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Chemometric Analysis of Nuclear Magnetic Resonance Spectroscopy Data

Description: Chemometric analysis of nuclear magnetic resonance (NMR) spectroscopy has increased dramatically in recent years. A variety of different chemometric techniques have been applied to a wide range of problems in food, agricultural, medical, process and industrial systems. This article gives a brief review of chemometric analysis of NMR spectral data, including a summary of the types of mixtures and experiments analyzed with chemometric techniques. Common experimental problems encountered during th… more
Date: July 20, 2000
Creator: ALAM,TODD M. & ALAM,M. KATHLEEN
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Magnetic Field Measurements by Nuclear Resonance

Description: Abstract: The purpose of this report is to outline the work done at the Radiation Laboratory toward the development of a magnetic field measuring device using the phenomenon of nuclear resonance. While the work described here is far from complete, it has served to indicate the limitations of the method as well as some of its possibilities. For reasons which will become apparent, the project is being discontinued. It is hoped that this report will serve as a starting point should the work be… more
Date: August 20, 1948
Creator: Kafitz, Peter
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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/sup 35/Cl and /sup 81/Br nuclear magnetic resonance studies of carbonic anhydrase

Description: /sup 35/Cl NMR studies substantiated the binding of Cl/sup -/ to the Zn(II) of carbonic anhydrase. Zinc-free carbonic anhydrase was prepared and it exhibited essentially no effect on the Cl/sup -/ line width. The net Cl/sup -/ line width increased with temperature. /sup 81/Br NMR was quite similar to /sup 35/Cl in that its relaxation is dominated by quadrupolar interactions.
Date: February 1, 1979
Creator: Ward, R.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Molecular structure and motion in zero field magnetic resonance

Description: Zero field magnetic resonance is well suited for the determination of molecular structure and the study of motion in disordered materials. Experiments performed in zero applied magnetic field avoid the anisotropic broadening in high field nuclear magnetic resonance (NMR) experiments. As a result, molecular structure and subtle effects of motion are more readily observed.
Date: October 1, 1989
Creator: Jarvie, T.P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nuclear magnetic resonance wide-line study of hydrogen in the yttrium-yttrium dihydride system

Description: The /sup 1/H nuclear magnetic resonance was studied in the yttrium-hydrogen system YH/sub x/ in the composition range 0.20 less than or equal to x less than or equal to 1.98 and temperature range 77 K less than or equal to T less than or equal to 490/sup 0/K. Both ..cap alpha..- and ..beta..-phases of YH/sub x/ were investigated in polycrystalline (powdered) specimens. Rigid lattice proton resonance second moments were obtained for both ..cap alpha..- and ..beta..-phase samples. Analysis of the… more
Date: March 1, 1980
Creator: Anderson, D. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Applications of pulsed nuclear magnetic resonance to chemistry: multiple-pulse NMR, cross polarization, magic-angle spinning annd instrumental design

Description: Pulsed Nuclear Magnetic Resonance (NMR) has been applied to: (1) Measurements of the prinicpal components of the proton shielding tensors of the hydrides of zirconium chloride and zirconium bromide. Multiple-Pulse techniques have been used to remove static homonuclear dipolar coupling. The anisotropies and isotropic shifts of these tensors have been used to infer the possible locations of the hydrogen within the sandwich-like layers of these unusual compounds. (2) Studies of the oscillatory tra… more
Date: July 1, 1979
Creator: Murphy, P.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Inhibition of retrogressive reactions in coal/petroleum co-processing

Description: The overall objective of this project is to develop a fundamental understanding of the reactions occurring at the onset of coke formation during the CO-processing of coals with action of chemical components, or groups of components, in coals and petroleum feedstocks to quantify and rank the effects of these components in retarding or enhancement of coke formation. The work involves bench scale reactions in microautoclaves, supplemented by studies of the carbonaceous residues by such techniques … more
Date: May 1, 1992
Creator: Schobert, H. H. & Tomic, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Characterization of western coals and coal macerals by solid-state nuclear magnetic resonance spectroscopy. Progress report, August 1, 1981-January 31, 1982

Description: Two bituminous coals were selected on the basis of petrographic analysis as having high concentrations of vitrinite, inertinite and liptinite. These coal samples were ground up to about 10-3 ..mu..m, treated with HCl and HF to remove the mineral matter, and the macerals were separated by density gradient centrifugation. Structural features of the three different macerals were obtained by NMR analysis based on conventional CP/MAS and multiple pulse multi-dimensional /sup 13/C NMR spectroscopy. R… more
Date: January 1, 1982
Creator: Pugmire, R. J. & Grant, D. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Dynamic nuclear-polarization studies of paramagnetic species in solution

Description: Dynamic Nuclear Polarization (DNP) was used to measure the electron spin lattice relaxation times, T/sub 1/, of transition metal ions in aqueous solution. Saturation which is induced in the electron spin system is transferred to the solvent proton spins by dipole-dipole interactions. The change in the polarization of the proton spins is much larger than it is in the electron spins. The change in proton polarization is easily measured by proton Nuclear Magnetic Resonance (NMR). In one experiment… more
Date: July 1, 1982
Creator: Glad, W.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Determination of Deuterium and Tritium in Effluent Wastewater by Pulsed Nuclear Magnetic Resonance Spectroscopy

