absorption négative
21drug — drug1 /drug/, n., v., drugged, drugging. n. 1. Pharm. a chemical substance used in the treatment, cure, prevention, or diagnosis of disease or used to otherwise enhance physical or mental well being. 2. (in federal law) a. any substance… …
22Drug — /droog/, n. Zoroastrianism. the cosmic principle of disorder and falsehood. Cf. Asha. [ < Avestan drauga] * * * I Any chemical agent that affects the function of living things. Some, including antibiotics, stimulants, tranquilizers,… …
23radiation — radiational, adj. /ray dee ay sheuhn/, n. 1. Physics. a. the process in which energy is emitted as particles or waves. b. the complete process in which energy is emitted by one body, transmitted through an intervening medium or space, and… …
24chemical compound — Introduction any substance composed of identical molecules consisting of atoms (atom) of two or more chemical elements (chemical element). All the matter in the universe is composed of the atoms of more than 100 different chemical elements …
25endocrine system, human — ▪ anatomy Introduction group of ductless glands (gland) that regulate body processes by secreting chemical substances called hormones (hormone). Hormones act on nearby tissues or are carried in the bloodstream to act on specific target organs… …
26Refractive index — Refraction of light at the interface between two media. In optics the refractive index or index of refraction of a substance or medium is a measure of the speed of light in that medium. It is expressed as a ratio of the speed of light in vacuum… …
27Photoresist — A photoresist is a light sensitive material used in several industrial processes, such as photolithography and photoengraving to form a patterned coating on a surface. Contents 1 Photoresist categories 1.1 Tone 1.2 Developing light wavelength …
28electromagnetic radiation — Physics. radiation consisting of electromagnetic waves, including radio waves, infrared, visible light, ultraviolet, x rays, and gamma rays. [1950 55] * * * Energy propagated through free space or through a material medium in the form of… …
29ATOME — L’atome est le terme ultime de la division de la matière dans lequel les éléments chimiques conservent leur individualité. C’est la plus petite particule d’un élément qui existe à l’état libre ou combiné. On connaît 89 éléments naturels auxquels… …
30Nuclear poison — A nuclear poison, also called a neutron poison is a substance with a large neutron absorption cross section in applications, such as nuclear reactors, when absorbing neutrons is an undesirable effect. However neutron absorbing materials, also… …
