14 documents found, page 1 of 2
The potential of reprocessing Au and by-products from a tailing dam in the iron...
Lemos, M.; Valente, T.; Marinho-Reis, A.; Sequeira-Braga, A.; Fonseca, R.; Mata Filho, J.; Magalhães, M.As historical mine wastes have accumulated in storage facilities, the interest in studying the reuse of gold (Au) mining tailings has increased, yielding environmental and economic benefits. In the present study, a detailed evaluation of the Cuiaba tailing dam in Sabara, Minas Gerais (Brazil) was performed, answering a new legal framework and agreeing with a circular economy philosophy. The mineralogical analys...
Geochemistry and Mineralogy of Auriferous Tailings and Their Potential for Reus...
Lemos, M.; Valente, T.; Marinho Reis, P.; Fonseca, R.; Pantaleão, J.P.; Guabiroba, F.; Gregorio Filho, J.; Magalhães, M.; Afonseca, B.; Silva, A.R.Since the mid-nineteenth century, gold ores, mainly hosted in sulfides, have been processed at metallurgical plants located in Nova Lima, Brazil. The generated wastes have been accumulated over the years in tailings dams or in piles. These materials represent wasted from old circuits, as well as from plants still in production. In this study, geochemical, mineralogical, 3D modelling, and metallurgical analyses ...
Adding Value to Mine Waste through Recovery Au, Sb, and As: The Case of Aurifer...
Lemos, M.; Valente, T.; Marinho Reis, P.; Fonseca, R.; Guabiroba, F.; Mata Filho, J.G.; Magalhães, M.F.; Delbem, I.D.; Rebelo Diório, G.From the colonial era to modern times, gold mining has played a crucial role in shaping Brazil’s economy, culture, and landscape, particularly in the Iron Quadrangle region. Therefore, resulting waste has accumulated in tailings structures, either from deactivated circuits or plants still in production. The present study reveals the potential assessed based on a set of metallurgical tests, assuming specific sce...
Hydrochemistry, Elements Distribution and Their Potential Recoveries in Gold Me...
Lemos, M.; Valente, T.; Marinho Reis, P.; Braga, A.S.; Fonseca, R.; Guabiroba, F.; Mata Filho, J.G.; Magalhães, M.F.; Silva, A.R.; Bhering, A.P.Recovering metals from mining wastewater is important in minimizing environmental pollution and maximizing resource efficiency. For this, a characterization step and understanding the oc-currence of metals and other compounds are essential. The present study focused on waters from different mining dams containing metals such as Au, Cu, Ni, Zn, and sulfates, located in the Iron Quadrangle region, (Brazil). The r...
Sensitivity analysis and pre-feasibility of reprocessing Au from a tailings dam...
Lemos, M.; Valente, T.; Marinho Reis, P.; Fonseca, R.As historical waste has accumulated in dams, the interest in studying the feasibility of reusing mining tailings has grown, offering both environmental and economic advantages. However, given the unique characteristics of each site, conducting site-specific assessments is crucial. Building on a detailed evaluation of the Cocoruto Dam in Nova Lima, Minas Gerais, this study presents a technical feasibility and fi...
Access to information, concerns, myths and truths on food safety during COVID-1...
Lemos, M.; Maia, R.; Teixeira, P.Purpose: The COVID-19 pandemic raised questions and concerns about the possibility of transmission of SARS-CoV-2 via foods. While cases of COVID were rapidly rising, information related to the virus and ways of prevention was also increasing, with much of this information being provided by the media and the general population. In this context, this study had two main objectives: 1) To understand the doubts and ...
Validation of a LLME/GC-MS methodology for quantification of volatile compounds...
Coelho, Eduardo João Louro; Lemos, M.; Genisheva, Zlatina; Domingues, Lucília; Vilanova, Mar; Oliveira, J. M.Knowledge of composition of beverages volatile fraction is essential for understanding their sensory attributes. Analysis of volatile compounds predominantly resorts to gas chromatography coupled with mass spectrometry (GCMS). Often a previous concentration step is required to quantify compounds found at low concentrations. This work presents a liquidliquid microextraction method combined with GCMS (LLME/GCMS) ...
Reflections on the conservation challenges of scientific and technological objects
Lemos, M.; Tissot, I.The conservation of science and technology (S&T) heritage encompasses complex challenges. Among the reasons for this complexity are the S&T objects specific characteristics: the wide variety of materials, construction techniques and dimensions, and the existence of operating mechanisms. Present conservation methods are not fully adapted to the specificity of this heritage, requiring more research on S&T conserv...
The action of chemical and mechanical stresses on single and dual species biofi...
Gomes, I. B.; Lemos, M.; Mathieu, L.; Simões, M.; Simões, Lúcia C.The presence of biofilms in drinking water distribution systems (DWDS) is a global public health concern as they can harbor pathogenic microorganisms. Sodium hypochlorite (NaOCl) is the most commonly used disinfectant for microbial growth control in DWDS. However, its effect on biofilm removal is still unclear. This work aims to evaluate the effects of the combination of chemical (NaOCl) and mechanical stresses...
A internet e as redes sociais online nas eleições presidenciais portuguesas de ...
Lemos, M.; Alturas, B.A contínua expansão das Tecnologias de Informação, nomeadamente as relacionadas com a comunicação e a difusão dos computadores pessoais, tablets e smartphones ligados à Internet têm vindo a possibilitar uma profunda reformulação dos sistemas de divulgação de informação. Atualmente os políticos utilizam cada vez mais a Internet e as Redes Sociais Online cada vez mais como ferramentas de marketing político para i...