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This study has examined the effectiveness of characteristically different cement kiln dusts (CKDs) as a partial replacement for the ground granulated blastfurnace slag (GGBFS) in the development and production of three types of blastfurnace cements (CEM III/A, B, C) according to the standard EN 197-1.27 CEM III cement blends, 9 blends per type of cement, i.e., CEM III/A, CEM III/B and CEM III/C, were prepared in the laboratory mill from industrial starting materials (Portland cement clinker, gypsum, GGBFS, CKDs). The addition of gypsum as the setting regulator was fixed at 4 mass % in all blends studied. The content of both CKDs (cement clinker dust and cement filter dust) as slag replacements was 4 mass % in all CKD blends studied. The ordinary Portland cement (OPC) type CEM I 42.5N was used as the control cement. The results have shown that the chemical composition and chemical and physical properties of prepared CEM III/A, B, C cement blends meet the EN 197-1 requirements. Strength development in these cement blends is obviously related to the Portland cement clinker-to-GGBFS ratio. When compared to OPC, the blastfurnace cement developed lower compressive strength at early ages, but equal or higher at later ages in more cases, i.e., all 9 CEM III/A and 7 CEM III/B cement blends meet, while no CEM III/C cement blend meets the EN 197-1 requirements for standard compressive strength Class 42.5N. From the perspective of strength, the presence of the cement clinker dust is more effective than that of the cement filter dust due to their different chemical and mineralogical compositions.

The production of chicken eggs on a widespread industrial level has led to the generation of a large amount of egg shells. These egg shells are considered to be bio-hazardous waste materials although they are a rich source of amino acids and minerals. In the present investigation, effort has been made to incorporate waste poultry egg shell particles (ESP) both in carbonized (C) as well as uncarbonized (UC) form into the matrix of an Aluminum-Silicon (Al-Si) alloy to improve its mechanical properties. Various mechanical properties of the resulting composites such as tensile strength, modulus of elasticity, hardness, toughness, impact and compressive strengths have been determined and found to increase after the addition of the ESPs confirming that the incorporation of waste ESPs in the Al-Si matrix serve as reinforcements. The increase in mechanical properties such as the hardness (10.2% - UC, 19% - C), tensile (6.61% - UC, 10.61% - C), compressive (9.12% - UC, 63.94% - C) and impact strengths (30.07% - UC, 302.35% - C) is more pronounced in the case of carbonized ESPs. Field-Emission Scanning Electron Microscopy (FE-SEM) has been conducted to determine the compositions of the matrix materials as well as the composites.

International audience; Within the general context of the electrochemical oxygen evolution reaction of the water oxidation/electrolysis, we focus on one essential aspect of electrochemical interfaces, i.e., the comprehension of the interaction and organisation of liquid water at the (semiconductor) (110)-Co3O4 surface using density functional theory-molecular dynamics simulations. A detailed characterization of the chemical and physical properties of the aqueous interface is provided in terms of structure, dynamics, electric field, work function, and spectroscopy, as a preliminary step into the modelling of the (110)-Co3O4 aqueous surface in more relevant electrochemical conditions. The water at the aqueous B-termination is, in particular, shown more dynamical than that at the A-termination and more “undisciplined”: the water is indeed mostly an HB-acceptor with the solid, with an orientation of their dipole moments found opposite the field generated by the negative surface charge. At both aqueous interfaces, the work function is twice lower than that at the bare (non-hydroxylated) surfaces. The SFG (Sum Frequency Generation) spectroscopy is shown dominated by the water in the diffuse layer, while the SFG signal from the binding interfacial layer reflects the single orientation of water at the aqueous A-termination and the two orientations of water at the aqueous B-termination.

