U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Publications by: Jack F. Douglas (Fed)

Search Title, Abstract, Conference, Citation, Keyword or Author
Displaying 326 - 350 of 355

Structured Polymeric Templates: Combinatorial Probes for Cellular Response

January 1, 2001
Author(s)
A Sehgal, Jack F. Douglas, Francis W. Wang, Carl G. Simon Jr., Alamgir Karim, Eric J. Amis
Novel high-throughput gradient methods have been developed to generate a range of surface structures by dewetting and phase separation on chemically patterned substrates. The research is motivated by an increasing awareness in the biomedical industry and

Modification of the Phase Stability of Polymer Blends by Fillers

November 1, 2000
Author(s)
Alamgir Karim, D W. Liu, Jack F. Douglas, A Nakatani, Eric J. Amis
We investigate the influence of surface modified filler particles on the phase stability of a model blend of polystyrene (PS) and polybutadiene (PB). The upper critical solution cloud point curve of PS/PB is destabilized (upward shift of critical

Preparation and Characterization of Polymer/Dendrimer Blends: Final Report, March 2000

March 1, 2000
Author(s)
Eric J. Amis, Barry J. Bauer, A Topp, F Groehn, T J. Prosa, B D. Viers, Da-Wei Liu, K A. Barnes, C L. Jackson, G Nisato, Alamgir Karim, Jack F. Douglas
This report is a summary of the results of measurement and characterization on dendritically branched polymers that was done under Army Research Office Grant contract 35109-CH. This summary encompasses 3 previous NISTIR's for consecutive 12 month periods

Polymer-Surface Interactions in Nanofilled Polymers

January 1, 2000
Author(s)
Alamgir Karim, Jack F. Douglas
An understanding of the influence of polymer-surface interactions on the interfacial properties of nanoparticle fillers in polymer matrices is critical for applications of nanoparticle filled polymer materials. The infuence of nanoparticle-surace

Filler-Induced Composition Waves in Phase-Separating Polymer Blends

November 1, 1999
Author(s)
B P. Lee, Jack F. Douglas, S C. Glotzer
The influence of a dilute concentration of filler particles on polymer blend phase separation is investigated computationally using a generalization of the Cahn-Hilliard-Cook (CHC) theory to include model filler particles (spheres, fibers, platelets)

Lattice Model of Living Polymerization I. Basic Thermodynamic Properties

October 1, 1999
Author(s)
J Dudowicz, Karl Freed, Jack F. Douglas
A Flory-Huggins type model of living polymerization is formulated, incorporating chain stiffness, variable initiator concentration and polymer-polymer interactions. Basic equilibrium properties [average chain length L, average fraction of associated

Transient Target Patterns in Phase Separating Filled Polymer Blends

September 1, 1999
Author(s)
Alamgir Karim, Jack F. Douglas, G Nisato, D W. Liu, Eric J. Amis
Recent simulations have indicated that the presence of filler particles in a phase separating blend can induce the development of composition waves having the symmetry of the filler particles. We investigate these predictions through atomic force

Thermal and Mass Diffusion in a Semidilute Good Solvent-Polymer Solution

August 1, 1999
Author(s)
K J. Zhang, M E. Briggs, R W. Gammon, J V. Sengers, Jack F. Douglas
The Soret coefficient S T and collective (mass) diffusion coefficient D c of polystyrene dissolved in the good solvent toluene is measured over a range of concentrations and molecular weights using an optical beam deflection method. Our measurements

Mean-Field-Scaling in Lattice Boltzmann Fluid Mixtures

June 1, 1999
Author(s)
Nicos Martys, Jack F. Douglas
Basic equilibrium properties of Lattice Boltzmann (LB) fluid mixtures (coexistence curve, surface tension, and interfacial profile) are calculated to characterize the critical phenomena occurring in these model liquids and to establish a reduced variable

Integral Equation Approach to Condensed Matter Relaxation

January 1, 1999
Author(s)
Jack F. Douglas
A model of relaxation in supercooled and polymer liquids is developed starting from an integral equation describing relaxation in liquids near thermal equilibrium and probabilistic modeling of the dynamic heterogeneity presumed to occur in these complex