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Displaying 27126 - 27150 of 74178

Ultra-cold mechanical resonators coupled to atoms in an optical lattice

September 17, 2009
Author(s)
Andrew Geraci, John E. Kitching
We propose an experiment utilizing an array of cooled micro-cantilevers coupled to a sample of ultra-cold atoms trapped near a micro-fabricated surface. The cantilevers allow individual lattice site addressing for atomic state control and readout, and

A Statistical Path Loss Model for Medical Implant Communication Channels

September 16, 2009
Author(s)
Kamran Sayrafian, Wen-Bin Yang, John G. Hagedorn, Judith E. Terrill, Kamya Yazdandoost
Knowledge of the propagation media is a key step toward a successful transceiver design. Such information is typically gathered by conducting physical experiments, measuring and processing the corresponding data to obtain channel characteristics. In case

Large-Scale Integration of High-Performance Silicon Nanowire Field Effect Transistors

September 16, 2009
Author(s)
Qiliang Li, Xiaoxiao Zhu, Yang Yang, D. E. Ioannou, Hao Xiong, Doowon Kwon, John S. Suehle, Curt A. Richter
In this work we present a CMOS-compatible self-aligning process for the large-scale-integration of high performance nanowire field effect transistors with well-saturated drain currents, steep subthreshold slopes at low drain voltage and a large on / off

MORPHOLOGY AND FRACTURE OF ENAMEL

September 16, 2009
Author(s)
Sang-Won Myoung, James J. Lee, Paul Constantino, Peter Lucas, Brian R. Lawn
Teeth are remarkable biological structures, brittle but resilient. Here we examine the inter-relation between enamel morphology and crack resistance by sectioning human molar teeth after loading to fracture. The sections reveal that many cracks start from

Neutron Beta-Decay

September 16, 2009
Author(s)
Jeffrey S. Nico
Studies of low-energy processes, such as neutron beta-decay, contribute important information regarding die rent aspects of physics including nuclear and particle physics and cosmology. The information from these systems is often complementary to that

Effective three-body interactions of neutral atoms in optical lattices

September 15, 2009
Author(s)
Philip Johnson, Eite Tiesinga, James V. Porto, Carl J. Williams
We show that virtual excitations of neutral bosons to higher vibrational states in a three dimensional optical lattice generate effective, tunable, attractive three-body interactions. These effective processes can quickly decohere coherent states held in

PEG-HYDROGELS: SYNTHESIS, CHARACTERIZATION, AND CELL ENCAPSULATION

September 15, 2009
Author(s)
Sheng Lin-Gibson, Kaushik Chatterjee, James A. Cooper, William E. Wallace, Matthew Becker, Carl G. Simon Jr., Ferenc Horkay
A simple reaction to prepare controlled molecular mass (MM) poly(ethylene glycol) dimethacrylates (PEGDMs) of high purity and low polydispersity is outlined. PEGDMs were photo-polymerized to form hydrogels with and without bioactive moieties. The structure

Synthesis and Characterization of Elastin Mimetic Hybrid Polymers with Alternating Molecular Architecture and Elastomeric Properties

September 15, 2009
Author(s)
Sheng Lin-Gibson, Sarah E. Grieshaber, Alexandra J. Farran, Kristi L. Kiick, Xinqiao Jia
We are interested in developing elastin mimetic hybrid polymers (EMHPs) that capture the multiblock molecular architecture of tropoelastin as well as the remarkable elasticity of mature elastin. In this study, multiblock EMHPs containing flexible synthetic

ThermoData Engine (TDE) Version 2E-2009

September 15, 2009
Author(s)
Preston Craig, Robert D. Chirico, Vladimir Diky, Ilmutdin Abdulagatov, Thomas J. Bruno, Michael D. Frenkel
ThermoData Engine (TDE) Version 2E-2009 is a software expert system for critical evaluation of thermophysical properties of selected explosive materials through implementation of dynamic data evaluation. There are 62 compounds in version 2E-2009. The

Ultracold Atom Spin Field Effect Transistor

September 14, 2009
Author(s)
Jay Vaishnav, Julius Ruseckas, Charles W. Clark, Gediminas Juzelunas
We propose a method of constructing cold atom analogs of the spintronic device known as the Datta-Das transistor (DDT), which despite its seminal conceptual role in spintronics, has never been successfully realized with electrons. We propose two

An electrical pulse-heated Kosky bar technique for high strain rate flow stress measurements of rapidly heated metals

September 13, 2009
Author(s)
Steven P. Mates, Stephen W. Banovic, Richard L. Rhorer, Timothy J. Burns, Eric P. Whitenton, D Basak
We have developed a unique electrical pulse-heated Kolsky Bar technique for measuring the flow stress of metals at heating rates of up to 6000 °C per second and strain rates up to 10^4 per second. Under these conditions, which are approaching those found

Microbial colonization on polymers: Effects of sample preparation and incorporation of quaternary ammonium salts

September 13, 2009
Author(s)
Nancy J. Lin, Diana N. Zeiger, Joseph M. Antonucci, Bruce O. Fowler, Christopher M. Stafford, Sheng Lin-Gibson
Controlling bacterial growth in the oral environment presents many challenges. To address these challenges, new materials and treatments are needed along with controlled, reproducible methods to evaluate their efficacy. In this study, a reproducible method

A Spectroscopic Polarimeter For Detecting Chiral Signatures In Astrobiological Samples

September 11, 2009
Author(s)
Baoliang Wang, William Sparks, Thomas Germer, Andy Leadbetter
We have developed a polarimeter for accurately measuring both the circular and linear polarization components of a light beam from 400 nm to 800 nm. This polarimeter is designed to work at low light levels that are typical in astronomical applications. It

Contact and Stress Anisotropies in Start Up Flows of Collodial Suspensions

September 11, 2009
Author(s)
Nicos Martys, William L. George, Didier Lootens, Pascal Hebraud
Spatio-temporal correlations in start-up flows of attractive colloids are explored by numerical simulations. The suspension is first allowed to flocculate during a time tw, then the stress necessary to induce its flow is computed. Whereas at low volume
Displaying 27126 - 27150 of 74178