Thermonuclear weapon

The technologically most important isotope, Pu, has been produced in large quantities since 1944 from natural or partially enriched uranium in production reactors. This isotope is characterized by a high fission reaction cross section and is useful for fission weapons, as trigger for thermonuclear weapons, and as fuel for breeder reactors. A large future source of plutonium may be from fast-neutron breeder reactors. 

Uses of Plutonium. The fissile isotope Pu had its first use in fission weapons, beginning with the Trinity test at Alamogordo, New Mexico, on July 16, 1945, followed soon thereafter by the "Litde Boy" bomb dropped on Nagasaki on August 9, 1945. Its weapons use was extended as triggers for thermonuclear weapons. This isotope is produced in and consumed as fuel in breeder reactors. The short-Hved isotope Tu has been used in radioisotope electrical generators in unmanned space sateUites, lunar and interplanetary spaceships, heart pacemakers, and (as Tu—Be alloy) neutron sources (23). 

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. 

Lithium metal had few uses until after World War II, when thermonuclear weapons were developed (see Section 17.11). This application has had an effect on the molar mass of lithium. Because only lithium-6 could be used in these weapons, the proportion of lithium-7 and, as a result, the molar mass of commercially available lithium has increased. A growing application of lithium is in the rechargeable lithium-ion battery. Because lithium has the most negative standard potential of all the elements, it can produce a high potential when used in a galvanic cell. Furthermore, because lithium has such a low density, lithium-ion batteries are light. 

One of the reasons why thermonuclear weapons have to be serviced regularly is the nuclear decay of the tritium that they contain. Suppose a tritium sample of mass 1.00 g is stored. What mass of that isotope will remain after 5.0 a (1 a = 1 year) The decay constant of tritium is 0.0564 a-1. 

Einsteinium - the atomic number is 99 and the chemical symbol is Es. The name derives from Albert Einstein , the German bom physicist who proposed the theory of relativity. A collaboration of American scientists from the Argonne National Laboratory near Chicago, Illinois, the Los Alamos Scientific Laboratory in Los Alamos, New Mexico and at the University of California lab in Berkeley, California first found Es in the debris of thermonuclear weapons in 1952. The longest half-life associated with this unstable element is 472 day Es. 

Some compounds, such as strontium chromate and strontium fluoride, are carcinogens and toxic if ingested. Strontium-90 is particularly dangerous because it is a radioactive bone-seeker that replaces the calcium in bone tissue. Radiation poisoning and death may occur in people exposed to excessive doses of Sr-90. Strontium-90, as well as some other radioisotopes that are produced by explosions of nuclear weapons and then transported atmospherically, may be inhaled by plants and animals many miles from the source of the detonation. This and other factors led to the ban on atmospheric testing of nuclear and thermonuclear weapons. 

Helium is also the result of fusion reactions wherein the nuclei of heavy hydrogen are fused to form atoms of hehum. The result is the release of great amounts of energy. Fusion is the physical or nuclear reaction (not chemical reaction) that takes place in the sun and in thermonuclear weapons (e.g., the hydrogen bomb). 

Einsteinium does not exist in nature and is not found in the Earth s crust. It is produced in small amounts by artificial nuclear transmutations of other radioactive elements rather than by additional explosions of thermonuclear weapons. The formation of einsteinium from decay processes of other radioactive elements starts with plutonium and proceeds in five steps as follows ... 

The nature of thermonuclear war was made all too clear in the highly secret report of the Strath Committee in March 1955 on the home defence implications of thermonuclear weapons. William Strath had been seconded from the Treasury s Central Economic Planning Staff to set up the War Plans Secretariat, and his colleagues on the committee included representatives of the Chiefs of Staff, the Ministry of Defence (the Chief Scientist, Sir Frederick Bmndrett, and the Deputy Secretary, Sir Richard Powell), and the Home Office, including the Director-General of... 

Tritium is present naturally in the atmosphere, but the amounts were increased greatly in the late 1950s and 1960s by production and testing of thermonuclear weapons. Tritium is also a fission product and activation product produced in power reactors. Releases occur from reactors and reprocessing plants. Its use will increase greatly if fusion power is developed. 

In thermonuclear weapons, neutrons are absorbed in a blanket of 238U, where they induce fission and thus increase the power of the explosion. Neutron capture in 238U also produces 239Pu, 240Pu and 241 Pu. About 15 PBq (400 kCi) of Pu isotopes were disseminated by atmospheric testing of thermonuclear weapons, with a peak period in 1961-2 (Hardy et al., 1973). Most of the activity was carried into the stratosphere by the heat of the explosion. At ground level, there was a seasonal variation in the air concentration, similar to the seasonal variation in bomb-derived fission products and tritium (Fig. 4.1), with peaks in early summer,... 

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. 

Fields of interest adsorption, catalysis, cavitation, nuclear and thermonuclear weapons, shock waves, nuclear physics, particle physics, astrophysics, physical cosmology, and general relativity. Andrei Sakharov named him a man of universal scientific interests and Stephen W. Hawking said to Zel dovich Before I met you here, I believed you to be a collective author , like Bourbaki. See also Zel dovich theory in -> nucleation, subentry -> non-stationary nucleation, and -> Roginskii-Zeldovich kinetics in adsorption kinetics. 

The natural inventory of tritium produced by this reaction is about 4 x lO Bq (11 kg), of which 90% is contained in the ocean as HTO. The tritium produced by man s activities (largely thermonuclear weapons testing) has increased to approximately 2 x 10 ° Bq. Although most of this tritium has been transferred to the oceans, environmental tritium is still half an order of magnitude higher than was present before nuclear testing. 

The Odeillo results are in good agreement with earlier flash tube and arc image furnace work associated with the simulation of thermonuclear weapons effects. They are also in concord with earlier Princeton work on biomass gasification. 

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