bradley nemutudi - Academia.edu (original) (raw)
Papers by bradley nemutudi
Materials Today Communications
The density functional theory (DFT) was employed to investigate the oxidation mechanism and elect... more The density functional theory (DFT) was employed to investigate the oxidation mechanism and electronic structures of sperrylite (PtAs2) and platarsite (PtAsS) (100) surface. The cluster expansion (CE) and virtual crystal approximation (VCA) methods were used to construct the PtAsS models. The PtAsS constructed model by CE possessed symmetry of P213, while the VCA maintained the Pa-3 symmetry. The computed surface energies and morphologies for all surface models, depicted the (100) plane the preferred cleavage. The oxidation mechanisms of the (100) surfaces of sperrylite and platarsite favoured the mono atomic oxygen bonding, which resulted from the dissociation of the O2 molecule on the surfaces. The adsorption energies were more exothermic for PtAs2 (100) surface oxidation (–315.82 kJ.mol–1), suggesting that sperrylite highly oxidises than the platarsite mineral. The PtAsS (CE) (100) surface oxidises stronger than the PtAsS (VCA) (100) surface, which is owed to the less (100) surface stability of the PtAsS (CE) than for PtAsS (VCA). The partial density of states (PDOS) and Bader charges indicated that the adsorbed As, S and As/S atoms donate electrons to the O2 atoms. These finding clearly illustrated that the arsenide PGMs primarily oxidises through the As sites for sperrylite and As and S sites for platarsite. Therefore the study has demonstrated the oxidation behaviour of the sperrylite and platarsite platinum group minerals (PGMs) and unravelled the surface hindrance for collector interaction during floatation which results in poor floatability of arsenide PGMs.
Materials Today Communications, 2022
The density functional theory (DFT) was employed to investigate the oxidation mechanism and elect... more The density functional theory (DFT) was employed to investigate the oxidation mechanism and electronic structures of sperrylite (PtAs2) and platarsite (PtAsS) (100) surface. The cluster expansion (CE) and virtual crystal approximation (VCA) methods were used to construct the PtAsS models. The PtAsS constructed model by CE possessed symmetry of P213, while the VCA maintained the Pa-3 symmetry. The computed surface energies and morphologies for all surface models, depicted the (100) plane the preferred cleavage. The oxidation mechanisms of the (100) surfaces of sperrylite and platarsite favoured the mono atomic oxygen bonding, which resulted from the dissociation of the O2 molecule on the surfaces. The adsorption energies were more exothermic for PtAs2 (100) surface oxidation (–315.82 kJ.mol–1), suggesting that sperrylite highly oxidises than the platarsite mineral. The PtAsS (CE) (100) surface oxidises stronger than the PtAsS (VCA) (100) surface, which is owed to the less (100) surface stability of the PtAsS (CE) than for PtAsS (VCA). The partial density of states (PDOS) and Bader charges indicated that the adsorbed As, S and As/S atoms donate electrons to the O2 atoms. These finding clearly illustrated that the arsenide PGMs primarily oxidises through the As sites for sperrylite and As and S sites for platarsite. Therefore the study has demonstrated the oxidation behaviour of the sperrylite and platarsite platinum group minerals (PGMs) and unravelled the surface hindrance for collector interaction during floatation which results in poor floatability of arsenide PGMs.
Revista de Investigaciones Interculturales, 2021
La violencia contra la mujer es un problema que atañe a la sociedad contemporánea en diversos ámb... more La violencia contra la mujer es un problema que atañe a la sociedad contemporánea en diversos ámbitos. Inciden en su manifestación diversos factores. La presente investigación tuvo como objetivo general determinar la incidencia de los Factores Socioculturales en la violencia contra la mujer en casos atendidos en el Centro Emergencia Mujer Huancané -2017. El diseño fue de tipo básico – teórico que correspondió al nivel correlacional–causal. Se enmarca dentro del enfoque cuantitativo, utiliza el método hipotético deductivo y fue no experimental de corte transversal. Para el procesamiento de datos, se utilizó el diseño estadístico Chi cuadrado, como técnica se utilizó la encuesta con su instrumento cuestionario estructurado nominal. La población estuvo constituida por 108 mujeres víctimas de violencia. Los resultados demostraron que los factores socioculturales inciden significativamente en la violencia contra la mujer con un valor de x2 (28,664 > 5,9915). Entre estos factores se e...
