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With the increase use of plastics, there is currently a concern with the waste of materials, resulting in a series of challenges and opportunities for the waste management sector. In the present work, poly(ethylene terephthalate) (PET) foam was produced from recycled PET (RPET) from used water bottles. The recycled material was manually prepared and foamed in batches with the assistance of nitrogen gas as the physical blowing agent. RPET was characterized using Differential Scanning Calorimetry (DSC), Dynamic Mechanical Analysis (DMA), Fourier Transform Infrared Spectroscopy (FTIR) and Thermogravimetric Analysis (TGA). The influence of the pressure on the foam formation was studied and the results obtained showed that this variable influences the final product characteristics. To evaluate the behavior of the foams, their morphology, response to deformation when subject to compression and their thermal conductivities were studied. The morphology analysis showed that operating at higher-pressure results in bigger pore size but also in an increased pore size heterogeneous distribution, and foams that exhibit a higher thermal conductivity.

It is more important than ever that organizations make the most of their resources, reduce costs, optimize processes, and engage in continuous improvement. A lean philosophy presents itself as a management model that guides companies in this direction, but for the successful implementation of lean methodologies, human resources at all levels need to learn what it is and be engaged with it. Thus, there is a need to develop tools that would transmit the lean theoretical concepts in a practical and involved way. This chapter proposes the development of a tool that is the result of merging gamification and lean philosophy, developing a game for people without knowledge in this area, serving as an introduction to it, and demonstrating some applications of this philosophy. The practical result of the synergy created between strategies of gamification and training in lean methodologies is described.

