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Photodegradation of propiconazole fungicide by ultraviolet radiation
Title
Photodegradation of propiconazole fungicide by ultraviolet radiation.
Creator
Martinez, Omar R., Florida Atlantic University, Parkanyi, Cyril
Abstract/Description
The photodegradation of propiconazole (1-{[2-(2,4-dichlorophenyl)-4-propyl-1,3-dioxolan-2-yl]methyl}-1 H-1,2,4-triazole), a systemic fungicide, by ultraviolet radiation has been studied. After 12 hours of continuous irradiation, propiconazole undergoes degradation in aqueous solution. The process requires the presence of oxygen and continuous agitation. Similarly, propiconazole undergoes degradation in organic solvents as well (methanol, hexane)., Four photoproducts were detected and...
Show moreThe photodegradation of propiconazole (1-{[2-(2,4-dichlorophenyl)-4-propyl-1,3-dioxolan-2-yl]methyl}-1 H-1,2,4-triazole), a systemic fungicide, by ultraviolet radiation has been studied. After 12 hours of continuous irradiation, propiconazole undergoes degradation in aqueous solution. The process requires the presence of oxygen and continuous agitation. Similarly, propiconazole undergoes degradation in organic solvents as well (methanol, hexane)., Four photoproducts were detected and identified and one of them was isolated. The dioxolan ring is the structure susceptible to the cleavage in the irradiation process.*, *Please refer to dissertation for diagram.
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Date Issued
2001
PURL
http://purl.flvc.org/fcla/dt/12841
Subject Headings
Photochemistry, Fungicides, Ultraviolet radiation
Format
Document (PDF)
Photodegradation of 2-substituted benzimidazole fungicides by ultraviolet radiation
Title
Photodegradation of 2-substituted benzimidazole fungicides by ultraviolet radiation.
Creator
Chen, Dong., Florida Atlantic University, Parkanyi, Cyril
Abstract/Description
The photodegradation of benzimidazole-based fungicides: benomyl ({1- [(butylamino) carbonyl)-1H-benzimidazol-2-yl} carbamic acid methyl ester), thiabendazole (2-(4-thiazolyl)-1H-benzimidazole) and fuberidazole (2-(2-furyl)-1H-benzimidazole) by ultraviolet radiation has been studied. Benomyl in an organic solvent (chloroform) undergoes a rapid degradation even without any UV radiation; UV radiation and air agitation will increase the rate of the reaction. The degradation product was found to...
Show moreThe photodegradation of benzimidazole-based fungicides: benomyl ({1- [(butylamino) carbonyl)-1H-benzimidazol-2-yl} carbamic acid methyl ester), thiabendazole (2-(4-thiazolyl)-1H-benzimidazole) and fuberidazole (2-(2-furyl)-1H-benzimidazole) by ultraviolet radiation has been studied. Benomyl in an organic solvent (chloroform) undergoes a rapid degradation even without any UV radiation; UV radiation and air agitation will increase the rate of the reaction. The degradation product was found to be methyl 2-benzimidazolecarbamate (MBC) in all cases. The degradation of thiabendazole and fuberidazole in methanol was also studied under different conditions but degradation was observed only under UV radiation and in the presence of oxygen, 7-8 Photodegradation products were found in the mixture after irradiation of thiabendazole but only 2 of them were separated from the mixture and identified. Benzimidazole-2-carboxamide and dimethyl oxalate were two of the final photodegradation products of thiabendazole in methanol. It is clear that the thiazole ring is the most vulnerable part of the molecule and suffers ring cleavage. No photodegradation products of fuberidazole were identified so far.
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Date Issued
1994
PURL
http://purl.flvc.org/fcla/dt/15061
Subject Headings
Benomyl, Ultraviolet radiation, Photochemistry, Fungicides
Format
Document (PDF)
Photodegradation of bromacil and terbacil by ultraviolet radiation
Title
Photodegradation of bromacil and terbacil by ultraviolet radiation.
