| 释义 |
DictionarySeeCNO cyclecarbon-nitrogen cycle
carbon-nitrogen cycle[¦kär·bən ¦nī·trə·jən ‚sī·kəl] (nuclear physics) A series of thermonuclear reactions, with release of energy, which presumably occurs in stars that are more massive than the sun; the net accomplishment is the synthesis of four hydrogen atoms into a helium atom, the emission of two positrons and much energy, and restoration of a carbon-12 atom with which the cycle began. Also known as carbon cycle; nitrogen cycle. carbon-nitrogen cycle
carbon-nitrogen cyclen. A chain of thermonuclear reactions in which nitrogen isotopes are formed in intermediate stages and carbon acts essentially as a catalyst to convert four hydrogen atoms into one helium atom with the emission of two positrons. The entire sequence is thought to generate significant amounts of energy in the sun and certain other stars. Also called carbon cycle, nitrogen cycle. |