Challenges and opportunities for a successful mining industry in the future

Modern models of sustainable economic growth are metal-intensive and will not be successful in the future unless a continuous supply of mineral-derived products is ensured. Despite this being logical, there is still a significant reluctance regarding mineral exploration and mining activities, often reflected in: (i) unfavourable public opinions; and (ii) absence of political measures or continuity of agendas that actually appreciate the way minerals are produced and the players directly or indirectly involved in this production. To succeed, the mining industry will have to (re)define its strategy and find innovative approaches to old problems and clearly demonstrate that mineral products can be efficiently delivered to support global development and assist suitable paths to welfare and quality of life, thus also providing real value to all concerned. In this study we give a concise review of the main challenges posed to the mining industry, and also indicate the most relevant opportunities and advance some proposals to constructively face the identified weaknesses and threats. The fundamental outcome is that the long-term balance between supply and demand of mineral products requires concerted actions on different fronts aiming: (i) the safeguarding of known resources; (ii) high-quality (scientifically and technologically driven) exploration surveys; (iii) improvements in mining and mineral transformation/ beneficiation; (iv) advances in consistent combinations of primary and secondary sources of raw materials, along with higher concerns on their judicious use; (v) effective and stable mining policies; and (vi) new insights on the role played by the mining industry through fruitful dialogues with society in general.info:eu-repo/semantics/publishedVersio

Current and Foreseen Tungsten Production in Portugal, and the Need of Safeguarding the Access to Relevant Known Resources

The economic and strategic importance of tungsten is widely recognized, but several concerns exist on its stable future supply. Portugal is one of the main tungsten producers in Europe, having generated ≈121 kt of contained tungsten in mineral concentrates from 1910 to 2020, i.e., ≈3.3% of the global production documented for the same time period. Since the early nineties, tungsten mining in Portugal is confined to the Panasqueira deposit which accounts for 79% of the country reserves (≈5.4 kt). However, according to the performed Generalized Verhulst and Richards curve-fitting forecasts, there is a significant future potential for increasing production in Portugal due to the low (<2%) depletion rates of the remaining known tungsten resources (≈141 kt). This projected growth is not necessarily guaranteed, depending on many unpredictable economic, technological, and political factors, besides appropriate social consents. Even so, a prudent land-use planning oriented to long-term needs should avoid the sterilization of the most relevant tungsten resources so far identified in the country. These are resources of “public importance”, as objectively demonstrated with a weighed multi-dimensional (geological, economic, environmental, and social) approach. Safeguarding the access to these resources does not implicate more than ≈6% of the Portugal mainland territory. The joint interpretation of results independently gathered for tungsten production forecasts and for the definition of areas hosting tungsten resources of public importance, provides additional support to political decisions on the urgent need to reconcile mineral exploration surveys and mining with other land uses.info:eu-repo/semantics/publishedVersio

Towards a multi-dimensional methodology supporting a safeguarding decision on the future access to mineral resources

A multi-dimensional methodology is proposed to delimit areas hosting mineral resources of public importance (MRoPI). The assessment procedure considers the Level of Geological Knowledge (LGK) along with the Economic (Ec), Environmental (Ev) and Social Development and Acceptance (SDA) dimensions. Different sets of independent, but complementary and variably weighed, criteria support the appraisal of each dimension, and a final score (MRoPI r ) results from a reasonable balance between LGK and (Ec + Ev + SDA). A ranking based on MRoPI r will fall in the [1, 10] interval, as imposed by the scaling normalising factor, but only specific tracts having MRoPI r  ≥ 4 display LGK values confident enough to be covered by a safeguarding decision at a given time. Adequate MRoPI r mapping can also be done, interpolating within the kriging formalism and evaluating thoroughly the modelling results until achieving the final map. The methodology application shows in addition that the combined use of LGK, Ec, Ev and SDA allows to address suitably two overlapping and coexisting, although different, issues: (1) safeguarding the future access to mineral resources and (2) planning the mineral development in the short-medium term, recognising the need of assigning specific areas to mining activities.info:eu-repo/semantics/publishedVersio

