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1,2-HOIQO--A highly versatile 1,2-HOPO analog

Description: A cyclic, bidentate hydroxamic acid binding unit based on an isoquinoline scaffold has been utilized for the synthesis of a hexadentate tripodal ligand based on the TREN backbone. This prototype for a new class of multidentate chelators forms mononuclear iron(III) complexes and one-dimensional coordination polymers with lanthanide(III) cations. The latter has been determined by single crystal X-ray analysis of the cerium species. The solid state structure in the monoclinic space group P2{sub 1}/c (C{sub 36}H{sub 34}CeN{sub 7}O{sub 11}, a = 12.341(2){angstrom}, b = 26.649(4){angstrom}, c = 10.621(2){angstrom}, {alpha} = {gamma} = 90{sup o}, {beta} = 96.753(3){sup o}, V = 3468.6(9) {angstrom}{sup 3}, Z = 4) exhibits a trigonal-dodecahedral environment around the cerium cation. The proof of concept for the versatility of the new scaffold has been shown by the modification of the crucial precursor 3-carboxyiso-coumarin through electrophilic aromatic substitutions to yield the corresponding chlorosulfonated and nitrated analogs.
Date: August 7, 2006
Creator: Seitz, Michael; Pluth, Michael D. & Raymond, Kenneth N.
Partner: UNT Libraries Government Documents Department

15 KJ FLASH LAMP, POWER CONDITIONING UNIT DESIGNED FOR SAFTY, RELIABILITY & MANUFACTURABILITY*

Description: A 15kJoule, Flash Lamp Power Conditioning Unit has been successfully designed, developed, and deployed in the National Ignition Facility (NIF) Preamplifier Modules (PAM). The primary design philosophy of this power conditioning unit (PCU) is safety, reliability, and manufacturability. Cost reduction over commercially equivalent systems was also achieved through an easily manufactured packaging design optimized to meet NIF requirements. While still maintaining low cost, the PCU design includes a robust control system, fault diagnostic system, and safety features. The pulsed power design includes 6 PFN modules, each including a dual series injection trigger transformer, that drive a total of 12 flash lamp loads. The lamps are individually triggered via a 20kV pulse produced by a 1kV, MCT switched capacitive discharge unit on the primary side of the trigger transformer. The remote control interface includes an embedded controller that captures flash lamp current wave forms and fault status for each shot. The embedded controller provides the flexibility of remotely adjusting both the main drive voltage from 1.6 to 2.5 kV and the trigger voltage from 0 to 20 kV.
Date: August 7, 2007
Creator: James, G; Merritt, B; Dreifuerst, G & Strickland, S
Partner: UNT Libraries Government Documents Department

340 Representative sampling verification tank sampling and analysis plan

Description: This Sampling and Analysis Plan contains requirements for characterizing the 340 vault tank 1. The objective of the sampling and characterization is to determine if the tank is homogeneous when agitated and which sampling method provides the most representative sample. A secondary objective is to collect and characterize solid samples.
Date: August 7, 1996
Creator: Olander, A.R., Westinghouse Hanford
Partner: UNT Libraries Government Documents Department

Absolute measurements of the high-frequency magnetic dynamics in high-{Tc} superconductors

Description: The authors review recent measurements of the high-frequency dynamic magnetic susceptibility in the high-T{sub c} superconducting systems La{sub 2{minus}x}Sr{sub x}CuO{sub 4} and YBa{sub 2}Cu{sub 3}O{sub 6+x}. Experiments were performed using the chopper spectrometers HET and MARI at the ISIS spallation source. The authors have placed their measurements on an absolute intensity scale, this allows systematic trends to be seen and comparisons with theory to be made. They find that the insulating S = 1/2 antiferromagnetic parent compounds show a dramatic renormalization in the spin wave intensity. The effect of doping on the response is to cause broadenings in wave vector and large redistributions of spectral weight in frequency.
Date: August 7, 1997
Creator: Hayden, S.M.; Aeppli, G.; Dai, P.; Mook, H.A.; Perring, T.G.; Cheong, S.W. et al.
Partner: UNT Libraries Government Documents Department

Accident analysis and safety review of DOE Category B reactors

Description: DOE is employing the principle of comparability with the NRC requirements to guide its safety program. Since the safety record of research reactors licensed by the NRC has been established and accepted, the comparison of DOE Orders applicable to DOE research reactors with the NRC regulations applicable to research reactors would identify strengths and weaknesses of the DOE Orders. The comparison was made in 14 general topics of safety which are labeled Areas of Safety Concerns. This paper focuses on the Area of accident analysis and safety review and presents recommendations in these areas. 12 refs.
Date: August 7, 1990
Creator: Kimura, C. Y.
Partner: UNT Libraries Government Documents Department

Accident investigation board report on the May 14, 1997, chemical explosion at the Plutonium Reclamation Facility, Hanford Site,Richland, Washington - summary report

