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1

Zhou, Xiangzhi. "An Analysis of NMRD profiles and ESR lineshapes of MRI Contrast Agents." Doctoral thesis, Umeå : Univ, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-361.

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2

Huang, Yang. "Analysis of NMR Spin-lattice Relaxation Dispersion on Complex Systems." Doctoral thesis, Umeå universitet, Kemiska institutionen, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-110721.

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This thesis focus on the analysis of spin-lattice NMRD relaxation profilesmeasured in various complex systems such as proteins, zeolites and ionicliquids. Proton, deuterium and fluoride T1-NMRD relaxation profiles wereobtained from a fast-field cycling (FFC) instrument. It is found that alsopossible to obtain NMRD profiles from the molecular dynamics (MD)simulation trajectories. NMRD Profiles were analyzed by using differentrelaxation models, such as the Solomon-Bloembergen-Morgan (SBM) theoryand the Stochastic Liouville (SL) theory. Paper I described the hydration of protein PrxV obtained from a MDsimulation, and compared with the picture emerges from an analysis byusing a generally accepted relaxation model [appendix C]. The result showsthat the information from NMRD analysis is an averaged picture of watermolecules with similar relaxation times; and the MD simulations containsinformation of all types of interested water molecules with differentresidence times. In paper II NMRD profiles have been used to characterize the hydration ofthe oxygen-evolving complex in state S1 of photosystem II. NMRDexperiments were performed on both intact protein samples and Mndepletedsamples, and characteristic dispersion difference were foundbetween 0.03 MHz to 1 MHz; approximately. Both the SBM theory and theSL theory have been used to explain this dispersion difference, and it isfound that this is due to a paramagnetic enhancement of 1-2 water moleculesnearby ~10 Å from the spin center of the Mn4CaO5 cluster. The result showsthe reorientation of the molecular cluster is in μs time interval. Whencompare these two theories, the SL theory presented a better interpretationbecause parameters obtained from the SBM theory shows they didn’t fulfilthe presupposed perturbation criterion (the Kubo term). Paper III deals with the water dynamics in the restricted/confined spaces inthe zeolite samples (H-ZSM-5 and NH4-ZSM-5) and obtained by proton anddeuterium spin-lattice NMRD profiles. The results show that the spin-latticeNMRD can be used to characterize various zeolites. The temperature has aweak effect on the relaxation rate R1, but the change of different counter ionsmay change the hydration and the translational diffusion pores and givedifferent R1. Proton and fluoride NMRD profiles and MD simulations were both used tostudy the dynamics of BMIM[PF6] in paper IV. Results indicate the reorientation of the molecules are in the ns time regime, and the effectivecorrelation time obtained from 1H and 19F are the same. From the MDsimulation it is found the reorientation of [PF6]- ions is much faster (in ps)compare with BMIM+ ion which moves in the ns time range. With previous results, the FFC NMRD profiles are indeed very informativetools to study the molecular dynamics of complex systems. The MDsimulation can be used as a complementary method to obtain detailedinformation. By combine these two methods, it provide a more colorfulpicture in the study of protein hydration and liquid molecular dynamics.
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3

Pedacchia, Marta. "Rilassometria NMR per lo studio degli ioni cobalto nel cobaltismo da artroprotesi." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/8330/.

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Il rilascio di detriti d’usura metallici è una grave problematicità connessa ai sistemi protesici, e principalmente riguarda le protesi d’anca ad accoppiamento metallo su metallo in lega CoCr. La presenza di un livello di ioni Co nel siero che supera la soglia di tossicità è correlata a metallosi periprotesica eal fallimento del l’impianto. Recentemente è emersa un’altra casistica, presumibilmente connessa alla distribuzione e accumulo di questi ioni in tessuti di organi anche lontani dall’impianto, che si manifesta con una sintomatologia sistemica analoga a casi noti di avvelenamento da Cobalto. Nel contesto di questa nuova patologia sarebbe di grande interesse la possibilità di monitorare in-vivo la distribuzione del Cobalto rilasciato da protesi articolari, in organi o tessuti di pazienti che manifestano alti ivelli ionici di Co nel siero utilizzando metodiche non invasive come l’NMR. L’ipotesi sperimentale di applicabilità prende spunto dalle proprietà magnetiche che alcuni composti del Cobalto possono presentare nell’organismo. In questo lavoro sperimentale, nato dalla collaborazione tra il laboratorio NMR del DIFA dell’Università di Bologna e l’Istituto Ortopedico Rizzoli (IOR) di Bolgna, si presentano i risultati relativi allo studio di fattibilità condotto con diverse metodiche di rilassometria NMR su campioni biologici in presenza di Co. L’obiettivo riguarda la caratterizzazione delle proprietà di rilassamento con elettromagnete a temperatura ambiente e fisiologica, e la valutazione delle dinamiche molecolari dai profili NMRD ottenuti alle basse frequenze con metodica Fast Field Cycling, dei nuclei 1H di tali sistemi in presenza di Co.
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4

