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Government Performance and Results Act and the Appropriations Process (open access)

Government Performance and Results Act and the Appropriations Process

congressional appropriations decisions for an agency or program are based generally on the following three factors: the amount of funding provided previously, the President's request, and the policy preferences of Congress. The Government Performance and Results Act of 1993 (GPRA, or the Results Act)
Date: August 27, 1998
Creator: Streeter, Sandy
Object Type: Report
System: The UNT Digital Library
The Yellow Jacket (Brownwood, Tex.), Vol. 89, No. 1, Ed. 1, Thursday, August 27, 1998 (open access)

The Yellow Jacket (Brownwood, Tex.), Vol. 89, No. 1, Ed. 1, Thursday, August 27, 1998

Weekly student newspaper from Howard Payne University in Brownwood, Texas that includes local, state and campus news along with advertising.
Date: August 27, 1998
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Cherokeean/Herald (Rusk, Tex.), Vol. 149, No. 27, Ed. 1 Thursday, August 27, 1998 (open access)

Cherokeean/Herald (Rusk, Tex.), Vol. 149, No. 27, Ed. 1 Thursday, August 27, 1998

Weekly newspaper from Rusk, Texas that includes local, state and national news along with extensive advertising.
Date: August 27, 1998
Creator: Whitehead, Marie
Object Type: Newspaper
System: The Portal to Texas History
Rio Grande Herald (Rio Grande City, Tex.), Vol. 85, No. 35, Ed. 1 Thursday, August 27, 1998 (open access)

Rio Grande Herald (Rio Grande City, Tex.), Vol. 85, No. 35, Ed. 1 Thursday, August 27, 1998

Weekly newspaper from Rio Grande City, Texas that includes local, state and national news along with extensive advertising.
Date: August 27, 1998
Creator: Roberts, Kenneth
Object Type: Newspaper
System: The Portal to Texas History
The Albany News (Albany, Tex.), Vol. 132, No. 13, Ed. 1 Thursday, August 27, 1998 (open access)

The Albany News (Albany, Tex.), Vol. 132, No. 13, Ed. 1 Thursday, August 27, 1998

Weekly newspaper from Albany, Texas that includes local, county, and state news along with extensive advertising.
Date: August 27, 1998
Creator: Lucas, Donnie A.
Object Type: Newspaper
System: The Portal to Texas History
The Canadian Record (Canadian, Tex.), Vol. 108, No. 35, Ed. 1 Thursday, August 27, 1998 (open access)

The Canadian Record (Canadian, Tex.), Vol. 108, No. 35, Ed. 1 Thursday, August 27, 1998

Weekly newspaper from Canadian, Texas that includes local, state and national news along with extensive advertising.
Date: August 27, 1998
Creator: Ezzell, Nancy & Brown, Laurie Ezzell
Object Type: Newspaper
System: The Portal to Texas History
First-principles calculation of atomic structure and electrochemical potential of Li{sub 1+x}V{sub 3}O{sub 8}. (open access)

First-principles calculation of atomic structure and electrochemical potential of Li{sub 1+x}V{sub 3}O{sub 8}.

Interest in the {gamma}-bronze, Li{sub 1+x}V{sub 3}O{sub g}, as a possible electrode material in rechargeable Li batteries has stimulated several experimental studies on this system. Detailed interpretation of the electrochemical and physical-property measurements is complicated by uncertainties regarding the structural arrangement of Li atoms as a function of x and by a phase transition between two monoclinic structures ({gamma}{sub a}, {gamma}{sub b}) during intercalation. To elucidate the atomic structures and the phase transition, first-principles calculations are performed with the local-density-functional-theory (LDFT) planewave pseudopotential method for both {gamma}{sub a} and {gamma}{sub b}, as a function of lithiation. Calculations for the compositions 1 + x = 1.5 and 1 + x = 4 confirm that the Li configuration determined in the existing x-ray diffraction structure refinements (at 1 + x = 1.2 and 1 + x = 4 respectively), coincide with the predicted low-energy configurations. Structure predictions were made at intermediate compositions, for which no experimental structure measurement is available. The order in which the tetrahedrally coordinated Li sites are filled at equilibrium as a function of x in {gamma}{sub a}, was predicted. Calculated electrochemical potentials as a function of composition agree well with experimental data.
Date: August 27, 1998
Creator: Benedek, R.
Object Type: Article
System: The UNT Digital Library
Mechanical and electrical properties of ZnO/Ag nanocomposites. (open access)

Mechanical and electrical properties of ZnO/Ag nanocomposites.

