142 research outputs found
Analysis of Behavior of Embankments on Soft Soils Geotechnical Investigations and Instrumentation Access of Embank Ments the Jitituba River Bridge
The present work will be analyzing the access embankments of the Jitituba River Bridge, placed on the Highway AL- 413, km 12,9 – São Luiz do Quintude, a small city next to Maceió, AL, Brazil, where this bridge was built, even before the access embankments. Due to the presence of a soft soil thick layer, that measures up to 12 meters of thickness, and to the construction sequence of the bridge embankments, there was a need to analyze not only its stability but also its general rupture and its vertical displacements, commonly considered in the projects of embankments of soft soils, as well as the stability to reduce the horizontal displacements and the consequent efforts to transverse the piles through the bridge. The solution adopted consisted in the construction of embankments by stages, allied to the use of prefabricated vertical drains and geotechnical instrumentation (Casagrande piezometers, plates of settlement an inclinometers) to control and follow the project performance. The geotechnical investigations consisted on field tests (standard penetration test SPT with natural water content profile and vane test) and lab tests (characterization, radial and vertical consolidation, compression triaxial UU and CIU). Starting from the project data given by Gusmão Associated Engineers and the geotechnical investigations and instrumentation, the behavior of the access embankments was analyzed in relation to the measures of pore-pressures, vertical and horizontal displacements, through the application of several methods and models proposed in the bibliography and of the comparison with other cases of embankments on soft soils. Standing out, the analyses of consolidation, compressibility and control of stability
Aqueous Biphasic Systems Comprising Natural Organic Acid-Derived Ionic Liquids
Despite the progress achieved by aqueous biphasic systems (ABSs) comprising ionic liquids (ILs) in extracting valuable proteins, the quest for bio‐based and protein‐friendly ILs continues. To address this need, this work uses natural organic acids as precursors in the synthesis of four ILs, namely tetrabutylammonium formate ([N4444][HCOO]), tetrabutylammonium acetate ([N4444][CH3COO]), tetrabutylphosphonium formate ([P4444][HCOO]), and tetrabutylphosphonium acetate ([P4444][CH3COO]). It is shown that ABSs can be prepared using all four organic acid‐derived ILs paired with the salts potassium phosphate dibasic (K2HPO4) and tripotassium citrate (C6H5K3O7). According to the ABSs phase diagrams, [P4444]‐based ILs outperform their ammonium congeners in their ability to undergo liquid–liquid demixing in the presence of salts due to their lower hydrogen‐bond acidity. However, deviations to the Hofmeister series were detected in the salts’ effect, which may be related to the high charge density of the studied IL anions. As a proof of concept for their extraction potential, these ABSs were evaluated in extracting human transferrin, allowing extraction efficiencies of 100% and recovery yields ranging between 86 and 100%. To further disclose the molecular‐level mechanisms behind the extraction of human transferrin, molecular docking studies were performed. Overall, the salting‐out exerted by the salt is the main mechanism responsible for the complete extraction of human transferrin toward the IL‐rich phase, whereas the recovery yield and protein‐friendly nature of these systems depend on specific “IL-transferrin” interactions.publishe
Fingerprints for mining products and wastes of the S. Domingos, Aljustrel and Neves Corvo mines : a sustainable perspective
Good's Buffer Ionic Liquids as Relevant Phase-Forming Components of Self-Buffered Aqueous Biphasic Systems
A series of new self-buffering ionic liquids (ILs) based on Good's buffers (GBs) anions and the tetrabutylphosphonium cation ([P4444]+) was here synthesized and characterized. The self-buffering behaviour of the GB-ILs was confirmed by measuring their protonation constants by potentiometry. Further, their ability to form aqueous biphasic systems with the biodegradable potassium citrate salt was evaluated, and further investigated for the extraction of proteins, using bovine serum albumin (BSA) as a model protein. If these ionic structures display self-buffering characteristics as well as a low toxicity towards the luminescent bacteria Vibrio fischeri, they were additionally found to be highly effective in the formation of ABS and in the extraction of BSA - extraction efficiencies of 100% to the IL-rich phase obtained in a single-step. The BSA secondary structure in the aqueous IL-rich solutions was evaluated through infrared spectroscopic studies revealing the protein-friendly nature of the synthesized ILs. Dynamic light scattering (DLS), "COnductor-like Screening MOdel for Real Solvents" (COSMO-RS), and molecular docking studies were finally carried out to better understand the main driving forces of the extraction process. The results suggest that van der Waals and hydrogen-bonding interactions are important driving forces of the protein migration towards the GB-IL-rich phase, while the molecular docking investigations demonstrated a stabilizing effect of the studied ILs over the protein.publishe
Fish larval performance fed with copepods (Acartia grani) and the dinoflagellate (Oxyrrhis marina) as supplement: the case of dusky grouper (Epinephelus marginatus)
info:eu-repo/semantics/publishedVersio
Multispectral and hyperspectral remote sensing as a source of knowledge in the Portuguese sector of the Iberian Pyrite Belt
