On the Spectrum of Elementary Silicon

On the Spectrum of Elementary Silicon, Crookes, William , Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character (1905-1934), 8/1914, Volume 90, Issue 621, p.512 - 520, (2006)

On the Arc Spectrum of Scandium

On the Arc Spectrum of Scandium, Crookes, William , Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character (1905-1934), 6/1919, Volume 95, Issue 672, p.438 - 439, (2006)

On the Arseniates.

On the Arseniates., Dalton, John , Abstracts of the Papers Printed in the Philosophical Transactions of the Royal Society of London (1800-1843), 1/1837, Volume 4, Issue 1, p.162 - 162, (1837)

On the Constitution of the Atmosphere.

On the Constitution of the Atmosphere., Dalton, John , Abstracts of the Papers Printed in the Philosophical Transactions of the Royal Society of London (1800-1843), 1/1815, Volume 2, Issue 1, p.267 - 268, (1815)

Royal Society Digital Journal Archive Free from 23 Nov to 28 Feb 2010

Royal Society Digital Journal Archive Free from 23 Nov to 28 Feb 2010

The year "2010 is going to be a very special year at the Royal Society. As the worlds oldest science academy, we are looking forward to celebrating our 350th anniversary and to mark this special occasion we are making our digital archive containing more than 65,000 articles free to access.

The Royal Society Digital Journal Archive is easily the most comprehensive archive in science and contains some of the most significant scientific papers ever published. Covering almost 350 years of scientific research across the disciplines it is a priceless academic resource, free and exclusive to our journal package subscribers."

The complete archive is available online at http://royalsocietypublishing.org/journals and is free as part of one of the Royal Society's journal subscription packages.



GoElemental! screen shot from http://www.goelemental.co.uk/index.html


Silicones contaminate fuel in Southern England

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.

The silicones were probably introduced inadvertantly at storage rather than at the refinery stage.

This is going to get expensive for someone as it sounds as though thousands of cars have been affected.

Polonium: did it kill Alexander Litvinenko?

Polonium metal structurePolonium metal structureIt 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.

Polonium dioxidePolonium dioxidePolonium dissolves in acids to form pink hydrated Po(II), presumably as[Po(OH2)6]2+. This seems to oxidize to yellow Po(IV) species perhaps as a consequence of oxidizing agents produced through the α-particle induced decay of water. The polonium(II) oxide PoO is known but this oxidizes easily to the Po(IV) oxide PoO2.

Polonium dichloridePolonium dichlorideThe Po(II) halides PoX2 (X = Cl, Br, I) are known (the chloride and bromide are particularly well characterised) while all the Po(IV) halides PoX4 (X = F, Cl, Br, I) are known.

There are few crystallographically characterised polonium compounds largely because not many researchers work with polonium and the difficulties associated with characterising such radioactive compounds. The 14-electron polonium(IV) anion [PoI6]2– is strictly octahedral meaning the lone pair is sterochemically inactive.

A little more cash for English University Science

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.

The additional funding for chemistry, physics and the other subjects mentioned is said to increase the HEFCE teaching grant for these subjects by approximately 20 per cent or by one thousand pounds per student.

  1. Terms and conditions will be attached to the funding, which will include a requirement that institutions maintain teaching capacity in the subjects concerned. The money will be allocated by formula to reflect the scale of teaching activity at each institution in the subjects concerned. The details of the allocation method will be considered by the HEFCE Board in January.
  2. Full details about the range and scope of the £160 million programme of work to support strategically important and vulnerable subjects is available in the HEFCE October 2006 update to the Secretary of State

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Copyright 1993-2011 Mark Winter [The University of Sheffield and WebElements Ltd, UK]. All rights reserved.