Submitted by Eliana CEH/B (liliprata2000@gmail.com) on 2021-09-23T18:34:02Z No. of bitstreams: 1 Tese - Jose Victor Neto - 2020 - Completo.pdf: 9618418 bytes, checksum: 65d705fb1fd51e348ff48f9f29a0989a (MD5) Made available in DSpace on 2021-09-23T18:34:02Z (GMT). No. of bitstreams: 1 Tese - Jose Victor Neto - 2020 - Completo.pdf: 9618418 bytes, checksum: 65d705fb1fd51e348ff48f9f29a0989a (MD5) Previous issue date: 2020-12-10 Ce travail vise tout d’abord à comprendre les processus d’élaboration du roman à clef Chibé, du journaliste et magistrat brésilien Raimundo Holanda Guimarães, à la lumière des études sur l’anachronisme et l’émulation poétique; et, à titre secondaire, à analyser les approximations et les écartements entre ce roman et le roman Les bohémiens (1790), du libelliste français marquis de Pelleport, en mettant en évidence les aspects intratextuels qui les rapprochent, ainsi que les facteurs contextuels dans lesquels s’insérait chaque auteur, en les motivant, tels que nous le croyons, à choisir le genre roman à clef pour la production de leurs romans. Le roman à clef est un genre romanesque dans lequel de vraies personnes sont représentées en portant des noms fictifs pour cacher leurs identités. Situé au Village d’Apeú, Castanhal-PA, dans les années 1930, Chibé dépeint le comportement répréhensible de personnes très influentes dans le contexte local. Celles-ci, même cachées par des noms fictifs, avaient leurs identités facilement reconnues par le public lecteur, ce qui a provoqué une grande polémique et de graves revers à l’auteur, tels que des menaces de mort et la destruction de l’œuvre. L’appropriation de ce genre romanesque par Holanda Guimarães s’est faite, comme nous le défendons, à partir de l’émulation de l’également roman à clef Gabriela, cravo e canela, de Jorge Amado. À son tour, Pelleport a écrit Les bohémiens alors qu'il était emprisonné à la Bastille, accusé d’avoir publié des libelles infâmes contre la noblesse. Dans celui-ci, Pelleport a exposé au ridicule tous ceux qui ont collaboré à son arrestation, en utilisant des noms fictifs pour cela. À propos du roman à clef Chibé, nous envisageons réfléchir aux processus d’appropriation de ce genre romanesque par Holanda Guimarães, en contribuant ainsi à l’approfondissement des études sur la « poétique de l’émulation ». Nous chercherons à comprendre son processus d’élaboration du roman Chibé à partir de l’idée de « contexte d’émulation », qui consiste en un ensemble de facteurs, tels que les aspects biographiques et de personnalité de l’auteur, ainsi que des facteurs de conjoncture sociale dans laquelle il s’insérait, et qui, combinés, serviraient comme des moteurs au déclenchement du processus d’émulation littéraire. Au cours de notre parcours comparatif, nous mettrons en évidence le choix du genre roman à clef par les deux auteurs pour l’écriture de leurs œuvres, ainsi que la motivation vindicative qui les a poussés dans cette réalisation. Nous avons l’intention de comprendre la relation entre les circonstances biographiques et contextuelles dans lesquelles étaient insérés les deux auteurs et les motivations qui les ont amenés à choisir le genre roman à clé pour l’écriture de leurs œuvres respectives. Nous entendons contribuer avec les recherches menées ici aux études actuellement rares sur le roman à clef, afin d’apporter une nouvelle contribution au fructueux champ de recherche autour des relations littéraires entre le Brésil et la France O presente trabalho visa, primeiramente, compreender os processos de elaboração do roman à clef Chibé, do jornalista e magistrado brasileiro Raimundo Holanda Guimarães, à luz dos estudos sobre o anacronismo e a poética da emulação; e, em caráter secundário, analisar as aproximações e distanciamentos entre este romance e o romance Les bohémiens (1790), do libelista francês Marquês de Pelleport, destacando-se os aspectos intratextuais que os aproximam, assim como os fatores contextuais em que se inseria cada autor, os quais os motivaram, segundo acreditamos, à escolha do gênero roman à clef para a produção de seus respectivos romances. O roman à clef é um gênero romanesco em que pessoas reais são retratadas através de nomes fictícios para ocultar suas identidades. Ambientado na Vila do Apeú, Castanhal-PA, na década de 1930, Chibé retrata a conduta reprovável de pessoas bastante influentes no contexto local. Estas, mesmo ocultas por nomes fictícios, tiveram suas identidades facilmente reconhecidas pelo público leitor, o que gerou uma grande polêmica e sérios reveses ao autor, como ameaças de morte e a destruição da obra. A apropriação desse gênero romanesco por Holanda Guimarães se deu, conforme defendemos, a partir da emulação do também roman à clef Gabriela, cravo e canela, de Jorge Amado. Já Pelleport escreveu Les bohémiens enquanto esteve preso na Bastilha, acusado de ter publicado libelos infamantes contra a nobreza. Nele, Pelleport expôs ao ridículo todos os que colaboraram para sua prisão, utilizando-se para isso de nomes fictícios. Acerca do roman à clef Chibé, pretendemos refletir sobre os processos de apropriação desse gênero romanesco por Holanda Guimarães, contribuindo assim para o aprofundamento dos estudos em torno da “poética da emulação”. Buscaremos compreender seu processo de elaboração do romance Chibé a partir da ideia de “contexto de emulação”, que consiste em um conjunto de fatores, tais como os aspectos biográficos e da personalidade do autor, assim como de fatores da conjuntura social em que ele estava inserido, os quais, combinados, funcionariam como motores para o desencadeamento do processo de emulação literária. Durante nosso percurso comparativo, daremos destaque à escolha do gênero roman à clef pelos dois autores para a escritura de suas obras, assim como à motivação vingativa que os impeliu a essa empreitada. Pretendemos compreender a relação entre as circunstâncias biográficas e contextuais em que estavam inseridos os dois autores e as motivações que os levaram à escolha do gênero roman à clef para a escritura de suas respectivas obras. Pretendemos, com a pesquisa ora realizada, contribuir para os atualmente escassos estudos sobre roman à clef, de modo a propiciar mais um contributo ao profícuo campo de pesquisas em torno das relações literárias entre Brasil e França

This study demonstrated an in situ method for quantitative characterization of nanoscale electrostatic properties of as-grown multilayer-graphene (MLG) sheets on nickel by a combination of atomic force microscopy (AFM) and Kelvin probe force microscopy (KPFM). Large area epitaxial MLG sheet were grown on nickel by Hot Filament-Thermal chemical vapor deposition (CVD) technique. The high crystalline MLG sheets on nickel were confirmed by Raman spectroscopy that revealed average G-bandwidths in the range of ∼20 cm −1 . Herein, for the first time, the charge injection as well as subsequent charge diffusion over time on the MLG/nickel surface was demonstrated. The results unveiled that: (i) MLG surface can be either positively or negatively charged through injection process using Pt coated Si-based AFM probes; (ii) the charges accumulated and eventually reached to saturated concentrations of +4.45 (±0.1) μC/m 2 and −1.3 (±0.1) μC/m 2 , respectively; (iii) the charge diffusion coefficients on graphene surface were measured to be 1.50 (±0.05) × 10 −16 m 2 /s and 0.64 (±0.05) × 10 −16 m 2 /s for the positive and the negative charges, respectively. The discovery of charge injection in MLG may pave the way for designing a new class of energy harvesting devices. Additionally, our study demonstrated a technique for nano-patterning/charge lithography of surface charges by contact electrification, which could be a promising application to create charged nanostructures for next generation graphene based nanoelectronic devices.

