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Financial Audit Manual: Volume Three, August 2007 (Supersedes GAO-07-313G) (open access)

Financial Audit Manual: Volume Three, August 2007 (Supersedes GAO-07-313G)

Guidance issued by the Government Accountability Office with an abstract that begins "This publication supersedes GAO-07-313G, Financial Audit Manual: Volume Three, Exposure Draft, June 2007. The U.S. Government Accountability Office (GAO) and the President's Council on Integrity and Efficiency (PCIE) maintain the GAO/PCIE Financial Audit Manual (FAM). The FAM provides guidance for performing financial statement audits of federal entities. The FAM is a key tool for enhancing accountability over taxpayer-provided resources."
Date: August 28, 2007
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Motor Carrier Safety: Federal Safety Agency Identifies Many High-Risk Carriers but Does Not Assess Maximum Fines as Often as Required by Law (open access)

Motor Carrier Safety: Federal Safety Agency Identifies Many High-Risk Carriers but Does Not Assess Maximum Fines as Often as Required by Law

A letter report issued by the Government Accountability Office with an abstract that begins "The Federal Motor Carrier Safety Administration (FMCSA) has the primary federal responsibility for reducing crashes involving large trucks and buses. FMCSA uses its "SafeStat" tool to target carriers for reviews of their compliance with the agency's safety regulations based on their crash rates and safety violations. As requested, this study reports on (1) the extent to which FMCSA's policy for prioritizing compliance reviews targets carriers with a high risk of crashes, (2) how FMCSA ensures compliance reviews are thorough and consistent, and (3) the extent to which FMCSA follows up with carriers with serious safety violations. To complete this work, GAO reviewed FMCSA's regulations, policies, and safety data and contacted FMCSA officials in headquarters and nine field offices."
Date: August 28, 2007
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Final Report - SRNL Agreement #AC51296V SEM, FIB, TEM Studies of CZT Samples (open access)

Final Report - SRNL Agreement #AC51296V SEM, FIB, TEM Studies of CZT Samples

The aims of this study are: (1) to characterize the surfaces of samples 3-7-8-3 and 4-1-3 using SEM, FIB and TEM techniques; (2) identify raised surface features; (3) prepare FIB-TEM lift-out sections from identified raised surfaces; and (4) perform detailed TEM characterization of FIB Sections. Focusing on the composition and crystallinity of the phases within the sections, including impurities.
Date: August 28, 2007
Creator: Bradley, J; Dai, Z R; Graham, G A & Teslich, N E
Object Type: Report
System: The UNT Digital Library
Effect of Organic Acid Additions on the General and Localized Corrosion Susceptibility of Alloy 22 in Chloride Solutions (open access)

Effect of Organic Acid Additions on the General and Localized Corrosion Susceptibility of Alloy 22 in Chloride Solutions

Electrochemical studies such as cyclic potentiodynamic polarization (CPP) and electrochemical impedance spectroscopy (EIS) were performed to determine the corrosion behavior of Alloy 22 (N06022) in 1M NaCl solutions at various pH values from acidic to neutral at 90 C. All the tested material was wrought Mill Annealed (MA). Tests were also performed in NaCl solutions containing weak organic acids such as oxalic, acetic, citric and picric. Results show that the corrosion rate of Alloy 22 was significantly higher in solutions containing oxalic acid than in solutions of pure NaCl at the same pH. Citric and picric acids showed a slightly higher corrosion rate, and acetic acid maintained the corrosion rate of pure chloride solutions at the same pH. Organic acids revealed to be weak inhibitors for crevice corrosion. Higher concentration ratios, compared to nitrate ions, were needed to completely inhibit crevice corrosion in chloride solutions. Results are discussed considering acid dissociation constants, buffer capacity and complex formation constants of the different weak acids.
Date: August 28, 2007
Creator: Carranza, R M; Giordano, C M; Rodr?guez, M A; Ilevbare, G O & Rebak, R B
Object Type: Article
System: The UNT Digital Library
Development of Wind-and-React Bi-2212 Accelerator MagnetTechnology (open access)

