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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
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
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
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
Terrence J. Jach, A S. Bakulin, S M. Durbin, J Pedulla, A T. Macrander
We describe the distinction between the operation of a short focal lengthx-ray microscope forming a real image with a laboratory source (convergentillumination) and with a highly collimated intense beam from a synchrotronlight source (K\{o}hler
Malgorzata Kopycinska-Mueller, Roy H. Geiss, Donna C. Hurley
We are developing dynamic atomic force microscopy (AFM) techniques to determine nanoscale elastic properties. Atomic force acoustic microscopy (AFAM) makes use of the resonant frequencies of an AFM cantilever while its tip contacts the sample surface at a
Ward L. Johnson, Colm Flannery, Sudook A. Kim, Roy H. Geiss, Christopher Soles, Paul R. Heyliger
Experimental techniques employing Brillouin light scattering (BLS) and analytical techniques employing finite-element (FE) and Farnell-Adler models are being developed for characterizing acoustic modes and determining elastic moduli and dimensions of
Donna C. Hurley, Malgorzata Kopycinska-Mueller, D Julthongpiput, Michael J. Fasolka
The effects of surface functionality and relative humidity (RH) on nanomechanical properties were investigated using atomic force acoustic microscopy (AFAM), a contact scanned probe microscopy (SPM) technique. Self-assembled monolayers (SAMs) with
Ion-implanted materials are commonly used in secondary-ion mass spectrometry for the calibration of instruments. This international Standard was prepared to provide a uniform method for determining the relative sensitivity factor (RSF) of an element in a
T B. Copelen, W Brand, M Gehre, M Groening, HAJ Meijer, Blaza Toman, R. Michael Verkouteren
We present state-of-the-art measurements and data evaluation methods to show that the consistency of carbon isotope ratio measurements can be improved 39 % to 47 % by anchoring the measurement scale with two isotopic reference materials differing in carbon
Marlon L. Walker, Lee J. Richter, Daniel Josell, Thomas P. Moffat
The adsorption of PEG-Cl on a.) air-oxidized Ru, b.) reduced or activated Ru and c.) underpotential deposited (upd) Cu on activated Ru was examined in-situ using spectroscopic ellipsometry. In the absence of Cl- ion, PEG adsorption was minimal at all
R Dobbins, Robert A. Fletcher, Bruce A. Benner Jr., S Hoeft
Numerous chemical analyses of gaseous and particulate samples from laboratory flames provide a library of data on the polycyclic aromatic hydrocarbons (PAH) species found in diverse flame types burning fuels consisting of pure gaseous hydrocarbons. Diesel
A simplified method for the preparation of particles from liquid suspensions has been developed. Particles are deposited directly on carbon planchets for rapid analysis by environmental scanning electron microscopy or by conventional scanning electron
Donna C. Hurley, Malgorzata Kopycinska-Mueller, Tony B. Kos, Roy H. Geiss
We describe a dynamic atomic force microscopy (AFM) method to measure the nanoscale elastic properties of surfaces, thin films, and nanostructures. Our approach is based on atomic force acoustic microscopy (AFAM) techniques and involves the resonant modes
Jennifer R. Verkouteren, John G. Gillen, R M. Verkouteren, Robert A. Fletcher, E S. Etz, George A. Klouda, Alim A. Fatah, Philip J. Mattson
The purpose of this document is to establish minimum performance requirements and an associated test method for Ion Mobility Spectrometry (IMS) based trace explosives detectors for use by the first responder community. Information concerning the theory and
Malgorzata Kopycinska-Mueller, Roy H. Geiss, Donna C. Hurley
Stiffness-load curves obtained in quantitative atomic force acoustic microscopy (AFAM) measurements depend on both the elastic properties of the sample and the geometry of the atomic force microscope (AFM) tip. The geometry of silicon AFM tips changes when
Donna C. Hurley, Malgorzata Kopycinska-Mueller, Tony B. Kos, Roy H. Geiss
We are developing metrology for rapid, quantitative assessment of elastic porperties with nanoscale spatial resolution. Atomic force acoustic microscopy (AFAM) methods enable modulus measurements at either a single point or as a map of local property
Polymeric blends comprised of the biodegradable polymer poly-L-lactic acid (PLLA) and polyethylene oxide (PEO) are of considerable interest due to their potential applications as protein drug delivery devices. In such devices, the PEO component will
Stephanie A. Hooker, Jens Mueller, Clayton Kostelecky, K. Womer
Piezoelectric ceramics are desirable actuator materials for many biomedical applications due to their ability to generate precise, controlled motion with applied voltage. Herein, we report the fabrication of miniature piezoelectric ceramic actuators and
Donna C. Hurley, Roy H. Geiss, N Jennett, Malgorzata Kopycinska-Mueller, A Maxwell, Jens Mueller, David T. Read, J Wright
We describe two acoustical methods to evaluate the mechanical properties of thin films and nanoscale structures: atomic force acoustic microscopy and surface acoustic wave spectroscopy. The elastic properties of an 800-nm-thick nickel film were examined
Marlon L. Walker, Lee J. Richter, Thomas P. Moffat
Spectroscopic ellipsometry was used to examine the adsorption of polyethylene glycol (PEG) and Cl- on polycrystalline Cu, Ag and Au electrodes in sulfuric acid. In halide-free sulfuric acid, PEG adsorption on Cu and Ag is minimal at potentials positive of
The MSEL Nanometrology Program incorporates basic measurement metrologies to determine material properties, process monitoring at the nanoscale, nano-manufacturing and fabrication techniques, and structural characterization and analysis techniques, such as