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Dissertations / Theses on the topic '³¹P nuclear magnetic resonance (NMR) spectroscopy'

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Published: 10 December 2022

Last updated: 28 January 2023

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1

Schachter, Joyce. "Application of surface coils to in-vivo studies using ³¹P-NMR spectroscopy." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/24914.

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The work described in this thesis is divided into two parts: testing and evaluation of some surface coils, and application of the surface coils to in-vivo studies. In particular, the localization properties of surface coils were examined and optimized using the highest performance coil geometry and wire. Application of the surface coil technique to in-vivo studies involved measuring changes in metabolic status of muscle and brain tissue in rats using ³¹P spectroscopy. The properties of surface coils have been studied by evaluating their excitation patterns with ¹H and ³¹P NMR spectroscopy. Surface coils, manufactured in different sizes, geometries, and materials were tested for Q factors, signal-to-noise ratios, and pulse widths required for excitation of the sample. A silver plating on the copper wire used to fabricate the surface coils was found to increase the Q and signal-to-noise of the coil. Examination of the excitation patterns of the surface coils with point samples characterized the B₁ field of the coils as decreasing axially and radially from the coil. Calculations of the magnitude of the B₁ field reveal that its dome-like shape extends to approximately one coil radius above the surface coil. It was found that samples lying outside the domain of this "sensitive volume" did not contribute to a spectrum. These data were all correlated and the "0.9" silver plated coil was deemed to be the most efficient coil with which to pursue further in-vivo studies. In-vivo ³¹P studies of rat tissues were preceded by in-vitro spectral measurements of various metabolites at physiological concentrations. These standards were used to aid in the identification of resonances in the in-vivo spectra. Metabolic changes such as artificially induced ischemia in muscle, deceased brain, and artificially induced brain dementia were compared with "normal" ³¹P spectra of anaesthetized rat tissues. It was found that oxygen deprivation is readily observed with this technique whereas the preparation of brain dementia cannot be diagnosed with ³¹P NMR spectroscopy.
Science, Faculty of
Chemistry, Department of
Graduate

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2

Sneddon, Scott. "Characterisation of inorganic materials using solid-state NMR spectroscopy." Thesis, University of St Andrews, 2016. http://hdl.handle.net/10023/8239.

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This thesis uses solid-state nuclear magnetic resonance (NMR) spectroscopy and density functional theory (DFT) calculations to study local structure and disorder in inorganic materials. Initial work concerns microporous aluminophosphate frameworks, where the importance of semi-empirical dispersion correction (SEDC) schemes in structural optimisation using DFT is evaluated. These schemes provide structures in better agreement with experimental diffraction measurements, but very similar NMR parameters are obtained for any structures where the atomic coordinates are optimised, owing to the similarity of the local geometry. The ³¹P anisotropic shielding parameters (Ω and κ) are then measured using amplified PASS experiments, but there appears to be no strong correlation of these with any single geometrical parameter. In subsequent work, a range of zeolitic imidazolate frameworks (ZIFs) are investigated. Assignment of ¹³C and ¹⁵N NMR spectra, and measurement of the anisotropic NMR parameters, enabled the number and type of linkers present to be determined. For ¹⁵N, differences in Ω may provide information on the framework topology. While ⁶⁷Zn measurements are experimentally challenging and periodic DFT calculations are currently unreliable, calculations on small model clusters provide good agreement with experiment and indicate that ⁶⁷Zn NMR spectra are sensitive to the local structure. Finally, a series of pyrochlore-based ceramics (Y₂Hf₂₋ₓSnₓO₇) is investigated. A phase transformation from pyrochlore to a disordered defect fluorite phase is predicted, but ⁸⁹Y and ¹¹⁹Sn NMR reveal that rather than a solid solution, a significant two-phase region is present, with a maximum of ~12% Hf incorporated into the pyrochlore phase. The use of ¹⁷O NMR to provide insight into the local structure and disorder in these materials is also investigated. Once the different T₁ relaxation and nutation behaviour is considered it is shown that quantitative ¹⁷O enrichment of Y₂Sn₂O₇ is possible, and that ¹⁷O does offer a promising future tool for study.

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3

Wu, Xi-Li. "New techniques in nuclear magnetic resonance spectroscopy." Thesis, University of Cambridge, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385872.

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4

Barker, P. B. "New techniques in nuclear magnetic resonance." Thesis, University of Oxford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375213.

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5

Stonehouse, Jonathan. "New techniques in NMR spectroscopy." Thesis, University of Cambridge, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.360628.

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6

Talagala, Sardha Lalith. "Aspects of NMR imaging and in vivo spectroscopy." Thesis, University of British Columbia, 1986. http://hdl.handle.net/2429/27550.

