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- Title
- Studies on composite media as electromagnetic interference (EMI) shielding materials.
- Creator
- Iyer, Viswanathan R., Florida Atlantic University, Ungvichian, Vichate
- Abstract/Description
-
This thesis addresses pertinent studies concerning the use of electromagnetic composite media as EMI shielding materials. Specifically biphasic composites constituted by conducting and/or lossy inclusions dispersed in a dielectric host are considered. The effects of conductivity and/or dielectric loss, shape, size and volume fraction of the included component in deciding the shielding effectiveness of the composite material are ascertained over radio frequency spectrum. Theoretical studies in...
Show moreThis thesis addresses pertinent studies concerning the use of electromagnetic composite media as EMI shielding materials. Specifically biphasic composites constituted by conducting and/or lossy inclusions dispersed in a dielectric host are considered. The effects of conductivity and/or dielectric loss, shape, size and volume fraction of the included component in deciding the shielding effectiveness of the composite material are ascertained over radio frequency spectrum. Theoretical studies in modeling the effective complex permittivity of the test composite are presented in the classical and state-of-the-art perspectives and hence the shielding effectiveness of the test composite is elucidated. The theoretical considerations also refer to two types of inclusions namely, conducting particulates (metallic particles, fibers and flakes), and lossy nonmetallic inclusions. In the first case the host-inclusions system refers to polemically opposite constituents and in the later case, it is simply a dielectric-dielectric mixture. Experimental studies to evaluate the shielding effectiveness of a set of test composite are presented. Relevant descriptions include details on the test composites synthesized, experimental arrangement and the test procedure followed. Particulars on test materials constituted by a host ceramic medium (such as TiO2) with conducting inclusions such as iron particles, copper rods and aluminum flakes are presented. Measured results on the shielding effectiveness of these materials over the frequency range (200 to 1500 MHz) are listed and compared with theoretical results. Conclusions and discussions as regard to pertinent applications of such materials are presented.
Show less - Date Issued
- 1994
- PURL
- http://purl.flvc.org/fcla/dt/15013
- Subject Headings
- Electromagnetic interference, Shielding (Electricity), Radio--Interference
- Format
- Document (PDF)
- Title
- Studies on cross-talk in microstriplines.
- Creator
- Kopp, Markus Benjamin., Florida Atlantic University, Ungvichian, Vichate, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
This thesis is concerned with the analysis of the current distributions in coplanar parallel microstripline structures, and the calculation of crosstalk in these structures. This is accomplished by using a Finite Element Method approach. Two parallel strips, a right angle bend junction, and a T junction are studied in order to gain an insight into the current distributions and the primary causes of crosstalk. The control of crosstalk is also investigated, with alternative geometries for...
Show moreThis thesis is concerned with the analysis of the current distributions in coplanar parallel microstripline structures, and the calculation of crosstalk in these structures. This is accomplished by using a Finite Element Method approach. Two parallel strips, a right angle bend junction, and a T junction are studied in order to gain an insight into the current distributions and the primary causes of crosstalk. The control of crosstalk is also investigated, with alternative geometries for microstrip designs. It is seen that the finite element method can yield results comparable with other accepted methods, and other perceivable physical models of the test structures. Also shown in the present study that crosstalk can be reduced by decreasing the trace-to-ground plane separation.
Show less - Date Issued
- 1993
- PURL
- http://purl.flvc.org/fcla/dt/14954
- Subject Headings
- Microwave wiring, Crosstalk, Finite element method, Strip transmission lines
- Format
- Document (PDF)
- Title
- Studies on decapod crustacea from the Indian River region of Florida. I. Alpheus Thomasi, new species, a new snapping shrimp from the subtropical east coast of Florida (Crustacea: Decapoda: Caridea).
- Creator
- Hendrix, G. Y., Gore, R. H., Harbor Branch Oceanographic Institute
- Date Issued
- 1973
- PURL
- http://purl.flvc.org/FCLA/DT/3321191
- Subject Headings
- Decapoda (Crustacea), Snapping shrimps, Alpheus, Decapoda (Crustacea)--Florida--Identification
- Format
- Document (PDF)
- Title
- Studies on decapod crustacea from the Indian River region of Florida. II. Megalobrachium soriatum (Say, 1818): The larval development under laboratory culture (Crustacea: Decapoda; Porcellanidae).