Hoffmann, Dirk. "NMR-Untersuchungen an Nanokapsel-Dispersionen - NMR investigations on nanocapsule dispersions." Gerhard-Mercator-Universitaet Duisburg, 2001. http://www.ub.uni-duisburg.de/ETD-db/theses/available/duett-05302001-102514/.

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Nanocapsules are generally considered as spherical, hollow structures. Important potential applications are pharmaceutically related such as drug targeting and controlled release. Typically, the capsules consist of a polymeric wall, filled with an oil which can dissolve lipophilic agents. To enable a stable aqueous dispersion, the capsule surface is covered by an amphiphilic surfactant. Nanocapsule-dispersions were investigated by means of solid-state nmr. Cross polarization experiments revealed the morphology of the polymeric wall. Further, the spin-lattice relaxation times for the proton magnetization in the rotating frame were studied under direct excitation as well as under cross polarization conditions. Based on the results, a special mechanism of cross polarization is proposed, initiated by a temporary adsorption of mobile oil- and surfactant-molecules to the more rigid capsule surface. - Nanokapseln sind sphärische, hohle Objekte, die in der Medizin als gewebespzifische Wirkstoff-Träger-Systeme eingesetzt werden sollen. Vereinfacht bestehen die Kapseln aus einem Öltropfen, der von einem Polymergerüst umgeben ist. In die innere Ölphase können lipophile Wirkstoffe eingeschlossen werden. Die Nanokapselwand ist mit einer Tensidschicht umgeben, die stabilisierend wirkt und ermöglicht, dass die Kapseln in einer wässerigen Phase dispergiert werden können. Als analytische Methode wurde die Festkörper-NMR-Spektroskopie gewählt. Die Morphologie der Polymerwand wurde mit Kreuzpolarisationsexperimenten aufgeklärt. Zusätzlich wurden die Relaxationszeiten im rotierenden Koordinatensystem der Protonen unter Direktanregungs- und Kreuzpolarisationsbedingungen untersucht. Die Ergebnisse dieser Untersuchungen konnten mit einer temporären Adsorption der Öl- und Tensidmoleküle an der Nanokapseloberfläche interpretiert werden.
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5

Lenz, Eva-Maria. "Multinuclear NMR and HPLC-NMR spectroscopic studies on xenobiotic metabolism." Thesis, Birkbeck (University of London), 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267785.

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6

Lee, Jaehyuk. "A portable NMR." Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609637.

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7

Karvonen, V. (Ville). "NMR-spektroskopia lääkeaineanalytiikassa." Bachelor's thesis, University of Oulu, 2017. http://urn.fi/URN:NBN:fi:oulu-201705232041.

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NMR-spektroskopia perustuu ytimien ydinmagnettisen resonanssin mittaamiseen. Menetelmä on kasvattanut suosiotaan lääkeaineanalytiikassa aina ilmiön löytämisestä lähtien. Tässä tutkielmassa perehdytään NMR-spektroskopian teoriaan ja sen käyttöön lääkeaineanalytiikassa, jossa NMR-menetelmä tulee päivä päivältä tärkeämmäksi ja yleisemmäksi. NMR-spektroskopia on nopea, informatiivinen, eikä kalliiden tai monimutkaisten standardien käyttö ole menetelmässä tarpeellista. Menetelmää voidaan periaatteessa soveltaa kaikille ydinaktiivisille ytimille, mutta yleisimmin menetelmällä mitataan 1H-ydintä.
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8

Norris, David G. "NMR flow imaging." Thesis, University of Aberdeen, 1986. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU009818.

