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DSP-Based dual-polarity mass spectrum pattern recognition for bio-detection

Description: The Bio-Aerosol Mass Spectrometry (BAMS) instrument analyzes single aerosol particles using a dual-polarity time-of-flight mass spectrometer recording simultaneously spectra of thirty to a hundred thousand points on each polarity. We describe here a real-time pattern recognition algorithm developed at Lawrence Livermore National Laboratory that has been implemented on a nine Digital Signal Processor (DSP) system from Signatec Incorporated. The algorithm first preprocesses independently the raw … more
Date: April 21, 2006
Creator: Riot, V; Coffee, K; Gard, E; Fergenson, D; Ramani, S & Steele, P
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Use of molecular modeling to determine the interaction and competition of gases within coal for carbon dioxide sequestration, Annual Technical Progress Report: 2005

Description: Molecular modeling was employed to both visualize and probe our understanding of carbon dioxide sequestration within a bituminous coal. A large-scale (>20,000 atoms) 3D molecular representation of Pocahontas No. 3 coal was generated. This model was constructed based on a the review data of Stock and Muntean, oxidation and decarboxylation data for aromatic clustersize frequency of Stock and Obeng, and the combination of Laser Desorption Mass Spectrometry data with HRTEM, enabled the inclusion… more
Date: April 21, 2006
Creator: Evanseck, Jeffrey D.; Madura, Jeffry D. & Mathews, Jonathan P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A Novel Approach to Mineral Carbonation: Enhancing Carbonation While Avoiding Mineral Pretreatment Process Cost

Description: Known fossil fuel reserves, especially coal, can support global energy demands for centuries to come, if the environmental problems associated with CO{sub 2} emissions can be overcome. Unlike other CO{sub 2} sequestration candidate technologies that propose long-term storage, mineral sequestration provides permanent disposal by forming geologically stable mineral carbonates. Carbonation of the widely occurring mineral olivine (e.g., forsterite, Mg{sub 2}SiO{sub 4}) is a large-scale sequestratio… more
Date: June 21, 2007
Creator: Chizmeshya, Andrew V. G.; McKelvy, Michael J.; Squires, Kyle; Carpenter, Ray W. & Bearat, Hamdallah
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Hydrothermal pretreatment of coal

Description: We have examined changes in Argonne Premium samples of Wyodak coal following 30 min treatment in liquid water at autogenous pressures at 150{degrees}, 250{degrees}, and 350{degrees}C. In most runs the coal was initially dried at 60{degrees}C/1 torr/20 hr. The changes were monitored by pyrolysis field ionization mass spectrometry (py-FIMS) operating at 2.5{degrees}C/min from ambient to 500{degrees}C. We recorded the volatility patterns of the coal tars evolved over that temperature range, and in… more
Date: December 21, 1989
Creator: Ross, David S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Summary of Blast Shield and Material Testing for Development of Solid Debris Collection at the National Ignition Facility (NIF)

Description: The ability to collect solid debris from the target chamber following a NIF shot has application for both capsule diagnostics, particularly for fuel-ablator mix, and measuring cross sections relevant to the Stockpile Stewardship program and nuclear astrophysics. Simulations have shown that doping the capsule with up to 10{sup 15} atoms of an impurity not otherwise found in the capsule does not affect its performance. The dopant is an element that will undergo nuclear activations during the NIF … more
Date: November 21, 2011
Creator: Shaughnessy, D A; Gostic, J M; Moody, K J; Grant, P M; Lewis, L A & Hutcheon, I D
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

EVALUATION OF TGA AS A QUALITY ASSURANCE TOOL FOR SURFACEMODIFIED ZIRCOLOY-4

Description: Thermogravimetric analysis (TGA) and coupled Mass Spectroscopy (MS) were evaluated to determine their suitability as a quality assurance tool for surface modified nickel plated zircaloy-4 liner tubes. Samples with 0, 0.1, 0.2, 0.3, and 0.4 mils of heat treated nickel plate were tested at 330, 370, and 400 C. Not all of the samples exhibited the expected typical parabolic shaped oxidation curve. The measured weight change was consistent for the as received and 0.2 mil and the 0.4 mil surface mod… more
Date: September 21, 2009
Creator: Korinko, P. & Imrich, K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Energy and Environment Directorate Status Report March 2006

Description: The Energy and Environment Directorate (E& ED) is one of 13 directorates at Lawrence Livermore National Laboratory (LLNL), which is operated by the University of California (UC) for the U.S. Department of Energy's National Nuclear Security Administration (NNSA). We operate in the context of a national security laboratory and focus on meeting major national needs, especially from a long-term perspective. In the LLNL context, E&ED is a hybrid ''program'' and ''discipline'' directorate, combin… more
Date: February 21, 2006
Creator: Long, J. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Evaluation of an Oxide Layer on NI-CR-MO-W Alloy Using Electrochemical Impedance Spectroscopy and Surface Analysis

