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Search Publications

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Displaying 3576 - 3600 of 74309

Entanglement Dynamics in 1D Quantum Cellular Automata

October 12, 2021
Author(s)
G K. Brennen, J E. Williams
Several proposed schemes for the physical realization of a quantum computer consist of qubits arranged in a cellular array. In the quantum circuit model of quantum computation, an often complex series of two-qubit gate operations is required between

Enthalpies of Formation of Dibutyl Phthalate and Methyl 4-Hydroxybenzoate

October 12, 2021
Author(s)
Yu V. Maksimuk, Kvetoslav Ruzicka, Vladimir Diky
Enthalpies of formulation of liquid dibutyl phthalate (DBP, -864.67+4.77 kJ*mol -1) and crystalline methyl 4-hydroxybenzoate (4-MHB, -562.20+2.29 kJ*mol -1) were determined by combustion calorimety. Relations of these values to the structures of the

Environmentally Enhanced Crack Growth in AlN

October 12, 2021
Author(s)
Roy W. Rice, C C. Wu, K R. McKinney, Stephen W. Freiman, L E. Dolhert, J H. Enloe
Three tests: (1) dynamic fatigue; (2) flexure strength, and (3) direct, double-cantilever beam stress intensity-crack velocity measurements carried out in air (22 C) and liquid nitrogen (-196 C) all showed that dense sintered AlN undergoes slow crack

Evaluation of Dental Restorative Composites Containing POSS-Methacrylate Monomers

October 12, 2021
Author(s)
H F. Fong, H Fong, Glenn M. Flaim, Sabine H. Dickens
We have combined confocal optical coherence (OCM) and confocal fluorescence (CFM) microscopies to gather simultaneous structural and functional information on tissue engineered products in a registered fashion. In this work, we present the design and

Evaluation of Microstructure of BaTiO 3 -Polymer Composites by Confocal Microscopy

October 12, 2021
Author(s)
C. K. Chiang, Li Piin Sung, R Popielarz, Jan Obrzut
Laser scanning confocal microscopy has been applied to examine the distribution of BaTiO3 particles in ceramic-polymer composite films. The thin-slice images of the thickness of the order of one micron allowed us to visualize the micron-size particles and

Excited Thomas-Efimov Levels in Ultracold Gases

October 12, 2021
Author(s)
M D. Lee, T Koehler, Paul S. Julienne
Since the early days of quantum physics, the complex behavior of three interacting particles has been the subject of numerous experimental and theoretical studies. In a recent Letter to Nature, Kraemer et al. [Nature (London) 440, 315 (2006)] report on

Exciton-Plasmon Interaction and Hybrid Excitons in Semiconductor-Metal Nanoparticle Assemblies

October 12, 2021
Author(s)
A O. Govorov, Garnett W. Bryant, Wei Zhang, T Skieni, J Lee, N A. Kotov, Joseph M. Slocik, Rajesh R. Naik
We describe physical properties of excitons in hybrid complexes composed of semiconductor and metal nanoparticles. The interaction between individual nanoparticles is revealed as an enhancement or suppression of emission. Enhanced emission comes from

Extended Abstract: Interfacial Scattering of Hot Electrons in Ultra-Thin Magnetic Films

October 12, 2021
Author(s)
R P. Lu, B A. Morgan, K L. Kavanagh, Cedric J. Powell, P J. Chen, F Serpa, William F. Egelhoff Jr.
In the emerging field of Spintronics the transport of hot electrons through magnetic thin films seems destined to play a key role. To help understand such transport, we have used ballistic electron emission microscopy (BEEM) to measure hot-electron

Extracellular and Intracellular Chorismate Mutases From Mycobacterium tuberculosis H 37 R v : Characterization of the Hypothetical Gene Products Rv1885c and Rv0948c

October 12, 2021
Author(s)
Sung Kim, Sathyavelu K. Reddy, G B. Vasquez, B C. Nelson, A M. Davis, S. Patterson, Prasad T. Reddy
Two ORFs Rv1885c and Rv0948c from the genome of Mycobacterium tuberculsosis H37Rv were identified as putative chorismate mutases. We reported earlier that Rv1885c is indeed a chorismate mutase (CM) with a 33 amino acid cleavable signal sequence in a

Extreme Anisotropy of Diffuse Interfaces in Crystals

October 12, 2021
Author(s)
N D. Alikakos, P W. Bates, John W. Cahn, P C. Fife, G Fusco, G B. Tanoglu
We investigate a model of anisotropic diffuse interfaces in ordered FCC crystals introduced recently by Braun et al, focussing on parametric conditions which give extreme anisotropy. For a reduced model, we prove existence and stability of plane wave

