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Since its initial recognition in 1928 and commercialization in 1936, R-22 has been applied in systems ranging from the smallest window air conditioners to the largest chillers and heat pumps, including those for district cooling and heating. Individual
The uncertainties of the mean diameters of the 1.0 micrometer SRM 1690 polystyrene spheres and of the 0.3 micrometer SRM 1691 polystyrene spheres are recomputed using the current NIST Guidelines for computing uncertainty. The revised expanded uncertainty
Jae H. Kim, George W. Mulholland, S R. Kukuck, D Y. Pui
The slip correction factor has been investigated at reduced pressures and high Knudsen number using polystyrene latex (PSL) particles. Nano-differential mobility analyzers (NDMA) were used in determining the slip correction factor by measuring the
Richard D. Peacock, Jason D. Averill, Richard W. Bukowski, Paul A. Reneke
This report documents the first test series in the program conducted to characterize the test environment. Data presented include CO, CO2, O2, smoke obscuration, and temperature. Additional measurement of smoke particle size and concentration, additional
J F. Widmann, J X. Duchez, Joseph M. Conny, George W. Mulholland
This note describes mesurements of the optical extinction coefficient of carbonaceous aerosol produced during hydrocarbon combustion. Measurements of the mass specific extinction coefficient were obtained by laser extinction at 632 nm wavelength. The
A methodology is presented for the mixture proportioning of ordinary Portland cement concretes to supply internal curing via the addition of saturated lightweight fine aggregates. The necessary internal curing water is calculated to balance the water
Shi et al. have applied an equation for solution equivalent conductivities (denoted by A) to the problem of estimating species equivalent conductivities (denoted by A.), with potentially pathological consequences, as I will show. For completeness, I will
A key finding of past research on natural ventilation is that the potential application of pure natural ventilation systems may be limited in the United States by issues such as climate suitability, humidity control, and reliability. However, hybrid (or
This paper investigates the effect that the bulk lubricant concentration has on the non-adiabatic lubricant excess surface density on a roughened, horizontal flat pool-boiling surface. Both pool boiling heat transfer data and lubricant excess surface
A new hybrid in-situ sealant-testing device that uses movement to both characterize and fatigue standard ASTM C719 sealant samples is described. This five sample device, records the force-response data for every deformation cycle of every sample. From this
Walter W. Jones, William D. Davis, D D. Evans, David G. Holmberg, Steven T. Bushby, K A. Reed
On May 3, 2004, NIST sponsored a workshop to identify the information needs for emergency responders. The purpose of this workshop was to obtain guidance on the type of building static and dynamic tactical information needed by public safety officials, how
Results are presented for a series of fire-suppression tests conducted in a full-scale nacelle along with the results of pretest predictions carried out using the Vulcan fire-physics simulation code. The purpose of these tests was to assess the utility of
The current paper introduces a facility to be used for the investigation of fire suppressant transport and pool fire extinction in an environment similar to an aircraft engine nacelle. This work is done as part of an ongoing effort to develop a suppressant
The effects of oxidizer stream velocity and oxygen concentration, as well as gravity and pressure, on the extinguishment limits of laminar co-flow diffusion flames of methane, formed in a cup-burner apparatus, have been studied experimentally and
Nanocomposites based on three different shapes of nanoscale particles, sphere (silica), plate (clay), and tube (carbon nanotube), were prepared and the dispersion of the particles in the nanocomposites was confirmed by various techniques using TEM, SEM
E Samson, J Marchand, Kenneth A. Snyder, J J. Beaudoin
A description of ionic transport in unsaturated porous materials due to gradients in the electro-chemical potential and the moisture content is developed by averaging the relevant microscopic transport equations over a representative volume element. The
CF3I has been considered to be a candidate replacement of CF3Br used in aircraft for fuel inerting and for fire fighting. In this study, the chemical effects of aircraft released CF3I on atmospheric ozone were examined with the current UIUC 2D Chemical
Previously, it has been suggested that in low water-to-cement ratio (w/c) concretes, the coarser cement particles could be replaced by an inert filer with little loss in performance in terms of hydration and strength development. This communication
Geraldine S. Cheok, William C. Stone, Alan M. Lytle
This paper presents a discussion of standards requirements for LADAR. Two specific questions are addressed: (1) is there a need for such standards and (2) what types of standards are required? LADAR standards development issues and current standardization