Computer tool for maximizing the placement of congruent polyhedra

Given multiple identical polyhedral objects and a parallelepiped container, how should one place the objects so that the largest number fits inside the container? This simple question is important in many applications, yet the answer is elusive. In fact, we know of no published solution for this very general formulation. Still, in many circumstances, further restrictions apply, resulting in a large number of variations requiring different algorithmic strategies. This paper is the continuation of [12] and focus on the fundamental concepts and tools that are used for this kind of problem, such as the no-fit polygon. We also present some of its many variations, giving in particular one that applies to the stereolithographic rapid prototyping technology

Relative Abundance and Compositional Variation of Silicates, Oxides and Phosphates in the W-Sn-Rich Lodes of the Panasqueira Mine (Portugal): Implications for the Ore-Forming Process

Panasqueira is a world-class W-Sn-Cu lode-type deposit located in Portugal. It consists of a dense swarm of subhorizontal quartz lodes criss-crossed by several ENE–WSW and N–S fault zones, bordering Late Variscan granite and hosted in Late Ediacaran—Early Cambrian metasediments. The relative abundance and compositional variation (assessed with EPMA) of the main silicates, oxides and phosphates forming the quartz lodes and their margins were examined, aiming to explore: (i) mineral and geochemical zonation at the mine scale; and (ii) some conclusions on the chemical nature of prevalent fluid inflows and T-conditions of mineral deposition. Quartz lodes nearby or far from the known greisen-granite cupola display significant differences, reflecting multiple fluid influxes of somewhat distinct composition related to various opening and closing events extending for several My, ranging from an early “oxide–silicate stage” (OSS) to a “main sulfide stage” (MSS), and further on to a post-ore carbonate stage (POCS); however, a rejuvenation event occurred after MSS. The onset of OSS was placed at ca. 299 ± 5 Ma and the rejuvenation event at ca. 292 Ma. The OSS was confined to ≈500 ≤ T ≤ 320 °C, following rutile and tourmaline growth under ≈640 ≤ T ≤ 540 °C (depending on aSiO2). The rejuvenation event (≈440–450 °C) preceded a late chlorite growth (≈250–270 °C) and the progression towards POCS.info:eu-repo/semantics/publishedVersio

Robotics and entrepreneurship for a better society: opening doors to mobility

This article reports the development of an educational robotics project at the Basic School (2nd and 3rd cycles) André Soares in Braga, with students from 6th grade, integrated in an international cooperative partnership for innovation and good practices of the European Erasmus+ programme. This project was initially designed to address the need to share innovative teaching practices through the development of new methodologies and multidisciplinary approach in teachinglearning processes in the 2nd and 3rd cycles of basic education combined with the stimulation of entrepreneurial skills and co-creation of knowledge. From the beginning, the project had the collaboration and support of the Hands-on Science Network Association, having given rise to the submission of an application to the 13th edition of the contest “Projeto Ciência na Escola” of the Ilídio Pinho Foundation on the topic “Science and Technology at the service of a better world”. This application has been selected for the 2nd phase of the competition and obtained financial support for the development of activities which gave an added dimension to the project, attracting and further motivating students for learning science and the choice of technology areas. Students were challenged to identify a situation/problem and find a possible solution/answer in the context of educational robotics. Thus, there was the study of the LEGO MINDSTORMS NXT programming environment for programming routines or scripts and simultaneously the work methodology hands-on was implemented using participative methodological approaches, enhancing the development of key skills and entrepreneur spirit. At first, students’ creativity was stimulated through the ideas generation process called SCAMPER, channelling it to solve situations/problem where the students' task was to unlock a situation and optimize it. From a simple stick and a simulation of a path for blind people, ideas were collected to innovate this object, in order to promote a more efficient and fairer mobility. With the collection/gathering of ideas/suggestions, a guiding principle for our project was developed giving an intended metacognitive knowledge. Starting with the acquisition of this knowledge, students focus on building and programming robots LEGO MINDSTORMS NXT, developing the prototype of a smart and innovative cane for the blind people. This is an interactive process that combines the concrete and the abstract in solving a problem involving steps such as: design, implementation, construction, automation and control mechanism. In all of these steps the construction of knowledge took place, arising from different scientific fields (science, mathematics, physics, technology), as well as the acquisition of transversal skills. The work focused mainly on the dynamics of the process rather than the products or results. Many citizenship skills were developed when creating a tool to minimize the difficulties and obstacles faced by blind people, enabling the improvement of their quality of life. It was observed, from certain experimental activities, that one can transfer new skills and knowledge acquired at school to everyday life

