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Vicarious amination of nitroarenes with trimethylhydrazinium iodine

Description: This paper investigated the use of 1,1,1-trimethylhydrazinium iodide as a vicarious nucleophilic substitution reagent for introducing amino groups into nitroaromatic substrates. The substrates included nitroarenes, polynitrobenzenes, picramide, TNB,TNT, and dinitropyrazole; other nitroazoles are being studied.
Date: November 10, 1995
Creator: Pagoria, P.F.; Schmidt, R.D. & Mitchell, A.R.
Partner: UNT Libraries Government Documents Department

Conversion of the rocket propellant UDMH to a reagent useful in vicarious nucleophilic substitution reactions

Description: The objective of our program is to develop novel, innovative solutions for the disposal of surplus energetic materials resulting from the demilitarization of conventional and nuclear munitions. In this report we describe the use of surplus propellant (UDMH) and explosives (TNT, Explosive D) as chemical precursors for higher value products. The conversion of UDMH to 1,1,1-trimethylhydrazinium iodide (TMHI) provides a new aminating reagent for use in Vicarious Nucleophilic Substitution (VNS) reactions. When TMHI is reacted with various nitroarenes the amino functionality is introduced in good to excellent yields. Thus, 2,4,6-trinitroaniline (picramide) reacts with TMHI to give 1,3,5-triamino-2,4,6-trinitroaniline (TATB) while 2,4,6-trinitrotoluene (TNT) reacts with TMHI to give 3,5-diamino-2,4,6-trinitrotoluene (DATNT). The advantages, scope and limitations of the VNS approach and the use of TMHI are discussed.
Date: November 10, 1995
Creator: Mitchell, A.R.; Pagoria, P.F. & Schmidt, R.D.
Partner: UNT Libraries Government Documents Department

Scanning probe microscopies for the creation and characterization of interfacial architectures: Studies of alkyl thiolate monolayers at gold

Description: Scanning probe microscopy (SPM) offers access to the structural and material properties of interfaces, and when combined with macroscopic characterization techniques results in a powerful interfacial development tool. However, the relative infancy of SPM techniques has dictated that initial investigations concentrate on model interfacial systems as benchmarks for testing the control and characterization capabilities of SPM. One such family of model interfacial systems results from the spontaneous adsorption of alkyl thiols to gold. This dissertation examines the application of SPM to the investigation of the interfacial properties of these alkyl thiolate monolayers. Structural investigations result in a proposed explanation for counterintuitive correlations between substrate roughness and heterogeneous electron transfer barrier properties. Frictional measurements are used for characterization of the surface free energy of a series of end-group functionalized monolayers, as well as for the material properties of monolayers composed of varying chain length alkyl thiols. Additional investigations used these characterization techniques to monitor the real-time evolution of chemical and electrochemical surface reactions. The results of these investigations demonstrates the value of SPM technology to the compositional mapping of surfaces, elucidation of interfacial defects, creation of molecularly sized chemically heterogeneous architectures, as well as to the monitoring of surface reactions. However, it is the future which will demonstrate the usefulness of SPM technology to the advancement of science and technology.
Date: January 10, 1997
Creator: Green, J.
Partner: UNT Libraries Government Documents Department

Extension of Studies with 3M Empore TM and Selentec MAG *SEP SM Technologies for Improved Radionuclide Field Sampling

Description: The Savannah River Technology Center is evaluating new field sampling methodologies to more easily determine concentrations of radionuclides in aqueous systems. One methodology studied makes use of 3M EmporeTM disks. The disks are composed of selective resins embedded in a Teflon support. The disks remove the ion of interest from aqueous solutions when the solution is passed through the disk. The disk can then be counted directly to quantify the isotope of interest. Four types of disks were studied during this work: for the extraction of technetium (two types), cesium, plutonium, and strontium. A sampler has been developed for automated, unattended, in situ use of the EmporeTM disks.
Date: July 10, 1996
Creator: Beals, D.M.; Bibler, J.P. & Brooks, D.A.
Partner: UNT Libraries Government Documents Department

