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In this paper, we report morphology of silicon nanowires (Si-NWs) grown on various surfaces and patterned substrates using Vapor–Liquid–Solid (VLS) and Solid–Liquid–Solid (SLS) techniques. It is observed that the growth conditions are critical in controlling the dimensions of wires in both techniques. In addition to this, it is also demonstrated that Si-NWs are essentially different grown on Si or GaAs substrates. For growth of Si-NWs by VLS, Si powder was evaporated in a tube furnace under Ar flow while substrates were kept at different temperatures. In SLS, experimental conditions were identical except that no external source was used. Si-NWs thus grown showed dependence on the flow rate of Ar gas and the temperature of the substrate. Interestingly, instead of only radial nannowires (NWs), nanobelts and tapered NWs were also grown on patterned Au-catalyzed GaAs surface. In the end, the analysis on the basis of existing theories of NW growth is presented. Optical properties of Si-NWs are also briefly discussed.

One-dimensional (1D) nanostructures are of great interest due to the promise of enhanced properties and improved device performance such as increased efficiency in solar cells by improved charge separation. There are many means of producing 1D nanostructures including chemical synthesis, lithography, template assisted growth and gas phase reaction. While all of these have their advantages and disadvantages, growth by gas phase reaction has the benefit of low cost and scalability to be used in mass production. This work outlines several of the more common growth mechanisms which utilize gas phase reactions to produce 1D nanostructures. The similarities and differences between the different mechanisms are discussed with an emphasis on the confinement of growth to 1D.

We assessed the efficiency of a hierarchical docking protocol against homology models in virtual ligand screening (VLS) studies. A low resolution model of factor X (FX) was built on a template of Trypsin molecule (PDB ID:1EB2). Afterward VLS was performed involving a hierarchical protocol, rigid body followed by flexible docking, both against model as well as an X-ray structure of FX (PDB ID:1FJS) using a smart library of 50,000 chemical compounds seeded with 9 known inhibitors of FX. The percentage enrichments of screened chemical compounds obtained both from the crystal structure and homology model of FX were compared to analyze the efficiency of the protocol. In the first 5% of the finally ranked database of the screened compounds, both against model and the X-ray structure, 67% of the inhibitors were retrieved.