SCIENCE TRIBUNE | Thursday, September 20, 2001, Chandigarh, India |
Planet
Earth’s web of life is in danger New
light shed on electron waves
SCIENCE
QUIZ |
Planet
Earth’s web of life is in danger The world today is facing two serious threats; both man-made. One is due to high emission of carbon dioxide leading to global warming. The other is depletion of Ozone layer due to excessive use of chlorofluorocarbons (CFCs) and bromofluorocarbons (Halons). The range of these chemicals is often described as ‘’miracle’’ substances. The use of these chemicals is widespread in the industry engaged in refrigeration and air-conditioning, foam, aerosol (perfumes, shaving foams, insecticides, pharmaceutical, paints, glues etc), solvents (electronic and precision cleaning, coatings etc.) and fire-extinguishing. Warning signals rung for global cooperation to control, if not combat, the two major threats. If allowed to go on unchecked, the two could affect adversely, plant and animal life, thereby, disturbing the very web of life on our planet—the Mother Earth. ‘’The Montreal Protocol—India’s success story’’, a sleek 18-page booklet, says it all. The world was first alerted on the global environmental problem that could have catastrophic consequences by three researches, Paul Crutzen (the Netherlands), Maio Molina (a Mexican-born American) and F. Sherwood Rowland (America) through their article in Nature in 1974, wherein, they had talked of harmful effects of CFC gases on the ozone layer. Their report fuelled global concern and action leading to Vienna Convention, Montreal Protocol and a host of other worldwide steps and agreements, including setting up of a Multilateral Fund, primarily to help the developing countries technically and financially in reducing the use of CFCs and other chemicals replacing them with safer alternatives. All three scientists were awarded 1995 Nobel chemistry prize for their work on ozone layer. The Royal Swedish Academy declared their works as one that has contributed to man’s ‘’salvation’’ from a catastrophy. Incidentally, only one other Nobel prize has ever been awarded in the field of atmospheric research. It was to Sir Edward Victor Appleton in 1947. The story of CFCs, dates back to 1920s when the first of such chemicals were invented in the USA, initially as coolant for refrigeration. The UN stepped-in in 1975, after the Nature report, stirring up the scientific community, worldwide, seeking global cooperation. Though the dangers from the use of CFCs etc. persisted since the industrial age, the real work started only in the past 25 years or so. A word about ozone layer so that as a common man, ozone-friendly consumer, home-owner, farmer, refrigeration servicing engineer or technician, office-worker or industry owner, teacher, community organiser, citizen or saviour of the sky, you too can play a part in protecting the earth by strengthening the ozone layer, up above. Use articles marked ‘’ozone friendly’’ or ‘’CFC-free’’. All life exists within a thin film of air, water and soil about 15 km deep.This shell of life, the biosphere, is divided into three layers, atmosphere (air), hydrosphere (water), and lithosphere (rock and soil). The first is a mixture of gases and particles surrounding our planet. It looks like a seam of dark, blue light on a curved horizon when seen from the space. This atmosphere extends up to a few hundred km above the earth. It is in the shape of rings or layers 90 per cent of these being in the first two regions within 50 km; the troposphere and the stratosphere; the latter extending another 50 km beyond the troposphere. Ozone is a tri-atomic form of oxygen with three atoms instead of the normal two. It forms naturally in the upper levels of the earth’s atmosphere by high-energy ultraviolet (UV) radiation from the sun. It is this ozone that acts as the ‘’sun-screen’’ for the planet protecting it from the harmful dangers of UV radiation, just one form of energy. The other is electromagnetic spectrum. UV is of three types of which B and C are more harmful. The scientists observed that with more and more CFCS getting concentrated in the upper atmosphere, a ‘’hole’’ was being formed in the ozone layer that could spell disaster on the earth, if left unrepaired. That ‘’hole’’ was referred to as ‘’Antarctic ozone hole’’. The scientists from atmospheric records found evidence of seasonal declines in global ozone levels. Increased penetration of solar UV-B radiation is likely to have a profound impact on human health with potential risks of eye diseases, skin cancer and infectious diseases. It also affects terrestrial plants. That would entail evolving plant varieties that are more resistant to UV-B radiation. This could change the bio-diversity in different eco-systems. Since 30 per cent of the world’s animal protein for human consumption comes from the sea alone, it is feared if ozone layer is left un-repaired and unprotected it could mean adverse impact on the productivity of aquatic systems. It is in this backdrop that the United Nations Environment Programme, Division of Technology, Industry and Economics (UNEP-IE) is devoting time to educate the people all over the world creating an awareness and devising information kits, producing audio-video documentaries besides literature and organising training programmes, workshops and seminars for the countries in the process of undoing the damages. Two Indian officials, Rajendra M. Shende and Atul Bagai, look after these aspects of the OzonAction Programme while monitoring the global progress of the actions initiated by the UN agency. For India, the Executive Committee of the Multilateral Fund has approved $ 82 million for the phased reduction