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Search Publications

NIST Authors in Bold

Displaying 1551 - 1575 of 1856

Protein and Solvent Dynamics: How Strongly Are They Coupled?

January 1, 2004
Author(s)
G Caliskan, D Mechtani, J H. Roh, A Kisliuk, Alexei Sokolov, S Azzam, Marcus T. Cicerone, Sheng Lin-Gibson, I Peral
Analysis of Raman spectra of protein lysozyme demonstrates that its dynamics follow well the dynamics of solvents glycerol and trehalose. The protein s fast conformational fluctuations and low-frequency vibrations and their temperature variations are very

Recent Advances in Quantitative Synthetic-Polymer Mass Spectrometry at NIST

January 1, 2004
Author(s)
William E. Wallace, Charles M. Guttman
Commensurate with NIST s mission to advance the state of quantitative measurement science we have worked to develop a method to determine absolute molecular mass distribution of synthetic polymers by mass spectrometry. Work has centered on using matrix

Scattering Measurements for High Throughput Materials Science Research

January 1, 2004
Author(s)
A I. Norman, J Cabral, Alamgir Karim, Eric J. Amis
High throughput scattering methods are employed to study phase behavior over a concentration gradient of either Polystyrene (PS) in a Polystyrene/Polybutadiene (PS/PB) blend, or of diblock copoly(ethyleneoxide-butyleneoxide) in water. The combinatorial

Novel Microstructure in Polymer Blends Sheared Under Confinement

December 1, 2003
Author(s)
Jai A. Pathak, Kalman D. Migler
In this review article, we discuss the implications for the morphology of an immiscible polymer blend, or in general, an emulsion, in the limit when the two length scales, viz., the average droplet size and characteristic experimental length scale, become

Orientation of Platelets in Multilayered Nanocomposite Polymer Films

December 1, 2003
Author(s)
M M. Malwitz, Sheng Lin-Gibson, Erik K. Hobbie, Paul Butler, G Schmidt
The orientation of platelets in micron thick polymer-clay nanocomposite films was investigated by means of small-angle neutron scattering (SANS), small angle X-ray scattering (SAXS) and wide-angle X-ray diffraction (WAXD). The films with various clay

Certification of a Polystyrene Synthetic Polymer, SRM 2888

November 1, 2003
Author(s)
Charles M. Guttman, William R. Blair, B M. Fanconi, R J. Goldschmidt, William E. Wallace, S Wetzel, David L. VanderHart
The certification of a polystyrene standard reference material, SRM 2888, is described. The M w of SRM 2888 was determined by light scattering to be 7.19 x 10 +3 g/mol with a sample standard deviation of 0.14 x 10 +3 g/mol. A combined expanded uncertainty

Combinatorial Chemistry

October 13, 2003
Author(s)
J D. Hewes, Debra L. Kaiser, Alamgir Karim, Eric J. Amis
In 1995, the rapid fabrication of tens, hundreds, and, eventually, tens of thousands of samples in two-dimensional arrays of discrete microscaled samples (pixels) using lithography methods developed for the electronics industry was reported. Importantly

A Rapid Prototyping Technique for the Fabrication of Solvent-Resistant Structures

October 1, 2003
Author(s)
C Harrison, J Cabral, Christopher M. Stafford, Alamgir Karim, Eric J. Amis
We demonstrate a rapid prototyping technique for the fabrication of solvent-resistant channels up to and exceeding one millimeter in height. The fabrication of channels with such dimensions by conventional lithography would be both challenging and time

Droplet-String Deformation and Stability During Micro-Confined Shear Flow

October 1, 2003
Author(s)
Jai A. Pathak, Kalman D. Migler
We have performed experiments on model emulsions of polyisobutylene (PIB) and poly(dimethylsiloxane) (PDMS) to quantify the effect of confinement on deformation and stability of droplets and strings (threads) under flow. It is known from some of our

Structure and Magnetic Properties of Electrodeposition Co on n-GaAs (001)

September 19, 2003
Author(s)
A X. Ford, John E. Bonevich, Robert D. McMichael, Mark D. Vaudin, Thomas P. Moffat
Co thin films have been electrodeposited on n-type (001) GaAs. The structure and texture of the films were investigated using x-ray diffraction (XRD) and transmission electron microscopy (TEM) while the magnetic properties were examined using a vibrating

Reliability-Based Method for Service Life Prediction of Materials

September 17, 2003
Author(s)
Christopher C. White, Jonathan W. Martin, S F. Weber, L Shultz
Standard test methods, such as ASTM C719, evaluate sealant performance though threshold test measurements. This method and its derivatives do not offer reliable predictions of in-service performance. This presentation will detail efforts to move away from

Interdiffision in Polystyrene and End-Functional Polystyrene Thin Films Near a Solid Surface

September 10, 2003
Author(s)
Chengqing C. Wang, Vivek M. Prabhu, Christopher L. Soles, B D. Vogt, Wen-Li Wu, Eric K. Lin, Sushil K. Satija
Polymer interdiffusion near the polymer/solid interface is studied using neutron reflectometry. Bilayers of hydrogenated polystyrene (hPS) and deuterated polystyrene (dPS) or hydrogenated dicarboxy terminated polystyrene (hPS(COOH)2) and dPS are prepared

Form of Deprotection in Chemically Amplified Resists

September 1, 2003
Author(s)
Ronald L. Jones, T J. Hu, Vivek M. Prabhu, Christopher L. Soles, Eric K. Lin, Wen-Li Wu, D L. Goldfarb, M Angelopoulos
The push to mass production of patterns with sub-100 nm dimensions will require nanometer level control of feature size, including line edge roughness (LER). Control of LER and sidewall roughness within the length scale of individual molecules requires a

High-Throughput Measurements of Polymer Adhesion and Mechanical Properties

September 1, 2003
Author(s)
Christopher Stafford, Aaron M. Forster, C Harrison, Cher H. Davis, Eric J. Amis, Alamgir Karim
Polymer adhesion is important to numerous technologies including electronic packaging, coatings and paints, biomedical implants, and pressure-sensitive adhesives. The challenge is to understand the fundamental driving forces for the development of adhesive

High-Throughput Milli-Fluidic Platform for Polymer Formulations

September 1, 2003
Author(s)
Kathryn L. Beers, J Cabral, H J. Walls, Alamgir Karim, Eric J. Amis, C Harrison
Rapid prototyping of microfluidic handling devices has gained in popularity due to the ability to quickly test and modify new design features several times in one day.8-13 While elastomer-based methods have dominated the literature and are remarkably well
Displaying 1551 - 1575 of 1856