Environmental Performance of a Solid Waste Monetization Process Applied to a Coal-Fired Power Plant with Semi-Dry Flue Gas Desulfurization

Mixing of semi-dry flue gas desulfurization solids and fly-ash from coal-fired power plants results in a solid waste contaminated by calcium sulfite. Therefore, it becomes useless for industry and is often landfilled. To support decision-making on process configurations to monetize this solid residue a gate-to-gate life cycle assessment was performed, considering three scenarios: BASE case – standard 360 MW power plant, CASE I – base plant adopting dry thermal oxidation treatment of spray dryer solids, CASE II ‒ bypass of desulfurization system. Cases I and II allow commercialization of the solid residue as class C fly-ash. Evaluated alternatives were compared based on quantitative potential environmental impacts, using United States Environmental Protection Agency waste reduction algorithm. Based on the results, the BASE case was more aggressive to the environment, due to solid waste production. CASE II increased photochemical oxidation and acidification potentials. CASE I was the more environmentally friendly but demands additional capital and operational expenditure

Expansion and access to high quality undergraduate courses in Brazil : other quality indicators for higher education

O artigo apresenta resultados parciais de pesquisa com foco na expansão e no acesso a cursos de graduação de alta qualidade avaliados pelo Sistema Nacional de Avaliação da Educação Superior (Sinaes). Discute aspectos que favorecem a compreensão da avaliação da qualidade da educação superior e do debate sobre o Estado avaliador e o Estado regulador. Focaliza as bases epistemológicas e a disputa pela concepção de qualidade no Sinaes capazes de provocar alterações no caráter formativo-emancipatório atribuído à avaliação. A análise de quatro cursos com maior expansão e de alta qualidade, reiterada nos três ciclos avaliativos (2004-2012), evidencia que a ampliação desses cursos não se dá no mesmo ritmo da que ocorre de forma geral. A reflexão mostra também que o Enade se consolida como métrica eficaz de qualidade, mas requer associação a outros indicadores.The article presents partial results of research focused on the expansion and access to high quality undergraduate courses according to Sinaes. It discusses aspects that favor the understanding of the evaluation of quality of higher education and the debate concerning the evaluative state and the regulatory state. It approaches the epistemological basis and the dispute for the conception of quality in the Sinaes that are able to change the formative-emancipatory evaluation of the exam. The analysis of four courses with greater expansion, and the repeated high quality in the three evaluation cycles (2004-2012) indicates that the expansion of high quality courses does not occur the rhythm of the overall expansion. The reflection also demonstrates that the Enade has consolidated itself as an efficient quality metric but its association with other indicators is required

Bi2Te3 and Sb2Te3 Thin Films with Enhanced Thermoelectric Properties for Flexible Thermal Sensors

The influence of substrate type in boosting thermoelectric properties of co-evaporated Bi2Te3 and Sb2Te3 films (with 400 nm-thick) is here reported. Optimized power factor values are 2.7 × 10−3 W K−2 m−1 and 1.4 × 10−3 W K−2 m−1 for flexible Bi2Te3 and Sb2Te3 films, respectively. This is an important result as it is at least 2 times higher than the power factor found in the literature for flexible Bi2Te3 and Sb2Te3 films. A flexible infrared thermopile sensor was developed with high detectivity (2.50 × 107 cm √HzW−1).This work is supported by FCT with the reference project UID/EEA/04436/2013, by FEDER funds through the COMPETE 2020—Programa Operacional Competitividade e Internacionalização (POCI) with the reference project POCI-01-0145-FEDER-006941. EMFV and JF is grateful for financial support through the FCT grants SFRH/BPD/95905/2013 and SFRH/BD/121679/2016

Molecular phylogeny of atractus (Serpentes, dipsadidae), with emphasis on Ecuadorian species and the description of three new taxa

Volume: 661Start Page: 91End Page: 12