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Search Publications

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Displaying 29001 - 29025 of 74178

In-Situ Visualization of Novel Polymer Droplet Morphologies During Extrusion

October 16, 2008
Author(s)
Erik K. Hobbie, Kalman Migler
We report the observation of novel droplet morphologies in the high stress layers near the walls of a specially instrumented slit die. We utilize in-situ optical microscopy to study a dilute blend of polystyrene (PS) in a polyethylene (PE) matrix. At low

InChI a Structure Based IUPAC Identifier for 3-D Structures of AIDS Inhibitors

October 16, 2008
Author(s)
M D. Prasanna, H Rodriguez, J Vondrasek, A Wlodawer, Talapady N. Bhat
The human immunodeficiency virus encodes an aspartic protease which is responsible for posttranslational proteolytic processing of the gag and gag-pol polyprotein gene products into mature functional proteins. Following these proteolytic activities, the

Incorporation of Stereo, Regio and Comonomer Defects Into the Crystalline Regions of Isotactic Polypropylene: Results From NMR, Molecular Dynamics and Chemical Shift Calculations

October 16, 2008
Author(s)
David L. VanderHart, Marc R. Nyden, R G. Alamo, L Mandelkern
We have shown that under conditions of crystallization during cooling at 1C/min, substantial amounts of 'defects' of the types a) stereo-mrrm, b) regio-2,1-erythro, c) ethylene-comonomer and d) butylene- comonomer can be found in the crystalline regions

Index of Retraction and its Temperature Dependence of Calcium Fluoride Near 157nm

October 16, 2008
Author(s)
John H. Burnett, Ulf Griesmann, R Gupta, T E. Jou
We have made accurate measurements near 157 nm of the relative index of refraction, its dispersion, and its temperature dependence for two grades of calcium fluoride in N 2 gas. Accurate measurements of the quantitites are needed for the design of lens

Infrared and Raman Studies of the Verwey Transition in Magnetite

October 16, 2008
Author(s)
L V. Gasparov, D B. Tanner, D B. Romero, H Berger, G Margaritondo, L Forro
We present infrared and Raman measurements of magnetite (Fe 3O 4). This material is known to undergo a metal-insulator and a structural transition (Verwey transition) at T V = 120 K. At temperatures below T V, we observe a strong gap-like suppression of

Infrared Spectrum and Revised Energy Levels for Neutral Krypton

October 16, 2008
Author(s)
Craig J. Sansonetti, Marion Greene
We observed the spectrum of neutral krypton (Kr I) in its naturally occurring isotopic mixture as emitted by a microwave-excited electrodeless discharge lamp with the National Institute of Standards and Technology 2-m Fourier transform spectrometer. The

Inhibition of Silane Ignition by Iodine Containing Additives

October 16, 2008
Author(s)
Valeri I. Babushok, Wing Tsang
The results of numerical studies on the influence of iodine and hydrogen iodide additives on silane self-ignition limits are reported. The entire matrix of possibilities with regard to silane and oxygen ratios was covered. The temperature and pressures

Injectable Calcium Phosphate Cements

October 16, 2008
Author(s)
Laurence C. Chow, Milenko Markovic, Shozo Takagi
Self-hardening calcium phosphate cements (CPC) have been the subject of considerable interest in biomaterials research, especially as a bone graft material. The first published CPCs consisted of tetracalcium phosphate (TTCP) and dicalcium phosphate

Innovation in Telehealth and a Role for the Government

October 16, 2008
Author(s)
R N. Spivack
America's healthcare system is regarded as among the world's best. The application of new technologies to medical care has enabled significant progress. However, the wider adoption of telehealth technologies promises even greater access and higher quality

Instrumentation for Old Gravity

October 16, 2008
Author(s)
J E. Faller
Instrumental capabilities for both relative and absolute gravity measurements have evolved over the past 40 years to the point where today measurements can be made at the parts in 10 9 level of precision. Large but still portable absolute gravimeters have

Interaction Between Putidaredoxin and Its Redox Partner, Putidaredoxin Reductase

October 16, 2008
Author(s)
Marcia J. Holden, M P. Mayhew, V L. Vilker
Using site-directed mutagenesis we altered surface residues on Putidaredoxin to investigate which side-chain residues might be involved in the binding of Putidaredoxin to its redox partner, Putidaredoxin reductase. We focused on the charged residues of

Interaction Effects in Optically Dense Materials

October 16, 2008
Author(s)
Steven T. Cundiff, J M. Shacklette, Virginia O. Lorenz
The properties of optically dense materials are influenced by interactions between elementary optical excitations. Since such interactions are absent in the dilute limit, the resulting properties are unique to optically dense materials. While linear

Intercomparisions of Reflectance Measurements

October 16, 2008
Author(s)
P Y. Barnes, B. Carol Johnson, James J. Butler, C J. Bruegge, S F. Biggar, P R. Spyak, M M. Pavlov, E A. Early
A comparison of spectral diffuse reflectance between different national standards laboratories is being planned under the direction of the Comit* Consultatif de Photom*trie et Radiom*trie (CCPR). A similar comparison of bi-directional reflectance

Interconnect Failure Due to Cyclic Loading

October 16, 2008
Author(s)
R R. Keller, Reiner Monig, Cynthia A. Volkert, E Arzt, R Schwaiger, O Kraft
The damage generated by AC currents at 100 Hz in interconnects has been studied andcompared with mechanical fatigue damage in thin films. The nature of the damage under the twoloading conditions is qualitatively similar, supporting the idea that the AC

Interfacial Free Energies and the Creep of Multilayer Thin Films

October 16, 2008
Author(s)
Daniel Josell, W Carter
Experiments utilizing the creep properties of multilayer thin films to determine underlying free energies are presented with essential theory. A new technique utilizing tubular multilayer foils is then described.
Displaying 29001 - 29025 of 74178