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The phase-encoded method of NMR flow imaging is examined in detail. The motion of isochromatic groups in the direction of suitably balanced magnetic field gradients will give a phase change in the NMR signal directly proportional to the velocity, acceleration, or higher derivative of position, dependent upon the form of the field gradient. If a simple bipolar pulse is used then the phase change, for isochromats moving with constant velocity, will be proportional to the velocity. If two such pulses are placed back to back then the phase change is proportional to the acceleration. The motion of isochromats in the magnetic field gradients used for imaging will also cause phase changes. These effects are considered, and simple methods of reducing them presented. Phase errors due to main field inhomogeneity are shown to be eliminated by a simple phase difference technique. In this two image data sets having different flow sensitivities are obtained, and the phase difference between them calculated. Velocity images were obtained using this technique, both by the manipulation of the frequency-encoding and selection gradients, and by the insertion of bipolar pulses in the imaging sequence. Acceleration images were also produced by adding double bipolar pulses to the imaging sequence. Both spin-echo and field-echo sequences were used. Field-echo sequences were shown to be superior for high velocities, particularly when the direction of flow is through the slice, otherwise spin-echo sequences were preferred. The Fourier imaging of velocity is also examined, and images presented. This technique is only considered to be useful for projective imaging, where it is shown to have an SNR advantage over established methods. Using two specially designed phantoms the accuracy of all these techniques is shown to be within 5%.
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9

Vuorinen, J. (Jere). "Maaperänäytteiden NMR-analyysi." Bachelor's thesis, University of Oulu, 2018. http://urn.fi/URN:NBN:fi:oulu-201812183292.

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Tässä tutkielmassa olemme kiinnostuneita miten NMR-spektroskopiaa voidaan käyttää maaperänäytteiden tutkimiseen. Maaperässä on erilaisia hiiliyhdisteitä ja niitä voidaan havaita kiinteän aineen 13C NMR-spektroskopialla. Tutkielmassa käydään läpi perinteisen NMR:n ja kiinteän aineen NMR:n perusasioita. Lopuksi perehdytään maaperänäytteiden tutkimiseen.
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10

Sarala, J. (Jouni). "Low field NMR." Bachelor's thesis, University of Oulu, 2019. http://jultika.oulu.fi/Record/nbnfioulu-201907252707.

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Abstract. The subject of this thesis is NMR in low magnetic field. Traditionally NMR instruments utilize a superconducting high field magnet, but recently, compact instruments are getting more common with the use of lower magnetic fields. In this thesis, the basic theory of NMR is explained and the instrumentation and different ways of producing homogeneous magnetic fields are described. An experimental set-up was constructed and tested. The theory of relaxation and dependence of resonance frequency on the magnetic field were demonstrated.
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11

De, Biasi Federico. "Matrix-Assisted NMR." Doctoral thesis, Università degli studi di Padova, 2019. http://hdl.handle.net/11577/3424861.

