The Experts below are selected from a list of 115857 Experts worldwide ranked by ideXlab platform

Jonathan F. Stebbins - One of the best experts on this subject based on the ideXlab platform.

  • Glass Structure melt Structure and dynamics some concepts for petrology
    American Mineralogist, 2016
    Co-Authors: Jonathan F. Stebbins
    Abstract:

    ![Figure][1] The thermodynamic and transport properties of the aluminosilicate melts at the heart of most magmatic processes vary in complex ways with composition, temperature, and pressure. Insights into these properties can come from information on the Structure of the melts themselves, and more commonly from their Glassy, quenched equivalents. Although most such connections remain qualitative or semi-quantitative, they are fundamentally important in interpretation of observations on igneous systems in nature and the laboratory, and in the formulation of physically accurate models. This review presents some of the important concepts of aluminosilicate Glass and melt Structure and dynamics that are most relevant to furthering our understanding of the igneous processes so central to how our planet has formed and evolved. The relationships among Glasses, melts, and crystals are introduced. The structural underpinnings of temperature and pressure effects on melt free energies, densities, and viscosities, constraints on the extent of order/disorder among cations and anions in melts, why silica activity varies so strongly with composition, and how liquid-liquid phase separation can be understood, are discussed. Some simple, but useful, general views are presented on melt disorder and the shapes of liquidus surfaces (key to magmatic phase equilibria), as are links between atomic-scale dynamics and viscous flow and diffusion. [1]: pending:yes

  • Effects of UV cure on Glass Structure and fracture properties of nanoporous carbon-doped oxide thin films
    Journal of Applied Physics, 2008
    Co-Authors: David M. Gage, Jonathan F. Stebbins, Luming Peng, Zhenjiang Cui, Amir Al-bayati, Kenneth P. Macwilliams, Hichem M'saad, Reinhold H. Dauskardt
    Abstract:

    The effects of UV radiation curing on the Glass Structure and fracture properties were examined for a class of nanoporous organosilicate low dielectric constant films. A detailed characterization by nuclear magnetic resonance spectroscopy and Fourier transform infrared spectroscopy showed significant changes in the Glass Structure with increasing curing time, marked by the removal of terminal organic groups and increased network-forming bonds following the initial removal of porogen material. The higher degree of film connectivity brought about by an increased cure duration is demonstrated to significantly enhance adhesive fracture properties and to moderately improve cohesive fracture resistance. Explanations for the enhanced fracture behavior are considered in terms of the Glass Structure. The important role of crack path selection during adhesive and cohesive fracture processes is used to rationalize the observed behavior.

  • UV Curing Effects on Glass Structure and Mechanical Properties of Organosilicate Low-k Thin Films
    2006 International Interconnect Technology Conference, 2006
    Co-Authors: David M. Gage, Jonathan F. Stebbins, Zhenjiang Cui, Amir Al-bayati, Kenneth P. Macwilliams, Eric P. Guyer, Alexandros T. Demos, Reinhold H. Dauskardt
    Abstract:

    Ultra-violet radiation curing has emerged as a promising technique for enhancing the Glass Structure and mechanical properties of low-k organosilicate thin films. The present work examines the effects of UV curing on the adhesive and cohesive fracture properties of carbon-doped oxide low-k films. Detailed 29Si and 13C nuclear magnetic resonance spectroscopy was employed to study the effects of UV curing on Glass Structure. The UV curing process is demonstrated to improve the Glass network by decreasing the number of terminal non-bridging bonds and increasing the number of cross-linking bonds, leading to significant increases in elastic modulus and interfacial fracture energy. However, an interesting finding is that UV curing does not lead to similar improvements in the films' cohesive strength or their resistance to environmentally assisted cracking in chemical environments. Possible mechanisms responsible for this unexpected behavior are discussed

Reinhold H. Dauskardt - One of the best experts on this subject based on the ideXlab platform.

