Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 5 of 5
Full-Text Articles in Engineering
Design And Demonstration Of A Small-Animal Up-Conversion Imager, Christopher Salthouse, Scott Hildebrand, Ralph Weissleder, Umar Mahmood
Design And Demonstration Of A Small-Animal Up-Conversion Imager, Christopher Salthouse, Scott Hildebrand, Ralph Weissleder, Umar Mahmood
Christopher Salthouse
This first small-animal up-conversion imager (SAUCI) was developed and used for in-vivo imaging of up-converting nanoparticles (UCNs.) Unlike traditional fluorophores, UCNs absorb multiple lower-energy photons and emit a single higher-energy photon. This unique physical process makes it possible to image deeper into tissue with lower background signals. In vivo imaging of particle accumulation in the liver was demonstrated following intravenous injection of particles.
Superhydrophobicity And Contact-Line Issues, Lc Gao, Ay Fadeev, Tj Mccarthy
Superhydrophobicity And Contact-Line Issues, Lc Gao, Ay Fadeev, Tj Mccarthy
Lixin Gao
The wettability of several superhydrophobic surfaces that were prepared recently by simple, mostly single-step methods is described and compared with the wettability of surfaces that are less hydrophobic. We explain why two length scales of topography can be important for controlling the hydrophobicity of some surfaces (the lotus effect). Contact-angle hysteresis (difference between the advancing, θA, and receding, θR, contact angles) is discussed and explained, particularly with regard to its contribution to water repellency. Perfect hydrophobicity (θA/θR = 180°/180°) and a method for distinguishing perfectly hydrophobic surfaces from those that are almost perfectly hydrophobic are described and discussed. The Wenzel …
Power-Efficient Topology Control For Static Wireless Networks With Switched Beam Directional Antennas, V Namboodiri, Lx Gao, R Janaswamy
Power-Efficient Topology Control For Static Wireless Networks With Switched Beam Directional Antennas, V Namboodiri, Lx Gao, R Janaswamy
Lixin Gao
Topology control problems are associated with assignment of power levels to nodes of a wireless network so that the resulting graph topology satisfies certain properties. In this paper we consider the problem of power-efficient topology control with switched beam directional antennas taking into account their non-uniform radiation pattern within the beamwidth. Previous work in the area have all assumed a uniform gain model with these antennas which renders antenna orientation insignificant as a parameter in topology control algorithms. We present algorithms that take into account a model of non-uniform gain with the objectives of minimizing the total power and maximum …
High Resolution Observations Of Insects In The Atmospheric Boundary Layer, Stephen Frasier, R. F. Contreras
High Resolution Observations Of Insects In The Atmospheric Boundary Layer, Stephen Frasier, R. F. Contreras
Stephen Frasier
High spatial and temporal resolution S-band radar observations of insects in the atmospheric boundary layer (ABL) are described. The observations were acquired with a frequency-modulated continuous-wave (FMCW) radar during the 2002 International H20 Project (IHOP_2002) held in Oklahoma in the months of May and June 2002. During the observational period the boundary layer was convective with a few periods of rain. Rayleigh scattering from particulate scatterers (i.e., insects) dominates the return; however, Bragg scattering from refractive index turbulence is also significant, especially at the top of the afternoon boundary layer. There is a strong diurnal signal in the insect backscatter: …
Terahertz Detection In Single Wall Carbon Nanotubes, Eric Polizzi, K. S. Yngvesson, J. Nicholson, S. H. Adams, C. Chan, K. Fu, R Zannoni
Terahertz Detection In Single Wall Carbon Nanotubes, Eric Polizzi, K. S. Yngvesson, J. Nicholson, S. H. Adams, C. Chan, K. Fu, R Zannoni
Eric Polizzi
It is reported that terahertz radiation from 0.69 to 2.54 THz has been sensitively detected in a device consisting of bundles of carbon nanotubes containing single wall metallic carbon nanotubes, quasioptically coupled through a lithographically fabricated antenna, and a silicon lens. The measured data are consistent with a bolometric detection process in the metallic tubes and the devices show promise for operation well above 4.2 K.