Luminous phenomena

This has led to such cases in the history of chemistry that spectroscopic signals have been unidentified till newly discovered elements was found (e.g. rubidium, caesium, indium, helium, rhenium) or new species (highly ionized atoms, e.g. in northern lights [aura borealis], luminous phenomena in cosmic space and sun aura, such as nebulium , coronium , geocoronium , asterium , which was characterized at first to be new elements see Bowen [1927] Grotrian [1928] Rabinowitsch [1928]). 

Luminous Phenomena. See Detonation (and Explosion) Luminosity (Luminescence) Produced on, in Encycl 4 (1969), D425-L to D434-L Flash and Flame in Encycl 6 (1974), F74-R to F75-L, and Fluorescence, Luminescence and Phosphorescence, F124-R to F125-L Addl d Refs 1) A. Michel-Ldvy H. Muraour, CR 206, 1566-8 (1938) CA 32, 5629 (1938) (Luminosity of expls) 2) H. Muraour, A. Michel-Levy J. Rouvillois, CR 208,... 

The luminous phenomena in these ozonizers occur in the shape of more or less wide, colored bands of light, mostly in a horizontal and radial direction. Non-luminous vapors either remain wholly dark or become,—this is oftener the case,— interspersed with green-colored sparks. The sparks very rapidly decompose the vapors, precipitating carbonaceous substances the luminosity itself, on the contrary, produces only extremely trifling changes in the substances. 

Concerning the luminous phenomena, near the cathode there is a light region, the cathode glow. The glow arises from the neutralization of ions of the gas dischaige and from the decaying of excited states. 

The luminous phenomena caused by solid-state oxidation are called glowing. Glowing combustion exists when high-surface solids (such as powders or expanded... 

Leucht-erscheinung, /. luminous phenomenon, -faden, m. luminous filament glow column light streamer. 

The interaction of IP3 with its receptor involves complex and poorly understood regulatory interactions among the receptor, IP3 and Ca2+ - the latter apparently exerting influence from both the cytoplasmic and luminal aspects of the receptor. Ca2+ in the lumen of the ER appears to sensitize the receptor to IP3. On the cytoplasmic surface, low concentrations of Ca2+ sensitize while higher concentrations are inhibitory. These actions may contribute to the all-or-none oscillatory behavior of [Ca2+] signals seen in some cell types. This phenomenon will be discussed in more detail below. 

A scenario imagined by Zwicky in 1938 was for a long time the only explanation of the phenomenon. According to this view, a supernova marks the transformation of a normal star into a neutron star, drawing its energy from gravitational collapse. This led astronomers to think that the death of a star was the transition from luminous perfection to a kind of dark perfection. 

Bioluminescence is the production of light by living systems. The best-known example of this phenomenon is the characteristic glow of the firefly, but other luminous species include bacteria, fungi and other animals such as jellyfish, scale-worms, deep-sea squid, prawn and fish. In animals bioluminescence is used as a diversionary tactic when disturbed, to attract prey and of course as a mating signal during courtship. 

The phenomenon of cooling flows , described for luminous clusters, also applies to other systems with gaseous atmospheres. In particular, galaxy groups, the poorer cousins of rich clusters, (e.g., Helsdon et al. 2001) and individual early type galaxies with their luminous, X-ray coronae (Forman, Jones Tucker 1985) also frequently have short gas cooling times at their centers (Thomas et al. 1986). 

The cool flame phenomenon seems to be closely tied to the formation of aldehydes and peroxides in oxidation systems. In Fig. XIV. 10 is shown a typical example of the explosion limits for a hydrocarbon-oxygen mixture. The explosion region, except for a region of positive slope, resembles the limit curve for a thermal explosion. The transition between slow combustion and explosion is characterized by an intense luminous blue flame which appears after a short induction period and is followed by explosion. The induction periods are not more than a few seconds. 

Electroluminescence (EL) is the phenomenon by which electrical energy is converted into luminous energy by the recombination of electrons and holes in the emissive material [8], The basic structure of an OLED consists of a thin film of organic material sandwiched between two electrodes, an anode of high-work-function material such as indium tin oxide (ITO) on a glass substrate, and a cathode of a low-work-function metal such as calcium (Ca), magnesium (Mg), or aluminum (Al) or an alloy such as Mg Ag. 

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