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Showing 1 to 16 of 16 for “"QENS"”.
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Analysis of dislocation pipe diffusion in deformed alpha-phase PdHX using a synthesized QENS approach
… indicate that the simultaneous comparison of QENS results from instrument with different instrumental resolution and energy transfer window can provide a more comprehensive picture of the diffusive modes seen within a system than using the instruments independently. A method is developed for …
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Combined computational and neutron scattering studies of hydrocarbons confined in mesoporous materials
… and Quasi Elastic Neutron Scattering (QENS) experiments are used to investigate the dynamics of industrially relevant catalysis reactions. Despite the widespread industrial applications of mesoporous materials there is often little understanding of the dynamical processes within the …
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Study of slow dynamics in supercooled water by molecular dynamics and quasi-elastic neutron scattering
… by quasi-elastic neutron scattering (QENS) and molecular dynamics (MD) simulation results. The dynamics of supercooled water can be decoupled into a product of translational and rotational dynamics. While the translational dynamics is modelled well by a product of a ISF representing …
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Studies on hydration water dynamics and microstructure of synthetic cement
… quasi-elastic neutron scattering (QENS). C-S-H and M-S-H are the chemical binders present in calcium rich and magnesium rich cement. To analyze the cement QENS data, we developed a new global model which is numerically more stable than previous models for cement QENS analysis. With …
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Monte-Carlo Simulation of Diffusion as an Aid to Interpreting Quasi-elastic Neutron Scattering from Lattice Gas Systems with Diffusion on Multiple Time-Scales
… is provided by quasi-elastic neutron scattering (QENS); the timescales that can be observed are dependent on the energy range and resolution of the instru- mentation. Historical QENS measurements of PdH have been interpreted in terms of single process involving nearest-neighbour jumps between …
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Ab initio modeling of hydrogen pipe diffusion in palladium
… Specifically, quasielastic neutron scattering (QENS) experiments, for the first time, directly measured hydrogen pipe diffusion. The diffusivities and energy barriers from ab initio simulations support these findings, but open questions remain, the most concerning of which pertains to the …
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Simulation studies of slow dynamics of hydration water in lysozyme : hydration level dependence and comparison with experiment using new time domain analysis
… (ISF) from Quasi-Elastic Neutron Scattering (QENS) experiments from frequency domain to time domain. Then, the Relaxing-Cage Model (RCM) fitting is performed on the converted ISF in time domain. The average translational relaxation time of the MD simulation is compared with the QENS …
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Dynamics Of Biopolymers On Nanomaterials Studied By Quasielastic Neutron Scattering And Mdsimulations
… two tools, quasielastic neutron scattering (QENS) and Molecular Dynamics Simulations to probe the effect of ND on RNA dynamics. Our work provides fundamental understanding of how hydrated RNA motions are affected in the RNA-ND nanocomposites. From the experimental and Molecular Dynamics …
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Neutron scattering studies of water diffusion near the interface of model cell membranes
… (AFM) and quasielastic neutron scattering (QENS), respectively. QENS measurements on SSLBs comprised of zwitterionic (DMPC) and anionic (DMPG) lipids reveal vastly different freezing/melting behavior of their hydration water, while also elucidating various types of membrane-associated water …
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Dynamics of biopolymers and their hydration water studied by neutron and X-ray scattering
… (ENS) and quasielastic neutron scattering (QENS). We observe a fragile-to-strong crossover phenomenon at the temperature TL in supercooled water confined in substrates with different hydrophilicity and geometry. We find that water confined in hydrophobic double wall carbon nanotubes (DWNT) …
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Strukturanalyse und Segmentdynamik von Diblockcopolymer-Homopolymer-Mischungen
… Die <br>Segmentdynamik wurde mit Hilfe von QENS (Rückstreuspektrometer) <br>untersucht. Die Zugabe des Homopolymeren führte zu einem Übergang von <br>sphärischen Mizellen, die sich <br>auf einem bcc--Gitter anordneten, zu einer 2D hexagonalen Zylinderstruktur. <br>Bei der Segmentdynamik …
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Gravimetric, neutron scattering and computational studies of the sorption and diffusion of gases in zeolites
… incoherent quasi-elastic neutron scattering (QENS). For the water molecules, it was possible to distinguish three distinct modes of motion: a fast short-range component within the zeolite cage, a slower long-range component and a rotational component. The rotational component was found to be …
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Machine Learning-aided High-throughput Synthesis and Development of Optoelectronic Materials
… Next, I use Quasi-Elastic Neutron Scattering (QENS) to identify the dynamics of the multiple cations in state-of-art perovskite solar cell compositions as a function of bromine incorporation. I find that the suppression of one of the cations, FA, correlates with an increased carrier lifetime. I …
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Synthesis and Blend Behaviour of Multi-End Capped Polyethylene
… (SANS) and quasi-elastic neutron scattering (QENS) and studies proved surface enrichment with fluoro-chain ends. This work has shown that blends of fluoro-polymer preferentially segregate to the air surface interface and the subsequent surface free energies of these blends were near that of …
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Polymer Structure and Dynamics in Nano-Confinements: Polymer Nanocomposiets and Cylindrical Confinement
… confinement are measured experimentally using QENS. When polystyrene is confined in cylindrical nanopores, the segmental relaxations slow down non-monotonically with pore size. This trend is also observed for EISF, which measured the fraction of non-diffusing hydrogen within the probing time …
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Studies of hydrogen bonding in protonic ionic liquids and their binary mixtures
… evaluated by quasi-elastic neutron scattering (QENS), collected at ISIS Rutherford Appleton Laboratories. The results reported here suggest that a jump diffusional model accurately represents its molecular motion.<br/><br/>This thesis reports, for the first time, the actual hydrogen bond …