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in subjects: "Structural Chemical Analysis"

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Surfactant development for enhanced oil recovery. First quarterly report, [October 1993--January 1994]

This report covers the period from October, 1993 to January, 1994. It summarizes the activities on the grant to develop novel surfactants for enhanced oil recovery, and represents the first quarterly report for the project. During the period covered by this report, considerable effort was spent in arrangements for procuring equipment, chemicals and in educating students about the substance of the project. Unfortunately, the major equipment order to fully implement the project have not yet been … more

Date: February 25, 1994

Creator: Iwunze, M. O.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

ALCHEMI of Fe-doped B2-ordered NiAl alloys with different doping levels

The ALCHEMI technique yields exact expressions for best-fit parameters in terms of ionization localization constants and site distributions of 3 elements distributed over two sublattices. In this paper, a graphical plotting technique is applied to Fe-doped NiAl B2-ordered alloys Ni{sub 0.5-x}Fe{sub x}Al{sub 0.5}, with x=0.02 or 0.10. The thin foil samples were examined in an electron microscope with an x-ray spectrometer.

Date: September 1, 1994

Creator: Anderson, I. M.; Bentley, J. & Duncan, A. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Two dimensional NMR and NMR relaxation studies of coal structure. Progress report, January 1, 1993--March 31, 1993

This report covers the progress made on the title project for the project period. Four major areas of inquiry are being pursued. Advanced solid state NMR methods are being developed to assay the distribution of the various important functional groups that determine the reactivity of coals. Special attention is being paid to methods that are compatible with the very high magic angle sample spinning rates needed for operation at the high magnetic field strengths available today. Polarization inve… more

Date: July 1, 1993

Creator: Zilm, K. W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Structure of Liquid Trivalent Salts

Total neutron scattering measurements have been made on three trivalent molten salts: InCl{sub 3} (605C), BiCl{sub 3}(300C) and BiI{sub 3} (420C). Results are discussed in the general context of ordering, bonding and macroscopic properties of trivalent molten salts.

Date: April 1, 1993

Creator: Price, D. L.; Saboungi, M. L.; Howells, W. S. & Tosi, M. P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Genome analysis of Elusimicrobium minutum, the first cultivated representative of the Elusimicrobia phylum (formerly Termite Group 1)

The candidate phylum Termite group 1 (TG1), is regularly 1 encountered in termite hindguts but is present also in many other habitats. Here we report the complete genome sequence (1.64 Mbp) of Elusimicrobium minutum strain Pei191{sup T}, the first cultured representative of the TG1 phylum. We reconstructed the metabolism of this strictly anaerobic bacterium isolated from a beetle larva gut and discuss the findings in light of physiological data. E. minutum has all genes required for uptake and … more

Date: February 1, 2009

Creator: Herlemann, D. P. R.; Geissinger, O.; Ikeda-Ohtsubo, W.; Kunin, V.; Sun, H.; Lapidus, A. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

A probe-based mapping strategy for DNA sequencing with mobile primers

Research on DNA sequencing continued. The specific areas of research targeted for the period of this Progress Report included three general phases: (1) optimization of probe-mapping by both the development of new transposons and the design of stream-lined methods for mapping; (2) application of transposon-based methods to larger plasmids and cosmids; and (3) initiation of PCR-based applications of transposons.

Date: January 1, 1991

Creator: Strausbaugh, L. D. & Berg, C. M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Mechanisms for radiation damage in DNA. Final report, June 1, 1986--August 31, 1996

Over the last 10 years significant advances have been made impacting the understanding of radiation damage to DNA. The principal objective of this work was the elucidation of the fundamental mechanisms of radiation damage to DNA through the direct and indirect effects. Recently the work concentrated on the direct effect of radiation damage on DNA. The objective was to elucidate the ultimate radiation chemical damage to DNA arising from the direct effect. In this effort the focus was on the appl… more

Date: August 1, 1996

Creator: Sevilla, M. D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Global continuation for distance geometry problems

Distance geometry problems arise in the interpretation of NMR data and in the determination of protein structure. The authors formulate the distance geometry problem as a global minimization problem with special structure, and show the global smoothing techniques and a continuation approach for global optimization can be used to determine solutions of distance geometry problems with a nearly 100% probability of success.

