US – Page 426 – TechConnect Briefs

Coupling between Nanoscale and Microscale Modeling for MicroFluidic Devices

Jenkins J.W., Sundaram S., Makhijani V.B., CFD Research Corporation, US

Evaluation of microfluidic device and sensor designs using continuum modeling is a valuable method, but becomes more complex if nanoscale or molecular level physics must be included in the model. Recently, we have undertaken an [...]

Density Functional Calculations as a Tool for the Characterization of Ultra Thin Organic Films: Synthesis and spectroscopic characterization of RDX monolayers on glass substrates

Torres P., Cotte I., Mina N., Hernandez S.P., Chamberlain R.T., Garcia J., Lareau R., Castro M.E., The University of Puerto Rico, US

Density functional theory calculations (DFT), Raman and atomic force microscopy (AFM) were employed to study the surface chemistry of ultra thin films of RDX on glass substrates. The preparation method played a major role in [...]

Real Time Kinetic Measurements of Silver Nanocluster Growth

Mercado L., Castro M.E., Castro W., Vicuña E., Briano J.G., Ishikawa Y., Irizarry R., Solá L., Castro M.E., Castro W., University of Puerto Rico, US

Metallic clusters of noble metals are of tremendous technological importance due to their conduction properties, size, low reactivity and optical properties. Clusters containing as few as two and four silver atoms have been prepared in [...]

Growth Kinetics of Gold Nanoparticles

Murillo L.E., Viera O., Vicuña E., Briano J.G., Castro M.E., Ishikawa Y., Irizarry R., Solá L., University of Puerto Rico, US

We have measured the growth kinetics of gold nanoparticles in real time. Gold nanoparticles were formed from the reduction of gold (III) in aqueous solution and monitored with a stopped-flow reactor equipped with a diode [...]

A Systematic Search for New Scintillators using Electronic Structure Calculations

Klintenberg M., Derenzo S.E, Weber M.J., Lawrence Berkeley National Laboratory, US

A systematic study of several hundred inorganic crystal structures have been performed by means of electronic structure calculations with the goal of finding potential new scintillator materials for synthesis and testing. All X-ray or neutron [...]

Molecular Dynamics Simulation on Characteristics of Nano-sized Nickel Aluminide Dispersoids in Aluminum Matrix

Namkung M., Paik S., Wincheski R.A., NASA Langley Research Center, US

Molecular dynamics simulations were performed on the morphology of the interfaces between intermetallic nano-sized dispersoids of Ni3Al and NiAl, and a pure aluminum matrix. The lattice constants of dispersoids were initially set to be identical [...]

Phase transition induced hydrodynamic instability

Loh K-K, Saxena A., Lookman T., Parikh A., Los Alamos National Laboratory, US

Instabilities leading to oscillations in some particular properties of a system are intimately related to pattern formation. Nontrivial patterns form spontaneously as a result of the occurrence and propagation of the fronts of instability. These [...]

Enhanced Structure at the Interface Between the Polymer Matrix and Spherical Nanoparticles in Polymer Based Nanocomposites

Picu R.C., Ozmusul M.S., Rensselaer Polytechnic Institute, US

The effect of a curved solid wall on the conformations of long, flexible polymer chains is studied in a dense polymer system by means of lattice Monte Carlo simulations. The differences with respect to the [...]

Atomic-Level Description of Stress in Dense Polymeric Systems

Picu R.C., Rensselaer Polytechnic Institute, US

A new framework is being developed to describe stress production and relaxation in dnse polymeric systems. Stress is traditionally defined on the molecular scale, with the chaines being regarded as entropic springs. In this view, [...]

Simulation of Carbon Nanotube-based Nanoelectromechanical Switches

Dequesnes M., Rotkin S.V., Aluru N.R., University of Illinois at Urbana-Champaign, US

We study the pull-in voltage characteristics of several multiwall nanotube electromechanical switches such as suspended carbon nanotubes over a graphitic ground lectrode. Electromechanical analysis has been performed by accounting for three coupled energy domains: elastostatics, [...]