Word: physicist
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Last week the vulnerability of the ozone layer was emphasized by two startling reports on the long-range effects of the propellant gases used in aerosol sprays. Writing in Science, University of Michigan Physicist Ralph Cicerone notes that spray-can gases, mostly chlorine compounds such as Freon, are highly stable under ordinary circumstances. Thus they are building up in the lower atmosphere and gradually rising toward the ozone layer. At that altitude, ultraviolet radiation breaks down Freon and the other chlorine-based gases, causing the release of chlorine atoms. They in turn react with ozone, converting it into ordinary oxygen...
...synthesis of element No. 106 was announced last week by a Berkeley team led by Physicist Albert Ghiorso and Chemist Glenn Seaborg, the former Atomic Energy Commission chairman who won a Nobel Prize for synthesizing element No. 94 (plutonium). The Berkeley scientists used a newly beefed-up particle accelerator called Super-HILAC (for heavy ion linear accelerator) to send nuclei of oxygen atoms barreling into another artificial element, californium. As occasional collisions occurred between the oxygen and californium nuclei, they fused and formed the heavier nucleus of element 106-but not for long. Like most artificial elements...
Shaky Ground. The Russians, led by Physicist Georgy N. Flerov, last June claimed a similar achievement using another technique: firing nuclei of chromium into lead. That produced a slightly different isotope of element 106 with an even shorter half-life of less than one-hundredth of a second. The Berkeley group was highly skeptical. Said Ghiorso: "The proof they presented is marginal. I think they are on shaky ground...
...Applied Chemistry to settle the issue. The union still has not determined who first made elements 104 and 105, for which each side has filed claims and names. The Russians are calling 104 "kurchatovium" (after their A-bomb pioneer, Igor Kurchatov) and 105 "niels bohrium" (for the famed Danish physicist). Americans have dubbed 104 "rutherfordium" (after the English scientist Ernest Rutherford) and 105 "hahnian" (for German Chemist Otto Hahn, who discovered nuclear fission...
...scientist at Canada's Ontario Research Foundation has found a convenient way to overcome the microscope's handicap; Physicist Eric J. Chatfield has devised an adapter system that enables the electron-microscope user to get three-dimensional images. His optical stereo, which he developed at a cost of only $25,000-less than the price of a typical electron-microscope-operates on an ingenious yet simple principle reminiscent of Hollywood's experiments with 3-D movies in the 1950s...