Date: March 1, 1995

Creator: More, J. J. & Wu, Zhijun

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Sequential low-temperature depolymerization and liquefaction of US coals. Progress report No. 1, October 1--December 31, 1986

Results obtained in the studies with BS(IL) coal as feed can be summarized as follows: (1) The low-temperature depolymerization - liquefaction procedure, summarized in Figure 1, is easily adaptable and applicable to a high-sulfur, Burning Star (Illinois No. 6) coal sample. The final product obtained consists of a fully desulfurized, light hydrocarbon oil. (2)Suitable processing conditions for each step of the stepwise depolymerization - liquefaction of the above coal were determined. (3)Direct … more

Date: January 1, 1987

Creator: Shabtai, J. S. & Wiser, W. H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Structural ordering in liquid K-Te alloys

Neutron diffraction from molten K{sub x}Te{sub 1{minus}x} is reported for x = 0.12 and x = 0.50 semiconducting alloys. The measured radial distribution functions (rdf) demonstrate the persistence of covalently bonded tellurium in the liquid. The rdf of the liquid K{sub 0.12}Te{sub 0.88}, which is dominated by the Te-Te contribution, is remarkably similar to that of pure liquid tellurium, the notable exception being that the nearest neighbor peak is largely resolved and found to have a coordinat… more

Date: March 1, 1994

Creator: Fortner, J.; Saboungi, M. L. & Enderby, J. E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Internal energy effects on the solvation and reactivity of multiply charged biomolecules for electrospray ionization mass spectroscopy

Mild (capillary) interface conditions which do not completely desolvate the ions of proteins in electrospray ionization mass spectrometry (ESI-MS) may be required to probe the higher order structures and weak associations. For the small protein bovine ubiquitin, two ion distributions (unsolvated ions and unresolved solvated ions) were observed. The resolvable solvation for leucine-enkephalin with methanol and water shows that the use of countercurrent N{sub 2} flow at the capillary affects the … more

Date: June 1, 1992

Creator: Light-Wahl, K. J.; Winger, B. E.; Rockwood, A. L. & Smith, R. D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

GATA: A graphic alignment tool for comparative sequenceanalysis

Several problems exist with current methods used to align DNA sequences for comparative sequence analysis. Most dynamic programming algorithms assume that conserved sequence elements are collinear. This assumption appears valid when comparing orthologous protein coding sequences. Functional constraints on proteins provide strong selective pressure against sequence inversions, and minimize sequence duplications and feature shuffling. For non-coding sequences this collinearity assumption is often… more

Date: January 1, 2005

Creator: Nix, David A. & Eisen, Michael B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Scanning transmission x-ray microscopy: A new ``looking glass`` into coal chemical structure

This paper reports the use of scanning transmission x-ray microscopy to spatially map the chemistry of aromatic and aliphatic carbon functionalities in coal to a resolution of less than 0.1 {mu}m. Localized x-ray absorption spectroscopy recorded at the carbon K absorption edge was also used to facilitate analysis of variations in fundamental chemistry at maceral interfaces and within maceral boundaries.

Date: February 1, 1994

Creator: Botto, R. E. & Cody, G. D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

CAMD studies of coal structure and coal liquefaction

The macromolecular structure of coal is essential to understand the mechanisms occurring during coal liquefaction. Many attempts to model coal structure can be found in the literature. More specifically for high volatile bituminous coal, the subject of interest the most commonly quoted models are the models of Given, Wiser, Solomon, and Shinn. In past work, the authors`s have used computer-aided molecular design (CAMD) to develop three-dimensional representations for the above coal models. The … more

Date: October 1, 1994

Creator: Faulon, J. L. & Carlson, G. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Industrial applications of accelerator-based infrared sources: Analysis using infrared microspectroscopy

Infrared Microspectroscopy, using a globar source, is now widely employed in the industrial environment, for the analysis of various materials. Since synchrotron radiation is a much brighter source, an enhancement of an order of magnitude in lateral resolution can be achieved. Thus, the combination of IR microspectroscopy and synchrotron radiation provides a powerful tool enabling sample regions only few microns size to be studied. This opens up the potential for analyzing small particles. Some… more

Date: September 1, 1997

Creator: Bantignies, J.L.; Fuchs, G.; Wilhelm, C.; Carr, G.L. & Dumas, P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Surface properties of photo-oxidized bituminous coals. Technical progress report, January--March 1996

During this report period, a vitrinite concentrate from the mvb Splash Dam seam (DECS-30) was prepared and analyzed. Results show that the concentrate was 91 vol % vitrinite and that the sample has been adequately protected from oxidation under refrigerated storage in argon. The 9% level of contamination within the vitrinite resulted from the extreme friability of the coal and to the dispersion of fine grains of semifusinite and micrinite. Polished blocks containing vitrain bands that were prep… more

Date: December 31, 1996

Creator: Mitchell, G.; Davis, A. & Chander, S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Temperature Effects on Chemical Structure and Motion in Coal. Quarterly Report, April--June, 1995

As described in previous reports, the effects of moderate temperatures (up to 230 C) is to increase molecular/macromolecular mobility in coals, as determined by {sup 1}H CRAMPS (Combined Rotation And Multiple Pulse Spectroscopy) measurements, especially dipolar-dephasing experiments. Pyridine-saturated coals have also been studied with the same kinds of NMR experiments. The author found that thermal activation and solvent saturation promote the molecular mobility of coals in quite different way… more