Zn1-xMnxO is one of the prominent materials that have attractive fundamental properties suitable for device applications that include spintronics. In the present study, aluminium co-doped Zn1-xMnxO films have been synthesized by chemical spray pyrolysis on Corning 7059 glass substrates at a constant temperature of 400 oC. The ‘Al’ composition in the layers was varied in the range, 0.0-0.07 and ‘Mn’ composition in the layers was fixed at x = 0.15. The compositional analysis shows the presence of zinc, manganese, oxygen and aluminium without any other impurities. All the films were polycrystalline and showed the hexagonal wurtzite structure of ZnO with (002) crystal plane as the preferred orientation. The film exhibited a maximum optical transmittance of > 60% and the evaluated band gap was 3.22 eV at an Al-doping level of 0.07. The highest remnant magnetization of 3.14x10-4 emu and coercive field of 464.8 Oe was observed in this study for an Al-doping of 0.07. The crystallite size, morphology, optical band gap and electrical resistivity were found to be significantly affected by changing the ‘Al’ concentration.

Here, a new, fast, and versatile method for the incorporation of colloidal quantum dots (QDs) into ionic matrices enabled by liquid-liquid diffusion is demonstrated. QDs bear a huge potential for numerous applications thanks to their unique chemical and physical properties. However, stability and processability are essential for their successful use in these applications. Incorporating QDs into a tight and chemically robust ionic matrix is one possible approach to increase both their stability and processability. With the proposed liquid-liquid diffusion-assisted crystallization (LLDC), substantially accelerated ionic crystallization of the QDs is shown, reducing the crystallization time needed by one order of magnitude. This fast process allows to incorporate even the less stable colloids including initially oil-based ligand-exchanged QDs into salt matrices. Furthermore, in a modified two-step approach, the seed-mediated LLDC provides the ability to incorporate oil-based QDs directly into ionic matrices without a prior phase transfer. Finally, making use of their processability, a proof-of-concept white light emitting diode with LLDC-based mixed QD-salt films as an excellent color-conversion layer is demonstrated. These findings suggest that the LLDC offers a robust, adaptable, and rapid technique for obtaining high quality QD-salts. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

In this work, a model-experimental feedback approach is developed and applied to fabricate high-quality, warm-white light-emitting diodes based on quantum dots (QDs) as color-conversion materials. Owing to their unique chemical and physical properties, QDs offer huge potential for lighting applications. Nevertheless, both emission stability and processability of the QDs are limited upon usage from solution. Incorporating them into a solid ionic matrix overcomes both of these drawbacks, while preserving the initial optical properties. Here borax (Na2B4O7·10H2O) is used as a host matrix because of its lower solubility and thereby reduced ionic strength in water in comparison with NaCl. This guarantees the stability of high-quality CdSe/ZnS QDs in the aqueous phase during crystallization and results in a 3.4 times higher loading amount of QDs within the borax crystals compared to NaCl. All steps from the synthesis via mixed crystal preparation to the warm-white LED preparation are verified by applying the model-experimental feedback, in which experimental data and numerical results provide feedback to each other recursively. These measures are taken to ensure a high luminous efficacy of optical radiation (LER) and a high color rendering index (CRI) of the final device as well as a correlated color temperature (CCT) comparable to an incandescent bulb. By doing so, a warm-white LED with a LER of 341 lm/Wopt, a CCT of 2720 K and a CRI of 91.1 is produced. Finally, we show that the emission stability of the QDs within the borax crystals on LEDs driven at high currents is significantly improved. These findings indicate that the proposed warm-white light-emitting diodes based on QDs-in-borax hold great promise for quality lighting. © 2015 American Chemical Society.

