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In-situ spectro-microscopy on organic films: Mn-Phthalocyanine on Ag(100)

Description: Metal phthalocyanines are attracting significant attention, owing to their potential for applications in chemical sensors, solar cells and organic magnets. As the electronic properties of molecular films are determined by their crystallinity and molecular packing, the optimization of film quality is important for improving the performance of organic devices. Here, we present the results of in situ low-energy electron microscopy / photoemission electron microscopy (LEEM/PEEM) studies of incorporation-limited growth [1] of manganese-phthalocyanine (MnPc) on Ag(100) surfaces. MnPc thin films were grown on both, bulk Ag(100) surface and thin Ag(100)/Fe(100) films, where substrate spin-polarized electronic states can be modified through tuning the thickness of the Ag film [2]. We also discuss the electronic structure and magnetic ordering in MnPc thin films, investigated by angle- and spin-resolved photoemission spectroscopy.
Date: August 18, 2013
Creator: A., Al-Mahboob; Vescovo, E. & Sadowski, J.T.
Partner: UNT Libraries Government Documents Department
open access

INTERIM REPORT--INDEPENDENT VERIFICATION SURVEY OF SECTION 3, SURVEY UNITS 1, 4 AND 5 EXCAVATED SURFACES, WHITTAKER CORPORATION, REYNOLDS INDUSTRIAL PARK, TRANSFER, PENNSYLVANIA DCN: 5002-SR-04-0"

Description: At Pennsylvania Department of Environmental Protection's request, ORAU's IEAV program conducted verification surveys on the excavated surfaces of Section 3, SUs 1, 4, and 5 at the Whittaker site on March 13 and 14, 2013. The survey activities included visual inspections, gamma radiation surface scans, gamma activity measurements, and soil sampling activities. Verification activities also included the review and assessment of the licensee�s project documentation and methodologies. Surface scans identified four areas of elevated direct gamma radiation distinguishable from background; one area within SUs 1 and 4 and two areas within SU5. One area within SU5 was remediated by removing a golf ball size piece of slag while ORAU staff was onsite. With the exception of the golf ball size piece of slag within SU5, a review of the ESL Section 3 EXS data packages for SUs 1, 4, and 5 indicated that these locations of elevated gamma radiation were also identified by the ESL gamma scans and that ESL personnel performed additional investigations and soil sampling within these areas. The investigative results indicated that the areas met the release criteria.
Date: April 18, 2013
Creator: ADAMS, WADE C
Partner: UNT Libraries Government Documents Department
open access

Motion Planning for a Direct Metal Deposition Rapid Prototyping System

Description: A motion planning strategy was developed and implemented to generate motion control instructions from solid model data for controlling a robotically driven solid free-form fabrication process. The planning strategy was tested using a PUMA type robot arm integrated into a LENS{trademark} (Laser Engineered Net Shape) system. Previous systems relied on a series of x, y, and z stages, to provide a minimal coordinated motion control capability. This limited the complexity of geometries that could be constructed. With the coordinated motion provided by a robotic arm, the system can produce three dimensional parts by ''writing'' material onto any face of existing material. The motion planning strategy relied on solid model geometry evaluation and exploited robotic positioning flexibility to allow the construction of geometrically complex parts. The integration of the robotic manipulator into the LENS{trademark} system was tested by producing metal parts directly from CAD models.
Date: October 18, 1999
Creator: AMES,ARLO L.; HENSINGER,DAVID M. & KUHLMANN,JOEL L.
Partner: UNT Libraries Government Documents Department
open access

Study of electron and neutrino interactions

Description: This is the final report for the DOE-sponsored experimental particle physics program at Virginia Tech to study the properties of the Standard Model of strong and electroweak interactions. This contract (DE-AS05-80ER10713) covers the period from August 1, 1980 to January 31, 1993. Task B of this contract, headed by Professor Alexander Abashian, is described in this final report. This program has been pursued on many fronts by the researchers-in a search for axions at SLAC, in electron-positron collisions in the AMY experiment at the TRISTAN collider in Japan, in measurements of muon decay properties in the MEGA and RHO experiments at the LAMPF accelerator, in a detailed analysis of scattering effects in the purported observation of a 17 keV neutrino at Oxford, in a search for a disoriented chiral condensate with the MiniMax experiment at Fermilab, and in an R&D program on resistive plate counters that could find use in low-cost high-quality charged particle detection at low rates.
Date: March 18, 1997
Creator: Abashian, A.
Partner: UNT Libraries Government Documents Department
open access