and cessation of the entire CFC production. A schedule has been drawn up to implement this as also limits fixed on total CFC production to be done in the country. The status report lists the measures adopted by India as part of the global effort on OzonAction recording the legal steps taken in this regard. A total of 275 projects in the consumption sector have been approved and funded by the Multilateral Fund. Of these 225 are ODS (ozone depletion substances) phaseout investment projects and 50 are support activities. The Centre has also granted full exemption from payment of Customs and Excise duties on capital goods required for ODS phase-out projects funded by the Multilateral Fund. India also has in place the ODS (Regulation and Control) Rules, 2000. In seven sectors, a total of 276 projects have been approved (as on July 31, 2000) with a grant of $ 93,452,852 for phasing out ODS to the tune of 8619.89 tonnes. Those engaged in the OzonAction
Programme worldwide, are aware of the challenges ahead and conscious
not to allow slowdown on the initiatives taken or proposed. |
New light shed on electron waves Scientists have said they were closer to understanding how electron waves moved along nanotubes, tiny cylindrical structures which may one day form the basis of smaller and faster computer chips. Some 50,000 times thinner than the diameter of a human hair, nanotubes are being touted as the future of the Information Age, replacing wires and silicon appliances. Some companies are boasting that they have already built the first array of transistors from the microscopic structures, but researchers said little is known about what goes on inside them. New light has been shed on the minuscule conductors by a team of scientists using a scanning tunneling microscope (STM) to map the undulations of electron waves. "One problem has been that molecular-scale systems such as nanotubes are very difficult to look at even if you can make them," said Serge Lemay of the Delft University of Technology in the Netherlands and co-author of research in the journal Nature. "This kind of experiment gives greater detail on the electronic properties and how the electrons move around in the system," he said in an interview. The STM contains a fine metal tip which feels for "bumps" and "grooves" in the electronic structure at the atomic scale. The apparatus also provides final confirmation of what theorists had predicted — that electrons in metallic nanotubes moved along two different electron "bands" that can interfere with each other. Lemay said his findings were only a small step towards understanding the properties of nanotubes and whether they could one day replace silicon in microelectronic devices. "This work itself is quite a few steps removed from industrial applications," he said. "Research in molecular electronics as a whole could open up the way for doing the chemistry in a beaker and building a circuit that way. "Before we can beat silicon electronics, we must find new ways of making molecular circuits. The new bag of tricks with molecular systems is quantum mechanics." He said the next stage of research with the STM was to look at circuits built from a number of nanotubes as opposed to single structures. "We can start manipulating these electrons to make them interfere with each other and make a circuit. We are still at the beginning of making such a device," he said.
In an accompanying article on the
research, U.S.-based scientists David and Ilana Goldhaber-Gordon wrote
in Nature that advances in nanotechnology, including the prospect of
being able to make defect-free tubes, were an exciting development. Reuters |
Mattress foam with memory Revolutionary heat-sensitive material originally developed for the space programme turns any mattress into a comfortable customised sleep surface. Just because you are asleep, you shouldn’t assume that you are getting the proper amount of rest. Tossing and turning in bed can diminish the value of your sleep. What’s more, most mattresses fail to support your spine properly, which can result in increased pressure on certain parts of your body. Now, one of the world’s leading manufacturers of foam products has developed a revolutionary new material that can actually change the way you sleep. The material is visco-elastic foam, and it is the key to the Memory Foam Mattress topper. Originally developed by NASA to increase the comfort of astronauts during flight, visco-elastic foam represents a quantum leap in bedding technology. The open-celled construction of Memory Foam creates a mattress with a memory. It automatically senses your body weight and temperature, and then it responds by moulding to your body’s exact shape and position. This distributes your weight and reduces stress on your body’s pressure points: the shoulders, hips and legs. This can revitalise your old mattress and make sleeping comfortable again. Now, thanks to improved manufacturing techniques, this revolutionary material is more affordable than ever. Affordable and comfortable. The Memory Foam Mattress Toppers can turn your existing mattress into an ideal sleep surface. The visco-elastic foam is 2 inches thick, which is the ideal thickness for providing comfort and retaining shape over time. When you lie down on this amazing material, the heat-and pressure-sensitive foam reacts to your body’s weight and temperature, so that it moulds to your exact body shape. This means that whether you sleep on your back, stomach or side, your weight is evenly distributed and your spine remains in a neutral position. Other surfaces support your body at the shoulders, hips and legs only. This causes your spine to sag in other areas, which can often