Nuclear radioactive particles from

The Characterization of Radioactive Particles from Nuclear Weapons Tests... 

Bartnicki J, Salbu B, Saltbones J, Foss A, Lind OC (2005) Atmospheric transport and deposition of radioactive particles from potential accidents at Kola nuclear power plant. Re-analysis of worst case scenarios. Norwegian Meteorological Institute, Oslo, Norway. Met.no research report No. 10/2005. ISSN-1503-8025... 

Gasiev, Y. L, Malakhov, S. G., Nazarov, L. E. and Silantiev, A. N., 1966 The size distribution of radioactive particles from nuclear weapon tests and their transport in the atmosphere. Tellus 18,474-485. 

I. Gasiev, S. G, Malakhov, L. G. Nazarov and A. N, Silantiev, The Size Distribution of Radioactive Particles from Nuclear Weapons Tests and Their Transport in the Atmosphere, Tellus 18 474 (1965). 

FIGURE 17.29 The main pathways by which humans may be exposed to radiation from a nuclear reactor incident. The wavy lines indicate direct exposure to radiation and the solid lines show transfer of radioactive matter. The two major ways in which humans are exposed are inhalation of radioactive particles from the cloud of radioactive materials or from windblown dust and from ingestion from food and drink. 

Nuclear activation analysis (NAA) is a method for qualitatively and quantitatively detg elemental compn by means of nuclear transmutations. The method involves the irradiation or bombardment of samples with nuclear particles or high-energy electromagnetic radiation for the specific purpose of creating radioactive isotopes from the stable or naturally-occurring elements present. From the numbers, types and quantities of radioactive elements or radionuclides, it is possible to deduce information about the elemental compn of the original sample... 

Radioactivity—Spontaneous nuclear transformations that result in the formation of new elements. These transformations are accomplished by emission of alpha or beta particles from the nucleus or by the capture of an orbital electron. Each of these reactions may or may not be accompanied by a gamma photon. 

Natural radioactivity derives from spontaneous nuclear disintegrations. Induced radioactivity derives from the bombardment of nuclei with accelerated subatomic particles or other nuclei. Both cause atoms of one nuclide to be converted to another nuclide. 

While nuclear power plants use multiple layers of protection from the radioactive particles inside the reactor core, a serious accident can cause the release of radioactive material into the environment. It is not a nuclear explosion, because the uranium fuel used in a nuclear power plant does not contain a high enough concentration of U-235. For an explosion to occur, the uranium fuel inside the reactor would have to be enriched to about 90% U-235, but it is only enriched to about 3.5%. 

Table II summarizes some of the features of the radioactive fallout processes in geophysical and astronomical settings. It seems that similarities do exist between the processes of formation of single particles from nuclear explosions and formation of the solar system from the debris of supernova explosion. We may be able to learn much more about the origin of the earth, by further investigating the process of radioactive fallout from the nuclear weapons tests.

Alpha particles from radioactive samples, or He2+ ons accc cralc(l n a cyclotron, may be used to bring about other nuclear reactions. For example, they may bombard a beryllium metal target ... 

FALLOUT (Radioactive . The term fallout generally has been used to refer to particulate mutter that is thrown into the atmosphere by a nuclear process of short time duration. Primary examples are nuclear weapon debris and effluents from a nuclear reactor excursion. The name fallout is applied both to matter that is aloll and to matter that has been deposited on the surface of the earfh. Depending on the conditions of formation, this material ranges in texture from an aerosol to granules uf considerable size. The aerodynamic principles governing tls deposition are the same as for any Other material of comparable physical nature that is thrown into the air. such as volcanic ash or particles from chimneys. Therefore, many of the principles learned in. studies of fallout from nuclear weapons can be applied lo studies of other particulate pollution in the atmosphere. 

Lockhart, L.,B., Patterson, R.L. Saunders, A.W. (1965) Distribution of airborne activity with particle size. In Radioactive Fallout from Nuclear Weapon Tests, ed. A.W. Klement Jr. CONF 765. N.T.I.S. Springfield, Va. 

Most radioactive particles and vapours, once deposited, are held rather firmly on surfaces, but resuspension does occur. A radioactive particle may be blown off the surface, or, more probably, the fragment of soil or vegetation to which it is attached may become airborne. This occurs most readily where soils and vegetation are dry and friable. Most nuclear bomb tests and experimental dispersions of fissile material have taken place in arid regions, but there is also the possibility of resuspension from agricultural and urban land, as an aftermath of accidental dispersion. This is particularly relevant to plutonium and other actinide elements, which are very toxic, and are absorbed slowly from the lung, but are poorly absorbed from the digestive tract. Inhalation of resuspended activity may be the most important route of human uptake for actinide elements, whereas entry into food chains is critical for fission products such as strontium and caesium. 

The cyclotron is a device in which positive ions are accelerated in a powerful magnetic field until they attain velocities of the order of thousands of miles per second. The use of such an instrument not only makes possible the use of particles other than the alpha particles from naturally radioactive elements but also serves to increase the fraction of effective impacts between ionic bullets and nuclear targets that bear like charges. 

Despite the safety regulations, accidents have occurred with nuclear reactors and reprocessing plants, primarily due to mistakes of the operators. By these accidents parts of the radioactive inventory have entered the environment. Mainly gaseous fission products and aerosols have been emitted, but solutions have also been given off. In the Chernobyl accident, gaseous fission products and aerosols were transported through the air over large distances. Even molten particles from the reactor core were carried with the air over distances of several hundred kilometres. 

Stable atoms can be converted into radioactive atoms by the collision of particles traveling at high speeds. In the early work the highspeed particles used were alpha particles from Bi (called radium C). The first nuclear reaction produced in the laboratory was that between alpha particles and nitrogen, carried out by Lord Rutherford and his collaborators in the Cavendish Laboratory at Cambridge in 1919. The nuclear reaction which occurs when nitrogen is bombarded vith alpha particles is the following ... 

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