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Increasing FTIR spectromicroscopy speed and resolution through compressive imaging

Description: At the Advanced Light Source at Lawrence Berkeley National Laboratory, we are investigating how to increase both the speed and resolution of synchrotron infrared imaging. Synchrotron infrared beamlines have diffraction-limited spot sizes and high signal to noise, however spectral images must be obtained one point at a time and the spatial resolution is limited by the effects of diffraction. One technique to assist in speeding up spectral image acquisition is described here and uses compressive … more
Date: October 15, 2007
Creator: Gallet, Julien; Riley, Michael; Hao, Zhao & Martin, Michael C
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Spatial resolution limits for synchrotron-based infrared spectromicroscopy

Description: Detailed spatial resolution tests were performed on beamline 1.4.4 at the Advanced Light Source synchrotron facility in Berkeley, CA. The high-brightness synchrotron source is coupled at this beamline to a Thermo-Electron Continumum XL infrared microscope. Two types of resolution tests in both the mid-IR (using a KBr beamsplitter and an MCT-A* detector) and in the near-IR (using a CaF2 beamsplitter and an InGaAS detector) were performed and compared to a simple diffraction-limited spot size mod… more
Date: October 15, 2007
Creator: Levenson, Erika; Lerch, Philippe & Martin, Michael C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

ACRF Instrumentation Status: New, Current, and Future - September 2008

Description: The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following five sections: (1) new instrumentation in the process of being acquired and deployed, (2) field campaigns, (3) existing instrumentation and progress on improvements or upgrades, (4) proposed future instrumentation, and (5) Small Business Innovation Research instrument development.
Date: October 15, 2008
Creator: Voyles, J. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Analysis of Non-Enzymatically Glycated Peptides: Neutral-Loss Triggered MS3 Versus Multi-Stage Activation Tandem Mass Spectrometry

Description: Non-enzymatic glycation of tissue proteins has important implications in the development of complications of diabetes mellitus. While electron transfer dissociation (ETD) has been shown to outperform collision-induced dissociation (CID) in sequencing glycated peptides by tandem mass spectrometry, ETD instrumentation is not yet available in all laboratories. In this study, we evaluated different advanced CID techniques (i.e., neutral-loss triggered MS3 and multi-stage activation) during LC-MSn a… more
Date: October 15, 2008
Creator: Zhang, Qibin; Petyuk, Vladislav A.; Schepmoes, Athena A.; Orton, Daniel J.; Monroe, Matthew E.; Yang, Feng et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Modeling of Carbon Migration During JET Injection Experiments

Description: JET has performed two dedicated carbon migration experiments on the final run day of separate campaigns (2001 and 2004) using {sup 13}CH{sub 4} methane injected into repeated discharges. The EDGE2D/NIMBUS code modelled the carbon migration in both experiments. This paper describes this modelling and identifies a number of important migration pathways: (1) deposition and erosion near the injection location, (2) migration through the main chamber SOL, (3) migration through the private flux region… more
Date: October 15, 2008
Creator: Strachan, J. D.; Likonen, J.; Coad, P.; Rubel, M.; Widdowson, A.; Airila, M. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Development and Integration of Hardware and Software for Active-Sensors in Structural Monitoring

Description: Structural Health Monitoring (SHM) promises to deliver great benefits to many industries. Primarily among them is a potential for large cost savings in maintenance of complex structures such as aircraft and civil infrastructure. However, several large obstacles remain before widespread use on structures can be accomplished. The development of three components would address many of these obstacles: a robust sensor validation procedure, a low-cost active-sensing hardware and an integrated softwar… more
Date: October 15, 2007
Creator: Overly, Timothy G.S.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Detection of low energy single ion impacts in micron scaletransistors at room temperature

Description: We report the detection of single ion impacts throughmonitoring of changes in the source-drain currents of field effecttransistors (FET) at room temperature. Implant apertures are formed inthe interlayer dielectrics and gate electrodes of planar, micro-scaleFETs by electron beam assisted etching. FET currents increase due to thegeneration of positively charged defects in gate oxides when ions(121Sb12+, 14+, Xe6+; 50 to 70 keV) impinge into channel regions. Implantdamage is repaired by rapid the… more
Date: October 15, 2007
Creator: Batra, A.; Weis, C. D.; Reijonen, J.; Persaud, A.; Schenkel, T.; Cabrini, S. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

John Pendry: His Contributions to the Development of LEED Surface Crystallography