result in discomfort, and even back pain. This product not only helps you avoid back pain, it can help reduce tossing and turning. By molding to your body’s shape, the Memory Foam Mattress Toppers can help you sleep more soundly and restfully. You’ll wake up rested, relaxed and ready to take on the day. Anyone who suffers from insomnia, back pain... even arthritis can benefit from this new technology. New ultrasound system Researchers have developed a modular ultrasound diagnosis platform which can serve to evaluate various kinds of examinations as against separate piece of equipment for each different type of examination which was needed earlier. Ultrasound has gained widespread use today in prenatal examinations, physiological testing of internal organs and investigations of tumors and blood circulation. Although the procedures involved are relatively uncomplicated, up until now doctors have needed a separate piece of equipment for each different type of examination. But now, Rainer Schmitt and his team at the Fraunhofer Institute for Biomedical Engineering IBMT in St Ingbert have developed a modular ultrasound diagnosis platform that does away with the problem, a report in Fraunhofer Gesellschaft said. "In examinations with ultrasound", explains Peter K Weber of the IBMT, "sound waves are transmitted into the body via the sensor head. When the sound waves meet with the boundaries between different types of tissues — artries and internal organs, for example — diagnosis are derived from these acoustic data". PTI Cell phone de-activator Anew low-cost electronic unit has been developed by the Society for Applied Microwave Electronics Engineering and Research (SAMEER) to de-activate the operation of cell phone (mobile phones) in any identified area. The de-activator, which operates on very low power with battery back-up during power failure, will be useful to prevent cell phone operation in sensitive areas like cinema theatres, prayer halls and VIP conference rooms, R.K. Sinha, Director of SAMEER, which comes under the Union Ministry of Information Technology, told PTI. One de-activator covers an area of 10,000 sq feet and more units can be used for covering larger areas, Sinha said adding that it has been proved effective for all cell phones and for all service providers in the country. The instrument does not require any adjustments and is small and portable and most importantly it does not cause any damage to cell phones. PTI Docking station on a diet The SLIMDOCK PCGA-DSM5 docking station almost makes itself moot. Docking stations allow you to leave heacy components behind when you take your laptop, but even when the Slim Dock is mated to its Sony Vaio PCG-R505 ($ 3,099), the two measure just 2 by 11 by 9.4 inches and weigh 5.9 pounds. The $ 599 device is also the first to include a combo DVD and CD-RW drive. www.sony.com — Popular Science |
SCIENCE
QUIZ 1. This Germany-born U.S. physicist was known as "experimenting theoretician" and applied quantum concepts in the fields of specific heats of crystals, statistical thermodynamics, properties of free atoms, etc. Name this winner of the 1943 Nobel Prize in Physics for developing the molecular beam as a tool for studying the characteristics of molecules and for measuring the magnetic moment of proton. 2. Information gathered by a space probe launched three times by the Indian Space Research Organisation during the last seven years and the research done by an Indian team led by the world renowned astrophysicist Jayant Vishnu Narlikar have recently revealed that living bacterial cells keep on entering the earth’s atmosphere from space. These findings can be useful in studying life in and diseases from outer space. Name the institute the scientists of which have collaborated with Dr Narlikar in this pathbreaking discovery. 3. What is common between endosulfan, quinalphos, carbaryl, triazophos and dimethyoate? 4. How many species of snakes are there in the world? About how many of these are poisonous? What does the venom of a poisonous snake contain which is destructive for different body organs? 5. SPNs can be used to track inheritance of any disease, they contribute to traits that make us unique, and determine our susceptibilities to common diseases like diabetes, cancer and heart problems. What are SNPs which can also explain why individuals respond differently to drugs? 6. Contrary to popular belief, this part of the human body provides better identification than a fingerprint. Whereas a fingerprint has 40 different unique characteristics, a scan of this part has 256 such characteristics. Which is this part? 7. Eating fish may be a boon because ingredients present in some varieties of fish prevent diabetes, cancer and heart attack. Which are these ingredients? 8. It has been found that some plants, especially certain ferns, can "soak up" toxic wastes like arsenic from the soil and this process may prove to be very useful in cleaning up soil contaminated by industrial, mining, agricultural operations, etc. What is this process called? 9. This disease recently spread in north Bihar in epidemic proportions and has been in the news because of non-availability of standard drugs causing death of several persons. Which is this disease? Which main drug is recommended for its cure the use of which is also controversial? 10. IDPD is an organisation of Indian doctors that aims at elimination of the use of nuclear weapons throughout the world and stresses upon the nuclear power countries that the money thus saved should be utilised for health, education and other projects to improve the conditions of millions of people. What is the full name of this organisation? Answers 1. Otto Stern |