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During the last decades, the interest of chemistry toward increasingly sophisticated processes has grown exponentially. As a consequence, the evolution of the systems under investigation has been necessarily paired with the development of modern methodologies capable of handling the enormous amount of data stemming from samples of great complexity. Among the many examples in the literature, one of the biggest ongoing challenges is the analysis of mixtures, from reaction crude extracts to biological fluids like blood and urine. Indeed, chromatography has been - and still remains - one of the primary methods adopted to reduce the complexity of a multi-analyte system. Nonetheless, one intrinsic problem of the chromatographic approach is its inability to identify unknown molecules, and hyphenated techniques (mostly based on mass spectroscopy) have been developed just to overcome this stumbling block. On the other hand, Nuclear Magnetic Resonance (NMR) spectroscopy is one of the most powerful techniques for the investigation of organic compounds. NMR exploits an intrinsic property exhibited by some atomic nuclei -- the spin -- to acquire chemical and structural information through well-established experimental protocols, known as pulse sequences. In particular, solution-state NMR can boast a vast ensemble of procedures aimed at collecting detailed data about through bond connectivities (COSY, TOCSY, HSQC,...) or through space proximities (NOESY, ROESY,...). All these information are nothing less than fundamental for the structure determination of unknown compounds. Even tough this makes NMR spectroscopy largely appealing, the acquisition of such extensive information ultimately translates into detecting many signals at once, so that spectra interpretation can become a very challenging task. This is especially true when observing 1H resonances, which display a small dispersion in the frequency domain (about 12 ppm) and spectral crowding becomes consequently a serious problem. Not surprisingly, the situation becomes almost unmanageable when NMR is applied to the assay of mixtures, where the superposition of signals stemming from different species is virtually assured. Certainly, multidimensional NMR techniques can be useful for the interpretation of crowded single-molecule spectra, but they rapidly loose all their advantages as the number of components in the sample increases. As for chromatography, the advent of hybrid techniques like LC-NMR, where LC stands for Liquid Chromatography, has partly circumvented the aforementioned difficulties, yet at the cost of an expensive and dedicated instrumentation. In the context of mixture analysis, matrix-assisted NMR methodologies stand as an alternative to the various hyphenated techniques. They rely on the combination of NMR spectroscopy and an external agent added to the sample, which can be either a molecular or macromolecular species, or even a mesoscopic matrix. The aim of such matrices is to differentiate the signals of the various components, favouring their detection and characterisation. The present work is divided into three independent parts. The first two are dedicated to different subjects of matrix-assisted NMR. In particular, Part I is aimed at the understanding of the physical phenomena underlying signal broadening when a solid, stationary phase is used in Matrix-Assisted Diffusometry (MAD) NMR measurements. Part II focuses on nanoparticle-assisted NMR chemosensing, a technique where monolayer-protected gold nanoparticles are exploited to transfer magnetization to selected classes of analytes by means of the Nuclear Overhauser Effect. In this second part, different nanoparticle-assisted methodologies are presented and analysed, alongside with some strategies aimed at the enhancement of the sensitivity. Part III concerns the complete 1H-NMR characterisation of the atomically precise Au38(SBut)24 gold nanocluster, which can be considered as a prototypical nanoparticle. The Au38 core features four different symmetry-unique and equally populated binding sites for the grafting of the ligands that constitute the coating monolayer. Each binding site shows a distinct pattern of resonances, so that the overall 1H-NMR spectrum of the cluster is the result of the superposition of four independent subspectra. In this case, the full characterisation of the spectrum has been achieved through a combined NMR-MD (Molecular Dynamics) analysis.
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12

Ferrari, Maude, J. P. Mérel, Sébastien Leclerc, Christian Moyne, and Didier Stemmelen. "Study of dispersion by NMR: comparison between NMR measurements and stochastic simulation." Diffusion fundamentals 18 (2013) 11, S. 1-4, 2013. https://ul.qucosa.de/id/qucosa%3A13718.

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Dispersion remains, today, a highly topical subject. Our group has been interested in characterizing this phenomenon by pulsed-field-gradient NMR technique. Direct measurement of the dispersion coefficient can be done with a Pulsed Gradient Spin Echo (PGSE) sequence by assuming that the asymptotic regime is reached. In unsteady state, the propagator formalism is used. To better understand these measurements, the NMR experiment is modeled using a stochastic simulation (random walks) and compared with experimental results. The comparison is made for the simple case of Poiseuille flow in a circular tube (Taylor-Aris dispersion).
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13

Perlo, Juan. "Single sided NMR tomography /." Aachen : Shaker, 2006. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=016031200&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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14

Rourke, David E. "Selective pulses in NMR." Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.259620.

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15

Cheah, Kien Yoo. "NMR studies of catalysis." Thesis, University of Cambridge, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262980.

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16

Veitch, Nigel Charles. "NMR studies of peroxidases." Thesis, University of Oxford, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306025.

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17

Harvey, P. R. "Hyper-fast NMR imaging." Thesis, University of Nottingham, 1991. http://eprints.nottingham.ac.uk/13753/.

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The work presented in this thesis was carried out in the Physics Department at the University of Nottingham between October 1988 and October 1991. It is the original work of the author except where indicated by reference. This thesis describes the continuation of the development of Echo Volumar Imaging (EVI) to facilitate snapshot imaging of a volume within the human body. Variants of the technique which have also been investigated include a spin echo version, SE-EVI, and a zoomed version ZEVI. All formats acquired data in a modulus fashion in times ranging from 64 ms to 120 ms. Hardware limitations have restricted the image matrix size to 64 x 32 x 8 voxels and prompted the employment of more efficient gradient driver circuitry. A multi-mode resonant gradient circuit is described for use in both Echo Planar Imaging (EPI) and EVI. The circuit behaves in an overall resonant manner but at a fixed number of discrete frequencies. By choosing the number of resonant modes, the circuit can be used to generate approximations to a square wave or trapezoidal waveform. Because of the energy conserving nature of the circuit design much faster current rise times can be achieved with a given amplifier and gradient coil. The multi-mode gradient driver circuit was utilized both for planar imaging and to investigate the effect of rapidly modulated magnetic fields on the human body. A simple neural stimulation model is used to evaluate the stimulation threshold current density for a variety of magnetically induced waveforms and for sinusoidal stimulation as a function of frequency. Experimental results correlate well with the model showing that for short times, contrary to the widely held view, neural stimulation is independent of the magnetic field switching rate dB / dt, but depends on the final magnetic field value.
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18