Study of electron and neutrino interactions. Final report

Description: This is the final report for the DOE-sponsored experimental particle physics program at Virginia Tech to study the properties of the Standard Model of strong and electroweak interactions. This contract (DE-AS05-80ER10713) covers the period from August 1, 1980 to January 31, 1993. Task B of this contract, headed by Professor Alexander Abashian, is described in this final report. This program has been pursued on many fronts by the researchers in a search for axions at SLAC, in electron-positron collisions in the AMY experiment at the TRISTAN collider in Japan, in measurements of muon decay properties in the MEGA and RHO experiments at the LAMPF accelerator, in a detailed analysis of scattering effects in the purported observation of a 17 keV neutrino at Oxford, in a search for a disoriented chiral condensate with the MiniMax experiment at Fermilab, and in an R&D program on resistive plate counters that could find use in low-cost high-quality charged particle detection at low rates.
Date: March 18, 1997
Creator: Abashian, A.
Partner: UNT Libraries Government Documents Department
open access

Measurements Through a Hot Cell Window Using Optical Tooling

Description: S>Optical tooling has been evaluated for the measurement of physical dimensions of radioactive parts through hot cell windows. Instruments were set up outside of a four foot thick lead glass window and by means of a grid plate which had been accurately scribed, a ''contour map'' or calibration chart of the window variations was recorded. Although the window was not specially selected, the readings were within 1.0% of the true dimension without using correction factors. One of the calibration chart with the window reduced the error to plus or minus 0.1%. The method is considered feasible and sufficiently fast for a wide variety of hot cell measurements. A pin point light source is suggested as a simple check for selective assembly of lead glass laminates during manufacture of hot cell windows to provide control of optical properties. (auth)
Date: July 18, 1958
Creator: Abbatiello, A. A.
Partner: UNT Libraries Government Documents Department
open access

Deuteron photodisintegration : new results from TJNAF.

Description: The first measurements of the differential cross section from d({gamma},p)n up to 4.0 GeV were performed at the Thomas Jefferson National Accelerator Facility (TJNAF, formerly CEBAF). Bremsstrahlung photons from electron beam impinging on a copper radiator and a liquid deuterium target were employed for this experiment. The experiment was performed in Hall C where the photoprotons at forward angles in the center-of-mass were detected in the High Momentum Spectrometer (HMS) and photoprotons at backward angles were detected in the Short Orbit Spectrometer (SOS). The bremsstrahlung photon energy was reconstructed from the measured proton momentum and angle using the two-body kinematics. We report the cross section results at the proton center-of-mass angles of 37{degree} and 90{degree}. These results are in good agreement with previous lower energy measurements. The 90{degree} data continue to show the constituent-counting-rule behavior up to 4 GeV. The results will be compared with models based on QCD as well as those based on meson-exchange theory.
Date: November 18, 1997
Creator: Abbott, D. J.; Ahmidouch, A.; Armstrong, C. S.; Arrington, J.; Cummings, W. J.; Geesaman, D. F. et al.
Partner: UNT Libraries Government Documents Department
open access

Reductive Precipitation of Metals Photosensitized by Tin Protoporphyrin

Description: For the first time, we show that redox-sensitive metals, which are highly soluble in the oxidized state can be reduced and precipitated from aqueous solution using tin protoporphyrin and light in the presence of an electron donor. Hg{sup 2+} and Cu{sup 2+} were reduced to the metallic state, and Ub{sup 6+} precipitated as oxide with very low volubility, suggesting that removal of these metals via reductive photoreduction and precipitation may be an innovative way for wastewater treatment. Ag{sup 2+} and Au{sup 2+} were reduced to the metallic state and precipitated as nanoparticles. Finally, using tin porphyrins and light for a variety of purposes involving reactions that require a low redox potential may be a good step toward energy conservation and environmentally benign processing.
Date: January 18, 2000
Creator: Abdelouas, A.; Gong, W. L. & Shelnutt, John A.
Partner: UNT Libraries Government Documents Department
open access

Reduction of Heavy Metals by Cytochrome c(3)

