Commercial longline fishing results in large amounts of incidental bycatch of elasmobranch fishes (sharks, skates, and rays). Teleost species lack electrosensory systems and development of technologies which target the ampullary organs of sharks provides an avenue to selectively deter elasmobranchs without affecting the catch rate of target teleosts. Electric field measurements and a controlled scientific longline study were conducted testing whether the lanthanide metal neodymium or zinc/graphite might reduce elasmobranch catch per unit effort (CPUE). Baited longline hooks were treated with neodymium and zinc/graphite and catch rates were compared to that of controls. Shark CPUE decreased by 60% on neodymium treated hooks and 80% on zinc/graphite treated hooks. The effectiveness of both treatments varied among species with significant reductions shown for Atlantic sharpnose sharks (Rhizoprionodon terranovae) but less dramatic differences for others. Zinc/graphite is potentially a viable tool for reduction of shark bycatch in a commercial longline fishery. / by Kieran Thomas Smith. / Thesis (M.S.)--Florida Atlantic University, 2013. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.

Sharks comprise a large portion of bycatch in pelagic longline fisheries worldwide. Lanthanide metals have been proposed as shark repellents. This study quantified the normalized voltage of lanthanide metals in seawater and found that there was no difference in normalized voltage among the six tested metals. Temperature and salinity had a significant effect on lanthanide normalized voltage. The output at 18ºC was significantly greater than at both 12 and 24ºC. The normalized voltage was significantly greater in freshwater than brackish or seawater. The dissolution rate for the lanthanides varied from -1.6 to -0.2g/h. As the metals dissolved the voltage remained constant. In a behavioral assay, neodymium was ineffective at repelling bonnethead sharks (Sphyrna tiburo) tested individually and in groups, and lemon sharks (Negaprion brevirostris) in groups. Due to high cost, fast dissolution rates, and lack of deterrent effects, lanthanide metals are not recommended for use in mitigating shark bycatch. / by Sara M. McCutcheon. / Thesis (M.S.)--Florida Atlantic University, 2012. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2012. Mode of access: World Wide Web.

Within solid-state chemistry, coordination polymers have gained interest for use in various applications such as sensing, catalysis, display technology, hydrogen storage, etc. The use of lanthanide ions in these materials provides a mean of exploring how structure may affect luminescence efficiency. In this study, the photophysics of several lanthanide benzenecarboxylates was studied. This data combined with data from other coordination polymers created in our lab indicate that the established guidelines for producing highly efficient materials may not correlate directly from solution to the solid state and that structure may also play a role. / by Jessica Montressa Clark. / Thesis (M.S.)--Florida Atlantic University, 2013. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.

The molecular basis of the potent transdermal enhancement activity of a series of iminosulfuranes, structure provided where X = H, Cl, Br, and I, is being investigated skin models. It has been shown (J. Lipid Res. 46(2005), 2192-2201.) that correlations exist between the activity of the aforementioned transdermal penetration enhancers (TPE) and the extent to which these agents bind to DMPC vesicles and perturb the gel to liquid crystal phase transition measured by calorimetry. The degree to which the perturbation of these compounds extends into the bilayer interior in contrast to surface activity is unclear. To gain insight into this issue, the 31P NMR resonance from DMPC and DMPC-cholesterol unilamellar vesicles have been split by the slowly penetrating paramagnetic metal ion Pr+3. The extent to which this perturbation is attenuated by transdermal penetration enhancers has been investigated as a function of Pr+3 exposure time and iminosulfurane concentration. The effect of these iminosulfuranes on bilayer integrity is also being explored by monitoring the induced release of carboxyfluorescein from DMPC and DMPC- cholesterol unilamellar vesicles.

Thesis (M.S.)--Rochester Institute of Technology, 1989. / Includes bibliographical references (leaves 62-64).

The focus of this thesis is to develop lanthanide (Ln) luminescent materials through the exploration of coordination polymers and nanomaterials. Herein, dimethyl-3,4- furanedicarboxylate acid undergoes hydrolysis under hydrothermal conditions to form coordination polymers with lanthanide ions. The resulting coordination polymers exhibited luminescent properties, with quantum yields and lifetimes for the Eu-and Tb-CP of 1.14+-0.32% and 0.387=-0.0001 mx, and 3.33=-0.82% and 0.769=-0.006 ms, respectively. While the incorporation of lanthanides was not achieved in this work, progress toward the production of pure phase InP in the nanoregime has been made, using a low-cost, hydrothermal method. Through SEM and PXRD conflict, it is believed that pure INP particles with a size range of 58-81 nm were successfully synthesized. / by Natalie E. Greig. / Thesis (M.S.)--Florida Atlantic University, 2012. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.