Effects of Ag particle dispersions on microstructural development and some properties were investigated for ZnO/Ag nanocomposites. They were fabricated by Pulse Electric Current Sintering (PECS) Process to achieve finer and densified microstructure. ZnO/Ag nanocomposites with novel microstructure which were prepared by a reduction process using Ag{sub 2}O fine powders were compared with microcomposites prepared by mixing of Ag and ZnO powders. SEM observation indicated that fine Ag particles were homogeneously dispersed within the ZnO matrix grains and at the grain boundaries for ZnO/Ag nanocomposites prepared by the reduction process using Ag{sub 2}O fine powder. Hardness and fracture toughness increased with increasing the Ag volume fraction. Linear resistivity was decreased with increasing Ag volume fraction. However, the mechanical and electrical properties appeared to the significantly different for composites prepared by two different powder processes.
Date: August 27, 1998
Creator: Hayashi, Y.
Object Type: Article
System: The UNT Digital Library
Removal of heavy metals from aqueous waste streams using surface-modified nanosized TiO{sub 2} photocatalysts. (open access)

Removal of heavy metals from aqueous waste streams using surface-modified nanosized TiO{sub 2} photocatalysts.

Titanium dioxide (TiO{sub 2}) colloidal particles ({approximately}45{angstrom}) whose surfaces were modified with chelating agents for photocatalytic removal of heavy-metal ions and their subsequent reduction to metallic form were investigated. Experiments were performed on nanoparticle TiO{sub 2} colloids derivatized with bidentate and tridentate ligands (thiolactic acid [TLA], cysteine, and alanine [ALA]) in batch mode in a photoreactor with 254nm light. We used catalysts designed and synthesized for selective and efficient removal of Pb and Cu with and without added hole scavenger (methanol). Parallel experiments also have been carried out in the dark to study metal ion adsorption properties. Solutions have been filtered to remove TiO{sub 2}, and metal particulates. Both the native solution and the metal deposited on the nanocrystalline TiO{sub 2} particles were analyzed. Results demonstrate that for the case of lead, the most effective TiO{sub 2} surface modifier was TLA (>99% Pb(II) removed from solution). Experiments performed to study Cn removal using TiO{sub 2} colloids modified with alanine showed that copper ions were effectively removed and reduced to metallic form in the presence of methanol.
Date: August 27, 1998
Creator: Meshkov, N. K.
Object Type: Article
System: The UNT Digital Library
Incident spectrum determination for time-of-flight neutron powder diffraction data analysis. (open access)

Incident spectrum determination for time-of-flight neutron powder diffraction data analysis.

Accurate characterization of the incident neutron spectrum is an important requirement for precise Rietveld analysis of time-of-flight powder neutron diffraction data. Without an accurate incident spectrum the calculated model for the measured relative intensities of individual Bragg reflections will possess systematic errors. We describe a method for obtaining an accurate numerical incident spectrum using data from a transmitted beam monitor.
Date: August 27, 1998
Creator: Hodges, J. P.
Object Type: Article
System: The UNT Digital Library
Longitudinal instability studies at the SURF II storage ring at NIST. (open access)

Longitudinal instability studies at the SURF II storage ring at NIST.

Measurements of the longitudinal instability observed in the storage ring at the Synchrotrons Ultraviolet Radiation Facility (SURF II) at the National Institute of Standards and Technology (NET) were performed to understand the mechanism driving the instability. The instability, studied in depth by Ralcowsky and others, manifests itself in broad resonance features in the horizontal and vertical motion spectrum of the synchrotrons light from DC to a few kHz. Also observed are multiple synchrotrons harmonics that modulate the revolution harmonics; these are characteristic of longitudinal phase oscillations. These spectral features of the motion are found to be correlated with the periodic lengthening and shortening of the bunch length on time scales from {approximately}0.1 ms to 20 ms, depending on machine and radio-frequency (rf) system parameters. In this report, the growth rate of the instability is determined from measurements using an rf pickup electrode. The measured growth rates are compared to computed growth rates from an analytical model. Recommendations are made regarding options to control or mitigate the instability. In light of upgrade plans for SURF III, a few comments are presented about the beam lifetime.
Date: August 27, 1998
Creator: Harkay, K.C. & Sereno, N.S.
Object Type: Report
System: The UNT Digital Library
Measurement of the critical current and transient characteristics of a high-temperature superconductor tube using a pulsed current supply. (open access)

Measurement of the critical current and transient characteristics of a high-temperature superconductor tube using a pulsed current supply.

