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Displaying 3826 - 3850 of 74647

Issues and Applications in Ultra-Sensitive Molecular Spectroscopy

October 12, 2021
Author(s)
C Ishibashi, Jun Ye, John L. Hall
We present a systematic analysis of ultra-sensitive molecular detection methods based on an optical cavity and frequency modulationspectroscopy. Our goal is towards the improvement of the limiting attainable performance by the choice of optical

Jamming in Carbon Nanotube Suspensions

October 12, 2021
Author(s)
D J. Fry, Haonan Wang, Erik K. Hobbie
The 'phase diagram' of a non-Brownian carbon nanotube suspension is measured as a function of concentration, shear stress, and geometrical confinement. We observe a hierarchy of flow-induced structure, including dispersed 'nematics', isolated, periodic and

Kinetic Theory of a Spin-1/2 Bose-Condensed Gas

October 12, 2021
Author(s)
T Nikuni, J E. Williams
We derive a kinetic theory for a spin-1/2 Bose-condensed gas of two-level atoms at finite temperatures. The condensate dynamics is described by a generalized Gross-Pitaevskii equaiton for the two-component spinor order parameter, which includes the

Laboratory and Field Test Results for an Ultrasonic Applied Stress Measurement Instument

October 12, 2021
Author(s)
P A. Fuchs, A V. Clark, M G. Lozev, U Halabe, P Klinkhachorn, S Petro, H GangaRao
The measurement of applied stress on bridges can provide valuble information on the condition of the structure. The conventional technique for applied stress measurement is with a strain gage. However, strain gages can be time consuming to install because

Large Negative Poisson's Ratio for SrTiO3 Thin Films Grown on Si(001

October 12, 2021
Author(s)
F S. Aguirre-Tostado, A Herrera-Gomez, Joseph Woicik, R Droopad, Z Yu, D G. Schlom, E Karapetrova, P Pianetta, C S. Hellberg
The driving force of the semiconductor industry to integrate thin transition-metal oxides with Si transistor technology has led to the development of SrTiO3 thin-film growth on Si(001). As SrTiO3 represents a large class of oxides with the perovskite

Laser Based Angle-Resolved Photoemission, the Sudden Approximation and Quasiparticle-Like Spectral Peaks in Bi 2 Sr 2 Cu 2 O 8 +D

October 12, 2021
Author(s)
j D. Koralek, Jack F. Douglas, N C. Plumb, Z Sun, A V. Fedorov, M M. Murnane, H C. Kapteyn, Steven T. Cundiff, Y Aiura, K Oka, H. Eisaki, D S. Dessau
A new low photon energy regime of angle-resolved photoemission spectroscopy is accessed with lasers and used to study the hight T c superconductor Bid2^CaCu 2O 8d+^delta. The low energy increases bulk sensitivity, reduces background, and improves

Layer Perfection in Ultrathin, MOVPE-Grown InAs Layers Buried in GaAs(001) Studied by X-Ray Standing Wave and Photoluminescence Spectroscopy

October 12, 2021
Author(s)
J A. Gupta, Joseph Woicik, S P. Watkins, D A. Harrison, E D. Crozier, B A. Karlin
Using the In-L fluorescence produced by normal-incidence X-ray standing waves, we have measured the layer perfection and positions for ML = 1 and 1/2 (where ML = # of mono layers) InAs quantum wells buried in GaAs(001). Growth temperature effects were

Layered Double Hydroxides as Cation Exchange Materials

October 12, 2021
Author(s)
Paul Braterman, Nandika A. D'Souza, Jeffrey W. Gilman, Mickey C. Richardson, Laxmi K. Sahu, Mauro Zammarano
Layered double hydroxides (LDH) are a class of materials formally related to brucite-like hydroxides by the incorporation of higher valent cations, such as Al(III). The layer charge is neutralized by the insertion of any of a large range of exchangeable

Lead-free Solder Alloys: NEMI Recommendation

October 12, 2021
Author(s)
E -. Bradley, C A. Handwerker, J -. Sohn
There has been substantial discussion worldwide in the electronics assembly community regarding the ideal composition for the primary lead-free alloy for use as a replacement for eutectic Sn-Pb in electronics assembly. Over the last two years, a consensus

Learning to Recognize Distributional Functions

October 12, 2021
Author(s)
J E. Devaney, L Hunter, James J. Filliben
This paper introduces a novel methodology that enables recognition of distributional functions without doing a fit of the data to the distribution. This methodology combines the technique of equation signatures, which uses coefficient independent

Lessons From Ultraviolet Monitoring Spectroradiometer Intercomparisons

October 12, 2021
Author(s)
E A. Thompson, E A. Early
A series of three interagency solar ultraviolet monitoring spectroradiometer intercomparisons were conducted at Table Mountain outside Boulder, Colorado. The primary purpose of these intercomparisons was to compare the solar ultraviolet irradiances

Local Structure and Dynamics Studied by Force Modulation Spectroscopy and Imaging

October 12, 2021
Author(s)
William J. Price, P K. Kuo, T R. Lee, Z C. Ying, Gang-Yu Liu
Using nanoengineered structures of self-assembled monolayers on gold, asystematic investigation was conducted to study the sensitivity of force modulation AFM to molecular level packing, domain boundaries, and chemical functionality. Tip-surface contact

Long-Term Environmental Fatigue of Pultruded Glass-Fiber-Reinforced Composites

October 12, 2021
Author(s)
Kate Liao, Carl R. Schultesiz, Donald L. Hunston
Pultruded glass-fiber-reinforced vinyl ester composite coupons were subjected to four-point-bend fatigue in various environments to study long-term durability for infrastructure applications. Several groups of specimens were aged in water or in water

Low Dielectric Constant Nanocomposite Thin Films Based on Silica Nanoparticle and Organic Thermosets

October 12, 2021
Author(s)
Q Lin, Stephen Cohen, Lynne Gignac, Brian Herbst, David Klaus, Eva Simonyi, Jeffrey Hedrick, John Warlaumont, Hae-Jeong Lee, Wen-Li Wu
Low dielectric constant (low-k) nanocomposite thin films have been prepared by spin coating and thermal cure of solution mixtures of two organic low-k thermoset pre-polymers and a silica nanoparticle with an average diameter of about 8nm. The electrical

Low Temperature Compaction of Nanosize Powders

October 12, 2021
Author(s)
E J. Gonzalez, Gasper J. Piermarini
In recent years there has been a strong interest in the processing of nanosize ceramic powders because of the potential of sintering them at low temperatures and also because ceramic pieces made of nanosize gram structures may exhibit superior mechanical

Low-energy electron collisions with sodium: Scattering of spin-polarized electrons

October 12, 2021
Author(s)
H L. Zhou, B L. Whitten, W K. Trail, M A. Morrison, K B. MacAdam, K Bartschat, D W. Norcross
The electron-sodium system is an excellent prototype of non-relativistic electron scattering from a quasi-one-electron atomic target, and is tractable both experimentally and theoretically. Recently, this system has been studied in a series of

Low-Temperature Kinetics of the Reaction of the OH Radical With Hydrogen Peroxide

October 12, 2021
Author(s)
A B. Vakhtin, D C. McCabe, A R. Ravishankara, S R. Leone
The kinetics of the reaction of the OH radical with hydrogen peroxide. H 2O 2 are studied over a temperature range of 96-296 K. The low-temperature environment is provided by a pulsed Laval nozzle supersonic expansion of nitrogen with admixed H 2O 2
Displaying 3826 - 3850 of 74647