Kampers pro nuclear

Nuclear power stations are not atomic bombs waiting to go off, and are not prone to "meltdowns".

Nuclear power costs about the same as coal, so it's not expensive to make. Does not produce smoke or carbon dioxide, so it does not contribute to the greenhouse effect. Produces huge amounts of energy from small amounts of fuel. Produces small amounts of waste. Nuclear power is reliable.

Nuclear

New Nuclear Power Technologies Introduction: There are many new waste disposal technologies which could prove to be somewhat of a solution to the problem of nuclear waste. Reprocessing, The Missing Step: Although not a new technology, reprocessing can be part of the solution to nuclear waste. When nuclear power was first developed, it was assumed that spent nuclear fuel would go through a process called reprocessing. In reprocessing, one of the major transuranic wastes, 239Pu, is extracted from the spent fuel rods. This 239Pu (plutonium-239) is fissile and can be reused in power plants. The advantages of this process are somewhat obvious: The volume of waste is lessened and more fuel is created for nuclear reactors. However, as with all things, politics can get in the way. In the US plutonium reprocessing was banned because the recovered 239Pu is weapons grade material. If, after reprocessing, the fuel is stolen, it could be used by anyone to construct a nuclear weapon. As of a few years ago, the ban against reprocessing in the US was lifted, but there are still no operating reprocessing plants in the US because of the heavy regulations and the anti-nuclear sentiment of the general public. There are a few countries which do reprocessing, however. France, for instance, regularly reprocesses its spent fuel. High Temperature Breeder Reactors: Many of us are familiar from television (and hopefully not from real life experience) of the bar-room game in which a very large man holds a mug of beer on top of his head and challenges people to punch him. If his opponent punches him hard enough, the beer falls off and spills all over the man holding it. The harder the punch, the better chance that the beer will fall off and the puncher will win. Also, the bigger the man is who is getting punched, the harder the punch must be to knock the beer down. You might be wondering why we are talking about a bar-room game. Think of the guy holding the beer as an atom and the guy punching as a neutron. The transuranic elements are bigger than uranium and generally don't fission (get their beer knocked off) in a regular reactor. The neutrons aren't excited enough (don't punch hard enough) to induce fission in them. However, if they are placed in a high-temperature reactor in which the neutrons are much more excited (and carry more punch), there is a much better chance that they will fission. In a reactor being developed by Argonne National Laboratory in the US, almost 100% of the transuranic nuclear wastes produced through neutron capture can be caused to fission. Generally, the fission products created have shorter half-lives and are not as dangerous. This reactor, dubbed EBR-II, uses liquid sodium as a coolant, which means that the internal reactor temperature is much, much hotter than that of a normal PWR reactor, which uses water as a coolant. Another advantage of EBR-II is that its fuel is not weapons grade quality. When the transuranic wastes are separated from the other wastes in the spent fuel rods, the resultant mix of isotopes can not be used in a bomb. Thus, the mix can be used as fuel for EBR-II without a chance of it getting stolen by a terrorist group for use in an explosive device. Breeder reactors "breed" fuel. That is, they are designed to create 239Pu from 238U through neutron capture. This "waste" can then be used as fuel.

Since their introduction in 1945, nuclear explosives have been the most feared of the weapons of mass destruction, in part because of their ability to cause enormous instantaneous devastation and of the persistent effects of the radiation they emit, unseen and undetectable by unaided human senses. The Manhattan Project cost the United States $2 billion in 1945 spending power and required the combined efforts of a continent-spanning industrial enterprise and a pool of scientists, many of whom had already been awarded the Nobel Prize and many more who would go on to become Nobel Laureates. This array of talent was needed in 1942 if there were to be any hope of completing a weapon during the Second World War. Because nuclear fission was discovered in Germany, which remained the home of many brilliant scientists, the United States perceived itself to be in a race to build an atomic bomb. When the Manhattan Project began far less than a microgram of plutonium had been made throughout the world, and plutonium chemistry could only be guessed at; the numbers of neutrons released on average in U-235 and Pu-239 fissions were unknown; the fission cross sections (probabilities that an interaction would occur) were equally unknown, as was the neutron absorption cross section of carbon. experiment. Although talented people are essential to the success of any nuclear weapons program, the fundamental physics, chemistry, and engineering involved are widely under-stood; no basic research is required to construct a nuclear weapon. Therefore, a nuclear weapons project begun in 1996 does not require the brilliant scientists who were needed for the Manhattan Project.