- Creator
- Gore, R. H., Harbor Branch Oceanographic Institute
- Date Issued
- 1973
- PURL
- http://purl.flvc.org/FCLA/DT/3174417
- Subject Headings
- Decapoda (Crustacea), Porcelain crabs, Species, Larvae, Animal experimentation
- Format
- Document (PDF)
- Title
- Studies on decapod crustacea from the Indian River region of Florida. III. Callinectes bocourti A. Milne-Edwards, 1879 (Decapoda, Portunidae) from the central east coast of Florida.
- Creator
- Gore, R. H., Grizzle, Raymond E., Harbor Branch Oceanographic Institute
- Date Issued
- 1974
- PURL
- http://purl.flvc.org/FCLA/DT/3174420
- Subject Headings
- Decapoda (Crustacea), Swimming crabs, Species, Salinity, Specimens
- Format
- Document (PDF)
- Title
- Studies on decapod crustacea from the Indian River region of Florida. VI. The identity of Parthenope (Platylambrus) Serrata (H. Milne Edwards 1834) and Parthenope (Platylambrus) Granulata (Kingsley 1879).
- Creator
- Gore, R. H., Harbor Branch Oceanographic Institute
- Date Issued
- 1977
- PURL
- http://purl.flvc.org/FCLA/DT/3321195
- Subject Headings
- Decapoda (Crustacea)--Florida--Identification, Crabs--Anatomy, Crabs--Classification
- Format
- Document (PDF)
- Title
- Studies on decapod crustacea from the Indian River region of Florida. VII. A field character for rapid identification of the swimming crabs Callinectes ornatus Ordway, 1863 and C. similis Williams, 1966 (Brachyura: Portunidae).
- Creator
- Gore, R. H., Harbor Branch Oceanographic Institute
- Date Issued
- 1977
- PURL
- http://purl.flvc.org/FCLA/DT/3340736
- Subject Headings
- Decapoda (Crustacea)--Identification, Indian River (Fla. : Lagoon), Callinectes, Swimming crabs, Brachyura
- Format
- Document (PDF)
- Title
- Studies on decapod Crustacea from the Indian River region of Florida. X. A first continental record for Discias atlanticus Gurney, 1939 (Caridea, Disciadidae).
- Creator
- Gore, R. H., Wilson, Kim A., Harbor Branch Oceanographic Institute
- Date Issued
- 1977
- PURL
- http://purl.flvc.org/FCLA/DT/3336692
- Subject Headings
- Decapoda (Crustacea), Shrimps--Classification, Shrimps--Identification, Shrimps--United States
- Format
- Document (PDF)
- Title
- Studies on fouling invertebrates in the Indian River, Florida 2: effect of Modulus modulus (Prosobranchia: Modulidae).
- Creator
- Mook, David H., Harbor Branch Oceanographic Institute
- Date Issued
- 1977
- PURL
- http://purl.flvc.org/FCLA/DT/3186449
- Subject Headings
- Fouling organisms, Prosobranchia, Indian River (Fla. : Lagoon), Seagrasses--Ecology
- Format
- Document (PDF)
- Title
- Studies on fouling invertebrates in the Indian River: 1. Seasonality of settlement.
- Creator
- Mook, David H., Harbor Branch Oceanographic Institute
- Date Issued
- 1976
- PURL
- http://purl.flvc.org/FCLA/DT/3174432
- Subject Headings
- Fouling, Invertebrates, Estuaries, Hydroida, Bryozoa
- Format
- Document (PDF)
- Title
- Studies on information-theoretics based data-sequence pattern-discriminant algorithms: Applications in bioinformatic data mining.
- Creator
- Arredondo, Tomas Vidal., Florida Atlantic University, Neelakanta, Perambur S., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
This research refers to studies on information-theoretic (IT) aspects of data-sequence patterns and developing thereof discriminant algorithms that enable distinguishing the features of underlying sequence patterns having characteristic, inherent stochastical attributes. The application potentials of such algorithms include bioinformatic data mining efforts. Consistent with the scope of the study as above, considered in this research are specific details on information-theoretics and entropy...
