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Actinide Biocolloid Formation in Brine by Halophilic Bacteria (open access)

Actinide Biocolloid Formation in Brine by Halophilic Bacteria

The authors examined the ability of a halophilic bacterium (WIPP 1A) isolated from the Waste Isolation Pilot Plant (WIPP) site to accumulate uranium in order to determine the potential for biocolloid facilitated actinide transport. The bacterial cell surface functional groups involved in the complexation of the actinide were determined by titration. Uranium, added as uranyl nitrate, was removed from solution at pH 5 by cells but at pH 7 and 9 very little uranium was removed due to its limited solubility. Although present as soluble species, uranyl citrate at pH 5, 7, and 9, and uranyl carbonate at pH 9 were not removed by the bacterium because they were not bioavailable due to their neutral or negative charge. Addition of uranyl EDTA to brine at pH 5, 7, and 9 resulted in the immediate precipitation of U. Transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS) analysis revealed that uranium was not only associated with the cell surface but also accumulated intracellularly as uranium-enriched granules. Extended X-ray absorption fine structure (EXAFS) analysis of the bacterial cells indicated the bulk sample contained more than one uranium phase. Nevertheless these results show the potential for the formation of actinide bearing bacterial …
Date: November 9, 1998
Creator: Gillow, J. B.; Francis, A. J.; Dodge, C. J.; Harris, R.; Beveridge, T. J.; Brady, P. B. et al.
Object Type: Article
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 99, No. 205, Ed. 1 Monday, November 9, 1998 (open access)

Altus Times (Altus, Okla.), Vol. 99, No. 205, Ed. 1 Monday, November 9, 1998

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: November 9, 1998
Creator: Cole, Carol
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Alvin Sun (Alvin, Tex.), Vol. 108, No. 28, Ed. 1 Monday, November 9, 1998 (open access)

The Alvin Sun (Alvin, Tex.), Vol. 108, No. 28, Ed. 1 Monday, November 9, 1998

Weekly newspaper from Alvin, Texas that includes local, state, and national news along with advertising.
Date: November 9, 1998
Creator: Schwind, Jim & Looby, Edward
Object Type: Newspaper
System: The Portal to Texas History
Appropriations for FY1999: VA, HUD, and Independent Agencies (open access)

Appropriations for FY1999: VA, HUD, and Independent Agencies

This report is a guide to one of the 13 regular appropriations bills that Congress considers each year. It is designed to supplement the information provided by the House and Senate Subcommittees on Veterans Affairs, Housing and Urban Development, and Independent Agencies Appropriations. It summarizes the current legislative status of the bill, its scope, major issues, funding levels, and related Congressional Research Service products.
Date: November 9, 1998
Creator: Snook, Dennis W.
Object Type: Report
System: The UNT Digital Library
Appropriations for FY1999: VA, HUD, and Independent Agencies (open access)

Appropriations for FY1999: VA, HUD, and Independent Agencies

Appropriations are one part of a complex federal budget process that includes budget resolutions, appropriations (regular, supplemental, and continuing) bills, rescissions, and budget reconciliation bills. This report is a guide to one of the 13 regular appropriations bills that Congress passes each year. It is designed to supplement the information provided by the House and Senate Subcommittees on VA, HUD and Independent Agencies Appropriations.
Date: November 9, 1998
Creator: Snook, Dennis W.
Object Type: Report
System: The UNT Digital Library
ATLAS: A Small, Light Weight, Time-Synchronized Wind-Turbine Data Acquistion System (open access)

ATLAS: A Small, Light Weight, Time-Synchronized Wind-Turbine Data Acquistion System