Introduction: The development of industrial challenges in higher education classes are an interesting form of teaching and learning that may lead to the development of students’ vital skills. It contributes to the connection between context taught in the classroom with the real world, among other benefits. Objectives: Assignments to solve real problems presented by regional industrial corporations addressing production organization, production processes or productive innovation issues have been proposed, and students are requested to analyze them and seek integral technical and scientific solutions. Methods: The present paper presents data from six semesters where the assignment has been developed. Open inquiries have been developed and students, companies, and teachers have been inquired to evaluate its application and results. Results: Results indicate that after some initial resistance, student’s final perception is of satisfaction and validation of the methodology adopted. Conclusions: The same opinion is shared by companies and teachers. Moreover, this type of interaction seems to have a positive impact on the university-business relationship., Millenium - Journal of Education, Technologies, and Health, No. 11 (2020): Serie 2, n.º 11

Additive manufacturing has a great potential since it allows the production of objects with complex geometries, often without auxiliary tools, while still using a wide range of materials. An example is Fused Filament Fabrication (FFF), one of the technologies frequently referred to as 3D printing. One of the most widely used thermoplastic material in FFF is poly(lactic acid) (PLA). This polymer has superior mechanical properties compared to common polymers, in particular the modulus of elasticity, becoming a good substitute in agricultural applications and packaging. However, in sectors such as automotive and electronics, the application of PLA has some disadvantages, such as: low thermal resistance; low thermal deflection temperature; low crystallization rate and reduced impact resistance. With the rising demand for 3D printing solutions, especially for small size parts with specific properties, the development of new materials to suit those demands became of the utmost importance. Thus, one solution that has been adopted in recent years is the incorporation of nanoparticles in the thermoplastics. In this paper, an experimental setup was developed regarding the processing and characterization of two sets of PLA nanocomposites, one with carbon nanotubes (CNT) and another with graphene. The processed nanocomposites’ properties were tested through mechanical and melt flow index characterizations to study their suitability for 3D printing.

Additive Manufacturing (AM) is the forefront of advanced manufacturing technologies and has the potential to revolutionize manufacturing, with a dramatic change in the design and project paradigms. A comprehensive review of existent metal AM processes, processable materials, respective defects and inspection methods (destructive and non-destructive) is presented in a succinct manner. Particularly, the AM design optimization methodologies are reviewed and their threats and constraints discussed. Finally, an aerospace industry case study is presented and several cost-effective examples are enumerated.

With the emergence of flexible/stretchable electronics, flexible solar cells (SCs) are able to attract much academic and industrial attention due to its advantages of lightweight, foldability, low cost, and extensive applications. Wearable technology has become a hot topic in the tech industry in this few years, shirts that read wearer’s biological and physiological information are just beginning to make their way into society and will change the way that we interact with technology. The high strength and good electronic properties of graphene fiber make it a good candidate for some specific applications, such as wearable SCs, since it can be obtained at relatively low cost and it is amongst the strongest commercial yarns in existence. In this review, a summarized state of the art regarding wearable SCs is presented including several applications of graphene and its derivatives with their remarkable unconventional applications.

In recent years, oxidative stress has been recognized as one of the most common effects of nanoparticles in different organisms. Ficopomatus enigmaticus (Fauvel, 1923), a member of a large family of serpulidae polychates, is an important encrusting organism in a diverse set of marine habitats, from harbours to coral reefs. This species has been previously studied for ecotoxicological purposes, despite the lack of reported studies on this species biochemical response after exposure to different pollutants. For these reasons, and for the first time, a set of biomarkers related to oxidative status were assessed in polychaetes after 28 days of exposure. Furthermore, polychaetes metabolic performance and potential neurotoxicity were investigated. Results clearly demonstrated induced toxicity in the filter-feeder polychaetes after exposure to nanoparticles. Indeed, CNTs altered the biochemical and physiological status of F. enigmaticus, both in terms of energy reserves (reduction of protein and glycogen contents), oxidative status (expressed as damage in cell function such as protein carbonyl content and lipid peroxidation) and activation of antioxidant enzymes defences (Glutathione reductase, Catalase, Glutathione peroxidase and Glutathione S-transferases activities). The present study showed for the first time that this species can be used as a model organism for nanoparticle toxicology.