  • Effects of UV cure on Glass Structure and fracture properties of nanoporous carbon-doped oxide thin films
    Journal of Applied Physics, 2008
    Co-Authors: David M. Gage, Jonathan F. Stebbins, Luming Peng, Zhenjiang Cui, Amir Al-bayati, Kenneth P. Macwilliams, Hichem M'saad, Reinhold H. Dauskardt
    Abstract:

    The effects of UV radiation curing on the Glass Structure and fracture properties were examined for a class of nanoporous organosilicate low dielectric constant films. A detailed characterization by nuclear magnetic resonance spectroscopy and Fourier transform infrared spectroscopy showed significant changes in the Glass Structure with increasing curing time, marked by the removal of terminal organic groups and increased network-forming bonds following the initial removal of porogen material. The higher degree of film connectivity brought about by an increased cure duration is demonstrated to significantly enhance adhesive fracture properties and to moderately improve cohesive fracture resistance. Explanations for the enhanced fracture behavior are considered in terms of the Glass Structure. The important role of crack path selection during adhesive and cohesive fracture processes is used to rationalize the observed behavior.

  • UV Curing Effects on Glass Structure and Mechanical Properties of Organosilicate Low-k Thin Films
    2006 International Interconnect Technology Conference, 2006
    Co-Authors: David M. Gage, Jonathan F. Stebbins, Zhenjiang Cui, Amir Al-bayati, Kenneth P. Macwilliams, Eric P. Guyer, Alexandros T. Demos, Reinhold H. Dauskardt
    Abstract:

    Ultra-violet radiation curing has emerged as a promising technique for enhancing the Glass Structure and mechanical properties of low-k organosilicate thin films. The present work examines the effects of UV curing on the adhesive and cohesive fracture properties of carbon-doped oxide low-k films. Detailed 29Si and 13C nuclear magnetic resonance spectroscopy was employed to study the effects of UV curing on Glass Structure. The UV curing process is demonstrated to improve the Glass network by decreasing the number of terminal non-bridging bonds and increasing the number of cross-linking bonds, leading to significant increases in elastic modulus and interfacial fracture energy. However, an interesting finding is that UV curing does not lead to similar improvements in the films' cohesive strength or their resistance to environmentally assisted cracking in chemical environments. Possible mechanisms responsible for this unexpected behavior are discussed

David M. Gage - One of the best experts on this subject based on the ideXlab platform.

  • Effects of UV cure on Glass Structure and fracture properties of nanoporous carbon-doped oxide thin films
    Journal of Applied Physics, 2008
    Co-Authors: David M. Gage, Jonathan F. Stebbins, Luming Peng, Zhenjiang Cui, Amir Al-bayati, Kenneth P. Macwilliams, Hichem M'saad, Reinhold H. Dauskardt
    Abstract:

    The effects of UV radiation curing on the Glass Structure and fracture properties were examined for a class of nanoporous organosilicate low dielectric constant films. A detailed characterization by nuclear magnetic resonance spectroscopy and Fourier transform infrared spectroscopy showed significant changes in the Glass Structure with increasing curing time, marked by the removal of terminal organic groups and increased network-forming bonds following the initial removal of porogen material. The higher degree of film connectivity brought about by an increased cure duration is demonstrated to significantly enhance adhesive fracture properties and to moderately improve cohesive fracture resistance. Explanations for the enhanced fracture behavior are considered in terms of the Glass Structure. The important role of crack path selection during adhesive and cohesive fracture processes is used to rationalize the observed behavior.

  • UV Curing Effects on Glass Structure and Mechanical Properties of Organosilicate Low-k Thin Films
    2006 International Interconnect Technology Conference, 2006
    Co-Authors: David M. Gage, Jonathan F. Stebbins, Zhenjiang Cui, Amir Al-bayati, Kenneth P. Macwilliams, Eric P. Guyer, Alexandros T. Demos, Reinhold H. Dauskardt
    Abstract:

    Ultra-violet radiation curing has emerged as a promising technique for enhancing the Glass Structure and mechanical properties of low-k organosilicate thin films. The present work examines the effects of UV curing on the adhesive and cohesive fracture properties of carbon-doped oxide low-k films. Detailed 29Si and 13C nuclear magnetic resonance spectroscopy was employed to study the effects of UV curing on Glass Structure. The UV curing process is demonstrated to improve the Glass network by decreasing the number of terminal non-bridging bonds and increasing the number of cross-linking bonds, leading to significant increases in elastic modulus and interfacial fracture energy. However, an interesting finding is that UV curing does not lead to similar improvements in the films' cohesive strength or their resistance to environmentally assisted cracking in chemical environments. Possible mechanisms responsible for this unexpected behavior are discussed

Philippe Thomas - One of the best experts on this subject based on the ideXlab platform.

