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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.
1

Development of Iron-Catalyzed C-N and C-C Bond Forming Reactions toward Functional Arylamine Synthesis / 機能性芳香族アミン類の合成を志向した鉄触媒炭素-窒素及び炭素-炭素結合生成反応の開発

Aoki, Yuma 25 March 2019 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21780号 / 工博第4597号 / 新制||工||1716(附属図書館) / 京都大学大学院工学研究科物質エネルギー化学専攻 / (主査)教授 中村 正治, 教授 大江 浩一, 教授 村田 靖次郎 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM
2

The Hydrolysis of Naphthalene Diimides

Kim, Michelle B 06 August 2007 (has links)
The hydrolyses of naphthalene diimides (NDIs) bearing aliphatic side chains with N-methylpyrrolidinium groups placed two (1) and three (5) atoms from the central core were studied. The Ka values for the first and second hydrolyses for 1 were 2.5 ± 0.2 x 105 M-1 and 2.0 ± 0.1 x 102 M-1, respectively; for 5 they were 1.4 ± 0.1 x 105 M-1 and 44 ± 2 M-1, respectively. NDI 1 hydrolyzed 6.8 times faster than did 5. The rates for the first and second hydrolyses of 1 at 100 mM hydroxide measured by stopped-flow were 17.0 ± 0.2 s-1 and 53.0 ± 0.1 x 10-2 s-1, respectively. NMR showed both the syn and anti isomers of the diamide species. Syntheses of other derivatives are reported. Overall, this study shows that the rate of hydrolysis of NDIs is increased when the cationic charge is moved closer to the NDI core.
3

Baseline Susceptibility of Selected Lepidopteran Pests to Diamides and Use Strategies in Mississippi Soybean

Adams, Charles Andrew 07 May 2016 (has links)
Insecticides in the diamide class have a novel mode of action and have become a key component for management of agriculturally important lepidopteran pests since their introduction in 2008. Corn earworm, Helicoverpa zea (Boddie); and the armyworm complex including fall armyworm, Spodoptera frugiperda (J.E. Smith); and Spodoptera exigua (Hübner); are significant pests of agroecosystems in the Mid-southern and Southeastern regions of the United States. They have developed resistance to, and/or inconsistent control has occurred with most chemical classes. The objectives of this study were to establish susceptibility levels of field populations of H. zea, S. frugiperda, and S. exigua collected in the Mid-southern and Southeastern regions of the United States to flubendiamide and chlorantraniliprole. To achieve equivalent levels of mortality for each species, a higher concentration of flubendiamide was required compared to chlorantraniliprole. Furthermore, two experiments were conducted to determine the systemic and residual efficacy of chlorantraniliprole and flubendiamide against H. zea on vegetative and reproductive structures of soybean. Chlorantraniliprole moved systemically and had significantly greater control than flubendiamide in the systemic and residual study out to 31 DAT. Flubendiamide did not move systemically but provided significant residual control out to 31 DAT compared with the untreated control. Neither insecticide was detected in reproductive structures. Finally, to determine the risk of resistance development, a S. exigua colony, originating from a field collection in 2013, was separated into three cohorts that were independently selected with three concentrations (0.016, 0.020, and 0.025 ppm) of flubendiamide incorporated into a meridic diet. These concentrations were chosen from the LC30, LC60 and LC90 of the original colony. Resistance ratios never increased past 2.11old. The highest resistance ratios occurred after 18 generations for the LC30 colony, 19 generations for the LC60 colony, and 13 and 15 generations for the LC90 colony. After reaching their highest point of resistance, the colonies began to decline in egg production and larval survivability and did not recover. After 22 generations the selected colonies were terminated. The results from this portion of the study suggest that the potential for resistance development of beet armyworm to flubendiamide is unclear.
4

Synthesis and Characterization of Titanium Complexes of Aryl Diamides and Tantalum Complexes of Diphenolate Phosphine Ligands