Description: In this paper we discuss the pivotal role played by Sir John Pendry in the development of Low Energy Electron Diffraction (LEED) during the past three decades; the earliest understanding on the physics of LEED to the development of sophisticated methods for the structural solution of complex surfaces.
Date: October 15, 2007
Creator: Somorjai, Gabor A. & Rous, P. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The National Ignition Facility: The world's largest optical system

Description: The National Ignition Facility (NIF), a 192-beam fusion laser, is presently under construction at the Lawrence Livermore National Laboratory with an expected completion in 2008. The facility contains 7,456 meter-scale optics for amplification, beam steering, vacuum barriers, focusing, polarization rotation, and wavelength conversion. A multiphase program was put in place to increase the monthly optical manufacturing rate by up to 20x while simultaneously reducing cost by up to 3x through a sub-… more
Date: October 15, 2007
Creator: Stolz, C J
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Hydrogen Production and Delivery Research

Description: In response to DOE's Solicitation for Grant Applications DE-PS36-03GO93007, 'Hydrogen Production and Delivery Research', SRI International (SRI) proposed to conduct work under Technical Topic Area 5, Advanced Electrolysis Systems; Sub-Topic 5B, High-Temperature Steam Electrolysis. We proposed to develop a prototype of a modular industrial system for low-cost generation of H{sub 2} (<$2/kg) by steam electrolysis with anodic depolarization by CO. Water will be decomposed electrochemically into… more
Date: October 15, 2007
Creator: Balachov, Iouri
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Oak Ridge National Laboratory Annual Progress Report for the Power Electronics and Electric Machinery Program

Description: The U.S. Department of Energy (DOE) and the U.S. Council for Automotive Research (composed of automakers Ford, General Motors, and Chrysler) announced in January 2002 a new cooperative research effort. Known as FreedomCAR (derived from 'Freedom' and 'Cooperative Automotive Research'), it represents DOE's commitment to developing public/private partnerships to fund high-risk, high-payoff research into advanced automotive technologies. Efficient fuel cell technology, which uses hydrogen to power … more
Date: October 15, 2008
Creator: Olszewski, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Porphyrin-Based Photocatalytic Lithography

Description: Photocatalytic lithography is an emerging technique that couples light with coated mask materials in order to pattern surface chemistry. We excite porphyrins to create radical species that photocatalytically oxidize, and thereby pattern, chemistries in the local vicinity. The technique advantageously does not necessitate mass transport or specified substrates, it is fast and robust and the wavelength of light does not limit the resolution of patterned features. We have patterned proteins and ce… more
Date: October 15, 2007
Creator: Bearinger, J.; Stone, G.; Christian, A.; Dugan, L.; Hiddessen, A.; Wu, K. J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Computer Experiments for Function Approximations

Description: This research project falls in the domain of response surface methodology, which seeks cost-effective ways to accurately fit an approximate function to experimental data. Modeling and computer simulation are essential tools in modern science and engineering. A computer simulation can be viewed as a function that receives input from a given parameter space and produces an output. Running the simulation repeatedly amounts to an equivalent number of function evaluations, and for complex models, su… more
Date: October 15, 2007
Creator: Chang, A; Izmailov, I; Rizzo, S.; Wynter, S; Alexandrov, O & Tong, C
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Water adsorption on O(2x2)/Ru(0001) from STM experiments andfirst-principles calculations

Description: We present a combined theoretical and experimental study of water adsorption on Ru(0001) pre-covered with 0.25 monolayers (ML) of oxygen forming a (2 x 2) structure. Several structures were analyzed by means of Density Functional Theory calculations for which STM simulations were performed and compared with experimental data. Up to 0.25 monolayers the molecules bind to the exposed Ru atoms of the 2 x 2 unit cell via the lone pair orbitals. The molecular plane is almost parallel to the surface w… more
Date: October 15, 2007
Creator: Cabrera-Sanfelix, P.; Sanchez-Portal, D.; Mugarza, A.; Shimizu,T.K.; Salmeron, M. & Arnau, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Final Technical Report

Description: Most prokaryotes of interest to DOE are poorly understood. Even when full genomic sequences are available, the function of only a small number of gene products are clear. The critical question is how to best infer the most probable network architectures in cells that are poorly characterized. The project goal is to create a computational hypothesis testing (CHT) framework that combines large-scale dynamical simulation, a database of bioinformatics-derived probable interactions, and numerical pa… more
Date: October 15, 2008
Creator: Church, Bruce W
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Simulations of plasma confinement in an antihydrogen trap

