| Summary: | This special volume consists of eight chapters consisting of seven Review papers and one Research paper. "Luminescence Phenomena: An Introduction" is the first Chapter contributed by KVR Murthy and HS Virk. It explains the basic phenomenon of Luminescence: "Luminescence is "cold light", light from other sources of energy which can take place at normal and lower temperatures. The word luminescence was first used by a German physicist, Eilhardt Wiedemann, in 1888. In Latin 'Lumen' means 'light'. The materials exhibiting this phenomenon are known as 'Luminescent materials' or 'Phosphors' meaning 'light bearer' in Greek. Luminescence is basically a phenomenon of emission of light from an insulator followed by prior absorption of energy from ionizing radiations like, X-rays, alpha, beta and gamma radiations. The energy lifts the atoms of the material into an excited state, and then, because excited states are unstable, the material undergoes another transition, back to its unexcited ground state, and the absorbed energy is liberated in the form of either light or heat or both. The excitation involves only the outermost electrons orbiting around the nuclei of the atoms. Luminescence efficiency depends on the degree of transformation of excitation energy into light, and there are relatively few materials that have sufficient luminescence efficiency to be of practical value". Keyword: Luminescent phenomena; Thermoluminescence; Elastico-Mechanoluminescence Seven review papers and one research report explore the current understanding of both natural and artificial luminescence. After an introduction, they cover thermoluminescence and its applications, recent advances and opportunities in thermoluminescent dosimeter (TLD) materials, luminescence dating: the basic approach to geochronology, the elastico-mechanoluminescence of thermoluminescent crystals, thermoluminescent phosphors for radiation dosimetry, using the optically stimulated luminescence (OSL) and thermoluminescence (TL) of electronic components in portable devices for retrospective accident dosimetry, and optical and morphological studies of doped core shell ZnS:Cu/ZnS nanoparticles. -- Biochemistry
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