Microcosmology Atom in Jain Philosophy and Modern Science

Author(s): Jethalal S Zaveri, Mahendramuni
Publisher: Jain Vishva Bharati

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Microcosmology : Atom
thousand miles per second to less than one mile per second by being made to pass through a moderator before they reach the atoms at which they are aimed. Thus the liberation of neutrons is under complete control and acts as a slow but steady nuclear fire.
.. The uncontrolled chain reaction is one in which there is no moderator -and no neutron-absorbers. It is analogous to the dropping of a match in a petrol tank. In the uncontrolled chain reaction the fast neutrons with nothing to slow them down or to devour them, build up by the trillion and quadrillion in a corresponding number of atoms, resulting in the release of unbelievable quantities of nuclear energy at a tremendously explosive rate.
It can be concluded from the general theory of nuclear structure that the fission effectiveness of neutrons increases with the increasing atomic weight of the element in question. Thus, the fission of uranium nuclei gives on the average a cent percent result; plutonium, a still heavier element would give a better result. If with each new generation the number of neutrons grows by, say, about 50 percent, there will be enough of them to attack and break-up any single nucleus of the material. This is called the progressive branch chain reaction and the substance in which such a reaction will take place is called fissionable substance. Among all the variety of nuclear species existing in nature, there is only one type of nuclei where such reaction is possible. These are the nuclei of the famous isotope of uranium, U-235, the only natural fissionable substance.
Other fissionable substances, not existing in nature, have been artificially built. An artificial element which is known as Plutonium has the atomic number 94 and is even more fissionable than U-235. It is obtained by transforming the nucleus of natural uraniumn.
Another artificial fissionable substance U-233 is obtained by similar transformation of the nuclei of natural radio-active element Thorium (Th-232). In fact, it is possible, in principle at any rate to turn the entire supply of natural uranium and thorium into fissionable products which can be used as concentrated sources of nuclear energy.