Word: hydrogens
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...basic chemistry, he learned, most important, that if he hoped to launch a missile very far, he could never do it with the poor black powder that had long been the stuff of rocketry. Instead, he would need something with real propulsive oomph--a liquid like kerosene or liquid hydrogen, mixed with liquid oxygen to allow combustion to take place in the airless environment of space. Fill a missile with that kind of fuel, and you could retire black powder for good...
...19th century was the century of chemistry, the 20th was the century of physics. The burgeoning science supported such transforming applications as medical imaging, nuclear reactors, atom and hydrogen bombs, radio and television, transistors, computers and lasers. Physical knowledge increased so rapidly after 1900 that theory and experiment soon divided into separate specialties. Enrico Fermi, a supremely self-assured Italian American born in Rome in 1901, was the last great physicist to bridge the gap. His theory of beta decay introduced the last of the four basic forces known in nature (gravity, electromagnetism and, operating within the nucleus...
Fermi died prematurely of stomach cancer in Chicago in 1954. He had argued against U.S. development of the hydrogen bomb when that project was debated in 1949, calling it "a weapon which in practical effect is almost one of genocide." His counsel went unheeded, and the U.S.-Soviet arms race that ensued put the world at mortal risk. But the discovery of how to release nuclear energy, in which he played so crucial a part, had long-term beneficial results: the development of an essentially unlimited new source of energy and the forestalling, perhaps permanently, of world-scale...
...final piece into place. He was in the lab, pondering cardboard replicas of the four bases that, we now know, constitute DNA's alphabet: adenine, thymine, guanine and cytosine, or A, T, G and C. He realized that "an adenine-thymine pair held together by two hydrogen bonds was identical in shape to a guanine-cytosine pair." These pairs of bases could thus serve as the rungs on the twisting ladder...
Skeptics--"pistonheads," Ballard calls them--say the company is decades away from making fuel-cell cars affordable, if it ever can. But some of the largest automakers are betting on a hydrogen future. DaimlerChrysler and Ford have paid $750 million for 35% of Ballard Power Systems, vowing to market fuel-cell cars within five years. Since hydrogen is difficult to store, current research focuses on fueling the cars with methanol, from which hydrogen would be extracted on board. That process would produce pollution, but not nearly as much as conventional engines give...