Photovoltaics is amongst the most important technologies for renewable energy sources, and plays a key role in the development of a society with a smaller environmental footprint. Key parameters for solar cells are their energy conversion efficiency, their operating lifetime, and the cost of the energy obtained from a photovoltaic system compared to other sources. The optimization of these aspects involves the exploitation of new materials and development of novel solar cell concepts and designs. Both theoretical modeling and characterization of such devices require a comprehensive view including all scales from the atomic to the macroscopic and industrial scale. The different length scales of the electronic and optical degrees of freedoms specifically lead to an intrinsic need for multiscale simulation, which is accentuated in many advanced photovoltaics concepts including nanostructured regions. Therefore, multiscale modeling has found particular interest in the photovoltaics community, as a tool to advance the field beyond its current limits. In this article, we review the field of multiscale techniques applied to photovoltaics, and we discuss opportunities and remaining challenges. © T. Abu Hamed et al., published by EDP Sciences, 2018., European Cooperation in Science and Technology: MP1406, The authors are grateful for the financial support by the COST Action MP1406 “MultiscaleSolar.”

O TEMA tem como missão a excelência científica e tecnológica em vários domínios da Engenharia Mecânica e áreas afins, de acordo com as necessidades da sociedade Portuguesa e do sector industrial e empresarial. As indústrias de manufatura e de processos tecnológicos deparam-se atualmente com desafios de competitividade sem precedentes. O competitivo mercado nacional e internacional exige às empresas que disponibilizem novos produtos (com valor tecnológico acrescentado), e soluções inovadoras e diferenciadores a um ritmo cada vez maior. Ao mesmo tempo, essas empresas devem necessariamente ser flexíveis de maneira a rapidamente se adaptarem às variações das condições de mercado, nomeadamente através da busca de parceiros estratégicos para as suas atividades de investigação e desenvolvimento. (...) TEMA’s mission is to achieve scientific and technological excellence in various fields of Mechanical Engineering and related areas, addressing the needs of Portuguese society and industries. Manufacturing and process technology industries are currently facing unprecedented competitiveness challenges. The competitive national and international market requires companies to offer new products (with added technological value), and innovative and differentiating solutions at an ever-increasing pace. At the same time, these companies must be flexible to rapidly adapt to changing market conditions, by seeking strategic partners for their research and development activities. (...) published

Due to unique chemical and physical properties, nanomaterials from the Graphene family are being increasingly introduced in all fields of science. The specific roles they can occupy within different applications are attracting increased attention by several industrial sectors. These carbon nanoparticles are released into the environment especially accumulating in aquatic systems. Since the discovery of graphene, a number of research actives are being conducted to find out the toxic potential of the Graphene family materials to different organism's models. Although their toxicity effects are well described for biomedical applications, few data were produced with the specific aim of assessing the toxic effects of these carbon nanomaterials in the aquatic environment. The purpose of this review is to compile up-to-date information on properties, applications and characterization methods of graphene family materials in aquatic environments and identified biological toxic impacts of these NMs, with special focus on graphene oxide based on the most recent literature. published

True excellence in higher education, namely in engineering, is a difficult concept to define and attain. Engineering programs tend to value the later years as the most important in terms of training and scientific depth, while the first years are relatively neglected. At the same time, there is still a tendency to look at teachers’ achievements in terms of research and knowledge, detached in a certain way from pedagogy. On the contrary, more focus should be put into analysing the profile of teachers and its adequacy to the different approaches needed across the years and course units of a master program. Added to this, are the distinct “perceived realities” between (i) what teachers see as a satisfactorily provided service, (ii) what students need and feel to be the quality of the learning experience, and (iii) what society expects (and will expect, in the future) from engineers. Different views and different alignments, from different stakeholders, require careful assessment and analysis, since the quality of the teaching and learning (as assumed in this study) is strongly related to an individual (or group) perception. In this paper, a methodology is introduced that involves the main stakeholders in defining the quality of teaching and learning, focused on the first year of engineering courses at the University of Aveiro (Portugal). For this, a set of meetings and discussion forums provided the required context for identifying attributes of the mentioned “perceived quality”. As an outcome, a new model is presented, inspired in methodologies usually applied within the field of product design and development. The first layer of results is presented, together with a preliminary analysis and discussion. Future steps towards the goal of defining the best profile of higher education teachers for achieving (a higher level of) excellence in engineering education are also indicated.

