Word: ultraviolet
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...report, published in the New England Journal of Medicine, indicates that most patients face no additional risk from the new technique, which uses a combination of ultraviolet light and special drugs...
...Space Telescope, a 2.4 m (94 in.) mirror scheduled to be placed in orbit by the space shuttle in the early 1980s. Flying above the obscuring atmosphere, this observatory should pick up a variety of celestial phenomena, including infrared and ultraviolet radiation, and reveal hidden structural details of galaxies that may harbor black holes...
...peasant growers of the Sierra Madre soon developed a new strategy to combat the herbicides. Paraquat kills in the sun. Its chemistry requires about three days of ultraviolet rays in order to destroy the plants on which it has been sprayed. To save the marijuana, peasants began to rush out and harvest the plants minutes after the helicopters were gone; they put their plants in bags to shield them from the sun. Even though they had been sprayed, the leaves of plants so shielded did not yellow. The plants appeared normal, so the peasants could sell them as if they...
...ozone layer acts as a shield for the earth, blocking harmful amounts of ultraviolet radiation. McElroy was among the first to postulate that man-made propellants, such as freon in aerosal sprays, are a primary danger to the ozone layer...
...about 2,000° F.) oxygen-containing gas or steam. In effect, the wafers are rusted-covered by a thin, electrically insulating layer of silicon dioxide that prevents short-circuiting. Then the wafers are coated with still another substance: the resist, a photographic-type emulsion sensitive only to ultraviolet (UV) light. (To prevent accidental exposure, clean rooms are generally bathed in UV-less yellow light.) Next, a tiny mask, scaled down photographically from a large drawing and imprinted with hundreds of identical patterns of one layer of the chip's circuitry, is placed over the wafer. Exposed...