Thursday, December 5, 2013
Theory begins some 50 million years back.
Dr. Nitish Priyadarshi.
One of my friends suggested me to become non-vegetarian. He gave the interesting example about the benefit of becoming non- vegetarian. He said that all non-vegetarian animals like tiger, cheetah, wolfs are slim compared to vegetarian animals like buffalo, elephant, zebras etc. I started searching the mystery of why vegetarian animals are so fat? Some theories are hidden in pages of time million years back.
Why did some prehistoric animals get so big in the first place? No one knows for sure, but there are lots of theories. One theory begins some 50 million years back.
The past 50 million years appear to have been a time of progressive deterioration. On every vegetated continent, grasses and small hard leaves widened their domain. While certain herbivores accommodated to the new foliage- and evolved the art of eating coarse, fibrous fodder-other species, committed to Eocene and Oligocene ways, died. In many animals, from horses and zebras to rodents, from antelopes to kangaroos, from giraffes to camels, from elephants to pigs, the main food-processing part of the jaw, the cheek teeth, became larger in over-all height and riddled with complex slicing edges. An increase in tooth height, called hypsodonty (high tooth) is typical of animals that harvest greenery close to the ground-mainly fibrous grasses in open territory which is generally poor in nutritional value.
Any animal committed to such a diet must eat an enormous quantity. This requires both a large gut and a large body capable of handling masses of grass and other fibrous plants. Long –distance travel allowed access to such volumes of vegetation, mowed and chewed as the animal walked along. After the Eocene, many lineages of animals evolved to a large size, formed social herds, and modified their limb bones in ways that allowed wide and rapid movements over open terrain.
The other theory says being larger can provide many evolutionary advantages—bigger animals are less vulnerable to predators and can compete more assertively for resources. The existence of bigger herbivores also means that carnivorous animals have to grow in order to be effective hunters. A species' size may also shift in response to environmental factors. In cold climates, a bulky frame can be an asset to warm-blooded animals—the bigger they are, the better they retain heat. The opposite is true for cold-blooded animals—in a warm climate, a bigger mass can help insulate an animal and keep it from overheating. Scientists suggest that some plant-eating dinosaurs and other animals might have gotten so big because the foliage in that era was extremely tough and woody: A larger body frame meant a longer digestive tract and more time for bacteria to do its work, allowing the dinosaur to extract as much nutritional value as possible from each bite.
Thursday, November 21, 2013
People confused it with flying object or a satellite.
Dr. Nitish Priyadarshi
Few of my friends call me up to know about the bright object in the sky above Ranchi city. They confused it with some flying object or a satellite. It is Venus, I told them. It’s the planet which is easily visible at nightfall around the world in early November. Venus continues to draw all eyes to the western sky after sunset. Observers have been watching the bright planet for many weeks, although it seems that a fairly large percentage is not quite sure exactly what they have been looking at. Venus has increased noticeably in recent days. Venus beams mightily in the west at dusk, as seen from across the Earth. You can’t miss it. It sets roughly two-and-one-half-hours hours after sunset at mid-northern latitudes in early November and close to three hours after the sun by the month’s end. Venus! It’s the beautiful “evening star.”
The best time to observe Venus is actually in the early morning or early evening before the sky gets too dark. This is because Venus is so bright that it can actually be more difficult to see its features with the large contrast between it at the night sky, and it is best to catch it with some twilight behind it.
Venus is the second planet from the Sun, orbiting it every 224.7 Earth days. It has no natural satellite. It is named after the Roman goddess of love and beauty. After the Moon, it is the brightest natural object in the night sky. Venus is a terrestrial planet and is sometimes called Earth's "sister planet" because of their similar size, gravity, and bulk composition (Venus is both the closest planet to Earth and the planet closest in size to Earth). However, it has also been shown to be very different from Earth in other respects. It has the densest atmosphere of the four terrestrial planets, consisting of more than 96% carbon dioxide. Venus may have possessed oceans in the past, but these would have vaporized as the temperature rose due to a runaway greenhouse effect.
Monday, November 4, 2013
Air pollution likely to increase by 30 to 35%.
Dr. Nitish Priyadarshi
Toxic fumes due to burning of firecrackers.
Such firecrackers generate more smokes.
Diwali was celebrated in Ranchi city of Jharkhand State in India with fun on Sunday. Firecrackers were used to celebrate this festival. Ranchi sky was covered with smokes due to burning of fire crackers. These smokes may contain toxic and heavy metals which can affect human health. Firecrackers contain elements like copper, cadmium, sulphur, aluminium, barium and various other such elements that help in releasing vibrant colours after it is ignited, causing a host of health problems. Once a cracker is burnt, it releases toxic chemicals that remain suspended for a long time causing serious health aliments.
As diwali is festival of lights, people consider it as festival of Firecrackers. Firecrackers come in different varieties from the delightfully visual ones to the ear deafening noisy ones.
Our tradition use firecrackers in diwali cause of reasons, possible reason and a more scientific one for lighting firecrackers is that the fumes produced by them kill insects and mosquitoes found after the rains. But now people use firecrackers in an amount that it harming the mankind, environment, increasing the pollution.
During Diwali, the air pollution in Ranchi level is likely to increase by 30 to 35 %, which will not only be dangerous for those suffering from pulmonary diseases, but also cause breathing problem to others.
