\ˌʊltɹɐvˈa͡ɪ͡ələt ɹˈe͡ɪz], \ˌʊltɹɐvˈaɪələt ɹˈeɪz], \ˌʊ_l_t_ɹ_ɐ_v_ˈaɪə_l_ə_t ɹ_ˈeɪ_z]\
Definitions of ULTRAVIOLET RAYS
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That portion of the electromagnetic spectrum immediately below the visible range and extending into the x-ray frequencies. The longer wavelengths (near-UV or biotic or vital rays) are necessary for the endogenous synthesis of vitamin D and are also called antirachitic rays; the shorter, ionizing wavelengths (far-UV or abiotic or extravital rays) are viricidal, bactericidal, mutagenic, and carcinogenic and are used as disinfectants.
By DataStellar Co., Ltd
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