On experimental determinations of transport properties of fused sodium fluoride (electrical conductivity, transport numbers of Na+ and self-diffusion coefficient of Na+ in molten sodium fluoride)

The transport properties of fused fluorides is virtually an unexplored field in the chemistry of fused salts. Some data on the electrical conductivities of alkali fluorides have been published, but large discrepancies exist between the measured values reported by different authors. In the present paper previously published results, on the electrical conductivity of fused sodium fluoride, are compared with the authors’ own measurements. Furthermore experimental data on transport properties and on the self-diffusion coefficient DNa+ in fused sodium fluoride are presented. The specific conductivity of molten fluoride was measured using a modified Thomson bridge. A frequency of 18 kHz was used. The conductivity was found to be (4.85 ± 0.09) Ω-1. cm-1 at 1 000 °C. The external transport number of Na+ in molten NaF was determined to be (0.64 ± 0.05) by a tracer technique. A boron nitride crucible was used as a diaphragm to separate the anolyte and the catholyte. The results were corrected with respect to the non-migration transfer of Na+ ions. The self-diffusion coefficient of Na+ in molten NaF was measured at various temperatures using a capillary technique. It was found that DNa+ = (3-08 ± 0.06) x 10-3 exp [(—8 700 ± 600) RT]

Effect of Coke Properties on the Bubble Formation at the Anodes During Aluminium Electrolysis in Laboratory Scale

The anodic reaction of aluminium electrolysis cells leads to the formation of CO2 bubbles, which partly screen the anode surface and leads to an increase in the cell voltage. An advantage of these bubbles is that the formation and release contribute to the stirring of the electrolyte, however, the screening of the surface increases the irreversible energy losses. The voltage and current oscillation due to the bubble evolution during electrolysis for different anode materials have been determined in a laboratory cell. The effect of coke sulphur content and grain sizes were investigated. Anodes with finer coke fraction showed lower oscillations than coarser fraction equivalents. Additionally, the influence of current density on the amplitude of the anode potentials was measured. A 64% increase of current density caused an increase of anode potential oscillations from 79 to 170%

Data from: A social-ecological database to advance research on infrastructure development impacts in the Brazilian Amazon

Recognized as one of the world's most vital natural and cultural resources, the Amazon faces a wide variety of threats from natural resource and infrastructure development. Within this context, rigorous scientific study of the region's complex social-ecological system is critical to inform and direct decision-making toward more sustainable environmental and social outcomes. Given the Amazon's tightly linked social and ecological components and the scope of potential development impacts, effective study of this system requires an easily accessible resource that provides a broad and reliable data baseline. This paper brings together multiple datasets from diverse disciplines (including human health, socio-economics, environment, hydrology, and energy) to provide investigators with a variety of baseline data to explore the multiple long-term effects of infrastructure development in the Brazilian Amazon

Data from: A social-ecological database to advance research on infrastructure development impacts in the Brazilian Amazon

Recognized as one of the world's most vital natural and cultural resources, the Amazon faces a wide variety of threats from natural resource and infrastructure development. Within this context, rigorous scientific study of the region's complex social-ecological system is critical to inform and direct decision-making toward more sustainable environmental and social outcomes. Given the Amazon's tightly linked social and ecological components and the scope of potential development impacts, effective study of this system requires an easily accessible resource that provides a broad and reliable data baseline. This paper brings together multiple datasets from diverse disciplines (including human health, socio-economics, environment, hydrology, and energy) to provide investigators with a variety of baseline data to explore the multiple long-term effects of infrastructure development in the Brazilian Amazon