Development of Wind-and-React Bi-2212 Accelerator MagnetTechnology

We report on the progress in our R&D program, targetedto develop the technology for the application of Bi2Sr2CaCu2Ox (Bi-2212)in accelerator magnets. The program uses subscale coils, wound frominsulated cables, to study suitable materials, heat treatmenthomogeneity, stability, and effects ofmagnetic field and thermal andelectro-magnetic loads. We have addressed material and reaction relatedissues and report onthe fabrication, heat treatment, and analysis ofsubscale Bi-2212 coils. Such coils can carry a current on the order of5000 A and generate, in various support structures, magnetic fields from2.6 to 9.9 T. Successful coils are therefore targeted towards a hybridNb3Sn-HTS magnet which will demonstrate the feasibility of Bi-2212 foraccelerator magnets, and open a new magnetic field realm, beyond what isachievable with Nb3Sn.
Date: August 28, 2007
Creator: Godeke, A.; Cheng, D.; Dietderich, D. R.; English, C. D.; Felice, H.; Hannaford, C. R. et al.
Object Type: Article
System: The UNT Digital Library
Accounting for false negatives in hotspot detection (open access)

Accounting for false negatives in hotspot detection

Hotspot sampling designs are used in environmental sampling to identify the location of one (or more) contiguous regions of elevated contamination. These regions are known as hotspots. The problem of how to calculate the probability of detecting an elliptical hotspot using a rectangular or triangular grid of sampling points was addressed by Singer and Wickman in 1969. This approach presumed that any sample which coincided with a hotspot would detect the hotspot without error. However, for many sampling methodologies, there is a chance that the hotspot will not be detected even though it has been sampled directly--a false negative. We present a mathematical solution and a numerical algorithm which account for false negatives when calculating the probability of detecting hotspots that are circular in shape.
Date: August 28, 2007
Creator: Sego, Landon H. & Wilson, John E.
Object Type: Report
System: The UNT Digital Library
Osmose Program : Statistical Review of Oscillation Measurements in the Minerve Reactor r1-uo2 Configuration. (open access)

Osmose Program : Statistical Review of Oscillation Measurements in the Minerve Reactor r1-uo2 Configuration.

The OSMOSE program is a collaboration on reactor physics experiments between the United States Department of Energy and the France Commissariat Energie Atomique. At the working level, it is a collaborative effort between the Argonne National Laboratory and the CEA Cadarache Research Center. The objective of this program is to measure very accurate integral reaction rates in representative spectra for the actinides important to future nuclear system designs, and to provide the experimental data for improving the basic nuclear data files. The main outcome of the OSMOSE measurement program will be an experimental database of reactivity-worth measurements in different neutron spectra for the heavy nuclides. This database can then be used as a benchmark to verify and validate reactor analysis codes. The OSMOSE program (Oscillation in Minerve of isotopes in Eupraxic Spectra) aims at improving neutronic predictions of advanced nuclear fuels through oscillation measurements in the MINERVE facility on samples containing the following separated actinides: {sup 232}Th, {sup 233}U, {sup 234}U, {sup 235}U, {sup 236}U, {sup 238}U, {sup 237}Np, {sup 238}Pu, {sup 239}Pu, {sup 240}Pu, {sup 241}Pu, {sup 242}Pu, {sup 241}Am, {sup 243}Am, {sup 244}Cm, and {sup 245}Cm. The first part of this report provides an overview of the experimental …
Date: August 28, 2007
Creator: Stoven, G.; Klann, R. & Zhong, Z.
Object Type: Report
System: The UNT Digital Library
Modeling cation diffusion in compacted water-saturatedNa-bentonite at low ionic strength (open access)

Modeling cation diffusion in compacted water-saturatedNa-bentonite at low ionic strength

