Cobalt-based alloys are widely used as hardfacing materials when wear resistance is required at room temperature or high temperature applications. However, their performance is a consequence of their microstructures t...
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Cobalt-based alloys are widely used as hardfacing materials when wear resistance is required at room temperature or high temperature applications. However, their performance is a consequence of their microstructures that depends on the processing conditions. This work focused on the influence of solidification rate on the structure development by processing the alloys with and without the interference of the substrate. The coatings were characterized by scanning electron microscopy, energy dispersive spectrometer, optical microscopy and instrument indentation tests. Results showed that despite the same phases developed in tested conditions, differences in the solidification microstructure and the influence of Fe diffusing from the substrate accounted for the measured variation in hardness. Higher hardness values were obtained for the samples processed free-standing (mini billets) with respect to the coatings and they were independent of the processing parameters, indicating that the substrate compromise the properties of hardness, as expected.
Using chemical vapor deposition technique, a novel 3D carbon nano-architecture called a pillared graphene nanostructure (PGN) is in situ synthesized. The fabricated novel carbon nanostructure consists of CNT pillars o...
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Combinatorial phage display with a pVIII library of M13 bacteriophage was used to identify a peptide sequence capable of recognition and mineralization of copper sulfide. The six sequences isolated from the final biop...
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Combinatorial phage display with a pVIII library of M13 bacteriophage was used to identify a peptide sequence capable of recognition and mineralization of copper sulfide. The six sequences isolated from the final biopanning round were rich in basic, hydrophobic, and polar amino acids compared to the phage display library. The peptide sequence, DTRAPEIV, was used to biomineralize copper sulfide on the pVIII major coat protein thus producing linear chains of nanoparticles. Electron microscopy revealed that the phage was capable of controlling the size of the nucleated nanoparticles in an aqueous solution at room temperature and that the mineralized material was copper sulfide. Phage-templated biomineralization is a low temperature, aqueous-based approach to synthesis of copper sulfide nanoparticles with hierarchical order.
The unique structure and properties of graphene initiated broad fundamental and technological research, and highlighted graphene as a new candidate for various applications such as energy storage, solar cells and elec...
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The unique structure and properties of graphene initiated broad fundamental and technological research, and highlighted graphene as a new candidate for various applications such as energy storage, solar cells and electronic devices. Chemical vapor deposition (CVD) has been utilized for industrial large-scale synthesis of graphene. Regardless of the synthesis process, graphene should be transferred to arbitrary substrates for different applications. The transfer processes, introduce defects such as wrinkles and cracks in graphene which compromise the properties and applications. In recent years, fundamental research has been focused on characterization of graphene to develop new techniques for large-scale, high-resolution graphene metrology. Herein, a complementary high throughput metrology technique using fluorescent quenching is further investigated for different fluorescent dyes to characterize CVD synthesized graphene.
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