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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Nuclear Magnetic Resonance Investigation of the Interaction of Heme Binding Proteins with SnIVprotoporphyrin IX and Heme: Structure and Conformational Changes of Myoglobin and Hemopexin

Deeb, Ruba Saba 01 January 1993 (has links)
Tin protoporphyrin IX (SnPP) is currently under investigation for the treatment of hyperbilirubinemia. The study of the complex between SnPP and equine myoglobin (EqMb) by ¹H and ¹¹⁹Sn nuclear magnetic resonance spectroscopy (NMR) can be viewed as a general model for SnPP interaction with hemoproteins. The complex formed from the equilibrium mixture of SnPP and EqMb, SnPP•EqMb, was found to have essentially the same porphyrin-binding pocket as EqMbCO and SwMbCO, including the same porphyrin orientation in the major form of the two species. ¹¹⁹Sn NMR spectroscopy was used to demonstrate that the proximal His(93)F8-metal coordination is likely to be intact in SnPP•EqMb. Minor shifts in the side chain positions of some of the residues were observed, possibly reflecting the presence of water in the sixth coordination site. SnPP•EqMb appears to be stable; it persists at room temperature for weeks and exhibits very slow exchange rates (²Hfor ¹H) for a large number of amide protons in the pH range 7-9. Events during the reconstitution of apomyoglobin (apoMb) with SnPP were probed. Thus interactions between tin(IV)protoporphyrin IX (SnPP) and equine apoMb, and between tin(IV) protoporphyrin IX dimers (SnPP)₂ and apoMb were observed by ¹H NMR and optical spectroscopic techniques. The products and intermediates observed in this situation were related to the equilibrium structure of SnPP•EqMb. Reactions of apoEqMb with SnPP and (SnPP)₂ produce different intermediates, although the final product, SnPP•EqMb, is the same for each. An intermediate observed for the reaction of SnPP with apoEqMb at pH 10 is in exchange with free SnPP, with the observed rate constant Koff ~ 1 sˉ¹; meso-proton resonances were assigned for this intermediate by correlation to SnPP resonances via chemical exchange. The intermediate observed for the reaction of (SnPP)₂ with apoEqMb at neutral pH produces another species which may be the alternate porphyrin-insertion isomer arising from a 180° rotation about the α,γ-meso axis of the porphyrin. Although optical absorbance spectroscopy of the Soret region shows evidence for the reaction of SnPP and (SnPP)₂ with apoMb, only in combination with ¹H NMR are the various processes assigned. T his study of the complex SnPP•EqMb facilitated the investigation of the more complex heme binding protein, hemopexin (Hx). Proton NMR spectroscopy is reported for the first time for the hemin complex of hemopexin, a serum protein that binds heme exceptionally tightly. Hx from cow, rat, rabbit, and human was isolated, and data for the protein were reported. Heme-bound Hx has spectral characteristics for being low-spin, paramagnetic. Deuterium isotope labels reveal the positions for the heme 1-, 3-, and 8-methyls; the 5-methyl lies in the -5 to 12 ppm region. Furthermore, two-dimensional nuclear Overhauser effect spectroscopy was used to locate other heme periphery protons, including those from the 2-vinyl and the 7-propionate. Upfield resonances are identified that are very strongly relaxed, and so are assigned to protons on the axial ligands. The information reported here contributes to the understanding of Hx as an antioxidant at the cellular level.
82

N.M.R. spectroscopic and chemical studies on the distribution of substituent groups in hydroxypropylcellulose

Lee, Dae-Sil. January 1982 (has links)
No description available.
83

Part 1. Synthesis of stable-isotope labeled amino acids. Part 2. Synthesis of mechanistic probes of retinoid action /

Barnett, Derek W. January 2002 (has links)
No description available.
84

New developments in chromatographic NMR

Lucena Alcalde, Guillermo January 2018 (has links)
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.
85

A comparative study with of the NMR spectra of Sulphur 12CH prepared using Hahnemannian method and sonication