Description: This report is a summary of the Accident Investigation Board Report on the May 14, 1997, Chemical Explosion at the Plutonium Reclamation Facility, Hanford Site, Richland, Washington (DOE/RL-97-59). The referenced report provides a greater level of detail and includes a complete discussion of the facts identified, analysis of those facts, conclusions derived from the analysis, identification of the accident`s causal factors, and recommendations that should be addressed through follow-up action by the U.S. Department of Energy and its contractors. This companion document provides a concise summary of that report, with emphasis on management issues. Evaluation of emergency and occupational health response to, and radiological and chemical releases from, this accident was not within the scope of this investigation, but is the subject of a separate investigation and report (see DOE/RL-97-62).
Date: August 7, 1997
Creator: Gerton, R.E.
Partner: UNT Libraries Government Documents Department

Advanced thermal barrier coating system development: Technical progress report

Description: Objectives are to provide an improved TBC system with increased temperature capability and improved reliability, for the Advanced Turbine Systems program (gas turbine). The base program consists of three phases: Phase I, program planning (complete); Phase II, development; and Phase III (selected specimen-bench test). Work is currently being performed in Phase II.
Date: August 7, 1996
Partner: UNT Libraries Government Documents Department

ADVANCES IN X-RAY COMPUTED MICROTOMOGRAPHY AT THE NSLS.

Description: The X-Ray Computed Microtomography workstation at beamline X27A at the NSLS has been utilized by scientists from a broad range of disciplines from industrial materials processing to environmental science. The most recent applications are presented here as well as a description of the facility that has evolved to accommodate a wide variety of materials and sample sizes. One of the most exciting new developments reported here resulted from a pursuit of faster reconstruction techniques. A Fast Filtered Back Transform (FFBT) reconstruction program has been developed and implemented, that is based on a refinement of the ''gridding'' algorithm first developed for use with radio astronomical data. This program has reduced the reconstruction time to 8.5 sec for a 929 x 929 pixel{sup 2} slice on an R10,000 CPU, more than 8x reduction compared with the Filtered Back-Projection method.
Date: August 7, 1998
Creator: DOWD,B.A.
Partner: UNT Libraries Government Documents Department

AMEC GEOMATRIX/ARA GROUNDWATER REMEDIAITON TRIP REPORT

Description: City of Rialto, Well No.3 Demonstration System Integration Project, and Baldwin Park Operable Unit, Baldwin Park, California. The groundwater remediation contractors are AMEC Geomatrix and ARA. The sites were visited on July 22, 2008. Fluor Hanford and the U.S. Department of Energy are currently looking at a variety of alternatives to capture carbon tetrachloride, nitrates, and other COCs from 200-ZP-l groundwater. A few of the more important objectives of our visits were to: (1) Evaluate the treatment systems being used by AMEC Geomatrix to address VOCs, perchlorate, NDMA, 1,4,-Dioxane, and 1,2,3 TCP in a drinking water source; (2) Evaluate how effective these treatment methods have been; (3) Determine the types of problems they have encountered with these treatment systems and how they addressed these problems; (4) Determine the types of secondary wastes being generated by the system; (5) Determine how clean of an operation these companies run; and (6) Determine if the site is worth being visited by DOE-RL at a later date.
Date: August 7, 2008
Creator: SA, SIMMONS
Partner: UNT Libraries Government Documents Department

America Competes Act: NIST Applied Some Safeguards in Obtaining Expert Services, but Additional Direction from Congress Is Needed

Description: A letter report issued by the Government Accountability Office with an abstract that begins "The America COMPETES Act gave the National Institute of Standards and Technology (NIST), within the Department of Commerce, the authority, through 2010, to obtain the temporary services of up to 200 experts or consultants per year, but did not specify how the agency should acquire these services. NIST has used this authority to award personal services contracts to obtain the services of individuals. The act requires GAO to report on whether additional safeguards would be needed if NIST's authority were to be made permanent. To meet that requirement, GAO determined (1) the extent to which NIST has used its authority; (2) how effective the authority has been in helping NIST meet its need for experts; and (3) the extent to which NIST has provided appropriate safeguards over its use, and what additional safeguards are needed. GAO reviewed statutes, regulations, federal guidance, and NIST's contracts. In addition, GAO interviewed officials at NIST, Commerce, and the Office of Personnel Management (OPM)."
Date: August 7, 2009
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

ANALYTICAL METHOD FOR MEASURING TOTAL PROTIUM AND TOTAL DEUTERIUM IN A GAS MIXTURE CONTAINING H2, D2,AND HD VIA GAS CHAROMATOGRAPHY

