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Analysis of volatile organic compounds in groundwater samples by gas chromatography-mass spectrometry

Description: The Savannah River Site contains approximately 1500 monitoring wells from which groundwater samples are collected. Many of these samples are sent off-site for various analyses, including the determination of trace volatile organic compounds (VOCs). This report describes accomplishments that have been made during the past year which will ultimately allow VOC analysis to be performed on-site using gas chromatography-mass spectrometry. Through the use of the on-site approach, it is expected that t… more
Date: August 23, 1995
Creator: Bernhardt, J.
Partner: UNT Libraries Government Documents Department
open access

Development of precipitated iron Fischer-Tropsch catalysts. Quarterly technical progress report, 1 January 1995--31 March 1995

Description: During the reporting period we completed synthesis of about 100 g of catalyst with nominal composition 100 Fe/3 Cu/4 K/16 SiO{sub 2} (S-3416-2), and of another batch (173 g) of the same catalyst (S-3416-3). Also, we synthesized two additional batches of catalyst with nominal composition 100 Fe/5 Cu/6 K/24 SiO{sub 2}, in the amounts of 240 g (S-5624-3) and 200 g (S-5624-4). These amounts are sufficient for all planned tests with these two catalysts for the entire duration of this contract. The s… more
Date: May 23, 1995
Creator: Bukur, D.B.; Lang, X. & Reddy, B.
Partner: UNT Libraries Government Documents Department
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Tributylphosphate in the In-Tank Precipitation Process Facilities

Description: A material balance investigation and evaluation of n- tributylphosphate (TBP) recycle throughout ITP and its carryover to Defense Waste Processing Facility (DWPF) was performed. Criticality and DWPF-related issues were determined to pose no adverse consequences due to TBP addition. Effects of decomposition products were also considered. Flammability of 1-butanol, a TBP decomposition product, in Tank 22 was investigated. Calculations show that Tank 22 would be ventilated with air at a rate suffi… more
Date: November 23, 1993
Creator: Barnes, M. J.; Hobbs, D. T. & Swingle, R. F.
Partner: UNT Libraries Government Documents Department
open access

Test plan for: TSAP bit qualification: Temperature criteria

Description: This is the Test Plan for acquiring TSAP bit temperature performance data. Hanford Site waste tanks are currently being sampled by several methods. One of these, Rotary Mode Core Sampling (RMCS), uses a cutting bit/sample tube arrangement to obtain core samples of tank contents. Recent efforts to improve sample recovery have resulted in a new bit/sample tube design. Prior to field use, bit performance in two key areas needs to be tested. These areas are: penetration into steel plate, and a temp… more
Date: October 23, 1995
Creator: Ralston, G.L.
Partner: UNT Libraries Government Documents Department
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New methods and materials for solid phase extraction and high performance liquid chromatography

Description: This paper describes methods for solid phase extraction and high performance liquid chromatography (HPLC). The following are described: Effects of Resin Sulfonation on the Retention of Polar Organic Compounds in Solid Phase Extraction; Ion-Chromatographic Separation of Alkali Metals In Non-Aqueous Solvents; Cation-Exchange Chromatography in Non-Aqueous Solvents; and Silicalite As a Stationary Phase For HPLC.
Date: April 23, 1996
Creator: Dumont, P.J.
Partner: UNT Libraries Government Documents Department
open access

Synthesis of Sol-Gel Matrices for Encapsulation of Enzymes Using an Aqueous Route

Description: Sol-gel matrices are promising host materials for potential chemical and biosensor applications. Previous studies have focused on modified sol-gel routes using alkoxides for encapsulation of enzymes. However the formation of alcohol as a byproduct during hydrolysis and condensation reactions poses limitations. We report the immobilization of glucose oxidase and peroxidase in silica prepared by an aqueous route which may provide a more favorable environment for the biomolecules. A two step aqueo… more
Date: November 23, 1998
Creator: Ashley, C. S.; Bhatia, R. B.; Brinker, C. J. & Harris, T. M.
Partner: UNT Libraries Government Documents Department
open access

Photodissociation dynamics of polyatomic molecules

Description: This report consists of five studies as follows: A laser photofragmentation time-of-flight mass spectrometric study of acetophenone at 193 and 248 nm; A 193 nm laser photofragmentation time-of-flight mass spectrometric study of dimethylsulfoxide; 193 nm laser photofragmentation time-of-flight mass spectrometric study of HSCH{sub 2}CH{sub 2}SH; Thiophene biradical decay of the primary laser photofragmentation product at 193 nm; and Scattering cross sections for O({sup 3}P)[SO(X,{sup 3}{Sigma}{su… more
Date: February 23, 1998
Creator: Zhao, H.
Partner: UNT Libraries Government Documents Department
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Interfacial characterization and analytical applications of chemically-modified surfaces

Description: The goal of this work is to explore several new strategies and approaches to the surface modification and the microscopic characterization of interfaces in the areas mainly targeting sensor technologies that are of interest to environmental control or monitoring, and scanning probe microscopies techniques that can monitor interfacial chemical reactions in real time. Centered on the main theme, four specific topics are presented as four chapters in this dissertation following the general introdu… more
Date: February 23, 1998
Creator: Wang, J.
Partner: UNT Libraries Government Documents Department
open access

FY97 report on moisture sensors for enhanced surveillance program project LL-ESP96-13

