6/28/2023 0 Comments Nuclear fission energyFermi led a team that in 1942 achieved the first nuclear chain reaction, under a stadium at the University of Chicago. The idea of nuclear power began in the 1930s, when physicist Enrico Fermi first showed that neutrons could split atoms. Other types of nuclear power reactors include gas-cooled reactors, which use carbon dioxide as the cooling agent and are used in the U.K., and fast neutron reactors, which are cooled by liquid sodium. most nuclear reactors are either boiling water reactors, in which the water is heated to the boiling point to release steam, or pressurized water reactors, in which the pressurized water does not boil but funnels heat to a secondary water supply for steam generation. A byproduct of nuclear reactions, plutonium, can also be used as nuclear fuel. That collision-called nuclear fission-releases more neutrons that react with more atoms, creating a chain reaction. In a nuclear reactor, neutrons-subatomic particles that have no electric charge-collide with atoms, causing them to split. Mined uranium is processed into U-235, an enriched version used as fuel in nuclear reactors because its atoms can be split apart easily. The most common fuel for nuclear power is uranium, an abundant metal found throughout the world. The countries generating the most nuclear power are, in order, the United States, France, China, Russia, and South Korea. The resulting steam spins a turbine connected to a generator, producing electricity.Ībout 450 nuclear reactors provide about 11 percent of the world's electricity. This process, nuclear fission, generates heat that is directed to a cooling agent-usually water. Such issues mean that nuclear energy is not as popular as more conventional methods of obtaining energy, such as the use of fossil fuels.Nuclear power is generated by splitting atoms to release the energy held at the core, or nucleus, of those atoms. At the same time, people often fear the dangers that could come with nuclear plants and do not want them in their area. However, the process creates a significant amount of nuclear waste that can be hazardous to both people and the environment. More commonly, fission is used to generate energy within a nuclear power plant. The knowledge itself is not overly complex, but the materials that fund the process are significantly more difficult to obtain. Since then, nuclear research has been considered extremely sensitive. Two subsequent atomic weapons were used as part of a military strike on the cities of Hiroshima and Nagasaki in Japan. Known as the "Manhattan Project," the top-secret endeavor resulted in the formation of the first atomic bomb in July 1945. In 1943, the Army Corp of Engineers took over the research for making a nuclear weapon. Roosevelt allocated money toward American research, and in 1941, the Office of Scientific Research and Development was formed with the aim of applying the research toward national defense. President Franklin Roosevelt at the start of World War II, drafted by Hungarian physicist Leo Szilard and signed by Albert Einstein, noted that such research could be used to create a bomb of epic proportions, and addressed the idea that the Germans could feasibly deliver such a weapon to the American doorstep. In an intellectual chain reaction, scientists began to realize the possibilities incumbent in the new discovery. A single impact could jumpstart a chain reaction, driving the release of still more energy. Ultimately, other physicists realized that each newly freed neutron could go on to cause two separate reactions, each of which could cause at least two more. Working on the problem, she established that fission yielded a minimum of two neutrons for each neutron that sparked a collision. Previous efforts by physicists had resulted in only very small slivers being cut off of an atom, so the pair was puzzled by the unexpected results.Īustrian-born physicist Lise Meitner, who had fled to Sweden following Hitler's invasion of her country, realized that the split had also released energy. In a surprising twist, they wound up splitting the atom into the elements of barium and krypton, both significantly smaller than the uranium that the pair started out with. In 1938, German physicists Otto Hahn and Fritz Strassman bombarded a uranium atom with neutrons in an attempt to make heavy elements. Radioactive fission, where the center of a heavy element spontaneously emits a charged particle as it breaks down into a smaller nucleus, does not occur often, and happens only with the heavier elements.įission is different from the process of fusion, when two nuclei join together rather than split apart.
0 Comments
Leave a Reply. |