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Displaying 28026 - 28050 of 74219
Brad Conrad, Calvin Chan, Marsha A. Loth, John E. Anthony, David J. Gundlach
Organic semiconductors remain an active subject for device physics and material science because of their varied electrical properties and potential for low-cost, high-throughput roll-to-roll processing. Several high-mobility oligomers, such as pentacene
High precision Hylleraas-Configuration Interaction (Hy-CI) method variational calculations are reported for the 2 doublet S ground state of neutral lithium. The nonrelativistic energy is calculated to be -7.4780 6032 3451 9 hartree, demonstrating that the
Jason J. Gorman, Craig D. McGray, Richard A. Allen
Recent advances in the design and fabrication of microelectromechanical systems (MEMS) have enabled the development of mobile microrobots that can autonomously navigate and manipulate in controlled environments. It is expected that this technology will be
The National Institute of Standards and Technology (NIST) maintains one of the world s most accurate and stable time scales, UTC(NIST), as well as the NIST-F1 cesium fountain, the primary frequency standard for the United States. These standards are
Lawrence T. Hudson, L.M Chen, W.M. Wang, M. Kando, F Liu, X.X. Lin, J.L Ma, Y.T. Li, S.V. Bulanvo, T. Tajima, Y. Kato, Z.M. Sheng, J Zhang
In this report we address the current situation of laser-driven hard X-ray sources for imaging applications,especially the saturation of X-ray conversion efficiency and the serious impact upon imaging quality.By employing high contrast laser pulses,the
Thuy Chastek, Aniket Wadajkar, Kytai T. Nguyen, Steven Hudson, Thomas Q. Chastek
We report on the synthesis of monodisperse thermally responsive poly(N-isopropylacrylamide) (PNIPAM) nanoparticle hydrogels (i.e., microgels). PNIPAM microgels were synthesized using Pluronic surfactants (L64, P65, P85, and F127) to increase their
There is a great need for high accurate, truly-3D metrology solutions that can be used for analysis of high aspect ratio features such as through-silicon-vias (TSVs). In this presentation we propose evaluating the viability of the newly developed through
Robert D. Chirico, Andrei F. Kazakov, William V. Steele
Measurements leading to the calculation of thermodynamic properties for phenazine (Chemical Abstracts registry number [92-82-0]) in the ideal-gas state are reported. Experimental methods included adiabatic heat-capacity calorimetry, inclined-piston
Robert D. Chirico, Andrei F. Kazakov, William V. Steele
Measurements leading to the calculation of standard entropies for 1,10-phenanthroline (Chemical Abstracts registry number [66-71-7]) in the crystal, liquid, and ideal-gas state are reported. Experimental methods were adiabatic heat-capacity calorimetry and
Willie E. May, Richard R. Cavanagh, Dianne L. Poster, Michael D. Amos
CSTL is entrusted with building, sustaining, and maximizing the chemical measurement system that is criticial to chemical technological innovation, economic competitiveness and new job growth for the benefit of the Nation.
This chapter discusses the role of air infiltration and ventilation in building moisture transport. While water vapor diffusion can be a very important moisture transport mechanism, as discussed in other chapters, bulk air movement via infiltration and
Kwang Jun Lee, Omer Akin, Burcu Akinci, James Garrett, Steven T. Bushby
This paper presents the results of initial work in developing an ontology for improving information exchange and automation in building system commissioning practices. In our previous research dealing with the derivation of product models from building
Ultra Wide-Band (UWB) is a favorable technology for wearable medical sensors that monitor vital signs and other health-related information. Efficient transceiver design requires in-depth understanding of the propagation media which in this case is the
Thomas J. Bruno, Lisa S. Ott, Tara M. Lovestead, Marcia L. Huber
The analysis of complex fluids such as crude oils, fuels, vegetable oils and mixed waste streams poses significant challenges arising primarily from the multiplicity of components, the different properties of the components (polarity, polarizability, etc)
Bruce S. MacDonald, John L. Molloy, Stefan D. Leigh, William R. Kelly, Andrew L. Rukhin
Interval-repeatability (Ir) is a statistic that users of certified reference materials (CRMs) may employ as a quality control check to identify incorrectly prepared working standards or nonlinear instrument response over a targeted concentration interval
Jennifer A. Taylor, Franklyn J. Quinlan, Scott A. Diddams
Very low-noise microwave signals are desirable for many state-of-the-art applications, including many types of radar and imaging systems. However, even state-of-the-art rf oscillator technology for producing signals into the tens of gigahertz range does
The stability of differential delays between Global Navigation Satellite receivers is critical for time and frequency transfer. We study the limit of this transfer between two specific receivers from the study of data taken from these receivers while they
Stefania Romisch, Thomas E. Parker, Steven R. Jefferts
A novel, all-digital phase measurement system, to be utilized as part of the NIST Time Scale at NIST in Boulder, CO is presented. The system is used to compare output signals from several commercial atomic frequency standards: the phase differences between
A popular scheme for achieving low phase noise across a large range of offset frequencies is to employ an oscillator at an output frequency with low far-from-carrier noise that is phase-locked to a reference that has low close-to-carrier noise. We
Paul D. Kunz, Thomas P. Heavner, Steven R. Jefferts
We are developing a transportable laser-cooled rubidium (Rb) atomic fountain frequency standard. We have a complete optical package, and have recently shown cooled, launched, and detected atoms. Additionally, a new physics package has been designed and is
Victor S. Zhang, Thomas E. Parker, Demetrios Matsakis, Joseph Achkar, Daniele Rovera, Dirk Piester, Andreas Bauch, Luca Lorini
The Ku-band transatlantic and Europe to Europe two-way satellite time and frequency transfer (TWSTFT) operations used the 2.5 MChip/s pseudo-random codes with 3.5 MHz bandwidth until the end of July, 2009. The cost of TWSTFT operation is associated with
Lawrence P. Cook, Richard E. Cavicchi, Nabil Bassim, Susie Eustis, Winnie Wong-Ng, Igor Levin, Ursula R. Kattner, Carelyn E. Campbell, Christopher B. Montgomery, William F. Egelhoff Jr., Mark D. Vaudin
We have investigated multilayer and bilayer Ni/Si thin films by nano-differential scanning calorimetry (DSC) at ultra rapid scan rates, in a temperature-time regime not accessible with conventional apparatus. DSC experiments were completed at slower scan