conductivity jump
11Sintering — is a method used to create objects from powders. It is based on atomic diffusion. Diffusion occurs in any material above absolute zero but it occurs much faster at higher temperatures. In most sintering processes the powdered material is held in… …
12Valence band — In solids, the valence band is the highest range of electron energies where electrons are normally present at absolute zero. In semiconductors and insulators, there is a band gap above the valence band, followed by a conduction band above that.… …
13Sodium vapor lamp — A sodium vapor lamp is a gas discharge lamp which uses sodium in an excited state to produce light. There are two varieties of such lamps: low pressure and high pressure . Low pressure sodium Low pressure sodium (LPS) lamps, also known as sodium… …
14Quantum wire — In condensed matter physics, a quantum wire is an electrically conducting wire, in which quantum effects are affecting transport properties. Due to the confinement of conduction electrons in the transverse direction of the wire, their transverse… …
15Invention of radio — Great Radio Controversy redirects here. For the album by the band Tesla, see The Great Radio Controversy. Contents 1 Physics of wireless signalling 2 Theory of electromagnetism …
16materials science — the study of the characteristics and uses of various materials, as glass, plastics, and metals. [1960 65] * * * Study of the properties of solid materials and how those properties are determined by the material s composition and structure, both… …
17Nobel Prizes — ▪ 2009 Introduction Prize for Peace The 2008 Nobel Prize for Peace was awarded to Martti Ahtisaari, former president (1994–2000) of Finland, for his work over more than 30 years in settling international disputes, many involving ethnic,… …
18boron group element — ▪ chemical elements Introduction any of the five chemical elements constituting Group 13 (IIIa) of the periodic (periodic law) table (see Figure >). The elements are boron (B), aluminum (Al), gallium (Ga), indium (In), an …
19Fluorescent lamp — A fluorescent lamp or fluorescent tube is a gas discharge lamp that uses electricity to excite mercury vapor. The excited mercury atoms produce short wave ultraviolet light that then causes a phosphor to fluoresce, producing visible light.Unlike… …
20Timeline of electromagnetism — The timeline of electromagnetism, that is the timeline of the human understanding of electromagnetic forces, dates back over two thousand years ago. It lists, within the history of electromagnetism, the associated theories, technology, and events …
