Extinction alert

The latest environmental bad news is that over the past decade we have seen significantly fewer cuckoos and other birds generally thought to be 'common' here. Our organisation is currently working to help monitor and address some of the factors that have resulted in a catastrophic decline in the number of vultures in Africa and India. Evidence suggests that the use of agricultural pesticides and pharmaceuticals is having a significant impact on their numbers. In Africa, vultures and other wildlife are having to compete directly with people for increasingly scarce habitat and food resources.

There are several messages that we can take from the plight of the vultures, and now from the cuckoos. One is that all species, no matter how abundant they appear to be, are susceptible to extinction. Keeping common species common is really trying to prevent their extinction, proactively. 

We agree with Prince Charles' belief that we have less than 10 years to halt what will otherwise be an irreversible degradation of wildlife habitat and biodiversity. The root cause of the problem is a burgeoning human population which is rapidly squeezing out the existence of an irreplaceable number of species. 

One of the most pressing needs is for governments to put the inexorable rise in human population and the oppression of people at the top of the political agenda. We are proposing as a starting point for discussion, a small reduction in birth rate to result in a managed global population decline of 0.05-0.1 per cent per year. 

Additionally, governments must put biodiversity and conservation issues on an equal footing with the need to feed, house and provide resources for people. Our quality of life is largely dependent upon maintaining the integrity of our ecosystems and ensuring that biodiversity thrives. We should strive for all people to have a good quality of life and must not underestimate the importance of a healthy environment. 

The consequences of failure to act now will be a rapid and dramatic reduction in quality of life, including drought, famine, disease and war, followed shortly thereafter by a catastrophic and unmanaged human population crash. 
S Lancaster CSci CChem FRSC and N Richards, Foundation for Analytical Science & Technology in Africa, Hessle, UK 
A Gachanja CSci CChem MRSC
Jomo Kenyatta University of Agriculture & Technology, Nairobi, Kenya 

Cavalier chemist

David Jones (Chemistry World, June 2009, p84) is way off beam to believe that DuPont chemist Roy J Plunkett acquired the first sample of PTFE ever seen by cavalierly cutting open a seemingly empty, yet above-tare TFE storage cylinder. In fact, as Roy described years ago in High performance polymers: their origin and development  (eds. R B Seymour and G S Kirshenbaum, Elsevier: New York, 1986), the TFE cylinder's valve was checked for a blockage then removed and the cylinder turned upside down. Out came a whitish powder - subsequently shown to be PTFE - and further material was recovered later by cutting open the cylinder. Incidentally, Roy was assisted by a technician, Jack Rebok, and their discovery was made in 1938 (April 6) not 1937 as stated by Jones. 

Roy Plunkett (right) and Jack Rebok (left) re-enacting their 1938 discovery of Teflon at DuPont laboratories © DUPONT

The two pages from Roy Plunkett's lab notebook which record the first sightings of PTFE were reproduced in the Moissan Centennial issue of the Journal of Fluorine Chemistry  (1986, 33, 102) together with a copy of the famous re-enactment photograph (above) showing Plunkett and Rebok, in the presence of Robert McHarness, recovering PTFE from two halves of a cylinder once used to store TFE; perhaps Jones got the impression that Plunkett was saw-happy by viewing that photograph (or a copy elsewhere).  

I wrote to Plunkett in 1985 asking whether or not the cylinder at centre foreground in the photograph was the original one. He replied: 'I had stored tetrafluoroethylene in several dozen cylinders and polymerisation occurred in many of them. The picture [sic] re-enacting the discovery shows a cylinder slightly different from the one in which the polymer was originally discovered.' 
R E Banks CChem FRSC 
University of Manchester, UK 

Public inventions

I read with interest the Comment by Lord Drayson on the use of results arising from publicly funded research in the UK (Chemistry World, June 2009, p39). 

I think he should have mentioned the work of the former National Research Development Corporation in this field. NRDC was set up soon after the second world war with the sole object of exploiting such inventions in the public interest. In the period before it was closed down by Margaret Thatcher's government, it supported work to commercialise inventions including new antibiotics, MRI, new materials (carbon fibres, new alloys etc) and many others. 

NRDC did all of this at no cost to the tax-payer by using the proceeds of licensing inventions, where possible to UK companies, but otherwise to the most appropriate international companies. 

It also funded small-scale seedcorn projects to demonstrate the utility of new ideas in UK academic institutions. 

NRDC was highly effective in providing patent protection for public sector inventions and in licensing them.  

The net revenue from this was shared with the inventing institution which usually passed on most of this to the individual inventors. 