Steam pretreatment for coal liquefaction. [Monthly report], November 1, 1993--November 30, 1993

Description: Two slow heating liquefaction runs of steam pretreated coal were carried out using the new sample (No.31) of Illinois No.6 coal to check consistency with previous samples. Good agreement was obtained between the runs made with new sample. There were, however, significant differences from yields obtained with the previously used sample. Consequently, averaging yields from the two samples is not appropriate. Further work on this new Illinois No.6 coal sample will be continued next month. Purification of {alpha}-naphthylmethyl phenyl ether, and {alpha}-benzylnaphthyl ether was continued.
Date: December 10, 1993
Partner: UNT Libraries Government Documents Department

Steam pretreatment for coal liquefaction. [Monthly report], September 1, 1993--September 30, 1993

Description: Rapid heating liquefaction of steam pretreated Illinois No.6 coal mixed with 4A zeolite was carried out this month. Liquefaction yields are close to those obtained with 5A zeolite at the same coal/zeolite ration. Aquathermolysis of model compound 9-phenoxyphenanthrene was carried out this month under conditions similar to employed by Katritzky but for shorter time. Analysis of recovered products showed incomplete cleavage of the ether. This demonstrates the importance of longer reaction time even at high pressure. It will be of interest to determine if high conversions can be achieved at long reaction times and low pressure. Additional amounts of model compounds 2-naphthyl methyl phenyl ether and 2-naphthyl benzyl ether were synthesized. Purification of these compounds are now in progress.
Date: October 10, 1993
Partner: UNT Libraries Government Documents Department

Radiolysis of actinides and technetium in alkaline media

Description: The {gamma}-radiolysis of aerated alkaline aqueous solutions of Np(V), Np(VI), Pu(VI), Tc(IV), Tc(V), and TC(VII) was studied in the absence of additives and in the presence of CO{sub 3}{sup 2-}, NO{sub 3}{sup -}, NO{sub 2}{sup -}, EDTA, formate, and other organic compounds. The radiolytic reduction of Np(V), Np(VI), Pu(VI), and TC(VII) under different experimental conditions was examined in detail. The addition of EDTA, formate, and alcohols was found to considerably increase the radiation-chemical reduction yields. The formation of the Np(V) peroxo complex was observed in the {gamma}-radiolysis of alkaline aqueous solutions of Np (VI) in the presence of nitrate.
Date: July 10, 1996
Creator: Delegard, C. H.
Partner: UNT Libraries Government Documents Department

Wet processing of palladium for use in the tritium facility at Westinghouse, Savannah River, SC. Preparation of palladium using the Mound Muddy Water process

Description: Palladium used at Savannah River for tritium storage is currently obtained from a commercial source. In order to better understand the processes involved in preparing this material, Savannah River is supporting investigations into the chemical reactions used to synthesize this material and into the conditions necessary to produce palladium powder that meets their specifications. This better understanding may help to guarantee a continued reliable source for this material in the future. As part of this evaluation, a work-for-others contract between Westinghouse Savannah River Company and the Ames Laboratory Metallurgy and Ceramics Program was initiated. During FY98, the process for producing palladium powder developed in 1986 by Dan Grove of Mound Applied Technologies (USDOE) was studied to understand the processing conditions that lead to changes in morphology in the final product. This report details the results of this study of the Mound Muddy Water process, along with the results of a round-robin analysis of well-characterized palladium samples that was performed by Savannah River and Ames Laboratory. The Mound Muddy Water process is comprised of three basic wet chemical processes, palladium dissolution, neutralization, and precipitation, with a number of filtration steps to remove unwanted impurity precipitates.
Date: November 10, 1998
Creator: Baldwin, D.P. & Zamzow, D.S.
Partner: UNT Libraries Government Documents Department

