Publications by authors named "Qingrong Feng"

Graphene is a well-known material with various potential applications. Here we report the manufacture of high-quality and large-scale monolayer graphene pasters via polyvinyl butyral (PVB). These pasters have good self-supporting properties and overcome the drawback of weak mechanical strength of PMMA.

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High quality single-crystal magnesium diboride (MgB(2)) nanowires with lengths exceeding 10 μm were successfully synthesized by hybrid physical chemical vapor deposition. The magnetization and electrical transport properties of single-crystal MgB(2) nanowires (NWs) were measured. The superconducting transition temperature of the NWs was 37 K, as confirmed by magnetization measurements.

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Massive superconducting MgB(2) nanofibers are obtained for the first time from Mg(BH(4))(2). The technique optimizes reaction conditions to only 1 h at 460 °C and provides nanofibers which exhibited satisfying superconducting properties. The morphology transformation according to temperature changes and the special mechanism of precursor inductive synthesis are discussed.

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In this work, MgB(2) whiskers were fabricated on a copper substrate by using the hybrid physical-chemical vapor deposition, which was one of the most effective ways to make high quality pure MgB(2) films, with the possible growth mechanism discussed. The whiskers are hexagonal and conelike and grow along the [0001] direction with a single-crystal structure. The onset transition temperature is approximately 39 K, which is among the best in the published nanostructure MgB(2) papers.

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We have measured the normal state temperature dependence of the Hall effect and magnetoresistance in epitaxial MgB2 thin films with variable disorders characterized by the residual resistance ratio RRR ranging from 4.0 to 33.3.

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