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Jiann C. Yang, Thomas G. Cleary, Michelle K. Donnelly
Tritluoroiodomethane (CF3I) has been proposed as a potential replacement for Halon 1301 in aircraft engine nacelle and dry bay fire protection applications. The potential use of CF3I in fuel tank ullage inerting has also been considered recently. Before
Erik L. Johnsson, George W. Mulholland, Gerald T. Fraser, A Zuban, I I. Leonov
There is a need for monitoring the concentration of potential halon replacement chemicals with millisecond response time [I]. One scenario of great concern to the Air Force is the penetration of an enemy shell into the fuel tank of an aircraft. To prevent
Exploratory research has indicated that the following chemical families are likely 10 contain chemicals possessing both a high degree of fire suppression efficiency and low environmental impact: the bromoalkenes, bromoethers, and phosphorus-containing
Although fiber reinforced polymer (FRP) composites are increasingly being used for the renewal of civil infrastructure, there are still some major questions related to the durability of these materials in a civil engineering environment. This concern is
A review of the computer program 4sight has revealed that an accurate prediction of water transport through the concrete depends upon an accurate prediction of the crack formation within the concrete. A model for predicting both the width and the spacing
J D. Shane, T Mason, D A. Jennings, Edward Garboczi, Dale P. Bentz
The electrical conductivity of portland cement mortars was determined experimentally as a function of the volume fraction of sand and degree of hydration. The results were analyzed using theoretical models that represent the mortars as three-phase
While the strength and durability of high performance concretes (HPCs) are often greatly superior to conventional concretes under ambient conditions, their failure is sometimes rapid and dramatic during exposure to a fire, characterized by the explosive
A compilation of fire test data which shows distinct behaviroal differences between HSC and NSC at elevated temperature is presented. The differences are most pronounced in the temperature range of 20 {degrees}C to 400 {degrees}C. What is more important is
This document is derived from three reviewed papers by the same authors: (1)Elastic properties of a tungsten-silver composite by reconstruction and computation; (2)Elastic properties of model porous ceramics; and (3)Elastic properties of model random three
In the last 30 years, the compressive strength of concrete that can be produced reliably in the field has more than doubled, from 35 MPa (5000 psi) to 85 MPa (12 000 psi). Strengths as high as 140 MPa (20 000 psi) can be achieved in the laboratory and, on
Walter J. Rossiter Jr, M Vangel, M E. McKnight, G Dewalt
A laboratory study was conducted to determine the reliability of spot test kits for detecting the presence of lead in household paint when tests were conducted by certified lead inspectors or risk assessors. Reagent solutions were applied to paint
Smokeview is a software tool designed to visualize numerical predictions generated by the NIST Fire Dynamics Simulator (FDS). FDS is a computational fluid dynamics (CFD) model of fire-driven fluid flow. These two tools are used in concert to respectively
This report describes the results of calculations using the NIST Fire Dynamics Simulator (FDS) that were performed to provide insight on the thermal conditions that may have occurred during the fire at 3146 Cherry Road NE, Washington D.C. on May 30, 1999
A public/private partnership involving multiple federal agencies and private industry was assembled to develop a comprehensive fire investigation training tool. The partnership consisted of the following federal agencies: the Bureau of Alcohol, Tobacco and
J E. Seem, J House, George E. Kelly, C J. Klaassen
Traditional air-handling unit (AHU) control systems link the position of the exhaust, recirculation and outdoor air dampers. Laboratory tests of a variable-air-volume AHU using the traditional damper control approach revealed that outdoor air could enter
This user's manual provides updated documentation and computer program listings for version 2.0 of the three-dimensional cement hydration and microstructure development model (CEMHYD3D) developed at the National Institute of Standards and Technology
Paul E. Stutzman, Germain Lespinasse, Stefan D. Leigh
Certification of the phase compositions of the NIST Reference Clinkers often is based upon more than one independent method. The current certificate values were established using an optical microscope examination, and additional microscope data taken from
The impedance response of conductive fiber-reinforced cement-based materials was investigated using model systems (physical simulations) consisting of conducting needles in aqueous solutions. Two discrete bulk arcs are observed in the Nyquist plots for
D T. Raghavan, Xiaohong Gu, Tinh Nguyen, Mark R. VanLandingham, Alamgir Karim
Polymer coatings contain degradation-susceptible regions, and corrosion of metallic substrate can occur directly underneath these regions. In this paper, the microstructure of model coating materials is investigated using atomic force microscopy (AFM)
An experimental program was undertaken to evaluate methods to retrofit existing steel moment connections for improved seismic performance. Six full-scale subassemblages were tested under cyclic loading. Typical pre-Northridge connections were retrofit by