Show moreThis research refers to studies on information-theoretic (IT) aspects of data-sequence patterns and developing thereof discriminant algorithms that enable distinguishing the features of underlying sequence patterns having characteristic, inherent stochastical attributes. The application potentials of such algorithms include bioinformatic data mining efforts. Consistent with the scope of the study as above, considered in this research are specific details on information-theoretics and entropy considerations vis-a-vis sequence patterns (having stochastical attributes) such as DNA sequences of molecular biology. Applying information-theoretic concepts (essentially in Shannon's sense), the following distinct sets of metrics are developed and applied in the algorithms developed for data-sequence pattern-discrimination applications: (i) Divergence or cross-entropy algorithms of Kullback-Leibler type and of general Czizar class; (ii) statistical distance measures; (iii) ratio-metrics; (iv) Fisher type linear-discriminant measure and (v) complexity metric based on information redundancy. These measures are judiciously adopted in ascertaining codon-noncodon delineations in DNA sequences that consist of crisp and/or fuzzy nucleotide domains across their chains. The Fisher measure is also used in codon-noncodon delineation and in motif detection. Relevant algorithms are used to test DNA sequences of human and some bacterial organisms. The relative efficacy of the metrics and the algorithms is determined and discussed. The potentials of such algorithms in supplementing the prevailing methods are indicated. Scope for future studies is identified in terms of persisting open questions.
Show less - Date Issued
- 2003
- PURL
- http://purl.flvc.org/fau/fd/FADT12057
- Subject Headings
- Data mining, Bioinformatics, Discriminant analysis, Information theory in biology
- Format
- Document (PDF)
- Title
- Studies On Means to Enhance the Effectiveness of Dienogest in the Therapy of Endometriosis.
- Creator
- Tran, Kimberly, Hartmann, James X., Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
- Abstract/Description
-
Endometriosis is an inflammatory disease that affects one in ten women, where ectopic endometrial cells grow outside of the uterus. Lesions are estrogen dependent but progesterone resistant due to decreased progesterone receptor activity. This study investigated whether a combination of dienogest, a synthetic progesterone, and calcitriol, vitamin D’s active form, had an additive or synergistic effect in the therapy of endometriosis. Experiments were conducted on immortalized endometriotic...
Show moreEndometriosis is an inflammatory disease that affects one in ten women, where ectopic endometrial cells grow outside of the uterus. Lesions are estrogen dependent but progesterone resistant due to decreased progesterone receptor activity. This study investigated whether a combination of dienogest, a synthetic progesterone, and calcitriol, vitamin D’s active form, had an additive or synergistic effect in the therapy of endometriosis. Experiments were conducted on immortalized endometriotic epithelial (12Z) and stromal (22B) cell lines. Results revealed that the combination therapy effectively inhibited cell viability in spheroids, limited proliferation, and reduced cell migration in cell monolayers of lipopolysaccharide- induced cells. Concentrations of prostaglandin E2, a key inflammatory cytokine, were measured from the supernatants of 12Z cells. The combination did not alter CD44 and progesterone receptor levels on the surface of 12Z cells. Further testing in a mouse model is necessary to determine the efficacy of the combination in vivo.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014262
- Subject Headings
- Endometriosis--Treatment, Dienogest, Calcitriol
- Format
- Document (PDF)
- Title
- Studies on modern telecommunications planning: Technoeconomical considerations and environmental issues.
- Creator
- Baeza, Daniel Michael., Florida Atlantic University, Neelakanta, Perambur S., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
The research addressed and presented in this dissertation can be placed within the broad scope of telecommunications technoeconomics. The relevant efforts include the subject-matter of identifying the issues posed by emerging technologies, related revenue considerations and environmental issues in modern telecommunications practice specific to service providers' perspectives. The topic-wise problems studied and analyzed are as follows: (1) A comprehensive portrayal of managerial concerns and...