Description: A pulsed nuclear magnetic resonance (NMR) procedure was developed for the quantitative determination of deuterium and tritium in radioactive, effluent, wastewater to aid in the design of an efficient combined electrolytic/catalytic exchange system for the recovery of these hydrogen isotopes. The deuterium and tritium NMR signals were observed at 9.210 and 45.7 MHz, respectively. Ten different effluent water samples were analyzed for deuterium and tritium to establish base-line data for the prep… more
Date: April 1, 1985
Creator: Attalla, A. & Birkbeck, J. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Two dimensional NMR and NMR relaxation studies on coal structure. Final report, September 13, 1994--January 31, 1995

Description: This research program focused on developing new solids nuclear magnetic resonance (NMR) techniques for improved analysis of coal structure. Most work has been concentrated on the development of spectral editing NMR methods for solids.
Date: October 1, 1995
Creator: Zilm, K.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Polarization phenomena in projectile fragmentation process

Description: The nuclear spin polarization of beta-emitting fragments {sup 37}K and {sup 39} Ca has been measured at around the grazing angle of the {sup 40}Ca + Au collision at 106 MeV/u. Momentum dependence of the observed fragment polarization supports the idea that the origin of the polarization is the orbital angular momentum held by the fragment part of the projectile before the collision takes place. The sizable polarization of about 5% that was observed for the fragments will be a powerful tool for … more
Date: March 1, 1992
Creator: Matsuta, K.; Ozawa, A.; Nojiri, Y.; Minamisono, T.; Fukuda, M.; Kitagawa, A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Solvent Tailoring in Coal Liquefaction. Quarterly Report, October 1983-December 1983

Description: The contribution of transferable hydrogen in coal-derived solvents to coal conversion was investigated in a two-step process. Initially, the amount of transferable hydrogen in the coal-derived solvents was analyzed by spectroscopic methods and by catalytic dehydrogenation. The spectroscopic methods included carbon magnetic resonance, proton magnetic resonance as well as a combination of these two methods. Three of the methods gave nearly equivalent quantities for the amount of transferable hydr… more
Date: July 1, 1983
Creator: Tarrer, A. R.; Curtis, C. W.; Guin, J. A. & Williams, D. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Copper and oxygen NMR studies on the magnetic properties of YBa sub 2 Cu sub 3 O sub 7-y

Description: Microscopic magnetic properties of the CuO{sub 2} layers in YBa{sub 2}Cu{sub 3}O{sub 7-y} have been investigated from Cu and O NMR experiments on the y{approx equal}0 (T{sub c}=92K) and y=0.37 (T{sub c}=62K) materials. The Knight shift at the planar Cu and the planar oxygen sites are found to be proportional to a common spin susceptibility {chi}{sub s} which depends on temperature and oxygen-content, strongly supporting a single component spin model for the CuO{sub 2} planes. In the y=0.37 mate… more
Date: January 1, 1989
Creator: Takigawa, Masashi.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development and initial characterization of a nuclear magnetic resonance dosimetry system

Description: A novel high dose radiation dosimeter was developed employing NMR spectroscopic quantitation of the radiolytic products of methanol. Chemical shifts of product resonances relative to the solvent allow quantification using NMR techniques. Due to expected dynamic range limitations of NMR instrumentation, deuterated methanol is used with a presaturation suppression sequence to reduce the solvent proton signals. Methanol's {sup 13}C-coupled proton resonances is used as an internal reference to norm… more
Date: January 1, 1990
Creator: Thomasson, D.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Mound Laboratory activities in chemical and physical research: July--December 1976. [Isotope separation; metal hydride research, separation chemistry and separation research]

Description: The status of the following programs is reported: isotope separation of carbon, argon, helium, krypton, neon, xenon, oxygen, and sulfur; metal hydride research; separation chemistry; and separation research. (LK)
Date: May 4, 1977
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of Bromine-77 from the LAMPF facility

Description: The objective of the work is to conduct the necessary studies required to evaluate the efficacy, potential benefit and role of bromine-77 labelled steroids in the detection and evaluation of treatment for hormone-dependent tumors. The synthetic goals of 1982-3 included the synthesis estradiol derivatives which were radiohalogenated in the A- or C-ring with bromine-77 or bromine-82. Estradiol derivatives in which the radiohalogen was incorporated into the C-ring were prepared and purified with h… more
Date: December 3, 1982
Creator: Mettler, F.A. & Hylarides, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Synthesis and stability of liquid molecular DT

Description: Regular equimolar deuterium-tritium is a mixture of 25 mol% T/sub 2/-50% DT-25% D/sub 2/. We have synthesized molecular DT of greater purity by the reaction LiT + CH/sub 3/OD ..-->.. DT + LiOCH/sub 3/, run at 243/degree/K. With both the alcohol and reactor-to-cryostat transfer lines at room temperature, we obtain 88 mol% DT purity. By cooling the alcohol and holding the transfer lines at 80/degree/K, the yield rose to 95% DT. The DT disproportionated to D/sub 2/ and T/sub 2/ with a 1e time cons… more
Date: May 1, 1988
Creator: Souers, P. C.; Fearon, E. M.; Garza, R. G.; Friffith, C. M.; Mayhugh, S. R.; Mapoles, E. R. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Biology and Medicine Division annual report, 1982-1983

Description: This annual report presents brief summaries of research activities during 1982 to 1983. Program activities have been individually entered into EDB. They include research medicine, radiosurgery, environmental physiology, radiation biophysics, and structural biophysics. (ACR)
Date: April 1, 1984
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effects of processing conditions on the reliability of cross-linked polyethylene cable insulation. Progress report

Description: Crystallization and morphology were investigated in cross-linked PE. /sup 13/C NMR was used to quantify the cross-links. Production of cable is being studied. Dielectric constant and loss of cross-linked PE are being measured. (DLC)
Date: March 1, 1981
Creator: Phillips, P.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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