Marsh-Brown, Scott January 2016 (has links)
Submitted in partial compliance with the requirements of the Master’s Degree in Technology: Homoeopathy, Durban University of Technology, Durban, South Africa, 2016. / Aim The aim of this study was to compare the nuclear magnetic resonance spectra of Sulphur 12c samples produced by the traditional Hahnemannian method with Sulphur 12c samples produced using sonication as an alternative method of agitation. Sonication, while not widely employed as an agitating technique in the homoeopathic potentisation process, is a highly effective agitation process which produces effects on liquids that closely resemble the effect of traditional Hahnemannian hand succussion (Bhattacharyya et al. 2008). Thus, this study sought to reveal whether or not homoeopathic remedies produced by sonication bore a close enough physicochemical resemblance to traditional hand succussed remedies to be considered as a viable equivalent. Methodology Five sample groups were manufactured for analysis, all by means of serial dilution at the centesimal ratio (1:100) to the 12c potency, and with agitation between dilution levels where applicable. Three of the sample groups were experimental, namely the Sulphur 12c Hahnemannian, Sulphur 12c sonicated and Sulphur 12c both (succussion and sonication). The Sulphur 12c Hahnemannian samples were produced by hand according to the German Homoeopathic Pharmacopoeia (Benyunes 2005), which includes an agitation phase of 10 hand succussions. Sonicated samples were produced according to the Hahnemannian method as far as possible, however the agitation phase consisted of 30 seconds of sonication in a sonication bath at 40Hz in accordance with related studies (Sukul, Sinhabau, and Sukul 1999: 58-59; Sukul et al. 2001a: 187). Sulphur 12c both (succussion and sonication) samples underwent ten hand succussions and 30 seconds of sonication at 40Hz between dilution levels. Two of the sample groups were controls, namely Sulphur 12c unagitated and Lactose 12c unagitated, neither of which underwent agitation between dilution phases but were otherwise produced according to the German Homoeopathic Pharmacopoeia specification (Benyunes 2005). All samples were raised to the 12c potency level in 87% alcohol from a 3CH triturate. The Lactose 12c unagitated control was derived from a 3CH triturate of lactose, while the other samples were all derived from a 3CH triturate of Sulphur. The sample groups were sent for nuclear magnetic resonance (NMR) spectroscopy at the Department of Chemistry at Stellenbosch University. The NMR device used was the Varian UnityInova 600 NMR Spectrometer ®, with a Deuterated DMSO insert added as an instrument frequency lock. Samples were drawn and analysed by Dr D.J. Brand. One sample was drawn from each sample group. The chemical shift and relative integration values for the OH, H2O, CH2, and CH3 peaks of the NMR spectra were captured and tabulated using Microsoft Excel© 2013. The statistical analysis was performed with the aid of SPSS Version 22. The chemical shift and relative integration values for the H2O, OH, CH2 and CH3 peaks were used in the statistical analysis. The Kruskal-Wallis method was performed for the five sample groups to ascertain whether or not a statistically significant difference existed between the five sample groups. Comparisons between individual paired groups were conducted by means of the non-parametric Mann-Whitney test. The significance interval was set at α = Results The chemical shift values of the CH2 peaks of the samples showed a clear similarity between the samples produced by Hahnemannian hand succussion, sonication and both (succussion and sonication) as well as a clear difference between these three samples and the two controls. The relative integration values, however, showed no clear trends in support of or detracting from the hypotheses. Conclusion In terms of the CH2 peak chemical shift values it can be concluded that distinct similarities exist between 12c potency level of Sulphur produced by Hahnemannian hand succussion and sonication, and that the two methods of agitation produce similar structural properties in samples of the 12c potency level. Furthermore in terms of the chemical shift values, succussion and sonication develop remedies that are distinct from unagitated remedies of equivalent potency level. Thus, these findings support the use of sonication as a potentially viable alternative to hand succussion as a method of agitation in the potentisation process. Further studies need to be conducted however, with the inclusion of a greater variety of potency levels in order to possibly reveal more trends in terms of the relative integration values as these values were inconclusive in this study. / M
86

A multinuclear magnetic resonance spectroscopy study of E/Z configurational isomers of unsymmetrical N-alkyl-N-alkyl(aryl)-N'-acylthioureas of platinum(II) complexes