The transient response of a melt-cast-processed BSCCO-2212 superconductor tube is investigated by using a pulsed current source. It was found that (1) the maximum induced current and the excitation current at field penetration increase with the maximum excitation current, and (2) there is a time delay between peak excitation current and peak magnetic field inside the superconductor. These observations can be explained by the concept of magnetic diffusion. The ac steady-state critical current of the superconductor was found to depend on the magnitude of the current increment. The critical current determined by using the pulsed current system agrees fairly well with the ac steady-state critical current determined by using relatively large current increment.
Date: August 27, 1998
Creator: Cha, Y. S.
Object Type: Article
System: The UNT Digital Library
Using synthetic model systems to understand charge separation and spin dynamics in photosynthetic reaction centers. (open access)

Using synthetic model systems to understand charge separation and spin dynamics in photosynthetic reaction centers.

Our current work in modeling reaction center dynamics has resulted in the observation of each major spin-dependent photochemical pathway that is observed in reaction centers. The development of new, simpler model systems has permitted us to probe deeply into the mechanistic issues that drive these dynamics. Based on these results we have returned to biomimetic chlorophyll-based electron donors to mimic these dynamics. Future studies will focus on the details of electronic structure and energetic of both the donor-acceptor molecules and their surrounding environment that dictate the mechanistic pathways and result in efficient photosynthetic charge separation.
Date: August 27, 1998
Creator: Wasielewski, M. R.
Object Type: Article
System: The UNT Digital Library
Graphical user interfaces for McCellan Nuclear Radiation Center (MNRC). (open access)

Graphical user interfaces for McCellan Nuclear Radiation Center (MNRC).

McClellan's Nuclear Radiation Center (MNRC) control console is in the process of being replaced due to spurious scrams, outdated software, and obsolete parts. The intent of the new control console is to eliminate the existing problems by installing a UNIX-based computer system with industry-standard interface software and incorporating human factors during all stages of the graphical user interface (GUI) development and control console design.
Date: August 27, 1998
Creator: Brown-VanHoozer, S. A.
Object Type: Article
System: The UNT Digital Library
Fall 1998 Visitors' Guide (Port Aransas, Tex.) (open access)

Fall 1998 Visitors' Guide (Port Aransas, Tex.)

Fall visitors' guide from Port Aransas, Texas that includes information of interest to visitors along with extensive advertising.
Date: August 27, 1998
Creator: Judson, Mary
Object Type: Newspaper
System: The Portal to Texas History
Hidden quasars in ultraluminous infared galaxies (open access)

Hidden quasars in ultraluminous infared galaxies

Abstract. Many ultraluminous infrared galaxies (ULIRGS) are pow- ered by quasars hidden in the center, but many are also powered by starbursts. A simply diagnostic diagram is proposed that can iden- tify obscured quasars in ULIRGs by their high-ionization emission lines ([0 III]X5007/HP ,? 5), and �warm� IR color (&/f6s 2 0.25).
Date: August 27, 1998
Creator: Brotherton, M. S.; Stanford, S. A.; Tran, H. & van Breugel, W.
Object Type: Article
System: The UNT Digital Library
Program desk manual for occupational safety and health -- U.S. Department of Energy Richland Operations, Office of Environment Safety and Health (open access)

Program desk manual for occupational safety and health -- U.S. Department of Energy Richland Operations, Office of Environment Safety and Health

The format of this manual is designed to make this valuable information easily accessible to the user as well as enjoyable to read. Each chapter contains common information such as Purpose, Scope, Policy and References, as well as information unique to the topic at hand. This manual can also be provided on a CD or Hanford Internet. Major topics include: Organization and program for operational safety; Occupational medicine; Construction and demolition; Material handling and storage; Hoisting and rigging; Explosives; Chemical hazards; Gas cylinders; Electrical; Boiler and pressure vessels; Industrial fire protection; Industrial hygiene; and Safety inspection checklist.
Date: August 27, 1998
Creator: Musen, L. G.
Object Type: Report
System: The UNT Digital Library
The Tulia Herald (Tulia, Tex.), Vol. 90, No. 35, Ed. 1 Thursday, August 27, 1998 (open access)

The Tulia Herald (Tulia, Tex.), Vol. 90, No. 35, Ed. 1 Thursday, August 27, 1998

Weekly newspaper from Tulia, Texas that includes local, state and national news along with extensive advertising.
Date: August 27, 1998
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Spatial frequency domain error budget (open access)