Furby, Michael Ian Charles. "NMR of liquid crystals." Thesis, University of Southampton, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263471.

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19

Welch, John. "Multidimensional in vivo NMR." Thesis, University of Oxford, 2001. http://ora.ox.ac.uk/objects/uuid:876ed795-9e23-4d53-a407-0a29f7c9ea21.

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A proton nuclear magnetic resonance spectrum of the brain in vivo contains peaks from every proton-containing molecule in the brain. Sensitivity limitations mean that only those molecules present at concentrations of at least a few millimolar are detectable in a reasonable period of time; this still leaves many important molecules such as amino acids and other small metabolites. Most of their resonance frequencies fall in the region between 1.0 and 4.5 p.p.m. A typical linewidth in vivo is about 0.05 p.p.m., so the number of distinct peaks observable is restricted. The use of two-dimensional NMR techniques such as COSY can spread peaks out into a second dimension enabling otherwise overlapping peaks to be resolved. This thesis describes the development, testing and application of two such 2D NMR pulse sequences, dubbed ISIS-COSY and ISIS-JRES. They are based on an existing magnetisation localisation sequence and excite detected magnetisation in a manner analogous to the high-resolution sequences COSY and 2D J-resolved spectroscopy. A method for quantifying the metabolites visible in an ISIS-COSY spectrum from their cross-peak intensities is described, and results presented from both control rat brains and those of animals treated with vigabatrin, an inhibitor of GABA-transaminase that has the effect of increasing brain γ-amino butyric acid (GABA) levels. Further applications mentioned are in the study of neutrophil-infiltrated rat brain and adaptation of the ISIS-COSY technique for human use.
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20

Jaroszkiewicz, E. M. "NMR of entangled polymers." Thesis, University of Nottingham, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.371126.

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21

McJury, Mark. "NMR microscopy at 500MHz." Thesis, University of Nottingham, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293694.

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22

Ghaoui, Nora. "Process applications of NMR." Thesis, University of Cambridge, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.621156.

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23

Bendell, David. "NMR of mycoprotein systems." Thesis, University of Sunderland, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284753.

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24

Bushell, Mary-Clare. "Intermediate scale NMR imaging." Thesis, University of Surrey, 1985. http://epubs.surrey.ac.uk/847283/.

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The design, construction and calibration of an intermediate scale NMR imaging system is described. The system is based on a 7" diameter, room temperature bore superconducting magnet at a field of 0.4T. Using selective excitation and projection reconstruction techniques, the production of density, spin-lattice and spin-spin relaxation weighted images has been achieved. An investigation of the feasibility of in-vivo tissue characterisation using NMR parameters has been carried out. Tissue characterisation using healthy animals of different ages, sex and species has shown that characterisation with the NMR parameters of T1** and T2** is feasible on a given system, where 1/T1** and 1/T2** are the spin-lattice and spin-spin relaxation rates calculated from the images assuming these rates to be mono-exponential. It is shown that the scatter in results which previously was believed by other authors to be due to biological variation is in fact due to experimentation and instrumentation, and that the biological limit has yet to be reached. The successful employment of quantitative characterisation in the observation and monitoring of diseased states is illustrated by two examples. The first shows the growth of a tumour and the second uses T1* to observe the effect of toxic drugs on the kidney. In the latter case, little evidence of damage was visible on the image. Following characterisation, it is demonstrated that it is possible to optimise an imaging sequence by careful selection of the timing parameters. Optimisation of the sequences used in this work gave an increase of upto a factor of two in the signal-to-noise ratio and increased the accuracy of the relaxation rate evaluation. Finally, a technique for obtaining a map of the spatial distribution of the molecular translational diffusion coefficient together with perfusion and flow information has been developed. These parameters may well enhance the contrast as well as providing new information on the biological system.
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25

Gerhalter, Teresa. "Characterization of the dystrophic muscle by ²³Na NMR and ¹H NMR T₂ spectrum." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS219/document.

