Spectrochimica Acta Part B: Atomic Spectroscopy, 129 (2016) 1-7. doi:10.1016/j.sab.2016.12.006

There are many different ways to reduce the construction industry's impact on environment. The incorporation of waste in the fabrication of construction materials may be beneficial for both the waste management sector and the construction industry. The aim of this research was to investigate the use of three different waste materials (construction and demolition waste, brick powder and fly ash) as filler in asphalt mixtures. Limestone filler was used as reference material. The materials were characterized in terms of their geometrical, physical and chemical properties, and the interaction with bitumen was assessed with two mastic test methods using four different bitumens. The specific surface of waste materials shows a wide-ranging variation due to material specific shape and texture of particles. However, the Rigden voids and bitumen number tests adequately measure the stiffening effect of these materials. The delta ring and ball test results showed there is a good relation with the filler content when the results are affected by the bitumen type. The f/b ratio for a specific bitumen–filler combination can be determined from the maximum filler-to-bitumen ratio and the recommended stiffening increase. The mastics with these waste materials showed strong resistance to water damage.

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Germany has ambitious targets to produce 35 % of the needed electricity from Renewables (RES) mainly based on wind and solar power by 2020 and over 80 % by 2050 within the so called “Energiewende”. Energy storage is seen as a potential option to assure the safe RES system integration to achieve this goals. There is a high uncertainty and the resulting public discourse about the future demand of different storage technologies is driving further development of these technologies. A literature review of 9 studies and 10 expert interviews is carried out in line of a foresight exercise to tackle these uncertainties. The estimations of reviewed literature are based on models with a market perspective on energy storage demand. Most scenarios used in this models are built on top down logics, where processes at lower levels (technology, micro-economic sphere) are determined by dominant macro dynamics. Different storage technologies are only considered partially or in an aggregated way. The reviewed studies show that there is a high for potential storage on every time scale starting from the year 2030 to 2040. Analysed potentials vary depending on RES diffusion scenarios and excess rate assumptions which are estimated to be between 0 to 44 GW in 2050. Reviewed studies strongly integrate shared visions about system developments and formal analyses and provide important and valuable information about potential future implications regarding energy storage. But they only partially account, due to practical reasons, wider benefits, stakeholder opinions and continuous market and system changes. It is also not possible to account for discontinuities in the technological innovation process of energy storage within this quantitative approaches. Stakeholder interviews provide thus additional and helpful insights to the literature review. The stakeholders frame alternative potential future developments that could influence the market success and need for energy storage until 2050. Most important factors named where policy measures, new market models and decentralization of the energy system. As in literature there is a big uncertainty among experts about the importance of different storage technologies and if energy storage is in general the best option among other flexibility measures as grid reinforcement, flexible demand and flexible power plants. It remains thus impossible to provide suggestions regarding the development of single storage technologies.

The biological relevance of molybdenum was demonstrated in the early 1950s-1960s, by Bray, Beinert, Lowe, Massey, Palmer, Ehrenberg, Pettersson, Vänngård, Hanson and others, with ground-breaking studies performed, precisely, by electron paramagnetic resonance (EPR) spectroscopy. Those earlier studies, aimed to investigate the mammalian xanthine oxidase and avian sulfite oxidase enzymes, demonstrated the surprising biological reduction of molybdenum to the paramagnetic Mo⁵⁺. Since then, EPR spectroscopy, alongside with other spectroscopic methods and X-ray crystallography, has contributed to our present detailed knowledge about the active site structures, catalytic mechanisms and structure/activity relationships of the molybdenum-containing enzymes.
This Chapter will provide a perspective on the contribution that EPR spectroscopy has made to some selected systems. After a brief overview on molybdoenzymes, the Chapter will be focused on the EPR studies of mammalian xanthine oxidase, with a brief account on the prokaryotic aldehyde oxidoreductase, nicotinate dehydrogenase and carbon monoxide dehydrogenase, vertebrate sulfite oxidase, and prokaryotic formate dehydrogenases and nitrate reductases.

