsequently emitted photons.
Yoriko Ando and colleagues from the University of Tokyo, Japan, have re-evaluated that efficiency with a new photon-flux spectrometer, and say that the chance of photons being emitted from reacted firefly d-luciferin (the active optical isomer) is, at best, only around 41 per cent. That’s still more energy-efficient than other organisms, including bacteria and marine life, but not exceptional.
The researchers, publishing in Nature Photonics (DOI: 10.1038/nphoton.2007.251), also explained that the colour change in a firefly’s glow is determined mainly by the way its green light emission changes with pH levels.
Max Planck goes to Florida
Germany’s Max Planck Society has confirmed it will establish its first institute in the US: a bio-imaging centre at Florida Atlantic University (FAU) in Palm Beach County. The Max Planck Florida Institute will be housed near Scripps Florida, a biomedical research institute which is part of the California-based Scripps Research Institute. Work in three departments (molecular imaging, biosensing and cellular mechanisms) could begin next year; at full strength, the institute is expected to have about 150 researchers from around the world. Florida taxpayers are footing much of the bill. Palm Beach County has already approved $87 million over the next 10 years to support the institute, with the State of Florida expected to provide a comparable amount.
Crystal clear predictions
A team of researchers has correctly predicted from first principles the crystal structures of four organic molecules, in the latest incarnation of a triennial competition organised by the University of Cambridge, UK. Avant-garde Materials Simulation (AMS), of France, were the only team out of 15 entrants who managed to predict the correct packing arrangements of all four compounds, given only their molecular structure and crystallisation conditions. The small molecules were chosen by the Cambridge Crystallographic Data Centre to have a wide range of properties.
No-one had ever before managed to crack the whole challenge, which has been running since 1999. AMS’s success showcases the power of modern computing techniques to solve crystal structures - which define material properties such as solubility, hardness, and colour. But accurate structure prediction would be most useful for pharmaceuticals, and computer programs have not yet reached that level of complexity. The next challenge is scheduled for 2010.
Methane future for oil recovery
An international research team has worked out how microbes in oil reservoirs slowly ferment crude oil into methane gas and heavier deposits. If this natural process can be accelerated, they say - by feeding the microbes the correct nutrients - then extra energy might be more cheaply recovered from heavy-oil fields in the form of clean-burning methane.
As hydrogen is an intermediate in the methane-generating pathway, it is possible that hydrogen might be recovered as well, the researchers suggested. Sequestered carbon dioxide might also be converted into methane by the same process; the methane could be burnt as fuel and the resulting carbon dioxide cycled round the process again.
The team, publishing in Nature (DOI: 10.1038/nature06484), said field tests for accelerated biodegradation in an oil reservoir would likely begin in 2009.
Grants for Europe’s researchers
The European Research Council (ERC) has announced it will provide around
The scheme operates alongside the ERC’s Starting Grant scheme (for young researchers), which has
The ERC, launched in February 2007, is intended to be the EU’s flagship funding program for blue-skies science, and billed as Europe’s answer to the US National Science Foundation (see Chemistry World, January 2007, p44). It is supported by the EU’s 7th framework research program (FP7), but managed by an international team of researchers, rather than EU officials. New calls were also announced for FP7 grants last month.
Germany’s emissions plans
German chancellor Angela Merkel has approved ambitious legislation which aims to cut Germany’s greenhouse gas emissions by 40 per cent by 2020, compared with 1990 levels.The EU-wide commitment is to reach a 20 per cent cut in emissions by 2020.
The package of energy policies, which requires a 2008 commitment of
German environmental groups, however, criticised Merkel’s green image, pointing out that the government planned to build 24 new coal-fired power stations to replace phased-out nuclear plants.
Spanish chemists have strung C60 buckyballs together in a polymer looking rather like a pearl necklace, which both accepts and donates electrons. The monomer unit consists of a buckyball attached to a complementary baseball-mitt-like pincer, which can grip another C60 unit tightly through non-bonding interactions.
The new polymers are up to 300nm in length and maintain their structure even in solution. The team, led by Nazario Mart?n at City University in Madrid, hope the necklace-like strings could be useful in organic solar cells or other devices which manipulate electrons. So far, it has been difficult to find any practical use for buckyballs. The polymers, reported in Angewandte Chemie International Edition (DOI: 10.1002/anie.200703049), are about 5 million times smaller than a real set of pearls.
Chemical analysis of ancient jade jewellery found throughout Southeast Asia has revealed one of the most extensive sea-based trading networks of the prehistoric world.
Researchers at the Australian National University in Canberra used electron probe microscopy to analyse jade lingling-o earings and double-headed animal ear pendants. These ornaments are found across a 3000-kilometre wide region centred on the South China Sea. But 116 of the 144 artefacts studied had silicon, magnesium and iron elemental ratios showing they all came from one jade deposit in eastern Taiwan.
From there, during the early Iron Age (500BC -AD500), the jade was traded in a vast network that may also have helped spread Austronesian languages, said the researchers, publishing in Proceedings of the National Academy of Sciences USA (DOI: 10.1073/pnas.0707304104).
Giant UK medical project secured
The UK government is supporting the creation of a ?500 million Centre for Medical Research and Innovation in central London, to be sited next to the British Library and the Eurostar terminal at St Pancras Station. Up to 1500 researchers are expected to work at the centre, due to open in 2013. It will focus particularly on turning research discoveries into new treatments. The centre’s future was assured after it won a bidding contest for land from the government. It is a collaboration between the Medical Research Council (MRC), the Wellcome Trust, Cancer Research UK and University College London. Scientific planning for the project will be led by Nobel laureate Paul Nurse.
Seeds of doubt
US-based company, Planktos, has announced plans to dump 50-100 tonnes of iron sulfate into a patch of ocean 100km wide at a ’secret location’ before the end of January, in a bid to seed the growth of plankton - and so remove CO2 from the air by photosynthesis.
The trial is only the latest in a series of such tests; but it is also the largest to date, and scientists are increasingly sceptical about the idea. The hope is that new biomass will fall to the bottom of the ocean, dragging CO2 with it. But recent studies warn that CO2 captured in this way might not stay under water for very long.
In November 2007, the London Convention called for more research into ocean fertilisation before any commercial projects get underway. Its scientific advisory board chairman, Chris Vivian, told Chemistry World that Planktos’ approach, while not considered large-scale, was somewhat ’gung-ho’.
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