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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.

Energy transfer in lanthanide complexes

Clarkson, Ian Michael January 1999 (has links)
This thesis details investigations into the photophysical properties of lanthanide ions in a number of different systems. The preparation and characterisation of lanthanide containing surfactant salts of the type Ln(A0T)(_3) (Ln = Tb, Nd, Eu, AOT = bis-(2-ethylhexyl) sulfosuccinate) is described. Small angle neutron scattering experiments have been used to determine the size and shape of reverse micelles formed by these surfactants in water/cyclohexane microemulsions. The luminescence lifetimes of the lanthanide ions have been used to investigate the solvation environment within reverse micelle systems as a function of water content. The use of lanthanide complexes based on 1,4,7,10-tetraazacyclododecane bearing phenanthridine antenna in luminescence microscopy has been explored. Samples such as silica particles, onion skin cells and guinea pig heart cells have been imaged. Time- resolved measurements have allowed time gating of the sample from a fluorescent background and lifetime maps of the images have been obtained. The preparation and characterisation of deuteriated complexes of dota (1,4,7,10- tetraazacyclododecane-1,4,7,10-tetraacetic acid) with lanthanide ions is described. Selective deuteriation of both the ring and arm sites allow the relative quenching effects of C-H/D oscillators to be determined for various lanthanides in a series of structurally well defined complexes. Finally, investigations into the distance dependence of the energy transfer between aromatic chromophores and lanthanide ions have been undertaken. The synthesis of a model system linking a phenanthridine donor to a europium complex by poly(valine) spacer units is described. Preliminary photophysical results show that the quantum yield of emission by europium decreases as the distance between the donor acceptor pair is increased.

Interaction et structure de copolymères neutres-chargés dissymétriques en solution aqueuse /

Muller, François January 2000 (has links)
Thèse de doctorat : Physique des liquides : La Rochelle : 2000. / Notes bibliogr.

Rhéoépaississement de systèmes auto-associatifs de la famille CnTAB

Dehmoune, Jalal Decruppe, Jean-Paul January 2007 (has links) (PDF)
Thèse de doctorat : Physique : Physique de la matière : Metz : 2007. / Thèse soutenue sur ensemble de travaux. Bibliogr. p. 155-161. Liste des fig. p. 162-167. Liste de tabl. p. 168-169.

Cinétiques photo-induites à l'échelle nanoseconde de composés à transition d'état de spin et propriétés optiques de nanoparticules à transition d'état de spin

Fouché, Olivier Freysz, Éric. Degert, Jérôme. January 2009 (has links) (PDF)
Thèse de doctorat : Sciences physiques et de l'ingénieur. Lasers, matières, nanosciences : Bordeaux 1 : 2009. / Titre provenant de l'écran-titre.

Deposition of cationic polymer micelles on planar and patterned SiO₂ surfaces

Hahn, Jungseok. Webber, Stephen E., January 2003 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2003. / Supervisor: Stephen E. Webber. Vita. Includes bibliographical references. Available also from UMI Company.

Deposition of cationic polymer micelles on planar and patterned SiO₂ surfaces

Hahn, Jungseok 07 July 2011 (has links)
Not available / text

Changing the Structure of Casein Micelles to Improve the Delivery of Bioactive Compounds

Rahimi Yazdi, Saeed 22 May 2012 (has links)
This thesis is an investigation of binding of casein micelles to polyphenols such as epigallocatechin gallate (EGCG), resveratrol, and curcumin. The incorporation of the bioactive molecules in casein micelles seems to be beneficial. The results from this study clearly demonstrated that casein micelles can incorporate polyphenols. There is a difference in the binding behaviour between curcumin and resveratrol. Curcumin is able to penetrate the core of the micelles, but resveratrol has less affinity for the hydrophobic sites, instead, it can be bind in the core of the micelles through the water channels. The processing of milk (heating, cooling, static high pressure and microfluidization) alters the surface or the internal structure of the casein micelles resulting in increased incorporation. The release of β-casein caused alteration to the core of the casein micelles, without any effect on the colloidal calcium phosphate composition and any changes in the surface properties of the micelles. These internal rearrangements lead to an increase in the affinity of the hydrophobic sites for curcumin and resveratrol in the inner core of the micelles. This work clearly confirmed that β -casein plays a role in stabilizing internal structures in the casein micelle and its release causes an increase in the micellar size by increasing the hydration and repulsion occurring within the water pockets present in the inhomogeneous inner structure of the casein micelles. Inner core of casein micelles undergoes rearrangements during application of static high pressure and microfluidization. In the case of static high pressure, the results indicated that the persistent rearrangement of the amino acid residues induced by high-pressure treatment result in an increase in the amount of curcumin association with milk proteins. It was shown that in both untreated and microfluidized milk, the presence of polyphenol molecules significantly affects rennet induced gelation, by delaying the gelation. However, the behavior of casein micelles incorporated with resveratrol is different comparing to curcumin, as resveratrol strongly affected the surface interactions during rennet-induced gelation. Further research is needed to explain the practical aspect ( functionalities such as acid gelation, emulsification and foaming) of application of casein micelles as natural nanocarrier of bioactive compounds. / The National Sciences and Engineering Research Council (NSERC),The Ontario Dairy Council.

The characterization of cationic pseudostationary phases for electrokinetic chromatography

Schnee, Vincent Patrick. January 2007 (has links)
Thesis (Ph. D.)--University of Montana, 2007. / Title from title screen. Description based on contents viewed Aug. 13, 2008. Includes bibliographical references (p. 102-108).

Efficiency enhancements in micellar liquid chromatography through selection of stationary phase and mobile phase organic modifier /

Thomas, David Paul. Foley, Joe Preston, January 2009 (has links)
Thesis (Ph.D.)--Drexel University, 2009. / Includes abstract and vita. Includes bibliographical references (leaves 186).

Evaporation-induced 3-dimensional diblock copolymer micelles micropattern : applications as templated polymeric microwells for cell culture scaffold, bioanalytic arrays and micro-silver networks /

Chan, Yannie Ka Yan. January 2004 (has links)
Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2004. / Includes bibliographical references (leaves 122-133). Also available in electronic version. Access restricted to campus users.

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