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The work described in this thesis deals mainly with aspects related to two- and three-dimensional NMR imaging. A detailed discussion on frequency-selective excitation using amplitude modulated rf pulses in relation to slice selection in NMR imaging has been presented. This includes the analysis and implementation of the method as well as illustrative experimental results. Several radiofrequency probe designs suitable for high field NMR imaging have been experimentally evaluated and their modification and construction are also described. The comparative results obtained indicate the merits and demerits of different designs and provide necessary guidelines for selecting the most suitable design depending on the application. Practical aspects of two- and three-dimensional imaging have been discussed and NMR images of several intact systems have been presented. Experimental methods which enable slice selection in the presence of chemically shifted species and two-dimensional chemical shift resolved imaging have "been described and illustrated using phantoms. The use of three-dimensional chemical shift resolved imaging as a potential method to map the pH and temperature distribution within an object has also been demonstrated. A preliminary investigation of the application of ³¹P NMR spectroscopy to study the biochemical transformations of the rat kidney during periods of ischemia and reperfusion has been presented.
Science, Faculty of
Chemistry, Department of
Graduate

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7

Almond, Graham G. "A nuclear magnetic resonance study of hydrous layer silicates." Thesis, Durham University, 1995. http://etheses.dur.ac.uk/5096/.

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This is a study of five silicates, namely makatite, kanemite, octosilicate, magadiite and kenyaite. The silicates have been analysed using a range of techniques, principally solid-state NMR spectroscopy. High-quality (^29)Si NMR spectra have been obtained for samples of all five layered sodium polysilicate hydrates. Amongst other findings, these have revealed four crystallographically distinct sites in makatite and a Q(^4):Q(^4) site ratio in kenyaite of ca. 5. Proton MAS NMR studies can produce well-resolved spectra, particularly for carefully-dried samples. Distinct water and strongly hydrogen-bonded proton species have been detected. The latter are particularly noteworthy and they are present in kanemite, octosilicate, magadiite and kenyaite, but not in makatite or layered silicic acids. Interactions between the resolved proton species have been investigated with a series of 1- and 2-dimensional experiments resulting in the detection of mixing, via spin-diffusion or chemical exchange. Sodium-23 NMR studies were complicated by second-order effects from strong quadrupolar interactions and the presence of a significant signal from a sodium chloride contamination in many samples. The latter had fooled previous authors. Acidification products of kanemite, octosilicate and magadiite were characterised by (^29)Si CP NMR, thermogravimetric analysis, 1H MAS NMR and powder X-ray diffraction. A single H-kanemite sample proved to be H(_2)Si(_2)O(_5), but two types of H-octosilicate and H-magadiite sample were prepared. These differed in the presence of interlayer water. Several CP experiments were used to investigate the relationship between (^29)Si and (^23)Na nuclei and protons in the silicates. Cross-polarisation mechanisms tended to involve magnetisation transfer from the H-bonded protons only. Their determination was possible with a consideration of the extent of spin-diffusion or chemical exchange over the time-scale of the relevant experiments. Finally, new model structures for kanemite and the interlayer space in kanemite, octosilicate, magadiite and kenyaite have been suggested, while previously- proposed silicate layers have been reconsidered.

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8

Keevil, Stephen Frederick. "Experimental techniques to characterise localisation in nuclear magnetic resonance spectroscopy." Thesis, King's College London (University of London), 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268303.

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9

Friedrich, J. O. "Frequency and spatial selectivity in nuclear magnetic resonance spectroscopy." Thesis, University of Oxford, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234964.

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10

Champion, de Crespigny Alexander James Stephen. "Spatial localisation in nuclear magnetic resonance imaging and spectroscopy." Thesis, University of Cambridge, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386006.

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11

Woodruff, Nicholas D. "Investigation of protein structure and folding by NMR spectroscopy." Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302124.

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12

Lucena, Alcalde Guillermo. "New developments in chromatographic NMR." Thesis, University of Sussex, 2018. http://sro.sussex.ac.uk/id/eprint/76636/.

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Analysis in chemistry has always been hindered by the presence of impurities in samples or mixtures that are difficult to separate. Nuclear magnetic resonance has proven to be one of the most powerful analysis techniques to enable the study of mixtures by pseudoseparation using molecular parameters such as the diffusion coefficient through the application of the DOSY technique. In order to extend the application of this technique, an improvement has been proposed know as matrix-assisted DOSY (MAD-DOSY) or chromatographic NMR. This technique is based on the addition of a sample modifier that will interact differently with the molecules, varying and separating their diffusion coefficients, or even changing slightly the chemical shifts. To extend the application of chromatographic NMR, size exclusion stationary phases have been combined with DOSY experiments. These studies have been applied to analyze mixtures modifying the diffusion coefficient in terms of size exclusion behavior and to increase the understanding of the interactions between the analytes and the stationary phase. These studies have been published in Magnetic Resonance in Chemistry. One of the main issues when using DOSY is spectral overlapping, which is the main cause of poor resolution. In addition to this problem, a consequence of using stationary phases is the appearance of increased broadening of the signals due to differences in magnetic susceptibility. Thus, to achieve the aim, the study of diffusion properties have been performed under HR-MAS conditions which can help to remove susceptibility effect, but has complicating effects on the DOSY experiment. A method to obtain reliable diffusion measurements under HR-MAS have been developed using a D2O sample. Different conditions have been investigated including different pulse sequences, variation of parameters of the pulse sequence (diffusion delay or gradient strength), spinning rate and synchronization of the pulse sequence with the sample spinning. Also improvements in sample preparation as the addition of spacers in different locations of the sample rotor, to both reduce radial field variations and the sample volume, in order to obtain the most accurate diffusion values. This method have been published in Magnetic Resonance in Chemistry. The method have been applied to a wide range of molecules to extend the understanding of diffusion under HR-MAS conditions. In order to extend the range of application of NMR chromatography, a complementary study of the analysis of a mixture of different enantiomers including ethylenediamine cobalt complexes, aminoacids and some other organic small molecules adding to the sample a chiral stationary phase as a sample modifier is included in the final chapter of this thesis.

