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Richard S. Gates, William A. Osborn, Gordon A. Shaw
Calibration of the flexural spring constant for atomic force microscope colloid probe cantilevers provides significant challenges. The presence of a large attached spherical added mass complicates many of the more common calibration techniques such as
Mark S. Lowenthal, Eric L. Kilpatrick, Karen W. Phinney
Chromatographic separation of monosaccharides hydrolyzed from glycoconjugates or complex, aggregate biomaterials, can be achieved by classic analytical methods without a need for derivatizing the monosaccharide subunits. A simple and sensitive method is
Additive manufacturing (AM) continues to grow as an advanced manufacturing technique. The most recent industry report from Wohlers and Associates indicates AM represented $1.6Bin revenue from parts, systems, and other supporting industries in 2012 [Wohlers
This paper describes the addition of Collision-Induced Absorption (CIA) into the HITRAN compilation. The data from different sources have been cast into a consistent format and formalism. The implementation of these new spectral data into the HITRAN
Vyacheslav B. Podobedov, George P. Eppeldauer, Thomas C. Larason
A new definition is proposed for the calibration of Night Vision Goggle (NVG) gains. This definition is based on the measurement of radiometric input and output quantities of the NVG. While the old definition used the equivalent fL which is a non SI
Joshua A. Gordon, Ryan D. Davis, Sara Lance, Margaret A. Tolbert
The development and characterization of a long working-distance optical trap to analyze a diverse range of particle phase transformations and crystal growth processes is described. Utilizing an upward propagating Gaussian beam and a down-ward propagating
Mobile robots are devices that can move autonomously to accomplish their goals. This paper provides a review of such robots, mainly oriented towards manufacturing applications. It describes the kinds of mobile robots that are used and what criteria are
We present a free-space microwave experimental measurement system for the non-destructive testing of composite materials. The system operates in the Q- frequency band of 30 GHz to 50 GHz with fixed wave propagation distance between free-space antennas
Fan Zhang, Andrew J. Allen, Lyle E. Levine, Derrick C. Mancini, Jan Ilavsky
The needs both for increased experimental throughput and for in-operando characterization of functional materials under increasingly realistic experimental conditions have emerged as major challenges across the whole of crystallography. Aiming to address
The Congruent Matching Cells (CMC) method was invented at the National Institute of Standards and Technology (NIST) for firearm evidence identifications. The CMC method divides the entire image into small correlation cells and uses three sets of four
Keith A. Gillis, James W. Schmidt, Michael R. Moldover, James B. Mehl
With calibrations of large flow meters in mind, we established the feasibility of determining the mass M of argon gas contained within a 0.3 m 3 commercially manufactured pressure vessel ("tank") with a relative standard uncertainty of u r(M) = 0.0016 at 0
Jason P. Campbell, Jason T. Ryan, Pragya R. Shrestha, Zhanglong Liu, Canute I. Vaz, Jihong Kim, Vasileia Georgiou, Kin P. Cheung
Electron spin resonance (ESR) spectroscopys affinity for detecting paramagnetic free radicals, or spins, has been increasingly employed to examine a large variety of biochemical interactions. Such paramagnetic species are broadly found in nature and can
Aaron N. Johnson, Joey T. Boyd, Eric Harman, Mohammad M. Khalil, Jacob E. Ricker, Christopher J. Crowley, Rodney A. Bryant, Iosif I. Shinder
The amount of CO 2 emitted from a coal-fired power plant (CFPP) is measured by continuous emissions monitoring systems (CEMS) permanently installed in the exhaust smokestack. Both the CO 2 concentration and the bulk flow are continuously measured by CEMS
For almost 50 years flow measurement applications using critical flow venturis (CFVs) have relied exclusively on the critical flow function (C*) to correct for viral effects. This work shows that C* does not account for all real gas effects. For high beta
The Fluid Metrology Group (FMG) at NIST is developing a primary, dynamic gravimetric liquid flow standard for use in the range 1 mL/min to 100 nL/min (and eventually lower). An elevated reservoir of water with a pressure head of a few centimeters provides
Iosif I. Shinder, Vladimir Khromchenko, Michael R. Moldover
Outdoor air flows and flue-gas flows in large conduits and large stacks have significant swirl and turbulence. Accurate measurements of such complex flows are needed by weather services and diverse industries (e.g. automotive, aircraft, wind-power, fossil
Jodie G. Pope, Aaron N. Johnson, Bernard J. Filla, Joey T. Boyd, Vern E. Bean, Christopher J. Crowley
We describe a new dynamic, gravimetric, liquid flow standard (LFS) that determines flow by measuring the rate of change of the liquid mass accumulating in a collection tank. The LFS is a fully- automated,15 kg/s system that uses a proportionalintegral
The need for traceable microwave power measurements for use in communications, defense, spectral line investigation, molecular particle signature identification, material property characterization and others is well established. Traceability for power
Darwin R. Reyes-Hernandez, Michael W. Halter, Jeeseong Hwang
The characterization of internal structures in a polymeric device, specifically of a final product, will require a different set of metrology techniques than those traditionally use in the characterization of microelectronic devices. OCT is relatively new
James A. Fedchak, Julia K. Scherschligt, Makfir Sefa, Nick Phandinh
Spinning rotor gauges (SRGs) are widely used as transfer standards in inter-laboratory comparisons and as secondary standards by calibration laboratories. In both of these applications, it is necessary to ship the SRG for calibration, often internationally
Vincent T. Sironneau, Hong Lin, Zachary Reed, Joseph T. Hodges
We present a cavity ring-down spectrometer which was developed for near-infrared measurements of laser absorption by atmospheric greenhouse gases. This system has several important attributes that make it possible to conduct broad spectral surveys and to
Rick L. Paul, Dagistan NMN Sahin, Jeremy C. Cook, Christoph W. Brocker, Richard M. Lindstrom, Donna J. O'Kelly
A new instrument for cold neutron prompt gamma-ray activation analysis (CNPGAA) has been designed and constructed as part of the recent expansion of the cold neutron guide hall at the NIST Center for Neutron Research (NCNR). Located on neutron guide NGD
Darine El Haddad, Frank Seifert, Leon Chao, Yusi A. Cao, Georgio A. Sineriz, Jon R. Pratt, David B. Newell, Stephan Schlamminger
In early 2014, construction of a new watt balance, named NIST-4, has started at the National Institute of Standards and Technology (NIST). In a watt balance, similar to a mass comparator, the gravitational force of an unknown mass is compensated by an
Large-scale 3D shape retrieval has become an important research direction in content-based 3D shape retrieval. To promote this research area, two Shape Retrieval Contest (SHREC) tracks on large scale comprehensive and sketch-based 3D model retrieval have
This article reviews the correct procedures for draining 5-gallon test measures and truck mounted provers, frequently asked questions concerning the test procedures for draining test measures and provers, and provides information on additional training