2,586 research outputs found

    Biomass Valorization to Produce Porous Carbons: Applications in CO2 Capture and Biogas Upgrading to Biomethane—A Mini-Review

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    UIDB/50006/2020 UIDP/50006/2020 LA/P/0008/2020Porous carbon materials, derived from biomass wastes and/or as by-products, are considered versatile, economical and environmentally sustainable. Recently, their high adsorption capacity has led to an increased interest in several environmental applications related to separation/purification both in liquid- and gas-phases. Specifically, their use in carbon dioxide (CO2) capture/sequestration has been a hot topic in the framework of gas adsorption applications. Cost effective biomass porous carbons with enhanced textural properties and high CO2 uptakes present themselves as attractive alternative adsorbents with potential to be used in CO2 capture/separation, apart from zeolites, commercial activated carbons and metal-organic frameworks (MOFs). The renewable and sustainable character of the precursor of these bioadsorbents must be highlighted in the context of a circular-economy and emergent renewable energy market to reach the EU climate and energy goals. This mini-review summarizes the current understandings and discussions about the development of porous carbons derived from bio-wastes, focusing their application to capture CO2 and upgrade biogas to biomethane by adsorption-based processes. Biogas is composed by 55–65 v/v% of methane (CH4) mainly in 35–45 v/v% of CO2. The biogas upgraded to bio-CH4 (97%v/v) through an adsorption process yields after proper conditioning to high quality biomethane and replaces natural gas of fossil source. The circular-economy impact of bio-CH4 production is further enhanced by the use of biomass-derived porous carbons employed in the production process.publishersversionpublishe

    Temperature assessment in the drilling of ex vivo bovine and porcine cortical bone tissue

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    The drilling bone process is a common surgical procedure on medicine. The main concern in these surgeries is the thermal damage of the bone tissue induced by inappropriate parameters [1]. Objectives: Analyze the optimum cutting conditions that generate the lower temperature. Drill speed and the feed-rate effects were studied during the drilling of animal bones. Experimental tests were performed in laboratory and clinical environment

    Effect of wood flour as carbon source on cellulases and xylanases production by white-rot-fungi native from Misiones

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    There is a need to explore lignocellulosic materials to select an adequate substrate for lignocellulolytic enzyme production. Utilization of some residues provides an opportunity to produce high yields of lignocellulolytic enzymes in a simple medium. The aim of the present work was to study the effect of wood flour as a carbon source on the cellulolytic and xylanolytic secretion of white-rot fungi native from Misiones. Fungi were incubated with 5 g Pinus sp. wood flour/L and 5 g Eucalyptus sp. wood flour/L as carbon sources in a reciprocal shaker at 80 rpm and 29ºC for 15 days. Total cellulase, endo-1,4-β-glucanase, β-glucosidase, cellobiohydrolase and endo-1,4-β-xylanase activities were determined in culture supernatants. Tested fungi showed high endo-1,4-β-xylanase activity between 6 and 12 days. Total cellulase showed the highest activity between 12-15 culture days. The test did not show differences among Pycnoporus sanguineus LBM 014, P. sanguineus BAFC 2126, Irpex lacteus BAFC 1171, Irpex sp. LBM 032, Irpex sp. LBM 034 and Lenzites elegans BAFC 2127, showing the highest activity for this group regard the others strains. I. lacteus BAFC 1171 was the strain with major endo-1,4-β-glucanase activity at day 9 (847 U/L). In the case of β-glucosidase and cellobiohydrolase, P. sanguineus BAFC 2126 was the strain with the highest activity between 12-15 culture days (18 U/L), and between 9-15 culture days (39 U/L), respectively. Wood flour proved to be a suitable carbon source to produce hydrolytic enzymes. I. lacteus BAFC 1171 and P. sanguineus BAFC 2126 have potential for cellulase production whereas P. sanguineus LBM 008 is a good endo-1,4-β-xylanase producer.Fil: Rodríguez, María Daniela. Universidad Nacional de Misiones. Facultad de Cs.exactas Quimicas y Naturales. Departamento de Bioquimica Clinica. Laboratorio de Biotecnologia Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Barchuk, Mónica Lucrecia. Universidad Nacional de Misiones. Facultad de Cs.exactas Quimicas y Naturales. Departamento de Bioquimica Clinica. Laboratorio de Biotecnologia Molecular; Argentina. Comision Nacional de Investigacion Cientifica y Tecnologica; ChileFil: Fonseca, Maria Isabel. Universidad Nacional de Misiones. Facultad de Cs.exactas Quimicas y Naturales. Departamento de Bioquimica Clinica. Laboratorio de Biotecnologia Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Zapata, Pedro Dario. Universidad Nacional de Misiones. Facultad de Cs.exactas Quimicas y Naturales. Departamento de Bioquimica Clinica. Laboratorio de Biotecnologia Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Villalba, Laura. Universidad Nacional de Misiones. Facultad de Cs.exactas Quimicas y Naturales. Departamento de Bioquimica Clinica. Laboratorio de Biotecnologia Molecular; Argentin

    Assessing the ability of white-rot fungi to tolerate polychlorinated biphenyls using predictive mycology