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13

Eyles, Stephen J. "Studies of protein folding by NMR spectroscopy." Thesis, University of Oxford, 1995. http://ora.ox.ac.uk/objects/uuid:06b8fb16-790c-4b72-80d0-8317920655fe.

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This thesis describes an investigation of the folding and stability of a series of derivatives of the proteins lysozyme and α-lactalbumin which lack one or more of their four native disulphide bridges. Removal of the disulphide bridge which links the N- and C-termini from hen lysozyme results in a three-disulphide derivative (CM^6,127-lysozyme). This has a profound effect on its stability against thermal denaturation, the T_m for unfolding being reduced by 25°C at pH 3.8. Calorimetric measurements performed on this three-disulphide derivative indicate that this reduction in stability may be attributed entirely to an increase in the entropy difference between the native and denatured states. Kinetic refolding studies of CM^6,127-lysozyme using stopped flow optical methods and hydrogen exchange pulse labelling in conjunction with NMR and electrospray ionisation mass spectrometry (ESI-MS) suggest that this reduced stability manifests itself primarily in the α-domain of the protein. A transient intermediate populated during refolding of the unmodified protein can no longer be detected during folding of the derivative resulting in highly cooperative folding under the conditions investigated. The structure and stability of a three- and two-disulphide derivative of the homologous protein, α-lactalbumin have been investigated by NMR spectroscopy. The three-disulphide species, like its lysozyme counterpart, can adopt native structure but this is much more unstable than the intact protein. Removal of a second disulphide bridge, however, destabilises α-lactalbumin to the extent that the native state is no longer formed. Instead, in the presence of Ca²⁺ and high concentrations of salt, a partially structured state is induced which has some elements of tertiary structure present. Novel techniques of ESI-MS have been developed to study protein folding and stability using hydrogen exchange techniques. Applications to the investigation of cooperativity in protein folding, stability in native, partially folded and unfolded states, and the interactions of a partially folded protein with the chaperone GroEL are described.

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14

Yang, Yinhua. "Application of biomolecular NMR spectroscopy for protein structure determination." Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B42182013.

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15

Chiu, Pui-wai, and 趙沛慧. "¹H and ³¹P brain magnetic resonance spectroscopy in aging." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B47170505.

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Magnetic Resonance Spectroscopy (MRS) was used to study the relationship between brain regional concentrations of metabolites and normal aging in Chinese. Our goal in this study is to create a database of normal aging and hence enhance further understanding on the degenerative process leading to dementia and related neurodegenerative diseases. Thirty cognitively normal healthy volunteers of age 22-82 years were recruited and the bias on gender effect in data sampling was minimized by recruiting 15 females and 15 males. In the first part of the study, 1H MRS was obtained using single-voxel-spectroscopy (SVS). Offline software java-based version of Magnetic Resonance User Interface (jMRUI) was employed for data analysis. Cerebrospinal fluid was normalized using software voxel based morphormetry (VBM). Brain morphometry data was also analyzed. Brain metabolites choline (Cho), creatine (Cr) and N-acetyl aspartate (NAA) were quantified using internal water as reference. It was found that brain metabolite concentrations of Cr, Cho and NAA increase significantly with age. Gender effect on metabolite concentrations were also discovered, being higher in the female group. For brain morphometry, white matter and grey matter volumes and fractions all reveal a siginificant negative correlation with age, whereas CSF volume and fraction show a significant positive correlation with age. Gender effect was found on grey matter, white matter and intracranial volume, being higher in the male group. In the second part of the study, 31P SVS MRS was performed on the same population of volunteers. jMRUI was also employed for data analysis. Metabolic ratios were obtained. Similar to the 1H MRS study, apart from creating a database in studying normal aging, an additional aim of this 31P MRS study is to correlate with 1H MRS and assist in interpreting the corresponding metabolic activity. Brain metabolite concentrations were found to increase significantly with age. The increase of PCr (phosphocreatine)/Ptot (total phosphorus content) in posterior cingulate suggests lower metabolic activity throughout the course of aging. The strong evidence of PDE (phosphodiester) increase with age in left hippocampus proposes the fact that phospholipid membrane breakdown will be enhanced by aging. In conclusion, MRS can act as a non-invasive tool to study aging at molecular level. Metabolite levels are significant means to investigate the metabolic change in the human brain during the process of aging as the variations in metabolite levels are believed to be footprints of biochemical changes.
published_or_final_version
Diagnostic Radiology
Master
Master of Philosophy

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16

Krishnan, Mangala Sunder. "Applications of irreducible spherical tensor operators to NMR and NQR spectroscopy." Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=75771.