Submitted by Robertt Valente (robertt@ua.pt) on 2018-07-31T15:11:47Z No. of bitstreams: 1 A model for the effective engagement of all stakeholders in engineering education and its pilot implementation.pdf: 2073299 bytes, checksum: d00dfae7b0a428985240c8260310b1e4 (MD5) Approved for entry into archive by Diana Silva (dianasilva@ua.pt) on 2018-08-01T11:04:27Z (GMT) No. of bitstreams: 1 A model for the effective engagement of all stakeholders in engineering education and its pilot implementation.pdf: 2073299 bytes, checksum: d00dfae7b0a428985240c8260310b1e4 (MD5) Made available in DSpace on 2018-08-01T11:04:27Z (GMT). No. of bitstreams: 1 A model for the effective engagement of all stakeholders in engineering education and its pilot implementation.pdf: 2073299 bytes, checksum: d00dfae7b0a428985240c8260310b1e4 (MD5) Previous issue date: 2018-05-30 published

Weld lines occur when two melt streams are combined. They may result in purely cosmetic imperfections, but also may represent part failure if placed in an area on the plastic highly subjected to stress during service. Qualitative assessment of these structural and cosmetics defects is usually accomplished by conventional mechanical characterization, destructive by nature, such as tensile testing or dynamic mechanical analysis (DMA). Nanoindentation offers the possibility for quick quasi-nondestructive in situ testing, allowing for monitoring the changes that occur in the surface layer of a plastic micropart. In this study, a methodology for the assessment of the superficial properties: hardness (H) and reduced Young's modulus (Er) of micromolded parts was developed. The microparts, molded from Polyoxymethylene with two different sets of processing conditions were tested throughout the entire length and in the vicinity of the welding line. The observed hardness (H) and reduced Young's modulus (Er) suggest that there is a steady increase in both values along the weld line from the adjoining flow front point at the inner side of the micropart towards the outer edge. In addition, H and Er were found out to vary consistently with the alterations induced by the processing conditions. Fil: Zhiltsova, Tatiana. Universidade de Aveiro; Portugal Fil: Daga, Bernardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Frontini, Patricia Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Neto, Victor. Universidade de Aveiro; Portugal Fil: Oliveira, Mónica. Universidade de Aveiro; Portugal

Zinc oxide (ZnO) is a wide band gap (~3.37 eV) semiconductor. Thin film ZnO has many attractive applications in optoelectronics and sensors. Recently, nanostructured ZnO (e.g. ZnO quantum dot) has been demonstrated as a hyperbolic material; its dielectric function has opposite signs along different crystal axes within the mid-infrared, making it an interesting material for metamaterials and nanophotonics. Conventional sputtering deposition usually leads to the formation of polycrystalline ZnO films with randomly oriented grains and rough surface. This work demonstrated a solution-based process to grow ZnO thin films with highly oriented nanocrystals. Low-temperature plasmas were employed to modulate the microstructure and optical properties of the films. Such highly anisotropic nanostructured transparent semiconductor films may lead to interesting material properties in developing new optoelectronic devices.

Diamond films are very hard and very resistant therefore useful for tribological components, molding parts, among other applications. Adjusting the precursor gas ratio in the gas mixture, a transition from micro- to nanocrystallinity may be achieved. Nanodiamond films possess similar properties as polycrystalline diamond, but with a reduced surface roughness and, thus suitable for application as protective coating. The purpose of this work is to use glass coated with a nanodiamond layer by Hot Filament Chemical Vapor Deposition (HFCVD) as a potential protective layer of a photovoltaic solar cell.

Microinjection moulding has been in continuous growth due to its ability to quickly and inexpensively produce large amounts of microparts. Nevertheless, downscaling the macro-injection process requires a thoughtful comprehension of the physics underlying microinjection moulding. High surface-to-volume ratios in microparts require higher injection pressure and injection speed to prevent premature solidification. In these conditions, the interaction between the melt and mould channels are critical, due to the increase of friction, wear, or even adhesion, leading to a deterioration of the quality of the micromouldings. Proper coatings, with high wear resistance and heat transfer capacity and low friction coefficient at injection molding temperatures, may assist microinjection moulding. In this work, the behavior of polymeric flow in microcavities coated with nanocrystalline diamond is investigated. It is showed that the front flow benefits from the coating. Additionally, it is suggested that the diamond coating can act as a heat buffer, assisting the heat transfer mechanism in the polymer/mould interface at the flow stage.

Results of the preparation and characterization of graphene oxide–optical fiber coatings will be presented, considering its potential use for sensing applications. The coatings were deposited using the electrostatic self–assembly method, considering different parameters (average sheet size of the graphene oxide colloidal solutions, the number of the deposited layers and the coating methodology) and characterized through SEM and Raman analyses. Aiming to explore this scheme for sensing applications, graphene oxide-coated tilted fiber Bragg gratings were characterized to refractive index variations. An improvement on the sensitivity was obtained and this result suggests that this could be a promising research field for the development of a new line of sensors.