Mtongana, Sibusiso 12 1900 (has links)
Dissertation (PhD)--University of Stellenbosch, 2006. / ENGLISH ABSTRACT: The partial double bond character of the carbon-nitrogen bond of the (S)C-NRR’ moiety results in unsymmetrical dialkyl-substituted N-alkyl-N-alkyl(aryl)-N’-acylthioureas, R”C(O)NHC(S)NRR’ (HL) displaying E,Z configurational isomerism in solution. The isomerism manifests itself by the duplication of resonances of the N-alkyl groups in the 1H and 13C NMR spectra. In one class of these ligands where R and R’ groups are non-equivalent alkyl groups the isomerism is easily observable at 298 K in chloroform. In the other class where R’ is still an alkyl group and R is a para-substituted phenyl group the isomerism is only observable at much lower temperatures due to a lower barrier to rotation around the (S)C-N(alkyl)(para-X-Ph) bond (X = O-CH3, H and NO2). The electron-withdrawing nature of the nitro group in N-methyl-N-(4-nitro-phenyl)-N’-2,2-dimethylpropanoylthiourea, HL3A and N-pentyl-N- (4-nitro-phenyl)-N’-2,2-dimethylpropanoylthiourea, HL3D result in the E,Z isomerism of these ligands not observable even at 198 K in dichloromethane. The distribution of E and Z isomers of the unbound ligands vary depending on these R and R’ groups. Several E isomers of these ligands have been isolated and structurally characterised and the (S)C-NRR’ bond falls in the range [1.343(3) – 1.329(3) Å] which shorter than the average C-N single bond of 1.472(5) Å. The E,Z configurational isomerism in the unbound ligands is passed on to the Pt(II) chelates derived from these ligands. The presence of cis-[Pt(ZZ-L-S,O)2], cis-[Pt(EZ-L-S,O)2] and cis-[Pt(EE-L-S,O)2] is readily observable by means of 195Pt NMR spectroscopy which shows three well resolved resonances, and this can be confirmed by 1H and 13C NMR spectra of these complexes. The 195Pt nuclei are spatially linked to the 13C nuclei, four bonds away resulting in 4J(195Pt-13C) couplings with N-CH2- or N-CH3 carbons in a W pathway. The 195Pt NMR spectra are also linked to N-CH2- or N-CH3 proton resonances by means of the ZZ, EZ and EE isomer distributions. Assignment of these configurational isomers was then achieved by means of a combination of low magnetic field 13C NMR spectra and high-resolution gHSQC (1H/13C) NMR experiments. 1H NMR rotational dynamics study showed that the barrier to rotation, ΔG≠, around the (S)C-N(Me)(para-X-Ph) bond in cis-bis(N-methyl-N-(4-methoxy-phenyl)-N’-2,2-dimethylpropanoylthioureato)platinum(II), cis-[Pt(L1AS, O)2]; cis-bis(N-methyl-N-phenyl-N’-2,2-dimethylpropanoylthioureato)platinum(II), cis-[Pt(L2A-S,O)2] and cisbis( N-methyl-N-(4-nitro-phenyl)-N’-2,2-dimethylpropanoylthioureato)platinum(II), cis-[Pt(L3A-S,O)2] complexes was observed to follow the order: (electron-withdrawing group) NO2 < H < (electron-donating group) O-CH3. The ZZ isomer was observed to be favoured over the EZ and EE isomers in this order of the para-substituent on the Nphenyl group. The 1H dynamic NMR trends about the barrier to rotation, ΔG≠, around the (S)C-N(Me)(para-X-Ph) bond were also complemented by DFT linear transit calculations. The isomer distributions were also influenced by solvent polarity and the temperature at which the distributions are determined apart from the electronic influence of the para-substituent of the N-phenyl group. The ZZ, EZ and EE isomers of complexes derived from