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Search Publications

NIST Authors in Bold

Displaying 20376 - 20400 of 73960

Nanoscale mechanics by tomographic contact resonance atomic force microscopy

January 23, 2014
Author(s)
Gheorghe NMN Stan, Santiago Solares, Bede Pittenger, Natalia Erina, Chanmin Su
We report on a quantifiable depth-dependent contact resonance AFM (CR-AFM) measurements over polystyrene-polypropylene (PS-PP) polymer blends to detail surface and sub-surface features in terms of elastic modulus and mechanical dissipation. The depth

Optimally Focused Cold Atom Systems Obtained Using Density-Density Correlations

January 23, 2014
Author(s)
Ian B. Spielman, Andika Putra, Daniel Campbell, Ryan Price, Subhadeep De
Resonant absorption imaging is a common technique for detecting the two-dimensional column density of ultracold atom systems. In many cases, the system’s thickness along the imaging direction greatly exceeds the imaging system’s depth of field, making the

Review of Past Performance and Further Development of Modeling Techniques for Collapse Assessment of Existing Reinforced Concrete Buildings

January 23, 2014
Author(s)
Kenneth Elwood, Jack Baker, Craig Comartin, William Holmes, Jack Moehle, Peter Somers
The first phase of work of the Program Plan, documented in this report, included the identification of critical deficiencies, refinement of the list of common deficiencies, and development of collapse mitigation strategies for older reinforced concrete

Adaptive Composite B-Spline Grid Generation for Interactive 3D Visualizations

January 22, 2014
Author(s)
Bonita V. Saunders, Qiming Wang, Brian Antonishek
We describe an adaptive grid generation technique based on the composition of tensor product B-spline mappings, T and Phi, where Phi maps the unit square onto itself and T maps the unit square onto the desired physical domain. Variational methods are used

NIST 1-kilonewton sine force calibration system

January 22, 2014
Author(s)
Akobuije D. Chijioke, Ricky L. Seifarth, Zeina J. Kubarych
Many force-measurement applications are of a dynamic nature, and in recent decades there has been much progress in demonstrating and developing dynamic calibration systems for force transducers. The National Institute of Standards and Technology (NIST), U

Ghost Modes and Continuum Scattering in the Dimerized Distorted Kagome Lattice Antiferromagnet Rb 2 Cu 3 SnF 12

January 21, 2014
Author(s)
K. Matan, Y. Nambu, Yang Zhao, T.J. Sato, Y. Fukumoto, T. Ono, H. Tanaka, Collin L. Broholm, A. Podlesnyak, G. Ehlers
Magnetic excitations of the pinwheel valence bond solid state in the distorted kagome lattice antiferromagnet Rb 2Cu 3SnF 12 were studied using high-resolution inelastic neutron scattering. A weakly dispersive mode around 5 meV and duplicate triplet

Isolation of Specific Small Diameter Single-Wall Carbon Nanotube Species via Aqueous Two-Phase Extraction

January 21, 2014
Author(s)
Jeffrey A. Fagan, Constantine Y. Khripin, Carlos A. Silvera Batista, Jeffrey R. Simpson, Angela R. Hight Walker, Ming Zheng
Aqueous two-phase extraction (ATPE) is demonstrated to enable isolation of multiple semiconducting and metallic single-wall carbon nanotube species from a small diameter synthetic mixture. Separation by ATPE is rapid and robust, with remarkable tunability

Saponins: A sustainable surfactant. From its microwave-assisted extraction to the synthesis of monodisperse latices

January 21, 2014
Author(s)
Charlene Schnitt, Bruno Grassl, Julien C. Gigault, Vincent A. Hackley, Gaetane Lespes, Jacques Desbrieres, Virginie Pellerin, Stephanie Reynaud
Synthetic surfactants are widely used in emulsion polymerization, but it is increasingly desirable to replace them with naturally derived molecules with a reduced environmental burden. This study demonstrates the use of saponins as sustainable and

Measurement Techniques for RF Nanoelectronics

January 20, 2014
Author(s)
Thomas M. Wallis, Luca Pierantoni
In 1882, in a lecture at the University of Leiden, Nobel prize-winner Heike Kammerlingh Onnes coined the motto: “Through Measurement to Knowledge” [1]. In that same lecture, he gave many historical examples of how measurements have fostered insight

Quantification of total serum transferrin and transferrin sialoforms in human serum; an alternative method for the determination of carbohydrate-deficient transferrin in clinical samples