The goal of the research presented in this chapter is to study and develop an alternative methodology to produce painted chrome-plated polymer parts required by the automotive industry. Nowadays the automotive industry is substituting metal parts for plastic ones. However, these new plastic parts must detain the aesthetic and the main properties of the metal components, i.e. the metallic appearance is of utmost importance, as well as the “cold sensation” of metal.

We report an electrically conductive composite prepared by sintering ZnO and metallic Zn powders. Microstructure analysis combined with electrical conductivity studies indicated that when the proportion of metallic Zn reached a threshold (∼20 wt.%), a metal matrix was formed in accordance with percolation theory. This composite has potential as a sputtering target for deposition of high-quality ZnO. Use of the ZnO:Zn composite completely eliminates target poisoning effects in reactive sputtering of the metal, and enables deposition of thin ZnO films at rates much higher than those obtained by sputtering of pure ZnO ceramic targets. The optical transmittance of the ZnO films prepared by use of this composite is comparable with that of films produced by radio frequency sputtering of pure ZnO ceramic targets. The sputtering characteristics of the conductive ZnO:Zn composite target are reported, and possible mechanisms of the high rate of deposition are also discussed.

The characterization of different diamond coatings onto optical fibres is presented. The experimental conditions of each deposition were determined by the Taguchi method, considering five different parameters at four levels. With these experiences it was intended to find the suitable diamond deposition conditions for the optical fibres coating. The application of the Taguchi method demonstrated to be a fundamental tool in the targeting of the appropriate conditions to coating the fibre.

Amorphous carbon can be any mixture of carbon bonds of sp3, sp2, and even sp1, with the possible presence of hydrogen. The group of mixture, of which there is a high fraction of diamond-like (sp3) bonds, is named diamond-like carbon (DLC). Unlike the crystalline carbon materials: diamond, graphite, carbon nanotube, fullerene and graphene, DLC can be deposited at room temperature without catalyst or surface pretreatment. Furthermore, its properties can be tuned by changing the sp3 content, the organization of sp2 sites and hydrogen content, and also by doping. This paper firstly reviewed the electrochemical properties of DLC films and their applications.

The hardness, heat conductivity and low friction coefficient of microcrystalline diamond make it a suitable candidate for tribological applications. However, its roughness and high deposition temperature pose significant obstacles to these applications. We have successfully grown nanocrystalline diamond on steel at 400 °C by hot-filament chemical vapor deposition by employing a CrN interfacial layer. Nanocrystalline diamond combines hardness and surface smoothness required in tribological applications. Microcrystalline diamond and carbon nanotubes can also be grown by controlling the deposition parameters. The fabricated films were characterized with Raman spectroscopy, X-ray diffraction (XRD), Transmission electron microscopy (TEM), and scanning electron microscopy (SEM).

The concept of Smart City comprises many levels of development, quality of life and wellbeing. One of the key aspects of this idea is the relevance of the overall education of citizens, on technical competences as well as responsible citizenship. Within the innovation-focused drive to future cities, scientific literacy is paramount, particularly considering engineering education. This is noteworthy for the education of today's students, preparing them for life in tomorrow's multifaceted technology-driven world, and directing them to personal and professional development within scientific careers. This Chapter describes the challenges and opportunities of education within today's society paradigms, with an eye on the Smart Cities of the future. A new, innovative and connected approach is presented, with concepts that encompass the main stakeholders in the scientific education system along with the main actors in society. A global and scalable education framework model is detailed, aiming to provide guidelines for an improved collaborative approach to STEM education in the future.

The goal of the Methodologies for Engineering Learning and Teaching (MELT) approach is to enhance the attractiveness of education through science, technology, engineering and mathematics subjects, while promoting awareness of STEM careers during upper secondary school. As a consequence, its main goal is to take into account students' aspirations and expectations during university programs and beyond, leading to an increased engagement in STEM careers. To accomplish these goals, a new, innovative and connected approach is presented, with a concept that encompasses the main stakeholders in scientific education, along with the main actors in society. A global and scalable education framework model is presented, aiming to provide guidelines for an improved collaborative approach to STEM education in the future.

