The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform

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

  • thermal degradation of phenolic resin silica hybrid Ceramers
    Polymer Degradation and Stability, 2000
    Co-Authors: Jiamin Lin, Chenchi M
    Abstract:

    Abstract The kinetic parameters and the structural change of thermal degradation of phenolic resin/silica hybrid Ceramers with different mixing ratios were investigated. The activation energies of thermal degradation were calculated by the methods of Kissinger, Friedman and Ozawa from a conventional dynamic thermogravimetric measurement in nitrogen atmosphere at several different heating rates. Both pure phenolic resin and hybrid Ceramers show two stages of degradation; however, the activation energies of thermal degradation of the Ceramers in the first stage are all lower than that of phenolic resin. FT–IR spectra show that the formation of silica network structure was restricted by intermolecular hydrogen bonding at lower temperature. However, the restriction disappears when the phenolic resin starts to degrade at high temperature. TGA/MS investigations show that the presence of sol–gel silica causes some changes in the degradation mechanism of the hybrid Ceramers.

Robert Schober - One of the best experts on this subject based on the ideXlab platform.

  • bounds on distance estimation via diffusive molecular communication
    Global Communications Conference, 2014
    Co-Authors: Adam Noel, Karen C. Cheung, Robert Schober
    Abstract:

    This paper studies distance estimation for diffusive molecular communication. The strength of the channel impulse response generally decreases with distance, so it is measured to estimate the distance. The Cramer-Rao lower bound on the variance of the distance estimation error is derived. The lower bound is derived for a physically unbounded environment with molecule degradation and steady uniform flow. The maximum likelihood distance estimator is derived and its accuracy is shown via simulation to perform very close to the Cramer-Rao lower bound. An existing protocol is shown to be equivalent to the maximum likelihood distance estimator if only one observation is made. Simulation results also show the accuracy of existing protocols with respect to the Cramer-Rao lower bound.

  • Bounds on Distance Estimation via Diffusive Molecular Communication
    2014 IEEE Global Communications Conference, 2014
    Co-Authors: Adam Noel, Karen C. Cheung, Robert Schober
    Abstract:

    This paper studies distance estimation for diffusive molecular communication. The Cramer-Rao lower bound on the variance of the distance estimation error is derived. The lower bound is derived for a physically unbounded environment with molecule degradation and steady uniform flow. The maximum likelihood distance estimator is derived and its accuracy is shown via simulation to perform very close to the Cramer-Rao lower bound. An existing protocol is shown to be equivalent to the maximum likelihood distance estimator if only one observation is made. Simulation results also show the accuracy of existing protocols with respect to the Cramer-Rao lower bound.

Jiamin Lin - One of the best experts on this subject based on the ideXlab platform.

  • thermal degradation of phenolic resin silica hybrid Ceramers
    Polymer Degradation and Stability, 2000
    Co-Authors: Jiamin Lin, Chenchi M
    Abstract:

    Abstract The kinetic parameters and the structural change of thermal degradation of phenolic resin/silica hybrid Ceramers with different mixing ratios were investigated. The activation energies of thermal degradation were calculated by the methods of Kissinger, Friedman and Ozawa from a conventional dynamic thermogravimetric measurement in nitrogen atmosphere at several different heating rates. Both pure phenolic resin and hybrid Ceramers show two stages of degradation; however, the activation energies of thermal degradation of the Ceramers in the first stage are all lower than that of phenolic resin. FT–IR spectra show that the formation of silica network structure was restricted by intermolecular hydrogen bonding at lower temperature. However, the restriction disappears when the phenolic resin starts to degrade at high temperature. TGA/MS investigations show that the presence of sol–gel silica causes some changes in the degradation mechanism of the hybrid Ceramers.

Lloyd H Hihara - One of the best experts on this subject based on the ideXlab platform.

  • effect of inorganic constituent on nanomechanical and tribological properties of polymer quasi ceramic and hybrid coatings
    Surface & Coatings Technology, 2012
    Co-Authors: Atul Tiwari, Lloyd H Hihara
    Abstract:

    Abstract This study investigates the variations in nanomechanical properties of coatings made of a pristine polymeric backbone and those containing silicone segments. Four different coatings with varying degrees of inorganic segments were prepared and analyzed. The four coatings were 1) a pure epoxy polymer coating, 2) a hybrid coating consisting of epoxy and silicone, 3) a Ceramer coating consisting of organo-silicone and 4) a quasi-ceramic coating consisting of specialty silicone composition. The molecular bonding characteristics of the coatings were characterized with FTIR spectroscopy. The coatings were also tested using nanoindentation and nanoscratch methods to investigate mechanical and tribological properties. The scratched surface was investigated using scanning electron microscopy and atomic force microscopy. The hybrid coating displayed superior nanomechanical properties compared to the pure polymer coating, and the coating containing high silicone levels displayed better hardness. Atomic force microscopy showed that the epoxy-based polymer coating consisted of a smooth surface that was compressed when scratched using a nanoindenter. The hybrid coating had rough surface that was damaged and partially recovered after the scratch test. The Ceramer and quasi-ceramic coatings displayed brittle failure.

V N Lariccia - One of the best experts on this subject based on the ideXlab platform.