January 20, 2014
Author(s)
Yoana Y. Nuevo Ordonez, William C. Davis, Raymond F. Anton
Carbohydrate deficient transferrin (CDT) measurements in human serum constitute the most specific marker for chronic heavy alcohol use and congenital disorders of glycosylation in proteins. Therefore, the development of precise and accurate analytical

SPRITE: A modernized approach to scanning probe contact resonance imaging

January 20, 2014
Author(s)
Anthony B. Kos, Jason P. Killgore, Donna C. Hurley
We describe a system for contact resonance tracking called Scanning Probe Resonance Image Tracking Electronics (SPRITE). SPRITE can image two contact resonance frequencies simultaneously and thus can be used to acquire quantitative mechanical properties

Possibilities and Tradeoffs for Low-GWP Refrigerants

January 19, 2014
Author(s)
Mark O. McLinden
presentation at ASHRAE Winter Conference: We explore the possibilities for refrigerants having low global warming potential (GWP) through two distinct, but complementary, approaches. In an “exploration of thermodynamic space” we define the limits of what

Thermodynamic Performance Limits of the Vapor Compression Cycle

January 19, 2014
Author(s)
Piotr A. Domanski, J S. Brown, Jae H. Heo, Mark O. McLinden
This presentation discusses the thermodynamic performance limits of the vapor compression cycle. We have applied evolutionary algorithms to explore the performance of hypothetical refrigerants defined by the thermodynamic parameters used by the extended

Thermodynamic properties of 1-phenylnaphthalene and 2-phenylnaphthalene

January 18, 2014
Author(s)
Robert D. Chirico, Andrei F. Kazakov, William V. Steele
Measurements leading to the calculation of thermodynamic properties in the ideal-gas state for 1- phenylnaphthalene (Chemical Abstracts registry number [605-02-7]) and 2-phenylnaphthalene (Chemical Abstracts registry number [612-94-2]) are reported

Study of CeI 3 evaporation in the presence of Group 13 metal-iodides

January 17, 2014
Author(s)
John J. Curry, Albert Henins, E. G. Estupinan, S. D. Shastri, Jonathan E. Hardis, W. P. Lapatovich
The influence of GaI$_3$, InI, and TlI on the evaporation characteristics of CeI$_3$ have been studied over the temperature range 900 K to 1400 K using x-ray induced fluorescence. The total vapor densities, summed over all atomic and molecular species, of

ACOUSTIC GAS THERMOMETRY

January 16, 2014
Author(s)
Michael R. Moldover, Roberto M. Gavioso, James B. Mehl, Laurent Pitre, Michael de Podesta, Jintao Zhang
We review the principles, techniques and results from primary acoustic gas thermometry (AGT). Since the establishment of ITS-90, the International Temperature Scale of 1990, spherical and quasi-spherical cavity resonators have been used to realize primary

Acoustic Gas Thermometry

January 16, 2014
Author(s)
Michael R. Moldover, Roberto M. Gavioso, James B. Mehl, Laurent Pitre, Michael de Podesta, Jintao Zhang
Primary acoustic gas thermometry (AGT) exploits the simple relationship between the speed of sound in a dilute gas u and the thermodynamic temperature T of the gas. For monatomic gases such as argon and helium, u2 = (5/3) kT/m, in the limit of zero

Guide to Attribute Based Access Control (ABAC) Definition and Considerations

January 16, 2014
Author(s)
Chung Tong Hu, David F. Ferraiolo, David R. Kuhn, Adam Schnitzer, Kenneth Sandlin, Robert Miller, Karen Scarfone
This document provides Federal agencies with a definition of attribute based access control (ABAC). ABAC is a logical access control methodology where authorization to perform a set of operations is determined by evaluating attributes associated with the

Quantitative Testing of Fire Scenario Hypotheses: A Bayesian Inference Approach

January 16, 2014
Author(s)
Kristopher J. Overholt, Ofodike A. Ezekoye
Fire models are routinely used to evaluate life safety aspects of building design projects and are being used more often in fire and arson investigations as well as reconstructions of firefighter line-of-duty deaths and injuries. A fire within a

Template synthesis of gold nanoparticles with an organic molecular cage

January 16, 2014
Author(s)
Ryan McCaffrey, Hai Long, Yinghua Jin, Aric Sanders, Wounjhang Park, Wei Zhang
We report a novel strategy for the controlled synthesis of gold nanoparticles (AuNPs) with narrow size distribution (1.9 plus or minus} 0.4 nm) through NP nucleation and growth inside the cavity of a well-defined three-dimensional, shape-persistent organic
Displaying 20376 - 20400 of 73960
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