N-alkyl-N-(para-X-Ph)-N’-acylthioureas with varying Nalkyl substituent (methyl, isopropyl, cyclohexyl and n-pentyl) were determined from the 195Pt NMR spectra which were measured under identical conditions. The ZZ isomer was observed to be favoured over the EZ and EE isomers upon methyl group substitution with a bulkier alkyl group in the order: methyl < isopropyl < cyclohexyl < n-pentyl. Qualitatively it has been shown that a bulkier N-pentyl group increases the barrier to rotation around the (S)CN( alkyl)(para-X-Ph) bond over the N-methyl group and this leads to higher concentrations of the ZZ isomer over the EZ and EE isomers. The combined effects of the electron-donating substituent (X = O-CH3) on the N-(para-X-Ph) group and the bulkier N-alkyl group (n-pentyl) result in highest ZZ concentration (76 %) over EZ and EE isomers in the complex cis-bis(N-pentyl-N-(4-methoxy-phenyl)-N’-2,2-dimethylpropanoylthioureato)platinum(II), cis-[Pt(L1DS, O)2]. The lowest concentration ZZ (27 %) is obtained in the complex cis-bis(N-methyl-N-(4-nitro-phenyl)-N’-2,2- dimethylpropanoylthioureato)platinum(II), cis-[Pt(L3A-S,O)2] when the coordinated ligand has both N-methyl group and N-(4-nitro-Ph) group which both lower the barrier to rotation around the (S)C-N(alkyl)(para-X-Ph) bond. A crystal of the complex cis-bis(N-pentyl-N-(4-methoxy-phenyl)-N’-2,2-dimethylpropanoylthioureato)platinum(II), cis-[Pt(L1D-S,O)2] has been isolated and structurally characterised and was shown to be in the ZZ configuration, which is the major component (76 %) in chloroform. This is the first example of Pt(II) chelates with asymmetrically disubstituted ligands to be reported. / AFRIKAANSE OPSOMMING: Die gedeeltelike dubbelbinding karakter van die koolstof-stikstof-binding van die (S)C-NRR’-moieteit lei tot onsimmetriese dialkiel-gesubstitueerde N,N-dialkiel-N’-asieltioureums, R”C(O)NHC(S)NRR’ (HL) wat E,Zkonfigurasionele isomerie in oplossing besit. Die isomerie is sigbaar in die verdubbelling van die seine van die Nalkielgroepe in die 1H- en 13C-KMR spektra. In een so klas ligande waar R- en R’-groepe nie-ekwivalente alkielgroepe is, is isomerie duidelik sigbaar by 298 K in chloroform. In die ander klas waar R’ steeds ’n alkielgroep is, en R ’n para-gesubstitueerde feniel groep, is die isomerie alleenlik sigbaar by baie laer temperature as gevolg van ’n laer rotasieversperring om die (S)C-N(alkiel)(para-X-Ph)-binding (X = O-CH3, H and NO2). Die elektrononttrekkende aard van die nitrogroep in N-metiel-N-(4-nitrofeniel)-N’-(2,2-dimetielpropanoïel)tioüreum, HL3A en N-(4-nitrofenyl)-N-pentiel-N’-(2,2-dimetielpropanoïel)tioüreum, HL3D lei daartoe dat die E,Z-isomerie van die ligande nie eers by 198 K in dichlorometaan waargeneem word nie. Die verspreiding van die E en Z isomere verskil na gelang van die R en R’ groepe. Verskeie E-isomere van hierdie ligande is geïsoleer en struktureel gekarakteriseer en die (S)C-NRR’-bindingslengte is in ‘n gebied [1.343(3) – 1.329(3) Å] wat korter is as die gemiddelde C-N-enkelbindingslengte van 1.472(5) Å. Die Pt(II) chelate wat afgelei is van die ligande is blootgestel aan die E,Z-konfigurasie isomere van die ongebinde ligande. Die teenwoordigheid van cis-[Pt(ZZ-L-S,O)2], cis-[Pt(EZ-L-S,O)2] en cis-[Pt(EE-L-S,O)2] is maklik waarneembaar deur middel van 195Pt-KMR-spektroskopy wat drie goed geresolueerde seine toon, en dit kan bevestig word