Concrete sample point: 304 Concretion Facility

Description: This report contains information concerning the analysis of concretes for volatile organic compounds. Included are the raw data for these analysis and the quality control data, the standards data, and all of the accompanying chains-of-custody records and requests for special analysis.
Date: March 10, 1995
Creator: Rollison, M.D.
Partner: UNT Libraries Government Documents Department

LLNL Workshop on TEM of Pu

Description: On Sept. 10, 1996, LLNL hosted a workshop aimed at answering the question: Is it possible to carry out transmission electron microscopy (TEM) on plutonium metal in an electron microscope located outside the LLNL plutonium facility. The workshop focused on evaluation of a proposed plan for Pu microscopy both from a technical and environment, health, and safety point of view. After review and modification of the plan, workshop participants unanimously concluded that: (1) the technical plan is sound, (2) this technical plan, including a proposal for a new TEM, provides significant improvements and unique capabilities compared with the effort at LANL and is therefore complementary, (3) there is no significant environment, health, and safety obstacle to this plan.
Date: September 10, 1996
Creator: King, W.E.
Partner: UNT Libraries Government Documents Department

In situ vibrational spectroscopic investigation of C{sub 4} hydrocarbon selective oxidation over vanadium-phosphorus-oxide catalysts

Description: n-Butane selective oxidation over the VPO catalyst to maleic anhydride is the first and only commercialized process of light alkane selective oxidation. The mechanism of this reaction is still not well known despite over twenty years of extensive studies, which can partially be attributed to the extreme difficulties to characterize catalytic reactions real-time under typical reaction conditions. In situ spectroscopic characterization techniques such as Infrared spectroscopy and laser Raman spectroscopy were used in the current mechanistic investigations of n-butane oxidation over VPO catalysts. To identify the reaction intermediates, oxidation of n-butane, 1,3-butadiene and related oxygenates on the VPO catalyst were monitored using FTIR spectroscopy under transient conditions. n-Butane was found to adsorb on the VPO catalyst to form olefinic species, which were further oxidized to unsaturated, noncyclic carbonyl species. The open chain dicarbonyl species then experienced cycloaddition to form maleic anhydride. VPO catalyst phase transformations were investigated using in situ laser Raman spectroscopy. This report contains Chapter 1: General introduction; Chapter 2: Literature review; and Chapter 5: Conclusion and recommendations.
Date: May 10, 1999
Creator: Xue, Z.Y.
Partner: UNT Libraries Government Documents Department

Experimental study of SRAT/SME foaming by Illinois Institute of Technology

Description: This report summarizes the results of experiments performed by IIT in an effort to understand the fundamental science involved in the stable foam formation in the Defense Waste Processing Facility`s (DWPF`s) Chemical Processing Cell (CPC). The results of this testing will be confirmed in an experimental apparatus designed to be prototypic of DWPF CPC processing.
Date: November 10, 1997
Creator: Lambert, D.P. & Wasan, D.T.
Partner: UNT Libraries Government Documents Department

Absolute equation of state measurements of shocked liquid deuterium up to 200 GPa (2 Mbar)

Description: We present results of the first measurements of density, shock speed and particle speed in compressed liquid deuterium at pressures in excess in 1 Mbar. We have performed equation of state (EOS) measurements on the principal Hugoniot of liquid deuterium from 0.2 to 2 Mbar. We employ high-resolution radiography to simultaneously measure the compression of the sample. We are also attempting to measure the color temperature of the shocked D2. Key to this effort is the development and implementation of interferometric methods in order to carefully characterized the profile and steadiness of the shock and the level of preheat in the samples. These experiments allow us to differentiate between the accepted EOS model for D2 and a new model which included the effects of molecular dissociation on the EOS.
Date: June 10, 1997
Creator: Budil, K.S.; Da Silva, L.B. & Celliers, P
Partner: UNT Libraries Government Documents Department

