36,304 research outputs found

    Tuning electronic structure of graphene via tailoring structure: theoretical study

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    Electronic structures of graphene sheet with different defective patterns are investigated, based on the first principles calculations. We find that defective patterns can tune the electronic structures of the graphene significantly. Triangle patterns give rise to strongly localized states near the Fermi level, and hexagonal patterns open up band gaps in the systems. In addition, rectangular patterns, which feature networks of graphene nanoribbons with either zigzag or armchair edges, exhibit semiconducting behaviors, where the band gap has an evident dependence on the width of the nanoribbons. For the networks of the graphene nanoribbons, some special channels for electronic transport are predicted.Comment: 5 figures, 6 page

    The solution of special squeeze film gas bearing problems by an improved numerical technique

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    Computer program for solving squeeze film gas bearing problem

    Spherical squeeze-film hybrid bearing with small steady-state radial displacement

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    Spherical squeeze-film hybrid bearing with small steady-state radial displacement analysi

    Analysis, design, and prototype development of squeeze-film bearings for AB-5 gyro Final report phase 2, design, fabrication and evaluation of prototypes

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    Squeeze-film bearing transducers with piezoceramic cylinders for AB-5 gyro - design, fabrication, and testing of cylindrical journal and annular bearing prototype

    Microphase transitions of block copolymer/homopolymer under shear flow

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    Cell dynamics simulation is used to investigate the phase behavior of block copolymer/homopolymer mixture subjected to a steady shear flow. Phase transitions occur from transverse to parallel and then to perpendicular lamellar structure with an increase of shear rate and this is the result of interaction between the shear flow and the concentration fluctuation. Rheological properties, such as normal stress differences and shear viscosity, are all closely related with the direction of the lamellae. Furthermore, we specifically explore the phase behavior and the order parameter under weak and strong shear of two different initial states, and realize the importance of the thermal history. It is necessary to apply the shear field at the appropriate time if we want to get what we want. These results provide an easy method to create ordered, defect-free materials in experiment and engineering technology through imposing shear flow.Comment: 14 pages, 9 figure
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