Sodium bentonites are used as barrier materials for the isolation of landfills and are under consideration for a similar use in the subsurface storage of high-level radioactive waste. The performance of these barriers is determined in large part by molecular diffusion in the bentonite pore space. We tested two current models of cation diffusion in bentonite against experimental data on the relative apparent diffusion coefficients of two representative cations, sodium and strontium. On the 'macropore/nanopore' model, solute molecules are divided into two categories, with unequal pore-scale diffusion coefficients, based on location: in macropores or in interlayer nanopores. On the 'surface diffusion' model, solute molecules are divided into categories based on chemical speciation: dissolved or adsorbed. The macropore/nanopore model agrees with all experimental data at partial montmorillonite dry densities ranging from 0.2 (a dilute bentonite gel) to 1.7 kg dm{sup -3} (a highly compacted bentonite with most of its pore space located in interlayer nanopores), whereas the surface diffusion model fails at partial montmorillonite dry densities greater than about 1.2 kg dm{sup -3}.
Date: August 28, 2007
Creator: Bourg, Ian C.; Sposito, Garrison & Bourg, Alain C.M.
Object Type: Article
System: The UNT Digital Library
The Resolution of Chiral, Tetrahedral M4L6 Metal-LigandHosts (open access)

The Resolution of Chiral, Tetrahedral M4L6 Metal-LigandHosts

The supramolecular metal-ligand assemblies of M{sub 4}1{sub 6} stoichiometry are chiral (M = Ga{sup III}, Al{sup III}, In{sup III}, Fe{sup III}, Ti{sup IV}, or Ge{sup IV}, H{sub 4}1 = N,N'-bis(2,3-dihydroxybenzoyl)-1,5-diaminonaphthalene). The resolution process of {Delta}{Delta}{Delta}{Delta}- and {Lambda}{Lambda}{Lambda}{Lambda}-[M{sub 4}1{sub 6}]{sup 12-} by the chiral cation s-nicotinium (S-nic{sup +}) is described for the Ga{sup III}, Al{sup III}, and Fe{sup III} assemblies, and the resolution is shown to be proton dependent. From a methanol solution of M(acac){sub 3}, H{sub 4}1, S-nicI, and KOH, the {Delta}{Delta}{Delta}{Delta}-KH{sub 3}(S-nic){sub 7}[(S-nic) {contained_in}M{sub 4}1{sub 6}] complexes precipitate, and the {Lambda}{Lambda}{Lambda}{Lambda}-K{sub 6}(S-nic){sub 5}[(S-nic) {contained_in} M{sub 4}1{sub 6}] complexes subsequently can be isolated from the supernatant. Ion exchange enables the isolation of the (NEt{sub 4}{sup +}){sub 12}, (NMe{sub 4}{sup +}){sub 12} and K{sub 12}{sup +} salts of the resolved structures, which have been characterized by CD and NMR spectroscopies. Resolution can also be accomplished with one equivalent of NEt{sub 4}{sup +} blocking the cavity interior, demonstrating that external binding sites are responsible for the difference in S-nic{sup +} enantiomer interactions. Circular dichroism data demonstrate that the (NMe{sub 4}{sup +}){sub 12} and (NEt{sub 4}{sup +}){sub 12} salts of the resolved [Ga{sub 4}1{sub 6}]{sup 12-} and [Al{sub 4}1{sub 6}]{sup 12-} structures retain …
Date: August 28, 2007
Creator: Davis, Anna V.; Fiedler, Dorothea; Ziegler, Marco; Terpin,Andreas & Raymond, Kenneth N.
Object Type: Article
System: The UNT Digital Library
Preparing for Ignition Experiments on the National Ignition Facility (open access)

Preparing for Ignition Experiments on the National Ignition Facility

The National Ignition Facility (NIF) is a 192-beam Nd-glass laser facility presently under construction at Lawrence Livermore National Laboratory (LLNL) for performing ignition experiments for inertial confinement fusion (ICF) and experiments studying high energy density (HED) science. NIF will produce 1.8 MJ, 500 TW of ultraviolet light ({lambda} = 351 nm) making it the world's largest and most powerful laser system. NIF will be the world's preeminent facility for the study of matter at extreme temperatures and densities for producing and developing ICF. The ignition studies will be an essential step in developing inertial fusion energy (IFE). the NIF Project is over 93% complete and scheduled for completion in 2009. Experiments using one beam have demonstrated that NIF can meet all of its performance goals. A detailed plan called the National Ignition Campaign (NIC) has been developed to begin ignition experiments in 2010. The plan includes the target physics and the equipment such as diagnostics, cryogenic target manipulator and user optics required for the ignition experiment. Target designs have been developed that calculate to ignite at energy as low as 1 MJ. Plans are under way to make NIF a national user facility for experiments on HED physics and nuclear …
Date: August 28, 2007
Creator: Moses, E & Meier, W
Object Type: Article
System: The UNT Digital Library
Physics of Plasma-Based Ion Implantation&Deposition (PBIID)and High Power Impulse Magnetron Sputtering (HIPIMS): A Comparison (open access)

