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Progress in nanotechnology is enabled by and dependent on the availability of measurement methods with spatial resolution commensurate with nanomaterials length scales. Chemical imaging techniques, such as scattering scanning near-field optical microscopy
D Ott, Hao H. Zhang, Daniel B. Ott, Xuezeng Zhao, Jun-Feng Song
The spline filter is a standard linear profile filter recommended by ISO/TS 16610-22 (2006). The primary advantage of the spline filter is that no end-effects occur as a result of the filter. The ISO standard also provides the tension parameter β=0.62524
Michael H. Francis, Ronald C. Wittmann, David R. Novotny, Joshua A. Gordon
We describe millimeter-wave near-field measurements made with the new National Institute of Standards and Technology (NIST) robotic scanning system. This system is designed for high-frequency performance, is capable of scanning in multiple configurations
There are several different ways that measuring systems (which include measuring instruments) can be characterized, including calibration, adjustment, and verification (or testing). Common elements of such characterizations include comparisons of indicated
In this editorial, we will provide a brief synopsis of the proceedings of the 2015 Workshop on the Determination of the Fundamental Constants, a broad overview of the fundamental constants themselves, and finally a short history of compilations and
Presentation at the BIPM on (1) Issues with the uncertainty evaluation associated with the calibration of indicating instruments; and (2) the growing problem with outlier rejection in measurements with measurands defined by extreme values
Eric Davis, Nichole Nadermann, Kirt A. Page, Christopher Stafford, Edwin Chan
Heterogeneous, nanophase segregated polymers are ubiquitous in technologies such as fuel cells and batteries, water purification, and drug delivery, where the thickness of the polymer layer ranges from hundreds of microns to tens of nanometers
Felipe Guzman, Yiliang Bao, Jason J. Gorman, John R. Lawall, Jacob M. Taylor, Thomas W. LeBrun
Current acceleration primary standards reach relative uncertainties of the order of 0.001 and consist of complex test facilities, typically operated at National Metrology Institutes. Our research focuses on the development of silicon mechanical oscillator
Felipe Guzman, Oliver Gerberding, John T. Melcher, Julian Stirling, Jon R. Pratt, Gordon A. Shaw, Jacob M. Taylor
Compact optical cavities can be combined with motion sensors to yield unprecedented resolution and SI-traceability in areas such as acceleration sensing and atomic force microscopy AFM, among others. We have incorporated Fabry-Perot fiber-optic micro
Galen H. Koepke, William F. Young, John M. Ladbury, Jason B. Coder
We examine interference and coexistence testing issues, test methods, and the need to update and develop new test methodologies related to the use of wireless devices in critical infrastructure systems. A case study on interference is presented along with
Conformance testing is the method that is used to determine if a product, process or system (known as an implementation under test) satisfies the requirements specified in the base standard. The goal of conformance testing is to capture enough of the
Solomon I. Woods, James E. Proctor, Alan W. Smith, Timothy M. Jung
We have developed a cryogenic amplifier for the measurement of small current signals from cryogenic optical detectors. Typically operated with gain near 10^7, the amplifier performs well from DC to greater than 30 kHz, and exhibits noise level near the
Piezoelectric actuation of atomic force microscope (AFM) cantilevers often suffers from spurious mechanical resonances in the loop between the signal driving the cantilever and the actual tip motion. These spurious resonances can reduce the accuracy of AFM
John S. Villarrubia, Andras Vladar, Bin Ming, Regis J. Kline, Daniel F. Sunday, Jasmeet Chawla, Scott List
The width and shape of 10 nm to 12 nm wide lithographically patterned SiO2 lines were measured in the scanning electron microscope by fitting the measured intensity vs. position to a physics-based model in which the lines widths and shapes are parameters
Uncertainty has proven difficult to implement in calibrations labs. The subject has mathematics and statistics that are part of normal scientific research but are seldom found among working metrologists in small calibration labs. There is, however, a
Article announcing the requirements for labeling meats and poultry items resulting from a U.S. Department of Agriculture, Food and Safety Inspection Services release of a ruling effective January 1, 2016. This ruling amends the regulations for descriptive
An easy to implement method for accurately utilizing pyranometer incidence angle dependent calibration factors, or responsivities (uV/W/m2), along with the associated uncertainties has been developed. This method uses algorithms for creating single
The clamped single-edge notched tension (SE(T)) specimen has seen increased use as a single-specimen testing scheme to determine tearing resistance curves in high strength steel pipe. The SE(T) specimen with appropriate notch geometry is a low-constraint
Collé, et al [(2007) Appl. Radiat Isot. 65, 728; (2014) J. Phys. G: Nucl. Part. Phys. 41, 105103], over the course of nearly a decade and with decay data from a period of 20.7 years, initially uncovered and then substantiated a 25 % error in the 209Po half
Richard J. Norcross, Roger V. Bostelman, Joseph A. Falco
The National Institute of Standards and Technology (NIST) is developing test methods for contact bumpers used on Automated Guided Vehicles (AGVs) as basis for safety standards. This paper describes proposed test methods, force measurements for contact
Bradley N. Damazo, Andras Vladar, Olivier M. Marie-Rose, John A. Kramar
The National Institute of Standards and Technology (NIST) is developing a specialized, metrology scanning electron microscope (SEM), having a metrology sample stage measured by a 38 picometer resolution, high-bandwidth laser interferometer system. The
The International System of Units (SI) is supposed to be coherent. That is, when a combination of units is replaced by an equivalent unit, there is no additional numerical factor. Here we consider dimensionless units as defined in the SI, e.g. angular
A resolution metric intended for the resolution analysis of arbitrary spatially calibrated images is presented in this paper. By fitting a simple sigmoidal function to the pixel intensities across slices of the image taken perpendicular to light-dark edges
Analytical ultracentrifugation (AUC) is a first principles based method to determine absolute sedimentation coefficients and buoyant molar masses of macromolecules and their complexes, reporting on their size and shape in free solution. The purpose of this