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Displaying 17651 - 17675 of 74303

Influence of Metal?MoS2 Interface on MoS2 Transistor Performance: Comparison of Ag and Ti Contacts

December 16, 2014
Author(s)
Hui H. Yuan, Guangjun Cheng, Lin You, Haitao Li, Hao Zhu, Wei Li, Joseph J. Kopanski, Yaw S. Obeng, Angela R. Hight Walker, David J. Gundlach, Curt A. Richter, D. E. Ioannou, Qiliang Li
In this work, we present a study of enhancing MoS2 transistor performance by using proper metal contact. We found that the on-state current of MoS2 field-effect transistors with 30 nm Au/ 30 nm Ag contacts is enhanced more than 60 times and the

Absolute line intensities for oxirane in the 11.4 micron spectral region.

December 15, 2014
Author(s)
Walter J. Lafferty, Jean-Marie Flaud, Fridolin Kwabia
Absolute individual line intensities of numerous transitions of the fundamental ν15, ν12 and ν5 bands of oxirane (ethylene oxide, cyc-C2H4O) have been measured in the 790-940 cm-1 region using seven high-resolution Fourier transform spectra recorded at 0

In-situ Temperature Calibration Capability for Dimensional Metrology

December 15, 2014
Author(s)
Prem K. Rachakonda, Daniel S. Sawyer, Balasubramanian Muralikrishnan, Christopher J. Blackburn, Craig M. Shakarji, Gregory F. Strouse, Steven D. Phillips
The Dimensional Metrology Group (DMG) at the National Institute of Standards and Technology (NIST) has developed a new in-situ temperature calibration system. This paper discusses the system components, an in-situ calibration procedure, the uncertainty

Metrics of Security

December 15, 2014
Author(s)
Yi Cheng, Julia Deng, Jason Li, Scott DeLoach, Anoop Singhal, Xinming Ou
Discussion of challenges and ways of improving Cyber Situational Awareness dominated our previous chapters. However, we have not yet touched on how to quantify any improvement we might achieve. Indeed, to get an accurate assessment of network security and

New x-ray measurements shed light on discrepancy between experiment and QED

December 15, 2014
Author(s)
Lawrence T. Hudson, C T. Chantler, A.T. Payne, M N. Kinnane, John D. Gillaspy, L F. Smale, Albert Henins, J A. Kimpton, E Takacs
Quantum Electro-Dynamics (QED) is the best tested theory of our physical world, yet significant disagreements have emerged between attempts to apply QED to exotic atomic systems. A recent 15 parts-per-million (ppm) experiment on muonic hydrogen, in which

Physical Properties of LiMn 2-x MxO 4 (M = Ni, Fe) Sol-Gel Nanopowders

December 15, 2014
Author(s)
E. Talik, L. Lipinska, A. Guzik, Pawel Zajdel, M. Michalska, M. Szubka, M. Kadziolka-Gawel, Rick L. Paul
The Pechini sol-gel method was applied to obtain LiMn 2-xT xO 4 (T=Ni, Fe; x = 0.1 to 0.5) nanopowders. Crystal and electronic structures, chemical composition and magnetic properties of the materials were characterized by X-ray diffraction, XPS, SEM/EDX

X-Ray microbeam measurements of long range internal stresses in commercial purity aluminum processed by multiple passes of equal-channel angular pressing

December 15, 2014
Author(s)
Lyle E. Levine, Thien Phan, I-Fang Lee, Jonathan Z. Tischler, Huang Yi, Alan G. Fox, Terrance G. Langdon, Mike Kassner
X-ray microbeam diffraction was used to measure long range internal stresses (LRIS) in the grain/subgrain interiors of commercial purity aluminum processed by equal-channel angular pressing for up to 8 passes. The LRIS values at +4.9o off the axial

Structure and Function of the Membrane Anchoring Self-Assembled Monolayers

December 14, 2014
Author(s)
David J. Vanderah, Tadas Ragaliauskas, Mindaugas Mickevicius, Mariya Jankunec, Gediminas Niaura, Gintaras Valincius, Bozena Rakovska
Structure of the self-assembled monolayers (SAMs) used to anchor phospholipid bilayers to surfaces affects the functional properties of the tethered bilayer membranes (tBLMs). SAMs of the same surface composition differing in the lateral distribution of