met 1H- en 13C-KMR spectra van hierdie komplekse. Die 195Pt kerne is ruimtelik geskakel met die 13C kerne deur vier bindings wat aanleiding gee tot 4J(195Pt-13C)-koppelings met N-CH2- of N-CH3-koolstofatome in ‘n Wkonformasie. Die 195Pt KMR spektra word geskakel met die N-CH2- of N-CH3-protonresonansies in al drie die moontlike ZZ, EZ en EE kompleksisomere. Toekenning van die konfigurasionele isomere is dan bewerkstellig deur middel van ‘n kombinasie van lae magneetveld 13C-KMR spectra en hoë resolusie gHSQC (1H/13C) KMR experimente. 1H-KMR-rotasiedinamiek studie toon dat die rotasiegrens, ΔG≠, om die (S)C-N(Me)(para-X-Ph)-binding in cisbis( N-metiel-N-(4-metoksifeniel)-N’-2,2-dimetielpropanoïeltioureato)platinum(II), cis-[Pt(L1A-S,O)2]; cis-bis(Nfeniel- N-metiel-N’-2,2-dimetielpropanoïeltioureato)platinum(II), cis-[Pt(L2A-S,O)2] en cis-bis(N-metiel-N-(4- nitrofeniel)-N’-2,2-dimetielpropanoïeltioureato)platinum(II), cis-[Pt(L3A-S,O)2] komplekse was met die volgende orde bepaal: (elektron-ontrekkende groep) NO2 < H < (elektron-skenkende groep) O-CH3. Die ZZ-isomeer blyk by voorkeur te vorm bo die EZ- en EE-isomere in dieselfde orde as hierbo wat betref para-substituent aan die Nfenielgroep. Die 1H dinamiese KMR tendencies ten opsigte van die rotasiegrens, ΔG≠, om die (S)C-N(Me)(para-XPh)- binding is gekomplimenteer met DFT-linêre organgs berekeninge. Die isomer verspreidings blyk ook beïnvloed te word deur die oplosmiddel polariteit en die temperatuur waarby die verspreidings bepaal is, buiten die elektroniese invloed van die para-substituent aan die N-fenielgroep. Die ZZ, EZ en EE isomeer verspreiding van komplekse wat afgelei is van N-alkiel-N-(para-X-Ph)-N’-asieltioureums met veranderlike N-alkiel substituente (metiel, isopropyl, sikloheksiel, en n-pentiel) is vasgestel deur middel van die 195Pt KMR wat opgeneem is onder identiese kondisies. Die ZZ-isomeer blyk die verkose isomeer te wees bo die EZen EE-isomere waar die metiel substituent vervang word met ‘n groter alkiel groep in die orde van: metiel < isopropiel < sikloheksiel < n-pentiel. Dit is kwalitatief getoon dat die groter N-pentielgroep die rotasiegrens verhoog vir rotasie om die (S)C-N(alkiel)(para-X-Ph)-binding bo dié van die N-metielgroep wat aanleiding gee tot hoër konsentrasies van die ZZ-isomeer relatief tot die EZ- en EE-isomere. Die gekombineerde uitwerking van die electron-skenkende substituent (O-CH3) op die N-(para-X-Ph)-groep en die groter N-alkiel groep (n-pentiel) gee aanleiding tot die hoogste ZZ-konsentrasie (76%) bo EZ- en EE-isomere in die kompleks cis-bis(N-pentiel-N-(4- metoksifeniel)-N’-2,2-dimetielpropanoïeltioureato)platinum(II), cis-[Pt(L1D-S,O)2]. Die laagste konsentrasie ZZ (27%) is verkry in die kompleks cis-bis(N-metiel-N-(4-nitrofeniel)-N’-2,2-dimetielpropanoïel)tioureato)platinum(II), cis-[Pt(L3A-S,O)2] waar die gekoördineerde ligand beide die N-metiel- sowel as die N-(4-nitro-Ph)-groep, wat albei die rotasiegrens van die (S)C-N(alkiel)(para-X-Ph)-binding verlaag. ‘n Kristalstruktuur van die kompleks cis-bis(N-pentiel-N-(4-metoksifeniel)-N’-2,2-dimetielpropanoïeltioureato) platinum(II), cis-[Pt(L1D-S,O)2] wat geïsoleer is, is struktureel gekarakteriseer en is in die ZZ-konfigurasie, wat die hoofkomponent (76%) is in chloroform. Hierdie is die eerste voorbeeld van Pt(II) chelate met asimmetriese digesubstitueerde ligande om geraporteer te word.
87