This paper describes a model (and the respective guidelines) for the creation of a debate “think-tank” around the thematic of Engineering Education. From this initiative, a first outcome is obtained, in the form of the Engineering Education Forum 2016 (EEF 2016). The Engineering Education Forum is therefore intended to be a place of discussion and debate on this thematic. The model behind Forum encompasses different approaches and tendencies, looking at the past, analysing the present and discussing the future. From the EEF 2016, several outputs and outcomes can be obtained and used for future strategies on Engineering Education. They are presented in this work, the first one focusing on preliminary quantitative results, regarding both the profiles of involved stakeholders and the responses of participants to a number of challenges proposed to the participants of the “face-to-face” debate. The second group of outcomes is related to qualitative aspects, such as the sessions' content and debates, as well as hints for future initiatives following the EEF model.

Buscamos contribuir para as pesquisas cientificas acerca da oralidade na Amazônia , quebrando com estigmas e mostrando que há, nessas narrativas uma maior complexidade gerada pelo hibridismo de elementos provenientes do imaginário nordestino que se mesclam a elementos do imaginário local, criando um espaço único e complexo de difusão cultural subalterna, de caráter heterogêneo e inter-relacionado.

The cultivation of sugarcane and production of its derivatives are closely linked to Brazil’s history and development. The factory managers face the problem of discarding the sugarcane bagasse ash (SBA), as these ashes are the final waste resulting from the industrial processes, with no possibility to reduce it. The objective of this study is to analyze the effect of adding SBA to compressed earth blocks (CEBs). Two sets of blocks were prepared with 6% and 12% of cement in addition to the earth and with the addition of SBA at ratios of 0%, 2%, 4% and 8% each. Compressive strength and absorption tests were performed on the blocks. Additionally, masonry prisms were produced with the set of blocks that showed the best preliminary test results. The results showed that the SBA can be incorporated into the CEBs and masonry without damage to the mechanical properties.

For a number of biomedical applications, including the development of phantoms for quality control of radiotherapy treatments and dose determination, it is important to study the radiation response of the used materials, in order to distinguish the relevant dose distribution modifications from the artifacts caused by the phantom material when subjected to high dose irradiation. Beside the radiation response, those materials should have certain physical and chemical properties in order to be able to be used for the purposes described above, i.e., mechanical hardness and inelasticity, chemically stability and nonreactive, among others. In this work, a wide range of polymeric materials were irradiated under megavoltage radiation using a radiotherapy linear accelerator. The irradiated materials were imaged using transmission X-ray tomography to determine if some radiation induced electronic density change could result in altered Hounsfield units. Furthermore, Raman Spectroscopy and X-ray Diffraction (XRD) techniques were used before and after irradiation in order to study any structural modification induced by the radiation. In addition, a special phantom simulating a breast treatment with two tangential beams has been fabricated and tested.

Nanocrystalline diamond films, as other forms of diamond, possess a set of extreme properties, such as high thermal conductivity, hardness and resistance to hazard environments. Although an enormous focus has been placed into the deposition of nanocrystalline diamond films, most of this research uses microwave plasma assisted CVD systems. However, the growth conditions used in microwave systems cannot be directly used in hot-filament CVD systems. In this paper, it is meant to enlarge the knowledge of the process of depositing nanocrystalline films on different engineering materials, by means of hot-filament CVD systems. The coated materials include silicon (Si); titanium (Ti); tungsten carbide with cobalt as binder (WC-Co); and tungsten carbide with nickel as binder (WC-Ni). On the former two substrates, the diamond films were achieved on the bare substrates and with the use of an interlayer. The interlayers used were chromium nitride (CrN) and titanium aluminium nitride (TiAlN). Additionally, the as-grown films were characterized for hardness, quality and microstructure using scanning electron microscopy, Raman spectroscopy and nanohardness testing.

The metabolites of three species of Apiaceae, also known as Pegaga, were analyzed utilizing (1)H NMR spectroscopy and multivariate data analysis. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) resolved the species, Centella asiatica, Hydrocotyle bonariensis, and Hydrocotyle sibthorpioides, into three clusters. The saponins, asiaticoside and madecassoside, along with chlorogenic acids were the metabolites that contributed most to the separation. Furthermore, the effects of growth-lighting condition to metabolite contents were also investigated. The extracts of C. asiatica grown in full-day light exposure exhibited a stronger radical scavenging activity and contained more triterpenes (asiaticoside and madecassoside), flavonoids, and chlorogenic acids as compared to plants grown in 50% shade. This study established the potential of using a combination of (1)H NMR spectroscopy and multivariate data analyses in differentiating three closely related species and the effects of growth lighting, based on their metabolite contents and identification of the markers contributing to their differences.