Wind energy researchers at Sandia National Laboratories have developed a small, lightweight, time- synchronized, robust data acquisition system to acquire long-term time-series data on a wind turbine rotor. A commercial data acquisition module is utilized to acquire data simultaneously from multip!e strain-gauge, analog, and digital channels. Acquisition of rotor data at precisely the same times as acquisition of ground data is ensured by slaving the acquisition clocks on the rotor- based data unit and ground-based units to the Global Positioning Satellite (GPS) system with commercial GPS receiver units and custom-built and programmed programmable logic devices. The acquisition clocks will remain synchronized within two microseconds indefinitely. Field tests have confirmed that synchronization can be maintained at rotation rates in excess of 350 rpm, Commercial spread-spectrum radio modems are used to transfer the rotor data to a ground- based computer concurrently with data acquisition, permitting continuous acquisition of data over a period of several hours, days or even weeks.
Date: November 9, 1998
Creator: Berg, D.E.; Robertson, P. & Zayas, J.
Object Type: Article
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 77, No. 8, Ed. 1 Monday, November 9, 1998 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 77, No. 8, Ed. 1 Monday, November 9, 1998

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: November 9, 1998
Creator: Dobbs, Gary
Object Type: Newspaper
System: The Portal to Texas History
Carbon Fluxes in a Managed Pine Forest Under Ambient and Elevated CO{sub 2} (open access)

Carbon Fluxes in a Managed Pine Forest Under Ambient and Elevated CO{sub 2}

The primary objective of this study is to estimate CO{sub 2} fluxes (F{sub CO{sub 2}}) under ambient and elevated atmospheric CO{sub 2}, and varying environmental conditions. Additional objectives are to: (2) quantify canopy conductance and evaluate the hypothesis that canopy conductance will not be altered by elevated atmospheric CO{sub 2} because reduction in leaf conductance is compensated by increased leaf area index, and (3) quantify the effect of elevated CO{sub 2} on aboveground production and apparent allocation of carbon below ground. In order to achieve the primary objective, the authors propose a modification to a methodology proposed earlier which emphasized leaf level measurements. These modifications stem from analysis of measurements performed in 1995--1996 that demonstrate (i) high variability in CO{sub 2} assimilation (A)--internal concentration (C{sub i} relations A-C{sub i} curves) in each level in the canopy for given photosynthetically active radiation (PAR) and soil moisture content ({theta}) conditions, (ii) the relative independence of the ratio of C{sub i} to atmospheric CO{sub 2} concentration (C{sub i}/C{sub a}) from C{sub a} (different levels within canopy for a wide range of moisture content conditions), (iii) similarity in CO{sub 2} and water vapor flux co-spectra which permits estimation of CO{sub 2} conductances from water …
Date: November 9, 1998
Creator: Oren, R.; Katul, G.; Schafer, K. & Hsieh, C. I.
Object Type: Report
System: The UNT Digital Library
Cone penetrometer demonstration standard startup review checklist (open access)

Cone penetrometer demonstration standard startup review checklist

Startup readiness for the Cone Penetrometer Demonstration in AX Tank Farm will be verified through the application of a Standard Startup Review Checklist. This is a listing of those items essential to demonstrating readiness to start the Cone Penetrometer Demonstration in AX Tank Farm.
Date: November 9, 1998
Creator: KRIEG, S.A.
Object Type: Report
System: The UNT Digital Library
Data Rich, Information Poor (open access)

Data Rich, Information Poor

Surviving in a data-rich environment means understanding the difference between data and information. This paper reviews an environmental case study that illustrates that understanding and shows its importance. In this study, a decision problem was stated in terms of au economic-objective fimction. The function contains a term that defines the stochastic relationship between the decision and the information obtained during field chamctetition for an environmental contaminant. Data is defied as samples drawn or experimental realizations of a mudom fimction. Information is defined as the quantitative change in the value of the objective fiction as a result of the sample.
Date: November 9, 1998
Creator: Kaplan, P. G. & Rautman, C. A.
Object Type: Article
System: The UNT Digital Library
Design package for fuel retrieval system fuel handling tool modification (open access)

Design package for fuel retrieval system fuel handling tool modification

This is a design package that contains the details for a modification to a tool used for moving fuel elements during loading of MCO Fuel Baskets for the Fuel Retrieval System. The tool is called the fuel handling tool (or stinger). This document contains requirements, development design information, tests, and test reports.
Date: November 9, 1998
Creator: TEDESCHI, D.J.
Object Type: Report
System: The UNT Digital Library
Design package Lazy Susan for the fuel retrieval system (open access)

