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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.
111

Establishment Of Blackberries And Detection And Management Of Raspberry Crown Borer

Heard, Edward 09 December 2006 (has links)
Evaluations of tactics for detection and management of raspberry crown borer, RCB, Pennisettia marginata (Harris) on blackberries were performed in Mississippi from January 2005 - July 2006. Randomized split plots with infested blackberries and certified nursery stock of two recommended cultivars, thorny ?Chickasaw? and thornless ?Apache? were planted. Pest management tactics targeting RCB included drenches: chemical insecticide bifenthrin, recently registered for RCB management; experimental pesticide E2Y45; and entomopathogenic nematodes Steinernema feltiae. Insect pheromones (E,Z)3-13-octadecadien-1-ol and (E,Z)3-13-octadecadien-1-yl-acetate were evaluated as RCB lures. Effects of fungicides captan, pyraclostrobin + boscalid, lime-sulfur and insecticide acetamiprid on viability and infectivity of entomopathogenic nematode species, S. feltiae and Heterorhabditis bacteriophora were evaluated in laboratory bioassays with host greater wax moth larvae. RCB larvae and soil pests on and around infested blackberry plants were observed. Bait traps with 5 mg of (E.Z)3-13-octadecadien-1-ol captured an adult RCB on October 19, 2005. Laboratory bioassays indicated that lime-sulfur and pyraclostrobin + boscalid decrease nematode movement and infectivity.
112

Liquid crystal polymers containing crown ether ligands

Rodenhouse, Randall Alan January 1991 (has links)
No description available.
113

Synthesis and Characterization of Amphiphilic Polymers

Collette, Elisabeth Anne January 2013 (has links)
No description available.
114

Creation of a ternary complex between a crown ether, 4-aminobenzoic acid and 3,5-dinitrobenzoic acid

Boardman, N.D., Munshi, Tasnim, Scowen, Ian J., Seaton, Colin C. 02 1900 (has links)
Yes / The creation of ternary multi-component crystals through the introduction of 18-crown-6 to direct the hydrogen-bonding motifs of the other molecular components was investigated for 3,5-dinitrobenzoic acid (3,5-dnba) with 4-aminobenzoic acid (4-aba). The creation of a binary complex between 18-crown-6 and 4-aba (C12H24O6·2C7H7NO2)2 and a ternary salt between 3,5-dnba, 18-crown-6 and 4-aba (C12H24O6·C7H8NO2+·C7H3N2O6−·C7H4N2O6) were confirmed by single-crystal structure determination. In both structures, the amino molecules bind to the crown ether through N—H...O hydrogen bonds, leaving available only a single O atom site on the crown with restricted geometry to potentially accept a hydrogen bond from 3,5-dnba. While 3,5-dnba and 4-aba form a binary co-crystal containing neutral molecules, the shape-selective nature of 18-crown-6 preferentially binds protonated amino molecules, thereby leading to the formation of the ternary salt, despite the predicted low concentration of the protonated species in the crystallizing solution. Thus, through the choice of crown ether it may be possible to control both location and nature of the available bonding sites for the designed creation of ternary crystals.
115

The crown lands and the parliamentary acts of resumption, 1399-1495

Wolffe, Bertram Percy January 1954 (has links)
No description available.
116

Performing the law : the theatrical features of Demosthenes’ On the crown

Serafim, Andreas 21 September 2010 (has links)
Scholarly analysis of rhetorical speeches over the last century has been concentrated on the “traditional” ways of approaching this kind of texts, without paying much attention to their theatrical nature. The old critical analysis paid attention primarily (if not exclusively) to textual issues such as the recognition of grammatical points and the use of such texts as sources of information about historical and legal issues. The interest of scholars focuses, recently, on the study of rhetorical speeches as performances. Although some critical approaches of Demosthenes’ On the Crown appeared over the last few years, there is no systematic argument about the theatrical features of this masterpiece. By reading On the Crown, I emphasize the connection between law and theater and I suggest that rhetoric has its own “performativity”. The speech is a judicial performance: the speaker is like an actor, the court rostrum is like a theatrical scene and the audience that will vote for Demosthenes consists of the same people who take part in a theatrical performance, praising or booing the actors. The comic and tragic language and imagery, the use of emotional appeals (pathos) that is associated with the construction of characters (ēthopoiia), and finally, delivery (hypocrisis) are important theatrical devices, which Demosthenes uses in the speech. This report has a twofold structure: first, it offers a brief theoretical survey of the above-mentioned theatrical devices. Second, it provides a text-based analysis of the theatrical features of On the Crown, discussing how Demosthenes by using theatrical techniques in his speech succeeds in persuading the audience of the Crown trial and gaining an overwhelming victory over Aeschines. / text
117