Atom transfer and rearrangement reactions catalyzed by methyltrioxorhenium, MTO

Description: Methyltrioxorhenium (MTO) catalyzes the desulfurization of thiiranes by triphenylphosphine. Enormous enhancement in rate is observed when the catalyst is pretreated with hydrogen sulfide prior to the reaction. Using 2-mercaptomethylthiophenol as a ligand, the author synthesized several model complexes to study the mechanism of this reaction. With suitable model systems, they were able to show that the active catalyst is a Re(V) species. The reactions are highly stereospecific and very tolerant to functional groups. As part of the studies, he synthesized and crystallographically characterized the first examples of neutral terminal and bridging Re(V)sulfidocomplexes. Some of these complexes undergo fast oxygen atom transfer reactions with organic and inorganic oxidants. Studies on these model complexes led them to the discovery that MTO catalyzes the selective oxidation of thiols to disulfides. This report contains the Introduction; ``Chapter 6: Isomerization of Propargylic Alcohols to Enones and Enals Catalyzed by Methylrhenium Trioxide``; and Conclusions.
Date: May 10, 1999
Creator: Jacob, J.
Partner: UNT Libraries Government Documents Department

Unique applications of solvent removal in inductively coupled plasma mass spectrometry

Description: Inductively coupled plasma mass spectrometry (ICP-MS) is the technique of choice for rapid, high precision, semiquantitative elemental and isotopic analysis for over 70 elements. Less than 20 years after the first mass spectrum was obtained by ICP-MS, this technique has applications in clinical chemistry, geochemistry, the semiconductor industry, the nuclear industry, environmental chemistry, and forensic chemistry. The determination of many elements, though, by ICP-MS is complicated by spectral interferences from background species, interelement spectral overlaps, and polyatomic ions of matrix elements. The emphasis of this thesis is the unique applications of solvent removal using cryogenic and membrane desolvation. Chapter 1 is a general introduction providing background information concerning the need for these methods and some information about the methods themselves. Chapter 5 discusses general conclusions and general observations pertaining to this work. Chapters 2, 3, and 4 have been processed separately for inclusion on the database. Chapter 2 describes a method to screen urine samples for vanadium using cryogenic desolvation. Chapter 3 compares solvent removal by cryogenic and membrane desolvation. Chapter 4 describes the use of cool plasma conditions for the determination of potassium in the presence of excess sodium by ICP-MS.
Date: January 10, 1997
Creator: Minnich, M.
Partner: UNT Libraries Government Documents Department

Molten salt oxidation for treating low-level mixed wastes

Description: MS0 is a promising alternative to incineration for the treatment of a variety of organic wastes. Lawrence Livermore National Laboratory (LLNL) has prepared a facility (please see the photo attached) in which an integrated pilot-scale MS0 treatment system is being tested and demonstrated. The system consists of a MS0 vessel with a dedicated off-gas treatment system, a salt recycle system, feed preparation equipment, and a ceramic final waste forms immobilization system. The MSO/off-gas system has been operational since December 1997. The salt recycle system and the ceramic final forms immobilization became operational in May and August 1998, respectively. We have tested the MS0 facility with various organic feeds, including chlorinated solvents; tributyl phosphate/kerosene, PCB-contaminated waste oils & solvents, booties, plastic pellets, ion exchange resins, activated carbon, radioactive-spiked organics, and well-characterized low- level liquid mixed wastes. MS0 is a versatile technology for hazardous waste treatment and may be a solution to many waste disposal problems. In this paper we will present our operational experience with MS0 and also discuss its process capabilities as well as performance data with different feeds.
Date: December 10, 1998
Creator: Adamson, M G; Ford, T D; Foster, K G; Hipple, D L; Hopper, R W & Hsu, P C
Partner: UNT Libraries Government Documents Department

