Nuclear energy release

Chemical reactions, such as the burning of carbon in coal with oxygen, also get energy from rearranging electrostatic forces, but those forces arc much smaller and consequently chemical energies released per atom are much smaller than nuclear energies released per nucleus. 

The vast quantities of nuclear energy released by detonation are distributed... 

Thorium, uranium, and plutonium are well known for their role as the basic fuels (or sources of fuel) for the release of nuclear energy (5). The importance of the remainder of the actinide group Hes at present, for the most part, in the realm of pure research, but a number of practical appHcations are also known (6). The actinides present a storage-life problem in nuclear waste disposal and consideration is being given to separation methods for their recovery prior to disposal (see Waste treati nt, hazardous waste Nuclear reactors, waste managet nt). 

Broeklehurst [37] has written an exhaustive review of the early work (prior to 1977) on fracture in polyerystalline graphite. Mueh of this work foeused on the fraeture behavior of nuclear graphites. In most investigations eonsidered, conventional fracture meehanies tests and analysis were performed for maeroseopie craeks. LEFM provided an adequate eriterion for failure. Additionally, results on work of fraeture, strain energy release rate, and fatigue eraek propagation were reported. 

The process of nuclear fission was discovered more than half a century ago in 1938 by Lise Meitner (1878-1968) and Otto Hahn (1879-1968) in Germany. With the outbreak of World War II a year later, interest focused on the enormous amount of energy released in the process. At Los Alamos, in the mountains of New Mexico, a group of scientists led by J. Robert Oppenheimer (1904-1967) worked feverishly to produce the fission, or atomic, bomb. Many of the members of this group were exiles from Nazi Germany. They were spurred on by the fear that Hitler would obtain the bomb first Their work led to the explosion of the first atomic bomb in the New Mexico desert at 5 30 a.m. on July 16,1945. Less than a month later (August 6,1945), the world learned of this new weapon when another bomb was exploded... 

The two nuclei on the right side are just two of the many possible products of the fission process. Since more than one neutron is released in each process, the fission reaction is a self-propagating, or chain reaction. Neutrons released by one fission event may induce other fissions. When fission reactions are run under controlled conditions in a nuclear reactor, the energy released by... 

Nuclear installations are provided with a pressure explosion suppression and containment shell as an accommodation system against any sudden energy release resulting from an uncontrolled nuclear fission reaction. The internal air pressure is maintained at a level lower than the external atmosphere. 

STRATEGY The nuclear binding energy is the energy released in the formation of the nucleus from its nucleons. Use H atoms instead of protons to account for the masses of the electrons in the He atom produced. Write the nuclear equation for the formation of the nuclide from hydrogen atoms and neutrons, and calculate the difference in masses between the products and the reactants convert the result from a multiple... 

STRATEGY If we know the mass loss, we can find the energy released by using Einstein s equation. Therefore, we must calculate the total mass of the particles on each side of the nuclear equation, take the difference, and substitute the mass difference into Eq. 6. Then we determine the number of nuclei in the sample from N = m(sample)/m(atom) and, finally, multiply the energy released from the fission of one nucleus bv that number to find the energy released by the sample. 

A more constructive approach to nuclear fusion—one that achieves a controlled release of nuclear energy—is to heat a plasma, or ionized gas, by passing an electric current through it. The very fast ions in the plasma are kept away from the walls of the container with magnetic fields. This method of achieving fusion is the subject of intense research and is beginning to show signs of success (Fig. 17.27). 

Nuclear fusion makes use of the energy released when light nuclei fuse together to form heavier nuclei. 

LI 7 Calculate the energy released during a nuclear reaction (Example 17.6). 

Calculate the energy released per gram of starting material in the nuclear reaction represented by each of the following equations. 

A nuclear bomb is a terrifying example of the enormous amount of energy released by nuclear fission. A bomb, however, is not the only way to extract the energy produced by nuclear fission. Instead, nuclear fission can be used... 

Schematic view of a nuclear power plant. The energy source is the core, in which a fission reaction occurs. The rest of the plant is designed to transfer the energy released during fission and convert it into electricity.

---