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Displaying 28901 - 28925 of 74219

Diffuse Reflectance of Sintered and Pressed Polytetrafluroethylene (PTFE)

October 16, 2008
Author(s)
P Y. Barnes, E A. Early
Polytetrafluoroethylene (PTFE) is widely used in applications requiring a material with a diffuse reflectance factor close to unity. The bidirectional reflenctance distribution function (BRDF) of both pressed and sintered samples was measured as a function

Diffusional Creep: Stresses and Strain Rates in Thin films and Multilayers

October 16, 2008
Author(s)
Daniel Josell, Timothy P. Weihs, H Gao
In this article, we discuss creep deformation as it relates to thin films and multilayer foils. We begin by reviewing experimental techniques for studying creep deformation in thin-film geometries, listing the pros and cons of each; then we discuss the use

Digital Rights, Risk and Assurance

October 16, 2008
Author(s)
Gordon E. Lyon
A trust and assurance perspective applies readily to the distribution of digital products over the Internet: It identifies when digital rights remain viable, even with eventual mishaps and leaks that attend every long-term operation. An assurance system

Directional Solidification in a AgCuSn Eutectic Alloy

October 16, 2008
Author(s)
Robert J. Schaefer, D J. Lewis
An experimental study of microstructures in a directionally solidified, near-eutectic solder Ag-Cu-Sn alloy has been completed. This material is an important candidate for use as a lead-free solder, and the studies show the origin and velocity dependence

Discrete Variable Representations for Singular Hamiltonians

October 16, 2008
Author(s)
B I. Schneider, N Nygaard
We discuss the application of the Discrete Variable Representation to Schr dinger problems which involve singular Hamiltonians. Unlike recent authors which invoke transformations to rid the eigenvalue equation of singularities at the cost of added

Dispersion and Shear Viscosity of a Simulated Polymer Nanocomposite

October 16, 2008
Author(s)
Francis W. Starr, Jack F. Douglas, S C. Glotzer
Using molecular dynamics simulations, we explore properties affecting nano-filler dispersion in a dense bead-spring polymer melt, and how the state of dispersion alters the response of the system to shear. We determine a simple metric to determine the

Dissolution Dynamics of Artificially Structured Materials

October 16, 2008
Author(s)
M Shima, L Salamanca-Riba, Thomas P. Moffat
The anodic dissolution of an ultrathin cobalt film buried beneath a copper overlayer has been studied using voltammetry and chronoamperometry. The films were produced by sequential electrodeposition of cobalt and copper layers from a solution of 1.5 mol/L

Distant Entanglement with Nearest Neighbor Interactions

October 16, 2008
Author(s)
G K. Brennen
Preparing many body entangled states efficiently using available interactions is a challenging task. One solution may be to couple a system collectively with a probe that leaves residual entanglement in the system. We investigate the entanglement produced

Domain Structures in Low Ionic Strength Polyelectrolyte Solutions

October 16, 2008
Author(s)
B D. Ermi, Eric J. Amis
A steep upturn at low angles dominates the small angle neutron scattering profile of low ionic strength polyelectrolyte solutions when measurements are extended to low angles not typical of most studies. This behavior is consistent with static and dynamic

Dosimetry of Beta-Ray Opthalmic Applicators: Comparison of Different Measurement Methods

October 16, 2008
Author(s)
Christopher G. Soares, S Vynckier, H Jarvinen, W G. Cross, J Hokkanen, P Sipila, D Fluhs, B Schaeken, F A. Mourtada, G A. Bass, T T. Williams
An international intercomparison of the dosimetry of three beta particle emitting ophthalmic applicators was performed, which involved measurements with radiochromic film, thermoluminescence dosimeters (TLDs), alanine pellets, plastic scintillators, an

Draft Radioanalytical Water and Soil Performance Testing Uncertainty Acceptance Criteria Derived From Historical Mixed-Analyte Performance Evaluation Program Results

October 16, 2008
Author(s)
Kenneth G. Inn, James J. Filliben, James Dahlgran
Radioanalytical performance testing programs provide radioassay laboratories, regulators and the public performance-based evidence that measurement capabilities are in control. Performance acceptance criteria that combine aspects of measurements difference

Dynamic Hardness of Porous and Nonporous Materials Using a Dropped Ball

October 16, 2008
Author(s)
R B. Clough
A method for measuring the dynamic hardness of materials using a dropped ball is developed and applied to nonporous cold-rolled plain carbon (1018) steel. A new feature of the method is that it corrects the hardness measurement for the effects of pile-ups

Dynamical Heterogeneities in the Ising Spin Glass

October 16, 2008
Author(s)
S C. Glotzer, N Jan, T Lookman, A B. MacIsaac, P H. Poole
We investigate the relationship between bulk and local relaxation in the Ising spin glass (in 2 and 3 dimensions) for temperatures above but approaching the glass transition temperature, using Monte Carlo computer simulations. We find that the stretched

Dynamical Heterogeneity in the Ising Spin Glass

October 16, 2008
Author(s)
S C. Glotzer, N Jan, T Lookman, A B. MacIsaac, P H. Poole
We investigate the relationship between bulk and local relaxation in the Ising spin glass (in 2 and 3 dimensions) for temperatures above but approaching the glass transition temperature, using Monte Carlo computer simulations. We find that the stretched

Dynamics of DNA Through a Nanopore

October 16, 2008
Author(s)
Robert Hagwood
Single stranded DNA is modeled as a flexible polymer. The motion of such DNA in a vessel partitioned by a membrane containing a cylindrical nanopore is modeled. Statistical quantities such as the probability that a polymer end is at the pore entrance at

eBook Standards

October 16, 2008
Author(s)
J Potman
A discussion of current and proposed eBook standards and their applications. The discussions include: Open eBook Publication Structure (OEBPS), Portable Document Format (PDF), Open eBook File Format (OEBFF), Electronic Book Exchange System (EBX)

Edge Toughness and Material Properties of Dental Ceramics

October 16, 2008
Author(s)
Janet Quinn, Isabel K. Lloyd
Objectives: In the edge chipping test, an increasing load is applied near the edge of a material until a chip is formed. Higher loads are required to form chips at greater distances from the specimen edge. The chip loads are plotted against the edge

Edge-Chip Testing of Glass at Different Applied Force Angles

October 16, 2008
Author(s)
Janet Quinn, R Mohan V. C.
Current edge-chip material testing procedures involve applying an increasing perpendicular force near a specimen edge until a chip forms. In this report, the effects of applied forces that are not perpendicular are studied, including quantitative changes
Displaying 28901 - 28925 of 74219