The JCO plant needed to mix some high-purity enriched uranium oxide with nitric acid to form uranyl nitrate for shipping. The dissolving and mixing began on September 28, 1999. On the morning of September 30, 1999, three technicians, Hisashi Ouchi, Masato Shinohara, and Yutaka Yokokawa, were running fuel through the last steps of the conversion process. To speed up the process, they mixed the oxide and nitric acid in 10-liter stainless steel buckets rather than in the dissolving tank. In doing so, they followed the practice that JCO had written into its operating manual but which had not received STA approval. For convenience, they added the bucket contents directly to the 45-cm-diameter, water-jacketed precipitation tank rather than to the buffer tank. That was a crucial error because the tall, narrow geometry of the buffer tank was designed to preclude the onset of criticality. In filling the precipitation tank, the crew added seven buckets, amounting to a total of about 16 kg (35 lbs of enriched uranium, or roughly seven times more uranium than permitted under the STA license. The three technicians were working in a small processing bay. Masato Shinohara stood on a platform and was pouring the uranyl nitrate solution into the precipitation tank while Hisashi Ouchi held a glass funnel in an inlet at the top of the tank. The third technician, Yutaka Yokokawa, was seated at a desk approximately 4 meters (13 feet) away from the precipitation tank. At approximately 10:35 a.m. the technicians added the seventh bucket and saw a blue flash. The two technicians near the vessel began to experience pain, waves of nausea, some difficulty in breathing, and problems with mobility and coherence. The gamma radiation alarms activated immediately. The blue flash that they had seen was a result of the Cherenkov radiation that is emitted when nuclear fission takes place and ionizes air. The addition of the seventh bucket had caused a self-sustaining chain reaction. The mixture, in other words, had gone critical. Mixing in the precipitation tank caused the fissile uranium species to disperse so that the reaction fizzled out. However, the critical mass later reassembled, initiating another chain reaction that released more neutrons and gamma radiation. This cycle was repeated several times over many hours.

Nuclear medicine

LONG-TERM PERFORMANCE ISSUES OF NUCLEAR-WASTE PACKAGE MATERIALS The longevity of manufactured materials in the repository environment over such long periods of time is subject to significant uncertainty. At the same time, the prediction of material performance is essential in the development and use of waste packages (waste forms and waste containers). In the absence of a good mechanistic understanding of a material’s performance and data that span a wide range of the expected performance and physicochemical conditions, extremely conservative assumptions need to be considered. Many of the performance predictions rely on data collected over a relatively limited range of test conditions; thus, extrapolation of these data requires good mechanistic understanding.16,26 Without proper data support, any benefits that the waste forms or container might provide could be ignored; hence, it is highly desirable to improve the predictability of the materials performance. This also requires demonstration of quality control of the product. Various technical issues must be addressed in the assessment of the long-term performance of the waste package in a geologic repository.27,28 As all components of a waste package may be altered in time within the repository environment, the environment for a waste package (both internal and external) must be well characterized. A demonstrated understanding of factors that might affect long-term service behavior is required for the characterization of materials for the waste-package components. These factors include variations in characteristics such as chemical composition, stress state, microstructure, fabrication or production history, and thermodynamic phase equilibria. Various interactions may be expected from gaseous or aqueous media that are in contact with the materials of the waste package. For metallic containers, various forms of corrosion that result from interactions with water and oxygen are important, as are the effects of hydrogen, which may result from radiolysis of water and vapor or galvanic coupling with borehole liner or container support structures. The environment may produce hydrostatic or lithostatic pressure, which may alter the stress state in waste-package components. Radiation will change the environment and create species with the potential for accelerated degradation of the waste-package components. Microbial species, if they are present in significant quantities, have the potential for interactions with the waste-package materials.29 The service life of the waste package must be determined based on the consideration of these interactions between the environment and the waste-package components, including joints, seals, and welds. For details on the experimental programs specific to Yucca Mountain, refer to Reference 21.