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Luminol and haemoglobin, an example of chemiluminescence UV-photoluminescence in microbiological diagnostics. Luminescence is a spontaneous emission of radiation from an electronically or vibrationally excited species not in thermal equilibrium with its environment.
Fluorescent solutions under UV light. Absorbed photons are rapidly re-emitted under longer electromagnetic wavelengths. Photoluminescence (abbreviated as PL) is light emission from any form of matter after the absorption of photons (electromagnetic radiation). [1]
In phosphors and scintillators, the activator is the element added as dopant to the crystal of the material to create desired type of nonhomogeneities.. In luminescence, only a small fraction of atoms, called emission centers or luminescence centers, emit light.
To separate the brand from Timex, the movements had luxury features associated with a higher-end brand, e.g., sapphire crystals and stainless steel or titanium casework — and used hands treated with super-luminova luminescent pigment for low-light legibility — rather than indiglo technology.
As in many chemical reactions, chemiluminescence starts with the combining of two compounds, say A and B, to give a product C. Unlike most chemical reactions, the product C converts to a further product, which is produced in an electronically excited state often indicated with an asterisk:
Views of a liquid crystal display, both with electroluminescent backlight switched on (top) and switched off (bottom). Electroluminescence (EL) is an optical and electrical phenomenon, in which a material emits light in response to the passage of an electric current or to a strong electric field.
The two most common types of TLDs are calcium fluoride and lithium fluoride, with one or more impurities to produce trap states for energetic electrons.The former is used to record gamma exposure, the latter for gamma and neutron exposure (indirectly, using the Li-6 (n,alpha) nuclear reaction; for this reason, LiF dosimeters may be enriched in lithium-6 to enhance this effect or enriched in ...
The concept of using luminescence dating in archaeological contexts was first suggested in 1953 by Farrington Daniels, Charles A. Boyd, and Donald F. Saunders, who thought the thermoluminescence response of pottery shards could date the last incidence of heating. [15]