Synthesis of Crown Ether/Ammonium Salt for Electron Transfer Study

Han, Dong 05 1900 (has links)
The theoretical model of Beratan and Onuchic predicts a large attenuation of ET rates through hydrogen bonds; however, the effect of individual hydrogen bond on electron transfer reaction has not been systematically studied. The organic complexes in this study are a series of crown ether/ammonium salt, which incorporate a redox partner on each component of the complex. The dimethoxynaphthalene redox donor was attached to the crown ether and a series of ammonium salts was synthesized which bear substituted quinone and naphthoquinone acceptor. The complexes characterization and preliminary electron transfer rate measurement were completed with UV/Vis and steady-state emission spectroscopy.
118

Design and Synthesis of Novel Cage-Functionalized Crown Ethers: A New Class of Ag Complexants.

Lai, Huiguo 08 1900 (has links)
Three different types of cage crown ethers have been prepared and their complexation properties with Ag(I) have been studied. Atomic absorption, fluorescence quenching, and UV absorption have been used to study the interaction between the hosts (cage crown ethers) and guests (Ag+). For the cage-annulated crown ethers that contain aromatic rings, cation-π and π-π interactions may contribute significantly to the overall complexation ability of the host system. Piperazine groups may cooperate, and the piperazine nitrogen atoms provide unshared electrons, which may form a complex with Ag+. In addition, relatively soft donor atoms (e.g., Br) are well-suited for complexation with Ag+, which is a softer Lewis acid than alkali metal cations.
119

Synthesis and properties of novel cage-functionalized crown ethers and cryptands.

Hazlewood, Anna 08 1900 (has links)
A novel cryptand was synthesized which contained a 3,5-disubstituted-4- oxahexacyclo[5.4.1.02,6.03,10.05,9.08,11] dodecane "cage" moiety. In alkali metal picrate extraction experiments the cryptand exhibited high avidity towards Rb+ and Cs+, when compared with the corresponding model compound. A computational study of a series of cage-functionalized cryptands and their alkali metal-complexes was performed. The X-ray crystal structure of a K+-complexed bis-cage-annulated 20-crown-6 was obtained. The associated picrate anion was found to be intimately involved in stabilization of the host-guest complex. The interaction energy between the host-guest complex and picrate anion has been calculated, and the energy thereby obtained has been corrected for basis set superposition error.
120

Synthesis and host-guest interaction of cage-annulated podands, crown ethers, cryptands, cavitands and non-cage-annulated cryptands.

Chen, Zhibing 05 1900 (has links)
Symmetrical cage-annulated podands were synthesized via highly efficient synthetic strategies. Mechanisms to account for the key reaction steps in the syntheses are proposed; the proposed mechanisms receive support from the intermediates that have been isolated and characterized. An unusual complexation-promoted elimination reaction was studied, and a mechanism is proposed to account for the course of this reaction. This unusual elimination may generalized to other rigid systems and thus may extend our understanding of the role played by the host molecules in "cation-capture, anion-activation" via complexation with guest molecules. Thus, host-guest interaction serves not only to activate the anion but also may activate the leaving groups that participate in the complexation. Complexation-promoted elimination provides a convenient method to desymmetrize the cage while avoiding protection/deprotection steps. In addition, it offers a convenient method to prepare a chiral cage spacer by introducing 10 chiral centers into the host system in a single synthetic step. Cage-annulated monocyclic hosts that contain a cage-butylenoxy spacer were synthesized. Comparison of their metal ion complexation behavior as revealed by the results of electrospray ionization mass spectrometry (ESI-MS), alkali metal picrate extraction, and pseudohydroxide extraction with those displayed by the corresponding hosts that contain cage-ethylenoxy or cage-propylenoxy spacers reveals the effect of the length of the cage spacer upon the host-guest behavior. A series of cage-annulated cryptands, cavitands and the corresponding non-cage-annulated model compounds have been synthesized. These host molecules display unusual behavior when examined by using ESI-MS techniques, i.e., they bind selectively to smaller alkali metal ions (i.e., Li+ and Na+), a result that deviates significantly from expectations based solely upon consideration of the size-fit principle. It seems likely that this behavior results from the effect of the host topology on host-guest behavior. A series of non-cage-annulated cryptands also have been synthesized. These compounds can serve as starting materials for cavitand construction.

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