ABSTRACT: Remote sensing is an invaluable tool to increase geological and mining knowledge, due to its screening view and variable discrimination and identification capabilities of the target materials. In this study an overview of remote sensing research developed and ongoing within the Portuguese sector of the Iberian Pyrite Belt (PSIPB) since 2000 is given. Multispectral and hyperspectral datasets were processed using hybrid methods, related both to general and detailed characterization, to: 1) support geological, mineral and hydrothermal mapping, 2) generate products derived from multivariate analysis and band ratios, 3) enhance correlation with radiometric data, 4) provide elements for environmental assessment concerning mining activity, 5) map Acid Mine Drainage (AMD) based on spectral field signatures, 6) quantify AMD based on high correlation mineralogical mapping, and 7) monitor AMD. The results highlight the importance of the quantitative digital support given by remote sensing tools within the Portuguese Sector of the Iberian Pyrite Belt (PSIPB), ruled by georesource exploitation in different stages of the Mine Lyfe Cycle.RESUMO: A deteção remota é uma ferramenta valiosa para aumentar o conhecimento geológico e mineiro, devido à visão sinótica e à capacidade variável de discriminação e identificação dos materiais-alvo. Neste trabalho dá-se uma visão geral da investigação através dos trabalhos de deteção remota desenvolvidos e em curso no Setor Português da Faixa Piritosa Ibérica (SPFPI) desde 2000. Os dados multiespectrais e hiperespectrais foram processados usando métodos híbridos quer para a sua caracterização geral quer detalhada para: 1) apoiar a cartografia geológica, de mineralizações e sistemas hidrotermais, 2) gerar produtos de análise multivariada e rácios de bandas, 3) melhorar a correlação com dados radiométricos 4) fornecer elementos para avaliação ambiental em áreas mineiras, 5) cartografar a drenagem ácida de mina (DAM) com assinaturas espectrais de campo, 6) quantificar a DAM através de cartografia mineralógica de alta correlação, e 7) monitorizar a DAM. Destaca-se a importância do suporte digital quantitativo dado por ferramentas de deteção remota no SPFPI, regido pela exploração de georrecursos em diferentes fases do Ciclo de Vida das Minas
Deteção remota multiespectral e hiperespetral como fonte de conhecimento no sector português da Faixa Piritosa Ibérica
ABSTRACT: Remote sensing is an invaluable tool to increase geological and mining knowledge, due to its screening view and variable discrimination and identification capabilities of the target materials. In this study an overview of remote sensing research developed and ongoing within the Portuguese sector of the Iberian Pyrite Belt (PSIPB) since 2000 is given. Multispectral and hyperspectral datasets were processed using hybrid methods, related both to general and detailed characterization, to: 1) support geological, mineral and hydrothermal mapping, 2) generate products derived from multivariate analysis and band ratios, 3) enhance correlation with radiometric data, 4) provide elements for environmental assessment concerning mining activity, 5) map Acid Mine Drainage (AMD) based on spectral field signatures, 6) quantify AMD based on high correlation mineralogical mapping, and 7) monitor AMD. The results highlight the importance of the quantitative digital support given by remote sensing tools within the Portuguese Sector of the Iberian Pyrite Belt (PSIPB), ruled by georesource exploitation in different stages of the Mine Lyfe Cycle.RESUMO: A deteção remota é uma ferramenta valiosa para aumentar o conhecimento geológico e mineiro, devido à visão sinótica e à capacidade variável de discriminação e identificação dos materiais-alvo. Neste trabalho dá-se uma visão geral da investigação através dos trabalhos de deteção remota desenvolvidos e em curso no Setor Português da Faixa Piritosa Ibérica (SPFPI) desde 2000. Os dados multiespectrais e hiperespectrais foram processados usando métodos híbridos quer para a sua caracterização geral quer detalhada para: 1) apoiar a cartografia geológica, de mineralizações e sistemas hidrotermais, 2) gerar produtos de análise multivariada e rácios de bandas, 3) melhorar a correlação com dados radiométricos 4) fornecer elementos para avaliação ambiental em áreas mineiras, 5) cartografar a drenagem ácida de mina (DAM) com assinaturas espectrais de campo, 6) quantificar a DAM através de cartografia mineralógica de alta correlação, e 7) monitorizar a DAM. Destaca-se a importância do suporte digital quantitativo dado por ferramentas de deteção remota no SPFPI, regido pela exploração de georrecursos em diferentes fases do Ciclo de Vida das Minas.info:eu-repo/semantics/publishedVersio
Fashion showcases design: perceptions of the showcase in the brazilian popular market
The present work aims to present the showcase, its relation with the building, with fashion and with the observer. The importance of this exhibition space extends from the aesthetic and communication functions to be part of a wide textile and clothing chain. This role integrates the whole cycle of creation, textiles, clothing and fashion accessories. For this article we used bibliographical references of design and fashion, as well as methodologies of photographic and ethnographic documentation, with application of focus groups. From the focus groups were identified descriptors related to emotional design. Such descriptors point to the emotions arising from memories, tastes and attitudes. These factors can lead to decisions and assist the wider knowledge of the target audience.- This work is supported by CNPq funding on the Programa Ciencias Sem Fronteiras - CSF by national funds within the scope of the project Processo no 203068/2014-9.info:eu-repo/semantics/publishedVersio
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