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Displaying 18051 - 18075 of 74071

M 2 (m-dobdc) (M=Mg,Mn, Fe, Co, Ni) Metal-Organic Frameworks Exhibiting Increased Charge Density and Enhanced H 2 Binding at the Open Metal Sites

August 14, 2014
Author(s)
Matthew T. Kapelewski, Stephen J. Geier, Matthew Ross Hudson, David Stuck, Jarad A. Mason, Jocienne N. Nelson, Zeric Z. Hulvey, Elizabeth Gilmour, Stephen A. FitzGerald, Martin Head-Gordon, Craig Brown, Jeffrey R. Long
Metal-organic frameworks are a class of microporous materials that are being heavily investigated for their hydrogen storage properties due to their high internal surface areas and strong interactions with adsorbed gases. Increasing they hydrogen binding

Modeling of 2-bromotrifluoropropene flame inhibition

August 14, 2014
Author(s)
Donald R. Burgess Jr., Jeffrey A. Manion, Valeri I. Babushok, Gregory T. Linteris
We developed a new chemical mechanism for modeling flame inhibition by 2-bromotrifluoropene (2-BTP). The modeling results qualitatively predicted agent behavior in cup-burner and FAA Aerosol Can tests over a wide range of conditions. The ban on igh ozone

Reducing oscillator PM noise from AM-PM noise correlaiton

August 14, 2014
Author(s)
Archita Hati, Craig W. Nelson, David A. Howe
We present a new scheme for improving the phase modulated (PM) noise of an oscillator from correlation between amplitude modulated (AM) and PM noise. Experimental results of this correlation effect are presented. An improvement of almost 10 dB in the PM

Stochastic Regression Modeling of Chemical Spectra

August 14, 2014
Author(s)
Anthony J. Kearsley, William E. Wallace, Yutheeka Gadhyan
A stochastic regression method has been developed that decomposes chemical spectra into separate contributions from signal and from noise. The numerical results of regressing in this way on sample spectra are presented. The results suggest that this

Vibronic Coupling in Asymmetric Bichromophores: Experimental Investigation of Diphenylmethane-d5

August 14, 2014
Author(s)
Nathan Pillsbury, Nathanael M. Kidwell, Benjamin Nebgen, Lyudmila V. Slipchenko, Kevin O. Douglass, John R. Cable, David F. Plusquellic
Vibrationally and rotationally resolved electronic spectra of diphenylmethane-d5 (DPM-d5) are reported in the isolated-molecule environment of a supersonic expansion. While small, the asymmetry induced by deuteration of one of the aromatic rings is

The Half-Life of 209Po : Revisited

August 13, 2014
Author(s)
Ronald Colle, Ryan P. Fitzgerald, Lizbeth Laureano-Perez
A substantial 25 % error in the then known and accepted (102  5) year half-life of 209Po was reported on in 2007. This error was detected from decay data from two separate primary standardizations of a 209Po solution standard, which were performed

Effects of Lateral Tip Control in CD-AFM Width Metrology

August 12, 2014
Author(s)
Ronald G. Dixson, Boon Ping Ng, Ndubuisi G. Orji
Critical dimension atomic force microscopes (CD-AFMs) use flared tips and two-dimensional sensing and position control of the tip-sample interaction to enable scanning of features with near-vertical or reentrant sidewalls. Sidewall sensing usually involves

EUV spectra of Rb-like to Ni-like dysprosium ions in an electron beam ion trap

August 12, 2014
Author(s)
Deirdre Kilbane, G. O'Sullivan, Yuri A. Podpaly, John D. Gillaspy, Joseph Reader, Yuri Ralchenko
Extreme ultraviolet radiation emitted from highly-charged dysprosium ions was measured at the National Institute of Standards and Technology. The ions were created, trapped, and excited in an electron beam ion trap (EBIT), and the spectra were recorded

Ordered Structure and Thermal Expansion in Tungsten Bronze Pb 2 K 0.5 Li 0.5 Nb 5 O 15

August 12, 2014
Author(s)
Kun Lin, Yangchun Rong, Hui Wu, Qingzhen Huang, Li You, Yang Ren, Longlong Fan, Jun Chen, Xianran Xing
The crystal structure and thermal expansions of a new tetragonal tungsten bronze (TTB) ferroelectrics Pb 2K 0.5Li 0.5Nb 5O 15 were systematically investigated by selected area electron diffraction (SAED), neutron powder diffraction, synchrotron XRD, and

Toward Metamodels for Composable and Reusable Additive Manufacturing Process Models

August 12, 2014
Author(s)
Paul W. Witherell, Shaw C. Feng, Timothy Simpson
Despite the existence and interest in additive manufacturing (AM) for many decades, industry adoption of AM technologies has been relatively slow. Recent advances in modeling and simulation of AM processes and materials are providing new insights to help

Performance Benchmarking and Intensity Calibration of a Widefield Fluorescence Microscope Using Fluorescent Glass