Physics of Plasma-Based Ion Implantation&Deposition (PBIID)and High Power Impulse Magnetron Sputtering (HIPIMS): A Comparison

The emerging technology of High Power Impulse MagnetronSputtering (HIPIMS) has much in common with the more establishedtechnology of Plasma Based Ion Implantation&Deposition (PBIID):both use pulsed plasmas, the pulsed sheath periodically evolves andcollapses, the plasma-sheath system interacts with the pulse-drivingpower supply, the plasma parameters are affected by the power dissipated,surface atoms are sputtered and secondary electrons are emitted, etc.Therefore, both fields of science and technology could learn from eachother, which has not been fully explored. On the other hand, there aresignificant differences, too. Most importantly, the operation of HIPIMSheavilyrelies on the presence of a strong magnetic field, confiningelectrons and causing their ExB drift, which is closed for typicalmagnetron configurations. Second, at the high peak power levels used forHIPIMS, 1 kW/cm2 or greater averaged over the target area, the sputteredmaterial greatly affects plasma generation. For PBIID, in contrast,plasma generation and ion processing of the surface (ion implantation,etching, and deposition) are considered rela-tively independentprocesses. Third, secondary electron emission is generally considered anuisance for PBIID, especially at high voltages, whereas it is a criticalingredient to the operation of HIPIMS. Fourth, the voltages in PBIID areoften higher than in HIPIMS. For the first three reasons listed above,modelling of PBIID seems to be easier and could …
Date: August 28, 2007
Creator: Anders, Andre
Object Type: Article
System: The UNT Digital Library
Analysis of stress sensitivity and its influence on oil productionfrom tight reservoirs (open access)

Analysis of stress sensitivity and its influence on oil productionfrom tight reservoirs

This paper presents a study of the relationship betweenpermeability and effective stress in tight petroleum reservoirformations. Specifically, a quantitative method is developed to describethe correlation between permeability and effective stress, a method basedon the original in situ reservoir effective stress rather than ondecreased effective stress during development. The experimental resultsshow that the relationship between intrinsic permeability and effectivestress in reservoirs in general follows a quadratic polynomial functionalform, found to best capture how effective stress influences formationpermeability. In addition, this experimental study reveals that changesin formation permeability, caused by both elastic and plasticdeformation, are permanent and irreversible. Related pore-deformationtests using electronic microscope scanning and constant-rate mercuryinjection techniques show that while stress variation generally has smallimpact onrock porosity, the size and shape of pore throats have asignificant impact on permeability-stress sensitivity. Based on the testresults and theoretical analyses, we believe that there exists a cone ofpressure depression in the area near production within suchstress-sensitive tight reservoirs, leading to a low-permeability zone,and that well production will decrease under the influence of stresssensitivity.
Date: August 28, 2007
Creator: Lei, Qun; Xiong, Wei; Yuan, Cui & Wu, Yu-Shu
Object Type: Article
System: The UNT Digital Library
Extension of the operating parameters of the two stage light gas gun to velocities below 2 km/sec. (open access)

Extension of the operating parameters of the two stage light gas gun to velocities below 2 km/sec.

The Joint Actinide Shock Physics Experimental Facility (JASPER) located in area 27 at the Nevada Test Site Has been tasked with providing high accuracy information on the Equation Of State (EOS) and other dynamic properties of weapons grade plutonium and other actinides important to the stockpile stewardship program. In the past 5 years this facility has provided dozens of experimental data points for the accurate determination of pressure density relationship for these materials over a broad pressure range. In order to complete this survey it is necessary to extend the low pressure region to include projectile velocities below 2 km/s. For most gas gun facilities this would present not too great a difficulty, one could simply decrease the amount of propellant along with a decrease in the strength of the petal valve, However JASPER requires that the piston be securely embedded in the Acceleration Reservoir (AR) as part of the containment system. The projectile must remain flat and undistorted. This requirement makes the attainment of slow velocities problematic. This talk will discuss the JASPER Facility, A finite difference code developed to give predictive capability for two stage gas guns, and a set of experiments performed to demonstrate this capability.
Date: August 28, 2007
Creator: Thoe, R S
Object Type: Article
System: The UNT Digital Library
Final work plan for targeted investigation at Hilton, Kansas. (open access)

Final work plan for targeted investigation at Hilton, Kansas.

