Light Ultraviolet entries

When exposed to ultraviolet light, dienes 411 and 412 undergo intramolecular [2+2] cycloaddition. The latter reaction provides a particularly convenient synthetic entry to [3.3.2]propellane from a readily available starting material... 

Windows must function properly. They should be of weather proof construction, ultraviolet-ray (uv) filtered, and draped to prevent the entry of unnecessary heat, dust, and light. Light bulbs and fixtures should be properly positioned and lights turned on for as few hours as possible to reduce emission of heat and light. 

Conditions for Photochemical Water Cleavage. Aqueous Pt/Ti02 (Anatase) Dispersions under Ultraviolet Light As in Entries 24 and 25 (Refs. 244, 245) photocatalyst dispersions studied. 253... 

Chronic exposure to PAHs can produce a variety of effects. Exposure to the eyes can result in irritation and photosensitivity. Dermal exposure can result in erythema, burns, and coal tar warts (precancerous lesions enhanced by ultraviolet light exposure). Inhalation exposure may cause irritation to the respiratory tract accompanied by cough and bronchitis. Oral exposure may produce a thickening and/or whitening of the oral mucous membranes. In addition to the local effects at the site of entry, systemic toxicity may occur, which could result in hepatic or renal effects. Some PAH compounds have been noted to cause hematological effects (anemia, leukopenia, and pancytopenia) in animals and suppression of selective components of the immune system. 

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