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    The aim of the present study was to assess the ability of different white-rot fungi to tolerate polychlorinated biphenyls (PCBs) using predictive mycology, by relating fungal growth inhibition to ligninolityc enzyme secretion. Fungal strains were grown in the presence of PCBs in solid media and their radial growth values were modelled through the Dantigny-logistic like function in order to estimate the time required by the fungal colonies to attain half their maximum diameter. The principal component analysis (PCA) revealed an inverse correlation between strain tolerance to PCBs and the laccase secretion over time, being laccase production closely associated with fungal growth capacity. Finally, a PCA was run to regroup and split between resistant and sensitive fungi. Simultaneously, a function associated with a model predicting the tolerance to PCBs was developed. Some of the assayed isolates showed a promising capacity to be applied in PCB bioremediation. Abbreviations: Polychlorinated biphenyls (PCBs), white-rot fungi (WRF).Fil: Sadañoski, Marcela Alejandra. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Departamento de Bioquímica Clínica. Laboratorio de Biotecnología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; ArgentinaFil: Velázquez, Juan Ernesto. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Departamento de Bioquímica Clínica. Laboratorio de Biotecnología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; ArgentinaFil: Fonseca, Maria Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; Argentina. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Departamento de Bioquímica Clínica. Laboratorio de Biotecnología Molecular; ArgentinaFil: Zapata, Pedro Dario. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Departamento de Bioquímica Clínica. Laboratorio de Biotecnología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; ArgentinaFil: Levin, Laura Noemí. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; ArgentinaFil: Villalba, Laura. Universidad Nacional de Misiones. Facultad de Ciencias Exactas Químicas y Naturales. Departamento de Bioquímica Clínica. Laboratorio de Biotecnología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; Argentin

    Interaction between water and nutrient deficiencies in helianthus annuus

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    The physiological response of plants to water deficits are known to vary according to the conditions of application of drought stress and the rate of development of leaf water deficits. At the whole plant level the effect of the water shess is usually perceived as a decrease in photosynthesis and growth, and is associated with alterations in C and N metabolism (McDonald and Davies, 1996). The decrease in water potential affects transpiration and hence xylem transport of nitrate or reduced N into growing regions. The response of the photo-synthetic apparatus either to water stress or rehydration seems to be dependent "on leaf age (O'Neill, 1983; Wolfe et al., 1988). Degradation of both thylakoid and stromal N-containing compounds can occur in response to water stress, recovery from which may pequire more than a week (Chaves, 1991)

    Indoor air quality in healthcare units - a systematic literature review focusing recent research

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    The adequate assessment and management of indoor air quality in healthcare facilities is of utmost importance for patient safety and occupational health purposes. This study aims to identify the recent trends of research on the topic through a systematic literature review following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) methodology. A total of 171 articles published in the period 2015–2020 were selected and analyzed. Results show that there is a worldwide growing research interest in this subject, dispersed in a wide variety of scientific journals. A textometric analysis using the IRaMuTeQ software revealed four clusters of topics in the sampled articles: physicochemical pollutants, design and management of infrastructures, environmental control measures, and microbiological contamination. The studies focus mainly on hospital facilities, but there is also research interest in primary care centers and dental clinics. The majority of the analyzed articles (85%) report experimental data, with the most frequently measured parameters being related to environmental quality (temperature and relative humidity), microbiological load, CO2 and particulate matter. Non-compliance with the WHO guidelines for indoor air quality is frequently reported. This study provides an overview of the recent literature on this topic, identifying promising lines of research to improve indoor air quality in healthcare facilities.info:eu-repo/semantics/publishedVersio

    Temperature assessment in the drilling of composite materials and ex-vivo porcine bones

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    This study presents different experimental methodologies for analysis and temperature evaluation during the drilling process of composite materials and ex-vivo porcine bones. In the experimental methodologies were evaluated the influence of different parameters on the bone temperature rise. The combinations of different parameters produced temperatures far below the critical values. It was concluded that drill temperature decreases when the feed-rate is higher and, independently, increases with the increasing of hole depth. The influence of drill speed is not clear. In the composite materials the temperature decreases in the drill bit when the drill speed is higher, and in ex-vivo porcine bones happens the opposite. The animal models recorded lower temperature values than composite materials.The author of this paper acknowledges the support of the Project "Biomechanics: Contributions to the healthcare" co-financed by the Regional Operational Programme of North (ON.2 -The New North), the National Strategic Reference Framework (NSRF), through the European Development Fund (ERDF) and also to the project UID/EM/50022/2013 of LAETA financed by FCT

    Contextualizando a saúde da população negra

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    Unidade 1 do curso Saúde da População Negra, contendo 03 atividades. Tem como objetivo identificar a Política Nacional de Saúde Integral da População Negra - PNSIPN - enquanto estratégia de aumento do acesso ao SUS e melhorar a qualidade do cuidado na Unidade de Saúde

    El modelo de ayudas directas en la PAC post-2013: análisis de impactos de escenarios potenciales

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    Desde su introducción en 1992, las ayudas directas se han perfilado como uno de los principales instrumentos de apoyo al sector agrario de la UE. Este trabajo analiza potenciales escenarios de convergencia de las ayudas directas en la PAC post-2013. Se utiliza para ello el modelo CAPRI, que permite representar el funcionamiento de los mercados agroalimentarios a escala global así como incorporar las medidas de política agraria a nivel regional. Los resultados indican que un pago único más nivelado tendría impactos mínimos a nivel global de la UE pero conllevaría efectos redistributivos considerables, tanto entre regiones como entre Estados Miembros

    Enfrentamento do racismo institucional

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    Unidade 3 do curso Saúde da População Negra, contendo 4 atividades, cujo objetivo é atuar, pela perspectiva do cuidado, para implementação da Política Nacional de Saúde Integral da População Negra promovendo o acesso ao SUS e criando ou fortalecendo parcerias e redes de trabalho estratégicas no entorno da Unidade de Saúde
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