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The thesis extends the concept of Irreducible Spherical Tensor Operators to spin dynamics problems in Nuclear Magnetic and Quadrupole Resonance Spectroscopy. NQR and solid state NMR deal with spin systems which behave as effective single spins in many, pulsed experiments, or as multispin systems when the dipolar interactions among spins cannot be neglected. The thesis considers problems in both areas. New analytic results are derived in the thesis for pure NQR spectroscopy and for the effect of radiofrequency fields in the presence of electric quadrupolar interaction. Three-pulse experiments are proposed for a spin-5/2 system and quantitative calculations are done for the indirect detection of new observables. Attention is focussed on the usefulness of the full-spin density matrix in all these calculations. In addition the concept of multispin tensors is applied to a system of spin-1/2 nuclei with strong dipolar interactions. This leads to coupled differential equations for correlations among spins for which an iterative solution can be obtained. The solutions are discussed in relation to Free Induction Decay experiments available for $ sp{19}$F nuclei in CaF$ sb2$ crystal.

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17

Guitard, Pierre-André. "Local Nuclear Magnetic Resonance Spectroscopy with Giant Magnetoresistive Sensors." Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLS175/document.

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La Spectroscopie par Résonance Magnétique Nucléaire (NMRS) est une technique largement connue pour l'analyse de molécules chimique et biologiques. Cependant, en raison de la faible intensité des signaux de RMN, il est très difficile de travailler sur des volumes inférieurs à un mm³. Cette limitation a conduit à la mise au point de capteurs miniaturisés tels que les microbobines, les centres NV et des magnétomètres atomiques. Au cours de cette thèse nous avons développé une approche basée sur l'utilisation de capteurs à MagnétoRésistance Géante (GMR), capteurs magnétiques à large de la bande, capable de détecter localement le signal RMN. Les capteurs GMR, sur différents substrats tels que le silicium, le verre et l’alumine, ainsi que la configuration du montage RMN ont été spécifiquement conçus pour avoir une détectivité dans la gamme de 20pt/sqrt(Hz) et capable de travailler avec un champ magnétique externe jusqu'à 1 Tesla. Nous allons d’abord présenter les résultats obtenus à 0.3T sur de l’eau, dans la configuration où la RMN locale est effectuée dans un grand volume, mettant en évidence le caractère fonctionnel du montage. Puis les résultats obtenus, également à 0.3T, de la spectroscopie RMN de liquides modèle comme l'éthanol où le volume sondé estimé est de l’ordre de 20x20x20μm³. Finalement un résultat à un champ magnétique plus élevé, 0.6T, a également été montré sur de l’eau
Nuclear Magnetic Resonance Spectroscopy (NMRS) is a widely known technique for chemical and biological molecule analysis. However due to the weakness of the NMR signals, it is very difficult to work on volumes lower than a mm³. That limitation has led to the development of miniaturized sensors such as microcoils, NV centers and atomic magnetometers. We will present our approach based on the use of Giant Magnetoresistive sensors (GMR) as wide band magnetic sensors to detect locally the NMR signal. GMR sensors and NMR set up have been specifically designed to have a detectivity in the range of 20pt/sqrt(Hz) and able to work with external magnetic field up to 1T. We will first present the results obtained at 0.3T on water, in the configuration where the local NMR is done on a high volume, highlighting the functionality of the set-up. Then we will show the results obtained also at 0.3T, of NMR spectroscopy of model liquids like Ethanol on a volume of the order of 20x20x20μm³. Finally, a result at a higher magnetic field, 0.6T, has also been obtained on water

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18

Cousin, Samuel. "Two-field nuclear magnetic resonance : spectroscopy and relaxation." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066354/document.