August 11, 2014
Author(s)
Michael W. Halter, Elianna Bier, Paul C. DeRose, Gregory A. Cooksey, Steven J. Choquette, Anne L. Plant, John T. Elliott
Widefield fluorescence microscopy is a highly used tool for visually assessing biological samples and for quantifying cell responses. Despite its widespread use in high content analysis and other screening applications, few published methods exist for

XForms User Interfaces for Small Arcane Nontrivial Datasets

August 11, 2014
Author(s)
Joshua Lubell
Small Arcane Nontrivial Datasets (SANDs) are frequently complex enough to warrant custom software for access and editing, yet too small or specialized to justify a fullblown server-based database application. Such data is typically presented in tabular

Attachment of a Reduction-Oxidative Active Diruthenium Compound to Au and Si Surfaces by “Click” Chemistry

August 10, 2014
Author(s)
Sujitra J. Pookpanratana, Joseph W. Robertson, Curt A. Richter, Christina A. Hacker, Lee J. Richter, Julia Savchenko, Steven Cummings, Tong Ren
We report the formation of molecular monolayers containing redox-active diruthenium(II,III) compound to gold and silicon surfaces via “click” chemistry. The use of Cu-catalyzed azide-alkyne cycloaddition enables modular design of molecular surfaces and

Compressed-liquid density measurements of three alternative turbine fuels

August 10, 2014
Author(s)
Stephanie L. Outcalt
Heavier kerosene based liquid fuels for aircraft and rockets are required to meet stringent performance specifications. Nevertheless, the escalating cost, unpredictable supply, and environmental impacts of traditional petroleum based fuels used for that

Infiltration in energy modeling: a simple equation made better

August 8, 2014
Author(s)
Lisa C. Ng, Andrew K. Persily, Steven J. Emmerich
As building envelope performance and HVAC equipment efficiencies continue to be improved to reduce building energy use, a greater percentage of the total energy loss of a building can occur through envelope leakage. Although the energy impacts of

Measurement of High-Energy (10 keV to 60 keV) X-Ray Spectral Line Widths with eV Accuracy

August 8, 2014
Author(s)
John F. Seely, Jack L. Glover, Lawrence T. Hudson, Yuri Ralchenko, Nino R. Pereira, U. Feldman, C. D. Stefan
A high resolution crystal spectrometer (HRCS) utilizing a crystal in transmission geometry has been developed and experimentally optimized to measure the line widths of emission lines in the 10 keV to 60 keV energy range with eV accuracy. The spectrometer

Optically-Pumped Magnetometers for MEG

August 8, 2014
Author(s)
Svenja A. Knappe, Tillman H. Sander, Lutz Trahms
Optically-pumped magnetometers (OPMs) have seen rapid progress over the last decade in terms of performance and technology development. As highly sensitive room-temperature magnetometers they present several advantages over SQUID sensors, such as the

Single-Mode Optical Fiber For High-Power, Low-Loss UV Transmission

August 8, 2014
Author(s)
Daniel H. Slichter, Yves Colombe, Andrew C. Wilson, Dietrich G. Leibfried, David J. Wineland
We report large-mode-area solid-core photonic crystal fibers made from fused silica which resist UV solarization even at relatively high optical powers. Using a process of hydrogen loading and UV irradiation of the fibers, we demonstrate stable single-mode

Speckle phase noise in coherent laser ranging: fundamental precision limitations

August 8, 2014
Author(s)
Esther Baumann, Jean-Daniel Deschenes, Fabrizio R. Giorgetta, William C. Swann, Ian R. Coddington, Nathan R. Newbury
Frequency-modulated continuous-wave laser detection and ranging (FMCW LADAR) measures the range to a surface through coherent detection of the backscattered light from a frequency-swept laser source. The ultimate limit to the range precision of FMCW LADAR

Anion Reorientations in the Superionic Conducting Phase of Na 2 B 12 H 12

August 7, 2014
Author(s)
Kristina Verdal, Terrence J. Udovic, Vitalie Stavila, Wan Si NMN Tang, John J. Rush, Alexander V. Skripov
Quasielastic neutron scattering (QENS) methods were used to characterize the reorientational dynamics of the dodecahydro-closo-dodecaborate (B 12H 126u2-^0 anions in the high-temperature, superionic conducting phase of na 2B 12H6d12^. The icosahedral

Flow Cytometer Performance Characterization, Standardization and Calibration against CD4 on T Lymphocytes Enables Quantification of Biomarker Expressions for Immunological Applications

August 7, 2014
Author(s)
Heba Degheidy, Steven R. Bauer, Gerald Marti, Lili Wang
There is an urgent need for developing a procedure for biomarker standardization and quantification in clinical laboratories. Measuring the expression levels of cell antigens is critical for the diagnosis of many diseases, e.g. leukemia, lymphoma and
Displaying 18051 - 18075 of 74071