Description: The most common analytical method of identifying and quantifying non-radioactive isotopic species of hydrogen is mass spectrometry. A low mass, high resolution mass spectrometer with adequate sensitivity and stability to identify and quantify hydrogen isotopes in the low ppm range is an expensive, complex instrument. A new analytical technique has been developed that measures both total protium (H) and total deuterium (D) in a gas mixture containing H{sub 2}, D{sub 2}, and HD using an inexpensive micro gas chromatograph (GC) with two molecular sieve columns. One column uses D{sub 2} as the carrier gas and the other uses H{sub 2} as the carrier gas. Laboratory tests have shown that when used in this configuration the GC can measure both total protium and total deuterium each with a detection and quantification limit of less than 20 ppm.
Date: August 7, 2007
Creator: Sessions, H
Partner: UNT Libraries Government Documents Department

APD detector electronics for the NSTX Thomson scattering system

Description: An electronics system has been installed and tested for the readout of APD detectors for the NSTX Thomson scattering system. Similar to previous designs, it features preamps with a fast and a slow output. The fast output uses pulse shaping to optimize sensitivity for the 8 nsec scattered light pulse while rejecting noise in the intrinsic plasma background. A low readout noise of {approximately}25 photoelectrons is achieved at an APD gain of 75. The design incorporates a number of features to provide flexibility for various modes of calibration.
Date: August 7, 2000
Creator: Johnson, D.W.; LeBlanc, B.P.; Long, D.L. & Renda, G.
Partner: UNT Libraries Government Documents Department

Application of Reservoir Characterization and Advanced Technology to Improve Recovery and Economics in a Lower Quality Shallow Shelf Carbonate Reservoir, Class II

Description: The Oxy operated Class 2 Project at West Welch Project is designed to demonstrate how the use of advanced technology can improve the economics of miscible CO2 injection projects in lower quality Shallow Shelf Carbonate reservoirs. The research and design phase (Budget Period 1) primarily involved advanced reservoir demonstration characterization. The current demonstration phase (Budget Period 2) is the implementation of the reservoir management plan for an optimum miscible CO2 flood design based on the reservoir characterization.
Date: August 7, 2001
Creator: Hickman, T. Scott; Justice, James J. & Egg, Rebecca
Partner: UNT Libraries Government Documents Department

Atmospheric Radiation Measurement Program facilities newsletter, July 2003.

Description: This Monthly newsletter discusses the following three topics: (1) Representative Lucas and Senator Myers Support SGP Site; (2) Broadband Outdoor Radiometer Calibration (BORCAL) Takes Place at SGP; and (3) ARM Program Research Featured in ''Science'' Magazine.
Date: August 7, 2003
Creator: Holdridge, D. J.
Partner: UNT Libraries Government Documents Department

THE ATOMIC WEIGHTS COMMISSION AND ISOTOPIC ABUNDANCE RATIO DETERMINATIONS.

Description: Following Thomson's discovery of stable isotopes in non-radioactive chemical elements, the derivation of atomic weight values from mass spectrometric measurements of isotopic abundance ratios moved very slowly. Forty years later, only 3 1/2 % of the recommended values were based on mass spectrometric measurements and only 38% in the first half century. It might be noted that two chemical elements (tellurium and mercury) are still based on chemical measurements, where the atomic weight value calculated from the relative isotopic abundance measurement either agrees with the value from the chemical measurement or the atomic weight value calculated from the relative isotopic abundance measurement falls within the uncertainty of the chemical measurement of the atomic weight. Of the 19 chemical elements, whose atomic weight is based on non-corrected relative isotopic abundance measurements, five of these are two isotope systems (indium, iridium, lanthanum, lutetium and tantalum) and one is a three-isotope system (oxygen).
Date: August 7, 2005
Creator: HOLDEN, N. E.
Partner: UNT Libraries Government Documents Department

ATPA Renewal: Background and Issues

Description: This report outlines the various aspects of the Andean Trade Preference Act (ATPA), including significant dates and modifications. The ATPA extends special duty treatment to certain U.S. imports from Bolivia, Colombia, Ecuador, and Peru that meet domestic content and other requirements. The purpose of ATPA is to promote economic growth in the Andean region and to encourage a shift away from dependence on illegal drugs by supporting legitimate economic activities.
Date: August 7, 2009
Creator: Villarreal, M. A.
Partner: UNT Libraries Government Documents Department

A,B,C`s of nuclear science

Description: This introductory level presentation contains information on nuclear structure, radioactivity, alpha decay, beta decay, gamma decay, half-life, nuclear reactions, fusion, fission, cosmic rays, and radiation protection. Nine experiments with procedures and test questions are included.
Date: August 7, 1995
Creator: Noto, V.A.; Norman, E.B.; Chan, Yuen-Dat; Dairiki, J.; Matis, H.S.; McMahan, M.A. et al.
Partner: UNT Libraries Government Documents Department

Bahrain: Reform, Security, and U.S. Policy

Description: This report discusses Bahrain's political structure and economy, the 2011 uprising and its aftereffects, human rights issues, security cooperation with the U.S., and foreign policy towards other countries in the region.
Date: August 7, 2017
Creator: Katzman, Kenneth
Partner: UNT Libraries Government Documents Department