翻訳と辞書 Words near each other ・ Neuvillers-sur-Fave ・ Neuvillette ・ Neuvillette, Aisne ・ Neuvillette, Somme ・ Neuvillette-en-Charnie ・ Neuvilley ・ Neuvilly ・ Neuvilly-en-Argonne ・ Neuvireuil ・ Neuvizy ・ Neutron depth profiling ・ Neutron detection ・ Neutron diffraction ・ Neutron economy ・ Neutron electric dipole moment ・ Neutron emission ・ Neutron flux ・ Neutron generator ・ Neutron howitzer ・ Neutron imaging ・ Neutron interferometer ・ Neutron magnetic moment ・ Neutron Man ・ Neutron microscope ・ Neutron moderator ・ Neutron moisture gauge ・ Neutron monitor ・ Neutron number ・ Neutron poison ・ Neutron probe Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク Neutron emission ： ウィキペディア英語版 Neutron emission Neutron emission is a type of radioactive decay of atoms containing excess neutrons, in which a neutron is simply ejected from the nucleus. Neutron emission is one of the ways an atom reaches its stability. An atom is unstable, therefore radioactive, when the forces in the nucleus are unbalanced. The instability of the nucleus results from the nuclei having extra neutrons or extra protons. Two examples of isotopes that emit neutrons are beryllium-13 (mean life ) and helium-5 (). Commonly, it is abbreviated with a lower case ''n''. As only a neutron is lost in this process, the atom does not gain or lose any protons, and so it does not become an atom of a different element. Instead, the atom will become a new isotope of the original element, such as beryllium-13 becoming beryllium-12 after emitting one of its neutrons. == Neutron emission in fission == Neutron emission usually happens from nuclei that are in an excited state, such as the excited 17O * produced from the beta decay of 17N. The neutron emission process itself is controlled by the nuclear force and therefore is extremely fast, sometimes referred to as "nearly instantaneous". This process allows unstable atoms to become more stable. The ejection of the neutron may be as a product of the movement of many nucleons, but it is ultimately mediated by the repulsive action of the nuclear force that exists at extremely short-range distances between nucleons. The life time of an ejected neutron inside the nucleus before it is emitted is usually comparable to the flight time of a typical neutron before it leaves the small nuclear "potential well", or about 10−23 seconds. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Neutron emission」の詳細全文を読む スポンサード リンク 翻訳と辞書 : 翻訳のためのインターネットリソース Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.