In Somerset, England, a unique experiment is going on. A few cars, including 10 police cars using ethanol, a fuel made of fermented Brazilian sugarcane.

The supply chain now being limited to just five pumps, will be upgraded in about three years fuelling some 300 cars or so that run on this fuel made at a special plant using England’s surplus wheat.

There is a sort of dis-coordination in Britain, on bio-fuels, it seems. At Gleneagles summit of G8 leaders, all the VIP cars were flexi-fuelled, that can use bio and conventional fuels. But the green agenda announced with great fanfare seems to have lost.

In Britain, ethanol bio-fuel costs slightly less than regular petrol and the flexi-fuel vehicles, say Ford Focus cars, are priced comparably to regular cars. It looks promising as fuel of future world wide particularly when global warming trend is increasingly becoming certain. Many swear that these could certainly help curtail Britain’s carbon emissions.

The House of Commons Environment, Food And Rural Affairs select committee advocated that this experiment need to be replicated in many more councils, businesses and government departments. But what baffles one is that there are five different departments that look after the bio-fuel development. The policies outlined by the committee are felt as too vague and without long term vision, to rope serious private players into business.

Clearly, the research across the world including the US is indicating that the global warming rate is alarming and bringing several other hitherto unexpected factors into the list of variables affecting the warming rate. For example, the sheetice melting and detachment from areas like Green land and the release of methane from thawing permafrost and heating oceans could actually send the rate of warming spiraling and many fear that a point of no-return is fast approaching Planet Earth.

In this grim situation, every opportunity that cuts or helps cut the green house gas emissions need to be embraced. For example, Sweden, perhaps the Europe’s greenest country, encourages bio-fuel by exempting cars using it from congestion tax and parking fees.

So is it the ultimate fix to all ills? Certainly, no! As much it is a great opportunity as it is a danger. If fuel crop were given intensives and bio-fuels are taken as the fix for all energy shortages, the farmers may be tempted to switch to fuel crops from food crops. The already stressed crop areas would further be threatened. With less availability of farm land, farmers will switch to clear forests and buffer zones between forests and crop lands. This apart, the bird and other animal species that depend on these lands would face threat. The ecological implications were too intricate to understand right now.

So, success lies in actively encouraging bio-fuel, as a renewable energy and, making it good part of a larger set of alternative fuels. It is not bad news at all. The fossil fuels burn carbon fixed from atmosphere into plants over millions of years adding to atmospheric CO2 but the bio-fuel crops fix carbon from atmosphere and recycle them into alcohol through fermentation. There shall be no net increase in atmospheric carbon.

Here the economics slip in. the bio-ethanol is priced at about the same as the regular petrol but the ethanol gives only two thirds of the mileage given by petrol. So, there is no effective incentive to drivers who switched to bio-fuel. Mere gestures of lowering duty on ethanol and levying penalty on oil companies that stick to pnly petrol and diesel will not do much. There needs to be some pragmatic approach.

One up thing here to this debate is it brought all the necessary points of view to the fore. Let us expect Britain and the countries, notably US under the listless Bush administration wakes up to the challenge and do some sensible thing to the only known habitable planet of our near universe.

The News:

The precious metals of gold and silver got a more precious role to play - in the field of water purification. Two scientists from the Indian Institute of Technology, Madras, T. Pradeep and A. Sreekumaran Nair, have patented technology to use gold and silver nano-particles to filter dreaded pesticides like endosulfan, malathion and chlorpyrifos from wa¬ter.

What did they do?

The process makes use of the nano-technology. Nano particles are very small in size, in the order of millionth fraction of a millimeter, to be precise. The technology relies on the ability of the nano-particles of gold and silver to bind with the residual pesticide molecules from flowing water through adsorption (not absorption! Adsorption is condensation /formation of a layer of liquid or gas on the surface of a solid (grain)).

Eureka Forbes, which makes the Aquaguard range of multi-step water purifiers in India, have acquired a license to use this new technology. It is all set to roll out products featuring this tech¬nology soon, says P.J. Reddy, Director of Aquamall Water Solutions Lim¬ited, a subsidiary of Eureka Forbes. Initially they may make use of this technology in their high-end products, reported The Hindu.

Amidst the raging controversy over, profit happy Cola Multi-national corporations allegedly implementing different quality commitments in India as against the American, European and other advanced countries, such a technology is most welcome in India. Before Colas, the same Centre for Science and Environment (CSE) also exposed the double standrds of these Cola majors and other bottled water manufacturers on the pesticide content well above prescribed levels.