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Cette thèse traite de la RMN en phase liquide à champs multiples, pour la détermination de la structure et de la dynamique de petites molécules et de protéines. La dynamique ps-ns des chaînes latérales de la protéine ubiquitine a été étudiée par la relaxation du 13C des groupes méthyles δ1 des isoleucines, marqués sélectivement. Les vitesses de relaxation mesurées à plusieurs hauts champs magnétiques et les vitesses de relaxation longitudinale de 0.29 T à 9 T obtenues par relaxométrie haute résolution ont été analysées à l'aide du programme ICARUS, adapté à l’occasion pour les groupes méthyle. La matrice de relaxation a été calculée par un programme inédit, nommé RedKite. Un modèle de fonction de densité spectrale a été proposé pour prendre en compte les mouvements complexes des groupes méthyles. Nous avons ainsi pu accéder à une description de la dynamique des groupes méthyle sur trois ordres de grandeur d’échelles de temps. La spectroscopie RMN à deux champs magnétiques a été développée en collaboration avec Bruker. Le spectromètre à deux champs permet le contrôle des spins dans deux centres magnétiques avec une homogénéité suffisante et le transfert rapide de l’échantillon entre ces deux centres. Grâce à l'utilisation de cohérences à zéro-quantum, nous avons mesuré des spectres de corrélation homo- et hétéronucléaires à haute résolution dans lesquels les deux dimensions sont obtenues à deux champs très différents. Cette approche a été utilisée pour réduire considérablement la contribution de l’échange chimique à la relaxation transverse, permettant l’observation des signaux de noyaux en échange chimique invisibles à haut champ
We present the development of multiple-field liquid-state NMR spectroscopy for the determination of the structure and dynamics of small molecules and proteins. Dynamics of proteins side-chains in the pico- to nanosecond range have been studied in the protein ubiquitin, by measuring the relaxation of carbon-13 nuclei in isoleucine-δ1 methyl groups, with site-specific isotope labelling. High-field relaxation rates and longitudinal relaxation rates obtained using high-resolution relaxometry have been analysed using a new version of the program ICARUS, adapted for methyl groups. The relaxation matrix has been calculated with a homemade program called RedKite. Models of spectral density function have been proposed to account for all motions of methyl groups. This unprecedented dataset allows for the description of motions in methyl groups over 3 orders of magnitudes of correlation times. Two-field NMR has been developed in collaboration with Bruker. The two-field NMR spectrometer allows for the control of nuclear spins in two magnetic centres with vastly different magnetic fields, coupled with a sample shuttle. Using zero-quantum coherences, homo and heteronuclear two-field high-resolution spectra have been obtained, where the two dimensions are acquired at very different magnetic fields. Such pulse sequences have been used to reduce the contribution of chemical exchange to transverse relaxation, even when this exchange makes signals invisible at high field. The reduced bandwidth of signals at low field has also been used to perform efficient isotropic mixing in a two-field TOCSY experiment. Correlations have been observed for carbon-13 signals separated by more than 150 ppm

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19

Jones, Jonathan A. "Nuclear magnetic resonance data processing methods." Thesis, University of Oxford, 1992. http://ora.ox.ac.uk/objects/uuid:7df97c9a-4e65-4c10-83eb-dfaccfdccefe.

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This thesis describes the application of a wide variety of data processing methods, in particular the Maximum Entropy Method (MEM), to data from Nuclear Magnetic Resonance (NMR) experiments. Chapter 1 provides a brief introduction to NMR and to data processing, which is developed in chapter 2. NMR is described in terms of the classical model due to Bloch, and the principles of conventional (Fourier transform) data processing developed. This is followed by a description of less conventional techniques. The MEM is derived on several grounds, and related to both Bayesian reasoning and Shannon information theory. Chapter 3 describes several methods of evaluating the quality of NMR spectra obtained by a variety of data processing techniques; the simple criterion of spectral appearance is shown to be completely unsatisfactory. A Monte Carlo method is described which allows several different techniques to be compared, and the relative advantages of Fourier transformation and the MEM are assessed. Chapter 4 describes in vivo NMR, particularly the application of the MEM to data from Phase Modulated Rotating Frame Imaging (PMRFI) experiments. In this case the conventional data processing is highly unsatisfactory, and MEM processing results in much clearer spectra. Chapter 5 describes the application of a range of techniques to the estimation and removal of splittings from NMR spectra. The various techniques are discussed using simple examples, and then applied to data from the amino acid iso-leucine. The thesis ends with five appendices which contain historical and philosophical notes, detailed calculations pertaining to PMRFI spectra, and a listing of the MEM computer program.

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20

Bilinovich, Stephanie M. "Nuclear Magnetic Resonance Spectroscopy in the Study of Protein Complexes." University of Akron / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=akron1396871078.

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21

Marsih, I. Nyoman. "A mechanistic study of the Fischer-Tropsch reaction by '1'3C NMR spectroscopy." Thesis, University of Sheffield, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370074.

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22

Yang, Yinhua, and 楊銀花. "Application of biomolecular NMR spectroscopy for protein structure determination." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B42182013.

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23

Gong, Qingguo. "NMR analysis of bovine tRNA Trp /." View Abstract or Full-Text, 2002. http://library.ust.hk/cgi/db/thesis.pl?BICH%202002%20GONG.

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Thesis (Ph. D.)--Hong Kong University of Science and Technology, 2002.
Includes bibliographical references (leaves 105-123). Also available in electronic version. Access restricted to campus users.

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24

Smith, K. I. "The two-dimensional nuclear magnetic resonance spectroscopy analysis of peptides in solution." Thesis, University of Manchester, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377720.