Description: High corrosion resistance under very aggressive conditions is a distinguishing property of Ni-Cr-Mo-W alloys. One such alloy, Alloy 22, is a candidate material for fabrication of the outer layer of high-level nuclear waste (HLNW) packages for the proposed HLNW repository at Yucca Mountain, Nevada, USA. We are using Electrochemical Impedance Spectroscopy (EIS), ex-situ X-Ray Photoelectron Spectroscopy (XPS) and Time of Flight Secondary Ion Mass Spectroscopy (ToF SIMS) to characterize the electro… more
Date: December 21, 2006
Creator: Zagidulin, Dmitrij; Jakupi, Pellumb; Noel, James J. & Shoesmith, David W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Three methods to measure RH bond energies

Description: In this paper the authors compare and contrast three powerful methods for experimentally measuring bond energies in polyatomic molecules. The methods are: radical kinetics; gas phase acidity cycles; and photoionization mass spectroscopy. The knowledge of the values of bond energies are a basic piece of information to a chemist. Chemical reactions involve the making and breaking of chemical bonds. It has been shown that comparable bonds in polyatomic molecules, compared to the same bonds in radi… more
Date: March 21, 1993
Creator: Berkowitz, J.; Ellison, G. B. & Gutman, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Hydrothermal Pretreatment of Coal. Quarterly Report No. 1, September 21--December 15, 1989

Description: We have examined changes in Argonne Premium samples of Wyodak coal following 30 min treatment in liquid water at autogenous pressures at 150{degrees}, 250{degrees}, and 350{degrees}C. In most runs the coal was initially dried at 60{degrees}C/1 torr/20 hr. The changes were monitored by pyrolysis field ionization mass spectrometry (py-FIMS) operating at 2.5{degrees}C/min from ambient to 500{degrees}C. We recorded the volatility patterns of the coal tars evolved over that temperature range, and in… more
Date: December 21, 1989
Creator: Ross, David S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

PHOTOEMISSION AND SECONDARY ION MASS SPECTROMETRY STUDY OF URANIUM PASSIVATION BY C+ IMPLANTATION

Description: Preventing the corrosion and oxidation of uranium is important to the continued development of advanced nuclear fuel technologies. Knowledge of the surface reactions of uranium metal with various environmental and atmospheric agents, and the subsequent degradation processes, are vitally important in 21st century nuclear technology. A review of the oxidation of actinide elements and their use in catalysis summarizes the present understanding of the kinetics and mechanisms of the reaction in dry … more
Date: April 21, 2005
Creator: Nelson, A J; Felter, T E; Wu, K J; Evans, C; Ferreira, J L; Siekhaus, W J et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Semiconductor grade, solar silicon purification project. Technical quarterly report No. 8, 1 October 1977--31 December 1977. Motorola report No. 2257/8

Description: The technical progress reported in the current quarterly report can be divided into five task areas. They are as follows: (1) Spectroscopic Analysis and Characterization of the (SiF/sub 2/)/sub x/ Polymer and Si/sub x/F/sub y/ Homologues. Preliminary analysis utilizing N.M.R., T.G.A., D.S.C. and Mass Spec. are consistent with both the (SiF/sub 2/)/sub x/ polymer and Si/sub x/F/sub y/ homologues being nearly identical in chemical composition (mainly SiF/sub 2/ group in long chain polymers or cyc… more
Date: December 21, 1977
Creator: Ingle, William M.; Chaney, Robert; Thompson, Stephen; Rosler, Dick & Jackson, John
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Analysis of hazardous biological material by MALDI mass spectrometry

Description: Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-MS) has become a valuable tool for analyzing microorganisms. The speed with which data can be obtained from MALDI-MS makes this a potentially important tool for biological health hazard monitoring and forensic applications. The excitement in the mass spectrometry community in this potential field of application is evident by the expanding list of research laboratories pursuing development of MALDI-MS for bacteri… more
Date: March 21, 2000
Creator: Wahl, K. L.; Jarman, K. H.; Valentine, N. B.; Kingsley, M. T.; Petersen, C. E.; Cebula, S. T. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Measurement Techniques in Dry-Powdered Processing of Spent Nuclear Fuels

Description: High-performance liquid chromatography (HPLC) with inductively coupled plasma mass spectrometry (ICPMS) detection, {alpha}-spectrometry ({alpha}-S), and {gamma}-spectrometry ({gamma}-S) were used for the determination of nuclide content in five samples excised from a high-burnup fuel rod taken from a pressurized water reactor (PWR). The samples were prepared for analysis by dissolution of dry-powdered samples. The measurement techniques required no separation of the plutonium, uranium, and fiss… more
Date: July 21, 1999
Creator: Bowers, Delbert L.; Hong, Jon-Sook; Kim, Ho-Dong; Persiani, Paul J. & Wolf, Stephen F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Molecular Characterization of the Role of a Calcium Channel in Plant Development

Description: A stimulus-induced change in cellular Ca2+ levels is a critical component of energy transduction in plant and animal development. Demonstrating Ca2+'s involvement in any developmental process requires identification of mechanisms that regulate these Ca2+ changes. In plants, biochemical studies have implicated the activity of Ca2+ channels in increases in cellular Ca2+ levels; however, molecular evidence for these transporters is lacking. Our studies used the mosses Physcomitrella patens and Fun… more
Date: December 21, 2004
Creator: Schumaker, Karen S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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