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Le but de la thèse était d'étudier la sensibilité de nouveaux biomarqueurs RMN visant à quantifier les changements pathologiques dans le muscle dystrophique. La dystrophie musculaire (DM) désigne un groupe hétérogène de maladies avec une atrophie musculaire progressive associée à un état de faiblesse. Elle est caractérisée par des degrés variables de nécrose, de régénération, de troubles de l'homéostasie ionique, d'inflammation chronique et finalement par le remplacement des muscles par du tissu fibro-graisseux. Mon objectif était d’évaluer la RMN du ²³Na et les techniques avancées de mesure du temps de relaxation transversal ¹H (T₂) en tant que des biomarqueurs sensibles et précoces. La RMN du ²³Na mesure les concentrations de sodium étroitement contrôlées et donne sa distribution dans le tissu. Cette information peut être utilisée pour évaluer l'homéostasie ionique et l'intégrité cellulaire. Cependant, la concentration in vivo en ²³Na est faible, la RMN du ²³Na souffre donc d'une faible sensibilité par rapport à ¹H. L’altération du T₂ ¹H du muscle, communément interprétée comme un indicateur de l'activité de la maladie, est liée à une variété d’événements non-spécifiques tels que l'œdème, l'inflammation ou la nécrose, qui précèdent le remplacement musculaire par la graisse. Des protocoles comprenant diverses méthodes de RMN du ²³Na et de ¹H T₂ ont été mis en œuvre pour évaluer les tissus musculaires squelettiques sains et dystrophiques sur des modèles animaux et sur patients. Ce travail fournit des preuves que la RMN du ²³Na pourrait offrir un biomarqueur sensible capable de surveiller l'altération spécifique du muscle dystrophique à un stade très précoce
The aim of the thesis is to investigate the sensitivity of novel NMR outcome measures (OM) aiming to quantify pathological changes in the dystrophic muscle. Muscular dystrophy (MD) refers to a heterogeneous group of diseases with progressive muscle wasting and associated weakness characterized by variable degrees of necrosis, regeneration, ionic homeostasis disturbances, chronic inflammation, and, ultimately, resulting in the replacement of muscles by fibro-fatty tissue. My focus was on the evaluation of ²³Na NMR and advanced ¹H transverse relaxation time (T₂) techniques as early, sensitive OM. ²³Na NMR measures the tightly controlled sodium concentrations and distribution in skeletal muscle tissue. This biophysical information can be used to assess ion homeostasis and cell integrity. However, ²³Na NMR suffers from a low sensitivity and in vivo concentration compared to ¹H. Alterations in the muscle ¹H T₂, commonly interpreted as an indicator of disease activity, are linked to a variety of non-specific events like oedema, inflammation, or necrosis that precede the actual muscle replacement by fat. Protocols including different ²³Na NMR and ¹H T₂ methods were implemented to evaluate healthy and dystrophic skeletal muscle tissues of animal models and patients. This work provides evidence that ²³Na NMR could offer a sensitive outcome measure able to monitor specific alteration of the dystrophic muscle at a very early stage
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Francke, Volkhard. "Festkörper-NMR-, 129Xe-NMR- und BET-Studien an adsorbierten benzoiden Verbindungen auf mesoporösen Materialien." [S.l.] : [s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=964532301.

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Wiesmath, Anette. "NMR methods for strongly inhomogeneous magnetic fields: application on elastomers using the NMR-mouse." [S.l.] : [s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=96487721X.

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Hartl, Rainer. "Berechnung der NMR-Struktur der PPARgamma-LBD und Hochdruck-NMR-Messungen an HPr I14A." kostenfrei, 2008. http://www.opus-bayern.de/uni-regensburg/volltexte/2009/1025/.

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29

Uluca, Boran [Verfasser]. "Solid-State NMR and DNP-Enhanced NMR Studies on Intrinsically Disordered Proteins / Boran Uluca." Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2018. http://d-nb.info/1164763237/34.

