ln the distorted wave calculations, the distortion is introduced by scattering from both the Coulomb field and the nuclear optical potential. Distorted and plane wave stripping calculations were made in an attempt to fit the measured angular distributions. Angular distributions and excitation functions were - measured for the reactions Be/sup 9/ (He/sup 3/,n)C/sup 11/, (He/sup 3/, n) Be/sup 9/ and Cd/sup 13/(He/sup 3/,n)O/sup 15/, by time-of-flight techniwues. Thesis submitted to Louisiana State Univ., Baton Rouge.

The irradiation performance of nitrogen-containing oxide or carbide kernels was no better than that of analogous nitrogen-free compounds. Laboratory KMC values for ThO/sub 2/ agreed with in-reactor values. Laboratory KMC values were obtained from unirradiated dicarbide particles these values were in excellent agreement with previously published laboratory KMC data and did not appear to be inconsistent with in-reactor dicarbide KMC values. The in-reactor KMC values were apparently not dependent on the extent of fission, the fission of either /sup 233/U or /sup 235/U, or the presence of a SiC coating layer.

The theoretically-based kernel migration coefficient (KMC), (cm/sec) /sup 0/K/sup 2/ (/sup 0/K/cm)/sup -1/, is thus used to correlate the data.

Application of theory to the analysis of in-reactor migration data indicates that a solid-state diffusion process operating across the kernel controls the migration rate in fissioned Th/sub 0/./sub 84/U/sub 0/./sub 16/C/sub 2/, UO/sub more » 2/, ThO/sub 2/, and Th/sub 0/./sub 8/U/sub 0/./sub 2/O/sub 2/ particles. This phenomenon has been studied both in the laboratory and in-reactor for fuel kernels from the Th-U-C-O-N system. This fuel is subjected to a significant in-reactor temperature gradient that leads to migration of the fuel kernel up the temperature gradient and into the coating layers. Nuclear fuels for the high-temperature gas-cooled reactor (HTGR) consist of spherical kernels of actinide compounds contained within gastight pyrolytic carbon and SiC. Receipt Date: 31-DEC-70 Country of Publication: United States Language: English Subject: N20210* -Chemistry-Inorganic, Organic, & Physical Chemistry-Chemical Properties CARBIDES CARBON CHEMICAL REACTIONS HIGH TEMPERATURE NITRIDES OXIDES REACTION KINETICS TEMPERATURE THERMODYNAMICS URANIUM ALLOYS OXYGEN SYSTEMS/C-N-O-U, reactions in, at 1400 to 2000$sup 0$C, kinetic and thermodynamic studies on role of carbon in URANIUM ALLOYS AND SYSTEMS/C-N-O-U, reactions in, at 1400 to 2000$sup 0$C, kinetic and thermodynamic studies on role of carbon in CARBON SYSTEMS/C-N-O-U, reactions in, at 1400 to 2000$sup 0$C, kinetic and thermodynamic studies on role of carbon in NITROGEN SYSTEMS/C-N-O-U, reactions in, at 1400 to 2000$sup 0$C, kinetic and thermodynamic studies on role of carbon in OSTI Identifier: 4725509 Report Number(s): ORNL-TM-2715 CONF-690927-1 NSA Number: NSA-24-004261 DOE Contract Number: W-7405-ENG-26 Resource Type: Technical Report Resource Relation: Other Information: From International Conference on Heterogeneous Kinetics at Elevated Temperatures, Philadelphia, Pa. Authors: Lindemer, T B Leitnaker, J M Spear, K E Publication Date: Wed Jan 01 00:00: Research Org.: Oak Ridge National Lab., Tenn.

Carbon reactivity