Word: nuclei
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Dates: during 1960-1969
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General Destruction. The still-theoretical neutron bomb will use a "pure-fusion" reaction, a third generation in nuclear explosions. In old-fashioned fission (Abomb) explosions, nuclei of uranium or plutonium split roughly in half, and the big, heavy fragments are shoved apart by powerful electrical forces. Almost at once they collide with other nuclei, with other materials in the bomb and with the surrounding air. The collisions slow the nuclei down and turn their original energy into heat. The result is a high-temperature fireball that sears its surroundings with heat radiation and expands so violently that it generates...
...Torbjorn Sikkeland, Almon E. Larsh and Robert M. Latimer), by coating thin nickel foil with a circular film of artificial californium (element 98) only one-tenth of an inch in diameter. Placed in a container filled with helium gas, this tiny target was bombarded by a beam of boron nuclei from the lab's heavy-ion linear accelerator. Most of the boron bullets missed, but a few scored a bull's-eye on californium nuclei. Atoms formed by the combination of californium and boron bounced off the nickel foil, were slowed by collision with helium atoms and were...
Mason's next step was to cool droplets containing microscopic nuclei made of substances that are common in powder-fine dust blown up from the earth's surface. A few kinds proved almost as effective as silver iodide smoke, but most required very low temperatures before they could turn cold clouds into snow...
Trained Dust. In further experiments, Mason showed that some kinds of common natural dust can be "trained" to collect ice. Particles of kaolinite (common in clays) do not act as ice-forming nuclei above 16° F., which is colder than the tops of many clouds. But when kaolinite particles have once had ice crystals on them, and when this ice has evaporated, they are able to form fresh crystals in clouds no colder than...
...nuclear fusion into helium and heavier elements. With the hydrogen gone, the star contracts. As its mass concentrates into a smaller volume, its gravitational field increases in power, eventually growing strong enough to compress the material near the star's center into "degenerate" matter whose electrons and nuclei have been pushed close together...