Nickel nuclides

The nuclear y-resonance effect in ° Ni was first observed in 1960 by Obenshain and Wegener [2]. However, the practical application to the study of nickel compounds was hampered for several years by (1) the lack of a suitable single-line source, (2) the poor resolution of the overlapping broad hyperfine lines due to the short excited state lifetime, and (3) the difficulties in producing and handling the short-lived Mossbauer sources containing the Co and Cu parent nuclides, respectively. 

Nickel-62 is the nuclide with the greatest binding energy of all the elements. 

In December 1994, the nuclide roentgenium-272, niRg, was made from the bombardment of bismuth-209 atoms with nickel-64 atoms. Write a nuclear equation for this reaction. (One or more neutrons may be released in this type of nuclear reaction.)... 

In stars with very heavy average masses, helium burning may last for only a few million years before it is replaced by carbon fusion. In time this leads to the production of elements such as calcium, titanium, chromium, iron, and nickel fusion partly by helium capture, partly by the direct fusion of heavy nuclides. For example, two Si can combine to form Ni that can decay to Co which then decays to stable Fe. These last steps of production may occur rather rapidly in a few thousand years. When the nuclear fuel for fusion is exhausted, the star collapses and a supernova results. 

Even though the Mossbauer effect has been observed for almost 50 different elements and ca. 100 different nuclides, only a few of these elements are widely used as Mossbauer effect probes. The nuclides which are both experimentally viable and yield useful chemical information are iron-57, tin-119, antimony-121, and europium-151. More difficult to use but of importance in coordination chemistry are gold-197, nickel-61, ruthenium-99, tellurium-125, iodine-129, dysprosium-161, tungsten-182, and neptunium-237. Among these isotopes, iron-57 is by far the easiest, most informative, and most widely used nuclide in both traditional coordination chemistry and in studies of biologically significant coordination complexes. 

Because nuclides of iron are especially stable with the highest binding energy per nucleon (e.g., -8.79 MeV/nucleon for Fe), its cosmic abundance is particularly high, and it is thought to be the main constituent of the Earth s inner core as an iron-nickel alloy (see Section 13.2), named for its chemical composition NiPe by the Austrian geophysicist Suess. The relative Earth s crust abundance is about 5.63 wt.% Fe hence it is the fourth most abundant element after oxygen, silicon, and aluminum and the second most abundant metal after aluminum. 

As a very important topic in contamination buildup, the question is still open to what extent the data on corrosion product solubilities in the primary coolant are of importance for the behavior of trace amounts of cobalt. It seems to be still questionable whether cobalt ferrites as a well-defined compound with properties similar to the nickel ferrites can exist under PWR primary coolant conditions, whether cobalt atoms can be incorporated into a nickel ferrite lattice or whether traces of cobalt may be deposited onto the surfaces of the reactor core by adsorption on other, already deposited oxides. Such adsorption processes may occur even on the Zircaloy oxide films in the absence of any net deposition of corrosion products. Experimental investigations of the interaction of dissolved cobalt with heated Zircaloy surfaces (Lister et al., 1983) indicated that at low crud levels in the coolant cobalt deposition on surfaces is dominated by processes involving dissolved species, with adsorption/desorption processes being the responsible mechanisms. The extent of cobalt deposition is controlled by the type of oxide present on the Zircaloy surface thin black films of zirconium oxide will pick up less cobalt from the solution than thick white oxide films, even when the differences in the available surface areas of both types of oxides are taken into account. The deposition process seems to be little affected by the heat flux in the exposed metal. According to Thornton (1992), such adsorption-desorption exchange processes provide a pathway for radioactive species to be transported around the circuit even when the net movement of corrosion products is minimized this means that under such circumstances the processes of activity transport and of corrosion product transport may be decoupled. They may provide a pathway for target nuclides such as Co to be adsorbed onto fuel rod surfaces even in a core which is virtually free of deposited corrosion product particles. 

Which of the following nuclides have magic numbers of both protons and neutrons (a) helium-4 (b) carbon-12 (c) calcium-40 (d) nickel-58 (e) lead-208 ... 

Stainless steel is composed of iron (Fe), chromium (Cr), and nickel (Ni). What reactions would produce the following radioactive isotopes if stainless steel is irradiated in the reactor You may refer to a chart of the nuclides, and the short version of notation is acceptable (e g. Al-27(n,a)Na-24). 

Element 110 — In 1987 Oganessian, et 2il., at Dubna, claimed discovery of this element. Their experiments indicated the spontaneous fissioning nuclide 110 with a h2ilf-life of 10 ms. More recently a group led by Armbruster at G.S.I. in Darmstadt, Germany, reported evidence of 110, which was produced by bombarding lead for many days with more than 10 nickel atoms. A detector searched each collision for Element 1 lO s distinct decay sequence. On November 9,1994, evidence of 110... 

As for nickel alloys, type 625 and type 800 alloys have been considered for the steam cooled FBR concept by B W, GE, and WH [16]. Table 2.1 [9] shows an example composition of a nickel alloy and neutron absorption cross sections of each nuclide. From the viewpoint of neutron economy, materials with low thermal neutron absorption cross sections are more desirable for the cladding. It can be easily seen from Table 2.1 [9] that nickel has the dominant contribution to the neutron absorptions of the alloy. Chromium and iron also have relatively large contributions. Although boron has an especially large thermal neutron absorption cross section, since its content is very small, its influence is expected to be negligible on the neutron economy. 

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