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Displaying 15026 - 15050 of 74203

Sympathetic Ground State Cooling and Time-dilation Shifts in an 27Al+ Optical Clock

February 3, 2017
Author(s)
Jwo-Sy Chen, Samuel M. Brewer, David B. Hume, Chin-Wen Chou, David J. Wineland, David R. Leibrandt
We report Raman sideband cooling of 25Mg+ to sympathetically cool the secular modes of motion in a 25Mg+-27Al+ two-ion pair to near the three-dimensional (3D) ground state. The evolution of the Fock state distributions during the cooling process is studied

An electrically driven spin qubit based on valley mixing

February 2, 2017
Author(s)
wister huang, Neil M. Zimmerman, Andrew S. Dzurak, Dimitrie Culcer
The electrical control of single spin qubits based on semiconductor quantum dots is of great interest for scalable quantum computing since electric elds are much easier to produce and spatially focus than magnetic elds. Here we outline the mechanism for a

Biophysical Characterization of Functionalized Titania Nanoparticles and Their Application in Dental Adhesives

February 2, 2017
Author(s)
Jirun Sun, Elijah Petersen, Stephanie S. Watson, Christopher Sims, Alexander Kassman, Stanislav Frukhtbeyn, Drago Skrtic, Meryem T. Ok, Deborah Jacobs, Qiang Ye, Bryant C. Nelson
It is demonstrated that carboxylic acid-functionalized titanium dioxide (TiO2) NPs produce significantly higher levels of reactive oxygen species (ROS) after visible light irradiation (400-800 nm, 1600 mW/cm2) in comparison to nonfunctionalized TiO2 NPs

Generating Wind-Driven Firebrand Showers Characteristic of Burning Structures

February 1, 2017
Author(s)
Samuel L. Manzello, Sayaka Suzuki
Firebrands are a significant source leading to structures ignited and lost in large outdoor fires, such as Wildland–Urban Interface (WUI) fires, a large international problem, and urban fires, common in Japan. Sadly, hardly any information is available

Neutron Radiography Measurement of Salt Solution Absorption in Mortar

February 1, 2017
Author(s)
Catherine Lucero, Robert Spragg, Dale P. Bentz, Daniel S. Hussey, David L. Jacobson, Jason Weiss
A portion of the concrete pavements in the US have recently been observed to have premature joint deterioration. While this damage has been attributed to a wide variety of potential factors, it is hypothesized that one component of this damage can be

Toward Integrating Distributed Energy Resources and Storage Devices in the Smart Grid

February 1, 2017
Author(s)
Guobin Xu, Wei Yu, David W. Griffith, Nada T. Golmie, Paul Moulema
The smart grid, as one of typical applications supported by Internet of Things, denoted as a re-engineering and a modernization of the traditional power grid, aims to provide reliable, secure, and efficient energy transmission and distribution to consumers

Ultrafast modulation of x-ray absorption by coherent phonon excitations

February 1, 2017
Author(s)
Eric L. Shirley, Jannick Weisshaupt, Michael Woerner, Marc J. Vrakking, Thomas Elsaesser, Andreas Borgschulte
X-ray absorption in solids promotes an electron from an atomic core level to the conduction band states, and near-edge spectra structure gives insight into local atomic geometry and chemical bonding effects. Based on a novel implementation of femtosecond x

Vibrational Properties of b-KSiH 3 and b-RbSiH 3 : A Combined Raman and Inelastic Neutron Scattering Study

February 1, 2017
Author(s)
Janos Mink, Yuan-Chih Lin, Maths Karlsson, Carin Osterberg, Terrence J. Udovic, Henrik Fahlquist, Ulrich Haussermann
The hydrogen storage materials ASiH 3 (A=K, Rb) represent complex metal hydrides built from metal cations and pyramidal SiH 3- ions. At room temperature, SiH 3-moieties are randomly oriented because of dynamical disorder (α-modifications). At temperatures

A Category Theoretic Approach to Modeling and Analysis Using Music as a Case Study

January 31, 2017
Author(s)
Sarala Padi, Spencer J. Breiner, Eswaran Subrahmanian, Ram D. Sriram
The goal of this paper is to provide a category theoretic ontology for the creation of a collaborative platform where it allows group of people to share or use the knowledge in a domain. We use Indian music as a case study to demonstrate the power of

A Clock Ensemble Using Only Active Hydrogen Masers

January 31, 2017
Author(s)
Thomas E. Parker, Stefania Romisch
The current real-time timescale at NIST, AT1, as well as the post-processed scale TP162, both contain hydrogen masers and commercial cesium frequency standards. The cesium standards are much nosier in the short term than the hydrogen masers and

A Study on Using the SDR Receiver for the Europe-Europe and Transatlantic TWSTFT Links

January 31, 2017
Author(s)
Victor S. Zhang, Thomas E. Parker, Joseph Achkar, Dirk Piester, Yi-Jiun Huang, Shinn-Yan Lin, Zhiheng Jiang
The BIPM and the CCTF Working Group on TWSTFT have stimulated a pilot study on using software defined radio (SDR) receivers for TWSTFT in the framework of the realization of International Atomic Time (TAI). The SDR receivers based on a software developed

Accurate TWSTFT time transfer with indirect links

January 31, 2017
Author(s)
Victor S. Zhang, Zhiheng Jiang, Thomas E. Parker, Jian Yao, Yi-Jiun Huang, Shinn-Yan Lin
The conventional wisdom suggests a direct Two-Way Satellite Time and Frequency Transfer (TWSTFT or TW) time link should result in a smaller uncertainty than that of an indirect TW link over the same baseline [12]. This is why all Coordinated Universal Time

Impact of UV irradiation on multiwall carbon nanotubes in nanocomposites: formation of entangled surface layer and mechanisms of release resistance

January 31, 2017
Author(s)
Tinh Nguyen, Elijah J. Petersen, Bastien T. Pellegrin, Justin M. Gorham, Thomas F. Lam, Minhua Zhao, Li Piin Sung
Carbon nanotubes (CNTs) are increasingly used in consumer and structural polymeric products to enhance a variety of properties. Under weathering, the polymer matrix will degrade and the nanofillers will potentially be released from the products, which
Displaying 15026 - 15050 of 74203
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