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Rapid Ultrasensitive Chemical-Fingerprint Detection of Chemical and Biochemical Warfare Agents

Description: Vibrational spectra can serve as chemical fingerprints for positive identification of chemical and biological warfare molecules. The required speed and sensitivity might be achieved with surface-enhanced Raman spectroscopy (SERS) using nanotextured metal surfaces. Systematic and reproducible methods for preparing metallic surfaces that maximize sensitivity have not been previously developed. This work sought to develop methods for forming high-efficiency metallic nanostructures that can be inte… more
Date: December 1, 2002
Creator: ASHBY, CAROL I.; SHEPODD, TIMOTHY J.; YELTON, WILLIAM G. & MURON, DAVID J.
Partner: UNT Libraries Government Documents Department
open access

ELECTRICAL SUBSTATION RELIABILITY EVALUATION WITH EMPHASIS ON EVOLVING INTERDEPENDENCE ON COMMUNICATION INFRASTRUCTURE.

Description: The objective of this study is to develop a methodology for a probabilistic assessment of the reliability and security of electrical energy distribution networks. This includes consideration of the future grid system, which will rely heavily on the existing digitally based communication infrastructure for monitoring and protection. Another important objective of this study is to provide information and insights from this research to Consolidated Edison Company (Con Edison) that could be useful … more
Date: January 15, 2004
Creator: AZARM,M. A. BARI,R. A. MUSICKI,Z.
Partner: UNT Libraries Government Documents Department
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J/{psi} production in p{anti p} collisions at {radical}s = 1.8 TeV

Description: The authors have studied J/{psi} production in p{anti p} collisions at {radical}s = 1.8 TeV with the D0 detector at Fermilab, using a {mu}{sup +}{mu}{sup {minus}} data sample corresponding to an integrated luminosity of 13 pb{sup {minus}1}. They have measured the inclusive J/{psi} production cross section as a function of J/{psi} transverse momentum p{sub T}. For the kinematic range p{sub T} > 8 GeV/c and {vert_bar}{eta}{vert_bar} < 0.6 they obtain Br(J/{psi} {yields} {mu}{sup +}{mu}{sup {minus… more
Date: July 1, 1995
Creator: Abachi, S.
Partner: UNT Libraries Government Documents Department
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Searches for new gauge bosons using the D0 detector

Description: We present the results of searches for additional gauge bosons beyond the W and Z bosons using the 1992-1993 Tevatron data set collected with the D0 detector. The signatures studied are W{prime} {yields} e{nu}, W{prime} {yields} {tau}{nu} with {tau} {yields} e{nu}{bar {nu}}, assuming stable neutrinos; W{sub R} {yields} e + X and W{sub R} {yields} eejj, assuming massive neutrinos; and Z{prime} {yields} ee. Lower limits on the W{prime} mass and Z{prime} mass at the 95% confidence level, and the m… more
Date: July 1, 1995
Creator: Abachi, S.; Abbott, B. & Abolins, M.
Partner: UNT Libraries Government Documents Department
open access

Search for wrong sign D/sup 0/ decays with the HRS detector

Description: Using a data sample corresponding to an integrated luminosity of 300pb/sup -1/ obtained at PEP with the HRS detector we have searched for the wrong sign decay of D/sup 0/ mesons in the decays D* ..-->.. D/sup 0/..pi... We obtain a 90% confidence level limit of 4.0% on the ratio of the wrong sign to the right sign decay rate in the K..pi.. mode. This is the best model independent limit on mixing currently available and constrains the nature of the wrong sign signal recently reported by the MARK … more
Date: 1986
Creator: Abachi, S.; Akerlof, C.; Barringer, P.; Blockus, D.; Brabson, B.; Brom, J. M. et al.
Partner: UNT Libraries Government Documents Department
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Theoretical Atomic Physics code development IV: LINES, A code for computing atomic line spectra

Description: A new computer program, LINES, has been developed for simulating atomic line emission and absorption spectra using the accurate fine structure energy levels and transition strengths calculated by the (CATS) Cowan Atomic Structure code. Population distributions for the ion stages are obtained in LINES by using the Local Thermodynamic Equilibrium (LTE) model. LINES is also useful for displaying the pertinent atomic data generated by CATS. This report describes the use of LINES. Both CATS and LINE… more
Date: December 1, 1988
Creator: Abdallah, J. Jr. & Clark, R.E.H.
Partner: UNT Libraries Government Documents Department
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The calculation of satellite line structures in highly stripped plasmas

Description: This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Recently developed high-resolution x-ray spectrographs have made it possible to measure satellite structures from various plasma sources with great detail. These lines are weak optically thin lines caused by the decay of dielectronic states and generally accompany the resonance lines of H-like and He-like ions. The Los Alamos atomic physics and kine… more
Date: November 1, 1998
Creator: Abdallah, J. Jr.; Kilcrease, D. P.; Faenov, A. Ya. & Pikuz, T. A.
Partner: UNT Libraries Government Documents Department
open access

Noncontact surface thermometry for microsystems: LDRD final report.