Annual Report 1998: Chemical Structure and Dynamics

Description: The Chemical Structure and Dynamics (CS&D) program is a major component of the William R. Wiley Environmental Molecular Sciences Labo- ratory (EMSL), developed by Pacific Northwest National Laboratory (PNNL) to provide a state-of- the-art collaborative facility for studies of chemical structure and dynamics. We respond to the need for a fundamental, molecular-level understanding of chemistry at a wide variety of environmentally important interfaces by (1) extending the experimental characterization and theoretical description of chemical reactions to encompass the effects of condensed media and interfaces; (2) developing a multidisciplinary capability for describing interracial chemical processes within which the new knowledge generated can be brought to bear on complex phenomena in envi- ronmental chemistry and in nuclear waste proc- essing and storage; and (3) developing state-of- the-art analytical methods for characterizing com- plex materials of the types found in stored wastes and contaminated soils, and for detecting and monitoring trace atmospheric species. Our program aims at achieving a quantitative understanding of chemical reactions at interfaces and, more generally, in condensed media, compa- rable to that currently available for gas-phase reactions. This understanding will form the basis for the development of a priori theories for pre- dicting macroscopic chemical behavior in con- densed and heterogeneous media, which will add significantly to the value of field-scale envi- ronmental models, predictions of short- and long- term nuclear waste storage stabilities, and other areas related to the primary missions of the U.S. Department of Energy (DOE).
Date: May 10, 1999
Creator: Colson, SD & McDowell, RS
Partner: UNT Libraries Government Documents Department

Three-body collision contributions to recombination and collision-induced dissociation. 1: Cross sections

Description: Atomic and molecular recombination and collision-induced dissociation (CID) reactions comprise two of the most fundamental types of chemical reactions. They are important in all gas phase chemistry; for example, about half of the 196 reactions identified as important in combustion chemistry are recombination or CID reactions. Many of the current chemical kinetics textbooks and kinetics papers treat atomic and molecular recombination and CID as occurring only via sequences of two-body collisions. Actually, there is considerable evidence from experiment and classical trajectory calculations for contributions by true three-body collisions to the recombination of atomic and diatomic radicals, and that evidence is reviewed. Then, an approximate quantum method treating both two-body and three-body collisions simultaneously and on equal footing is used to calculate cross sections for the reaction Ne{sub 2} + H {rightleftharpoons} Ne + Ne + H. The results provide clear quantum evidence that direct three-body collisions do contribute significantly to recombination and CID.
Date: April 10, 1998
Creator: Pack, R. T.; Walker, R. B. & Kendrick, B. K.
Partner: UNT Libraries Government Documents Department

Decomposition of Tetraphenylborate In Tank 48H

Description: This report provides a qualitative and semiquantitative description of the chemical reaction that decomposed the excess sodium tetraphenylborate in Tank 48H during November and December 1995.
Date: May 10, 1996
Creator: Barnes, M.J.; Walker, D.D.; Crawford, C.L.; Swingle, R.S.; Peterson, R.A.; Hay, M.S. et al.
Partner: UNT Libraries Government Documents Department

Resonance ionization spectroscopy of molecules, clusters, and ions. Continuation proposal and annual technical progress report

Description: Supersonic beam studies of the dimer of the aromatic molecule fluorene reveal both excitonic and excimer properties. The high resolution spectra obtained for the cold clusters suggests that it will be possible to elucidate the coupling between these types of states. The accumulating evidence indicates that both types of states occur generally for aromatic clusters. Their relative contributions to the spectra are not currently understood. This problem is the emphasis of the ongoing investigations. Future work will address the intermolecular potential functions of these species in increasing detail.
Date: July 10, 1992
Creator: Wessel, J.
Partner: UNT Libraries Government Documents Department