Though, Indian government have, controversially gave a clean chit, no one believed them. The track record of the government and these cola firms in India is all too well known. In such a scenario, the scientists naturally hope that the technology would address the growing concern over access to safe drinking water. Obviously, it is useful for other countries as well.

Dr. Pradeep and his IIT colleague Birgit R. Burgi, co-authored a paper tiltled “Societal implications of nano0s¬cience and nano -technology in de¬veloping countries.” This article published in the Cur¬rent Science journal, notes that “Water purification systems equipped with nano-materials and using new kinds of membrane technologies with variable pore

sizes as filters could provide people in any area with safe drinking water,” reports The Hindu.

How it works?

During 2003 and 2004, Dr. Pradeep and his team of scientists at IIT, Madras have discovered that gold parti¬cles of diameter 10 to 20 nano-¬metres and silver particles of diameter 60 to 80 nano-metres had the tendency to adsorb pesticides, effectively filtering the flowing water of these impuarities. The nano-parti¬cle solutions changed colour inn the presence of re¬sidual pesticides in water.

However, the regulations of Bureau of Indian Standards (BIS) stipulates acceptable level of residual pesticide as 0.5 ppb (parts per billion) but the scientists could not measure with that much precision for lack of precise instrumentation.

Current Scenario:

So, is it end of the euphoria? No, certainly not! The Aqua Diagnostic Labs of Eureka Forbes near Bangalore is internationally-certified and the tests conducted there on gas chromatography equipment with electron capture detector actually showed that the nano-par¬ticles adsorbed the pesticide molecules. The presence of residual pesticides also found to be below the prescribed levels.

The good scientists, while suggesting to better use the technology on a large scale purification system like a community treatment plant, than in home water purifiers, have offered even to waive the royalty, if any village panchayat (local self governing body of a village) approaches for a communi¬ty water purifier.

For the past several years, biologists have watched proteins and other molecules travel in and around cells and tissues due to the invention of tiny little fragments of matter known as quantum dots. A blast of light makes these fragments glow different colors depending on their size, allowing the masterpiece of life to become visible and coded with color. The current quantum dots available, however, contain poisonous Cadmium and hence are not suitable from the point of view of biology. But now, researchers at Clemson University (SC) have come up with a revolution kind of in chemistry and have made quantum dots from carbon which is a new step in quantum dot-tery (J. Am. Chem. Soc. 2006, 128, 7756–7757).

Seen on the large scale, we can easily find some materials that are fluorescent which means that they give off light when a different colored light is put on them. For example, the light from a fluorescent light bulb is originally ultraviolet which is not apt for humans. But, after it hits the phosphors that coat the inside of the glass of the bulb, the UV is absorbed and the light emitted thereafter is what we can see and use.

When the above absorption is taking place, some electrons, which are in a ground state, move into a higher energy excited state. This leads to an empty spot called a hole where the electrons had been. The electron and the hole can both move from place to place, but as soon as they face each other again, the electron comes back to its original ground state, fills the hole and the excess energy is emitted in the form of light.

The color of the light so emitted is respective to the energy difference between the electron's excited state and its ground state which in normal materials are properties of the materials themselves. So, if a material fluoresce red it will always glow red and not any other color. To change the color of the light emitted, use of a different fluorescent material is required.

However, things are not the same at the nanoscale. Quantum dots are so small that the size of the dot determines the energy levels that electrons can obtain. Thus, the size and not the material control what colors are produced.

A mention of quantum dots brings to mind those made from cadmium selenide (CdSe) which have been researched extensively to obtain quantum fluoresce.

The quantum dots made from carbon have a different mechanism than their CdSe counterparts, as explained by Sun Ya Ping, one of the researchers at Clemson University. This signifies that in the case of CdSe, the semi-conducting nature of the material decides how light is made, but for carbon something else does.

To make carbon quantum dots, laser ablation of graphite power and cement was used to make carbon particles which made the particles form aggregations (and hence no fluoresce). The particles were than coated with simple organic molecules which passivated the surface which led to bright luminescence.

The simple organic molecules used, such as diamine-terminated oligomeric poly(ethylene glycol) and poly(propionylethylene-imine-co-ethyleneimine), did not have any luminescent activity alone but when put along with the carbon dots, the carbon dots became luminescent.

Probably, the best thing of the carbon quantum dots is that they do no blink. This means that unlike their other counterparts, they do not turn on and off at intervals which is a major problem. This discovery could be used in medicine where cadmium-based quantum dots are unsuitable. Other uses include LEDs, lasers, and lighting.