Nuclear meltdown — Three of the reactors at Fukushima I overheated, causing core meltdowns. This was compounded by hydrogen gas explosions and the venting of contaminated steam which released large amounts of radioactive material into the air.[1] … Wikipedia
radiation measurement — ▪ technology Introduction technique for detecting the intensity and characteristics of ionizing radiation, such as alpha, beta, and gamma rays or neutrons, for the purpose of measurement. The term ionizing radiation refers to those… … Universalium
Nuclear reactor physics — See also: Critical mass Nuclear reactor physics is the branch of science that deals with the study and application of chain reaction to induce controlled rate of fission for energy in reactors. Most nuclear reactors use a chain reaction to induce … Wikipedia
Conversion of units — is the conversion between different units of measurement for the same quantity, typically through multiplicative conversion factors. Contents 1 Techniques 1.1 Process 1.2 Multiplication factors … Wikipedia
Réaction en chaîne (nucléaire) — Pour les articles homonymes, voir Réaction en chaîne. Schéma d une réaction en chaîne de fission nucléaire 1. Un atome d uranium 235 absorbe un neutron … Wikipédia en Français
Life Sciences — ▪ 2009 Introduction Zoology In 2008 several zoological studies provided new insights into how species life history traits (such as the timing of reproduction or the length of life of adult individuals) are derived in part as responses to… … Universalium
Mathematics and Physical Sciences — ▪ 2003 Introduction Mathematics Mathematics in 2002 was marked by two discoveries in number theory. The first may have practical implications; the second satisfied a 150 year old curiosity. Computer scientist Manindra Agrawal of the… … Universalium
nature, philosophy of — Introduction the discipline that investigates substantive issues regarding the actual features of nature as a reality. The discussion here is divided into two parts: the philosophy of physics and the philosophy of biology. In this… … Universalium
IMMUNITÉ ET SYSTÈME IMMUNITAIRE — Le système immunitaire assume l’une des grandes fonctions physiologiques des Vertébrés: l’aptitude à la reconnaissance d’un nombre prodigieux de structures moléculaires distinctes, les antigènes. Un antigène est classiquement réputé « étranger »… … Encyclopédie Universelle
List of electronics topics — Alphabetization has been neglected in some parts of this article (the b section in particular). You can help by editing it. This is a list of communications, computers, electronic circuits, fiberoptics, microelectronics, medical electronics,… … Wikipedia
ISOTOPES — Les atomes sont constitués d’un noyau autour duquel gravitent Z électrons. Le noyau atomique est lui même composé de Z protons portant chacun une charge positive unité et de N neutrons non chargés. Les masses du proton et du neutron étant… … Encyclopédie Universelle