Nuclear reactor

“ Tchassen saw the ship spin out of control as the beam went haywire. The robot plunged into the heart of the station and the earth shook in the catastrophic explosion of the nuclear reactor. The commissary, the communication center, the supply sheds and the row of patrol ships vanished in the rising, mushroom cloud. Concussion threw Tchassen violently to the ground. ”

“ If such a reactor operates for half a year and then explodes and releases its radioactive content into the atmosphere, its radioactivity will be comparable to that of a hydrogen bomb. In one important respect such an accident would be worse than a hydrogen explosion. The nuclear explosive lifts most of its radioactive products to a high altitude and the poisonous activity gets dispersed and diluted before it descends. The activity from a reactor on the other hand will remain close to the ground and might endanger the lives of the people in an area of hundreds of square miles. ”

“ It reminded me instantly of the beer-barrel nuclear reactor, a portable affair, developed by the British physicist Robert Parker. Its purpose dawned on me: This was the trigger of the atomic gun that Chetzisky held at the temples of a planet.
I moved in for a clearer view. As I did I was brought up abruptly by a calm, even voice, its tone of command sharpened in the crisp morning air. "You needn't move any more, gentleman. Just raise your hands."
I looked in the direction of the speaker, as my hands went up. Out of the shadows in front of us emerged a short man with a rifle. Chetzisky! ”

“ Such fuel can be produced through the process of "breeding" within a "fast breeder reactor." The fast breeder reactor differs from the now common light water nuclear reactor in that the neutrons which split atoms in the fuel (thereby releasing new neutrons and heat energy) travel much faster than the neutrons in ordinary reactors. The reactor breeds new fuel through what has aptly been termed "a sort of modern alchemy." ”

“ The reactor is charged with radioactive fission products and some other radioactive substances produced by neutron absorption. Any accident which will allow even a portion of these products to escape into the air will endanger people at a considerable distance in the downwind direction. One reason why reactors can be dangerous is that in protracted operation of the reactor, fission products which have longer lives accumulate. It is precisely these longer-lived products which are more dangerous because they have a better chance to find their way into the human body. ”

“ The most dangerous element in all operations is the human element. We ourselves constitute the greatest safety hazard. This is a situation no different in nuclear technology than in any other kind of technology. What is new in nuclear technology is that a reactor is usually very safe but may become extremely dangerous when something unexpected happens to it. ”

“ There is a huge amount of waste heat from the propulsion system and the nuclear reactor (both fission and fusion reactions) ; The fuel will be stored in large tanks at near-absolute temperatures, and must be shielded from the waste heat of the nuclear reactions. The spacecraft will require highly efficient radiators to dissipate the thermal energy released by the interstellar drive, namely the inductors, particle beams, and fusion reaction. ”

“ Rick looked blank. Steve was talking way over his head. Hartson Brant saw his son's bewilderment and explained: "You've probably heard that the uranium in a reactor is encased in blocks of graphite, which is simply carbon, Rick. It prevents the neutrons from the uranium from simply running wild. Well, heavy water can be used for the same purpose."
"Exactly," Steve said. "So you see, I'm not afraid of the possibility of hydrogen bombs as much as I am of the possibility that somewhere in Asia is a nuclear reactor. ”

“ In the most common type of activation analysis, the neutron bombardment of a sample is performed in a nuclear reactor where the neutrons that strike the target atoms have been slowed down so that they have very little energy of motion. In this case, the usual reaction between the target atoms and a neutron results in the capture of the neutron and this creates a nucleus with an atomic weight of one more unit than it started with. ”

“ Then 2 beta particles are given off so that the thorium-233 becomes first protactinium-233 and then uranium-233.
If a thorium shell surrounds a nuclear reactor, fissionable uranium-233 is formed within it and is easily separated from the thorium. In this way, thorium is also added to the list of earth’s potential nuclear fuels. [4]
If all the uranium and thorium in the earth’s crust (including the thin scattering of those elements through granite, for instance) were available for use, we might get up to 100 times as much energy from it as from all the coal and oil on the planet. ”

“ Then, in March 1941, the element plutonium was isolated, and the plutonium-239 isotope was found to fission as readily as the scarce uranium isotope, uranium-235. The plutonium, produced in a uranium-fueled nuclear reactor, provided the United States with an additional source of material for nuclear weapons (7; 12) .
In the summer of 1941, the British Government published a report written by the Committee for Military Application of Uranium Detonation (MAUD) . This report stated that a nuclear weapon was possible and concluded that its construction should begin immediately. ”

“ The nuclear reactor will have to be ignited, and rechanneled to repower the slowly draining capacitors of the interstellar Drive igniter system, after the spacecraft has fully rotated and stabilized in the proper alignment.
3.2.2.3 Feasibility The entire Interstellar Drive is highly dependent upon enabling technology. Building an actual scale model that is capable of running continuously for 100 years will be a challenge by itself! Barring further significant technological breakthroughs, the collection of fuel will be the most difficult and time consuming portion of the building. ”

“ Nations should therefore look very closely at cost comparisons to obtain the best value when choosing an energy path.
2.2 Health and Environment Risks 47. Very strict codes of safety practice are implemented in nuclear plants so that under officially approved operating conditions, the danger from radiation to reactor personnel and especially to the general public is negligible. However, an accident occurring in a reactor may in certain very rare cases be serious enough to cause an external release of radioactive substances. ”

