Radioactive artificial

Radioactive elements may often be prepared artificially by bombarding the atoms of ordinary stable elements with, e.g. helium nuclei. See radioactivity, artificial. 

Radioactivity, Artificial—Man-made radioactivity produced by particle bombardment or nuclear fission, as opposed to naturally occurring radioactivity. 

Since not many natural radioactive elements are in existence analysis by radiochemical methods was rather limited until it became possible to "induce radioactivity artificially in some of the non-radioactive elements, as was first done in 1934 by I. Curie F.Joliot(Ref 1). This discovery greatly broadened the application of radiochemical analysis. The first application of artificial radio activation for the identification of constituents in a mixt was reported by Meinke (Ref 16) to have been done in 1936 by Hevesy 8t Levi (Ref 2). 

The scope of nnclear chemistry wonld be rather narrow if study were limited to natural radioactive elements. An experiment performed by Rutherford in 1919, however, suggested the possibility of producing radioactivity artificially. When he bombarded a sample of nitrogen with a particles, the following reaction took place ... 

The radioactivity of nuclides produced in this marmer is known as artificial radioactivity or induced radioactivity. Artificial radionuclides behave like natural radioactive elements in two ways They disintegrate in a definite fashion and they have a specific half-life. The Joliot-Curies received the Nobel Prize in chemistry in 1935 for the discovery of artificial, or induced, radioactivity. 

Radioactivity, artificial Man-made radioactivity produced by fission, fusion, particle bombardment, or electromagnetic irradiation e.g., radioactive fallout produced by fission of uranium and plutonium emits gamma radiation and alpha and beta particles. 

In this chapter we consider the structure of the nucleus. We shall examine in some detail the nature of the bond (force) holding nucleons together in nuclei, and the properties of the nuclei such as radioactivity, artificial transmutations, fission, and fusion. Where possible, this discussion is in terms of principles previously applied to the properties of atoms and molecules. 

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