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Due to the rapidly growing interest in energy harvesting from indoor ambient lighting for the powering of internet-of-things devices, accurate methods for proper measurements of the current vs voltage characteristics of light-harvesting solar photovoltaic
Shendong Shi, Balasubramanian Muralikrishnan, Vincent Lee, Daniel S. Sawyer, Octavio Icasio-Hern?ndez
Periodic performance evaluation is a critical issue for ensuring the reliability of data from terrestrial laser scanners (TLSs). With the recent introduction of the ASTM E3125-17 standard, there now exist standardized test procedures for this purpose
The measurement of heat transfer coefficients in microchannels is complicated due to the small sizes involved. Moreover, a heat transfer mechanism which is not usually considered, the axial conduction effect in the channel wall, must also be evaluated in
Frederic Overney, Nathan Flowers-Jacobs, Blaise Jeanneret, Alain Rufenacht, Anna Fox, Paul Dresselhaus, Samuel Benz
This paper presents a full characterization of a Dual Josephson Impedance Bridge (DJIB) at frequencies up to 80kHz by using the DJIB to compare the best available impedance standards that are (a) directly traceable to the quantum Hall effect, (b) used as
2019 was a big year for Metrology. The international system of units was revised on World Metrology Day, May 20th, that year [1]. What will 2020 bring? In this article we discuss five promising advances that we have on a watchlist for 2020. First, we
Alan L. Migdall, Evan Meyer-Scott, Christine Silberhorn
We review the rapid recent progress in single-photon sources based on multiplexing multiple probabilistic photon-creation events. Such multiplexing allows higher single-photon probabilities and lower contamination from higher-order photon states. We study
A new method is described to provide a primary calibration of shock measurements produced by a shock measurement system consisting of pendulum excitation and laser Doppler velocimetry. The method uses the laser Doppler velocimeter to determine the total
Walk-through metal detectors (WTMDs) are the mainstay for screening people for the presence of metal threat and/or contraband objects at security checkpoints. Although nonmetallic threats are a concern, most threats encountered in practice are metal or
Measurement uncertainty is a parameter that is used to characterize the dispersion of the values attributed to a measurand. There are multiple definitions of measurement uncertainty that were adopted by various international working groups. The differences
Ann C. Chiaramonti Debay, Luis Miaja Avila, Benjamin W. Caplins, Paul T. Blanchard, Norman A. Sanford, Brian Gorman, David R. Diercks
This paper reports construction of an extreme ultraviolet (EUV) radiation-triggered atom probe tomograph and describes the results from initial experiments on amorphous SiO2. Femtosecond-pulsed coherent EUV radiation of 29.6 nm wavelength (41.85 eV photon
International Organization for Standardization (ISO)/International Electrotechnical Commission (IEC) 80000, the International System of Quantities, collects and organizes the most important physical quantities into a coherent system. In a similar fashion
This publication is a colorful poster illustrating the relationships of the International System of Units (SI) derived units with special names and symbols and the seven traditional base units. The diagram is aligned with the BIPM SI Brochure, 9th edition
Q Liu, M Febbraro, R.J. deBoer, S. Aguilar, A Boeltzig, Y Chen, M Couder, J Gorres, Jamie Weaver, K. T. Macon, M. Wiescher, K. Manukyan, L. Morales, S Pain, W. A. Peters, C. Seymour, G. Seymour, R. Toomey, B. Vande Kolk
Nucleosynthesis in the fi rst generation of massive stars offer a unique setting to explore the creation of the fi rst heavier nuclei in an environment free of impurities from earlier stellar generations. In later generations of massive stars, hydrogen
Nathan E. Flowers-Jacobs, Alain Rufenacht, Anna E. Fox, Steven B. Waltman, Robert E. Schwall, Justus A. Brevik, Paul D. Dresselhaus, Samuel P. Benz
We have recently created a 4 V rms cryocooled JAWS (Josephson Arbitrary Waveform Synthesizer) using 204,960 nearly identical Josephson junctions (JJs) that are embedded in coplanar-wave guides. The JJs are pulse-biased at repetition rates up to 16 × 10 9
Corey A. Stambaugh, Hamza Shakeel, Maritoni A. Litorja, Joshua M. Pomeroy
The quartz crystal microbalance has been deployed across industry and academy for the monitoring of the film thickness during depositions. Over a half-a-century of academic and industrial research has gone into understanding the relation between film
The orthogonal superposition (OSP) technique is advantageous for measuring structural dynamics in complex fluids subjected to a primary shear flow. This technique superimposes a small amplitude oscillation orthogonal to a primary shear flow to measure the
Varun Verma, Jascha A. Lau, Arnab Choudhury, Li Chen, Dirk Schwarzer, Alec M. Wodtke
Molecules are quantum objects; therefore, isomerization fundamentally involves quantum states bound within a molecular potential energy function with multiple minima. For isolated gas-phase molecules, eigenstates well above the isomerization saddle points
Constantinos Makrides, Daniel Barker, James A. Fedchak, Julia Scherschligt, Stephen Eckel, Eite Tiesinga
We have computed the thermally-averaged total, elastic rate coefficient for the collision of a room-temperature helium atom with an ultra-cold lithium atom. This rate coefficient has been computed as part of the characterization of a cold atom vacuum
Kaleb J. Duelge, Jeremie Parot, Vincent A. Hackley, Michael R. Zachariah
Protein aggregation is a significant concern in bioprocessing and end use applications. Here the thermal aggregation kinetics of bovine serum albumin (BSA) and α-chymotrypsinogen A (α- chymo) were measured over a range of concentrations and temperatures by
Thomas Gerrits, Alan L. Migdall, Joshua C. Bienfang, John H. Lehman, Sae Woo Nam, Jolene D. Splett, Igor Vayshenker, Chih-Ming Wang
We measure the detection efficiency of single-photon detectors at wavelengths near 851 nm and 1533.6 nm. We investigate the spatial uniformity of one free-space-coupled single-photon avalanche diode and present a comparison between fusion-spliced and
We report here on the design, fabrication and calibration of nanocalorimeter sensors used in the NIST Nanocalorimetry Measurements Project. These small scale thermal analysis instruments are produced using silicon microfabrication approaches. A single
Ronald S. Lankone, David G. Goodwin, Li Piin Sung, Emmanuel Ruggiero, Klaus Vilsmeier, Philipp Mueller, Sorin Pulbere, Katie Challis, Yuqiang Bi, Paul Westerhoff, James Ranville, David H. Fairbrother, Wendel Wohlleben
Pigments with nanoscale dimensions are added to exterior coatings to achieve desirable color and gloss properties. The present study compared the performance, degradation, and release behavior of an acrylic coating that was pigmented by a nanoform of Cu
This handbook compiles the latest Uniform Laws and Regulations and related interpretations and guidelines adopted by the National Conference on Weights and Measures, Inc. (NCWM). At the 1983 Annual Meeting, the NCWM voted to change the title of Handbook
Breyanna M. Blackwell, David Sefcik, Lisa Warfield
This handbook has been prepared as a procedural guide for the compliance testing of net content statements on packaged goods. Compliance testing of packaged goods is the determination of the conformance of the- results of the packaging, distribution, and
Martina Marzano, Mattias Kruskopf, Alireza Panna, Albert Rigosi, Dinesh K. Patel, Hanbyul Jin, Stefan Cular, Luca Callegaro, Randolph Elmquist, Massimo Ortolano