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| SCIENCE TRIBUNE | Thursday, July 26, 2001, Chandigarh, India |
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Washing
machines get better Novel
hardware device NEW PRODUCTS &
DISCOVERIES
SCIENCE QUIZ |
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Will the NMD shield hold? ONE can well imagine that if our present-day nuclear weapons are so dangerous and potent, a shield made to protect you from those nuclear bombs has to be something exceptionally sophisticated and strong. Nuclear missile shield was the dream of former US President Ronald Reagan. He believed that his engineers and scientists will be able to develop such laser weapons and defensive methods which will provide complete protection to his land and people. Similarly this shield could also be offered to other friendly nations. After land, sea and air, the next question battle field in space. This is unfortunately the most ridiculous use of space. And it is the most expensive military project ever undertaken in the history of mankind! Strategic defence initiative, first announced in 1981, is nothing else but Nuclear Missile Defence (NMD) shield. Also famous by the name “star wars”, this strategy is often misconceived by some people to be a technology full of fancy starships zooming in space and fighting battles with red and blue laser beams, as in films. Present-day nuclear bombs are mostly delivered by long-range ballistic missiles, since missile is far more efficient, fast and precise than an aircraft. Today hundreds of missiles are desperate to reach their targets. They are loaded with several megatons of nuclear explosives. They can travel 13,000 km in half an hour, which means very little time to take defensive measures. So a defensive shield ought to be far more active and efficient. The flight of a ballastic missile can be divided into three phases viz. I. Boost phase, 2. Mid course phase, 3. Terminal phase. NMD has devices and strategies to destroy these missiles in three phases! This requires scanning, detection and location of any air borne weapon all over the globe 24 hours a day. Many such satellites and ground stations will do this on microwave and infrared band. They will also use some advance laser devices for detection, such as free electron, laser, X-ray laser, Xenon fluoride lasers etc which would be reflected from reflectors put up on satellites. This would enable the detection of a launched missile anywhere on the globe almost in no time. Since the time for decision and action is very short, a huge volume of data would have to be transferred from one point to another for processing and therefore most advanced supercomputers would be involved. To destroy the enemy missile in the boost itself would be the first preference. But if it escapes in the boost phase (the time when the missile is launched and is gaining momentum), it would immediately be destroyed in the mid course phase (the time taken by a missile to be travel to the destination), since a ballistic missile always comes out of the atmosphere during its boost phase and therefore it could become an easy prey for the satellites orbiting around the earth and fitted with powerful laser devices. Since it is a must for the defence shield to destroy enemy missile in terminal phase (when a missile is straight forward heading towards its target), therefore many Deuterium fluoride laser devices each of the power of several megawatt would be eagerly waiting to pour out their energy on the missile. They will be jointed by the electron beam lasers, X-ray lasers, plasma guns, microwaves etc. Hundreds of thousands of bullets would be shot in unison, like a cloud of bullets. These bullets will get momentum by the laser by the devices and may travel at 1,200
m/second. Electromagnetic railguns will shoots projectiles with velocities of the order of 10 km/sec or more. Still there are doubts. Will shield hold? Whether it will definitely protect us or not? Machines can be fooled sooner or later. Dummy missiles can be launched to be followed by real ones, later or several missiles can be launched simultaneously from most distant places on the globe. Some believe that star wars strategy is to complicated to take a practical shape. Well, so much about present-day defence shields. Let’s see that what kind of shields we can expect in future. In science fiction a force field is a defensive barrier of energy which protects against some weapons, and sometimes against all! But in reality, like gravity they simply are the stresses in space. In real world there are only four kinds of forces fields viz 1. Strong nuclear force (which holds all protons and neutrons together inside a nucleus of an atom), 2. Next, around 140 times weaker is the electromagnetic force (which holds atoms in all chemicals), 3. Next is the weaker nuclear force, 4. And weakest of all (some 1039 times weaker) is gravity. To switch on an artificial gravity field we would have to create mass or energy...simply impossible. So therefore those very useful “Tractor-Beams” used to pull along objects in star-trek also seen impossible. Also its companion force field gadget is the “Pressor-Beam” which pushes things away, and is even less plausible. Thus we are left with electromagnetic force which can achieve very few of the feats of the fictional force fields. A sufficient powerful oscillating magnetic filed would require huge and numerous electromagnets and would indeed melt objects approaching it but only slow moving objects like swords and fast moving bullets will pass through it unaffected! No doubt powerful electrostatic fields would repeal bullets too if the bullets were given an electric charge of the same sign before firing. Obviously enemy wouldn’t give them any charge! On the contrary the person being protected by the electric field would instantly be killed when its field discharges into the earth in a colossal lightening bolt. Magnetic fields might deflect charged particle beams but such powerful fields can be made in a small space, between the poles of the magnets — useless as a practical defence. Photons of lasers are unaffected by the magnetic fields — only centimetres of steel or kilometres of air will stop them. Of course we should use a mirror! Science fiction has invented some new forces such as electro-gravitic force and magneto-gravitic force. But unified field theories, which try to connect and explain four basic forces have so far had small success with gravity. It seems doubtful that some new kinds of forces and energies could have been left undiscovered! But it is sure that we are finding solutions to those problems which we have created ourselves. Very few people are desperate to raise shields against natural disaster, against ageing process, against diseases, against evils of society...! |