Creator
Johnson, Hannah Kalyani, Florida Atlantic University, Parkanyi, Cyril, Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description
The photodegradation of bromacil (5-bromo-3-sec-butyl-6-methyluracil) and terbacil (5-chloro-3-tert-butyl-6-methyluracil) by ultraviolet radiation has been investigated. Irradiation of aerated aqueous solutions of the title compounds (25 ppm), led to fast degradation of both. The reactions were found to follow first order kinetics with rate constants 5.77x10^-1 hr^-1 in the case of bromacil and 8.45x10^-2 hr^-1 in the case of terbacil. Degradation in ethanol and cyclohexane was also studied,...
Show moreThe photodegradation of bromacil (5-bromo-3-sec-butyl-6-methyluracil) and terbacil (5-chloro-3-tert-butyl-6-methyluracil) by ultraviolet radiation has been investigated. Irradiation of aerated aqueous solutions of the title compounds (25 ppm), led to fast degradation of both. The reactions were found to follow first order kinetics with rate constants 5.77x10^-1 hr^-1 in the case of bromacil and 8.45x10^-2 hr^-1 in the case of terbacil. Degradation in ethanol and cyclohexane was also studied, but the solutions were not analyzed for photoproducts. The photoreaction mixture of both the herbicides in water showed four peaks on GC, indicating four photoproducts. Loss of halogens from the heterocyclic ring has been observed as shown by the presence of Br- in the case of bromacil and Cl- in the case of terbacil in the photoreaction solution. 6-Methyluracil which was isolated from the aqueous fraction of the photoreaction mixture was the common photoproduct from both bromacil and terbacil. From the organic fractions 3-sec-butyl-5-acetyl-5-hydroxyhydantoin was identified in the case of bromacil and 3-tert-butyl-5-acetyl-5-hydroxyhydantoin in the case of terbacil. The other two photoproducts were left unidentified.
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Date Issued
1993
PURL
http://purl.flvc.org/fcla/dt/14929
Subject Headings
Ultraviolet radiation, Photochemistry--Deterioration, Herbicides, Uracil
Format
Document (PDF)
Ultraviolet absorption in transparent zooplankton and its implications for depth distribution and visual predation
Title
Ultraviolet absorption in transparent zooplankton and its implications for depth distribution and visual predation.
Creator
Johnsen, Sonke, Widder, Edith A., Harbor Branch Oceanographic Institute
Date Issued
2000
PURL
http://purl.flvc.org/FCLA/DT/2783214
Subject Headings
Zooplankton, Marine animal --Physiology, Marine ecology, Ultraviolet radiation --Physiological effect
Format
Document (PDF)
Comparative study of behavioral-sensitivity thresholds to near-UV and blue-green light in deep-sea crustaceans
Title
Comparative study of behavioral-sensitivity thresholds to near-UV and blue-green light in deep-sea crustaceans.
Creator
Frank, Tamara M., Widder, Edith A., Harbor Branch Oceanographic Institute
Date Issued
1994
PURL
http://purl.flvc.org/FCLA/DT/3318881
Subject Headings
Crustacea--Behavior, Ultraviolet radiation, Decapoda (Crustacea), Shrimps, Comparative Study
Format
Document (PDF)
UV light in the deep-sea: In situ measurements of downwelling irradiance in relation to the visual threshold sensitivity of UV-sensitive crustaceans
Title
UV light in the deep-sea: In situ measurements of downwelling irradiance in relation to the visual threshold sensitivity of UV-sensitive crustaceans.
Creator
Frank, Tamara M., Widder, Edith A., Harbor Branch Oceanographic Institute
Date Issued
1996
PURL
http://purl.flvc.org/FCLA/DT/3352933
Subject Headings
Ultraviolet radiation, Crustacea, Deep-sea animals, UV light
Format
Document (PDF)
Initial investigation of the electronic structure of propylene using magnetic circular dichroism with synchrotron radiation in the vacuum ultraviolet region
Title
Initial investigation of the electronic structure of propylene using magnetic circular dichroism with synchrotron radiation in the vacuum ultraviolet region.
