Results 171 to 180 of about 464,807 (207)

Synthesis of Colloidal Uranium−Dioxide Nanocrystals

Journal of the American Chemical Society, 2006
In this paper, we have developed an organic-phase synthesis method for producing size-controlled, nearly monodispersed, colloidal uranium-dioxide nanocrystals. These UO2 nanocrystals are potentially important to applications such as nuclear fuel materials, catalysts, and thermopower materials.
Huimeng, Wu, Yongan, Yang, Y Charles, Cao   +2 more
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Nonstoichiometry in uranium dioxide

Journal of Nuclear Materials, 1974
Abstract Thermodynamic properties of uranium oxides with O/U atomic ratios between 2.04 and 2.34, principally in the nonstoichiometric UO 2+x single-phase region, were determined at temperatures in the range 500°C to 1100°C by electromotive force measurements with cells of the type Ni-NiO¦ZrO 2 (+CaO)¦uranium oxide.
openaire   +1 more source

Powder characteristics and microstructure of uranium dioxide and uranium dioxide-gadolinium oxide fuel

Journal of Nuclear Materials, 1996
Three different fuels UO2-only, UO2-Gd203(5%), and UO2-Gd203(10%) were produced by sol-gel technique. Their powder characteristics such as flowability, BET surface area, average pore diameter, and cumulative pore volume were determined. The pore size distributions of powders, green pellets, and sintered fuels were determined by using a mercury ...
Güngör Gündüz, İbrahim Uslu
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ChemInform Abstract: ELECTROCHEMICAL STUDY OF URANIUM DIOXIDE(2+)‐URANIUM DIOXIDE(+)‐URANIUM DIOXIDE SYSTEM IN MOLTEN LITHIUM CHLORIDE + POTASSIUM CHLORIDE

Chemischer Informationsdienst, 1981
AbstractFür die.Elektroreduktion von UO22+, die gemäß Schema A in 2 Stufen über intermediär gebildetes UO2+ erfolgt, werden die Standardpotentiale gegen 1M Pt(II)/Pt 450° C ermittelt und die Gleichgewichtskonstante der Disproportionierungsreaktion B zu K = 10‐3,0 mol dm‐3 berechnet.
I. UCHIDA, J. NIIKURA, S. TOSHIMA
openaire   +1 more source

New metallographic techniques for the examination of uranium, uranium alloys and uranium dioxide

Journal of Nuclear Materials, 1961
Abstract An attack-polish reagent has been developed for the metallographic preparation of uranium alloys and uranium dioxide. The reagent consists of a slurry of hydrogen peroxide (30 wt %) and 5 % γ-alumina. Polishing is carried out on a polythene lap covered with terylene velvet.
J.F.R. Ambler, G.F. Slattery
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Equations of state and isobaric potentials of uranium and uranium dioxide

International Geology Review, 1982
To investigate the possibility that uraninite might exist at great depths, thermodynamic calculations for the reaction - U + O/sub 2/ = UO/sub 2/ - were made.Pressures and temperatures selected corresponded to those of the mantle and outer core of the Earth.
T. B. Karpinskaya, I. A. Ostrovskly
openaire   +1 more source

Oxygen and uranium diffusion in uranium dioxide (a review)

Journal of Nuclear Materials, 1969
Abstract Oxygen and uranium self-diffusion coefficients determined experimentally by a variety of techniques are reviewed and compared. In the case of oxygen selfdiffusion for essentially stoichiometric UO 2 , the expression, D = 1.15 exp(−56700 ± 1000/ RT )cm 2 /sec, fits the data for three separate sets of observations covering a range of 10 ...
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Simulation of diffusion of oxygen and uranium in uranium dioxide nanocrystals

Journal of Nuclear Materials, 2008
The method of molecular dynamics is used to study phase transitions and ion transport phenomena in uranium dioxide nanocrystals. The temperature dependences of uranium and oxygen diffusion coefficients in the range from 2280 to 3950 K are calculated separately for surface, near-surface and bulk regions of the crystals.
A.Ya. Kupryazhkin, A.N. Zhiganov, D.V. Risovany, K.A. Nekrassov, V.D. Risovany, V.N. Golovanov   +5 more
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The conversion of uranium hexafluoride to dioxide

Soviet Atomic Energy, 1982
The processing of uranium hexafluoride is considered in various publications, many of which deal with the production of oxides by high, temperature hydrolysis (pyrohydrolysis) [i4]. Apart from methods that provide a powder, it is also possible to produce a granulated oxide directly by pyrohydrolysis [4-8].
N. P. Galkin, U. D. Veryatin, I. F. Yakhonin, A. F. Lugonov, Yu. M. Dymkov   +4 more
openaire   +1 more source

Raman scattering in uranium dioxide

Philosophical Magazine, 1966
Abstract The first-order Raman effect in uranium dioxide has been measured using a backward-scattering technique. The value obtained for the triply degenerate, Γ25 + mode, agrees well with that from neutron scattering data.
P. G. Marlow, J. P. Russell, J. R. Hardy
openaire   +1 more source