Description: Several compounds were evaluated in a number of optical configurations in order to test the optical response of these compounds to changes in humidity. Reichardt`s betaine (Reichardt`s dye, ET-30 dye, 2,6-diphenyl-4-(2,4,6-triphenyl-N-pyridinio)phenolate), a solvatochromic molecule, and several vapochromic compounds were tested, and each responded to a wide range of humidity by exhibiting shifts in visible absorption. All compounds in the study suffered from some degree of hysteresis upon humid… more
Date: September 23, 1997
Creator: Anderson, B. B.; Baylor, L. C. & Sanders, M. A.
Partner: UNT Libraries Government Documents Department
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Ion dip spectroscopy of cold molecules and ions. Progress report

Description: During the past year, the main emphasis in this research program has been on multiphoton ionization spectroscopy of aromatic clusters. This is being pursued in addition to continuing work in areas of ion dip spectroscopy and ion fragmentation spectroscopy. The program has the overall objective of developing improved ultrasensitive molecular detection methods based on multiphoton laser spectroscopy. Photoionization techniques are employed due to their extreme sensitivity combined with mass selec… more
Date: August 23, 1988
Creator: Wessel, J.E.
Partner: UNT Libraries Government Documents Department
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Direct Molecular Simulation of Gradient-Driven Diffusion of Large Molecules using Constant Pressure

Description: Dual control volume grand canonical molecular dynamics (DCV-GCMD) is a boundary-driven non-equilibrium molecular dynamics technique for simulating gradient driven diffusion in multi-component systems. Two control volumes are established at opposite ends of the simulation box. Constant temperature and chemical potential of diffusing species are imposed in the control volumes. This results in stable chemical potential gradients and steady-state diffusion fluxes in the region between the control v… more
Date: December 23, 1998
Creator: Heffelfinger, G. S. & Thompson, A. P.
Partner: UNT Libraries Government Documents Department
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Method of improving catalytic activity and catalytics produced thereby

Description: A process for dissociating H{sub 2}S in a gaseous feed using an improved catalytic material is disclosed in which the feed is contacted at a temperature of at least about 275C with a catalyst of rutile nanocrystalline titania having grain sizes in the range of from about 1 to about 100 manometers. Other transition metal catalysts are disclosed, each of nanocrystalline material with grain sizes in the 1--100 nm range. This invention may have application to vehicle emissions control (three-way ca… more
Date: September 23, 1993
Creator: Beck, D. D. & Siegel, R. W.
Partner: UNT Libraries Government Documents Department
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The crystal and molecular structure of azatranes: Azavanadatran (Z=t-Bu), monoazasilatrane (Z=H), azalithatrane (Z=Clo*4*), azaphosphatrane (Z=Me), azagermatrane (Z=t-Bu) and Azaalumatran (Z=nothing)

Description: The crystal and molecular structures of azatranes have been extensively studied for a variety of M atoms. The crystal and molecular structures of six similar cage compounds: (t-Bu)NV(MeNCH{sub 2}CH{sub 2}){sub 3}N, HSi(OCH{sub 2}CH{sub 2}){sub 2}(HNCH{sub 2}CH{sub 2})N, O{sub 4}ClLi(HNCH{sub 2}SH{sub 2}){sub 3}N, MeP(Me{sub 3}NCH{sub 2}CH{sub 2}){sub 3}N, t-BuGe(HNCH{sub 2}CH{sub 2}){sub 3}N, and Al(Me{sub 3}SiNCH{sub 2}CH{sub 2}){sub 3}N were determined by the use of three-dimensional, single … more
Date: April 23, 1996
Creator: Wang, T.
Partner: UNT Libraries Government Documents Department
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Examination of glass-silicon and glass-glass bonding techniques for microfluidic systems

Description: We report here on the results of experiments concerning particular bonding processes potentially useful for ultimate miniaturization of microfluidic systems. Direct anodic bonding of continuous thin pyrex glass of 250 {mu}m thickness to silicon substrates gives multiple, large voids in the glass. Etchback of thick glass of 1200 {mu}m thickness bonded to silicon substrates gives thin continuous glass layers of 189 {mu}m thickness without voids over areas of 5 cm {times} 12 cm. Glass was also suc… more
Date: October 23, 1995
Creator: Raley, N. F.; Davidson, J. C. & Balch, J. W.
Partner: UNT Libraries Government Documents Department
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Dynamical x-ray diffraction from an icosahedral Al-Pd-Mn quasicrystal

Description: Primary extinction effects in diffraction from single grains of Al-Pd- Mn, and presumably many other FCI alloys, may be significant and should be corrected for prior to use of diffraction data in structural determinations. Probes based on dynamical diffraction effects, such as x-ray standing wave fluorescence, multiple beam interference, and x-ray transmission topographs, may now be used to study the bulk and surface structure of some quasicrystals. The observation of dynamical diffraction from… more
Date: April 23, 1996
Creator: Kycia, S.
Partner: UNT Libraries Government Documents Department
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Direct catalytic conversion of methane and light hydrocarbon gases. Quarterly report No. 1, October 16, 1986--January 15, 1987

Description: The United States will need to be able to convert coal to liquid fuels should current supplies be interrupted. The indirect method for producing fuel liquids is the gasification of the coal to synthesis gas (syngas) followed by Fischer-Tropsch synthesis to convert syngas to hydrocarbons. However, both the gasifier and the FTS processes result in the production of methane and/or light hydrocarbon by-product that negatively affect the economics of the production of liquid fuel from coal. The goal… more
Date: February 23, 1987
Creator: Wilson, R. B., Jr. & Chan, Yee Wai
Partner: UNT Libraries Government Documents Department
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