منابع مشابه
Background radiation, people and the environment
All living organisms are exposed to ionizing radiation comprising cosmic rays coming from outer space, terrestrial nuclides occurring in the earth’s crust, building materials, air, water and foods and in the human body itself. The exposures are constant and uniform for all individuals everywhere including the dose from ingestion of 40K in food. Cosmic rays are, more intense at higher alt...
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The observed cosmic microwave background (CMB) radiation provides strong evidence for the hot big bang. The success of pri-mordial nucleosynthesis calculations (see Sec. 16, " Big-bang nucle-osynthesis ") requires a cosmic background radiation (CBR) characterized by a temperature kT ∼ 1 MeV at a redshift of z ≃ 10 9. In their pioneering work, Gamow, Alpher, and Herman [1] realized this and pred...
متن کاملCosmic Background Radiation Due to Photon Condensation
It is shown that a collection of photons with nearly the same frequency exhibits a Bose ”condensation” type of phenomenon at about 3K corresponding to a peak intensity at a wave length of about 0.4cm. This could give a mechanism for the observed Cosmic Background Radiation, and also explain some curious features. It is a curious circumstance that the substitution of the cosmic microwave backgro...
متن کاملGamma background radiation in Yazd province A preliminary report
ABSTRACTBackground: There are relatively rich uranium mines in regions of Saghand and Bafgh in Yazd province. This survey was carried out to provide a map of ambient gamma radiation of Yazd province and the probable effects of the existence of these mines on background radiation dose rates.Materials and Methods: The measurements of the outdoor and indoor–environmental exposures (including cosm...
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Parsing Expression Grammar (PEG) encodes a recursivedescent parser with limited backtracking. Its properties are useful in many applications. In its appearance, PEG is almost identical to a grammar in the Extended Backus-Naur Form (EBNF), but may define a different language. Recent research formulated some conditions under which PEG is equivalent to its interpretation as EBNF. However, PEG has ...
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ژورنال
عنوان ژورنال: Nature
سال: 1975
ISSN: 0028-0836,1476-4687
DOI: 10.1038/254383a0