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Satsumasendai, Japan

Neumeier S.,Friedrich - Alexander - University, Erlangen - Nuremberg | Pyczaky F.,Friedrich - Alexander - University, Erlangen - Nuremberg | Pyczaky F.,Institute for Materials Research | Goken M.,Friedrich - Alexander - University, Erlangen - Nuremberg
Philosophical Magazine

The effect of rhenium and ruthenium on the hardness of the γ′ precipitates and the γ matrix in nickel-base superalloys was investigated using a nanoindenting atomic force microscope. The partitioning behaviour of the alloying elements and the lattice misfit between the γ and γ′ phase were determined in fully homogenised samples to explain the alloying effects. Rhenium strongly strengthens γ as it predominantly partitions to γ and has a strong solid solution-hardening effect. Ruthenium strengthens both γ and γ′ due to a more homogeneous partitioning behaviour. Ruthenium was found to cause less partitioning of rhenium to γ. This results in a stronger increase of the γ′ hardness. The change in the nanoindentation-derived hardness of both phases could be mainly attributed to the solid solution strengthening of Re and Ru. © 2011 Taylor & Francis. Source

Velghe I.,NuTeC | Velghe I.,Hasselt University | Carleer R.,Hasselt University | Yperman J.,Hasselt University | And 2 more authors.
Water Research

Copper and zinc removal from water (pH = 5.0) using adsorbents produced from slow and fast pyrolysis of industrial sludge and industrial sludge mixed with a disposal filter cake (FC), post treated with HCl, is investigated in comparison with a commercial adsorbent F400. The results show that a pseudo-second order kinetics model is followed. The Langmuir-Freundlich isotherm model is found to fit the data best. The capacity for heavy metal removal of studied adsorbents is generally better than that of commercial F400. The dominant heavy metal removal mechanism is cation exchange. Higher heavy metal removal capacity is associated with fast pyrolysis adsorbents and sludge/FC derived adsorbents, due to enhanced cation exchange. Improvement of Zn 2+ removal via 1 N HCl post-treatment is only effective when exchangeable cations of the adsorbent are substituted with H + ions, which boost the cation exchange capacity. Increase of temperature also enhances metal removal capacity. Fast pyrolysis sludge-based adsorbents can be reused after several adsorption-desorption cycles. © 2012 Elsevier Ltd. Source

Venkataramanan N.S.,Institute for Materials Research
International Journal of Quantum Chemistry

The structure and stability for the association of water with dimethyl sulfoxide (DMSO) are investigated using the density functional M06-2X level theory. Stable complexes are formed by the formation of hydrogen bonding between water and oxygen atom of DMSO molecule, while the electrostatic force between water and DMSO plays a vital role in deciding the structure. The water-DMSO interactions are stronger than the interwater hydrogen bonds, which can be inferred from the shorter DMSO-water bond distance compared with the water-water bond distance. The calculated solvent association energy does not saturate, and it remains favorable to attach additional water molecules to the existing water network. The calculated IR spectra shifts supports the formation stronger hydrogen bonding, while the electrostatic potential (ESP) plot supports the existence of weaker electrostatic interaction in the studied clusters. The polarizabilities for the ground state clusters were found to increase monotonically with the cluster size. The presence of additional electrostatic bonding between water and DMSO, devastates the linear hydrogen-bonding network. Copyright © 2011 Wiley Periodicals, Inc. Source

De Schepper E.,Hasselt University | Van Passel S.,Hasselt University | Manca J.,Institute for Materials Research | Thewys T.,Hasselt University
Renewable Energy

In the light of global warming, renewables such as solar photovoltaics (PV) are important to decrease greenhouse gas emissions. An important issue regarding implementation of solar panels on large scale, is the limited available area. Therefore, it can be interesting to combine PV with alternative applications, as a ways of not requiring " additional" space. One example is a photovoltaic noise barrier (PVNB), where a noise barrier located along a highway or railway is used as substructure for PV modules. Even though a PVNB is not a novel concept, the absence of economic assessments in literature can be a barrier to their wider implementation.In this paper, a feasibility study of a PVNB in Belgium is conducted, using a cost benefit analysis including a Monte Carlo sensitivity analysis. Besides purely economic aspects, also ecological benefits are monetized. The sensitivity analysis indicates that the ecological benefit of noise reduction, which is valuated using a noise sensitivity depreciation index applied to real estate prices, is of major importance in determining the net present value of the case study. On the contrary, the impact of reducing CO 2 emissions seems to be negligible when expressed in monetary terms. The results suggest that the PVNB as a whole and also its separate components -i.e. the PV array and the noise barrier- can be profitable projects, when ecological benefits are included. © 2012 Elsevier Ltd. Source

Wu G.,Shanghai JiaoTong University | Teng N.-G.,Shanghai JiaoTong University | Wang Y.,Institute for Materials Research
Yantu Gongcheng Xuebao/Chinese Journal of Geotechnical Engineering

The laboratory tests are performed to study the physical and mechanical properties of Jiaozuo limestone after undergoing different high temperatures. The temperature varies in the range of 100°C, 200°C, 400°C, 600°C and 800°C. The scopes of this study include the description of apparent shape, the measurement of volume, mass and density and the detection of longitudinal wave and shear wave of limestone. The peak stress, peak strain and Young's modulus of limestone are also investigated under the uniaxial compression. The factors of degradation of limestone under high temperatures are discussed. The test results show that the high temperatures lead to variation of the apparent shape for limestone. The temperatures do not obviously affect the physical and mechanical properties of limestone below 400°C. The volume of limestone reduces slightly below 200°C, but increases obviously over 200°C. Meanwhile, the density of limestone decreases gradually with the increase of the temperatures. As the temperatures increase, the S-wave velocity and the P-wave velocity for limestone generally decrease. The variation of ratio of wave velocity for limestone is irregular after high temperature. The dynamic elastic modulus of limestone after high temperature decreases with the increase of the temperatures. When the temperature is above 400°C, the mechanical properties of limestone exhibit deterioration with the increase of the temperature, and the peak stress and Young's modulus of limestone decrease to different extents. The variation of the peak strain of limestone is unconspicuous before 800°C. The thermal stress, variations of mineral formation and microstructure due to the temperatures result in the variation of physical and mechanical properties and degradation of limestone. Source

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