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Search Publications

NIST Authors in Bold

Displaying 27176 - 27200 of 74220

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

Studying Long-term Performance of a Nano-ZnO filled Waterborne Polyurethane Coating using Spectroscopies and Microscopies

September 9, 2009
Author(s)
Xiaohong Gu, Dongmei Zhe, Stephanie S. Watson, Guodong Chen, Minhua Zhao, Paul E. Stutzman, Deborah S. Jacobs, Tinh Nguyen, Joannie W. Chin, Jonathan W. Martin
Although inorganic UV absorbers such as zinc oxide (ZnO) and cerium oxide (CeO2) exhibit numerous advantages compared to organic UV absorbers, the mechanisms of how these nanoparticles affect the long-term performance of polymeric coatings are less than

Clathrate Hydrate Physical Property Database

September 8, 2009
Author(s)
Kenneth G. Kroenlein, Chris D. Muzny, Andrei F. Kazakov, Vladimir Diky, Robert D. Chirico, E. D. Sloan, Michael D. Frenkel
To facilitate advances in application of technologies pertaining to gas hydrates, a database containing experimentally-derived information about those materials has been developed. This work is being done in association with an international effort on the

Collisional cooling of ultra-cold atom ensembles using Feshbach resonances

September 8, 2009
Author(s)
Ludwig G. Mathey, Eite Tiesinga, Paul S. Julienne, Charles W. Clark
We propose a new type of cooling mechanism for ultra-cold fermionic atom ensembles, which capitalizes on the energy dependence of inelastic collisions in the presence of a Feshbach resonance. We first discuss the case of a single magnetic resonance, and

Electrochemical Micromachining of Hastelloy B-2 with Ultrashort Voltage Pulses

September 8, 2009
Author(s)
Gordon A. Shaw, Joseph J. Maurer, Steven E. Fick, Thomas P. Moffat, J. J. Mallett, John L. Hudson
Electrochemical micromachining (ECMM) with ultrashort voltage pulses, a maskless all-electrochemical micro and nanofabrication technique, has been used to fabricate microstructures on a corrosion resistant nickel-based superalloy, Hastelloy B-2. Because of

Full-Scale Residential Smoke Alarm Performance

September 8, 2009
Author(s)
Thomas G. Cleary
A series of 24 full-scale experiments were conducted in a multi-room structure to examine the effects of alarm type (photoelectric, ionization, and dual sensor), alarm location, fabric type (100 % cotton and 100 % polyester), polyurethane foam density
Displaying 27176 - 27200 of 74220