《英文msh词典》Ray,Actinic
[入口词] Ray,Actinic
[主题词] Ultraviolet Rays
[英文释义] 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.