Design package Lazy Susan for the fuel retrieval system

This is a design package that contains the details for a Lazy Susan style small tool for the Fuel Retrieval System. The Lazy Susan tool is used to help rotate an MCO Fuel Basket when loading it. This document contains requirements, development design information, tests and test reports that pertain to the production of Lazy Susan small tool.
Date: November 9, 1998
Creator: TEDESCHI, D.J.
Object Type: Report
System: The UNT Digital Library
A dynamic inert metal anode. (open access)

A dynamic inert metal anode.

A new concept for a stable anode for aluminum electrowinning is described. The anode consists of a cup-shaped metal alloy container filled with a molten salt that contains dissolved aluminum. The metal alloy can be any of a number of alloys, but it must contain aluminum as a secondary alloying metal. A possible alloy composition is copper with 5 to 15 weight percent aluminum. In the presence of oxygen, aluminum on the metal anode's exterior surface forms a continuous alumina film that is thick enough to protect the anode from chemical attack by cryolite during electrolysis and thin enough to maintain electrical conductivity. However, the alumina film is soluble in cryolite, so it must be regenerated in situ. Film regeneration is achieved by the transport of aluminum metal from the anode's molten salt interior through the metal wall to the anode's exterior surface, where the transported aluminum oxidizes to alumina in the presence of evolving oxygen to maintain the protective alumina film. Periodic addition of aluminum metal to the anode's interior keeps the aluminum activity in the molten salt at the desired level. This concept for an inert anode is viable as long as the amount of aluminum produced at …
Date: November 9, 1998
Creator: Hryn, J. N.
Object Type: Article
System: The UNT Digital Library
Elements of Doping Engineering in Semiconductors (open access)

Elements of Doping Engineering in Semiconductors

Using defect thermodynamics, we discuss physical factors that affect doping limits in semiconductors. The dependencies of the defect formation enthalpy on the atomic chemical potentials and on the electron Fermi energy are demonstrated. These dependencies, in particular on the Fermi energy, lead to spontaneous formation of charge-compensating defects that can limit doping. Experimental data compiled for III-V, II-VI, and I-III-VI2 compounds support this view and further provide insight into the connections among different host materials. We argue that what matters is not the magnitude of the band gap that determines the dopability of a material, but rather, the relative position of the conduction-band minimum (in the case of n-doping) and the valence-band maximum (in the case of p-doping) with respect to vacuum.
Date: November 9, 1998
Creator: Zhang, S. B.; Wei, S. & Zunger, A.
Object Type: Article
System: The UNT Digital Library
Environmental Protection Legislation in the 105th Congress (open access)

Environmental Protection Legislation in the 105th Congress

The 105th Congress enacted tax provisions relating to Superfund brownfields sites, transportation- and defense-related environmental provisions, a border smog bill, EPA funding as well as reinstating the tax that supports the Leaking Underground Storage Trust Fund. There were various actions on regulatory reform, the budget resolution, appropriations, highway- and defense-related environmental provisions, Superfund reform bills and underground storage tanks. It is too early to tell if these will be issues for the 106th Congress.
Date: November 9, 1998
Creator: Lee, Martin R.
Object Type: Report
System: The UNT Digital Library
Esperanzaite, NaCa(2)Al(2)(As(5+)O(4))[As(5+)O(3)(OH)](OH)(2)F(4)(H(2)O), A New Mineral From Mina La Esperanza, Mexico: Descriptive Mineralogy and Atomic Arrangement (open access)

Esperanzaite, NaCa(2)Al(2)(As(5+)O(4))[As(5+)O(3)(OH)](OH)(2)F(4)(H(2)O), A New Mineral From Mina La Esperanza, Mexico: Descriptive Mineralogy and Atomic Arrangement