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25

Brereton, Ian Malcolm. "A multinuclear NMR study of inclusion processes /." Title page, contents and introduction only, 1985. http://web4.library.adelaide.edu.au/theses/09PH/09phb841.pdf.

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26

Nagapudi, Karthik. "Solid-state NMR investigation of structure and dynamics of polyrotaxanes." Thesis, Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/8638.

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27

Kurniawan, Nyoman Dana. "Dissection of the human low-density lipoprotein receptor structure using NMR spectroscopy /." [St. Luica, Qld.], 2002. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16824.pdf.

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28

Kontos, Athanasios G. "An '8'9Y and '6'3Cu NMR study of some high-Tâ†c superconductors." Thesis, University of Warwick, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282434.

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29

Nayler, Graham L. "Applications of composite pulse techniques to the determination of multiplicity in carbon-13 NMR spectroscopy." Thesis, University of Manchester, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277349.

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30

Liu, Zhihong. "Structural analysis of amylin and its analogs by NMR spectroscopy /." Thesis, Connect to this title online; UW restricted, 1999. http://hdl.handle.net/1773/8657.

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31

Olsen, Katherine Anna. "NMR studies reveal the kinetics and thermodynamics of hairpin formation /." Thesis, Connect to this title online; UW restricted, 2006. http://hdl.handle.net/1773/8611.

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32

Mingione, Velia. "Characterization of carotenoid pigments in Atlantic salmon using Nuclear Magnetic Resonance spectroscopy." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.

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La Norvegia è il leader mondiale per la produzione di salmone dell’Atlantico (Salmo salar). Il salmone norvegese è la specie più commercializzata in Europa e la terza specie ittica più consumata nel mondo (EUMOFA, 2016). La qualità del pesce è un concetto complesso che coinvolge diversi fattori come sicurezza, qualità nutrizionale, disponibilità, convenienza e altri attributi come colore e freschezza (Botta, 1995; Cardello, 1995). La pigmentazione muscolare nei salmonidi d'allevamento è considerata il parametro di qualità più importante dopo la freschezza (García-Chavarría et al., 2013). Studi sul comportamento del consumatore hanno dimostrato che la colorazione di questo prodotto viene inconsciamente relazionata con valore nutritivo, salubrità, freschezza e gusto. Difatti, al momento dell’acquisto, i consumatori hanno affermato che il colore è un parametro molto influente e sono disposti a pagare di più per un salmone più “rosso” (Anderson, 2000; García-Chavarría et al., 2013). La tipica colorazione rosata che caratterizza i salmonidi è dovuta ai carotenoidi (Shahidi et al., 1998). L’alimentazione con questi pigmenti è considerata la pratica di allevamento più importante per il salmone (Moe, 1990). Per questo motivo, ci sono diversi studi al riguardo. Lo scopo di questa tesi è sviluppare una metodologia per estrarre ed analizzare i principali carotenoidi presenti nel tessuto muscolare e negli organi dei salmonidi, tramite l’utilizzo della Risonanza Magnetica Nucleare ad alta risoluzione (HR 1H-NMR).

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33

Zagdoun, Alexandre. "Dynamic Nuclear Polarisation Surface Enhanced NMR Spectroscopy." Phd thesis, Ecole normale supérieure de lyon - ENS LYON, 2014. http://tel.archives-ouvertes.fr/tel-01065554.

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Since its discovery in the 1950's, DNP has been a topic of significant interest in magnetic resonance. DNP is the transfer of polarization between single electrons and nuclei, driven by micro-wave irradiation. Since its renaissance at high field in the 90's, due to the introduction of gyrotrons as high-power, high-frequency microwave sources most application of this technique have been samples of biological interest in frozen solution. The long standing interest of our group in the characterization of surface species such as supported catalysts on silica lead us to apply this technique to the study of surfaces. The goal of this thesis is the development of this method, dubbed DNP Surface Enhanced NMR Spectroscopy. To that end, we first introduce new polarizing agents, soluble in organic solvents. The influence of the electron relaxation times on the DNP enhancements is demonstrated and efficient tailored polarizing agents are introduced. The optimization of the sample preparation to obtain optimal sensitivity is also discussed, as well as the interaction between the radical and the surface. These developments made it possible to apply the technique to many functionalized materials, with some examples developed in this manuscript. Finally, the issue of DNP on polarization conductors is discussed, and we show how microcrystals can be efficiently polarized using DNP.

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Groves, Ronald William. "O17 spin-lattice relaxation solid state NMR studies of pure and doped ices." Columbus, Ohio : Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1021903674.

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Thesis (Ph. D.)--Ohio State University, 2002.
Title from first page of PDF file. Document formatted into pages; contains xx, 128 p.; also contains graphics. Includes abstract and vita. Co-advisors: Charles H. Pennington and James V. Coe, Dept. of Chemistry. Includes bibliographical references (p. 124-128).