Creator
Boulos, Michael M., Florida Atlantic University, Snyder, Patricia Ann
Abstract/Description
This research is a preliminary investigation into the electronic transitions of Propylene. This investigation will concentrate on understanding the techniques for smoothing and calculating Gaussian fits for the experimental data. This will include knowledge of the symmetry operations for the propylene molecule and the "allowed" electronic transitions for further application to the propylene spectrum in the vacuum ultraviolet. Understanding the symmetry of the molecule and the observed...
Show moreThis research is a preliminary investigation into the electronic transitions of Propylene. This investigation will concentrate on understanding the techniques for smoothing and calculating Gaussian fits for the experimental data. This will include knowledge of the symmetry operations for the propylene molecule and the "allowed" electronic transitions for further application to the propylene spectrum in the vacuum ultraviolet. Understanding the symmetry of the molecule and the observed absorption and magnetic circular dichroism spectra is necessary for later labeling the electronic transitions.
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Date Issued
2003
PURL
http://purl.flvc.org/fcla/dt/13061
Subject Headings
Propene, Magnetic circular dichroism, Electronic structure, Far ultraviolet radiation
Format
Document (PDF)
Evidence for behavioral sensitivity to near-UV light in the deep-sea crustacean Systellaspis debilis
Title
Evidence for behavioral sensitivity to near-UV light in the deep-sea crustacean Systellaspis debilis.
Creator
Frank, Tamara M., Widder, Edith A., Harbor Branch Oceanographic Institute
Date Issued
1994
PURL
http://purl.flvc.org/FCLA/DT/3318840
Subject Headings
Crustacea, Ultraviolet radiation--Physiological effect, Crustacea--Physiology, Electrophysiology --Technique, Crustacea--Behavior
Format
Document (PDF)
INFLUENCE OF UV LIGHT ON VITAMIN D AND IMMUNE FUNCTION OF GREEN (CHELONIA MYDAS) SEA TURTLES WITH FIBROPAPILLOMATOSIS
Title
INFLUENCE OF UV LIGHT ON VITAMIN D AND IMMUNE FUNCTION OF GREEN (CHELONIA MYDAS) SEA TURTLES WITH FIBROPAPILLOMATOSIS.
Creator
Garefino, Victoria E., Milton, Sarah L., Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
Abstract/Description
Green sea turtles (Chelonia mydas) are an endangered species prone to a debilitating disease called fibropapillomatosis (FP). The aim of this study was to determine the influence of UV light on vitamin D levels and immune function in juvenile green sea turtles with FP. Phagocytosis, plasma vitamin D levels and viral load of ChHV5 were measured for FP- and FP+ turtles kept at the Gumbo Limbo Nature Center (GLNC) and for turtles caught at the St. Lucie power plant. Turtles kept at GLNC were...
Show moreGreen sea turtles (Chelonia mydas) are an endangered species prone to a debilitating disease called fibropapillomatosis (FP). The aim of this study was to determine the influence of UV light on vitamin D levels and immune function in juvenile green sea turtles with FP. Phagocytosis, plasma vitamin D levels and viral load of ChHV5 were measured for FP- and FP+ turtles kept at the Gumbo Limbo Nature Center (GLNC) and for turtles caught at the St. Lucie power plant. Turtles kept at GLNC were housed in tanks exposed to varying amounts of UV light. Turtles brought into GLNC had lower phagocytosis compared to turtles at the St. Lucie power plant. Individuals exposed to greater UV light had higher plasma vitamin D levels and a more successful recovery. The results of this project will provide rehabilitation facilities with a mechanism to improve the recovery of animals with this disease.
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Date Issued
2020
PURL
http://purl.flvc.org/fau/fd/FA00013467
Subject Headings
Chelonia mydas, Green turtle--Diseases, Fibropapillomatosis, Ultraviolet radiation, Vitamin D
Format
Document (PDF)