Feasibility Study of the Use of Frozen Human Sera in Split-Sample Comparison of Immunoassays With Reference Measurement Procedures for Total Thyroxine and Total Triiodothyronine Measurement

October 12, 2021
Author(s)
Linda M. Thienpont, Katleen Van Uytfanghe, J Marriot, Y Tokura, Lothar Siekmann, Anja Kessler, David M. Bunk, Susan Tai
Background: Diagnostic manufacturers must ensure/document metrologically traceable assays. Here we report on a feasibility study that investigated the use of a split-sample comparison with processed, frozen single-donation sera assigned with target values

Feasibiliy and Fidelity of Data Exchange Through IFC for Building Commissioning

October 12, 2021
Author(s)
Hongjun Wang, Burcu Akinci, J H. Garrett, K A. Reed
The building commissioning (BC) process ensures that the various interacting systems in a building are properly installed and operating. It is a process requiring extensive data exchange among different participants across multiple project phases. The

Ferroics: Magnetic-Compass Lattice and Optical Phonon Dispersions of Dipolar Crystals

October 12, 2021
Author(s)
Takeshi Nishimatsu, U Waghmare, Yoshiyuki Kawazoe, Benjamin P. Burton, Kazutaka Nagao, N. Saito
We report a simple safe and attractive pedagogic demonstration with magnetic compasses that facilitates an intuitive understanding of the concept that ferromagnetism and ferroelectricity do not result from dipole-dipole interactions alone. Phonon

Ferromagnetic Resonance Line Width in Inhomogeneous Thin Films

October 12, 2021
Author(s)
Robert McMichael, A B. Kunz, D J. Twisselmann
The dynamic properties of magnetic materials are important for magnetic data storage. The primary measurement technique for understanding magnetization damping is ferromagnetic resonance line width. Because materials inhomogeneities increase experimental

Fifth Annual Report on Federal Agency Use of Voluntary Consensus Standards

October 12, 2021
Author(s)
K L. McIntyre, M B. Moore
Document is the Annual Report on Federal Agency Use of Voluntary Consensus Standards required to be submitted by NIST the office of Management Budget (OMB) under the National Technology Transfer and Advancement Act and OMB Circular A-119. It contains a

Final Report of Key Comparison CCQM-K4 (Ethanol in Air)

October 12, 2021
Author(s)
M J. Milton, C Brookes, A Marschal, Franklin R. Guenther, George C. Rhoderick, D E. Leer, L W. Zhen, C Takahashi, E Deak, Y A. Kustikov
This key comparison involved primary standards of ethanol in air maintained at eight laboratories. The nominal amount fraction of the standards used for the comparison was 120 mmol/mol which is typical of the levels used to calibrate evidential breath

Final Report of the SIM 60 Co Air-Kerma Comparison (KCDB Entry SIM.RI (I)-K1)

October 12, 2021
Author(s)
C K. Ross, K Shortt, M Saravi, A Meghzifene, V M. Tovar, R A. Barbosa, C N. da Silva, F Gutt, Stephen M. Seltzer
Transfer chambers were used to compare the standards for 60Co air kerma maintained by seven laboratories. Six of the laboratories were members of the Sistema Interamericano de Metrolog a (SIM) regional metrological organization while the seventh was the

Final Report on CIPM Key Comparison of Multiples and Submultiples of the Kilogram (CCM.M-K2)

October 12, 2021
Author(s)
L O. Becerra, W Bich, N Bignell, G D. Chapman, J.-H. Chung, Stuart Davidson, M Glaser, A Gosset, Zeina J. Kubarych, W G. Lee, A Ooiwa, P Richard, R Spurny, A Torino, J Verbeek, L Q. Zhang
A key comparison concerning mass determination of five mass standards has been carried out under the auspices of the Comite Consultatif pour a la Mase et les Grandeurs Apparantees (CCM) from March 1998 to March 1999. The nominal values of the mass

First Results With Small Cam-Driven Absolute Gravimeter

October 12, 2021
Author(s)
A L. Vitouchkine, J E. Faller
We describe the design and first results of a cam-driven portable absolute gravinieter. The cam-based design of a dropper allows us to builda compact system that uses 20 mm of free-fall for the measurement. The instrument drops a test mass 200 times a
Displaying 3576 - 3600 of 74309