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Guan, Xiao. "NMR approaches to protein conformation and backbone dynamics studies on hyperthermophilic acylphosphatase and neuropeptide secretoneurin /." Click to view the E-thesis via HKUTO, 2010. http://sunzi.lib.hku.hk/hkuto/record/B44079230.

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36

Wade, Bruce Edward. "High temperature, high resolution nuclear magnetic resonance of Poly (p-phenylene sulfide)." Thesis, Georgia Institute of Technology, 1989. http://hdl.handle.net/1853/10034.

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Li, Xiaohua. "NMR of group 2 element quadrupolar nuclei and some applications in materials science and biology." Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/30998.

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38

Campbell, Susan Christina. "Pharmaceutical polymorphism : an investigation using solid-state nuclear magnetic resonance spectroscopy." Thesis, Durham University, 1998. http://etheses.dur.ac.uk/5021/.

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The study of two pharmaceutically active systems that each display polymorphism has provided a platform upon which to develop and apply solid-state NMR techniques in order to increase the understanding of the solid-state structure of small organic molecules. The multidisciplinary approach adopted has highlighted the advantages of solid-state NMR as a non-invasive probe of molecular conformation and crystallographic packing.Carbon-13 CP/MAS spectra of the two polymorphs of BRL55834 - a fluorinated benzopyran derivative - immediately suggest the presence of one and three molecules in the asymmetric unit. A lack of crystals suitable for single-crystal XRD has catalysed the application of high-power powder X-ray diffraction studies. Subsequent attempts at structure solution using Genetic Algorithm techniques are showing preliminary results that reinforce predictions made from solid-state NMR. Novel triple-channel techniques have aided assignment and resolution of die complex (^13)C CP/MAS spectra. Enrichment of the (^15)N site appears to have resulted in the formation of a new polymorph. Techniques for the analysis of detection Units have been developed using solid-state Raman spectroscopy and chemometric analysis. The aminoxanthine derivative, BRL61063, provides interesting inter-form variations in molecular disorder, solid-state packing, and hydrogen bonding. A previously basic understanding of the single-crystal XRD data has been further evaluated through the course of this Ph.D. and solid-state NMR spectral editing techniques have been developed and applied to identify these phenomena. Recrystallisation studies have produced two samples that appear to exist in an intermediate state between the rigid and mobile structural limits. Temperature variation causes interesting changes in the relaxation characteristics and natural abundance (^15)N and (^13)C CP/MAS spectra. Residual dipolar coupling effects vary in their manifestation within the (^13)C CP/MAS spectra of the polymorphic systems studied and comparison with the literature yields important information regarding molecular conformation. Nitrogen-15 enrichment and operation at higher magnetic field have been applied to reduce these second order effects. Finally, some distance has been travelled along the path towards decoupling (^14)N. Future development of this technique holds potential for resolution enhancement in the solid state spectra of most naturally occurring, nitrogen-containing molecules.

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39

Gale, Paul. "Bacteriorhodopsin/phospholipid interactions : a study by ³¹P- and ²H-NMR." Thesis, University of Oxford, 1988. http://ora.ox.ac.uk/objects/uuid:e5f11388-8613-442d-9a13-d20eea92bc84.

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Two methods were used to produce exogenous lipid/bR complexes. A detergent method (Huang et al., 1980) reconstituted bR into DMPC or DMPG bilayers, free of all endogenous purple membrane lipids as shown by high resolution ³¹ P-NMR. A novel biological detergent-free method employed bovine liver non-specific lipid transfer protein (nsTP) to mediate addition of DMPC to purple membrane, while retaining 76 - 86% of the endogenous purple membrane phospholipids. The variations with temperature of 2H-NMR quadrupole splittings for the DMPC choline α- and β-methylene CD2 segments were similar to those for protein-free lipid (Gaily et al., 1975) implying that temperature dependent changes in segmental amplitudes of motion within the choline group are preserved in the presence of bR. Incorporation of small quantities of bR increased the amplitudes of segmental motion within the choline headgroup relative to that of pure lipid, but increasing the bR content induced an ordering effect. The choline α- and β-methylene segment quadrupole splittings showed a linear variation with protein content at constant temperature. This is consistent with freeze fracture electron microscopy data, which shows the bR particles to be dispersed at all lipid/protein ratios, when quenched from temperatures above the phase transition. Applying a fast two site exchange model to the ²H-NMR data, values between 12 and 15 were calculated for the number of boundary lipids for bR (26,000 M_r) in DMPC bilayers free of purple membrane lipids. From ESR data, for delipidated bR in DMPC and DMPG bilayers at temperatures above the phase transition, the number of boundary lipids calculated were 18 - 21, which is consistent with the bR being monomeric, as also observed in DMPC bilayers with all the purple membrane lipids retained (Cherry et al., 1978). The purple membrane lipids thus appear to mediate crystallization of the bR particles into a hexagonal lattice at temperatures slightly below the exogenous lipid phase transition.

