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Displaying 18226 - 18250 of 73929

Close Correlation between Magnetic Properties and the Soft Phonon Mode of the Structural Transition in BaFe 2 A s 2 and SrFe 2 As 2

April 27, 2015
Author(s)
Daniel E Parshall, L. Pintschovius, J. L. Niedziela, J.-P. Castellan, D. Lamago, R. Mittal, Th. Wolf, D. Reznik
Parent compounds of Fe-based superconductors undergo a structural phase transition from a tetragonal to an orthorhombic structure. We investigated the temperature dependence of the frequencies of transverse acoustic (TA) phonons that extrapolate to the

Interface-State Capture Kinetics by Variable Duty Cycle Charge Pumping

April 27, 2015
Author(s)
Asahiko Matsuda, Jason T. Ryan, Jason P. Campbell, Kin P. Cheung
We demonstrated a new variant of the charge-pumping technique featuring varying duty cycle gate pulses to directly probe the interface-state carrier capture process in the time domain. This technique retains the exceptional sensitivity of charge pumping

Simulation of a Wind Driven Basement Fire - Riverdale Heights, MD

April 27, 2015
Author(s)
Craig G. Weinschenk, Kristopher Overholt, Daniel M. Madrzykowski
Fire Dynamics Simulator (FDS), which is a fire model that is developed and maintained by the Na- tional Institute of Standards and Technology (NIST), was used to provide insight into the dynamics of a fire that occurred on February 24, 2012, within a

Tower of Covering Arrays

April 25, 2015
Author(s)
Raghu N. Kacker, Jose Torres Jimenez
Covering arrays are combinatorial objects that have several practical applications, specially in the design of experiments for software and hardware testing. A covering array CA(N;t,k,v) of strength t and order v is an N×k array over Z v with the property

Computational Study of Trimer Self-Assembly and Fluid Phase Behavior

April 24, 2015
Author(s)
Harold W. Hatch, Vincent K. Shen, Jeetain Mittal
The fluid phase diagram of trimer particles composed of one central attractive bead and two repulsive beads was determined as a function of simple geometric parameters using flat-histogram Monte Carlo methods. A variety of self-assembled structures were

Magnetic Order in a-RuCl 3 : A Honeycomb-Lattice Quantum Magnet with Strong Spin-Orbit Coupling

April 24, 2015
Author(s)
J. A. Sears, M. Songvilay, K. W. Plumb, J. P. Clancy, Yiming Qiu, Yang Zhao, Daniel E. Parshall, Young-June Kim
We report magnetic and thermodynamic properties of single crystal α-RuCl 3, in which the Ru 3+ (4d 5) ion is in its low spin state and forms a honeycomb lattice. Two features are observed in both magnetic susceptibility and specific heat data; a sharp peak

Performance Measurement of Mobile Manipulators

April 24, 2015
Author(s)
Roger V. Bostelman, Tsai Hong Hong, Jeremy A. Marvel
This paper describes a concept for measuring the reproducible performance of mobile manipulators to be used for assembly or other similar tasks. An AGV with an onboard robot arm was programmed to repeatedly move to and stop at a novel, reconfigurable

Analysis of a Half-Scale Composite Floor System Test under Column Loss Scenarios

April 23, 2015
Author(s)
Joseph A. Main, Jonathan M. Weigand, Eric S. Johnson, Tim Francicso, Judy Liu, Jeffrey W. Berman, Larry A. Fahnestock
This paper describes modeling and analysis of a half-scale steel gravity frame system with composite concrete slab on steel deck that was constructed and tested at the University of Illinois under corner, edge, and interior column removal scenarios. For

Introducing Combinatorial Testing in a Large Organization

April 23, 2015
Author(s)
Jon Hagar, Thomas Wissink, D. Richard Kuhn, Raghu N. Kacker
A two-year study of eight pilot projects to introduce combinatorial testing in a large aerospace corporation found that the new methods were practical, significantly lowered development costs, and improved test coverage by 20 to 50 percent.