Show moreThe research addressed and presented in this dissertation can be placed within the broad scope of telecommunications technoeconomics. The relevant efforts include the subject-matter of identifying the issues posed by emerging technologies, related revenue considerations and environmental issues in modern telecommunications practice specific to service providers' perspectives. The topic-wise problems studied and analyzed are as follows: (1) A comprehensive portrayal of managerial concerns and considerations on the technoeconomical perspectives vis-a-vis modern telecommunications; (2) Relevant analytical studies pertinent to: (1) "Greenfield starts" in a fresh, telecommunications deployment in a virgin service zone; (2) Embedded architectures; (3) Technology enhancements; (4) Environmental issues. The greenfield effort is analyzed to portray the feasibility of achieving technoeconomically optimal alternative designs. The embedded architecture refers to the prevailing infrastructure and their optimal usage is indicated via an arbitrated traffic-sharing technique. Concerning technology enhancements, "all-optical" technology is indicated as the ultimate goal. However, in the interim period, the optimal use of transitory technology such xDSL, MPLS, and others, is suggested and studied. Lastly, the environmental implications that coexist with technoeconomical impacts on modern telecommunications deployment are analyzed.
Show less - Date Issued
- 2000
- PURL
- http://purl.flvc.org/fcla/dt/12655
- Subject Headings
- Telecommunication systems--Management, Engineering economy, Telecommunication systems--Environmental aspects
- Format
- Document (PDF)
- Title
- Studies on nonlinear activity and cross-entropy considerations in neural networks.
- Creator
- Abusalah, Salahalddin Tawfiq., Florida Atlantic University, Neelakanta, Perambur S., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
The objectives of this research as deliberated in this dissertation are two-folded: (i) To study the nonlinear activity in the neural complex (real and artificial) and (ii) to analyze the learning processe(s) pertinent to an artificial neural network in the information-theoretic plane using cross-entropy error-metrics. The research efforts envisaged enclave the following specific tasks: (i) Obtaining a general solution for the Bernoulli-Riccati equation to represent a single parameter family...
Show moreThe objectives of this research as deliberated in this dissertation are two-folded: (i) To study the nonlinear activity in the neural complex (real and artificial) and (ii) to analyze the learning processe(s) pertinent to an artificial neural network in the information-theoretic plane using cross-entropy error-metrics. The research efforts envisaged enclave the following specific tasks: (i) Obtaining a general solution for the Bernoulli-Riccati equation to represent a single parameter family of S-shaped (sigmoidal) curves depicting the nonlinear activity in the neural network. (ii) Analysis of the logistic growth of output versus input values in the neural complex (real and artificial) under the consideration that the boundaries of the sets constituting the input and output entities are crisp and/or fuzzy. (iii) Construction of a set of cross-entropy error-metrics (known as Csiszar's measures) deduced in terms of the parameters pertinent to a perceptron topology and elucidation of their relative effectiveness in training the network optimally towards convergence. (iv) Presenting the methods of symmetrizing and balancing the aforesaid error-entropy measures (in the information-theoretic plane) so as to make them usable as error-metrics in the test domain. (v) Description and analysis of the dynamics of neural learning process in the information-theoretic plane for both crisp and fuzzy attributes of input values. Relevant to these topics portraying the studies on nonlinear activity and cross-entropy considerations vis-a-vis neural networks, newer and/or exploratory inferences are made, logical conclusions are enumerated and relative discussions are presented along with the scope for future research to be pursued.
Show less - Date Issued
- 1996
- PURL
- http://purl.flvc.org/fcla/dt/12447
- Subject Headings
- Neural networks (Computer science), Entropy (Information theory), Nonlinear control theory
- Format
- Document (PDF)
- Title
- Studies on performance aspects of smart wireless devices and related network services.
- Creator
- Noori, Aziz Ulhaq, Neelakanta, Perambur S., Florida Atlantic University, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
This study is a focused effort on elucidating the performance aspects of modern, handheld wireless devices and associated mobile network services. Specifically addressed thereof are: (i) Assessing the performance details on certain hardware sections of smart handheld devices and (ii) determining the performance profile of market penetration considerations vis-à-vis provisioning mobile networks. To meet the scope of this research, the projected efforts are exercised in compiling relevant...
