Nuclear fusion weapons

This natural inventory was dwarfed by the production of tritium by the atmospheric testing of nuclear fusion weapons during the 1950s and early 1960s. During this period, several hundred kilograms of tritium were released, largely late in the test series, and primarily in the Northern Hemisphere. The... 

Extreme Applications of Barometry. The basic origins of pressure can be used to explain the pressure due to radiation as the momentum flux of photons. At Earth s orbit around the Sun, the solar intensity of 1.38 kilowatts per square meter causes a radiation pressure of roughly 4.56 micropascals. Solar sails have been proposed for long-duration missions in space, driven by this pressure. Close to the center of the Earth, the pressure reaches 3.2 to 3.4 million bars. Inside the Sun, pressure as high as 250 billion bars is expected, while the explosion of a nuclear-fusion weapon may produce a quarter of that. Metallic solid hydrogen is projected to form at pressures of 250,000 to 500,000 bars. 

Helium-3 [14762-55-1], He, has been known as a stable isotope since the middle 1930s and it was suspected that its properties were markedly different from the common isotope, helium-4. The development of nuclear fusion devices in the 1950s yielded workable quantities of pure helium-3 as a decay product from the large tritium inventory implicit in maintaining an arsenal of fusion weapons (see Deuterium AND TRITIUM) Helium-3 is one of the very few stable materials where the only practical source is nuclear transmutation. The chronology of the isolation of the other stable isotopes of the hehum-group gases has been summarized (4). 

It IS often stated that unclear fusion tvill produce no radioactive hazard, but this is not correct. The most likely fuels for a fusion reactor would be deuterium and radioactive tritium, which arc isotopes of hydrogen. Tritium is a gas, and in the event of a leak it could easily be released into the surrounding environment. The fusion of deuterium and tritium produces neutrons, which would also make the reactor building itself somewhat radioactive. However, the radioactivity produced in a fusion reactor would be much shorter-lived than that from a fission reactor. Although the thermonuclear weapons (that use nuclear fusion), first developed in the 1950s provided the impetus for tremendous worldwide research into nuclear fusion, the science and technology required to control a fusion reaction and develop a commercial fusion reactor are probably still decades away. 

Nuclear weapons are broadly divided into two classes -Fission weapons and fusion weapons depending on the dominant source of the weapon s energy. 

Nuclear weapons which usually use nuclear fusion, have far greater yields than weapons, which use only fission, as fusion releases more energy per kilogram and can also be used as a source of fast neutrons to cause fission in depleted uranium. 

Further, the light weight of the elements used in fusion makes it possible to build extremely high yield weapons which are still portable enough to deliver. Compared with large fission weapons, fusion weapons are cheaper and much less at risk of accidental nuclear explosion. 

The distinction between these two types of weapons is blurred because they are combined in almost all advanced modern weapons. For example, a smaller fission bomb is first used to create necessary conditions of high temperature and pressure which are required for fusion. Similarly, fusion elements may also be present in the core of fission devices as well because they generate additional neutrons which increase efficiency of the fission reaction. Further, most of the fusion weapons derive substantial portion of their energy from a final stage of fissioning which is facilitated by the fusion reactions. The simplest nuclear weapons are pure fission bombs. They were the first type of nuclear weapons built during the American Manhattan Project and are considered as a building block for all advanced nuclear weapons. 

Atomic (or Nuclear) Bomb. A weapon invented during WWII and developed in the United States as a joint effort with the British and Canadian governments. It utilizes for its destructive effect the energy of an Atomic or Nuclear Explosion (qv). Since atomic explosions are of two types, fission and fusion, atomic bombs are of. corresponding types. However, it has been necessary to first initiate an atomic explosion with a nuclear fission reaction in order to bring about the conditions under which a nuclear fusion(thermonuclear) reaction can occur. 

Explosions can be used for constructive purposes, such as mining and road building for entertainment, such as fireworks or for destructive purposes, such as military weapons and terrorist bombs. They may be either deliberate or accidental. Explosive materials must always be handled with extreme care to prevent accidents. Such caution must be exercised with not only industrial explosives, but also commonly encountered materials such as fireworks, laboratory and industrial chemicals, and flammable gases, see also Fire, Fuels, Power Plants Fireworks Kinetics Nuclear Fission Nuclear Fusion Thermodynamics. 

Deuterium (2D) and tritium (3T) are heavier isotopes of hydrogen. The former is stable and makes up about 0.015 per cent of all normal hydrogen. Its physical and chemical properties are slightly different from those of the light isotope Tl For example, in the electrolysis of water H is evolved faster and this allows fairly pure D2 to be prepared. Tritium is a radioactive b-emitter with a half-life of 12.35 years, and is made when some elements are bombarded with neutrons. Both isotopes are used for research purposes. They also undergo very exothermic nuclear fusion reactions, which form the basis for thermonuclear weapons (hydrogen bombs) and could possibly be used as a future energy source. 

As research on fusion weapons was going on, attempts were also being made to develop peaceful uses for nuclear fusion. The concept of a star power plant just outside the city was never out of sight for a number of nuclear scientists. 

Nuclear power is any method of doing work that makes use of nuclear fission or nuclear fusion reactions. hi its broadest sense, the term refers to both the uncontrolled release of nuclear energy, as in fission or fusion weapons, and to the controlled release of energy, as in nuclear power plants. Most commonly, however, the expression nuclear power is reserved for the latter. Approximately 430 nuclear reactors devoted to the manufacture of electricity are operating worldwide. 

