Uranium other elements obtained from

Uranium (U) is a naturally occurring, radioactive element used as a source of nuclear fuel and other radioactive elements. Plutonium (Pu) is one of the elements obtained from the use of uranium as a nuclear fuel. The isotope Pu-238 emits radiation that is easily absorbed by shielding. Pu-238 is used as a power source in heart pacemakers and navigation buoys. Other isotopes of plutonium are used as nuclear fuel and in nuclear weapons. Plutonium is the starting material for the synthetic production of the element americium, which is used in smoke detectors. 

Problem Pitchblende is the most commercially important compound of uranium. Analysis shows that 84.2 g of pitchblende contains 71.4 g of uranium, with oxygen as the only other element. How many grams of uranium can be obtained from 102 kg of pitchblende ... 

Initially, the only means of obtaining elements higher than uranium was by a-particle bombardment of uranium in the cyclotron, and it was by this means that the first, exceedingly minute amounts of neptunium and plutonium were obtained. The separation of these elements from other products and from uranium was difficult methods were devised involving co-precipitation of the minute amounts of their salts on a larger amount of a precipitate with a similar crystal structure (the carrier ). The properties were studied, using quantities of the order of 10 g in volumes of... 

At the time of the discovery of radio-activity, about seventy-five substances were called elements in other words, about seventy-five different substances were known to chemists, none of which had been separated into unlike parts, none of which had been made by the coalescence of unlike substances. Compounds of only two of these substances, uranium and thorium, are radio-active. Radio-activity is a very remarkable phenomenon. So far as we know at present, radio-activity is not a property of the substances which form almost the whole of the rocks, the waters, and the atmosphere of the earth it is not a property of the materials which constitute living organisms. It is a property of some thirty substances—of course, the number may be increased—a few of which are found widely distributed in rocks and waters, but none of which is found anywhere except in extraordinarily minute quantity. Radium is the most abundant of these substances but only a very few grains of radium chloride can be obtained from a couple of tons of pitchblende. 

Seafloor hydrothermal alteration processes are important for the global geochemical cycles of many elements, and the record of these processes in the oceanic crust reveals much information about these cycles. Rather robust flux information can be obtained from a variety of elements that have rather low initial abundances in basalt (H2O, CO2, K2O, rubidium, caesium, uranium) or that are rather sensitive to alteration ( Sr/ Sr) and 5 0. Fluxes of many other elements are rather poorly constrained because of substantial primary magmatic variation. 

The three core samples obtained from Stack A, their interval samples and sized samples, were analyzed quantitatively for trace quantities of uranium and thorium. The three core samples were also analyzed for radium, uranium, and thorium isotopes. These data were used to indicate the radioactive elements present and their relationships to each other within the stack. 

The first transuranium elements, neptunium and plutonium, were obtained in tracer amounts from bombardments of uranium by McMillan and Abelson and by Seaborg, McMillan, Kennedy, and Wahl, respectively, in 1940. Both elements are obtained in substantial quantities from the uranium fuel elements of nuclear reactors. Only plutonium is normally recovered and is used as a nuclear fuel since, like 235U, it undergoes fission its nuclear properties apparently preclude its use in hydrogen bombs. Certain isotopes of the heavier elements are made by successive neutron capture in 239Pu in high-flux nuclear reactors (> 1015 neutrons cm-2 sec- ). Others are made by the action of accelerated heavy ions of B, C, N, O or Ne on Pu, Am or Cm. 

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