Harmful effects of firecrackers
1) Health hazards: Burns, deafness, Nausea and mental impairment. Many people die in explosions in factories manufacturing fire-crackers.
Firecrackers can cause hearing loss, high blood pressure, sleeping disturbances and sudden exposure to loud noise can cause temporary or permanent deafness or even result in heart attack.
2) Sometimes, rocket-crackers set fire to huts, heap of dry grass etc. this happen mostly to country side
3) Noise pollution: firecrackers make noise more than the allowed decibel limit for human being.
4) Smog caused by firecrackers may be harmful to inhale.
5) It increases the Pollution in environment
The firework reaction products that are emitted are deposited and thus enter the soil, crops and, in the case of fireworks over water, standing waters.
Tuesday, October 29, 2013
Rivers flowing through Ranchi plateau may also contain thorium.
Dr. Nitish Priyadarshi
Thorium deposits in India.
River flowing near Ranchi city.
Pegmatite intrusions in host rocks in Ranchi plateau.
Thorium is a naturally occurring radioactive chemical element with the symbol Th and atomic number 90. It was discovered in 1828 by the Norwegian mineralogist Morten Thrane Esmark and identified by the Swedish chemist Jöns Jakob Berzelius and named after Thor, the Norse god of thunder. Thorium produces a radioactive gas, radon-220, as one of its decay products. Secondary decay products of thorium include radium and actinium. In nature, virtually all thorium is found as thorium-232, which undergoes alpha decay with a half-life of about 14.05 billion years.
Berzelius was quite unaware of the tremendous amount of power that this element stores within it. Subsequent development in the field of nuclear science and technology, however, revealed that thorium might well prove to be equal to the god after whom it was named.
Thorium, which is transmutated U-233 in a breeder reactor, can be used as a nuclear fuel. It is presumed that with the development of breeder technology, thorium will come to play a vital role in providing electric power to millions.
Thorium is widely distributed in the earth’s crust with an average abundance of 8 ppm (parts per million) and is usually associated with uranium or the rare earth-earth elements. The principal mode of occurrence is in the form of veins in granites, synites, pegmatites and other acidic intrusions containing thorium- bearing minerals, such as thorite, thorianite, uranothorite and monazite. Detrital monazite occurs in quartz-pebble conglomerates, beach placers, inland placer deposits and dunes.
The largest known reserves of the thorium are contained in the beach and inland placer deposits of monazite, which are exploited for their rare-earth and ThO2 contents. Placer deposits of monazite are found in Australia, Egypt, India, Liberia, Brazil, Malaysia and the USA (Florida).
Among the inland placer deposits containing heavy mineral there are two appreciable concentrations of monazite, which are located in the Ranchi plateau of Jharkhand and the Purulia planes of West Bengal. These occurrences cover an area of about 608 sq. km. forming a thin cover of an average depth of about 50 cm (which may be locally up to 2m.). These deposits have been formed due to the weathering and erosion of Precambrian gneisses and schists, intruded by pegmatites and porphyritic granites, which are enriched in monazite and other associated heavy minerals.
The placer minerals are released from their matrix by weathering. The comminuted materials are washed slowly down slope to the nearest stream or to the seashore. Moving stream water sweeps away the lighter matrix, and the heavier placer minerals sink to the bottom or are moved downstream relatively shorter distances. The sands of the rivers like Swarnrekha, Jumar, Potpoto, kanchi, etc. flowing through Ranchi plateau may contain thorium in considerable amount.
Thorium present in the river streambed sediments are mostly of terrestrial origin and their concentrations are related to the type of parent rocks and to the genesis of the sediments. The river sediments generally exhibit large variation in composition. This variation can be related to the chemical and mineralogical evolution of these sediments along the river, influence of tributaries, or different properties of drained soil. The mobility of radionuclides in the aqueous system is an important factor influencing the content of radionuclides in river sediments. Surface run-off waters in the tributaries wash down a part of deposited radionuclides and finally store them in the river sediments.
Most of the radioactive anomalies in the Damodar Valley basins are confined to the Panchet sandstones with the preponderance of thorium over uranium. A similar pattern has also been observed in the Barakar sediments of the Hutar basin.
The granites of the provenance areas fir the Hutar-Daltonganj basins contain anomalous uranium values. Uranium mineralization has also been observed in the granitic rocks comprising the southern periphery of the Hutar basin. The Proterozoic granitoids, forming the provenance for the Hutar and Auranga sub basin (Jharkhand), have been analysed which revealed uranium content up to 520 ppm, while the clays and sandstones of Barakar Formations have revealed anomalous uranium-thorium values of the order of 120-150 ppm uranium and less than 100-800 ppm thorium.
Bateman, A.M. 1955. Economic mineral deposits. John Wiley & Sons, Inc. New York.
Virnave, S.N. 1999. Nuclear geology and atomic mineral resources. Bharti Bhawan, Patna.
Viswanathan, G., Badri, N.S.R., and Virnave, S.N. 1989. Radioelement distribution in the Lower Gondwana sediments of Hutar basin, Palamau district, Jharkhand; its bearing on uranium exploration. Exploration Research Atomic minerals Vol. 2 , pp 121-131.