Date: June 30, 1995

Creator: Maciel, G.E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Organosulphur compounds in coals as determined by reaction with Raney nickel and microscale pyrolysis techniques. Quarterly report, 1 July 1995--31 October 1995

As well as studying coal samples from Oklahoma and Missouri States, we have now completed the preliminary part of a study of a well known high organosulphur containing coal, Illinois No. 6. As a number of other research groups have used Illinois No. 6 for study, we thought it wise to also analyse this coal for comparison of our method with existing data reported in the literature. To date, analyses of the aliphatic fractions of the free maltene components and the aliphatic hydrocarbons isolated… more

Date: December 31, 1995

Creator: Stalker, Linda & Philp, R. Paul

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Molecular accessibility in oxidized and dried coals. Quarterly report

The objective of this research project is to determine the molecular and structural changes that occur in swelled coal as a result of oxidation and moisture los both in the presence and absence of light using our newly developed EPR spin probe method. The proposed study will make it possible to deduce the molecular accessibility distribution swelled, {ital oxidized} APCS coal for each rank as a function of (1) size (up to 6 nm) and shape, (2) the relative acidic/basic reactive site distribution… more

Date: December 1, 1995

Creator: Kispert, L. D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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(Multiplex mapping of human cDNAs)

J. Craig Venter, National Institute of Neurological Disorders and Stroke, has begun to identify genes expressed in the human brain by partially sequences cDNA clones. We are collaborating with the Venter group and using their sequence data to develop methods for rapid localization of newly identified cDNAs to human chromosomes. We are applying the ABI automated DNA sequencer to the analysis of fluorescently-tagged PCR products for assigning sequences to individual human chromosomes. The steps i… more

Date: January 1, 1991

Creator: Nierman, W.C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Advanced Nmr Approaches in the Characterization of Coal. [Quarterly] Report No. 8

The paper submitted earlier on the use of (bicyclo[3.2.1]4pyrrolidino-N-methyl-octan-8-one triflate) ({sup 13}CO-123) as a {sup 13}C intensity standard was accepted for publication. Subsequently, {sup 13}CO-321 was used in this manner for quantitative {sup 13}C CP-MAS NMR analysis (including spin counting) of Argonne Premium coals. The cross-polarization time constants, T{sub CH}, and the rotating-frame proton spin-lattice relaxation times, T{sub 1p}{sup H}, were determined for each major peak … more

Date: December 31, 1992

Creator: Maciel, G. E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Neutron diffraction study of aluminum chloride imidazolium chloride molten salts

The structure of molten mixtures of (AlCl{sub 3}){sub x}(1-ethyl-3-methylimidazolium chloride){sub 1-x} was investigated by neutron diffraction techniques for x=0.46, 0.50, 0.60 and 0.67. Results derived from earlier ab initio molecular orbital (6-31G* basis set) computations for AlCl{sub 4}{sup {minus}}, Al{sub 2}Cl{sub 7}{sup {minus}}, and EMI{sup +} were used to calculate the diffraction patterns; the calculated contributions of each species are thus obtained and overall results are in good … more

Date: February 1, 1994

Creator: Takahashi, S.; Saboungi, M. L.; Suzuya, K. & Koura, N.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Characterization of a Pu-Bearing Zirconolite-Rich Synroc

A titanate-based ceramic waste form, rich in phases structurally related to zirconolite (CaZrTi{sub 2}O{sub 7}), is being developed as a possible method for immobilizing excess plutonium from dismantled nuclear weapons. As part of this program, Lawrence Livermore National Laboratory (LLNL) produced several ceramics that were then characterized at Argonne National Laboratory (ANL). The plutonium- loaded ceramic was found to contain a Pu-Gd zirconolite phase but also contained plutonium titanates… more

Date: December 31, 1996

Creator: Buck, E. C.; Ebbinghaus, B.; Bakel, A. J. & Bates, J. K.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Organosulfur compounds in coals as determined by reaction with Raney nickel and microscale pyrolysis techniques. Quarterly report, July--September 1996

Since the last quarterly report the authors have continued with the detailed analyses of the coal degradation products by gas chromatography-mass spectrometry (GCMS). This is a very time consuming process since the degradation products are very complex, even though they have been separated into saturate and aromatic fractions. Most of the efforts are centering on the saturate fractions at this time. Furthermore it is necessary to make detailed comparisons between the deuterated and non-deuterat… more

Date: December 31, 1998

Creator: Stalker, L. & Philp, P.

Item Type: Report

Partner: UNT Libraries Government Documents Department