Esperanzaite, ideally NaCazA12(As5+0.i)[As5+03 (OH)] (OH)2FJH20), Z =2, is a new mineral from the Mina h Esperarq Durango State, Mexico. The mineral occurs as blue-green botryoidal crystalline masses on rhyolite, with separate spheres up to 1.5 mm Y Deceased in diameter. Mobs hardness is 4.5, specific gravity 3.240h, and 3.36( 3)C.IC. Optical properties were measured in 589 nm light. Esperanzaite is biaxial (-), .Y= Y = Z= colorless, a 1.580(1), ~ 1.588( 1), and y 1.593(1 ); 2V0hs is 74(1 ~ and 2 }'CUIC is 76.3". Dispersion is medium, r < v, and optic axes are oriented as a A Z = +50.5o, b = Y, c P. X = +35". The five strongest X-ray diffraction maxima in the powder pattern are (~ /, hk~: 2.966,100, 13 i, 31 i, 031 ; 3.527,90, 220; 2.700,90,221,002, 040; 5.364>80, 001, 020; 4.796,80,011. Esperanzaite is monoclinic, u 9.687(5), b 10.7379(6), c 5.5523(7)& ~ 105.32( 1 )", space group P21/nz. The atomic arrangement of esperanzaite was solved by Direct Methods and Fourier analysis (R= 0.03 1). The Fundamental Building Block is formed of stacks of heteropolyhedral tetramers; the tetramers are formed of two arsenate tetrahedral and two Al octahedra, comer-linked in 4-member rings. The Fundamental …
Date: November 9, 1998
Creator: Cureton, F.; Falster, A. U.; Foord, E. E.; Hlava, P. F.; Hughes, J. M. & Maxwell, C. H.
Object Type: Article
System: The UNT Digital Library
Evaluation of 3 Commercially Available, On-Line TOC Analyzers for Monitoring Recycled Water in Semiconductor Processing (open access)

Evaluation of 3 Commercially Available, On-Line TOC Analyzers for Monitoring Recycled Water in Semiconductor Processing

Rapid detection of excursions in the concentration of organic contaminants in water that is being recycled is crucial to the more widespread acceptance of rinse water recycling as a method of reducing water usage in semiconductor manufacturing. In 1995 SEMATECH'SS116 PTAB (Project Technical Advisory Board) arbitrarily targeted a response time of 30s as the goal for the on-line detection of TOC (Total Oxidizable Carbon) in water - a goal thought to simpliilj the design of water recycling systems (less volume required for water storage in the recycle loop) and lead to more widespread adoption of recycling of spent rinse waters by the US semiconductor industry. A subsequent evaluation of the TOC analyzers commercially available in early 1996 demonstrated that the fastest response times were on the order of three minutes ljllef. 1]. This paper updates the 1996 evaluation of commercially available TOC analyzers by assessing modified versions of two of the previously evaluated analyzers and also anew analyzer that became commercially available in 1997.
Date: November 9, 1998
Creator: DeGenova, J.; Donovan, R.P. & Morrison, D.
Object Type: Article
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Monday, November 9, 1998 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Monday, November 9, 1998

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: November 9, 1998
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
GaN: Defect and Device Issues (open access)

GaN: Defect and Device Issues

The role of extended and point defects, and key impurities such as C, O and H, on the electrical and optical properties of GaN is reviewed. Recent progress in the development of high reliability contacts, thermal processing, dry and wet etching techniques, implantation doping and isolation and gate insulator technology is detailed. Finally, the performance of GaN-based electronic and photonic devices such as field effect transistors, UV detectors, laser diodes and light-emitting diodes is covered, along with the influence of process-induced or grown-in defects and impurities on the device physics.
Date: November 9, 1998
Creator: Pearton, S. J.; Ren, F.; Shul, R. J. & Zolper, J. C.
Object Type: Article
System: The UNT Digital Library
A Gas-Cooled Reactor Surface Power System (open access)