Hydrogen bomb—An nuclear explosive weapon which uses hydrogen isotopes as fuel and an atom bomb as a detonator. More powerful than an atom bomb, the Hydrogen bomb derives its destructive power from energy released when nuclei of hydrogen are forced together to form helium nuclei in a process called nuclear fusion. Also called H-bomb or Thermonuclear bomb. 

Perhaps you are familiar with the terms nuclear fission and nuclear fusion. Nuclear fission is the process by which a relatively massive nucleus is divided into smaller nuclei and one or more neutrons. Nuclear fission is the process that generates so much power in nuclear power plants and in certain types of nuclear weapons, such as the bombs that were dropped on Japan in 1945. The following equation shows an example of nuclear fission (the nuclear fission of uranium-235) ... 

One of most important aspects of the Cold War was the race to develop and deploy nuclear weapons. The early arms race was largely focused on nuclear fission, but by the 1950s the much more powerful fusion weapons were the main area of development. The competition, however, was not only military, and the quest for new elements became a minor but important competition, primarily between American laboratories and Soviet ones. Because the equipment used to do nuclear research was used to produce elements and material for weapons, the link between the synthesis of new elements and the arms race was direct if one side could produce a new element, it revealed that that side s equipment, resources, and scientists had an advantage over the opposition. Since the equipment, resources, and scientists were also part of the nuclear arms development system, the implication was that the advantage would extend to the weapons. Even without the arms race, the competition to synthesize new elements was fierce, since international scientific status and even Nobel Prizes could be gained by such work. 

A nuclear application of lithium is in thermonuclear weapons and fusion research. In a weapon or fusion reactor, nuclear fusion occurs between two isotopes of hydrogen—deuterium and tritium. Deuterium occurs naturally and has an abundant supply in the worlds oceans (it is present in about 0.015 percent of water molecules). Tritium, on the other hand, is radioactive, has a relatively short half-life, and does not occur naturally. Tritium can be manufactured, however, by bombarding lithium 6 with neutrons. 

Nuclear fusion became important on Farth with the development of hydrogen bombs. A core of uranium or plutonium is used to initiate a fission reaction that raises the core s temperature to approximately 10 K, sufficient to cause fusion reactions between deuterium and tritium. In fusion bombs, LiD is used as Li reacts with fission neutrons to form tritium that then undergoes fusion with deuterium. It is estimated that approximately half the energy of a 50 megaton thermonuclear weapon comes from fusion and the other half from fission. Fusion reactions in these weapons also produce secondary fission since the high energy neutrons released in the fusion reactions make them very efficient in causing the fission of... 

A simple nuclear weapon derives its energy from nuclear fission. A mass of fissionable material is rapidly assembled into a critical mass, in which a chain reaction develops and releases tremendous amounts of energy. This is known as an atomic bomb. Nuclear fusion can be used to make a more powerful weapon. In such a weapon, the X-ray thermal radiation from a nuclear fission explosion is used to heat and compress a small amount of tritium, deuterium, or hthium, causing nuclear fusion, releasing even more energy. Such a weapon is called a hydrogen bomb and can be hundreds of times more powerful than an atomic bomb. 

Atomic bomb. A weapon of mass destruction. The term is sometimes taken to mean a nuclear weapon utilizing fission energy only, but it is applicable to hydrogen fusion weapons as well. It is appropriate to call both atomic weapons because the energy released by atomic nuclei is involved in each case. The energy of an atomic explosion is released in a number of ways ... 

Fission, nuclear. The splitting of a heavy atom accompanied by the emission of neutrons and gamma rays and the liberation of a large amount of energy. The nuclear fragments formed (fission products) are usually radioactive. Nuclear fission is the opposite of nuclear fusion. The most important and readily fissionable weapon materials are uranium 235 and plutonium 239. 

There are two different kinds of nuclear weapons. Weapons based on the fission process ( atomic bombs ) and weapons based on the nuclear fusion reaction ( hydrogen bombs ). The fusion weapons get most of their energy from a fusion process of fight nuclides (like deuterium) to helium. Fusion weapons contain a small fission bomb that serves to heat the fusion matter to a temperature of about 10 K required for the start of the fusion process. 

Nuclear fusion is also the basis of modem nuclear weapons called hydrogen bombs. A modem hydrogen bomb has up to 1000 times the explosive force of the first atomic bombs. These bombs employ the following fusion reaction. 

Nuclear Fusion Modem nuclear weapons are fusion bombs with 1000 times the power of the first fission bombs. Nuclear fusion is being explored as a way to generate electricity but has not yet proven successful. 

Tritium is radioactive, a weak p-emitter with a half-life of 12.3 yr. It is used extensively as a tracer, in both chemical and biochemical studies. Its weak radioactivity, rapid excretion and failure to concentrate in vulnerable organs make it one of the least toxic radioisotopes. A major use of tritium is in the triggering mechanisms of weapons based on nuclear fusion. 

As a result of the industrial use of U, commercially acquired U-containing chemicals or U standard solutions intended for elemental assay purposes will not necessarily have the natural isotopic composition, but will most often be depleted in U [66]. An unnatural isotopic composition may also be encountered for Li in chemicals, as it may be depleted in Li, as a result of its use as LiD as fusion fuel in thermonuclear weapons and in nuclear fusion [67]. 

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