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Displaying 3651 - 3675 of 74079

Stability of Global Entanglement in Thermal States of Spin Chains

October 12, 2021
Author(s)
G K. Brennen, Stephen Bullock
We investigate the entanglement properties of a one dimensional chain of spin qubits coupled via nearest neighbor interactions. The entanglement measure used is the $n$-concurrence, which is distinct from other measures on spin chains such as bipartite

Stability of Precision Diamond Turning Processes That Use Round Nosed Tools

October 12, 2021
Author(s)
David E. Gilsinn, Matthew A. Davies, B Balachandran
A system of retarded differential equations model is developed for a diamond-turning process with chip area cut by a round nosed tool. The results are presented in the form of stability charts that are found to be perturbed forms of those obtained for

Stable and Robust Polymer Nanotubes Stretched From Polymersomes

October 12, 2021
Author(s)
Joseph E. Reiner, J M. Wells, Rani B. Kishore, Candace Pfefferkorn, Kristian Helmerson
We create long polymer nanotubes by directly pulling on the membrane of polymersomes using either optical tweezers or a micropipette. The polymersomes are composed of amphiphilic diblock copolymers and the nanotubes formed have an aqueous core. We

Standard Reference Photometer for the Assay of Ozone in Calibration Atmospheres

October 12, 2021
Author(s)
R J. Paur, A M. Bass, James E. Norris, T J. Buckley
A photometric instrument for the assay of ozone from 0 ppbv to 1000 ppbv in calibration atmospheres as been designed, constructed, and evaluated. The absorption cross-section of ozone at 254 nm (HG line) is the major component of uncertainty of the

Stoichiometry and Phase Composition of MOCVD Barium Titanate Films

October 12, 2021
Author(s)
Charles E. Bouldin, Joseph Woicik, Bruce Ravel, Debra Kaiser, Mark D. Vaudin
X-ray absorption fine structure (XAFS), x-ray diffraction (XRD) and x-ray fluorescence (XRF) have been used to study the stoichiometry and phase composition of thin (approximately equal to} 1 micron) films deposited on MgO substrates. Deposition

Strain and Spin-Orbit Effects in Self-Assembled Quantum Dots

October 12, 2021
Author(s)
M Zielinski, W Jaskolski, Javier Aizpurua, Garnett W. Bryant
The effects of strain and spin-orbit interaction in self-assembled lens-shaped InAs/GaAs quantum dots are investigated. Calculations are performed with empirical tight-binding theory supplemented by the valence force field method to account for effects of

Strength Evaluation on a Composite Marine Propeller Blade

October 12, 2021
Author(s)
H J. Lin, J J. Lin, Tze-Jer Chuang
The strength of a composite propeller blade is evaluated by performing a nonlinear hydro-elastic analysis. The finite element method, lifting surface theory, least square method, equilibrium equation and Hashin failure criteria are employed for the

Structural Alterations in the DNA of Stroma and Epithelium From the Female Breast

October 12, 2021
Author(s)
Donald C. Malins, Katie M. Anderson, Pawel Jaruga, Callie R. Ramsey, Naomi K. Gilman, Virginia M. Green, Steven W. Rostad, Joanne T. Emerman, M. Dizdaroglu
Reciprocal interactions between the stroma and epithelium are considered to be intimately associated with the development of breast cancer. In studies of whole breast tissues, a keen interest exists in the occurrence of the mutagenic DNA lesions 8-hydroxy

Structure and Crystal Chemistry of M 0.5 Ta 0.5 B (M = Ti, Zr, and Hf)

October 12, 2021
Author(s)
I Talmy, J Zaykoski, J A. Kudak, Winnie Wong-Ng
During the development of refractory composites (cermets) combining MB2 (M=Ti, Zr, or Hf) ceramics and Ta metal, three new phases of compositions M0.5Ta0.5B were discovered. Preliminary determination of lattice parameters using x-ray powder diffraction

Structure and Reactivity of the Hydrated Hematite (0001) Surface

October 12, 2021
Author(s)
T P. Trainor, Anne M. Chaka, P J. Eng, M Newville, G A. Waychunas, J G. Catalano, G E. Brown
Hematite (alpha-Fe 2 O 3 ) is significantly more reactive to water and metal ions than its isostructure corundum (alpha-Al 2 O 3u) under environmental conditions. However, the reason for this difference is not understood. Using crystal truncation rod

Study of Isochoric Specific Heat Capacity Measurements for Liquid Isobutane

October 12, 2021
Author(s)
Hiroyuki Miyamoto, Hiroshi Kitajima, Noboru Kagawa, Joe W. Magee, Seizo Tsuruno, Koichi Watanabe
Isobutane is one of the most promising alternative refrigerants because of its zero ODP and negligible GWP. It can be used not only as a pure component but also as a component of binary or ternary mixture refrigerants. To design and evaluate cycle

Study of Photodegradation of Epoxy Polymer by Using Slow Positron Annihilation Spectroscopy

October 12, 2021
Author(s)
R Zhang, Xiaohong Gu, H Chen, J Zhang, Y Li, Tinh Nguyen, T C. Sandreczki, Y C. Jean
Slow positron annihilation spectroscopy (SPAS) has been used to study the early stage of epoxy photodegradation. Spin-coated samples of a crosslinked epoxy were prepared by stoichiometrically mixing a diglycidyl ether of bisphenol A epoxy resin with 1,3

Subsolidus Phase Relationships in the AO-AI 2 O 3 -Nb 2 O 5 (A=Ca, Sr) Systems

October 12, 2021
Author(s)
Julia Y. Chan, Wilma Feb-Ayala, J. M. Loezos, L D. Rotter, Lyle E. Levine, Richard G. Geyer
Dielectric ceramics for wireless communications exhibiting modest permittivity, high quality factor (Q), and near-zero temperature coefficient are needed for high-frequency, high power applications. Efforts are in progress to replace Ta 2O 5-based ceramics

Surface Analytical Kinetic Studies of Noise-Generating Electron Transfer Processes: In Vivo Sensing Properties of Nanoengineered Organic Cardiac Pacing Electrodes in Living Heart

October 12, 2021
Author(s)
H A. Chou, P DaeGynn, David J. Vanderah, M Ovadia
Novel organic cardiac electrode candidates enhanced by self-assembled monolayers (SAMs) are examined by varying rate cyclic voltammogram and impedance spectroscopy with hexacoordinated [Fe(CN)6]-3 as the probe for their susceptibility to Faradaic current
Displaying 3651 - 3675 of 74079