positron

From Longman Dictionary of Contemporary Englishpositronpos‧i‧tron /ˈpɒzətrɒn $ ˈpɑːzətrɑːn/ noun [countable] technical a very small piece of matter that has the same mass as an electron but has a positive electrical chargeExamples from the Corpuspositron• When an electron collides with a positron the two particles disappear, or annihilate, to create a high-energy photon.• The Dark Era begins when space is dominated by tiny particles such as photons, electrons and positrons.Origin positron (1900-2000) positive + -tron (as in electron)

单词	positron
释义	positron From Longman Dictionary of Contemporary Englishpositronpos‧i‧tron /ˈpɒzətrɒn $ ˈpɑːzətrɑːn/ noun [countable] technical a very small piece of matter that has the same mass as an electron but has a positive electrical chargeExamples from the Corpuspositron• When an electron collides with a positron the two particles disappear, or annihilate, to create a high-energy photon.• The Dark Era begins when space is dominated by tiny particles such as photons, electrons and positrons.Origin positron (1900-2000) positive + -tron (as in electron)
随便看	be under no obligation to do be under no obligation to do something be under par be under police etc guard be under pressure from be under pressure from to do be under pressure to do be under siege be under somebody’s care be under somebody’s thumb be under the impression be under the impression (that) be under the impression that be under threat of attack etc be under threat of closure etc be under threat of closure/attack etc be under thumb be under way be under your feet be understood be understood (that) be understood that be understood to be be understood to be (doing) something be understood to be doing