  • Atomistic simulations of TeO2-based Glasses: interatomic potentials and molecular dynamics
    Physical Chemistry Chemical Physics, 2014
    Co-Authors: Anastasia Gulenko, Olivier Masson, Abid Berghout, David Hamani, Philippe Thomas
    Abstract:

    In this work we present for the first time empirical interatomic potentials that are able to reproduce TeO2-based systems. Using these potentials in classical molecular dynamics simulations, we obtained first results for the pure TeO2 Glass Structure model. The calculated pair distribution function is in good agreement with the experimental one, which indicates a realistic Glass Structure model. We investigated the short- and medium-range TeO2 Glass Structures. The local environment of the Te atom strongly varies, so that the Glass Structure model has a broad Q polyhedral distribution. The Glass network is described as weakly connected with a large number of terminal oxygen atoms.

  • Impact of tellurite-based Glass Structure on Raman gain
    Chemical Physics Letters, 2012
    Co-Authors: Guillaume Guery, Alexandre Fargues, Thierry Cardinal, Marc Dussauze, Frédéric Adamietz, Vincent Rodriguez, John David Musgraves, Kathleen Richardson, Philippe Thomas
    Abstract:

    Raman gain efficiency and Structure of tellurite Glasses in the TeO2–TaO5/2–ZnO system have been investigated by Raman and IR spectroscopies. It has been found that replacement of TaO5/2 by ZnO does not significantly modify the respective proportion of TeO4, TeO3 and TeO3+1 entities but induces an important decrease of the TeO4 structural units Raman cross section. Change of the Glass Structure at the middle range length scale is proposed to be at the origin of the large decrease of the Raman cross section of the TeO4 units.

M D Ediger - One of the best experts on this subject based on the ideXlab platform.

  • over what length scale does an inorganic substrate perturb the Structure of a Glassy organic semiconductor
    ACS Applied Materials & Interfaces, 2020
    Co-Authors: Kushal Bagchi, Camille Bishop, Michael F Toney, Chuting Deng, Nicholas E Jackson, J J De Pablo, M D Ediger
    Abstract:

    While the bulk Structure of vapor-deposited Glasses has been extensively studied, Structure at buried interfaces has received little attention, despite being important for organic electronic applications. To learn about Glass Structure at buried interfaces, we study the Structure of vapor-deposited Glasses of the organic semiconductor DSA-Ph (1,4-di-[4-(N,N-diphenyl)amino]styrylbenzene) as a function of film thickness; the Structure is probed with grazing incidence X-ray scattering. We deposit on silicon and gold substrates and span a film thickness range of 10-600 nm. Our experiments demonstrate that interfacial molecular packing in vapor-deposited Glasses of DSA-Ph is more disordered compared to the bulk. At a deposition temperature near room temperature, we estimate ∼8 nm near the substrate can have modified molecular packing. Molecular dynamics simulations of a coarse-grained representation of DSA-Ph reveal a similar length scale. In both the simulations and the experiments, deposition temperature controls Glass Structure beyond this interfacial layer of a few nanometers.

  • vapor deposited Glass Structure determined by deposition rate substrate temperature superposition principle
    Journal of Physical Chemistry Letters, 2019
    Co-Authors: Camille Bishop, Ankit Gujral, Michael F Toney, Lian Yu, M D Ediger
    Abstract:

    We show that deposition rate substantially affects the anisotropic Structure of thin Glassy films produced by physical vapor deposition. Itraconazole, a Glass-forming liquid crystal, was deposited ...