Show moreThis study is a focused effort on elucidating the performance aspects of modern, handheld wireless devices and associated mobile network services. Specifically addressed thereof are: (i) Assessing the performance details on certain hardware sections of smart handheld devices and (ii) determining the performance profile of market penetration considerations vis-à-vis provisioning mobile networks. To meet the scope of this research, the projected efforts are exercised in compiling relevant literature and deciding the said hardware and technoeconomic performance issues. Hence, written in two parts, Part A is devoted to hardware performance details of smart, handheld devices relevant to (a) delay issues in PCB layouts; (b) crosstalk problems at the baseband level (audio/multimedia) using EMI concepts and (c) ascertaining non-catastrophic EMP/EMI effects at the RF-sections so as to implement protection strategies via compensating networks. Part B is concerned with the technoeconomics of wireless networks in supporting mobile (handheld devices). Correspondingly, two market related considerations versus service performance details are considered. The first one refers to deducing a relative performance index that includes technology (mobile speed) details plus economics profiles of the users in the service area. The second task refers to elucidating a performance index of such services in terms of hedonic pricing heuristics. The theoretical aspects of the test studies as above are supplemented with experimental and/or simulation details as appropriate. Hence, the efficacy of performance details are discussed in real-world applications. Lastly, possible research items for future studies are identified as open-questions.
Show less - Date Issued
- 2015
- PURL
- http://purl.flvc.org/fau/fd/FA00004395, http://purl.flvc.org/fau/fd/FA00004395
- Subject Headings
- Mobile communication systems -- Standards, Network performance (Telecommunications), Smartphones, Technoeconomcs, Wireless communication systems -- Technological innovations
- Format
- Document (PDF)
- Title
- STUDIES ON POLYETHYLENE GLYCOL-MEDIATED AGGREGATION AND FUSION OF AVIAN ERYTHROCYTES.
- Creator
- BATCHELOR, ROGER ALLEN., Florida Atlantic University
- Abstract/Description
-
Polyethylene glycol (PEG)-induced aggregation, hemolysis and fusion of chicken red blood ceils (CRBC's) was studied in relation to the following parameters: osmotic pressure, polymer concentration, ionic strength, electrolyte species, surface charge removal and glutaraldehyde fixation. Indirect evidence indicated that osmotic pressure does not play a primary role in aggregation and fusion of red blood cells. Maximum aggregation and fusion was obtained in solutions of 20 and 40% PEG,...
Show morePolyethylene glycol (PEG)-induced aggregation, hemolysis and fusion of chicken red blood ceils (CRBC's) was studied in relation to the following parameters: osmotic pressure, polymer concentration, ionic strength, electrolyte species, surface charge removal and glutaraldehyde fixation. Indirect evidence indicated that osmotic pressure does not play a primary role in aggregation and fusion of red blood cells. Maximum aggregation and fusion was obtained in solutions of 20 and 40% PEG, respectively. In contrast, hemolysis increased almost linearily with PEG concentration. The negative electrostatic charge due to the presence of sialic acid on the membrane surface was found to be the primary factor affecting aggregation, hemolysis and fusion. Removal of the charge by neuraminidase or screening with cations enhanced aggregation and fusion while inhibiting hemolysis. The inhibition of aggregation by glutaraldehyde fixation, and hemolysis and fusion results not attributed to surface charges, are discussed in terms of intramembrane interactions with PEG.
Show less - Date Issued
- 1977
- PURL
- http://purl.flvc.org/fcla/dt/13893
- Subject Headings
- Cell hybridization, Erythrocytes, Hemolysis and hemolysins, Membrane fusion
- Format
- Document (PDF)
- Title
- Studies on Stochastic Multi-user Scheduling in Wireless Communication.
- Creator
- Wang, Di, Morgera, Salvatore D., Wang, Xin, Florida Atlantic University, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
We developed a cross layer design which combines retransmission diversity and multi-user diversity for wireless communication. To this end, a joint design of adaptive modulation and coding with retransmission-based automatic repeat request protocol is outlined. This design is applied to devise multi-user scheduling schemes, which can optimally capture the available multi-user and retransmission diversities. In addition, the proposed on-line scheduling algorithms can operate even when the...
Show moreWe developed a cross layer design which combines retransmission diversity and multi-user diversity for wireless communication. To this end, a joint design of adaptive modulation and coding with retransmission-based automatic repeat request protocol is outlined. This design is applied to devise multi-user scheduling schemes, which can optimally capture the available multi-user and retransmission diversities. In addition, the proposed on-line scheduling algorithms can operate even when the underl ying fading channel distribution is unknown, while asymptotically converging to the offline benchmark with guarantees on prescribed fairness and rate requirements. Numerical results are provided to verify the merits of our novel schemes for multi-user transmissions over Nakagami block fading channels.
