Word: nitrogen
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...primitive organisms that consumed oxygen as fast as green plants manufactured it. Only by some primeval accident were the greedy organisms buried in sedimentary rock (as the source of crude oil, for example), thus permitting the atmosphere to become enriched to a life-sustaining mix of 20% oxygen, plus nitrogen, argon, carbon dioxide and water vapor. With miraculous precision, the mix was then maintained by plants, animals and bacteria, which used and returned the gases at equal rates. About 70% of the earth's oxygen is thus produced by ocean phytoplankton: passively floating plants. All this modulated temperatures, curbed...
...minimize the amount of oxygen necessary to maintain the two-gas atmosphere (44% oxygen, 56% nitrogen) that the student crew breathes, the simulated spacecraft is equipped with a concentrator that pulls exhaled carbon dioxide out of the air. The carbon dioxide is combined in a catalytic reactor with hydrogen and converted into water and methane. An electrolysis system then decomposes the water into oxygen-for breathing-and hydrogen that is used to feed the catalyti c reactor. Reluctant to waste even the squeal of this chemical pig, McDonnell Doug las engineers are working on spacecraft thrusters that can be powered...
Preventing Disease. From this discovery, Funk correctly theorized that chemical substances which he named vitamines (from the Latin vita for life and amine for chemical compounds containing nitrogen) were capable of preventing deficiency diseases such as scurvy, pellagra and rickets, and indeed were essential to the sustenance of healthy life. The assumption that all vitamins contain nitrogen later proved wrong, and the e was dropped...
High Threshold. The Russians also came to the rescue of U.S. scientists, who had been at a loss to explain preliminary Venus 4 reports that there was no nitrogen in the Venusian atmosphere (nitrogen accounts for 78% of terrestrial air). Backing off slightly, the Soviet scientists explained that the nitrogen-gas analyzer aboard the capsule had a "signal-detection threshold" of 7%; thus it would have been unable to detect smaller percentages...
...avoid shutting down large portions of the city water system when they began installing water meters at every residence, water-department workers in Boulder, Colo., turned to cryogenics. At each house, they poured liquid nitrogen over the inlet pipes, which froze the water inside for 20 minutes and enabled them to install the meter without losing so much as a drip...