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What is taiga?

South of the treeless tundra in northern North America and Eurasia are huge tracts of coniferous forests, called the taiga. Most trees are evergreens, including fir, pine and spruce. These trees begin growth as soon as it becomes warm enough in spring, and they take full advantage of the short growing season. They are adapted to survive bitterly cold winters. …

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What is switchgrass?

Switchgrass, known in Botany as Panicum Virgatum L., is the perennial tall grass found in North America and Mexico. Its height varies from 5 ft to 12 ft, and the diameter of its stem at ground level is about 20 inches. It can grow in poor-quality soil, with low requirement of fertilisers, and can tolerate hostile conditions, including floods and …

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What is surface diffusion?

Surface diffusion is a general process involving the motion of adatoms (adsorbed atom lying on a crystal surface, used in surface chemistry, when describing single atoms lying on surfaces and surface roughness), molecules, and atomic clusters (adparticles) at solid material surfaces. Tunnelling diffusion is a particularly interesting example of an unconventional mechanism wherein hydrogen has been shown to diffuse on …

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What is summer ploughing?

Ploughing one month in advance i.e. in the month of May for kharif crops is known as summer ploughing. There are the three usual harvests known as the kharif or autumn (June-September), the rabi or spring (October-March) and zaid or extra harvest (March-June). Summer ploughing helps to kill weeds, hibernating insects and diseasecausing organisms by exposing them to the summer …

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What is Strepulsion Physics?

In the 17th century, Sir Isaac Newton discovered the universal gravitational force. In the 21st century, Navinchandra K Shah, Prof. P N Jain and Prof. P P Jain of Hubli discovered a universal repulsion force (URF). It’s an astronomical force exerted by the sun and stars and therefore called stellar repulsion force (SRF). The science which deals with repulsive phenomena …

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What is Stevenson’s Screen?

Stevenson’s Screen is a wooden box fitted into a steel frame, specially designed to protect weather instruments like thermometer, barometer, etc. from the sun’s rays and other natural heat radiation. British civil engineer Thomas Stevenson designed the first Stevenson’s Screen in 1818. In order to prevent direct sunlight falling on the instruments, it was designed so the door opens to …

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