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Search Publications

NIST Authors in Bold

Displaying 3476 - 3500 of 74040

Modal Reconstruction of Aspheric Surfaces From Experimental Second Derivatives

October 12, 2021
Author(s)
Nadia Machkour-Deshayes, Byoung C. Kim, Robert S. Polvani, Ulf Griesmann
A method for the measurement of precise aspheric optical surfaces based on measurements of the second derivatives of the surface is evaluated. A compact phase-measuring interferometer is used to determine the second derivatives of a surface on a survey

Model for Dispersion Rheology

October 12, 2021
Author(s)
J Bicerano, Jack F. Douglas, D A. Brune
A general model of the viscosity of complex-shaped particle dispersions is developed based on an exact virial expansion about the low concentration limit and a mathematical analogy between the hydrodynamics of concentrated particle suspensions and the

Molecular Computers for Solving Computational Decision Problems

October 12, 2021
Author(s)
Z Amitay, R Kosloff, S R. Leone
State-selective coherent control tailored molecular wave packets is implemented for solving computational decision problems. The current study involves graphs composed of vertices and edges, and the computational task is to determine the connectivity of a

Molecular Modeling of the Thermal Decomposition of Polymers

October 12, 2021
Author(s)
S I. Stoliarov, H Zhang, P R. Westmoreland, R Lyon, Marc R. Nyden
Applications presented in this work demonstrate the potential for using quantum mechanics and molecular simulations to determine the mechanisms and rates of the thermal decomposition of polymers. The expectation is that these capabilities can be used to

Molecular Production in Two Component Atomic Fermi Gases

October 12, 2021
Author(s)
J Chwedenczuk, K Goral, T K hler, Paul S. Julienne
We provide a practical approach to the molecular production via linear downward sweeps of Feshbach resonances in degenerate Fermi gases containing incoherent mixtures of two atomic spin states. We show that the efficiency of the association of atoms is

Molecular-scale Structural and Functional Characterization of Sparsely Tethered Bilayer Membranes

October 12, 2021
Author(s)
Duncan McGillivray, Gintaras Valincius, David J. Vanderah, W Febo-Ayala, John T. Woodward IV, F Hienrich, John J. Kasianowicz, M Losche
Surface-tethered biomimetic bilayer membranes (tethered lipid bilayer membranes, tBLMs) have been formed on gold surfaces from phospholipids and a synthetic 1-thiahexa(ethy lene oxide) lipid, WC14. They have been characterized using electrochemical

Morphology Dependence of Ultrafast Emission From Metal-Dendrimer Nanocomposites

October 12, 2021
Author(s)
O Varnavski, T Goodson, F Groehn, Barry J. Bauer, Eric J. Amis
We report the results of ultra-fast fluorescence investigations from gold-dendrimer nanocomposites of different morphologies. Femtosecond depolarized emission has been detected and characterized for Polyamidoamine (PAMAM) G5-based gold colloids, which

Multi-Pole Representation of the Dielectric Matrix

October 12, 2021
Author(s)
J A. Soininen, J J. Rehr, Eric L. Shirley
A good approximation for the electron self-energy or the electron quasiparticle properties is needed for an accurate calculation of x-ray absorption spectra. The GW approximation (GWA) has been found to be relatively reliable in predicting the

Nano/Bioscience and Technology Education for the 21st Century

October 12, 2021
Author(s)
J Jacobs, Winnie Wong-Ng, Gale A. Holmes, Richard F. Kayser
NEW:Update 2005, the 20th annual workshops for science and technology educators with the theme, NANO/BIOSCIENCE AND TECHNOLOGY EDUCATION FOR THE 21ST CENTURY, was hosted by the National Institute of Standards and Technology/Materials Science and

Near-Field Intensity Correlations in Semicontinuous Metal-Dielectric Films

October 12, 2021
Author(s)
K Seal, A K. Sarychev, H Noh, D A. Genov, A Yamilov, Vladimir Shalaev, Z C. Ying, H Cao
Spatial intensity correlation functions are obtained from near-field scanning optical microscope measurements of semicontinuous metal-dielectric films. The concentration of metal particles on a dielectric surface is varied over a wide range to control the

Near-Field Second Harmonic Microscopy of Thin Ferroelectric Films

October 12, 2021
Author(s)
V Smolyaninova, H Y. Liang, C H. Lee, C C. Davis, L D. Rotter, Debra Kaiser
Near-field second harmonic microscopy is ideally suited for studies of local nonlinearity and poling of ferroelectric materials at the microscopic level. Its main advantages in comparison with other scanning probe techniques are the possibility of fast

Near-Field, Spherical-Scanning Antenna Measurements With Nonideal Probe Locations

October 12, 2021
Author(s)
Ronald C. Wittmann, Bradley Alpert, Michael H. Francis
We introduce a near-field, spherical-scanning algorithm for antenna measurements that relaxes the usual condition requiring data points to be on a regular spherical grid. Computational complexity is of the same order as for the standard (ideal-positioning)

NEMI Group Recommends 'Standardized' Lead-Free Solder Alternative

October 12, 2021
Author(s)
J Bath, C A. Handwerker, E Bradley
Increasing global concern about the environment is bringing regulatory and consumer pressure on the electronics industry in Europe and Japan to reduce or completely eliminate the use of lead in products. As Europe and Japan move toward lead-free

NEMI Tin Whisker Test Method Standards

October 12, 2021
Author(s)
I Boguslavsky, P Bush, E Kam-Lum, M Kwoka, J McCullen, K Spalding, K Vo, Maureen E. Williams
The need to better understand whisker growth has dramatically increased as component suppliers convert from tin-lead (SnPb) finishes to Pb-free finishes of Sn and low -alloy-content Sn-based finishes. Whiskers are spontaneous growth of metal filaments

NEXAFS Characterization of Poly(amino acids)

October 12, 2021
Author(s)
N T. Samuel, Daniel A. Fischer, David G. Castner
The near-edge x-ray absorption fine structure (NEXAFS) spectra of poly(amino acids) at the carbon, nitrogen and oxygen k-edges are investigated in this study. The poly(amino acid) NEXAFS spectra at the k-edges closely resemble the spectra of the

NiO: A Charge Transfer or Mott-Hubbard Insulator

October 12, 2021
Author(s)
T M. Schuler, D L. Ederer, S Itza-Ortiz, G T. Woods, T A. Callcott, Joseph Woicik
Using site-specific soft x-ray emission and absoroption spectroscopy in conjunction with site-specific x-ray photoelectron spectroscopy, we measure the magnitude of the insulating band gap of NiO to be approximately 2.0 eV, comparable to that predicted by

Non-Contact Tuning Fork Position Sensing for Hollow-Pyramid Near-Field Cantilevered Probes

October 12, 2021
Author(s)
A Ambrosio, E Cafali, S Spadaro, S Patane, Maria Allegrini, D Albert, E Oesterschulze
We demonstrate that tuning fork sensing provides a stable non-contact mode operation when applied to near-field optical microscopy employing cantilevered probes. Detrimental damping effects that have so far limited the practical use of these otherwise very
Displaying 3476 - 3500 of 74040