http://docentes.fct.unl.pt/lblm/files/epr_book-chap_4.pdf

Apesar da escrita ter, habitualmente, uma maior expressão no ensino da Matemática que a própria oralidade, os alunos não estão habituados a explicitar raciocínios e a utilizar linguagem matemática apropriada. A comunicação matemática escrita tem algumas particularidades que podem ser diretamente trabalhadas com os alunos. Por exemplo, a escrita ajuda os alunos a dar sentido à Matemática e a melhorar o próprio discurso. As produções dos alunos transportam informações para o professor contribuindo para a planificação e concretização da sua prática profissional. Assim, e apesar de frequentemente ser descurada, a escrita matemática pode ser trabalhada na sala de aula, em particular, com futuros professores. Este artigo reporta parte de uma experiência realizada com uma turma da Licenciatura em Educação Básica, tendo por base a resolução em grupo de um problema de Geometria e o registo escrito do processo de resolução elaborado pelos alunos. Pretendeu-se desta forma caraterizar a comunicação escrita dos alunos e identificar contributos desta para a compreensão por parte do professor dos conhecimentos dos alunos. A análise da escrita matemática dos alunos, tendo por base um conjunto de critérios previamente definidos, permitiu identificar a preferência destes pelo recurso à representação verbal, dificuldades em fundamentar adequadamente as respostas apresentadas e uma forte tendência para desvalorizar as abordagens prévias que não conduziram à resposta ao problema. Permitiu ainda identificar uma tendência para não explicitar o entendimento das questões que lhes eram colocadas. A forma como os conceitos matemáticos surgem nas repostas escritas permite identificar aspetos relevantes do conhecimento dos alunos.

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The last decades have shown an increasing amount of research into expectations of science and technology. Especially for emerging technologies, expectations held by different stakeholder are guiding the direction of research and development. In this article the results of an investigation into the expectations of specific actors regarding the development of emerging battery technology for applications in the power grid are presented. It is set up as an explorative study within the framework of Constructive Technology Assessment (CTA). A number of studies since the 1990s have indicated a growing need for energy storage options in the power grid, where batteries appear to be capable of providing a range of valuable services to the grid. Cost-effectiveness on a large scale will however require considerable technical improvements. The configuration of energy storage may differ in the specific location and exploitation of the storage assets, as well as in the investments in new storage capacity. In this study the visions and expectations of several relevant actors are analysed using interviews and surveys in terms of expectations of technological development, expectations concerning stakeholder roles, and channels of interaction between the relevant actors. The results indicate a divide in expectations between the user side of the technology (the electric power industry) and the development side (academic researchers). Opinions differ with respect to the obstacles to technological development, the actors relevant in early technological development, and the most suitable channels for interaction between these actors. It follows from the theoretical background that conflicts in expectations provide the opportunity for the acceleration of technological development and adoption through stakeholder participation. Small interactive workshops, where conflicts identified in this paper are discussed, were identified as a suitable channel in order to reach consensus in visions and expectations for battery technology.

The effect of ply thickness on the onset of intralaminar and interlaminar damage is extremely important for the structural response of laminated composite structures. This subject has gained particular interest in recent years due to the introduction in the market of spread-tow, ultra-thin carbon-fibre reinforcements with different configurations. In the present paper, an experimental test campaign was carried out to study the structural response of aerospace-grade plain weave spread-tow fabrics (STFs) of different areal weights. The results showed that, in spite of an apparent superior longitudinal tensile strength of the thick STF, the multidirectional thin-STF laminate exhibited an improved tensile unnotched strength over the thick-STF laminate, attributed to its damage suppression capability. However, damage suppression was also responsible for similar tensile notched strengths. In compression, the thin-STF laminate performed substantially better than the thick-STF laminate in both unnotched and notched configurations. Finally, a similar bearing response was obtained in both STF laminates, in spite of a slightly higher resistance of the thin-STF laminate to the propagation of subcritical damage mechanisms.

This paper presents a control process and frequency adjustment based on the Magnetic Core Reactor prototype. For the past decades, there has been significant development in the technologies used in Wireless Power Transfer systems. In the Wireless Power Transfer systems it is essential that the operating frequency of the primary circuit be equal to the resonant frequency of the secondary circuit so there is the maximum energy transfer. The Magnetic Core Reactor allows controlling of the frequencies on both sides of the transmission and reception circuits. In addition, the assembly diagrams and test results are presented.

Spectrochimica Acta Part B: Atomic Spectroscopy, 120 (2016) 30-36. doi:10.1016/j.sab.2016.03.014

The wind energy production is a growing industry and the energy produced is renewable and environmentally cleaner than most of the other systems. The towers to support the wind energy generators may be built with precast concrete elements that are competitive in comparison to other structural systems. The evolution of the technology for wind energy production shows a clear need for larger wind turbines and longer blades and, consequently, taller towers, where precast concrete solutions are competitive. Truss precast concrete towers is a solution that complies with the demands of the present and future wind energy production. The research on the execution and structural behaviour of the connections between the tower elements is an important issue. This communication presents the experimental analysis of column to column connections for precast concrete towers. The tests included connections with commercial threaded bars welded to the rebars and connections with grouted corrugated steel sleeves. Thick joints (50 mm) filled with fibre reinforced grout and thin joints (3 mm) filled with epoxy resin were tested and analysed.