Description: We describe a Laboratory Directed Research and Development (LDRD) effort to develop and apply laser-based thermometry diagnostics for obtaining spatially resolved temperature maps on working microelectromechanical systems (MEMS). The goal of the effort was to cultivate diagnostic approaches that could adequately resolve the extremely fine MEMS device features, required no modifications to MEMS device design, and which did not perturb the delicate operation of these extremely small devices. Two … more
Date: October 1, 2006
Creator: Abel, Mark (Georgia Institute of Technology, Atlanta, GA); Beecham, Thomas (Georgia Institute of Technology, Atlanta, GA); Graham, Samuel (Georgia Institute of Technology, Atlanta, GA); Kearney, Sean Patrick; Serrano, Justin Raymond & Phinney, Leslie Mary
Partner: UNT Libraries Government Documents Department
open access

The role of catalyst precursor anions in coal gasification. Fifth quarterly report

Description: The aims of the proposed project are to enrich our understanding of the roles of various aqueous soluble catalyst precursor anions on the surface electrical properties of coal and to ascertain the influence of the surface charge on the adsorption, dispersion, and activities of calcium and potassium. These goals will be achieved by impregnating a demineralized North Dakota lignite (PSOC 1482) with calcium or potassium catalyst precursors containing acetate (CH{sub 3}COO{sup {minus}}), chloride (… more
Date: April 1, 1993
Creator: Abotsi, G. M. K.
Partner: UNT Libraries Government Documents Department
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The role of catalyst precursor anions in coal gasification. Seventh quarterly report, April--June 1993

Description: This project investigates the roles of various aqueous soluble catalyst precursor anions, specifically acetate (CH{sub 3}COO{sup {minus}}), chloride (Cl{sup {minus}}), nitrate (NO{sub 3}{sup {minus}}), sulfate (SO{sub 4}{sup 2{minus}}) and carbonate (CO{sub 3}{sup 2{minus}}) anions on the surface electrical properties of coal and seeks to understand the effects of these anions on the adsorption, dispersion and activities of calcium and potassium. In order to investigate the effects of lower ani… more
Date: September 1, 1993
Creator: Abotsi, G. M. K.
Partner: UNT Libraries Government Documents Department
open access

Study of heavy quark production with the Mark II at PEP

Description: The methods adopted by the Mark II collaboration to study heavy quark production at PEP are described. Two complementary techniques are used: D* tagging using the decay chain D*/sup +/. D/sup 0/..pi../sup +/, D/sup 0/ ..-->.. K/sup -/..pi../sup +/, and inclusive lepton tagging using the characteristic p/sub T/ distributions to distinguish contributions from b and c quarks. These techniques are used to derive information about heavy quark fragmentation and about the weak coupling of heavy quarks. more
Date: October 1, 1983
Creator: Abrams, G.; Amidei, D.; Baden, A.; de la Vaissiere, C.; Gidal, G.; Gold, M. et al.
Partner: UNT Libraries Government Documents Department
open access

Discovery of Very High Energy Gamma Rays from PKS 1424+240 and Multiwavelength Constraints on its Redshift

Description: We report the first detection of very-high-energy (VHE) gamma-ray emission above 140GeV from PKS 1424+240, a BL Lac object with an unknown redshift. The photon spectrum above 140GeV measured by VERITAS is well described by a power law with a photon index of 3.8 {+-}0.5{sub stat} {+-} 0.3{sub syst} and a flux normalization at 200 GeV of (5.1 {+-} 0.9{sub stat} {+-} 0.5{sub syst}) x 10{sup -11} TeV{sup -1} cm{sup -2} s{sup -1}, where stat and syst denote the statistical and systematical uncertain… more
Date: April 5, 2012
Creator: Acciari, V. A.; Aliu, E.; Arlen, T.; Aune, T.; Bautista, M.; Beilicke, M. et al.
Partner: UNT Libraries Government Documents Department
open access