Show less - Date Issued
- 2008
- PURL
- http://purl.flvc.org/fau/fd/FA00012568
- Subject Headings
- Stochastic processes--Data processing, Wireless communication systems, Computer network protocols, Code division multiple access, Modulation (Electronics), Signal processing--Digital techniques
- Format
- Document (PDF)
- Title
- Studies on stomatopod Crustacea from the Indian River region of Florida. II. An annotated check list of the mantis shrimps of the central eastern Florida coast.
- Creator
- Gore, R. H., Becker, L. J., Harbor Branch Oceanographic Institute
- Date Issued
- 1976
- PURL
- http://purl.flvc.org/FCLA/DT/3325504
- Subject Headings
- Stomatopoda--Congresses, Shrimps--Florida, Indian River (Fla. : Lagoon)
- Format
- Document (PDF)
- Title
- Studies on stomatopod Crustacea of the Indian River region of Florida. I. Rediscovery and extension of range of Heterosquilla armata (Smith, 1881).
- Creator
- Gore, R. H., Becker, L. J., Harbor Branch Oceanographic Institute
- Date Issued
- 1975
- PURL
- http://purl.flvc.org/FCLA/DT/3321192
- Subject Headings
- Stomatopoda, Lysiosquillidae, Crustacea--Florida, Shrimps
- Format
- Document (PDF)
- Title
- Studies on the base-promoted conversion of conjugated alkynyl esters to alpha-substituted alpha-allenyl esters.
- Creator
- He, Yuanjun, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
- Abstract/Description
-
We report here the development of an efficient method for the conversion of a variety of conjugated alkynyl esters to alpha-substituted conjugated allenyl esters (racemic) through the use of strong amide bases. Substantially improved yields over typical enolate formation conditions were observed with the use of two equivalents of lithium diisopropylamide. Trapping studies indicate that the second equivalent of base likely leads to the dianion intermediate which upon addition of methyl iodide...
Show moreWe report here the development of an efficient method for the conversion of a variety of conjugated alkynyl esters to alpha-substituted conjugated allenyl esters (racemic) through the use of strong amide bases. Substantially improved yields over typical enolate formation conditions were observed with the use of two equivalents of lithium diisopropylamide. Trapping studies indicate that the second equivalent of base likely leads to the dianion intermediate which upon addition of methyl iodide and trimethylsilyl chloride gives mixtures of alpha-substituted conjugated allenyl and beta,gamma-alkynyl deconjugated esters. Further optimization revealed that additive salts such as LiCl lead primarily to the allenyl product while the use of HMPA as a cosolvent gives the beta,gamma-alkynyl deconjugated alkylation product. The role of base, base concentration and electrophile on product yield and selectivity is also discussed. The optimized conditions resulting from our study of this reaction establishes this method as a viable synthetic tool for the production of alpha-substituted allenyl esters. A new method to prepare racemic alpha-tributylstannyl-alpha-allenyl esters from precursor conjugated alkynyl esters in good yields is reported. Key features of the optimized reaction conditions include the use of multiple equiv. of lithium diisopropylamide in THF with LiCl as a key additive. The allenyl tin reagent reacts with aldehydes in the presence of Lewis acid to give homopropargyl alcohol or allenyl alcohol products depending on the reaction conditions. The addition of boron trifluoride etherate to a solution of the allenyltin and aldehyde gives the homopropargyl alcohol. However, allenyl alcohol products are obtained exclusively with the addition of tin tetrachloride to the allenyl stannane rapidly followed by the addition of aldehyde. The effect of other Lewis acids and reaction variables such as solvent and temperature on the yield and relative stereochemistry of the products will also be described. The Mitsunobu coupling reaction of sterically hindered phenols and alcohols is greatly accelerated by the use of high reaction concentration in combination with sonication. The rate acceleration effect observed with our protocol may simply be based on the high concentration with the sonic waves providing efficient mixing of the highly viscous reaction mixture and generating localized hot spots, or in part, the result of an enhancement of a radical reaction pathway.
Show less - Date Issued
- 2005
- PURL
- http://purl.flvc.org/fcla/dt/12120
- Subject Headings
- Chemistry, Organic
- Format
- Document (PDF)