In nuclear engineering, a neutron moderator is a medium that reduces the speed of fast neutrons, ideally without capturing any, leaving them as thermal neutrons with only minimal (thermal) kinetic energy. These thermal neutrons are immensely more susceptible than fast neutrons to propagate a nuclear chain reaction of uranium-235 or other fissile isotope by colliding with their atomic nucleus.
"Light water" is the most commonly used moderator (roughly 75% of the world's reactors) although the term is slightly ambiguous, usually meaning natural fresh water, but could also refer to deuterium-depleted water. Solid graphite (20% of reactors) and heavy water (5% of reactors) are the main alternatives.Beryllium has also been used in some experimental types, and hydrocarbons have been suggested as another possibility.
Habari wakuu, naomba mnisaidie wala sihitaji masimango.
Nina ndoto za kuishi nje ya Tanzania, naona njia nzuri ya kuishi Ulaya ni kuomba udhamini wa elimu kwenye vyuo vya nje.
Nilifeli form 4, hapa nina miaka 23 sasa na ninawaza nirudi shule (QT). Je, naweza toboa kwa umri huu?
Klabu ya Simba leo Jumapili February 13 inashuka kwenye uwanja wa Benjamin Mkapa kucheza na ASEC Mimosas kutoka Ivory coast, kwenye mchezo wa kwanza hatua ya makundi Kombe la Kombe la Shirikisho Barani Afrika CAFCC.
Hautakuwa mchezo mwepesi, bali utakuwa mgumu na wa kusisimua hasa ukizingatia...