Salicylic Acid as a Reagent for the Spectrophotometric Determination of Beryllium

Description: 1. The reaction between beryllium salts and salicylic acid was studied by the spectrophotometric method in the ultra violet portion of the spectrum. The optimum pH value for this process was found to be 9.0 to 9.5. 2. Two independent methods showed that beryllium and salicylic acid form a compound in the ration 1:2. The instability constant was determined for the a complex of the formula (Be OH Sal2)3- names (4.9 +- 0.6) x 10-18. 3. The stability of the complex and the availability of the reag… more
Date: 1961
Creator: Adamovich, L. P. & de Bruin, H. J.
Partner: UNT Libraries Government Documents Department
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Theoretical light and velocity curves for Cepheid variables. [Nonlinear models]

Description: New Research Initiatives Program W-318 was successfully completed with the calculation of a series of nonlinear Cepheid models with the new DYN code. The dynamical zoning feature of the DYN code makes it unique in that it allows reliable light curves, as well as velocity curves, to be calculated. The models are used to extend to light curves Christy's conclusion, based on velocity curves, that the observations of Cepheids cannot be matched unless the mass is significantly reduced (assuming a ho… more
Date: December 1, 1978
Creator: Adams, T. F.; Davis, C. G. & Keller, C. F.
Partner: UNT Libraries Government Documents Department
open access

Energy Spectrum of Neutrons from 3-10 MEV

Description: The energy distributions of neutrons in the 3-10 Mev energy range resulting from the bombardment of thin U targets are being investigated by the measurement of proton recoils in photographic plates.
Date: February 11, 1952
Creator: Adelman, Frank
Partner: UNT Libraries Government Documents Department
open access

Experimental Cesium Line Shapes

Description: In partially-ionized cesium plasmas above 10/sup 13/ ionscm/sup -3/, the plasma-broadened lines are easily measured and can be used as a simple diagnostic method for the determination of ion density, once the width versus ion density relationship is established either theoretically or experimentally. Measured line widths are presented and results are compared with theoretical widths. The profiles of various lines of the sharp, diffuse, and fundamental series lines of cesium were measured at kno… more
Date: January 1, 1962
Creator: Agnew, L. & Summers, C.
Partner: UNT Libraries Government Documents Department
open access

Report to users of Atlas

Description: This report contains the following topics: Status of the ATLAS Accelerator; Highlights of Recent Research at ATLAS; Program Advisory Committee; ATLAS User Group Executive Committee; FMA Information Available On The World Wide Web; Conference on Nuclear Structure at the Limits; and Workshop on Experiments with Gammasphere at ATLAS.
Date: June 1, 1996
Creator: Ahmad, I. & Glagola, B.
Partner: UNT Libraries Government Documents Department
open access

Characterization of gas-aerosol interaction kinetics using morphology dependent stimulated Raman scattering

Description: A research program on the influence of aerosol surface structure on the kinetics of gas-aerosol interactions is proposed. The experiments involve measuring changes in gas phase chemical reaction rates as a function of exposure to a specific aerosol. Aerosols with differing surface properties will be generated by changing the composition and/or temperature of the material making up the aerosol. Kinetic data generated can be used directly in atmospheric modelling calculations. The surface structu… more
Date: January 1, 1992
Creator: Aker, P. M.
Partner: UNT Libraries Government Documents Department
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Characterization of gas-aerosol interaction kinetics using morphology dependent stimulated Raman scattering. Final technical report

Description: A research program on the influence of aerosol surface structure on the kinetics of gas-aerosol interactions is proposed. The experiments involve measuring changes in gas phase chemical reaction rates as a function of exposure to a specific aerosol. Aerosols with differing surface properties will be generated by changing the composition and/or temperature of the material making up the aerosol. Kinetic data generated can be used directly in atmospheric modelling calculations. The surface structu… more
Date: December 31, 1992
Creator: Aker, P. M.
Partner: UNT Libraries Government Documents Department
open access

Optical Imaging in Microstructures

Description: This research was focused on developing morphology-dependent stimulated raman scattering (MDSRS) spectroscopy as an analytic optical imaging technique. MDSRS uses the cavity modes (called morphology dependent resonances, MDRs) associated with axisymmetric dielectric microstructures to generate nonlinear optical signals. Since different cavity modes span different regions inside the microstructure, it becomes possible to generate location-specific spectra. The information gotten from MDSRS imagi… more
Date: April 11, 2001
Creator: Aker, P. M.
Partner: UNT Libraries Government Documents Department
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