Word: ratings
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Dates: during 1950-1959
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...heat generated strikes back to the fuel, gasifies more of it, and so keeps the flame burning. When this characteristic was discovered by Dr. Martin Summerfield of Princeton, the next step was to look for something that would control the gas mixture. A faster mixing would increase the burning rate, while slower mixing would decrease it. If the control were precise enough, scientists would then have what amounts to a throttle for solid fuels...
When they reach the hardware stage, Acoustica's engineers will build an experimental rocket engine with a cylindrical cavity running through the mass of fuel (see diagram). A "grain"' of this shape is simple and strong, but if left alone it burns at an uneven rate: as the fuel is consumed, the cavity gets bigger and exposes more surface to the heat. Since the amount of hot gas generated is proportional to the area of burning fuel, the gas pressure keeps rising until just before burnout. The effect is that solid-fuel rockets of this type must have...
Acoustica's idea is to control the fuel by blowing high-pressure gas through a heat-resistant whistle at the forward end of the cylinder's cavity. While the cavity is still small, the whistle will screech at full power, increasing the burning rate of the fuel. As the cavity grows bigger, a valve will reduce the amount of gas passing through the whistle. The volume of sound will decrease, and so will the fuel's burning rate. If the valve is manipulated efficiently by some pressure-sensing instrument, it will keep the hot gas inside...
...Bioluminescence) that light emitted by certain organisms (fireflies, squid) indicates their growth and functioning; of a heart attack; in Woods Hole, Mass. In 1931, in collaboration with New York Banker Alfred Lee Loomis, Harvey invented the centrifuge microscope, which makes cell division observable by whirling the cells at a rate of 20,000 revolutions a minute...
...fourth quarter of 1959, the U.S. economy will pass a long-awaited milestone far ahead of schedule. Americans by then will be producing, earning, spending and investing at the rate of $500 billion yearly, raising the U.S. to the level of a half-trillion-dollar economy. For each of the nation's 45 million families, the breakthrough will represent some $11,000 worth of goods and services produced by U.S. factories, farms, mines, government and service industries. The total will be many billions greater than the combined gross national products of the Soviet Union, Great Britain, West Germany...