Fungal decay considerably affects the macroscopic mechanical properties of wood as a result of modifications and degradations in its microscopic structure. While effects on mechanical properties related to the stem direction are fairly well understood, effects on radial and tangential directions (transverse properties) are less well investigated. In the present study, changes of longitudinal elastic moduli and stiffness data in all anatomical directions of Scots pine (Pinus sylvestris) sapwood which was degraded by Gloeophyllum trabeum (brown rot) and Trametes versicolor (white rot) for up to 28 weeks have been investigated. Transverse properties were found to be much more deteriorated than the longitudinal ones. This is because of the degradation of the polymer matrix between the cellulose microfibrils, which has a strong effect on transverse stiffness. Longitudinal stiffness, on the other hand, is mainly governed by cellulose microfibrils, which are more stable agains fungal decay. G. trabeum (more active in earlywood) strongly weakens radial stiffness, whereas T. versicolor (more active in latewood) strongly reduces tangential stiffness. The data in terms of radial and tangential stiffnesses, as well as the corresponding anisotropy ratios, seem to be suitable as durability indicators of wood and even allow conclusions to be made on the degradation mechanisms of fungi.

Submitted by António Santos Silva (ssilva@lnec.pt) on 2009-09-25T15:15:35Z No. of bitstreams: 1 T.Freire-A237 full paper-Materiais 2009.pdf: 7249 bytes, checksum: 545a066a20e07fa74b17f957a2d45b0d (MD5) Approved for entry into archive by mpnunes@lnec.pt(mpnunes@lnec.pt) on 2009-10-08T11:27:40Z (GMT) No. of bitstreams: 1 T.Freire-A237 full paper-Materiais 2009.pdf: 7249 bytes, checksum: 545a066a20e07fa74b17f957a2d45b0d (MD5) Made available in DSpace on 2009-10-08T11:27:41Z (GMT). No. of bitstreams: 1 T.Freire-A237 full paper-Materiais 2009.pdf: 7249 bytes, checksum: 545a066a20e07fa74b17f957a2d45b0d (MD5) Previous issue date: 2009-04 Made available in DSpace on 2010-04-27T07:26:34Z (GMT). No. of bitstreams: 2 license.txt: 1838 bytes, checksum: 9772d38e2cd23107e941a23ec84a6a35 (MD5) T.Freire-A237 full paper-Materiais 2009.pdf: 7249 bytes, checksum: 545a066a20e07fa74b17f957a2d45b0d (MD5) Previous issue date: 2009-04 Made available in DSpace on 2014-10-20T16:32:22Z (GMT). No. of bitstreams: 2 T.Freire-A237 full paper-Materiais 2009.pdf: 7249 bytes, checksum: 545a066a20e07fa74b17f957a2d45b0d (MD5) license.txt: 1838 bytes, checksum: 9772d38e2cd23107e941a23ec84a6a35 (MD5) Previous issue date: 2009-04 Made available in DSpace on 2017-04-12T15:03:52Z (GMT). No. of bitstreams: 2 license.txt: 1838 bytes, checksum: 9772d38e2cd23107e941a23ec84a6a35 (MD5) T.Freire-A237 full paper-Materiais 2009.pdf: 7249 bytes, checksum: 545a066a20e07fa74b17f957a2d45b0d (MD5) Previous issue date: 2009-04 Teresa Freire’s PhD research study is being supported by the scholarship SFRH/BD/40128/2007 from Fundação para a Ciência e Tecnologia (FCT). The authors would also like to thank the technicians Susana Couto and Paula Menezes from Materials Department and Dora Santos, from the Buildings Department of LNEC, for their support on the execution of the experimental work. 3 4 6p DM/NMM 2009 5 a 8 de Abril

Each material has its own advantages and disadvantages in terms of its mechanical, chemical and physical properties. Metallic materials are comparatively ductile and easy to process. Fibre reinforced plastics are very stiff and endure high tensile stresses based on their weight. By intelligent combination of these materials into one overall-part light but strong components may be established. However, the conventional production of a separate fibre reinforced plastic (FRP)-component and a metal component and a subsequent joining is time- And labour-intensive and therefore not economical in mass-production. Thus in this paper a new fabrication technology is presented. German Federation of Industrial Research Associations (AiF) European Research Association for Sheet Metal Working (EFB) Federal Ministry of Economics and Technology (BMWi)