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Effect of dissolved species on the corrosion of stainless steel in nitric acidCleland, Gareth Edward January 1998 (has links)
No description available.
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The effect of cerium and other rare earths on the nodule count, nodularity, nodule size and the matrix of the ductile ironAmin, Amar S., January 1977 (has links)
Thesis--Wisconsin. / Includes bibliographical references (leaves 76-77).
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Ab initio studies of anisotropic magnetism in uranium and cerium monopnictides and monochalcogenidesCollins, Eric Mason. January 2000 (has links)
Thesis (Ph. D.)--West Virginia University, 2000. / Title from document title page. Document formatted into pages; contains xiv, 110 p. : ill. (some col.). Includes abstract. Includes bibliographical references.
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The measurement of radiative electron capture and the nuclear spectra of Ce-144 and its decay products /Emmerich, Werner Sigmund January 1953 (has links)
No description available.
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Colloidal Cerium Oxide Nanoparticle: Synthesis and Characterization TechniquesClinton, Jamie C. 25 February 2008 (has links)
Fluorescence spectra and UV-Vis absorption spectra are collected on cerium oxide nanocrystalline particles. While CeO2 is the stable form of bulk cerium oxide, ceria nanoparticles exhibit a nonstoichiometric composition, CeO2-γ, due to the presence of oxygen vacancies and the formation of Ce2O3 at the grain boundaries. The Ce(III) ions, which are more reactive and therefore more desirable for various applications, are created by oxygen vacancies, which act as defects in the CeO2-γ crystal lattice. These defects form trap states in the band gap of CeO2, which can be seen in the absorption spectra. Ce(III) is required for fluorescence of the ceria nanoparticles while Ce(IV) is involved in only nonradiative transitions. The optical spectroscopy results show that the ceria samples have different ratios of Ce(III) ions to Ce(IV) ions, which is verified by x-ray photoemission spectroscopy (XPS). / Master of Science
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Tunable UV lasersMcGonigle, A. J. S. January 2000 (has links)
No description available.
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Ceria based emission control catalystsDaniell, Wayne January 1997 (has links)
No description available.
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A microscopic study of the interaction between aliovalent dopants and native defects in group IV oxides : indium and cadmium in ceria and zirconiaZacate, Matthew O. 11 March 1997 (has links)
In order to understand better the defect structure and dynamics associated
with lower valent dopants complexed with native defects in group IV oxides, In/Cd
perturbed angular correlation spectroscopy was performed in ceria and zirconia. Examining
the orientation symmetry axis of defects in ceria single crystals at low temperature
has allowed the identification of a cadmium with a bound near-neighbor
oxygen-vacancy complex as well as a complex involving a cadmium with two opposing,
near-neighbor oxygen vacancies. The orientation of the symmetry axis of a third
complex is reported; however, this information is not sufficient to identify it. Complementing
these low temperature studies, the dynamics of the cadmium/oxygen-vacancy
interaction in zirconia at high temperatures was studied. The motion of the oxygen
vacancy at high temperatures results in a damping of the PAC signal. This damping
is not well characterized by the heuristic Marshall-Meares PAC fitting function, and
a model is proposed to fit the data in terms of three physical parameters associated
with the vacancy's motion. These parameters are the rate at which a bound oxygen
vacancy hops among equivalent sites about the probe, the rate at which a bound
vacancy detraps, and the rate at which a vacancy is trapped by cadmium. Fits of
individual spectra using this model give respective activation energies of 0.3-0.6 eV,
0.9-1.6 eV, and 0.4-0.6 eV. The uncertainty in these energies can most likely be
reduced by fitting spectra from multiple temperatures simultaneously. Despite the
large uncertainty in the fitted energies, the values are physically reasonable and indicate
that the model adequately describes the motion of the oxygen vacancy about
cadmium. / Graduation date: 1997
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Titanium, zirconium, and cerium compounds containing an oxygen tripodal ligand /Yi, Xiao-Yi. January 2007 (has links)
Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2007. / Includes bibliographical references. Also available in electronic version.
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Production of cerium oxide microsheres by an internal gelation sol-gel processWegener, Jeffrey J. 14 January 2010 (has links)
The experiments performed for this research were completed to produce solid
cerium oxide microspheres by an internal gelation sol-gel process. The motivation for
this work was to develop a process that would enable the fabrication of a storage or
transmutation form for the plutonium and transuranics (TRU) from the Uranium
Extraction Plus (UREX ) used fuel reprocessing process. This process is being
investigated by the Department of Energy (DOE) and the Advanced Fuel Cycles
Initiative (AFCI) through the Nuclear Energy Research Initiative.
The internal gelation production of cerium oxide involves the combination of
hexamethylenetetramine (HMTA), urea, and cerium nitrate solutions at ~100oC.
Microspheres were produced by injection of a broth solution into a flowing stream of hot
silicone oil. The captured microspheres were aged, washed, and then underwent
Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), and XRay
Diffraction (XRD) analysis. The process variables examined in this study include
the concentrations of HMTA, urea and cerium nitrate, the process temperature, the postgelation
aging time, and the product washing conditions. Over a series of 70 experiments, it was determined that a broth solution
containing a mixture of 1.45 M cerium nitrate and 1.65 M HMTA and urea (1:1 ratio)
solutions produced the best cerium oxide microspheres. The spheres were aged for 30 to
60 minutes and then washed in hexane to remove the silicone oil and a subsequent series
of ammonium hydroxide washes to remove unreacted product and to fully gel the
microspheres.
Through DSC analysis it was determined that excess wash or unreacted product
may be removed by an exothermic reaction at approximately 200oC. The XRD analysis
of unheated spheres showed the presence of cerium oxide with additional cerium-bearing
organics. Following heating, the microspheres were completely converted to cerium
oxide.
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