The ‘Ulam’, a traditional Malay dish, are plants that can be eaten raw, as a form of local salad. The shoots and young leaves of Melicope ptelefolia are among the popular species, believed to be high in nutritional and medicinal values. The metabolomic fingerprinting analysis of the ethanolic extracts of leaves of M. ptelefolia was carried out using 1 H Nuclear Magnetic Resonance (NMR) spectroscopy and multivariate data analysis in order to differentiate young and mature leaves and to evaluate the variation of their chemical composition. Principle component analysis (PCA) of the 1 H NMR spectra showed a clear discrimination between the young and mature leaves extracts by PC3 and PC4. The compounds responsible for the differentiation were identified by comparison of 1 H NMR chemical shifts and qualitative HPLC. The young leaves were found to be richer in fatty acids and the levels of the three marker compounds, p - O -geranylcoumaric acid, 2,4,6-trihydroxy-3-geranylacetophenone and 2,4,6-trihydroxy-3-prenylacetophenone, were clearly higher. The mature leaves contain higher levels of sugars and glycosidic components.

A mechanical seal promotes the connection between systems or mechanisms, preventing the escape of fluids to the exterior. Nonetheless, due to extreme working conditions, premature failure can occur. Diamond, due to its excellent properties, is heralded as an excellent choice to cover the surface of these devices and extend their lifetime. Therefore, the main objective of this work was to deposit diamond films over mechanical seals and test the coated seals on a water pump, under real working conditions. The coatings were created by hot filament chemical vapor deposition (HFCVD) and two consecutive layers of micro- and nanocrystalline diamond were deposited. One of the main difficulties is the attainment of a good adhesion between the diamond films and the mechanical seal material (WC-Co). Nucleation, deposition conditions, and pre-treatments were studied to enhance the coating. Superficial wear or delamination of the film was investigated using SEM and Raman characterization techniques, in order to draw conclusions about the feasibility of these coatings in the WC-Co mechanical seals with the purpose of increasing their performance and life time. The results obtained gave a good indication about the feasibility of this process and the deposition conditions used, with the mechanical seals showing no wear and no film delamination after a real work environment test.

The mould making industry is known to be worldwide in rapid expansion, due to the fact that polymeric based materials are increasingly replacing conventional used ones, thus placing enormous challenges on production methods and tools. The application of chemical vapour deposition (CVD) diamond coatings onto moulds can be a promising tool to improve properties such as adhesion, reduction on abrasion and corrosive wear, filling and releasing problems or even tool thermal fatigue. Despite its potential for use in these types of applications, diamond coating on steel substrates is not problem-free and a few critical problems such as adhesion to steel, process temperatures and film property control, remain to be solved. This paper reports on experimental results obtained from an investigation focusing on the deposition of diamond coatings onto steel substrates using the new time-modulated chemical vapour deposition process. Furthermore, the technique is evaluated in order to establish its suitability for application in mould production tools.

This paper reports on advancements in micromoulding tool inserts. Different surface coatings were used and their influence was observed in what concerns part dimensional stability and subsequent polymer finishing quality. A set of thermoplastic injection moulding inserts with a simple 3D structured feature and different surface treatments were used to produce HDPE moulded parts. Surface treatments employed included the deposition of two different types of CVD diamond coatings on steel substrates using CrN interlayers and a commercially used CrN. Finally, a bare steel insert was used as a reference sample in order to monitor the influence of the coatings. The as-deposited diamond displayed good quality polycrystalline diamond surface. After 500 injection cycles, the surface of the inserts did not show any signs of detectable degradation. The moulded objects with the diamond coating demonstrated superior dimensional performance, nevertheless, the coated samples displayed a more tarnished surface than those obtained using bare steel or the CrN finished inserts.

We report a template technique for the fabrication of high density nanocrystalline diamond (NCD)-coated silica ( a -SiO 2 ) nanofibers with diameters of 1–5 μm. This method includes the synthesis of templates ( a -SiO 2 nanofibers) by conventional Vapor–Liquid–Solid method and the conformal coating of the nanofibers with nanodiamond by Microwave Plasma Chemical Vapor Deposition technique in hydrogen-deficient conditions. A detailed micro-structural analysis was performed to probe the interaction of the NCD grains with a -SiO 2 nanofibers. The specimen for Transmission Electron Microscopy was prepared using Focused Ion Beam lift-out method. Room temperature micro-Raman was performed to study the crystalline quality of the NCD-coated silica nanofibers. Field electron emission of as-synthesized NCD-coated silica nanofibers was observed with a threshold field of ~ 3 V/µm.