Description: The three-dimensional particle-in-cell (3-D PIC) simulation code WARP is used to study positron confinement in antihydrogen traps. The magnetic geometry is close to that of a UC Berkeley experiment conducted, with electrons, as part of the ALPHA collaboration (W. Bertsche et al., AIP Conf. Proc. 796, 301 (2005)). In order to trap antihydrogen atoms, multipole magnetic fields are added to a conventional Malmberg-Penning trap. These multipole fields must be strong enough to confine the antihydrog… more
Date: October 15, 2007
Creator: Gomberoff, K.; Fajans, J.; Friedman, A.; Grote, D.; Vay, J. L. & Wurtele, J. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Shotgun Metaproteomics of the Human Distal Gut Microbiota

Description: The human gut contains a dense, complex and diverse microbial community, comprising the gut microbiome. Metagenomics has recently revealed the composition of genes in the gut microbiome, but provides no direct information about which genes are expressed or functioning. Therefore, our goal was to develop a novel approach to directly identify microbial proteins in fecal samples to gain information about the genes expressed and about key microbial functions in the human gut. We used a non-targeted… more
Date: October 15, 2008
Creator: VerBerkmoes, N. C.; Russell, A. L.; Shah, M.; Godzik, A.; Rosenquist, M.; Halfvarsson, J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Perspectives on distributed computing : thirty people, four user types, and the distributed computing user experience.

Description: This report summarizes the methodology and results of a user perspectives study conducted by the Community Driven Improvement of Globus Software (CDIGS) project. The purpose of the study was to document the work-related goals and challenges facing today's scientific technology users, to record their perspectives on Globus software and the distributed-computing ecosystem, and to provide recommendations to the Globus community based on the observations. Globus is a set of open source software com… more
Date: October 15, 2008
Creator: Childers, L.; Liming, L.; Foster, I.; Science, Mathematics and Computer & Chicago, Univ. of
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

PERC 2 High-End Computer System Performance: Scalable Science and Engineering

Description: During two years of SciDAC PERC-2, our activities had centered largely on development of new performance analysis techniques to enable efficient use on systems containing thousands or tens of thousands of processors. In addition, we continued our application engagement efforts and utilized our tools to study the performance of various SciDAC applications on a variety of HPC platforms.
Date: October 15, 2006
Creator: Reed, Daniel
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Six-week time series of eddy covariance CO2 flux at Mammoth Mountain, California: performance evaluation and role of meteorological forcing

Description: CO{sub 2} and heat fluxes were measured over a six-week period (09/08/2006 to 10/24/2006) by the eddy covariance (EC) technique at the Horseshoe Lake tree kill (HLTK), Mammoth Mountain, CA, a site with complex terrain and high, spatially heterogeneous CO{sub 2} emission rates. EC CO{sub 2} fluxes ranged from 218 to 3500 g m{sup -2} d{sup -1} (mean = 1346 g m{sup -2} d{sup -1}). Using footprint modeling, EC CO{sub 2} fluxes were compared to CO{sub 2} fluxes measured by the chamber method on a gr… more
Date: October 15, 2007
Creator: Lewicki, Jennifer; Lewicki, J. L.; Fischer, M. L. & Hilley, G. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Toward a more robust variance-based global sensitivity analysis of model outputs

Description: Global sensitivity analysis (GSA) measures the variation of a model output as a function of the variations of the model inputs given their ranges. In this paper we consider variance-based GSA methods that do not rely on certain assumptions about the model structure such as linearity or monotonicity. These variance-based methods decompose the output variance into terms of increasing dimensionality called 'sensitivity indices', first introduced by Sobol' [25]. Sobol' developed a method of estimat… more
Date: October 15, 2007
Creator: Tong, C
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Simple Models and Methods for Estimating the UltrasonicReflectivity of Spot Welds

Description: This paper describes models and methods for estimating theacoustic reflectivity of the welded interfaces between spot-welded sheetsfrom normal-incidence pulse-echo ultrasound signals. The simple geometryof the problem allows an abstraction that does not resort to complex waveequations. Instead, a reflectivity model predicts the timing andamplitude of the echoes arriving at the probe. This reflectivity model isnested in a signal processing model; recovering reflectivity firstrequires deconvoluti… more
Date: October 15, 2006
Creator: Davis, William B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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