NMR spectroscopic and kinetic studies on secondary enamines and unstable dihydroxy derivatives of heterocyclic compounds

吳振平, Wu, Zhen-ping. January 1987 (has links)
published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
88

A comparison of Hahnemannian and Korsakovian potentising methods using Nuclear Magnetic Resonance Spectroscopy

Davies,Troy Murray January 2001 (has links)
Dissertation submitted in partial compliance with the requirements for the Master's Degree in Technology: Homoeopathy, Technikon Natal, 2001. / The purpose of this study was to analyse and compare the NMR spectra ofa homoeopathic remedy (in this case Natrum muriaticum was used for its easy solubility and purity), that was prepared in the classical single vial Hahnemannian method, and also the widely used multi-vial Korsakovian method. Comparison was made in terms of the chemical shift (8) and relative integration values of the CH3, CH2, H20, and OH signals. A control was employed for both methods. The only difference between control and test remedies was the actual inclusion ofNatrum muriaticum in the latter, and the same weight of solvent as solute in the former. Comparison was made between both test methods, between test and control, and between the two controls. It was hypothesized that the method of dilution plays an important part in the potentisation process, and thus becomes part of the remedy's information content. The evolution of distinct physicochemical identities was hypothesized to occur specific to each method in ascending potency levels. Differences were therefore also hypothesized to exist between both methods at parallel potency levels in terms of chemical shift and relative integration values. The experiment was conducted as per the limitations of the scientific method. Both methods and their controls of Natrum muriaticum were potentised to the 9C, 30C, and 200C potency levels. They were prepared in 16ml volumes and transported to the NMR spectroscopy laboratory in Pietermaritzburg for analysis. / M
89

A comparison of the 80MHz, 200MHz and 500MHz nuclear magnetic resonance spectra of homoeopathic sulphur 30CH

Cason, Angela January 2002 (has links)
Dissertation submitted in partial compliance with the requirements for the Master's Degree in Technology: Homoeopathy, Durban Institute of Technology, 2002. / The purpose of this study was to investigate whether frequency strength is a parameter requiring consideration when conducting NMR spectroscopy studies on hornoeopathic potencies. To this end, samples of Sulphur 30CH and a Lactose control were analysed using NMR spectrometers operating at three different frequency strengths of 80MHz, 200.MHz and 500.MHz. It was hypothesized that differences existed in the spectra of respective Sulphur samples, control samples, and between parallel samples of Sulphur and control. It was further hypothesized that differences between parallel samples of Sulphur and control would be more noticeable at the lower frequencies. This hypothesis was based on the assumption that a higher frequency strength would have more intense resonance effects on the structure of the homoeopathic potency, thereby disturbing the micro-structural changes induced during potentisation. The design of the investigation was that of a scientific experiment. Potencies of Sulphur and a lactose-based control were prepared to a 30CH potency each, in 87% ethanol. The final prepared volumes (10ml) of Sulphur and control were blinded by means of colour codes by a third party prior to analysis. The blinded samples were transported to the University of Natal, Pietermaritzburg, where they were subjected to analysis using the following instruments: 1) A Varian FT80A 80.MHz instrument 2) A Varian Gemini 200MHz instrument 3) A Varian Inova 500.MHz instrument At each instrument NMR spectroscopy was conducted on ten (10) samples from each group (Sulphur and control). The samples were prepared in coaxial tubes using acetone as both an external lock and reference, and NMR spectra were recorded for each sample. All the samples were run at a thermostatically controlled temperature of 24\xB0C (\xB1 O,2\xB0C), and the laboratory was maintained at a constant temperature of 22\xB0C. The spectra and data of all the samples were recorded in terms of the chemical shift and integration values of their respective CH2, H20 and OH signals. / M
90

A comparative study of the NMR spectra of parallel potencies of Sulphur with reference to similarities of concentration and dynamisationn.

Malan, Johannes Francios January 2002 (has links)
Dissertation submitted in partial compliance with the requirements for the Masters Degree in Technology: Homoeopathy, Durban Institute of Technology, 2002. / The purpose of this study was to analyse and compare the NMR spectra of homoeopathic Sulphur (the most well-known and often tested homoeopathic remedy) in two commonly used potencies, namely the centesimal (CH) and decimal (DH) potencies. Both potencies were prepared according to the Hahnemannian method. In order to assess the differences and similarities between these two potency scales, remedies with the same levels of deconcentration, and remedies with the same numbers of succussions were tested. The Control substance used was Water-Ethanol 87% without lactose or Sulphur. The Control substance was prepared in the same way as the Sulphur i.e. potentised as the Sulphur. Chemical shift and relative integration values of the H20, OH and CH2 peaks were recorded, calculated and compared. The investigation was designed as a scientific experiment. Firstly, the Sulphur remedies were compared to the Controls. Secondly, Sulphur remedies were compared to Sulphur remedies, and Controls to Controls. The following criteria were used: o Equal deconcentrations of the centesimal scale were compared to their equivalent decimal scale. o Equal numbers of succussions of the centesimal scale were compared to their equivalent decimal scale. The following potencies were assessed for both Sulphur and Control (Water-Ethanol): / M

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