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Washing machines get better RESEARCHERS
have developed a washing machine with a new system of two drums rotating in opposite directions to replicate the movement of handwashing thereby promising a revolutionary action on clothes. The Contrarotator, a yellow and purple space-age looking machine, is claimed to be the first of its kind designed to imitate the action of handwashing by twisting and flexible clothes, thereby opening the material to detergents. The idea of the design came after the inventor James Dyson from Dyson Appliances, UK (the company which designed the best-selling, revolutionary bagless vacuum cleaner) tested various methods of washing clothes including pummeling, scraping and rubbing before deciding that washing machines gave a poorer performance than human power. He found that 15 minutes of handwashing got cleaner than 67 minutes in the best washing machine, a report in British Commercial News said. “It is shocking that your hands can wash cleaner than your machine,” explained Dyson. “We found out why — hands knead the fabric properly to release the dirt. We discovered that with a second drum going in the other direction we could even improve on handwashing.” To replicate the movement of handwashing, he patented two aligned drums and engineered them to rotate in opposite directions at the same time. The effect of this revolutionary action on clothes is dramatic. Instead of revolving in the old single-drum pattern, the clothes in the two drums are much more active, moving in an infinitely variable pattern, to flex the fabric and open the weave to the detergent. The result is cleaner clothes in as little as half the time. An ordinary machine has a single drum which can only go round in one direction at a time, taking the clothes with it. On each circuit, the clothes drop to the bottom of the drum, bundling clothes at the base of the machine. With so little actual washing action, the clothes need an extended soak in detergent to get clean. The machine has double-sized drums and is therefore the only machine big enough to wash a king-size devout, with a 60 per cent larger drum capacity than the best-performing washing machines. It releases dirt more quickly, so it can wash in as little as half the time, reducing a typical weekly wash of 15 kilograms down from almost six hours to just over two hours, saving about three and half hours. Other innovative features include a built-in jack and trolley to manoeuvre the machine, a coin trap to capture buttons and coins and the absence of a rubber seal which often marks and damages clothes.
PTI |
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Novel hardware device SCIENTISTS have developed a hardware encryption device, the size of a credit card, that can also be used in laptops besides operating extremely fast and effectively. Modern and powerful encryption processes protect company data and confidential information exchanged over the internet from unauthorised access by third parties. Extremely powerful mathematical algorithms are used today to encrypt important data. They convert a text or other sequence of characters into an apparently random sequence of numbers and letters, which are meaningless, a report in Fraunhofer Gesellschaft said. Only authorised recipients, equipped with the appropriate electronic decryption key, are able to reconstruct the original information. However, a new process now in common use is the synchronous “Data encryption Standard” (DES), whereby synchronous in this case means that one and the same key is used for encryption and decryption.
PTI |
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NEW PRODUCTS & DISCOVERIES A large asteroid, named Varuna after the lord of the cosmos in Hindu mythology, has been spotted in the outer fringes of the Solar System, a discovery which suggests the sun may have more than nine planets, reports AFP. Astronomers say Varuna was detected last November by Arizona-based astronomers in the Spacewatch Project, a scheme aimed at scouring the asteroid belts to look, in part, for rogue rocks that could be a potential threat to Earth. The spherical object is 900
kilometer in diameters, which makes it only a tad smaller than Gharon, the tiny moon (1,200 kms across) that orbits Pluto, the most distant of the Sun’s nine known planets. The discovery, by a team led by David Jewitt of the Institute of Astronomy in Honolulu, was reported in Nature, the British science weekly. Until 1992, Pluto and Charon were the only known objects in the Kuiper Belt, an ancient ring of icy bodies believed to be have been formed from the outer reaches of material that swirled around the infant Sun billions of years ago. Since then, more than 400 other Kuiper Belt objects have been discovered by powerful telescopes. But astronomers suspect the belt could hold hundreds of thousands of rocks 100 km across, and possibly billions of others 10 km across. The biggest handicap to identifying them has been the poor reflectivity of these objects. They are so far from the sun that solar rays are terribly weak, and many of the objects themselves are dark, which means that they reflect very little light to enable astronomers to identify and measure them. In Varuna’s case, the asteroid was easy to spot because it shone brightly, thanks to its reflective surface.