Solvation Effects in Self-Assembled Systems

Description: Many types of self-assembly can be found in nature. They include crystallization, the formation of micelles, and the folding of proteins. Recently there has been much interest in pursuing nano-to-microscopically engineered materials by way of self-assembly on imprinted or templated surfaces. In all of these diverse cases, wetting plays a critical role in the assembly process. Wetting involves the interactions of the substrate or amphiphilic molecule or macromolecule with a solvent. In many self-assembled systems we find that the critical feature of the system is a substrate! or macromolecule with a both hydrophilic and hydrophobic nature. In this paper we discuss the wetting properties of a striped surface where the stripes represent alternating chemical characteristics. We show how the chemical heterogeneity affects the wetting properties of the surface (e.g. the static contact angle), and discuss the length limitations on the soft lithography approach. In this paper, the wetting of a chemically heterogeneous surface is studied using a nonlocal Density Functional Theory (DFT). The results for the heterogeneous surface model we discuss have immediate implications for soft-lithography by self-assembly. It also lends fundamental insight into the mechanisms controlling self-assembly of macromolecules. We present the results of nonlocal 2D DFT calculations on the wetting properties of chemically heterogeneous surfaces. These calculations showed complex density distributions and phase behavior as a result of the heterogeneity. The location of the wetting transition are found to be strongly dependent on the extent and strength of the heterogeneity, and complete wetting was suppressed altogether if the hydrophobic parts of the surface were large enough. In these cases, the condensed nanophase may crystallize if the hydrophilic surface-fluid interactions are strong enough. By exploring the phase space including strength of hydrophilic interactions and extent of chemical heterogeneity, an operational phase diagram was established that could be used for ...
Date: November 10, 1998
Creator: Frink, L.J.D.
Partner: UNT Libraries Government Documents Department

Steam pretreatment for coal liquefaction. [Monthly report], December 1, 1993--December 31, 1993

Description: The effect of exposing coal sample no. 31 which was pretreated in steam to air was tested this month. Significant differences from yields obtained with the previously used sample is observed. Consequently, averaging yields from the two samples is not appropriate and the pattern of behavior of each set must be determined separately. Further work will be done using new Illinois No.6 coal sample. Analysis of the products of aquathermolysis of {beta}benzylnaphthyl ether in presence of liquid water were completed. Major product is naphthol. Minor fraction was determined to be unreacted starting material. The purity check of the sample of a-naphthylmethyl phenyl ether was completed. Studies of this model compound will be performed next month.
Date: January 10, 1993
Partner: UNT Libraries Government Documents Department

Steam pretreatment for coal liquefaction. [Monthly report], August 1, 1993--August 31, 1993

Description: Rapid heating liquefaction of steam pretreated Illinois No.6 coal mixed with 13X zeolite was carried out this month. The pores of this zeolite retain pyridine during drying, but not enough to account for the low apparent yield of pyridine extract. Soxhlet extraction analysis of the product showed a significantly lower oil yield compared with 5A zeolite. This might be caused by retention of tetralin in 13x zeolite pores. Tetralin retention will be determined subsequently. A test of 4A zeolite is planned for next month. Aquathermolysis of model compound {beta}-benzylnaphthyl ether was carried out this month at high pressure (liquid water conditions). Analysis of the recovered products are now in progress.
Date: September 10, 1993
Partner: UNT Libraries Government Documents Department

Investigation of microscale electromechanical technologies for continuous monitoring. Final report

Description: Efforts are under way worldwide to integrate electronic and mechanical components on solid state devices to perform the functions of traditional sensors at the micro-scale. For example, chemical sensors have been envisioned that involve pumping air or liquid samples at small volumetric flow rates over long periods of time for continuous monitoring of environments. The mechanical components on these devices are fabricated into monolithic silicon or other solid state media. These types of devices, if proven successfully, would offer new capabilities for remote monitoring at very small size, weight, and power consumption. When coupled with micro-scale monolithic communications components, the technical option could exist for extremely small remote monitoring devices. Heretofore, little effort has been invested at the Laboratory in examining specific design problems that could capitalize on the emerging component technologies under development at both large and small computer and electronics firms worldwide. Our program involved conceptual designs and selected prototype manufacturing of three different types of micro-scale sensors that could be applied to problems in the nonproliferation mission areas.
Date: February 10, 1995
Creator: Finucane, R.; Ruggiero, A. & Sheem, S.
Partner: UNT Libraries Government Documents Department