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Full-Text Articles in Mechanical Engineering
Effects Of Crossflow Velocity And Transmembrane Pressure On Microfiltration Of Oil-In-Water Emulsions, Nikolai V. Priezjev, Tohid Darvishzadeh
Effects Of Crossflow Velocity And Transmembrane Pressure On Microfiltration Of Oil-In-Water Emulsions, Nikolai V. Priezjev, Tohid Darvishzadeh
Mechanical and Materials Engineering Faculty Publications
This study addresses the issue of oil removal from water using hydrophilic porous membranes. The effective separation of oil-in-water dispersions involves high flux of water through the membrane and, at the same time, high rejection rate of the oil phase. The effects of transmembrane pressure and crossflow velocity on rejection of oil droplets and thin oil films by pores of different cross-section are investigated numerically by solving the Navier-Stokes equation. We found that in the absence of crossflow, the critical transmembrane pressure, which is required for the oil droplet entry into a circular pore of a given surface hydrophilicity, agrees …
Molecular Dynamics Simulations Of Oscillatory Couette Flows With Slip Boundary Conditions, Nikolai V. Priezjev
Molecular Dynamics Simulations Of Oscillatory Couette Flows With Slip Boundary Conditions, Nikolai V. Priezjev
Mechanical and Materials Engineering Faculty Publications
The effect of interfacial slip on steady-state and time-periodic flows of monatomic liquids is investigated using non-equilibrium molecular dynamics simulations. The fluid phase is confined between atomically smooth rigid walls, and the fluid flows are induced by moving one of the walls. In steady shear flows, the slip length increases almost linearly with shear rate. We found that the velocity profiles in oscillatory flows are well described by the Stokes flow solution with the slip length that depends on the local shear rate. Interestingly, the rate dependence of the slip length obtained in steady shear flows is recovered when the …
Novel Platform Development Using Assembly Of Carbon Nanotube, Nanogold And Immobilized Rna Capture Element For Rapid, Selective Sensing Of Bacteria, Elizabeth I. Maurer, Kristen K. Comfort, Saber M. Hussain, John J. Schlager, Sharmila M. Mukhopadhyay
Novel Platform Development Using Assembly Of Carbon Nanotube, Nanogold And Immobilized Rna Capture Element For Rapid, Selective Sensing Of Bacteria, Elizabeth I. Maurer, Kristen K. Comfort, Saber M. Hussain, John J. Schlager, Sharmila M. Mukhopadhyay
Mechanical and Materials Engineering Faculty Publications
This study examines the creation of a nano-featured biosensor platform designed for the rapid and selective detection of the bacterium Escherichia coli. The foundation of this sensor is carbon nanotubes decorated with gold nanoparticles that are modified with a specific, surface adherent ribonucleiuc acid (RNA) sequence element. The multi-step sensor assembly was accomplished by growing carbon nanotubes on a graphite substrate, the direct synthesis of gold nanoparticles on the nanotube surface, and the attachment of thiolated RNA to the bound nanoparticles. The application of the compounded nano-materials for sensor development has the distinct advantage of retaining the electrical behavior …
Interfacial Friction Between Semiflexible Polymers And Crystalline Surfaces, Nikolai V. Priezjev
Interfacial Friction Between Semiflexible Polymers And Crystalline Surfaces, Nikolai V. Priezjev
Mechanical and Materials Engineering Faculty Publications
The results obtained from molecular dynamics simulations of the friction at an interface between polymer melts and weakly attractive crystalline surfaces are reported. We consider a coarse-grained bead-spring model of linear chains with adjustable intrinsic stiffness. The structure and relaxation dynamics of polymer chains near interfaces are quantified by the radius of gyration and decay of the time autocorrelation function of the first normal mode. We found that the friction coefficient at small slip velocities exhibits a distinct maximum which appears due to shear-induced alignment of semiflexible chain segments in contact with solid walls. At large slip velocities, the friction …
Evaluating Superconducting Ybco Film Properties Using Xray Photoelectron Spectroscopy, Paul N. Barnes, Justin C. Tolliver, Timothy J. Haugan, Sharmila M. Mukhopadhyay, John T. Grant
Evaluating Superconducting Ybco Film Properties Using Xray Photoelectron Spectroscopy, Paul N. Barnes, Justin C. Tolliver, Timothy J. Haugan, Sharmila M. Mukhopadhyay, John T. Grant
Mechanical and Materials Engineering Faculty Publications
Initial results have been recently reported that suggest a potential correlation exists between the full-width-halfmaximum (FWHM) of the Y(3d) peak obtained by x-ray photoelectron spectroscopy (XPS) and the critical current density a YBa2Cu3O7-x film can carry. In particular, the Y(3d5/2) demonstrated a stronger correlation. Transport currents were determined by the 4-point contact method using the 1μV/cm criterion. An apparent correlation was also suggested between the Y(3d) FWHM and ac loss data points were acquired to further test the usefulness of the correlations. Samples were created by pulsed laser deposition of YBa2 …
Dechlorination Of Environmental Contaminants Using A Hybrid Nanocatalyst: Palladium Nanoparticles Supported On Hierarchical Carbon Nanostructures, Hema Vijwani, Abinash Agrawal, Sharmila M. Mukhopadhyay
Dechlorination Of Environmental Contaminants Using A Hybrid Nanocatalyst: Palladium Nanoparticles Supported On Hierarchical Carbon Nanostructures, Hema Vijwani, Abinash Agrawal, Sharmila M. Mukhopadhyay
Mechanical and Materials Engineering Faculty Publications
This paper demonstrates the effectiveness of a new type of hybrid nanocatalyst material that combines the high surface area of nanoparticles and nanotubes with the structural robustness and ease of handling larger supports. The hybrid material is made by fabricating palladium nanoparticles on two types of carbon supports: as-received microcellular foam (Foam) and foam with carbon nanotubes anchored on the pore walls (CNT/Foam). Catalytic reductive dechlorination of carbon tetrachloride with these materials has been investigated using gas chromatography. It is seen that while both palladium-functionalized carbon supports are highly effective in the degradation of carbon tetrachloride, the rate of degradation …