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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
Buckmins erfullerene ion beam has been applied o he dep h profiling of an al erna ing pure P and pure Co mul ilayer. Quan i a ive dep h profiling was performed by secondary ion mass spec rome ry (SIMS) wi h C60 ions using P Co alloy films wi h differen
Robert D. Chirico, Russell D. Johnson III, William Steele
Measurements leading to the calculation of the standard thermodynamic properties for gaseous 2,6-dimethylquinoline (Chemical Abstracts registry number [877-43-0]) are reported. Experimental methods included adiabatic heat-capacity calorimetry, vibrating
Vibrational zero-point energies (ZPEs), as determined from published spectroscopic constants, are derived for 85 diatomic molecules. Standard uncertainties are also provided, including estimated contributions from bias as well as the statistical
David Point, William C. Davis, Steven J. Christopher, Michael B. Ellisor, Rebecca S. Pugh, Olivier F. Donard, Paul R. Becker, Barbara J. Porter, Stephen A. Wise
Automated peak identification in electron beam excited x-ray microanalysis with energy dispersive x-ray spectrometry is subject to occasional mistakes even on well separated, high intensity peaks arising from major constituents. The problem is exacerbated
Yi-Lei Zhao, Stephen L. Garrison, Carlos A. Gonzalez, William D. Thweatt, M Marquez
Gas-phase nitrosation implies an alternative non-ionic pathway different from the nitrosonium-nitrosation by acidification of nitrite. Electronic structure calculations discussed in this work suggest a free radical mechanism, in which NO2 abstracts a
M Colket, T Edwards, S Williams, N Cernansky, D L. Miller, Fokion N. Egolfopoulos, P Linstedt, Ram Seshadri, F L. Dryer, C K. Law, Daniel G. Friend, David Lenhert, Heinz Pitsch, A Sarofim, M Smooke, Wing Tsang
The engineering and scientific community ha been searching for the identification of surrogate fuels that can reasonably represent the performance and emissions behavior of jet fuels (e.g. Jet A and JP-8) in engines. Many proposals exist in the literature
The chemical analysis of process streams is a common task that must be completed thousands of times every day in the chemical industry. In refineries, at gas wells, in chemical processing plants and in fine pharmaceutical facilities, there is a continual
Dianne L. Poster, Thanh H. Nguyen, Roberta A. Brown, William P. Ball
Sorption isotherms for five aromatic hydrocarbons were obtained with a natural wood char (NC1) and its residue after solvent extraction (ENC1). Substantial isotherm nonlinearity was observed in all cases. ENC1 showed higher BET surface area, higher
Srinivas Vanapalli, Michael A. Lewis, Zhihua Gan, Ray Radebaugh
A pulse tube cryocooler operating at 120 Hz with 3.5 MPa average pressure achieved a no-load temperature of about 49.9 K and a cooldown time to 80 K of 5.5 minutes. The net refrigeration power at 80 K was 3.35 W with an efficiency of about 22.6% of Carnot
Commercial pepper sprays devices deliver a coherent liquid stream or an aerosol from a pressurized canister. It is likely that some of the droplets from the aerosol-type pepper sprays inhaled during its use to assist in subduing individuals resisting
Christine M. Mahoney, Albert J. Fahey, John G. Gillen, Chang Xu, James Batteas
Secondary Ion Mass Spectrometry (SIMS) employing an SF polyatomic primary ion source was used to depth profile Poly(methyl methacrylate) (PMMA) at a series of temperatures from -75 C to 125 C where the primary glass transition for PMMA occurs at 105 C. The
Christine M. Mahoney, Albert J. Fahey, John G. Gillen
Secondary Ion Mass Spectrometry (SIMS) employing an SF5+ polyatomic primary ion source was used to depth profile Poly(methyl methacrylate) (PMMA) at a series of temperatures from -75 oC to 125 oC, where the primary glass transition for PMMA occurs at 105
The design of any process involving supercritical fluids requires some degree of knowledge about the thermophysical and chemical properties of the solvents, solutes and of the solvent + solute mixture. This knowledge can take the form of measured data
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
Cynthia J. Zeissler, Keana C. Scott, Richard D. Holbrook, Peter E. Barker, Yan Xiao
We are exploring methods to achieve 3D 200 nm resolution multispectral imaging with an ordinary inexpensive widefield microscope using incoherent white light sources and an electronically tunable filter. In this work, the capabilities were applied to
M S. Wagner, K Lenghaus, John G. Gillen, Michael J. Tarlov
In this study, a series of random copolymers of methyl methacrylate (MMA) and ethylene glycol dimethacrylate (EGDMA) were prepared as surface-initiated polymer (SIP) films on silicon substrates using atom transfer radical polymerization. Positive and
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)
Marlon L. Walker, Lee J. Richter, Thomas P. Moffat
The adsorption of Cu electrodeposition accelerating agents SPS and MPS on evaporated Cu thin films was examined in-situ using spectroscopic ellipsometry under quiescent conditions. Both the thiol (MPS) and disulfide (SPS) resulted in definitive changes in
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
Omololu Akin-Ojo, Allan H. Harvey, Krzysztof Szalewicz
We present our calculations of the cross second virial coefficient (B12) and of a related quantity, (phi)12 = B12 - TdB12/dT, for the methane?water system in the temperature range T = 200 - 1000 K. These calculations were performed using one of the ab