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Behrang H. Hamadani, Andrew M. Shore, John F. Roller, Howard W. Yoon, Mark Campanelli
We present a light emitting diode (LED)-based system utilizing a combinatorial flux addition method to investigate the nonlinear relationship in solar cells between the output current of the cell and the incident irradiance level. The magnitude of the
We have developed a custom apparatus for the consecutive measurement of the electrical resistivity, the Seebeck coefficient, and the thermal conductivity of materials between 300 K and 12 K. These three transport properties provide for a basic
Guangjun Cheng, Christina A. Hacker, Curt A. Richter, Angela R. Hight Walker
We present an investigation on the etching of graphite catalyzed by the particles produced by dewetting Fe thin films on graphite in forming gas. Raman mapping of the etched graphite shows the thickness variation in the etched channels and reveals that the
Joseph A. Falco, Jeremy A. Marvel, Richard J. Norcross, Karl Van Wyk
Metrics and test methods are needed to characterize the control capabilities of robots with both intrinsic and extrinsic force sensing. The availability of these benchmarks will motivate research product development, and provide a mechanism for reporting
A cavity ring-down spectrometer and condensation particle counter were used to investigate the limitations in the separation of singly and multiply charged aerosol particles by a tandem differential mobility analyzer (DMA) and aerosol particle mass
Michael R. Moldover, Weston L. Tew, Howard W. Yoon
The last 25 years have seen tremendous progress in thermometry in the moderate temperature range (1 K to 1235 K). Various primary thermometers based on different physics have uncovered errors in the International Temperature Scale of 1990 and set the
Compressed-liquid densities of three compositions of the binary mixture dimethyl ether (CAS No. 115-10-6) + pentane (CAS No. 109-66-0) have been measured with a vibrating U-tube densimeter. Measurements were made at temperatures from 270 K to 390 K with
Kathryn E. Keenan, Sheye O. Aliu, Lisa J. Wilmes, David C. Newitt, Ella F. Jones, Wen Li, Michael A. Boss, Nola M. Hylton
Purpose: We present a breast phantom designed to enable quantitative assessment of measurements of T 1 relaxation time, apparent diffusion coefficient (ADC), and other attributes of breast tissue, with long-term support from a national metrology institute
Roger V. Bostelman, Joseph A. Falco, Milli Shah, Tsai H. Hong
Multi-camera motion capture systems are commercially available and are typically used in the entertainment industry to track human motions for video gaming and movies. These systems are proving useful as ground truth measurement systems to assess the
Ndubuisi G. Orji, Hiroshi Itoh, Chumei Wang, Ronald G. Dixson, Sebastian Schmidt, Bernd Irmer, Peter S. Walecki
In atomic force microscopy (AFM) metrology, the tip is a key source of uncertainty. Images taken with an AFM show a change in feature width and shape that depends on tip geometry. This geometric distortion is more pronounced when measuring features with
Deogratias Kibira, Katherine C. Morris, Senthilkumaran Kumaraguru
The emerging concept of smart manufacturing systems is defined in part by the introduction of new technologies that are promoting rapid and widespread information flow within the manufacturing system and surrounding its control. These systems can deliver
Yvonne B. Gerbig, Chris A. Michaels, Robert F. Cook, Jodie E. Bradby
Indentation-induced plastic deformation of amorphous silicon (a-Si) thin films was studied by in situ Raman imaging of the deformed contact region of an indented sample, employing a Raman spectroscopy-enhanced instrumented indentation technique (IIT). The
The NIST Office of Weights and Measures (OWM) over time have received a number of inquiries regarding the suitability, use, and testing of hopper-type scales. The nature of those inquiries provides some indication that there is a lack of detailed
Rainer Feistel, Robert Wielgosz, Stephanie A. Bell, M F. Camoes, J R. Cooper, P Dexter, A G. Dickson, P Fisicaro, Allan H. Harvey, M Heinonen, Olaf Hellmuth, H J. Kretzschmar, J W. Lovell-Smith, Trevor J. McDougall, R Pawlowicz, S Seitz, Petra Spitzer, D Stoica, H Wolf, P Ridout
Water in its three ambient phases plays the dominant thermodynamic role for the functioning principles of the terrestrial climate system. Together with clouds, water vapour in the atmosphere is the strongest greenhouse gas (followed by clouds and carbon
Grady S. White, Adrian Verwolf, Chris M. Poling, Nicholas Barbosa, Nikki S. Rentz
Silicon wafers with micro-machined holes were evaluated for use as low permeation standard artifacts. Accuracy, stability, and reliability were assessed. Two experimental techniques were used: chilled mirror hygrometer and mass loss. The wafers exhibited a
Wei Li, Nhan Van Nguyen, Guangjun Cheng, Angela R. Hight Walker, David J. Gundlach, Yiran Liang, boyuan Tian, Xuelei Liang, Lian-Mao Peng
The broadband (0.7 eV to 9.0 eV) optical properties of chemical-vapor-deposition (CVD) grown graphene are determined by spectroscopic ellipsometry. The optical absorption follows the fine structure constant in the energy range from 1.0 eV to 2.0 eV, but
In this work, scanning near-field microwave imaging was implemented to test the feasibility of the approach for in situ studies of nanosclale objects immersed in liquids under thin dielectric membranes. It was found that mechanical strength and stability
Yilin Yu, Yifei Yu, Yongqing Cui, Wei Li, Gurarslan Alper, Peelaers Hartwin, Aspnes David, Chris Van de Walle, Nhan Van Nguyen, Zhang Yong-Wei, Linyou Cao
The control of photons by field effects, like the gating of electrons, can revolutionize a wide range of fields by enabling active photonic devices whose functions could be manipulated with sophistication and speeds comparable to what achieved in modern
Nathan D. Orloff, Christian J. Long, Jan Obrzut, Laurent Millaud, Francesca Mirri, Thomas R. Kole, Robert D. McMichael, Mattei Pasquali, Stephan J. Stranick, James A. Liddle
Advances in roll-to-roll processing of graphene [1] and carbon nanotube [2] have at last led to the continuous production of high-quality coatings and filaments, ushering in a wave of applications for flexible [3], [4] and wearable [5] electronics, woven
For years (decades, in fact) a definition for datum planes has been sought by ASME and ISO standards writers that combines the contacting nature of traditional surface plate mating with a means of balancing rocking conditions when there is a centrally
Assane Gueye, Peter Mell, Desire Banse, Faical Y. Congo
This study measures and documents growth of Internet connectivity in Africa from 2010 to 2014 with a focus on inter-country relationships. We evaluate both intra-continent connectivity as well as connectivity to other continents. An initial analysis
Sao F. Cheung, Kyle Anderson, Kenia Benitez, Mark J. Soloski, John N. Aucott, Karen W. Phinney, Illarion Turko
The low abundance of bacterial proteins in human serum upon infection imposes a challenge for the early proteomic detection of bacterial infection. To address this challenge, we propose to take advantage of detecting membrane proteins released from