Spatial frequency domain error budget

The aim of this paper is to describe a methodology for designing and characterizing machines used to manufacture or inspect parts with spatial-frequency-based specifications. At Lawrence Livermore National Laboratory, one of our responsibilities is to design or select the appropriate machine tools to produce advanced optical and weapons systems. Recently, many of the component tolerances for these systems have been specified in terms of the spatial frequency content of residual errors on the surface. We typically use an error budget as a sensitivity analysis tool to ensure that the parts manufactured by a machine will meet the specified component tolerances. Error budgets provide the formalism whereby we account for all sources of uncertainty in a process, and sum them to arrive at a net prediction of how "precisely" a manufactured component can meet a target specification. Using the error budget, we are able to minimize risk during initial stages by ensuring that the machine will produce components that meet specifications before the machine is actually built or purchased. However, the current error budgeting procedure provides no formal mechanism for designing machines that can produce parts with spatial-frequency-based specifications. The output from the current error budgeting procedure is a single number …
Date: August 27, 1998
Creator: Hauschildt, H & Krulewich, D
Object Type: Article
System: The UNT Digital Library
Giving effective poster presentations (open access)

Giving effective poster presentations

Giving an effective poster presentation can be easy and rewarding with attention to a few proven concepts. Define your audience. Keep the words and graphics clear, concise, and eye-catching. Remember, you have three seconds to attract attention and 30 seconds to get your message across.
Date: August 27, 1998
Creator: Rice, J A
Object Type: Article
System: The UNT Digital Library
Development of a Radiative-Hydrodynamics Testbed Using the Petawatt Laser Facility (open access)

Development of a Radiative-Hydrodynamics Testbed Using the Petawatt Laser Facility

Many of the conditions believed to underlie astrophysical phenomena have been difficult to achieve in a laboratory setting. For example, models of supernova remnant evolution rely on a detailed understanding of the propagation of shock waves with gigabar pressures at temperatures of 1 keV or more where radiative effects can be important. Current models of gamma ray bursts posit a relativistically expanding plasma fireball with copious production of electron-positron pairs, a difficult scenario to experimentally verify. However, a new class of lasers, such as the Petawatt laser,Perry 1996 are capable of producing focused intensities greater than 10<sup>20</sup> W/cm&sup2; where such relativistic effects can be observed and even dominate the laser-target interaction. There is ample evidence in observational data from supernova remnants of the aftermath of the passage of radiative shock or blast waves. In the early phases of supernova remnant evolution, the radially-expanding shock wave expands nearly adiabatically since it is traveling at a very high velocity as it begins to sweep up the surrounding interstellar gas. A Sedov-Taylor blast wave solution can be applied to this phase,Taylor 1950, Sedov 1959 when the mass of interstellar gas swept up by the blast greatly exceeds the mass of the stellar ejecta, …
Date: August 27, 1998
Creator: Koch, J. A.; Bell, P. M.; Brown, C.; Budil, K. S.; Estabrook, K. G.; Gold, D. M. et al.
Object Type: Article
System: The UNT Digital Library
The dimensional stability of lightly-loaded epoxy joints (open access)

The dimensional stability of lightly-loaded epoxy joints

The use of adhesives to bond metal mounting structures to optical components can significantly simplify the design of an optical system. In precision applications, dimensional instability of the adhesive must be included as a component of the overall error budget. This paper describes the qualification testing of a balanced heterodyne interferometer system in a carefully controlled environment for the purpose of measuring joint stability. Results of this qualification test are reported.
Date: August 27, 1998
Creator: Badami, V G; Lawton, K M; Patterson, S R & Tajbakhsh, H
Object Type: Article
System: The UNT Digital Library
Three-degree-of-freedom optic mount for extreme ultraviolet lithography (open access)

Three-degree-of-freedom optic mount for extreme ultraviolet lithography

A mechanism to finely align optics for extreme ultraviolet lithography applications is presented. The mechanism is a small motion parallel link manipulator with flexure joints that exhibits nanometer level positioning capability. Performance results of a prototype system are given in this paper.
Date: August 27, 1998
Creator: Hale, L.; Jensen, S.; Malsbury, T.; Parker, J. & Tajbakhsh, H.
Object Type: Article
System: The UNT Digital Library
Port Aransas South Jetty (Port Aransas, Tex.), Vol. 28, No. 35, Ed. 1 Thursday, August 27, 1998 (open access)

Port Aransas South Jetty (Port Aransas, Tex.), Vol. 28, No. 35, Ed. 1 Thursday, August 27, 1998

Weekly newspaper from Port Aransas, Texas on Mustang Island that includes local, state and national news along with advertising.
Date: August 27, 1998
Creator: Judson, Mary
Object Type: Newspaper
System: The Portal to Texas History