Description: We report on reduction and precipitation of Se(VI), Pb(II), CU(II), U(VI), Mo(VI), and Cr(VI) in water by cytochrome c{sub 3} isolated from Desulfomicrobium baczdatum [strain 9974]. The tetraheme protein cytochrome c{sub 3} was reduced by sodium dithionite. Redox reactions were monitored by UV-visible spectroscopy of cytochrome c{sub 3}. Analytical electron microscopy work showed that Se(VI), Pb(II), and CU(II) were reduced to the metallic state, U(W) and Mo(W) to U(IV) and Mo(IV), respectively, and Cr(VI) probably to Cr(III). U(IV) and Mo(W) precipitated as oxides and Cr(III) as an amorphous hydroxide. Cytochrome c{sub 3} was used repeatedly in the same solution without loosing its effectiveness. The results suggest usage of cytochrome c{sub 3} to develop innovative and environmentally benign methods to remove heavy metals from waste- and groundwater.
Date: January 18, 2000
Creator: Abdelouas, A.; Gong, W. L.; Lutze, W.; Nuttall, E. H.; Sprague, F.; Shelnutt, John A. et al.
Partner: UNT Libraries Government Documents Department
open access

Final Pantex Report - 2006 [Phase 1 plan for assessment of Former Workers at the Pantex Facility]

Description: The purpose of this project was to develop a Phase 1 plan for assessment of Former Workers at the Pantex Facility in Amarillo, TX and to determine the suitability to start a medical surveillance program among former workers for this site.
Date: July 18, 2013
Creator: Abdo, Ronna
Partner: UNT Libraries Government Documents Department
open access

Simulation Data as Data Streams

Description: Computational or scientific simulations are increasingly being applied to solve a variety of scientific problems. Domains such as astrophysics, engineering, chemistry, biology, and environmental studies are benefiting from this important capability. Simulations, however, produce enormous amounts of data that need to be analyzed and understood. In this overview paper, we describe scientific simulation data, its characteristics, and the way scientists generate and use the data. We then compare and contrast simulation data to data streams. Finally, we describe our approach to analyzing simulation data, present the AQSim (Ad-hoc Queries for Simulation data) system, and discuss some of the challenges that result from handling this kind of data.
Date: November 18, 2003
Creator: Abdulla, G; Arrighi, W & Critchlow, T
Partner: UNT Libraries Government Documents Department
open access

Electric Utility Provisions in House-Passed H.R. 6, 109th Congress

Description: This report describes Title XII of the House-passed H.R. 6 in the 109th Congress and other sections that deal with electric power issues. In part, Title XII would create an electric reliability organization (ERO) that would enforce mandatory reliability standards for the bulk-power system. All ERO standards would be approved by the Federal Energy Regulatory Commission (FERC). Under this title, the ERO could impose penalties on a user, owner, or operator of the bulk-power system that violates any FERC-approved reliability standard.
Date: August 18, 2005
Creator: Abel, Amy
Partner: UNT Libraries Government Documents Department
open access

[Letter from Julie Anne Abel to Phillip C. Diebel, March 18, 1997]

Description: A letter from Julie Anne Abel to Phillip C. Diebel about enclosing the final National Specialty Program grant payment to the North Texas Institute for Educators on the Visual Arts from The Getty Center for Education in the Arts. The payment is not attached to the document
Date: March 18, 1997
Creator: Abel, Julie Anne
Partner: UNT Libraries Special Collections
open access

Metal waste forms from treatment of EBR-II spent fuel.

Description: Demonstration of Argonne National Laboratory's electrometallurgical treatment of spent nuclear fuel is currently being conducted on irradiated, metallic driver fuel and blanket fuel elements from the Experimental Breeder Reactor-II (EBR-II) in Idaho. The residual metallic material from the electrometallurgical treatment process is consolidated into an ingot, the metal waste form (MWF), by employing an induction furnace in a hot cell. Scanning electron microscopy (SEM) and chemical analyses have been performed on irradiated cladding hulls from the driver fuel, and on samples from the alloy ingots. This paper presents the microstructures of the radioactive ingots and compares them with observations on simulated waste forms prepared using non-irradiated material. These simulated waste forms have the baseline composition of stainless steel - 15 wt % zirconium (SS-15Zr). Additions of noble metal elements, which serve as surrogates for fission products, and actinides are made to that baseline composition. The partitioning of noble metal and actinide elements into alloy phases and the role of zirconium for incorporating these elements is discussed in this paper.
Date: May 18, 1998
Creator: Abraham, D. P.
Partner: UNT Libraries Government Documents Department
open access

Solvation Descriptors for Ferrocene, and the Estimation of Some Physicochemical and Biochemical Properties

Description: Article on solvation descriptors for ferrocene, and the estimation of some physiochemical and biochemical properties.
Date: September 18, 2000
Creator: Abraham, M. H. (Michael H.); Benjellou-Dakhama, Nora; Gola, Joelle R. M.; Acree, William E. (William Eugene); Cain, William S. & Cometto-Muñiz, J. Enrique
Partner: UNT College of Arts and Sciences
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