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The National Institute of Standards and Technology coordinates the Micronutrients Measurement Quality Assurance Program (MMQAP) for laboratories that measure fat- and water-soluble vitamins and carotenoids in human serum and plasma. This report describes
Jeanice M. Brown Thomas, David L. Duewer, Margaret C. Kline, Willie E. May, Sam A. Margolis, Neal E. Craft, Katherine E. Sharpless
The National Institute of Standards and Technology coordinates the Micronutrients Measurement Quality Assurance Program (MMQAP) for laboratories that measure fat- and water-soluble vitamins and carotenoids in human serum and plasma. This report describes
Jeanice M. Brown Thomas, David L. Duewer, Margaret C. Kline, Katherine E. Sharpless, Willie E. May, Sam A. Margolis, Neal E. Craft
The National Institute of Standards and Technology coordinates the Micronutrients Measurement Quality Assurance Program (MMQAP) for laboratories that measure fat- and water-soluble vitamins and carotenoids in human serum and plasma. This report describes
James P. Cline, Marcus H. Mendenhall, David R. Black, Donald A. Windover, Albert Henins
The laboratory X-ray powder diffractometer is one of the primary analytical tools in materials science. It is applicable to nearly any crystalline material, and with advanced data analysis methods, it can provide a wealth of information concerning sample
Marcus H. Mendenhall, Donald A. Windover, Albert Henins, James P. Cline
We present a simple way to collect data from an optical position or angle encoder with a readout which interpolates values between the optical features, and to process this data set so as to determine the short-range errors which arise from an
The distance over which the resolution of a microscope image changes appreciably, related to the depth of field, is an important parameter. This value determines the height of an object that can be imaged and said to be in focus. Although this distance
Shonali Nazare, John R. Shields, Szabolcs Matko, Rick D. Davis
Fire behavior of five barrier fabrics has been evaluated both, as an individual component and as a part of composite samples, using different test methods. The quantitative component test methods selected to characterize fire behavior of barrier fabrics
Katherine E. Sharpless, David L. Duewer, Katrice A. Lippa, Andrew L. Rukhin
Although "nutraceuticals" and "functional foods" seem to be ill-defined terms, both are often used to indicate a food that contains compounds providing benefits beyond basic nutrition, often with the expectation that these compounds are protective against
David R. Black, Donald A. Windover, Marcus H. Mendenhall, Albert Henins, James J. Filliben, James P. Cline
The National Institute of Standards and Technology (NIST) certifies a suite of Standard Reference Materials (SRMs) to address specific aspects of the performance of X-ray powder diffraction instruments. This report describes SRM 1976b, the third generation
The National Institute of Standards and Technology (NIST) developed a prototype field test standard (FTS) that incorporates three test methods that could be used by state weights and measures inspectors to periodically test retail hydrogen gas dispensers
Oliver Gerberding, Felipe Guzman, John T. Melcher, Jon R. Pratt, Jacob Taylor
We present an opto-mechanical accelerometer device with high dynamic range, high bandwidth and readout noise levels exceeding 10 μg/√Hz . The straightforward assembly and small cost of our device make it a prime candidate to perform on-site calibrations
Aric W. Sanders, Jaevyn Faulk, Devin T. Edwards, Thomas T. Perkins
In addition to providing the ability to image on the nanoscale, atomic force microscopy (AFM) has the ability to measure small (pN) forces at a single point. This ability has led to new insights into conformation changes in biological molecules; in
Hsin Wang, Shengqiang Bai, Lidong Chen, Alexander Cuenat, Giri Joshi, Holger Kleinke, Jan K?nig, Hee Woong Lee, Joshua Martin, Min-Wook Oh, Wallace Porter, Zhifeng Ren, James Salvador, Jeff Sharp, Patrick Taylor, Alan J. Thompson, Y. C. Tseng
International transport property measurement round-robins have been conducted by the Thermoelectric Annex under the International Energy Agency (IEA) Implementing Agreement on Advanced Materials for Transportation (AMT). The previous round-robins used
Jay H. Hendricks, Jacob E. Ricker, Jack A. Stone Jr., Patrick F. Egan, Gregory E. Scace, Gregory F. Strouse, Douglas A. Olson, Donavon Gerty
The future of pressure and vacuum measurement will rely on lasers and Fabry-Perot optical cavities, and will be based on fundamental physics of light interacting with a gas. Light interacts at the quantum level with matter such that light travels at a
Corey A. Stambaugh, Edward C. Mulhern, Eric C. Benck, Zeina J. Kubarych, Patrick J. Abbott
The redefined kilogram will be realized in vacuum and a method will be required to disseminate the standard to air. NIST has been developing a magnetic suspension system for this purpose. This paper discusses the progress to characterize and improve the
Michal J. Chojnacky, Luis Chaves Santacruz, W Wyatt Miller, Gregory F. Strouse
Accidental freezing of refrigerated vaccine represents a significant public and private healthcare cost. Freeze-damaged vaccines lose their effectiveness, putting communities at risk. U.S. immunization programs have strengthened vaccine storage and
Mihaela L. Vlasea, Brandon M. Lane, Felipe F. Lopez, Sergey Mekhontsev, M A. Donmez
Laser powder bed fusion (PBF) is emerging as the most popular additive manufacturing (AM) method for producing metallic components based on the flexibility in accommodating for a wide range of materials with resulting mechanical properties similar to bulk
Although the scaling theory of polymer solutions has had many successes, this type of argument is deficient when applied to hydrodynamic solution properties. Since the foundation of polymer science, it has been appreciated that measurements of polymer size
XiaoJuan Feng, Hong Lin, Keith A. Gillis, Michael R. Moldover, Jintao Zhang
We report progress in determining the Boltzmann constant k B using a virtual acoustic resonator derived by combining the measured frequencies of the longitudinal acoustic modes of two argon-filled, cylindrical, cavity resonators in such a way as to
As the number of users of additive manufacturing (AM) steadily increases, and considering their demand for material and process specifications, the need for standard protocols for round robin studies is increasing accordingly. Researchers at the National
When transporting CO2 for sequestration, it is important to know the water dew point in order to avoid condensation that can lead to corrosion. We have constructed a flow apparatus to measure the water content at saturation in a compressed gas. A saturator
Recognized sources of error in digital forensics include systematic errors arising from implementation errors, and random errors resulting from faulty equipment. But as digital forensic techniques expand to include statistical machine learning, another
Ronald Colle, Ryan P. Fitzgerald, Lizbeth Laureano-Perez
Ultra-pure, carrier-free 209Po solution standards have been prepared and standardized for their massic alpha-particle emission rate. The standards, which will be disseminated by the National Institute of Standards and Technology (NIST) as Standard
Prem K. Rachakonda, Balasubramanian Muralikrishnan, Katharine M. Shilling, Daniel S. Sawyer, Geraldine S. Cheok, Kamel S. Saidi
Laser scanners have become indispensable tools for fast and accurate 3D image acquisition applications such as part inspection, reverse engineering, cultural heritage digitization, surveying, automotive robotic navigation etc. The Dimensional Metrology