The Experts below are selected from a list of 25341 Experts worldwide ranked by ideXlab platform

Alamgir Karim - One of the best experts on this subject based on the ideXlab platform.

  • orientational Order in block copolymer films zone annealed below the Order disOrder Transition temperature
    Nano Letters, 2007
    Co-Authors: Brian C Berry, August W Bosse, Jack F Douglas, Ronald L Jones, Alamgir Karim
    Abstract:

    We report measurements of rapid Ordering and preferential alignment in block copolymer films zone annealed below the Order−disOrder Transition temperature. The orientational correlation lengths measured after approximately 5 h above the glass-Transition temperature (≈ 2 μm) were an Order of magnitude greater than that obtained under equivalent static annealing. The ability to rapidly process polymers with inaccessible Order−disOrder Transition temperatures suggests zone annealing as a route toward more robust nanomanufacturing methods based on block copolymer self-assembly.

  • orientational Order in block copolymer films zone annealed below the Order disOrder Transition temperature
    Nano Letters, 2007
    Co-Authors: Brian C Berry, August W Bosse, Jack F Douglas, Ronald L Jones, Alamgir Karim
    Abstract:

    We report measurements of rapid Ordering and preferential alignment in block copolymer films zone annealed below the Order-disOrder Transition temperature. The orientational correlation lengths measured after approximately 5 h above the glass-Transition temperature ( approximately 2 microm) were an Order of magnitude greater than that obtained under equivalent static annealing. The ability to rapidly process polymers with inaccessible Order-disOrder Transition temperatures suggests zone annealing as a route toward more robust nanomanufacturing methods based on block copolymer self-assembly.

Jian Luo - One of the best experts on this subject based on the ideXlab platform.

  • single phase duodenary high entropy fluorite pyrochlore oxides with an Order disOrder Transition
    Acta Materialia, 2021
    Co-Authors: Andrew Wright, Qingyang Wang, Yiting Yeh, Renkun Chen, Jian Luo
    Abstract:

    Abstract Improved thermomechanical properties have been reported for various high-entropy oxides containing typically five metal cations. This study further investigates a series of duodenary (11 metals + oxygen) high-entropy oxides by mixing different fractions of a five-cation fluorite-structured niobate and a seven-cation pyrochlore (both containing Yb) with matching lattice constants. Nine compositions of duodenary high-entropy oxides have been examined. All of them exhibit single high-entropy phases of either disOrdered fluorite or Ordered pyrochlore structure. An Order-disOrder Transition (ODT) is evident with changing composition, accompanied by a reduction in thermal conductivity ( k ). In comparison with the ODT criteria developed from ternary oxides, these duodenary oxides are more prone to disOrder, but the ODT is still controlled by similar factors (but at different thresholds). Interestingly, there are abrupt increases in Young's modulus ( E ) at low mixing concentrations near both endmembers. The E / k ratios are increased, in comparison with both endmembers. This study suggests a new route to tailor high-entropy ceramics via controlling cation Ordering vs. disOrdering.

Antonio Castro H Neto - One of the best experts on this subject based on the ideXlab platform.

  • Order disOrder Transition in a two dimensional boron carbon nitride alloy
    Nature Communications, 2013
    Co-Authors: Kai Zhang, Xinfeng Liu, Han Zhang, Tze Chien Sum, Antonio Castro H Neto, Kian Ping Loh
    Abstract:

    Two-dimensional boron-carbon-nitride materials exhibit a spectrum of electronic properties ranging from insulating to semimetallic, depending on their composition and geometry. Detailed experimental insights into the phase separation and Ordering in such alloy are currently lacking. Here we report the mixing and demixing of boron-nitrogen and carbon phases on ruthenium (0001) and found that energetics for such processes are modified by the metal substrate. The brick-and-mortar patchwork observed of stoichiometrically percolated hexagonal boron-carbon-nitride domains surrounded by a network of segregated graphene nanoribbons can be described within the Blume-Emery-Griffiths model applied to a honeycomb lattice. The isostructural boron nitride and graphene assumes remarkable fluidity and can be exchanged entirely into one another by a catalytically assistant substitution. Visualizing the dynamics of phase separation at the atomic level provides the premise for enabling structural control in a two-dimensional network for broad nanotechnology applications.