PTI
High-speed cargo vessels EVER
ORDER A big-ticket item from Europe and wonder, weeks later, if the ship took the long way? We’re not surprised: It takes a full eight days for a freighter to cross the Atlantic. But high-speed cargo vessels from FastShip Atlantic promise to cut the trip in half. The ships have a V-shaped how and a shallow concave rear that lift the stern out of the water to reduce drag. They cruise at 40 knots even through 24-foot-high waves. The first will launch in late 2004.
Popular Science
Galactic “baby boom” An Indian research scholar has found a ‘baby boom’ in the universe. This bumper crop of “infant” galaxies may help scientists develop new insight into the beginning of galaxy formation. Reporting this to the American Astronomical Society in Pasadena, California, postdoctoral fellow Sangeeta Malhotra and her colleague James Rhoads said this finding is the largest to date of very distant and highly energetic young galaxies. They found 150 in a full-moon-sized path of sky. “It’s great to have found such a large number of these galaxies, because it is going to be harder to shove them under the rug”, said Sangeeta, a Hubble fellow in the Krieger School of Arts and Sciences at the Johns Hopkins University. “We are going to have to think harder about what’s happening in galaxy formation and star formation at these times, early in the history of the universe”, she said. Among the key questions will be what makes the young galaxies so bright: intense bursts of star formation, the activity of a massive black hole at the centre of the galaxy or something else? “In about half of these galaxies, our models of how stars behave can’t explain the strength of a characteristic spectral line we use to identify them”, Sangeeta said.
PTI
Starch to control
mosquitos breeding Researchers have found that powdered starch could clean-up mosquito control. Xanthan gum, a thickening agent usually found in processed foods such as salad dressing, kills pond-dwelling mosquito larvae as effectively as conventional insecticides, say Barry Pittendrigh at Purdue University in Indian and his team at the US Fish and Wildlife Service’s Prime Hook National Wildlife Refuge in Delaware. Sprinkled on mosquito breeding grounds, it forms a temporary film on the water surface that smothers these blood-sucking pests without affecting other pond life, they report in Environmental Entomology. The first field test of carbohydrate-based mosquito control will interest those looking for safer, greener ways to rein-in malaria risk, Rising insecticide resistance among mosquitoes, and the toxicity of certain insecticides, particularly DDT, used in some developing countries, is making malaria increasingly difficult to control. Previous research has turned up other natural mosquito killers, such as peppermint and lemon oils; many flopped commercially because the quantities needed were too high or because they killed too many other insects as well. The same challenges face starch-based mosquito killers. But the researchers argue that starch could act as a floating carrier for conventional insecticides, preventing the chemicals from sinking below the surface of water, where they are no longer effective but can harm other organisms.
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SCIENCE QUIZ 1. This Indian engineer, though working mainly in the USA, won 40 patents in printing technology. He made so many other inventions in different fields that American technologists often referred to him as ‘Indian Edison’. Can you name him? 2. These animals are a variety of large lizards found in hot deserts and live in holes they dig in the ground. They rarely drink water and the moisture absorbed through their skin and the fluids in their food are normally sufficient to meet their requirements. But during the prolonged drought in some desert areas of Rajasthan, no moisture is left in the ground and these animals come out on hot roads in search of illusory mirage pool of water and get killed by the passing vehicles. Which are these animals? 3. The oil extracted from the seeds of a plant has already been successfully used as a fuel for diesel — based generators by scientists in Bangalore. Now some states are planning to grow this plant on a large scale with a view to generating power from the oil of this plant in rural areas at a much lesser cost than from diesel. Which is this plant? 4. Luca’s reagent is used to distinguish between primary, secondary and tertiary alcohols. What is Luca’s reagent? 5. What is a compound of an alkali metal with a carboxylic acid of high molecular weight (for example, sodium or potassium salt of oleic or palmitic acid) usually called? 6. A unit of measurement of an electrical quantity is named after a French physicist and mathematician who devised the earliest type of galvanometer. Name this unit. 7. This water body is the only place in the world that has an oxygen-rich atmosphere around it. Its water and mud contain salts like chlorides, bicarbonates, sulphates etc. of sodium, potassium, calcium and magnesium. Thus its contents are useful in treating certain skin diseases and disorders of joints, in relaxing nervous system, for healing wounds and have some other curative properties. Which large water body are we talking about? 8. These objects in the solar system are classified into “Groups”, “Stones”, “Irons” and “Stony Irons”. Which are these objects? 9. Certain animals such as wall lizard, prawn, crab and squilla break off their tail or any appendage when they are disturbed in other animal. What is this phenomenon called? 10. CSIRO is an organisation of some countries which conducts research in latest fields of science. What is the full name of this organisation? Answers
1. Bhise Shankar Abaji 2. Desert monitors, locally called “gohara” 3. Pongamia (Honge) 4. Anyhydrous zinc chloride dissolved in concentrated hydrochloric acid 5. Soap 6. Ampere (unit of current, symbol A) 7. Dead Sea 8. Meteorites 9. Autotomy 10. Commonwealth Scientific and Industrial Research Organisation. |