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30

Dvoyashkina, Nina, Dieter Freude, Christopher F. Seidler, Michael Wark, and Jürgen Haase. "Composite fuel cell materials studied by MAS PFG NMR diffusometry and MAS NMR spectroscopy." Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-198097.

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31

Dvoyashkina, Nina, Dieter Freude, Christopher F. Seidler, Michael Wark, and Jürgen Haase. "Composite fuel cell materials studied by MAS PFG NMR diffusometry and MAS NMR spectroscopy." Diffusion fundamentals 24 (2015) 12, S. 1, 2015. https://ul.qucosa.de/id/qucosa%3A14526.

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32

Palfreyman, Stuart A. "Sonically induced narrowing of the NMR spectra of solids and other novel NMR techniques." Thesis, Aston University, 1996. http://publications.aston.ac.uk/9610/.

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A typical liquid state NMR spectrum is composed of a number of discrete absorptions which can be readily interpreted to yield detailed information about the chemical environment of the nuclei found within the sample. The same cannot be said about the spectra of solid samples. For these the absorptions are typically broad, featureless and yield little information directly. This situation may be further exacerbated by the characteristically long T1 values of nuclei bound within a solid lattice which, consequently, require long inter-sequence delays that necessitate lengthy experiments. This work attempts to address both of these inherent problems. Classically, the resolution of the broad-line spectra of solids into discrete resonances has been achieved by imparting to the sample coherent rotation about specific axes in relation to the polarising magnetic field, as implemented in the magic-angle spinning (MAS) [1], dynamic angle spinning (DAS) [2] and double rotation (DOR) [3] NMR experiments. Recently, an alternative method, sonically induced narrowing of the NMR spectra of solids (SINNMR) [4], has been reported which yields the same well resolved solid-state spectra as the classic solid-state NMR experiments, but which achieves the resolution of the broad-line spectra through the promotion of incoherent motion in a suspension of solid particles. The first part of this work examines SINNMR and, in particular, concentrates on ultrasonically induced evaluation, a phenomenon which is thought to be essential to the incoherent averaging mechanism. The second part of this work extends the principle of incoherent motion, implicit in SINNMR, to a new genre of particulate systems, air fluidized beds, and examines the feasibility of such systems to provide well resolved solid state NMR spectra. Samples of trisodium phosphate dodecahydrate and of aluminium granules are examined using the new method with partially resolved spectra being reported in the case of the latter.
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33

Schmid, Michael. "NMR investigations on alkali intercalated carbon nanotubes." [S.l. : s.n.], 2005. http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-25673.

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34

Khajeh, Maryam. "Kinetic measurements using time-resolved NMR spectroscopy." Thesis, University of Manchester, 2010. https://www.research.manchester.ac.uk/portal/en/theses/kinetic-measurements-using-timeresolved-nmr-spectroscopy(aae85bb3-de19-450a-96ab-50e2dfd89da7).html.

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Many thousands of pounds are spent every year by pharmaceutical companies on understanding the mechanisms and kinetics of chemical reactions involved in drug discovery and production. NMR spectroscopy is often at the core of these studies as it is a powerful, non-destructive method for structure elucidation. As such investigations can be time-consuming and cost-inefficient, AstraZeneca, the project sponsor, is interested in more efficient methods for studying the kinetics of pharmaceutical reactions. In this work a number of different techniques have been devised, studied, and implemented to study the kinetics of chemical reactions by time-resolved NMR spectroscopy, in which every species in a reaction can be monitored simultaneously. These novel techniques allow the study of reactions which are difficult or impossible to study by conventional NMR methods (such as heterogeneous reactions), or which are complicated by having overlapping signals. It is possible to monitor the kinetics of a reaction very simply by acquiring a series of 1H spectra, and obtaining the integrals of the signals by least squares fitting. This technique has been used for kinetic studies of static and on-flow reactions. In the static systems the reaction mixture was placed in the normal NMR tube in the magnet, while in the flow system the reaction mixture was placed outside of the magnet, and the solution flowed through an NMR tube placed in the magnet. The novel flow system designed, constructed and tested here has been used for kinetic studies of illustrative homogeneous and heterogeneous reactions, and is suitable for use in a wide range of NMR instrumentation. Kinetic studies have also been carried out by acquiring a series of DOSY datasets, analysing the results using the multi-way method PARAFAC (PARAllel FACtor analysis). A series of DOSY datasets contains multivariate information on spectrum, time evolution and diffusion. Without providing any predetermined model, the data can be decomposed by PARAFAC to yield the spectrum, kinetics, and diffusion profiles for each of the components. It has also been shown that PARAFAC is remarkably robust to low signal-to-noise ratio data, significantly below the level at which conventional methods would fail.
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35

Boero, Giovanni. "Integrated NMR probe for magnetometry /." [S.l.] : [s.n.], 2000. http://library.epfl.ch/theses/?nr=2211.