This thesis includes NMR studies of free base meso-tetra(otolyl) porphyrin (TTP) and meso -tetraphenylporphyrin (TPP) and their dications protonated by trifluoroacetic acid (TFA). The chemical shift changes of the -NH resonance are very unusual and have never been reported. At the beginning of the titration, the N-H resonances broaden considerably but do not shift; when the ratio of [TFA]/[TTP] or [TFA]/[TPPf are over 2, the N-H resonances shift markedly to lower field by as much as 1.6 ppm. At acid levels well above the equivalence point, the NH resonances moves back to higher field. Moreover upon protonation the NH line of TTP becomes a complex multiplet which changes as a function of [TFA]/[TTP]. The NH line of TPP remains a singlet at all acid levels. We also report here a way of isolating atropisomers of mesotetra( o -tolyl)porphyrin through HPLC by using an analytical C-18 bond pack reverse phase column eluted by a 1 %THF + 99%Me0H solvent combination. A preliminary study by HPLC was also carried out on ZnTTP(II) with aliquots of 2,6-dimethylpyridine, and the retention time of the separation decreased markedly, but this study needs to be repeated and improved. TTP and TPP dications at two different acid levels were studied by VT-NMR, and the downfield shift of -NH resonance of TTP dications was more pronounced at higher temperatures than those of TPP dications.

Abstract not available

Luminescent lanthanide containing coordination polymers and metal-organic frameworks hold great potential in many applications due to their distinctive spectroscopic properties. While the ability to design coordination polymers for specific functions is often mentioned as a major benefit bestowed upon these compounds, the lack of a meaningful understanding of the crystal engineering and luminescence in lanthanide coordination polymers remains a significant challenge toward functional design. Currently, the study of luminescence attributed to these compounds is based on the antenna effect as derived from molecular systems, where organic antennae are used to facilitate lanthanide-centered luminescence. This molecular based approach does not take into account the unique features of extended network solids, particularly the formation of band structure. By comparing molecular and band-based approaches, it was determined that the band structure of the organic sensitizing linker needs to be considered when evaluating the luminescence of lanthanide coordination polymers. This new model, as well as work on the crystal engineering and sensor applications of these materials will be presented. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2017. / FAU Electronic Theses and Dissertations Collection

The development of synthetic molecular receptors that can selectively bind anions, translocate them through a lipidic bilayer membrane and release them on the other side is a very topical and emerging field of supramolecular chemistry, warranted by the biological importance of transmembrane anion transport.The first part of this thesis is devoted to the study of the transmembrane transport of chloride and of the organic ion pair propylammonium chloride with calix[6]arene receptors functionalized with three (thio)urea arms on their small rim. The transport of chloride across the lipid bilayer of liposomes was monitored by fluorescence spectroscopy using the lucigenin assay. We report the first example of calix[6]arenes able to act as mobile carrier for the transport of chloride via a Cl-/NO3- antiport. We furthermore show that our calixarene systems are able to perform the cotransport of propylammonium chloride, with the chloride bound at the level of the (thio)urea groups and the ammonium included in the calixarene cavity. To provide direct proof of cotransport, we developed a 1H NMR methodology involving a thulium- complex shift reagent with which we were able to distinguish the signals of the ammonium transported inside the liposomes from those of the external ammonium. We also highlight the role of the complexing calixarene cavity for the cotransport by comparing the calixarenes to known transporters deprived of a cavity. The transmembrane transport organic ion pairs could find applications in the transport of biologically relevant ammonium compounds such as catecholamines and amino acids. Our results are reported in the publication “Repositioning Chloride Transmembrane Transporters: Transport of Organic Ion Pairs” Grauwels, G. Valkenier, H. Davis, A. P. Jabin, I. Bartik, K. Angew. Chemie - Int. Ed. 2019, 58, 6921–6925.The second part of this thesis is devoted to the study of binding of chloride to receptors embedded in a lipid membrane, the first step of the transmembrane transport process. Both 1H and 31P NMR spectroscopy proved to be inadequate to study the binding using liposomes or micelles as model membranes. With liposomes, the NMR signals are too broad to be exploited and in the case of micelles, the competition between the lipid headgroups and chloride made it impossible to obtain a NMR signature which unambiguously characterizes chloride binding. The 35Cl NMR signal is on the other hand strongly affected by the presence of anion receptors, both in organic solvents and when incorporated lipid bilayers. We developed a methodology to evaluate the binding of chloride, based on the monitoring of the chloride linewidth during titration experiments. A linear relationship between the linewidth and the concentration of receptors is observed and the slopes can be exploited to compare the binding strengths of different structurally related receptors. We show that 35/37Cl NMR is a versatile tool which can help in the understanding and development of new transporters by providing new insights of the physicochemical understanding of the transport process. / Doctorat en Sciences de l'ingénieur et technologie / info:eu-repo/semantics/nonPublished