Measuring collected gas with microwave and acoustic resonances

April 23, 2015
Author(s)
Keith A. Gillis, James W. Schmidt, Michael R. Moldover, James B. Mehl
With calibrations of large flow meters in mind, we established the feasibility of determining the mass M of argon gas contained within a 0.3 m 3 commercially manufactured pressure vessel ("tank") with a relative standard uncertainty of u r(M) = 0.0016 at 0

New Steel Gravity Connection Details for Enhanced Integrity

April 23, 2015
Author(s)
Jonathan M. Weigand, Jeffrey W. Berman
Recent large-scale tests have found that Steel Gravity Framing Systems (SGFSs) with conventional connections were inadequate to support the integrity gravity load combinations under column removal scenarios. To address this issue, detailed connection

Rapid PCR of STR Markers: Applications to Human Identification

April 23, 2015
Author(s)
Peter Vallone, Erica Romsos
Multiplex PCR with fluorescently labeled primers has been an essential method for the amplification of short tandem repeats used in human identify testing. Within the STR workflow of extraction, quantitation, amplification, separation, and detection

Community Resilience of the Built Environment

April 22, 2015
Author(s)
Therese P. McAllister
Buildings, facilities, and infrastructure systems play a key role in the life of a community by supporting housing, business, government, industry, and other vital services. The concept of disaster resilience addresses the way that communities prepare for

Electron Spin Resonance Scanning Probe Spectroscopy for Ultra-Sensitive Biochemical Studies

April 22, 2015
Author(s)
Jason P. Campbell, Jason T. Ryan, Pragya R. Shrestha, Zhanglong Liu, Canute I. Vaz, Jihong Kim, Vasileia Georgiou, Kin P. Cheung
Electron spin resonance (ESR) spectroscopy’s affinity for detecting paramagnetic free radicals, or spins, has been increasingly employed to examine a large variety of biochemical interactions. Such paramagnetic species are broadly found in nature and can

Overview of the TREC 2014 Clinical Decision Support Track

April 22, 2015
Author(s)
Ellen M. Voorhees
The Text REtrieval Conference (TREC) Clinical Decision Support Track fosters research on systems that link electronic health records with information that is relevant for patient care. TREC 2014 is the initial year of the track. The focus of the first year

Speed of sound measurements and a fundamental equation of state for cyclopentane

April 22, 2015
Author(s)
Eric W. Lemmon, Holger Gedanitz, Maria J. Davila
The speed of sound in liquid cyclopentane has been measured in the temperature range from (258 to 353) K at pressures up to 30 MPa (42 data points) using a pulse-echo method with a double path type sensor. The expanded overall uncertainty (k = 2) in the

Time Dependent Driving Forces and the Kinetics of Tricalcium Silicate Hydration

April 22, 2015
Author(s)
Jeffrey W. Bullard, George W. Scherer, Jeffrey J. Thomas
Simulations of tricalcium silicate (C3S) hydration using a kinetic cellular automaton program, HydratiCA, indicate that the net rate depends both on C3S dissolution and on hydration product growth. Neither process can be considered the sole rate

Nondestructive measurement of the evolution of layer-specific mechanical properties in sub-10nm bilayer films

April 21, 2015
Author(s)
Justin M. Shaw, Kathleen Hoogeboom-Pot, Jorge Hernandez-Charpak, Henry Kapteyn, Margaret Murnane, Damiano Nardi
ABSTRACT: We use short-wavelength extreme-ultraviolet light to independently measure the mechanical properties of disparate layers within a bilayer film with single-monolayer sensitivity. We show that in Ni/Ta nanostructured systems, while their densities

Perfluorinated Alkyl Acids in Wildlife

April 21, 2015
Author(s)
Jessica L. Reiner, Benjamin J. Place
The first measurements of perfluorinated compounds (PFCs) in wildlife from the aqueous and terrestrial environment showed their ubiquitous presence. Since the initial studies in 2001 their presence, distribution, and fate in the environment has broadly

Pore Collapse and Regrowth in Silicon Electrodes for Rechargeable Batteries

April 21, 2015
Author(s)
Steven C. DeCaluwe, Bal Mukund NMN Dhar, Liwei Huang, Yuping He, Kaikun Yang, Jon P. Owejan, Yiping Zhao, A. Alec Talin, Joseph Dura, Howard Wang
Structure and composition changes of an alumina capped amorphous silicon (a-Si) thin-film anode in a lithium half-cell are measured, in opernado, by neutron reflectivity (NR) and electrochemical impedance spectroscopy. The a-Si anode's thickness expands
Displaying 18226 - 18250 of 73929
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