Irradiation damage on CrNbTaVWx high entropy alloys

ABSTRACT: CrNbTaVWx high-entropy alloys have been developed for plasma facing components to be applied in nuclear fusion reactors. The CrNbTaVWx (x = 1 and 1.7) compositions were prepared by ball milling and consolidated at 1600 degrees C under 90 MPa. To study the irradiation resistance of these materials, deuterium plasmas were used to irradiate the samples in the PF-1000U facility with 1 and 3 discharges. Structural changes before and after irradiation were analyzed by scanning electron microscopy coupled with energy dispersive X-ray spectroscopy. Nuclear reaction analysis was carried out with 1000 and 2300 keV 3He+ ion beams to evaluate the profile and amount of retained deuterium on the irradiated samples. After irradiation, the sample with higher W content revealed swelling and melting for all discharges, while in the case of CrNbTaVW only blisters were observed. The deuterium retention was higher for CrNbTaVW1.7 when compared with CrNbTaVW for 3 discharges applied.info:eu-repo/semantics/publishedVersio

Optimal dynamic control of laminated adaptive structures using a higher order model and a genetic algorithm

This paper deals with a finite element formulation based on the classical laminated plate theory, for active control of thin plate laminated structures with integrated piezoelectric layers, acting as sensors and actuators. The control is initialized through a previous optimization of the core of the laminated structure, in order to minimize the vibration amplitude. Also the optimization of the patches position is performed to maximize the piezoelectric actuator efficiency. The genetic algorithm is used for these purposes. The finite element model is a single layer triangular plate/shell element with 24 degrees of freedom for the generalized displacements, and one electrical potential degree of freedom for each piezoelectric element layer, which can be surface bonded or embedded on the laminate. To achieve a mechanism of active control of the structure dynamic response, a feedback control algorithm is used, coupling the sensor and active piezoelectric layers. To calculate the dynamic response of the laminated structures the Newmark method is considered. The model is applied in the solution of an illustrative case and the results are presented and discussed

Revis?o dos parasitas gastrointestinais em carn?voros selvagens na Europa

A proximidade dos animais silvestres ?s ?reas urbanas permite um maior contacto entre estes, os animais dom?sticos e o Homem, aumentando a probabilidade de transmiss?o de doen?as zoon?ticas. Grande parte das doen?as, nomeadamente as parasit?rias, que afetam humanos t?m origem em animais selvagens. Com este artigo pretendemos fazer uma revis?o dos estudos existentes na Europa sobre parasitas gastrointestinais de carn?voros selvagens, nomeadamente em lobo ib?rico (Canis lupus signatus), lobo europeu (Canis lupus lupus), raposa vermelha (Vulpes vulpes), lince ib?rico (Linx pardinus), marta (Martes martes), fuinha (Martes foina), texugo euroasi?tico (Meles meles) e gineta (Genetta genetta). Para o efeito, realizamos uma pesquisa bibliogr?fica online, nomeadamente nos sites PubMed e ResearchGate, colocando como palavras chave de pesquisa "parasites/parasitas" e o nome cient?fico dos diferentes carn?voros estudados. A maioria dos parasitas identificados correspondem a agentes potencialmente zoon?ticos (ancilostomat?deos, Taeniidae, Toxocara, entre outros), alertando para a import?ncia dos estudos epidemiol?gicos nesta ?rea, que podem gerar evid?ncias da necessidade de aplica??o de medidas profil?ticas para minimizar a dissemina??o destes agentes, em prol da manuten??o da sa?de ambiental, animal e humana.A91F-E8B8-FA62 | Teresa Susana Letra Mateusinfo:eu-repo/semantics/publishedVersio