Word: carbone
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...dynamite magazine, had devastated the major shaft of the mine that produced all of Rhodesia's coal. On or near the surface, four men were killed instantly. Hundreds of feet below, 426 miners -390 of them black, 36 white-were trapped amid rock and deadly methane and carbon monoxide fumes...
...plans to build a supersonic jet transport last year. Congress was influenced by some persuasive arguments against the plane: it would be extremely costly (an estimated $1.5 billion for development of two prototypes), create window-shattering sonic booms all across the countryside, and possibly even leave enough carbon dioxide in the upper layers of the atmosphere to change the earth's climate. Now Robert T. Jones of NASA'S Ames Research Center, near San Francisco, has suggested a radical new SST design that he claims would overcome most of these objections. It would also...
...organisms capable of photosynthesis-the chemical process by which green plants use the energy of sunlight to convert carbon dioxide and water into food and oxygen-show a marked chemical preference for carbon 12, which is the lighter of the two isotopes. As a result, the carbon in the organic compounds that make up the plants' structure consists largely of carbon 12. What is more, the greater preponderance of that isotope becomes preserved in the earth's geological records when, for example, tiny green sea plants (plankton) die, sink to the ocean bottom, gradually decompose and become part...
...South Africa's Transvaal in an unusual formation of sedimentary rock. Once probably part of a shallow ocean bottom, the stratified rock has now been thrust to the surface and scientists can easily examine it. When Schopfs team compared the relative abundance of the two principal isotopes of carbon in each of the formation's many layers, they made an intriguing discovery. In the newer layers, those formed more recently than 3.3 billion years ago, carbon 12 and carbon 13 appeared in approximately the same ratio as they do in more modern deposits known to contain the fossilized...
Chemical Choice. That sudden change in carbon ratios was highly significant to Schopf and his collaborators, Dorothy Z. Oehler of U.C.L.A. and Keith A. Kvenvolden of NASA'S Ames Research Center. In a recent report in the journal Science, they proceed to explain...