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Thomas J. Bruno, Arron Wolk, Alexander Naydich, Marcia L. Huber
We have recently introduced several important improvements in the measurement of distillation curves of complex fluids. The modifications to the classical measurement provide for (1) a composition explicit data channel for each distillate fraction (for
JP-7 is a hydrocarbon-based kerosene fraction with a low volatility and high thermal stability. JP-7 was developed in the 1950s to meet the more stringent requirements necessary for the development of high-altitude reconnaissance planes that fly at speeds
While the use of ethanol and ethanol blends as motor fuels dates back to the earliest vehicles, ethanol has recently received extraordinary attention as a renewable liquid fuel. In the United States, the application of this fluid is mainly as an additive
Lorna T. Sniegoski, Jocelyn L. Prendergast, Michael J. Welch, Alim A. Fatah, M Gackstetter, R. Q. Thompson
Several point-of-collection (POC) devices for detection of drugs of abuse in oral fluid were studied. The ability of the devices to meet the manufacturers' claims and their practical application to detection of drugs of abuse at low concentrations in oral
----- FOR POLICY REVIEW ONLY ----- The thermal decomposition of RP-1, RP-2, and mixtures of RP-2 with three different additives has been investigated. The mixtures with RP-2 contained 5% 1,2,3,4-tetrahydronaphthalene (tetralin), 5% 1,2,3,4
We used a cross capacitor to measure the relative dielectric permittivity ε r of O 2 at 273 K, 293 K, and 323 K and at pressures up to 6.5 MPa. Simultaneously we measured oxygen's complex refractive index n using a quasi-spherical cavity resonator at
This document describes NIST's high pressure natural gas flow calibration service (NGFCS). Flow calibrations are conducted offsite at the Colorado Experimental Engineering Station Incorporated (CEESI) in Garner, Iowa. A parallel array of nine turbine meter
Robert F. Berg, Michael R. Moldover, M Yao, G A. Zimmerli
We measured shear thinning, a viscosity decrease ordinarily associated with complex liquids, near the critical point of xenon. The data span the range of reduced shear rates: 0.001 < γτ < 700, where γτ is the shear rate scaled by the relaxation time τ of
We determined the zero-density viscosity eta of hydrogen, methane and argon in the temperature range 200 K to 400 K, with standard uncertainties of 0.084 % for hydrogen and argon and 0.096 % for methane. These uncertainties are dominated by the uncertainty
James W. Schmidt, R Gavioso, E May, Michael R. Moldover
Using a quasi-spherical, microwave cavity resonator, we measured the refractive index of helium to deduce its molar polarizability A ε in the limit of zero density. We obtained (A ε,meas - A ε,theory)/A ε = (-1.8plus or minus} 8.4)× 10 -6, where the
Helium leak testing is a vital step in assuring product reliability for anything that must be packaged in a sealed container. Examples abound from blister packaging for pharmaceuticals to aluminum wheel rims for automobiles. In order to quantify detected
We have recently introduced several important improvements in the measurement of distillation curves distillation curves for complex fluids. The modifications to the classical measurement provide for (1) temperature and volume measurements of low
In previous work, several significant improvements in the measurement of distillation curves for complex fluids were introduced. The modifications to the classical measurement provide for (1) temperature and volume measurements of low uncertainty, (2)
Keith A. Gillis, Iosif I. Shinder, Michael R. Moldover
We measured the resonance spectrum of an acoustic resonator filled with xenon near its critical temperature Tc. We reduced the effect of gravity on the xenon by convective stirring to achieve a temperature resolution of (T-Tc)/Tc 7 10-6. The data yield
This document describes the Water Flow Calibration Facility (WFCF) at the National Institute of Standards and Technology (NIST). This facility has three parallel pipelines with diameters of 100, 200 and 400 mm and three weighing systems with capacities of
The distillation (or boiling) curve of a complex fluid is a critically important indicator of the bulk behavior or response of the fluid. For this reason, the distillation curve, usually presented graphically as boiling temperature against volume fraction
In a previous paper, a number of improvements in the method and apparatus used for the measurement of distillation curves for complex hydrocarbon fluid mixtures were presented. These improvements included the addition of a composition-explicit channel of
A correlation for the viscosity of pentafluorethane (R125) has been developed based on a compilation and critical assessment of the available experimental data. The correlation covers a wide range of fluid states, including the supercritical region. It is
Aaron N. Johnson, C L. Merkle, Michael R. Moldover, John D. Wright
We computed the flow of four gases (He, N 2, CO 2, and SF 6) through a critical nozzle by augmenting traditional computational fluid dynamics (CFD) with a rate equation that accounts for τ relax, a species-dependent relaxation time that characterizes the
John D. Wright, Aaron N. Johnson, Michael R. Moldover, Gina M. Kline
This document provides a description of the 34 L and 677 L pressure, volume, temperature, and time (PVTt) primary gas flow standards operated by the National Institute of Standards and Technology (NIST) Fluid Flow Group. These facilities are used to
Two techniques are described for the measurement of fluid temperatures in microfluidic systems based on temperature-dependent fluorescence. In the first technique, a single, strongly temperature-dependent fluorophore, rhodamine B, is used as the basis for
The focus of this effort is to investigate the dispersal of liquid fire suppression agents around solid obstacles, and obtain a better understanding of the physical processes of droplet transport in cluttered spaces. An experimental investigation is
In this chapter, we review the principles of sound propagation in fluid systems. From a study of the hydrodynamic equations, sound propagation is shown to be a wave phenomenon. The speed of sound then can be derieved at any state point from a knowledge of
Keith A. Gillis, John J. Hurly, Michael R. Moldover
Acoustic resonators have been developed at NIST as tools to measure the thermodynamic and transport properties of gases. High Q cylindrical acoustic resonators are routinely used to measure the speed of sound in gases with uncertainties of 0.01% or less