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Journals

Unusual Multilayered Structures in PEO/Laponite Nanocomposite Films

November 19, 2004

Author(s)

Avinash Dundigalla, Sheng Lin-Gibson, F Ferreiro, M M. Malwitz

The unusual structure of poly-ethylene-oxide and Laponite clay in transparentnanocomposite films was investigated using scanning electron, atomic force, optical...

Standards of time and frequency at the outset of the 21st century

November 19, 2004

Author(s)

Scott Diddams, James C. Bergquist, Steven R. Jefferts, Christopher W. Oates

In this paper we review state-of-the-art atomic time and frequency standards and discuss some of their uses in science and technology. After fifty years of...

Metrologic Traceability of Total Thyroxine Measurements in Human Serum: Efforts to Establish a Network of Reference Measurement Laboratories

November 18, 2004

Author(s)

L M. Thienpont, K Van Uytfanghe, J Marriot, P Stokes, L Siekmann, A Kessler, David M. Bunk, Susan S. Tai

Effective Emissivity of a Cylindrical Cavity with an Inclined Bottom: I. Isothermal Cavity

November 16, 2004

Author(s)

Leonard M. Hanssen, A Prokhorov

Collaborative Thermal Conductivity Measurements of Fibrous Glass and Expanded Polystyrene Reference Materials

November 15, 2004

Author(s)

Robert R. Zarr, James J. Filliben

Thermal conductivity measurements of four thermal insulation reference materials are presented. The measurements were obtained from an international...

Transport Coefficients of the Lennard-Jones Model Fluid. II Self-diffusion

November 15, 2004

Author(s)

K Meier, Arno R. Laesecke, Stephan Kabelac

Competing Damage Modes in All-Ceramic Crowns: Fatigue and Lifetime

November 15, 2004

Author(s)

Yu Zhang, Brian R. Lawn

A study is made of fracture from cyclic loading of WC spheres on the surfaces of brittle layers on compliant substrates, as representative of repetitive...

Time-division multiplexing of high-resolution TES X-ray microcalotimeters: Four pixels and beyond

November 15, 2004

Author(s)

W.Bertrand (Randy) Doriese, James A. Beall, Steven Deiker, William Duncan, S. L. Ferreira, Gene C. Hilton, Kent D. Irwin, Carl D. Reintsema, Joel Ullom, Leila R. Vale, Yizi Xu

We present experimental results from a four-pixel array of transition-edge-sensor, x-ray microcalorimeters read out through a single amplifier channel via a...

Boltzmann Test of Slonczewski's Theory of Spin Transfer Torque

November 12, 2004

Author(s)

J Xiao, A Zangwill, Mark D. Stiles

We use a matrix Boltzmann equation formalism to test the accuracy of Slonczewski's theory of spin-transfer torque in thin-film heterostructures where a non...

Effect of Steel and Tungsten Carbide Ball Indenters on Rockwell Hardness Tests

November 11, 2004

Author(s)

Li Ma, Samuel R. Low III, J L. Fink

Rockwell hardness (HR) is a valuable and widely used indentation hardness test for evaluating mechanical properites of metallic materials. For the Rockwell...

External efficiency of Pt/n-GaN Schottky diodes in the spectral range 5-500 nm

November 11, 2004

Author(s)

S Aslam, Robert E. Vest, D Franz, F Yan, Y Zhao, D B. Mott

Letter to the Editor: IONIC LIQUIDS IN ORGANIC SYNTHESIS

November 8, 2004

Author(s)

Joe W. Magee

Letter to the editor.

Lateral Coupling of In_xGa_1-xAs/GaAs quantum dots investigated using differential transmission spectroscopy

November 8, 2004

Author(s)

Kevin L. Silverman, Richard Mirin, Steven T. Cundiff

Coupling between InGaAs/GaAs quantum dots is investigated using differential transmission spectroscopy. Two-color pump-probe techniques are used to spectrally...

Simultaneous Concentration and Separation of Enantiomers with Chiral Temperature Gradient Focusing

November 6, 2004

Author(s)

K M. Balss, Wyatt N. Vreeland, Karen W. Phinney, David J. Ross

Elastic Flow Instability, Curved Streamlines, and Mixing in Microfluidic Flows

November 5, 2004

Author(s)

Jai A. Pathak, David J. Ross, Kalman D. Migler

The optical calcium frequency standards of PTB and NIST

November 5, 2004

Author(s)

U Sterr, C Degenhardt, H Stoehr, Ch. Lisdat, H Schnatz, J Helmcke, F Riehle, G Wilpers, Christopher W. Oates, Leo W. Hollberg

We describe the current status of the optical calcium frequency standard with laser-cooled neutral atoms realized in two different laboratories for the purpose...

An Experimental Investigation of Sootshell Formation in Microgravity Droplet Combustion

November 1, 2004

Author(s)

Samuel L. Manzello, A Yozgatligil, M Y. Choi

Spherically-symmetric droplet combustion experiments were performed in an effort to better understand the mechanism leading to sootshell formation. The...

Scanning Electron Microscopy Imaging of Hydraulic Cement Microstructure

November 1, 2004

Author(s)

Paul E. Stutzman

Microscopy of portland cement clinker and cementitous materials dates to the first petrographic microscope in the late 19th century. The development of the...

Photoassociative Formation of Ultracold Polar KRb Molecules

November 1, 2004

Author(s)

Svetlana A. Kotochigova, Eite Tiesinga, Paul S. Julienne

We investigate the effectiveness of creating polar ground state KRb molecules by two-color photoassociative spectroscopy. In this process the molecules are...

Measurement of Particle Size Distribution in Portland Cement Powder: Analysis of ASTM Round-Robin Studies

November 1, 2004

Author(s)

Chiara F. Ferraris, Vincent A. Hackley, A Aviles

A distribution of particle sizes or particle size distribution (PSD) is a fundamental characteristic of cement powder. Accurate PSDs are required in...