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Characterization and Ion-Induced Degradation of Cross-Linked Poly(Methyl Methacylate) Studies Using Time of Flight Secondary Ion Mass Spectrometry

December 30, 2006

Author(s)

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

Part B Measurement Methods for Composition and Structure

December 16, 2006

Author(s)

Willie E. May

Measurement Methods for Composition and Structure

Improvements in the Measurement of Distillation Curves: Part 3 - Application to Gasoline and Gasoline + Methanol Mixtures

December 8, 2006

Author(s)

Beverly L. Smith, Thomas J. Bruno

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)

After Two Decades a Second Anchor for the VPDB delta-13-C Scale

November 15, 2006

Author(s)

T.B. Coplen, W.A. Brand, M. Gehre, M. Groning, H.A.J. Meijer, Blaza Toman, R. Michael Verkouteren

Competitive Adsorption of PEG, CI - , and SPS/MPS on Cu: An In Situ Ellipsometric Study

August 1, 2006

Author(s)

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

NIST Calibration Services for Water Flowmeters Water Flow Calibration Facility

August 1, 2006

Author(s)

Iosif I. Shinder, Iryna V. Marfenko

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

Methane-water cross second virial coefficient with quantum corrections from an ab initio potential

July 6, 2006

Author(s)

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

3D Molecular Imaging SIMS

July 1, 2006

Author(s)

John G. Gillen, Albert J. Fahey, M Wagner, Christine M. Mahoney

Thin monolayer and bilayer filsm of spin cast poly(methyl methacrylate) (PMMA), poly(2-hydroxyethyl methacrylate) (PHEMA), poly(lactic) acid (PLA) and PLA doped with several pharmaceuticals have been analyzed by dynamic SIMS using SF 5+ polyatomic primary

Characterization of Drug-Eluting Stent (DES) Materials With Cluster Secondary Ion Mass Spectrometry (SIMS)

July 1, 2006

Author(s)

Christine M. Mahoney, Martin McDermott

Secondary Ion Mass Spectrometry (SIMS) employing an SF5+ polyatomic primary ion source was utilized to analyze several materials commonly used in drug eluting stents (DES). Poly(ethylene-co-vinyl acetate) (PEVA), Poly(lactic-co-glycolic acid) (PLGA) and

Evaluation of the Shapes of Auger- and Secondary-Electron Linescans Across Interfaces With the Logistic Function

July 1, 2006

Author(s)

Scott A. Wight, Cedric J. Powell

We report on the use of the extended logistic function for fitting Auger-electron (AE) and secondary-electron (SE) linescans. Such fits provide convenient and objective measures of parameters describing the interface width and possible asymmetry of a

SIMS Depth Profiling of Polymer Blends With Protein Based Drugs

July 1, 2006

Author(s)

Christine M. Mahoney, J Yu, Albert J. Fahey, J Gardella

The use of SF5+ cluster ions for depth profiling has been successful for polymer-drug mixtures and polymer blends. This study reports results of the surface and in-depth characterization of two component blend films of poly(L-lactic acid) (PLLA) and

Temperature-Controlled Depth Profiling in Polymeric Biomaterials Using Cluster Secondary Ion Mass Spectrometry

July 1, 2006

Author(s)

Christine M. Mahoney, Albert J. Fahey, John G. Gillen, Chang Xu, J Batteas

Secondary Ion Mass Spectrometry (SIMS) employing an SF5+ polyatomic primary ion source was used to depth profile through various polymeric biomaterials at a series of temperatures from -125 oC to 150 oC. The depth profile characteristics (e.g. interfacial

Characterization of Inertance Tubes Using Resonance Effects

June 14, 2006

Author(s)

Michael A. Lewis, Peter E. Bradley, Ray Radebaugh, Zhihua Gan

Inertance tubes can be characterized by their inertance, compliance, and resistance. All three of these impedance components are present during normal measurements of inertance tube impedance. As a result, in comparing experimental results with models it

Improvements in the Measurement of Distillation Curves - Part 1: A Composition-Explicit Approach

June 7, 2006

Author(s)

Thomas J. Bruno

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

Improvements in the Measurement of Distillation Curves - Part 2: Application to Aerospace/Aviation Fuels RP-1 and S-8

June 7, 2006

Author(s)

Thomas J. Bruno, Beverly L. Smith

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

Development and Evaluation of Methods for Determination of Naphthodianthrones and Flavonoids in St. John's Wort

May 19, 2006

Author(s)

F. B. Williams, Lane C. Sander, Stephen Wise, J. Girard

Development and Evaluation of Methods for Development of Naphthodianthrones and Flavonoids in St. John s Wort

May 19, 2006

Author(s)

F. B. Williams, Lane C. Sander, Stephen Wise, J. Girard

Several major constituents in St. John s Wort were determined for a homogenized plant sample. Three extraction techniques were evaluated: Soxhlet extraction, pressurized fluid extraction and sonication extraction. Levels of nine constituents (chlorogenic

Quantum Dot Dissemination and Behavior in Bacterial Biofilms

May 7, 2006

Author(s)

Jayne B. Morrow, Richard D. Holbrook, Cynthia J. Zeissler

Quantum dots (QDs) are colloidal semiconductor nanocrystals that photoluminescence emission is proportional to the dot size and have been utilized in fluorescent imaging in biological systems. Biofilms are communities of microorganisms attached to surfaces

Correlation for the Viscosity of Pentafluoroethane (R125) from the Triple Point to 500 K at Pressures up to 60 MPa.

May 5, 2006

Author(s)

Marcia L. Huber, Arno R. Laesecke

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

A Reference Standard for Measuring Humidity of Air Using a Re-entrant Radio Frequency Resonator

May 2, 2006

Author(s)

Peter H. Huang, Dean C. Ripple, Michael R. Moldover, Gregory E. Scace

We developed a stable reference hygrometer suitable for operation at temperatures above ambient that has a robust design, inherent stability, and a well-understood theory of measurement. This hygrometer uses a reentrant, radio-frequency, cavity resonator

Regenerator Operation at Very High Frequencies for Microcryocoolers

April 27, 2006

Author(s)

Ray Radebaugh, Agnes A. O'Gallagher

The size of Stirling and Stirling-type pulse tube cryocoolers is dominated by the size of the pressure oscillator. Such cryocoolers typically operate at frequencies up to about 60 Hz for cold-end temperatures above about 60 K. Higher operating frequencies