This Work Plan outlines the scope of a targeted investigation to update the status of carbon tetrachloride contamination in groundwater associated with grain storage operations at Hilton, Kansas. The Commodity Credit Corporation (CCC), an agency of the U.S. Department of Agriculture (USDA), operated a grain storage facility in Hilton during the 1950s and 1960s. At the time of the CCC/USDA operation in Hilton, grain storage facilities (CCC/USDA and private) were located along the both sides of the former Union Pacific railroad tracks (Figure 1.1). The main grain storage structures were on or near the railroad right-of-way. The proposed targeted investigation, to be conducted by Argonne National Laboratory on the behalf of CCC/USDA, will supplement Argonne's Phase I and Phase II investigations in 1996-1997. The earlier investigations erroneously focused on an area east of the railroad property where the CCC/USDA did not operate, specifically on a private grain storage facility. In addition, the investigation was limited in scope, because access to railroad property was denied (Argonne 1997a,b). The hydrogeologic system at Hilton is potentially complex.
Date: August 28, 2007
Creator: LaFreniere, L. M.
Object Type: Report
System: The UNT Digital Library
Greensheet (Houston, Tex.), Vol. 38, No. 350, Ed. 1 Tuesday, August 28, 2007 (open access)

Greensheet (Houston, Tex.), Vol. 38, No. 350, Ed. 1 Tuesday, August 28, 2007

Free weekly newspaper that includes business and classified advertising.
Date: August 28, 2007
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Greensheet (Houston, Tex.), Vol. 38, No. 349, Ed. 1 Tuesday, August 28, 2007 (open access)

Greensheet (Houston, Tex.), Vol. 38, No. 349, Ed. 1 Tuesday, August 28, 2007

Free weekly newspaper that includes business and classified advertising.
Date: August 28, 2007
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
North Texas Daily (Denton, Tex.), Vol. 91, No. 116, Ed. 1 Tuesday, August 28, 2007 (open access)

North Texas Daily (Denton, Tex.), Vol. 91, No. 116, Ed. 1 Tuesday, August 28, 2007

Daily student newspaper from the University of North Texas in Denton, Texas that includes local, state and campus news along with advertising.
Date: August 28, 2007
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
What Happens if SCHIP Is Not “Reauthorized”? (open access)

What Happens if SCHIP Is Not “Reauthorized”?

None
Date: August 28, 2007
Creator: Peterson, Chris L.
Object Type: Report
System: The UNT Digital Library
Former Speakers of the House: Office Allowances, Franking Privileges, and Staff Assistance (open access)

Former Speakers of the House: Office Allowances, Franking Privileges, and Staff Assistance

This report is categorized into six categories: (I) Allowances Made Available in 1959, (II) Allowances Made Available in 1970, (III) Allowances Made Available in 1974, (IV) Changes in Allowances, 1974-Present ,(V) Allowances Currently Available to Former Speakers, (VI) Restrictions on Use of Allowances by Former Speakers.
Date: August 28, 2007
Creator: Glassman, Matthew Eric
Object Type: Report
System: The UNT Digital Library
[Conference call invitation] (open access)

[Conference call invitation]

Email correspondence between board members on August 28, 2007, addressing conference call invitation for September 2, 2007.
Date: August 28, 2007
Creator: unknown
Object Type: Text
System: The UNT Digital Library
Pipeline Removal vs. Characterization Study (open access)

Pipeline Removal vs. Characterization Study

None
Date: August 28, 2007
Creator: Jasen, W. G.; Gaul, W.; Hickey, M. J. & Urland, C.
Object Type: Report
System: The UNT Digital Library
A triple-continuum pressure-transient model for a naturallyfractured vuggy reservoir (open access)

A triple-continuum pressure-transient model for a naturallyfractured vuggy reservoir