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36

Schick, Martin Christopher. "High pressure NMR of ubiquitin /." Zürich, 1998. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=12586.

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37

Kaufmann, Ilja. "Funktionelle NMR-Mikroskopie an Pflanzenwurzeln." kostenfrei, 2008. http://www.opus-bayern.de/uni-wuerzburg/volltexte/2009/3415/.

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38

Titze, Andreas. "87Rb-NMR-Untersuchungen an Trirubidiumhydrogendisulfat." [S.l. : s.n.], 2000. http://ArchiMeD.uni-mainz.de/pub/2000/0113/diss.pdf.

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39

Gröger, Adriane. "NMR-spektroskopische Untersuchungen von Proteinen." [S.l.] : [s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=962026921.

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40

Rademacher, Martin. "NMR-spektroskopische Untersuchungen an Fettsäurebindungsproteinen." [S.l.] : [s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=964224984.

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41

Nikkhou, Aski Sahar. "NMR Studies of Inclusion Compounds." Doctoral thesis, Stockholm University, Department of Physical, Inorganic and Structural Chemistry, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-8223.

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This thesis presents the application of some of the NMR methods in studying host-guest complexes, mainly in solution. The general focus of the work is on investigating the reorientational dynamics of some small molecules that are bound inside cavities of larger moieties. In the current work, these moieties belong to two groups: cryptophanes and cyclodextrins. Depending on the structure of the cavities, properties of the guest molecules and the formed complexes vary. Chloroform and dichloromethane are in slow exchange between the cage-like cavity of the cryptophanes and the solvent, on the chemical shift time scale, whereas adamantanecarboxylic acid, quinuclidine and 1,7-heptanediol in complex with cyclodextrins are examples of fast exchange. Kinetics and thermodynamics of complexation are studied by measuring exchange rates and translational self-diffusion coefficients by means of 1-dimenssional exchange spectroscopy and pulsed-field gradient (PFG) NMR methods, respectively. The association constants, calculated using the above information give estimates of the thermodynamic stability of the complexes. Carbon-13 spin relaxation data were obtained using conventional relaxation experiments, such as inversion recovery and dynamic NOE, and in some cases HSQC-type (Hetereonuclear Single Quantum Correlation Spectroscopy) experiments. Motional parameters for the free and bound guest, and the host molecules were extracted using different motional models, such as Lipari-Szabo, axially symmetric rigid body, and Clore models. Comparing the overall correlation times and the order parameters of the free and bound guest with the overall correlation time of the host molecule one can estimate the degree of the motional restriction, brought by the complexation, and the coupling between the motion of the bound guest and the reorientation of the host molecule. In one case, the guest motions were also investigated inside the cavities of a solid host material.

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42

Dücker, Eibe Behrend. "Enhancement Strategies in NMR Spectroscopy." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2018. http://hdl.handle.net/11858/00-1735-0000-002E-E3E4-9.

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43

Wang, Mingfei. "Moderne Festkörper-NMR an Funktionspolymeren." Aachen : Shaker, 2004. http://deposit.d-nb.de/cgi-bin/dokserv?idn=972768122.

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44

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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45

McIntyre, D. J. O. "NMR microscopy at 9.4 Tesla." Thesis, University of Cambridge, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386215.

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46

Harvey, Timothy Scott. "Protein structure from NMR data." Thesis, University of Oxford, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305965.

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47

Spickett, Corinne Michelle. "NMR studies of cellular bioenergetics." Thesis, University of Oxford, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.257961.

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48

Lumb, Kevin J. "NMR studies of lysozyme complexes." Thesis, University of Oxford, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.291521.

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49

Hughes, Colan Evan. "New techniques in NMR spectroscopy." Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297524.

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50

Carr, M. D. "NMR studies of oxidative phosphorylation." Thesis, University of Oxford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382584.

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