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Elemental composition of the coral Pocillopora damicornis exposed to elevated seawater ammonium
Title
Elemental composition of the coral Pocillopora damicornis exposed to elevated seawater ammonium.
Creator
Muller-Parker, Gisèle, Cook, Clayton B., D'Elia, C. F.
Date Issued
1994
PURL
http://purl.flvc.org/fau/fd/FA00007225
Subject Headings
Corals, Zooxanthellales, Ammonium, Seawater, Nitrogen, Phosphorus, Carbon
Format
Document (PDF)
The response of interstitial ammonium in eelgrass (Zostera marina L.) beds to environmental perturbations
Title
The response of interstitial ammonium in eelgrass (Zostera marina L.) beds to environmental perturbations.
Creator
Short, F. T., Harbor Branch Oceanographic Institute
Date Issued
1983
PURL
http://purl.flvc.org/FCLA/DT/3331842
Subject Headings
Eelgrass, Zostera marina, Ammonium, Nitrogen, Environmental perturbations
Format
Document (PDF)
Synthesis and Bioactivity Investigation of Bridged Bicyclic Compounds and a Mechanistic Investigation of a Propargyl Hydrazine Cycloaddition Catalyzed by an Ammonium Salt
Title
Synthesis and Bioactivity Investigation of Bridged Bicyclic Compounds and a Mechanistic Investigation of a Propargyl Hydrazine Cycloaddition Catalyzed by an Ammonium Salt.
Creator
St.Germain, Elijah, Lepore, Salvatore D., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description
We report the development of a general route to the synthesis of [4.3.1], [3.3.1], an especially [3.2.1] bicyclic compounds structurally related to vitisinol D, a natural product. This allows for diastereoselective synthesis of bicyclic compounds with five adjacent chiral centers. This route was employed in a preliminary SAR investigation into the neuroprotectant effect of small molecules in an in vivo experiment measuring the degree of restorative effect of synaptic transmission in the...
Show moreWe report the development of a general route to the synthesis of [4.3.1], [3.3.1], an especially [3.2.1] bicyclic compounds structurally related to vitisinol D, a natural product. This allows for diastereoselective synthesis of bicyclic compounds with five adjacent chiral centers. This route was employed in a preliminary SAR investigation into the neuroprotectant effect of small molecules in an in vivo experiment measuring the degree of restorative effect of synaptic transmission in the neuromuscular junction of Drosophila melanogaster larvae under acute oxidative stress. One of the compounds exhibited intriguing potential as a neuroprotectant and outperformed resveratrol in restoring synaptic function under oxidative stress. The hypothesis that bridged bicyclic compounds may hold promise as drug scaffolds due to their conformational rigidity and ability to orient functional appendages in unique orientations is developed. The second focus is a mechanistic investigation into a tetrabutylammoniumcatalyzed cycloaddition as evidence of a novel ammonium-alkyne interaction. A carbamate nitrogen adds to a non-conjugated carbon–carbon triple bond under the action of an ammonium catalyst leading to a cyclic product. Studies in homogeneous systems suggest that the ammonium agent facilitates cyclitive nitrogen–carbon bond formation through a cation–π interaction with the alkyne unit. Using Raman spectroscopy, this cation–π interaction is directly observed for the first time. DFT modeling elucidated the mechanistic factors in this cycloaddition. A teaching experiment was developed based on this mechanistic investigation. Control experiments were employed to demonstrate the testing of two alternative mechanistic hypotheses. Cyclization reactions were performed with a soluble base (sodium phenoxide) with and without tetrabutylammonium bromide under homogeneous conditions. Students observed that ammonium salt accelerates the reaction. They were encouraged to develop a testable hypothesis for the role of the ammonium salt in the cyclization mechanism: typical phase transfer or other. IR spectroscopy was used to directly observe a dose dependent shift of the alkyne stretching mode due to a cation−π interaction. Undergraduates were able to employ the scientific method on a contemporary system and see how data are generated and interpreted to adjudicate between rival hypotheses in a way that emulates authentic and current research in a lab setting.
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Date Issued
2018
PURL
http://purl.flvc.org/fau/fd/FA00013100
Subject Headings
Bicyclic compounds., Ammonium salts., Cycloaddition Reaction.
Format
Document (PDF)
Effects of ammonium nitrate on sensitivity for determinations of copper, iron, and manganese in sea water by atomic absorption spectrometry with pyrolytically coated graphite tubes
Title
Effects of ammonium nitrate on sensitivity for determinations of copper, iron, and manganese in sea water by atomic absorption spectrometry with pyrolytically coated graphite tubes.
Creator
Montgomery, John R., Peterson, Gary N., Harbor Branch Oceanographic Institute
Date Issued
1980
PURL
http://purl.flvc.org/FCLA/DT/3331817
Subject Headings
Ammonium nitrate, Seawater--Analysis, Atomic absorption spectroscopy
Format
Document (PDF)
The seagrass, Zostera Marina L.: plant morphology and bed structure in relation to sediment ammonium in Izembek Lagoon, Alaska
Title
The seagrass, Zostera Marina L.: plant morphology and bed structure in relation to sediment ammonium in Izembek Lagoon, Alaska.
Creator
Short, F. T., Harbor Branch Oceanographic Institute
Date Issued
1983
PURL
http://purl.flvc.org/FCLA/DT/3331843
Subject Headings
Zostera marina, Eelgrass, Izembek Lagoon (Alaska), Ammonium, Plant morphology
Format
Document (PDF)
Nutrient couplings between on-site sewage disposal systems, groundwaters, and nearshore surface waters of the Florida Keys
Title
Nutrient couplings between on-site sewage disposal systems, groundwaters, and nearshore surface waters of the Florida Keys.
Creator
Lapointe, Brian E., O'Connell, Julie D., Garrett, G. S.
Date Issued
1990
PURL
http://purl.flvc.org/FCLA/DT/3333152
Subject Headings
Groundwater, Sewage disposal, Ammonium, Florida Keys (Fla.), Nutrient pollution of water, Eutrophication
Format
Document (PDF)
Effects of a decomposing drift algal mat on sediment pore water nutrient concentrations in a Florida seagrass bed
Title
Effects of a decomposing drift algal mat on sediment pore water nutrient concentrations in a Florida seagrass bed.
Creator
Zimmermann, Carl F., Montgomery, John R., Harbor Branch Oceanographic Institute
Date Issued
1984
PURL
http://purl.flvc.org/FCLA/DT/3350848
Subject Headings
Seagrasses, Pore water --Florida --Indian River, Algae --Ecology, Sediment control, Ammonium, Phosphate deposits
Format
Document (PDF)
Production and nutrient dynamics of a Syringodium filiforme Kütz. seagrass bed in Indian River Lagoon, Florida
Title
Production and nutrient dynamics of a Syringodium filiforme Kütz. seagrass bed in Indian River Lagoon, Florida.
Creator
Short, F. T., Montgomery, John R., Zimmermann, Carl F., Short, C. A., Harbor Branch Oceanographic Institute
Date Issued
1993
PURL
http://purl.flvc.org/FCLA/DT/3174032
Subject Headings
Seagrasses, Plant nutrients, Aquatic ecology, Sediment transport, Ammonium --Environmental aspects --Measurement
Format
Document (PDF)