  • Order disOrder Transition in a two dimensional boron carbon nitride alloy
    Nature Communications, 2013
    Co-Authors: Jiong Lu, Kai Zhang, Han Zhang, Antonio Castro H Neto
    Abstract:

    The alloying of graphene and hexagonal boron nitride results in tunable electronic properties that can be used for solid state devices. Lu et al. identify atomic-scale mechanisms of alloying boron–carbon–nitrogen on ruthenium as a model system, which allow for potentially greater control of properties.

Ashish K Khandpur - One of the best experts on this subject based on the ideXlab platform.

  • polyisoprene polystyrene diblock copolymer phase diagram near the Order disOrder Transition
    Macromolecules, 1995
    Co-Authors: Frank S. Bates, Kristoffer Almdal, Stephan Forster, Ashish K Khandpur, Ian W Hamley, Anthony J Ryan, Wim Bras, Kell Mortensen
    Abstract:

    The phase behavior of ten polyisoprene-polystyrene (PI-PS) diblock copolymers, spanning the composition range from 0.24 to 0.82 polyisoprene volume fraction (f PI ), has been studied near the Order-disOrder Transition (ODT). Dynamic mechanical spectroscopy, transmission electron microscopy, and neutron and X-ray scattering have been used to characterize phase Transition temperatures and Ordered state symmetries. Five distinct microstructures were observed for this chemical system : spheres, hexagonally packed cylinders (HEX), lamellae (LAM), hexagonally perforated layers (HPL), and a bicontinuous cubic phase having an Ia3d space group symmetry. The bicontinuous Ia3d phase only occurs in the vicinity of the ODT between the HEX and LAM states at compositions of 0.65 ≤ f pI ≤ 0.68 and 0.36 ≤ f pI ≤ 0.39 (prior report). Farther from the ODT, within these composition ranges, the HPL phase occurs. We did not find the Ordered bicontinuous double diamond (OBDD) morphology at any composition or temperature studied, and the overall phase diagram is qualitatively different from those reported previously for PI-PS block copolymers.

  • complex phase behavior of polyisoprene polystyrene diblock copolymers near the Order disOrder Transition
    Macromolecules, 1994
    Co-Authors: Stephan Forster, Ashish K Khandpur, Jin Zhao, Ian W Hamley, Anthony J Ryan, Wim Bras
    Abstract:

    The phase behavior of polyisoprene-polystyrene (PI-PS) diblock copolymers near the Order disOrder Transition was investigated using dynamic mechanical measurements, TEM, SAXS and SANS at polyisoprene volume fractions 0.33< F PI < 0.42. Two new Ordered morphologies have been documented between hexagonally packed cylinders (HEX) and lamellae (LAM). At low temperatures a hexagonally perforated layered (HPL) microstructure occurs, that transforms into a bicontinuous cubic phase characterized by Ia3d space group symmetry near the Order disOrder Transition (ODT). The Ordered-bicontinuous double diamind (OBDD) phase was not found at any temperature or composition studied

Brian C Berry - One of the best experts on this subject based on the ideXlab platform.

  • orientational Order in block copolymer films zone annealed below the Order disOrder Transition temperature
    Nano Letters, 2007
    Co-Authors: Brian C Berry, August W Bosse, Jack F Douglas, Ronald L Jones, Alamgir Karim
    Abstract:

    We report measurements of rapid Ordering and preferential alignment in block copolymer films zone annealed below the Order−disOrder Transition temperature. The orientational correlation lengths measured after approximately 5 h above the glass-Transition temperature (≈ 2 μm) were an Order of magnitude greater than that obtained under equivalent static annealing. The ability to rapidly process polymers with inaccessible Order−disOrder Transition temperatures suggests zone annealing as a route toward more robust nanomanufacturing methods based on block copolymer self-assembly.

  • orientational Order in block copolymer films zone annealed below the Order disOrder Transition temperature
    Nano Letters, 2007
    Co-Authors: Brian C Berry, August W Bosse, Jack F Douglas, Ronald L Jones, Alamgir Karim
    Abstract:

    We report measurements of rapid Ordering and preferential alignment in block copolymer films zone annealed below the Order-disOrder Transition temperature. The orientational correlation lengths measured after approximately 5 h above the glass-Transition temperature ( approximately 2 microm) were an Order of magnitude greater than that obtained under equivalent static annealing. The ability to rapidly process polymers with inaccessible Order-disOrder Transition temperatures suggests zone annealing as a route toward more robust nanomanufacturing methods based on block copolymer self-assembly.