Device-Level Experimental Observations of NBTI-Induced Random Timing Jitter

December 13, 2014
Author(s)
Guangfan Jiao, Jiwu Lu, Jason Campbell, Jason Ryan, Kin P. Cheung, Chadwin D. Young, Gennadi Bersuker
This work utilizes device-level eye-diagram measurements to examine NBTI-induced changes in timing jitter at circuit speeds. The measured jitter is examined for a variety of ring-oscillator and pseudo-random gate patterns. The ring-oscillator patterns were

Behavior of Unrestrained and Restrained Steel Columns Adjacent to Localized Fire

December 12, 2014
Author(s)
Chao Zhang, John L. Gross, Therese P. McAllister, Guo-Qiang Li
Steel columns may be exposed to thermal radiation from localized burning of a fire source nearby. Current structural fire design methods are based on uniform heating and, therefore, uniform temperature conditions, and no practicable methods are provided to

Behavior of Unrestrained and Restrained Steel Columns Surrounded by Localized Fire

December 12, 2014
Author(s)
Chao Zhang, John L. Gross, Therese P. McAllister, Guo-Qiang Li
Real fires start from localized burning, and will not develop to flashover if in an open space or in large open-plan compartments. Temperatures of gas and exposed steel columns in localized fires are not uniform. Current structural fire design methods are

MECHANICS ANALYSIS OF MOLAR TOOTH SPLITTING

December 12, 2014
Author(s)
Amir Barani, Brian R. Lawn, Mark Bush, Herzl Chai
A model for the splitting of teeth from wedge loading of molar cusps from a round indenting object is presented. The model is developed in two parts: first, a simple 2D fracture mechanics configuration with the wedged tooth simulated by a compact tension

Natural Scene Statistics in Infrared Images

December 12, 2014
Author(s)
Nicholas G. Paulter Jr., Todd R. Goodall, Alan C. Bovik
Natural Scene Statistics (NSS) produces powerful perceptually relevant tools that have been highly successful in image quality analysis of visible light images. These NSS capture statistical regularities in the physical world and thus can be applicable to

PM Noise Measurement at W-Band

December 12, 2014
Author(s)
Archita Hati, Craig W. Nelson, David A. Howe
We present improved performance for a 92 - 96 GHz cross-spectrum phase modulated (PM) noise measurement system previously reported. The system is principally designed to measure amplifiers in pulsed mode with a duty cycle of 10% to 100% (CW) at a given

Quantitative Evidence for Organic Peroxy Radical Photochemistry

December 12, 2014
Author(s)
William S. McGivern, Joseph Klems
Quantitative evidence for the importance of alkyl peroxy photochemistry in the formation of secondary organic aerosol at 254 nm. Dodecanoic acid has been oxidized extensively in a flow cell by photolytically generated hydroxyl radicals to create particles

Short-Range Correlations in the Magnetic Ground State of Na 4 Ir 3 O 8

December 12, 2014
Author(s)
Rebecca Dally, Tom Hogan, Alex Amato, Chris Baines, Jose Rodriguez Rivera, Michael J. Graf, Stephen D. Wilson
The magnetic ground state of the J eff = 1/2 hyper-Kagome lattice in Na 4Ir 3O 8 is explored via combined bulk magnetization, muon spin relaxation, and neutron scattering measurements. A short-range, frozen, state comprised of quasi-static moments develops

Tunable Spin-Orbit Coupling via Strong Driving in Ultracold Atom Systems

December 12, 2014
Author(s)
Ian B. Spielman, Lindsay J. LeBlanc, Ross A. Williams, Matthew C. Beeler, Chunlei Qu, Ming Gong, Chuanwei Zhang
Spin-orbit coupling (SOC) is an essential ingredient in topological materials, conventional and quantum-gas based alike. Engineered spin-orbit coupling in ultracold atom systems unique in their experimental control and measurement opportunities provides a

Cryocooled 10 V Programmable Josephson Voltage Standard

December 11, 2014
Author(s)
Alain Rufenacht, Logan A. Howe, Anna E. Fox, Robert E. Schwall, Paul D. Dresselhaus, Charles J. Burroughs, Samuel P. Benz
Improvements in fabrication and packaging of our 10 V Programmable Josephson Voltage Standard circuits have enabled the successful operation of these devices on a cryocooler. Limited cooling power and temperature oscillations at the chip must not
Displaying 17651 - 17675 of 74303