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Displaying 19151 - 19175 of 74189

International Comparisons of Network Time Protocol Servers

December 4, 2014
Author(s)
Michael A. Lombardi, Judah Levine, Jose M. Lopez, Francisco Jimenez, John Bernard, Marina Gertsvolf, Harold Sanchez, Oscar G. Fallas, Liz C. Hernandez Ferero, Ricardo de Carvalho, Mario Fittipaldi, Raul Solis, Franklin Espejo
This paper describes a recently designed system that measures the time transmitted by network time protocol (NTP) servers located in North, Central, and South America. Direct measurements of the time transmitted by each server are obtained by comparing the

Measured Ionosphere Delay Correction for Code-Based GPS Time Transfer

December 4, 2014
Author(s)
Victor S. Zhang, Zhiqi Li
Nowadays, more and more dual-frequency, multichannel receivers are used in GPS time and frequency transfer applications. Instead of using the modeled ionosphere delay correction or using the IGS ionospheric map, we can obtain the ionosphere delay

Periodic dynamics, localization metastability, and elastic interaction of colloidal particles with confining surfaces and helicoidal structure of cholesteric liquid crystals

December 4, 2014
Author(s)
Michael C. Varney, Qiaoxuan Zhang, Mykola Tasinkevych, Nuno M. Silvestre, Kristine A. Bertness, Ivan I. Smalyukh
Although nematic and cholesteric liquid crystals are three-dimensional fluids, they also possess long- range orientational ordering of their constituent molecules, supporting both topological defects and chiral superstructures. Implications of this

The Use of Cause-and-Effect Analysis to Design a High Quality Nano-Cyto-Toxicology Assay

December 4, 2014
Author(s)
Matthias Rosslein, John T. Elliott, Marc L. Salit, Elijah Petersen, Cordula Hirsch, Harald Krug, Peter Wick
An important consideration in developing standards and regulations that govern the production and use of commercial nanoscale materials is the development of robust and reliable measurements to assess potential biological effects of these nanomaterials

Kinetic Polymer Arrest in Percolated SWNT Networks

December 3, 2014
Author(s)
Rana NMN Ashkar, Mansour Abdul Baki, Madhu Sudan Tyagi, Antonio Faraone, Paul Butler, Ramanan Krishnamoorti
The inclusion of single-wall carbon nanotubes (SWNT) in a polymer, with interchain distances comparable to the SWNT diameter, can significantly perturb the structural and dynamical properties of interfacial polymeric units. For SWNT concentrations above

Polaron-Mediated Spin Correlations in Metallic and Insulating La 1-x A x MnO 3 (A=Ca,Sr, or Ba)

December 3, 2014
Author(s)
Joel Helton, Daniel M Pajerowski, Yiming Qiu, Yang Zhao, Dmitry A. Shulyatev, Yakov M. Mukovskii, Georgii L. Bychkov, Sergei N. Barilo, Jeffrey W. Lynn
Neutron spectroscopy measurements reveal short-range spin correlations near and above the ferromagnetic-paramagnetic phase transition in manganite materials of the form La 10zA xMnO 3, including samples with an insulating ground state as well as colossal

Quantum Critical Fluctuations in the Heavy Fermion compound Ce(Ni^s0.935^Pd 0.065 ) 2 Ge 2

December 3, 2014
Author(s)
C. H. Wang, L. Poudel, A. E. Taylor, J .M. Lawrence, A. D. Christianson, Sung Chang, Jose Rodriguez Rivera, Jeffrey W. Lynn, A. A. Podlesnyak, G. Ehlers, R. E. Baumbach, E. D. Bauer, K. Gofryk, F. Ronning, K. J. McClellan, J. D. Thompson
Inelastic neutron scattering experiments were performed on a single crystal of the heavy Fermion compound Ce(Ni 0.935Pd 0.065) 2Ge 2 in order to study the spin fluctuations near an antiferromagnetic (AF) quantum critical point (QCP). We find that the

Assessment of Crude Oil and a Dispersant in a Simulated Spartina alterniflora Salt Marsh Ecosystem

December 1, 2014
Author(s)
P Key, K Chung, C Cooksey, DeLorenzo M, M Fulton, D Greenfield, T Greig, J Hylund, Bryant C. Nelson, Varun Patel, P Pennington, Elijah Petersen, E Wirth
NOAA's Environmental Sensitivity Index (ESI) lists saltmarshes along the Atlantic and Gulf Coasts as the most vulnerable habitat to oil spills. As a result of the Deepwater Horizon offshore drilling rig accident, more that 200 million gallons of crude oil

Bubble Nucleation of Highly Superheated Water on Thin Film Platinum Films supported by SiN Membranes using a Low-Noise Bridge Circuit

December 1, 2014
Author(s)
Eric J. Ching, Michael J. Carrier, C. T. Avedisian, James R. Young, Bruce R. Land, Richard E. Cavicchi
This study describes the use of stress-minimized thin film platinum (Pt) membrane configurations (200 nm thick, 150 μm long, 10 μm wide) for promoting bubble nucleation of water near its superheat limit. The membrane designs consist of Pt films deposited

Characterization of Airborne Nanoparticle Released from Consumer Products

December 1, 2014
Author(s)
Andrew Persily, Liang Chung J. Lo, Steven J. Nabinger, Dustin Poppendieck, Li Piin Sung
Polymer and other coatings are commonly used to protect, enhance, or decorate wood, plastic and metal products used in homes and other buildings. Nanoparticles (i.e., particles having at least one dimension smaller than 100 nm) are increasingly being added

Cryptographic Module Validation Program (CMVP)

December 1, 2014
Author(s)
Apostol T. Vassilev, Larry Feldman, Gregory A. Witte
The Cryptographic Module Validation Program (CMVP) validates cryptographic modules for compliance with Federal Information Processing Standard (FIPS) Publication 140-2, Security Requirements for Cryptographic Modules, and other cryptography based standards

Dissipation due to pure spin current generated by spin pumping

December 1, 2014
Author(s)
Wayne M. Saslow, Tomohiro Taniguchi
Based on spin-dependent transport theory and thermodynamics, we develop a generalized theory of the Joule heating in the presence of a spin current. Along with the conventional Joule heating consisting of an electric current and electro-chemical potential
Displaying 19151 - 19175 of 74189
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