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40

Zhao, Tiejun. "NMR pulse sequence development and studies of threaded macromolecules." Diss., Available online, Georgia Institute of Technology, 2004:, 2004. http://etd.gatech.edu/theses/available/etd-06072004-131430/unrestricted/zhao%5Ftiejun%5F200405%5Fphd.pdf.

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Kesling, Brian D. "Synthesis and characterization of molecularly doped tri-p-tolylamine/polycarbonate blends using solid-state NMR." Morgantown, W. Va. : [West Virginia University Libraries], 2004. https://etd.wvu.edu/etd/controller.jsp?moduleName=documentdata&jsp%5FetdId=3597.

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Thesis (Ph. D.)--West Virginia University, 2004.
Title from document title page. Document formatted into pages; contains v, 68 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 68).

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42

郭伯章 and Bozhang Guo. "NMR spectroscopic and kinetic studies on acyclic and homocyclic enols." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1988. http://hub.hku.hk/bib/B31231135.

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Guo, Bozhang. "NMR spectroscopic and kinetic studies on acyclic and homocyclic enols /." [Hong Kong : University of Hong Kong], 1988. http://sunzi.lib.hku.hk/hkuto/record.jsp?B12352366.

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44

Lechtenberg, Bernhard Clemens. "Thrombin allostery and interactions probed by NMR spectroscopy and crystallography." Thesis, University of Cambridge, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.610702.

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45

Guan, Xiao, and 关晓. "NMR approaches to protein conformation and backbone dynamics: studies on hyperthermophilicacylphosphatase and neuropeptide secretoneurin." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B44079230.

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46

Richardson, Julia Margaret. "The measurement of coupling constants and the use of heteronuclear cross-polarisation in NMR experiments for the study of proteins." Thesis, University of Cambridge, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.281970.

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47

Pooransingh-Margolis, Neela. "Vanadium-51 solid-state magic angle spinning NMR spectroscopy of vanadium haloperixodases and oxovanadium (V) haloperoxidase mimics." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 2.19 Mb., 157 p, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:3200531.

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48

Sannigrahi, Poulomi. "Composition and cycling of natural organic matter: Insights from NMR spectroscopy." Diss., Available online, Georgia Institute of Technology, 2005, 2005. http://etd.gatech.edu/theses/available/etd-11272005-094111/.

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Thesis (Ph. D.)--Earth and Atmospheric Sciences, Georgia Institute of Technology, 2006.
Taillefert, Martial, Committee Member ; Weber, Rodney, Committee Member ; Stack, Andrew, Committee Member ; Benner, Ronald, Committee Member ; Ingall, Ellery, Committee Chair. Includes bibliographical references.

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49

Morris, Daniel L. "NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY IN THE STUDY OF PROTEIN-LIGAND INTERACTIONS." University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron1524681449524557.

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50

Gao, Lei. "Determination of quantitative nutritional labeling compositional data of lipids by Nuclear Magnetic Resonance (NMR) spectroscopy." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=111577.

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The application of Nuclear Magnetic Resonance (NMR) spectroscopy in the determination of nutrition labeling component data (NLCD) was investigated, with the intent of using this methodology as a primary method to calibrate FTIR instrumentation for NLCD confirmation or screening on a routine basis. Unlike previous NMR studies, this work used three strategies to attain accuracy and reproducibility of NLCD through: (i) appropriate setting of operational parameters for spectral acquisition; (ii) resonance selection by optimizing the signal in proportion to the nuclei population and (iii) integration of resonances by pre-defined fixed chemical shift ranges. Both of 13C NMR spectra and 1H NMR spectra were shown to provide robust and acceptable results on the condition of appropriate acquisition of spectra for quantization purposes and the adoption of standard procedures for spectral processing, integration and calculation purposes. A quantitative approach of NLCD including trans content was determined by the interpretation resonance signals of 13C's and 1H's from methylene groups presented in triglyceride complex of fats and oils. An alternative method based on partial-least-squares (PLS) calibrations was provided as well, the latter proved to be especially useful in dealing with overlapping bands frequently found in 1H spectra. With the diagnostic provided by PLS, the trans and cis signals were shown to be separated in 1H spectra. It is the premise for the trans fat determination based on 1H spectra. Unit conversion from mole to weight % was addressed and a solution was developed based on NMR data per se, without significant assumptions. Validation involving the analysis of three different lipid types (model triacylglycerols, refined and hydrogenated oils) demonstrated that NMR predictions of NLCD were in good agreement with those results either from samples' actual values as well as those obtained using GC and FTIR predictions. Thus with appropriate integration of instrumentation, software and spectral processing accessories, both 13C and 1H NMR can determine NLCD, but with the capability to determine trans, 1H NMR is more practical than 13C NMR due to its much shorter spectral acquisition time. Thus NMR can serve as a primary method for the calibration of FTIR instrumentation, a practical instrumental method for routine NLCD determination and screening.

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