“ What about the neutrons for the irradiation? Although there isn’t a suitable nuclear reactor [9] in your city, there is one at a university only an hour away by jet. Since it may take a few hours to get the sample to the counter after irradiation, you won’t be able to look for short-lived 22 activation products, i.e., those with half-lives of up to an hour. However, this will exclude only a few elements from detection.
A pulse-height analyzer used for gamma-ray spectrometry. A gamma-ray spectrum is displayed on the television screen. ”

“ The radioactive cloud released from a reactor accident may be more dangerous than a nuclear explosion. Such a cloud will not stop at national boundaries. Some proper form of international responsibility will have to be developed.
What effect the existence of nuclear weapons will have upon the coexistence of nations is a question less understood and less explored than any other affecting our future. Most people turn away from it with a feeling of terror. ”

“ A reactor has been donated by the United States Atomic Energy Commission. With the establishment of this center, we will engage in the production of radioisotopes for the use of agriculture, industry, and medicine. This is a land mark in our scientific progress, as it opens up for our youth the vast field of nuclear science and ultimately harnesses the mightiest industrial power known to man to cancel human poverty from our land. I submit that no project more deserving of full support by Congress than the nuclear center. ”

“ A car was still, in some ways, the result of incremental progression from the horse-drawn carriage. An airplane, and later a rocket, are less along a line of gradual change, but still conceptually close to our own practical experience with flying birds, or with the physics of action and reaction. Nevertheless, a nuclear reactor is well beyond such experiences. The conceptual hierarchy it embodies takes it out of the realm of any previous pragmatic experience. ”

“ The Secretary of State, the Secretary of Defense, the Secretary of Commerce, the Secretary of Energy, and the NASA Administrator shall develop a common technology roadmap through 2030 that describes potential development programs and that coordinates, to the extent practicable, terrestrial-based advanced nuclear reactor and space-based nuclear power and propulsion efforts. Agencies shall remain responsible for funding their respective mission-unique requirements. ”

“ An error in the reactor business could exact a far heavier toll of lives than an error in the testing of H-bombs. We cannot wait to learn by experience; we must forestall accidents.
An especially difficult safety problem is connected with the use of reactors in small countries. ”

“ Blocks of graphite containing uranium metal and uranium oxide were piled up in huge quantities (enriched uranium was not yet available) in order to approach critical size. This took place under the stands of a football stadium at the University of Chicago, with Enrico Fermi (who had come to the United States in 1938) in charge. [1]
136
The large structure was called an “atomic pile” at first because of the blocks of graphite being piled up. The proper name for such a device, and the one that was eventually adopted, was, however, “nuclear reactor”. ”

“ The safety of a reactor, of course, depends to a great extent on the use to which the reactor is put. In general a power station is less likely to give trouble than a moving power source. It is not probable that nuclear locomotives will ever be safe. In nuclear ships more room is available and more room permits more safety measures. But even so the safety of nuclear motors in ships will have to be considered particularly carefully because ships will have accidents in harbors. ”

“ And so, whilst some states still remain nuclear-free, today nuclear reactors supply about 15 per cent of all the electricity generated. Total electricity production worldwide is in turn equivalent to around 15 per cent of global primary energy supply. Roughly one-quarter of all countries worldwide have reactors. ”

“ In principle the nuclear rocket can eventually carry heavier payloads much farther than any chemical rocket. Nevertheless, the technology is so new and the extrapolation from reactors developed now to sizes which would be useful in large rockets is so great that it is not clear how soon they will make an important contribution to the space program. The use of nuclear rockets will raise serious international political problems since the possibility that a reactor could reenter and fall on foreign territory cannot be ignored. ”

“ A working reactor is full of neutrons. In a small fraction of a second these neutrons produce fission and a new generation of neutrons comes into being. In slow reactors which contain lots of light elements like hydrogen or carbon, the neutrons move with speeds little greater than that of sound and a generation may last as long as a millisecond (one thousandth of a second) . In fast reactors which contain almost exclusively heavier elements like uranium or iron, neutrons move with a great speed which is about three per cent of the speed of light. ”

“ A healthy and robust nuclear energy industry is critical to the national security, energy security, and economic prosperity of the United States; (b) The United States should maintain technology supremacy for nuclear research and development, manufacturing proficiency, and security and safety; and (c) The United States Government should bolster national defense and space exploration capabilities and enable private-sector innovation of advanced reactor technologies. ”

“ If an explosion occurs the fission products will be harmlessly confined inside the container. Of course, one must be quite sure that the reactor is of such a type that it cannot produce an explosion great enough to burst the container and what is even more important one should be quite sure that the container is closed except when the reactor is shut down and completely safe. Often it may be best to build the reactor underground. ”

“ This is called a “swimming pool” reactor because the nuclear fuel, built into metal rods, is held in a framework at the bottom of a deep pool of water. The water serves as a shield to protect workers from the radiation and also helps the reactor “go” by slowing down neutrons to make them more likely to interact with the target atoms. “Swimming pool” reactors are frequently used for neutron activation analysis and typically provide neutron fluxes of over 1013 (10 million million) neutrons per square centimeter per second. ”

“ General agreement has developed among most of the key energy community leaders in the cognizant agencies of the Government, in the Congress and in the nuclear community that the breeder reactor is the major long- term solution to the energy supply and related environmental problems. ”

“ Radioactivity is characterized by the kind of particle emitted from the nucleus (our examples, so far, have been of beta and gamma particles) , by the energy possessed by this particle, and by the half-life in which the radioactive decay takes place.
The biological hazard from radioactivity depends on all three of these characteristics. No matter whether the radioactive nuclei are produced in an atomic explosion or in an atomic reactor, some time will in general elapse before a human population can become exposed. ”