Surface Fluorination of Nuclear Graphite Exposed to Molten 2LiF-BeF (FLiBe) Salt and Its Cover Gas at 700 °C.

This study demonstrates that the reaction of LiBeF (FLiBe) with graphite both in the liquid phase and the gas phase of the molten salt leads to the formation of covalent and semi-ionic carbon-fluorine bonds at the graphite surface and is accompanied by surface microstructural changes, removal of C-O groups, and deposition of metallic beryllium, based on XPS, Raman, and glow discharge mass spectroscopy characterization. At 700 °C, the observed surface density of C-F is higher after 240 h than after 12 h of exposure to molten FLiBe salt; the kinetics of covalent C-F formation is slower than that of semi-ionic C-F formation, and the relative amount of semi-ionic C-F content increases with depth. The graphite sample exposed to the cover gas exhibits less surface fluorination than the salt-exposed sample, with predominantly semi-ionic C-F.

Microstructural characterization data for nuclear graphite samples generated during tribology testing in argon.

This article contains microstructural characterization data related to the research article 'Self-lubrication of Nuclear Graphite in Argon at High Temperature', published in Digital, optical, and scanning electron micrographs are collected on the pebble and disk samples generated in the tribological tests and in their corresponding reference samples. Surface roughness measurements of the test and control samples are performed using the 3D-depth composition feature of the digital microscope. X-ray diffraction and Raman spectra of the test and reference samples are acquired and peak-fitted according to published literature on nuclear graphite characterization.

Factors associated with nutrition intervention adherence: Evidence from a cluster-randomised controlled trial in Kenya.

Nutrition experts point to the importance of a multipronged approach to address high stunting rates in rural areas. This can include nutrition-specific and -sensitive interventions, such as the provision of micronutrient powder, eggs, and chlorine, and nutrition training to improve feeding practices. In 2018, an agricultural nongovernmental organisation initiated a multipronged approach as part of a randomised trial.

Constant-potential molecular dynamics simulations of molten salt double layers for FLiBe and FLiNaK.

We report the results of constant-potential molecular dynamics simulations of the double layer interface between molten 2LiF-BeF (FLiBe) and 23LiF-6NaF-21KF (FLiNaK) fluoride mixtures and idealized solid electrodes. Employing methods similar to those used in studies of chloride double layers, we compute the structure and differential capacitance of molten fluoride electric double layers as a function of applied voltage. The role of molten salt structure is probed through comparisons between FLiBe and FLiNaK, which serve as models for strong and weak associate-forming salts, respectively.