Here in the UK, Channel 4 just screened an interesting documentary: The Great Global Warming Swindle. Good viewing and challenges what seems to have become the accepted view that global warming is caused by man-made CO₂ emissions.

For the last few days there have been many reports of damage to car oxygen sensors in England's south east. This seems to have been cause by faulty fuel supplied by some supermarker chains, including Tesco and Morrison's. Initial reports suggested the fuel was up to standard but one wonders if this is a consequence of not applying the correct tests. Expecially now that reports are emerging (for instance from The BBC) that indeed there is a contamination arising from silcon, probably from silcone contaminants. Silicones are used in diesel but damage high-tech petrol engines.

Polonium has no biological role and any sample used to kill the former KGB spy must have come from either a research laboratory or nuclear facility. It is found in uranium ores but at miniscule levels 0.00000001%. So small that the Curie's were awarded the Nobel prize for their superhuman effort to extract it. Could a terrorist smuggle Polonium into this country or is there a human leak at a UK Defence Establishment? Gramme quantities of polonium-210 are synthesized from bismuth in nuclear reactors. Carrying quantities of polonium is difficult because of the high temperature from radioactive decay [500oC] and the emission of deadly alpha particles. These radioactive particles are most dangerous when ingested. They pick up electrons from cells in the body and escape as helium gas. Polonium-210 has a relatively short half life [138 days] so the 'evidence' diminishes constantly with time. Also Polonium is fairly volatile and will evaporate if not kept in a sealed container. Polonium is one of the deadliest known substances and is believed to be a trillion more times toxic than HCN weight for weight.

It is suggested that poisoning by polonium-210 may have caused the death of Alexander Litvinenko, said to be a former Russian spy, in November 2006. Following his death at the end of November 2006, traces of polonium were found at several places he had visited before becoming ill. Before his death it was thought that thallium, or even radiothallium, might have been the cause of his illness. At the time of writing it is not clear who killed him, but not surprisingly the Russians deny it. Polonium-210 decays through the emission of α-particles and these emissions are noramlly easy to stop, but they are very dangerous if the polonium is inside the body.

Polonium is radioactive and present only in extremely low abundances in the environment. It is quite metallic in nature despite its location beneath oxygen in the periodic table. It is made in very small quantities through a nuclear reaction of bismuth. Neutron irradiation of ²⁰⁹bismuth (atomic number 83) gives ²¹⁰polonium (atomic number 84).

²⁰⁹Bi + ¹n → ²¹⁰Po + e^-

Polonium-210, ²¹⁰Po, transmutes into the lead isotope ²⁰⁶Pb by the emission of an α-particle. The half life for this process is just over 138 days meaning that after 138 days one-half of the original ²¹⁰Po has disappeared and after 2 times 138 days ³/₄ has gone.

²¹⁰₈₄Po → ²⁰⁶₈₂Pb + ⁴₂He

The short half life of polonium-210 and the heat generated with the above radioactive decay means that polonium metal generates considerable heat (141 W), meaning that the metal and its compounds self-heat. This is a useful property and polonium can be used as a small heat source (if expensive!). It can be used in space satellites for this purpose and is especially desirable as there are no moving parts. It was also used in the lunar rovers to keep internal parts warm during the frigid lunar nights.

Polonium metal is unique in that it is the only element whose structure (known as the α-form) is a simple cubic array of atoms in which each atom is surrounded by six other polonium atoms. On gentle warming to 36°C, this converts into a second form known as the β-form.

HEFCE to provide an additional £75 million to support very high cost and vulnerable science subjects

The Higher Education Funding Council for England is to provide £75 million in additional funding to support very high cost science subjects, which are strategically important to the UK economy and society but vulnerable because of relatively low student demand.

The funding over three years from 2007-08 will support chemistry; physics; chemical engineering; and mineral, metallurgy and materials engineering - to help maintain provision in these subjects in universities and colleges while demand from students grows.

Good to see that the complete works of Charles Darwin, one of the greatest scientists, are being published online by Cambridge University. Darwin Online features many newly transcribed or never-before-published manuscripts and is worth anyone's time to browse around for a while. The great English naturalist Charles Darwin (1809-1882) revolutionized our understanding of life on earth.

The Institute of Physics announced its regret at the decision of the University of Reading to close its Physics Department. The Institute of Physics science director, Peter Main said, on learning of the impending closure of the 33-strong department, “University vice-chancellors are operating in an environment that is controlled by the choices of seventeen-year old students. Funding follows student numbers and so the future of Britain’s science base rests on the university choices of sixth-formers. In addition, laboratory-based subjects are not adequately funded. This is a clear example of market failure. The government has to realise that its aspirations for science, set out in the chancellor’s “Next steps” programme following the March budget, will not happen unless they look again at how university departments are funded; the current model disadvantages laboratory-based subjects, especially physics”.