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Displaying 29651 - 29675 of 74303

Virtual-Real Quantum Interference in a Semiconductor System

October 16, 2008
Author(s)
H Ahn, S B. Choe, D S. Kim, J M. Shacklette, Y S. Lim
Probabability amplitude in the upper state can be induced by the off-resonant, virtual excitations as well as by the resonant, real excitations. Bytwo-color pulse shaping, we simultaneously create virtual and real amplitudes for excitons in GaAs quantum

Visualization Technique for Uncertainty Budgets: Onion Charts

October 16, 2008
Author(s)
Kenneth W. Pratt, David L. Duewer
A concise graphical depiction, the onion chart, is described for presenting uncertainty budgets for any measurand, y, having a set of component variances, ui2(y). The onion chart consists of a concentric series of rings. Each ring is constructed from the

Vortices, Antivortices and Superfluid Shells Separating Mott-Insulating Regions

October 16, 2008
Author(s)
Kaushik Mitra, Carl J. Williams, Carlos Sa de Melo
Atomic or molecular bosons in harmonically confined optical lattices are found to exhibit a wedding cake structure consisting of insulating (Mott) and superfluid shells. It is found that the order parameter equation in the superfluid regions is not of the

Water Determination

October 16, 2008
Author(s)
S A. Margolis, Peter H. Huang
No abstract required.

Water Dissociation in the Presence of Metal Ions

October 16, 2008
Author(s)
Orkid Coskuner, Emily Jarvis, Thomas C. Allison
Hydrated metal ions are important in a variety of biological and environmental systems, yet a comprehensive picture of the dynamic local environment associated with these ions remains elusive. We report ab initio molecular dynamics of water around Al3+

Wavelength--Shift Fluorescent Probes for Monitoring of Polymerization

October 16, 2008
Author(s)
Francis W. Wang, R E. Lowry
The feasibility of using wavelength-shift fluorescent probes for cure monitoring of an epoxy resin and an acrylic resin was evaluated. 4-(N,N-dihexylaminostyryl)-4 -pyridinium propylsulfonate (DHASP-PS), as well as each of other wavelength-shift

Wavelengths of Six Times Ionized Germanium, GeVII

October 16, 2008
Author(s)
Larissa Podobedova, A N. Ryabtsev
The compilation of the wavelengths of the GeVII spectra is carried out for the NIST Atomic Spectra Data Base on the World Wide Web. This compilation is based on our previous analyses of the germanium spectra: the 3d 8-3d 7 4p transition array in the range

Well-Ordered Polymer Melts with 5 nm Lamellar Domains from Blends of a Disordered Block Copolymer and a Selectively Associating Homopolymer of Low or High Molar Mass

October 16, 2008
Author(s)
Vijay Tirumala, August W. Bosse, Eric K. Lin, Vikram Daga, Alvin Romang, Jan Ilavsky, J J. Watkins
The use of short chain block copolymer melts as nanostructured templates for sub-10 nm domains is often limited by their low segregation strength (N). Since increasing molar mass to strengthen segregation also increases the interdomain spacing of block

Wetting-Dewetting Transition Line in Thin Polystyrene Films

October 16, 2008
Author(s)
K M. Ashley, D T. Raghavan, Jack F. Douglas, Alamgir Karim
Thin polymeric films are increasingly being utilized in diverse technological applications and it is crucial to have a reliable method to characterize the stability of these films against dewetting. The parameter space that influences the dewetting of thin

Why and When Should One Calibrate a Measurement System

October 16, 2008
Author(s)
Raghu N. Kacker
A measurement without its uncertainty is not adequate. The stated uncertainty ceases to be valid when the measurement system goes out of calibration. A conventional re-calibration interval may not be optimal for all usage conditions. The cost of re

Why Is Minkowski Spacetime Non-Euclidean?

October 16, 2008
Author(s)
J M. Cronkhite
The geometry of Minkowski spacetime is pseudo-Euclidean, thanks to the time component term being negative in the expression for the four dimensional interval. This fact renders spacetime geometry unintuitive and extremely difficult to visualize. I present

XRD Rietveld Simulations Y 2 O 3 - ZrO 2 Phases

October 16, 2008
Author(s)
Jennifer R. Verkouteren, Joseph M. Conny
X-ray diffraction patterns of tetragonal and cubic yttria-stabilized were simulated to test the capability of Rietveld refinement to accurately seperate the phases. The effects of peak broadening and different c/a ratios on the refinement results were

Young Modulus of a thin plate in the through-thickness direction

October 16, 2008
Author(s)
Sudook A. Kim, H M. Ledbetter
We give a new approach to obtain the through-thickness-direction along the Young modulus of a thin orthotropic plate. The method minimizes errors because eight of nine measurments are made along principal directions. To verify the method, we used a

Contact resonance atomic force microscopy for viscoelasticity

October 15, 2008
Author(s)
Donna C. Hurley, Philip Yuya, J Turner
We present a quantitative method for determining the viscoelastic properties of materials with nanometer spatial resolution. The approach is based on the atomic force acoustic microscopy (AFAM) technique that involves the resonant frequencies of the AFM

Directional Antenna for Multipath Ad Hoc Routing

October 15, 2008
Author(s)
Hamid Gharavi, Bin Hu
Multipath routing can be effectively used to maximize the utilization of network resources for real-time traffic. In mobile ad-hoc network environments, this approach can suffer from co-channel interference due to the simultaneous transmission of packets
Displaying 29651 - 29675 of 74303