Word: nucleus
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...routed underneath the basin). Elsewhere, plans are being developed for underground parking for 25,000 cars, which at present clog the Mall and surround the Lincoln Memorial with a carbon-monoxide sea at rush hour. Funds are also now available for the Pershing Monument, which will serve as the nucleus for a new National Center at the White House end of Pennsylvania Avenue. And as of last week, most of the go ahead signals had been given for three major structures that Owings believes will give impressive body and substance to the emerging new Washington...
Last year, Walker and another colleague discovered what may prove to be an even more sensitive dating method-the measurement of alpha-particle tracks. Uranium nuclei frequently emit an alpha particle. As the particle is expelled, the nucleus recoils. Walker reasoned that "recoil tracks would be there, so I looked for them." He discovered that observable recoil tracks occurred 4,000 times more than fission tracks. When acid etching and track counting are perfected for alpha particles, the method should provide a means of dating infinitesimally small objects and those too young to have accumulated measurable amounts of fission tracks...
Dating the Moon. Walker's methods have already produced important discoveries. By analyzing fission tracks, Russian scientists recently identified the 104th chemical element, named Khurchatorium, arid U.S. research scientists spotted the phenomenon of triple fission-the splitting of a nucleus into three roughly equal parts. General Electric scientists have irradiated thin strips of plastic, etched the fission tracks with acid, and produced a material of great potential medical significance-a sensitive sieve that duplicates the filtering capacity of human membranes...
...Geneticist Hannes Laven of the Johannes Gutenberg University in Mainz discovered that common mosquitoes from Paris that were mated with members of the same species from Hamburg would not produce offspring. The reason for this sterility, he determined, was a difference in the cytoplasm (the protoplasm surrounding the cell nucleus) between the Paris and Hamburg strains of mosquitoes. Because of this difference, the egg cells of the females of one strain could not accept the sperm cells from males of the other strain, causing the female to lay infertile eggs. This Franco-German incompatibility was not unique. In succeeding years...
...celebrate the British North America Act of 1867, which united four colonies into the nucleus of modern Canada, the whole nation is caught up in a yearlong birthday party, whose centerpiece is Expo 67, the admirable international exhibition that opened in Montreal last week (see MODERN LIVING). Expo's space-age shapes will once and for all blot out the world's clichés about Canada: Mounties bracing blizzards, Eskimos crouched over a kodlik swapping wives, bluff Quebeckers doffing berets to passing priests. Expo 67 spectacularly dramatizes Canada's achievements. If there remains an undercurrent...