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Dang Z.-M.,University of Science and Technology of China | Dang Z.-M.,Beijing University of Chemical Technology | Dang Z.-M.,Xian Jiaotong University | Yuan J.-K.,Beijing University of Chemical Technology | And 5 more authors.
Progress in Materials Science | Year: 2012

There is an increasing need for high-permittivity (high-k) materials due to rapid development of electrical/electronic industry. It is well-known that single composition materials cannot meet the high-k need. The combination of dissimilar materials is expected to be an effective way to fabricate composites with high-k, especial for high-k polymer-matrix composites (PMC). This review paper focuses on the important role and challenges of high-k PMC in new technologies. The use of different materials in the PMC creates interfaces which have a crucial effect on final dielectric properties. Therefore it is necessary to understand dielectric properties and processing need before the high-k PMC can be made and applied commercially. Theoretical models for increasing dielectric permittivity are summarized and are used to explain the behavior of dielectric properties. The effects of fillers, fabrication processes and the nature of the interfaces between fillers and polymers are discussed. Potential applications of high-k PMC are also discussed. © 2011 Elsevier Ltd. All rights reserved. Source

Lukoshko E.,Warsaw University of Technology | Mutelet F.,CNRS Reactions and Process Engineering Laboratory | Domanska U.,Warsaw University of Technology | Domanska U.,University of KwaZulu - Natal
Journal of Chemical Thermodynamics | Year: 2015

Activity coefficients at infinite dilution (γ1,28) for 35 solutes in two new tricyanomethanide containing Ionic Liquids were measured by inverse gas chromatography at temperatures from (318.15 to 368.15) K. Most organic compounds have stronger affinity with 1-butyl-4-methylpyridinium tricyanomethanide than 1-butyl-3-methylimidazolium tricyanomethanide. The retention data were further converted to gas-to-IL and analyzed using the Abraham solvation parameter model. The LSER treatment indicates that the most dominant interaction constants for this family of ILs are strong dipolarity, hydrogen bond basicity and acidity. Quantum chemical gas phase DFT calculations were performed on isolated ion pairs at the 6-311 ++ G(d,p) level basis. It was found that the stacking structure of cation and anion is compact in the [BMIM][TCM] system and relatively loose in the [BMPY][TCM] system allowing a facile restructuring of the ionic liquid [BMPY][TCM] in the process of organic compounds dissolution. © 2015 Elsevier Ltd All rights reserved. Source

Yu H.,Nagaoka University of Technology | Kobayashi T.,Nagaoka University of Technology | Hu G.-H.,CNRS Reactions and Process Engineering Laboratory
Polymer | Year: 2011

Using a bromo-terminated poly(ethylene oxide) as a macroinitiator, an amphiphilic liquid-crystalline (LC) diblock copolymer with an azobenzene moiety as a nematic mesogen was prepared by an atom transfer radical polymerization process. In thin films of the well-defined diblock copolymer with the mesogenic block as a continuous phase upon microphase separation, the influence of supramolecular cooperative motion on the microphase-separated nanocylinders was systematically studied. Although the major phase of the hydrophobic nematic LC block showed only one-dimensional order, it could endow the separated minor phase of the hydrophilic PEO nanocylinders with three-dimensionally ordered structures. Both out-of-plane perpendicular and in-plane parallel patternings of the regularly ordered nanocylinder arrays were successfully fabricated on macroscopic scales by thermal annealing and photoalignment, respectively. The microphase-separated nanostructures with high regularity showed excellent reproducibility and mass production, which might guarantee nanotemplated fabrication processes and would lead to novel industrial applications in macromolecular engineering. © 2011 Elsevier Ltd. Source

Berendonk T.U.,TU Dresden | Manaia C.M.,Catholic University of Portugal | Merlin C.,CNRS Laboratory of Physical Chemistry and Microbiology for the Environment | Fatta-Kassinos D.,University of Cyprus | And 13 more authors.
Nature Reviews Microbiology | Year: 2015

Antibiotic resistance is a threat to human and animal health worldwide, and key measures are required to reduce the risks posed by antibiotic resistance genes that occur in the environment. These measures include the identification of critical points of control, the development of reliable surveillance and risk assessment procedures, and the implementation of technological solutions that can prevent environmental contamination with antibiotic resistant bacteria and genes. In this Opinion article, we discuss the main knowledge gaps, the future research needs and the policy and management options that should be prioritized to tackle antibiotic resistance in the environment. © 2015 Macmillan Publishers Limited. All rights reserved. Source

Taniere A.,CNRS Mechanical Energy, Theories, and Applications Laboratory | Arcen B.,CNRS Reactions and Process Engineering Laboratory
International Journal of Multiphase Flow | Year: 2014

Nowadays, two families of stochastic models are mainly used to predict the dispersion of inertial particles in inhomogeneous turbulent flows. This first one is named "normalized model" and the second one "Generalized Langevin Model (GLM)". Nevertheless, the main differences between the normalized and GLM models have not been thoroughly investigated. Is there a model which is more suitable to predict the particle dispersion in inhomogeneous turbulence? We propose in the present study to clarify this point by computing a particle-laden turbulent channel flow using a GLM-type model, and also a normalized-type model. Particle statistics (such as concentration, mean and rms particle velocity, fluid-particle velocity covariances) will be provided and compared to Direct Numerical Simulation (DNS) data in order to assess the performance of both dispersion models. It will be shown that the normalized dispersion model studied can predict correctly the effect of particle inertia on some dispersion statistics, but not on all. For instance, it was found that the prediction of the particle kinetic shear stress and some components of the fluid-particle covariance is not physically acceptable. © 2013 Elsevier Ltd. Source

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