A Gas-Cooled Reactor Surface Power System

A human outpost on Mars requires plentiful power to assure survival of the astronauts. Anywhere from 50 to 500 kW of electric power (kWe) will be needed, depending on the number of astronauts, level of scientific activity, and life- cycle closure desired. This paper describes a 250-kWe power system based on a gas-cooled nuclear reactor with a recuperated closed Brayton cycle conversion system. The design draws upon the extensive data and engineering experience developed under the various high-temperature gas cooled reactor programs and under the SP-100 program. The reactor core is similar in power and size to the research reactors found on numerous university campuses. The fuel is uranium nitide clad in Nb 1 %Zr, which has been extensively tested under the SP-I 00 program The fiel rods are arranged in a hexagonal array within a BeO block. The BeO softens the spectrum, allowing better use of the fbel and stabilizing the geometty against deformation during impact or other loadings. The system has a negative temperature feedback coefficient so that the power level will automatically follow a variable load without the need for continuous adjustment of control elements. Waste heat is removed by an air-cooled heat exchanger using cold Martian …
Date: November 9, 1998
Creator: Harms, G.A.; Lenard, R.X.; Lipinski, R.J. & Wright, S.A.
Object Type: Article
System: The UNT Digital Library
Immigration: Visa Entry/Exit Control System (open access)

Immigration: Visa Entry/Exit Control System

This report provides background and analysis on Section 110 and issues related to increasing arrival/departure management at air, land border, and sea ports of entry.
Date: November 9, 1998
Creator: Krouse, William J. & Wasem, Ruth Ellen
Object Type: Report
System: The UNT Digital Library
Immigration: Visa Entry/Exit Control System (open access)

Immigration: Visa Entry/Exit Control System

Section 110 of the IllegalImmigrationReformand ImmigrantResponsibility Act of 1996 (IIRIRA; Division C of P.L. 104-208) mandates the development of an automated entry/exit control system to create a record for every alien departing from the United States and match it with the record for the alien arriving at the United States. Section 110 also requires that this system identify nonimmigrants who overstay the terms of their admission through online computer searching. The FY1999 Omnibus Consolidated and Emergency Supplemental Appropriations Act (P.L. 105-277) amends Section 110 to extend the original implementation deadline of September 30, 1998, to March 31, 2001, for land border and seaports of entry, but leaves the end of FY1998 deadline in place for airports of entry. Further, P.L. 105- 277 includes a clause directing that the entry/exit control system must “not significantly disrupt trade, tourism, or other legitimate cross-border traffic at land border ports of entry.”
Date: November 9, 1998
Creator: Krouse, William J. & Wasem, Ruth Ellen
Object Type: Report
System: The UNT Digital Library
Inelastic Neutron Scattering Study of Mn (open access)

Inelastic Neutron Scattering Study of Mn

The authors report zero-field inelastic neutron scattering experiments on a 14-gram deuterated sample of Mn{sub 12}-Acetate consisting of a large number of identical spin-10 magnetic clusters. Their resolution enables them to see a series of peaks corresponding to transitions between the anisotropy levels within the spin-10 manifold. A fit to the spin Hamiltonian H = {minus}DS{sub z}{sup 2} + {mu}{sub B}B{center_dot}g{center_dot}S-BS{sub z}{sup 4} + C(S{sub +}{sup 4} + S{sub {minus}}{sup 4}) yields an anisotropy constant D = (0.54 {+-} 0.02) K and a fourth-order diagonal anisotropy coefficient B = (1.2 {+-} 0.1) x 10{sup {minus}3}K. Unlike EPR measurements, their experiments do not require a magnetic field and yield parameters that do not require knowledge of the g-value.
Date: November 9, 1998
Creator: Zhong, Yicheng; Sarachik, M. P.; Friedman, Jonathan R.; Robinson, R. A.; Kelley, T. M.; Nakotte, H. et al.
Object Type: Article
System: The UNT Digital Library
Let's Not Panic Over the Year 2000 (open access)

Let's Not Panic Over the Year 2000

This report addresses various facts and myths concerning the Y2K (Year 2000) problem.
Date: November 9, 1998
Creator: Blackledge, M.A.
Object Type: Article
System: The UNT Digital Library