Materials Today Communications
The density functional theory (DFT) was employed to investigate the oxidation mechanism and elect... more The density functional theory (DFT) was employed to investigate the oxidation mechanism and electronic structures of sperrylite (PtAs2) and platarsite (PtAsS) (100) surface. The cluster expansion (CE) and virtual crystal approximation (VCA) methods were used to construct the PtAsS models. The PtAsS constructed model by CE possessed symmetry of P213, while the VCA maintained the Pa-3 symmetry. The computed surface energies and morphologies for all surface models, depicted the (100) plane the preferred cleavage. The oxidation mechanisms of the (100) surfaces of sperrylite and platarsite favoured the mono atomic oxygen bonding, which resulted from the dissociation of the O2 molecule on the surfaces. The adsorption energies were more exothermic for PtAs2 (100) surface oxidation (–315.82 kJ.mol–1), suggesting that sperrylite highly oxidises than the platarsite mineral. The PtAsS (CE) (100) surface oxidises stronger than the PtAsS (VCA) (100) surface, which is owed to the less (100) surface stability of the PtAsS (CE) than for PtAsS (VCA). The partial density of states (PDOS) and Bader charges indicated that the adsorbed As, S and As/S atoms donate electrons to the O2 atoms. These finding clearly illustrated that the arsenide PGMs primarily oxidises through the As sites for sperrylite and As and S sites for platarsite. Therefore the study has demonstrated the oxidation behaviour of the sperrylite and platarsite platinum group minerals (PGMs) and unravelled the surface hindrance for collector interaction during floatation which results in poor floatability of arsenide PGMs.
Materials Today Communications, 2022
The density functional theory (DFT) was employed to investigate the oxidation mechanism and elect... more The density functional theory (DFT) was employed to investigate the oxidation mechanism and electronic structures of sperrylite (PtAs2) and platarsite (PtAsS) (100) surface. The cluster expansion (CE) and virtual crystal approximation (VCA) methods were used to construct the PtAsS models. The PtAsS constructed model by CE possessed symmetry of P213, while the VCA maintained the Pa-3 symmetry. The computed surface energies and morphologies for all surface models, depicted the (100) plane the preferred cleavage. The oxidation mechanisms of the (100) surfaces of sperrylite and platarsite favoured the mono atomic oxygen bonding, which resulted from the dissociation of the O2 molecule on the surfaces. The adsorption energies were more exothermic for PtAs2 (100) surface oxidation (–315.82 kJ.mol–1), suggesting that sperrylite highly oxidises than the platarsite mineral. The PtAsS (CE) (100) surface oxidises stronger than the PtAsS (VCA) (100) surface, which is owed to the less (100) surface stability of the PtAsS (CE) than for PtAsS (VCA). The partial density of states (PDOS) and Bader charges indicated that the adsorbed As, S and As/S atoms donate electrons to the O2 atoms. These finding clearly illustrated that the arsenide PGMs primarily oxidises through the As sites for sperrylite and As and S sites for platarsite. Therefore the study has demonstrated the oxidation behaviour of the sperrylite and platarsite platinum group minerals (PGMs) and unravelled the surface hindrance for collector interaction during floatation which results in poor floatability of arsenide PGMs.
Revista de Investigaciones Interculturales, 2021
La violencia contra la mujer es un problema que atañe a la sociedad contemporánea en diversos ámb... more La violencia contra la mujer es un problema que atañe a la sociedad contemporánea en diversos ámbitos. Inciden en su manifestación diversos factores. La presente investigación tuvo como objetivo general determinar la incidencia de los Factores Socioculturales en la violencia contra la mujer en casos atendidos en el Centro Emergencia Mujer Huancané -2017. El diseño fue de tipo básico – teórico que correspondió al nivel correlacional–causal. Se enmarca dentro del enfoque cuantitativo, utiliza el método hipotético deductivo y fue no experimental de corte transversal. Para el procesamiento de datos, se utilizó el diseño estadístico Chi cuadrado, como técnica se utilizó la encuesta con su instrumento cuestionario estructurado nominal. La población estuvo constituida por 108 mujeres víctimas de violencia. Los resultados demostraron que los factores socioculturales inciden significativamente en la violencia contra la mujer con un valor de x2 (28,664 > 5,9915). Entre estos factores se e...