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Tellurides and native elements in copper-zinc ores of manifestations «Zapadnoe» (Subpolar Urals, Russia)
(Universidad del Zulia, 2019)
A readily computable commodity price index: 1900–2016.
This article presents an extended version of Grilli and Yang (1988)’s non-fuel commodity price index (GYCPI) for the period of 1900−2016. Specifically, the annual index under consideration comprises thirty-six commodities: ...
An overview of the obtaining of biomass-derived gamma-valerolactone from levulinic acid or esters without H2 supply
(North Carolina State University. Department of Wood and Paper Science, 2021-08)
Gamma-valerolactone (GVL) is a highly reactive keto-lactone and a promising platform biomolecule, used as an additive for food and fuels, green solvent, and fuels precursor, among others. Its production from biomass usually ...
Supercontinent evolution and the Proterozoic metallogeny of South America
(2007)
The cratonic blocks of South America have been accreted from 2.2 to 1.9 Ga, and all of these blocks have been previously involved in the assembly and breakup of the Paleoproterozoic Atlantica, the Mesoproterozoic to ...
Fe3O4 Pyrolyzed Fe‐N‐C catalysts templated by Fe3O4 nanoparticles. Understanding the role of N‐functions and Fe3C on the ORR activity and mechanism
(2022)
Pyrolyzed non-precious metal catalysts have been proposed as an alternative to substitute the expensive and scarce noble metal catalysts in several conversion energy reactions. For the oxygen reduction reaction (ORR), the ...
Recuperación de oro de chatarra electrónica por extracción de solventes usando 2etil-hexanol y dibutilcarbitol
(2018-10-04)
RESUMEN:
En años recientes, la búsqueda de nuevas alternativas que permitan una alta recuperación y refinación de oro para obtener un metal de alta pureza comercial ha tenido un desarrollo notable, ya que el uso de éste ...
Lixiviación de minerales carbonaceos con tiosulfato de amonio para la recuperación de metales preciosos de oro y plata.
(Universidad Nacional de Trujillo, 2016)