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Displaying 1526 - 1550 of 2958

Rockwell Hardness - A Method-Dependent Standards Reference Material

July 1, 1999
Author(s)
Samuel Low, R Gettings, Walter S. Liggett Jr, Jun-Feng Song
Rockwell hardness is a method-dependent measurement of the deformation of a material in response to an applied force. It is not a fundamental physical property of a material. There are no alternative measurement systems to directly or independently measure

Mass Metrology at NIST

April 23, 1997
Author(s)
Zeina J. Kubarych
The mission of the mass group of the Automated Production Technology Division at NIST is to maintain the mass unit, disseminate it to U.S. industry, government, and academia, and provide traceability to the International Prototype Kilogram. Efforts are

Quantum Projection Noise: Population Fluctuations in 2-Level Systems

January 1, 1993
Author(s)
Wayne M. Itano, James C. Bergquist, John J. Bollinger, J M. Gilligan, D J. Heinzen, F L. Moore, M G. Raizen, David J. Wineland
Measurements of internal energy states of atomic ions confined in traps can be used to illustrate fundamental properties of quantum systems, because long relaxation times and observation times are available. In the experiments described here, a single ion

Influence of solidification structure on austenite to martensite transformation in additively manufactured hot-work tool steels

August 15, 2021
Author(s)
Chia-Ying Chou, Niklas H. Pettersson, Durga A, Fan Zhang, Christos Oikonomou, Annika Borgenstam, Joakim Odqvist, Greta Lindwall
The microstructure of a hot-work tool steel additively manufactured using laser powder-bed fusion (L-PBF), and its response to post heat treatment, is studied in detail by microstructure characterization and computational thermodynamics and kinetics. The

Effects of Environmental Temperature and Humidity on the Geometry and Strength of Polycarbonate Specimens Prepared by Fused Filament Fabrication

October 3, 2020
Author(s)
Lichen Fang, Yan Yishu, Ojaswi Agarwal, shengyu Yao, Jonathan Seppala, Sung Hoon Kang
It is widely known that the printing quality of fused filament fabrication (FFF) is heavily affected by environmental temperature and humidity, as the case of warping and porosity. However, there is little understanding about the quantitative relations

High Effeciency Fast Scintillators for the Development of Optical Soft X-Ray Arrays for Laboratory Plasma Diagnostics

August 20, 2007
Author(s)
L F. Delgado-Aparicio, R Vero, D Stutman, M Finkenthal, K Tritz, G Suliman, H W. Moos, R Kaita, R Majeski, B Stratton, L Roquemore, D Johnson, Charles Tarrio
Scintillator-based optical soft x-ray (OSXR) arrays may in the near future, replace the conventional diode arrays used for plasma imaging, tomographic reconstruction, magnetohydrodynamics, transport and turbulence studies in magnetically confined fusion

Micropatterning Neuronal Cells on Polyelectrolyte Multilayers

July 7, 2004
Author(s)
Darwin Reyes-Hernandez, Elizabeth M. Perruccio, Patricia Becerra, Laurie E. Locascio, Michael Gaitan
This paper describes an approach to adhere retinal cells on micropatterned polyelectrolyte multilayer (PEM) lines adsorbed on polydimethylsiloxane (PDMS) surfaces, using microfluidic networks. PEMs were patterned on flat oxidized PDMS surfaces by

Finite Element Simulation of Straight Plunge Grinding for Advanced Ceramics

September 1, 2002
Author(s)
Tze J. Chuang, S Jahanmir, Hai C. Tang
The objective of this work is to model the grinding forces and the associated stress and deformation fields generated in a ceramic workpiece during surface plunge grinding. A two-dimensional finite element model is constructed with the grinding parameters

Role of Flaw Statistics in Contact Fracture of Brittle Coatings

October 1, 2001
Author(s)
P Miranda, Antonia Pajares, F Guiberteau, F Cumbrera, Brian R. Lawn
A flaw statistics analysis is here developed to account for systematic differences between experimentally observed and theoretically predicted critical loads for the initiation of contact-induced radial cracks in brittle coatings on compliant substrates

Electrical Control of the Spatial Uniformity of Reactive Species in Plasmas

December 1, 1999
Author(s)
Mark A. Sobolewski, Kristen L. Steffens
We report a new method for controlling the spatial distribution of reactive chemical species in a parallel-plate reactor, by means of a variable-impedance load placed between the unpowered electrode and ground. The technique was demonstrated in 89% CF(sub4

Plastic Flip-Chip-BGA Carrier With Microvias for Chip Scale Packaging

June 2, 1998
Author(s)
Jan Obrzut, M Jimarez
We evaluated a near-chip-scale package, that utilizes the flip-chip, plastic-ball-grid-array technology with microvias. The microvias were photolithographically patterned in built-up dielectric layers. We verified optimal conditions for photo-exposure and

Imperfect Surface Order and Functionalization in Vertical Carbon Nanotube Arrays Probed by Near Edge X-ray Absorption Fine Structure Spectroscoy (NEXAFS)

October 12, 2021
Author(s)
T Hemraj-Benny, S Banerjee, S Sambasivan, Daniel A. Fischer, G Eres, Alexander Puretzky, David B. Geohegan, D H. Lowndes, J A. Misewich, S S. Wong
Probing surface order in nanotube systems is of fundamental importance for incorporation of these materials into practical electronic devices. The current study pertains to analysis of the surface orientation of vertically aligned single-walled and multi

Improved Transition Oscillator Probabilities for Laser Transitions in Xe I

October 12, 2021
Author(s)
Abhijit Dasgupta, J P. Apruzes, O Zatsarinny, K Bartschat, Charlotte F. Fischer
The atomic xenon laser is among the most efficient and powerful of thenear-infrared gas lasers, especially when pumped by molecular ions in an Ar-Xemixture. Accurate oscillator strengths for the laser transitions are criticaltodeveloping a fundamental

Investigating Sub-bandgap Spectral Effects in GaInP-on-Ge Solar Cells

August 26, 2021
Author(s)
Brianna Conrad, Behrang Hamadani
There is a fundamental understanding in photovoltaics that sub-bandgap light will not be absorbed in the solar cell and therefore will not affect the power generation. We have shown a novel phenomenon in which sub-bandgap illumination is required for good
Displaying 1526 - 1550 of 2958
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