The Development of Inventions act was eventually abandoned by the Thatcher government in the 1980s but I believe it is a pattern for handling publicly funded research results in the future. 
J G Walker 
Chelmsford, UK 

Glass blowing

I would just like to thank you and encourage you to keep up the Classic kit  column. As a glassblower for many years, now employed at Texas Tech, it is refreshing to see the information that many in my field would love to have. The articles are extremely important to explain the use of glassware - who invented it and why they invented it - to both chemists and glassblowers, who make the product but never know what it is used for. 
D Hodgkins 
Texas Tech University, US 

Microwave pioneer

It was most enjoyable to read about the phenomenal growth of microwave-assisted chemical synthesis (Chemistry World, October 2008, p40). The steps leading up to the first publication in this field might be of interest to readers. 

In the early 1980s, the mining and smelting industry had come under increasing pressure on two main fronts: economic and environmental. This made efficient management more dependent on reliable chemical analysis. During this same period, analytical chemistry instrumentation was becoming more sophisticated. However, many of these advanced instruments required the sample to be in solution form prior to analysis. But sample dissolution techniques had hardly changed for a century or more. Thus sample preparation became the slow step in the analytical process.  

At the time, I was working at Laurentian University in Sudbury, Ontario, Canada, a world-class centre of the mining and smelting industry. In collaboration with John Bozic, of INCO, a project to develop the microwave-assisted pressure dissolution of mineral and metallurgical samples began. The major hurdle at this stage was finding suitable reaction vessels that could withstand high temperatures and pressures and strongly acidic conditions. We tried commercially available polycarbonate and Teflon bottles and had vessels specially carved out of solid Teflon blocks - all to no avail. In fact we had a few explosions and some spectacular instances of vessel deformation.  

But then we found that Teflon-PFA tubing made by the Savillex Corporation, US, was ideal, if short sections were fitted with end caps. The company made some vessels for us. These became the vessels of choice and this breakthrough led to the first proven published method in this field.¹ 

Since we now had the (domestic) microwave ovens and suitable vessels, I enlisted the aid of two LU organic chemists, Richard Gedye and Ken Westaway, to investigate some organic synthesis reactions. We put some undergraduate students to work during the summer and quickly found that the technique was readily adaptable to organic synthesis, leading to some remarkable decreases in reaction times. 

Since our first publication,² the field has grown rapidly. It is encouraging to see what can be achieved from a small university with minimal funding. As one of the pioneers, I find the extent to which microwave-assisted sample preparation and chemical synthesis have grown since 1985 to be most gratifying. 
F E Smith CChem FRSC  
Weill Cornell Medical College, Qatar 

References

1 F E Smith et al, Anal. Chim. Acta, 1985, 177, 243 
2 R Gedye et al, Tetrahedron Lett., 1986, 27, 279  

Chemical inflation

I write in the hope that some of your readers can answer a query about inflation in the cost of laboratory chemicals. The 1961 edition of Fieser & Fieser, Advanced Organic Chemistry, says that tetranitromethane is costly. It gives the price as $4/10g. The current price(Aldrich) is about 60 times that. Am I right in thinking that this degree of inflation is high in comparison with other things? If so, why? 
E J Behrman MRSC 
Ohio State University, US 

Classic kit to Micro Chip

I didn't realise how much I owed to Wolfgang Gaede until I read Andrea Sella's piece on Gaede's diffusion pump in the fascinating Classic kit  series. 

I worked on a massive metalliser employing, if I recall correctly, 18 pumps of which four were oil diffusion, with the aim to vacuum-deposit aluminium on paper. This was installed in a factory of E S & A Robinson (later Dickinson-Robinson) in Bristol. The pumps were unable to cope with the water vapour without pre-drying the paper until it became brittle.  

Not long afterwards, the factory closed and is now Don Cameron's balloon factory - quite a change of use. The problem was solved in later installations elsewhere, I understand, by inclusion of cryogenic vapour traps in the necessary backing pump sequence. Metallised paper and film is now a familiar sight in supermarkets. 

Two changes of employer later, I followed a suggestion to examine the microwaveable pizzas which had appeared in the US during the 1980s. These were on a curious grey film lamination; this turned out to be an aluminium deposit so thin it acquired a resistance which allowed it to heat up if of roughly similar dimensions to radiation in the domestic microwave oven - 12.5cm at 2.4GHz.  

A leap of imagination led to my successfully applying it to french fries in response to a request by McCain Foods. Steam outgassing from the product is partially removed by convection. When some patent problems were overcome, the Micro Chip - love it or hate it - was born, and has been sold in almost its original form for over 20 years.  

Part of my intention was to enable consumers to eliminate chip pan fires, which can have dire results. So, thank you Wolfgang Gaede, Andrea Sella, and Oscar Seiferth - considered the discoverer of the microwave 'susceptor' used in those pizzas. 
P J Fowler MRSC 
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