We present an analytical approach for pressure transienttest analysis in naturally fractured vuggy reservoirs. This analysisapproach relies on a triple-continuum concept, using observed geologicaldata from carbonate oil formations in western China, to describetransient flow behavior in fracture-vug-matrix reservoirs. In theconceptual mathematical model, fractured vuggy rock is considered as atriple-continuum medium, consisting of fractures, rock matrix, and vugs(or cavities). Similar to the classical double-porosity model, thefracture continuum is assumed to be responsible for the occurrence ofglobal flow, while vuggy and matrix continua (providing primary storagespace) interact locally with each other as well as with globallyconnected fractures. Furthermore, the triple continua of fractures,matrix, and vugs are assumed to have uniform and homogeneous propertiesthroughout, and intercontinuum flows between them are at pseudosteadystate. With these assumptions, we derive analytical solutions in Laplacespace for transient flow toward a well in an infinite and finitereservoir with wellbore storage and skin effects. The analyticalsolutions reveal typical pressure responses in a fracture-vug-matrixreservoir and can be used for estimating vug properties, in addition tofracture and matrix parameters, through properly designed and conductedwell tests. As application examples, actual well test data from afractured-vuggy reservoir in Western China are analyzed using the triplecontinuum model.
Date: August 28, 2007
Creator: Wu, Y-S.; Ehlig-Economides, C.; Qin, Guan; Kang, Zhijang; Zhang,Wangming; Ajayi, Babatunde et al.
Object Type: Article
System: The UNT Digital Library
NEW COLUMN SEPARATION METHOD FOR EMERGENCY URINE SAMPLES (open access)

NEW COLUMN SEPARATION METHOD FOR EMERGENCY URINE SAMPLES

The Savannah River Site Environmental Bioassay Lab participated in the 2007 NRIP Emergency Response program administered by the National Institute for Standards and Technology (NIST) in May, 2007. A new rapid column separation method was applied directly to the NRIP 2007 emergency urine samples, with only minimal sample preparation to reduce preparation time. Calcium phosphate precipitation, previously used to pre-concentrate actinides and Sr-90 in NRIP 2006 urine and water samples, was not used for the NRIP 2007 urine samples. Instead, the raw urine was acidified and passed directly through the stacked resin columns (TEVA+TRU+SR Resins) to separate the actinides and strontium from the NRIP urine samples more quickly. This improvement reduced sample preparation time for the NRIP 2007 emergency urine analyses significantly. This approach works well for small volume urine samples expected during an emergency response event. Based on initial feedback from NIST, the SRS Environmental Bioassay Lab had the most rapid analysis times for actinides and strontium-90 analyses for NRIP 2007 urine samples.
Date: August 28, 2007
Creator: Maxwell, S & Brian Culligan, B
Object Type: Article
System: The UNT Digital Library
Hierarchical Material Models for Fragmentation Modeling in NIF-ALE-AMR (open access)

Hierarchical Material Models for Fragmentation Modeling in NIF-ALE-AMR

Fragmentation is a fundamental process that naturally spans micro to macroscopic scales. Recent advances in algorithms, computer simulations, and hardware enable us to connect the continuum to microstructural regimes in a real simulation through a heterogeneous multiscale mathematical model. We apply this model to the problem of predicting how targets in the NIF chamber dismantle, so that optics and diagnostics can be protected from damage. The mechanics of the initial material fracture depend on the microscopic grain structure. In order to effectively simulate the fragmentation, this process must be modeled at the subgrain level with computationally expensive crystal plasticity models. However, there are not enough computational resources to model the entire NIF target at this microscopic scale. In order to accomplish these calculations, a hierarchical material model (HMM) is being developed. The HMM will allow fine-scale modeling of the initial fragmentation using computationally expensive crystal plasticity, while the elements at the mesoscale can use polycrystal models, and the macroscopic elements use analytical flow stress models. The HMM framework is built upon an adaptive mesh refinement (AMR) capability. We present progress in implementing the HMM in the NIF-ALE-AMR code. Additionally, we present test simulations relevant to NIF targets.
Date: August 28, 2007
Creator: Fisher, A.; Masters, N.; Koniges, A.; Anderson, R.; Gunney, B.; Wang, P. et al.
Object Type: Article
System: The UNT Digital Library