Tsai, Ting-Ting 28 June 2012 (has links)
The novel chelating ligand, Me[NOON]H2 (N,N'-((ethane-1,2-diylbis(oxy))-bis(ethane-2,1-diyl))- bis(2,6-dimethylaniline)), have been synthesized successfully and characterized by NMR. The lithium complexes of the aryl diamide ligand have also been synthesized by n-BuLi react with neutral ligand, Me[NOON]H2. And the lithium complexes is a ether adduct according to the 1H NMR. The lithium complex, Me[NOON]Li2(OEt2) react with Ti(OiPr)4 and TiCl4(THF)2 to form the NOON titanium alkoxide and dichloride complexes respectively, and they have been characterized by 1H NMR and X-ray diffraction. These NOON titanium complexes are expected to be a catalyst for the ring opening polymerization of lactide or caprolactone in the future. The tantalum complexes of diphenolate phosphine ligands have been synthesized and characterized successfully by NMR, X-ray diffraction, and elemental analysis. The tantalum complexes, [tBuOPO]2TaX (X=Me, Et, H) is produced by the reaction of [tBuOPO]2TaCl with Grignard reagent (MeMgBr and EtMgCl) and superhydride(LiHBEt3). These tantalum complexes will be applied in dinitrogen activation in the future work.
5

Analysis of the mechanisms for uronate isomerase from E. coli, cobyrinic acid a,c-diamide synthetase from S. typhimurium, and cobyric acid synthetase from S. typhimurium.

Williams, LaKenya 15 May 2009 (has links)
Uronate isomerase catalyzes the isomerization of D-glucuronate and Dfructuronate. This enzyme has been classified as a member of the amidohydrolase superfamily. The reaction catalyzed by uronate isomerase is analogous to the isomerization of aldose/ketose sugars. These interconversions can occur via two mechanisms, a hydride or proton transfer. The solvent exchange experiments and the elimination of fluoride from 3-deoxy-3-fluoro-D-glucuronate catalyzed by the enzyme support a proton transfer. Assignment of the transferred proton as the proR proton further supports a proton transfer mechanism via a cis-enediol intermediate for uronate isomerase from E. coli. Cobyrinic acid a,c-diamide synthetase and cobyric acid synthetase from S. typhimurium catalyze ATP dependent amidations of carboxylate groups on the periphery of cobyrinic acid utilizing glutamine or ammonia as a nitrogen donor. The role of ATP in the reaction has been probed by positional isotope exchange (PIX). The results confirm the presence of phosphorylated intermediate species in the reactions catalyzed by cobyrinic acid a,c-diamide synthetase and cobyric acid synthetase from S. typhimurium. Cobyric acid synthetase catalyzes the amidation of carboxylate groups b, d, e, and g of adenosyl-cobyrinic acid a,c-diamide in the biosynthetic pathway for coenzyme B12. Analysis of the reaction time courses demonstrate the appearance of three unique intermediate species which are released from the active site after each amidation reaction. The identification of the intermediate species was accomplished by 1H, 15N HSQC NMR spectroscopy. The NMR spectrum of a sample quenched at the beginning of the reaction shows a single intermediate species corresponding to carboxamide e. Subsequent spectra establish the amidation order as e, d, b, and g. The structural basis for the dissociative and sequential reaction mechanism coupled with the rigid regiochemistry is unknown. However, mutations to aspartate 146 perturb the order of amidation. A NMR spectrum quenched early in the reaction with the D146N mutant shows two intermediate species corresponding to carboxamides e and d. Spectra of samples later in the reaction confirm the presence of multiple e, d, and g amide species. The reaction is completed with the amidation of carboxylate b.
6

The Role of Protein S-glutathionylation on Ca2+ Signaling in Cultured Aortic Endothelial Cells

Lock, Jeffrey T. 08 March 2013 (has links)
No description available.
7

Evaluation of Management Strategies for the Headworm Complex in Grain Sorghum

Dobbins, Christopher Scott 07 May 2016 (has links)
During 2013 and 2014, studies were conducted to determine the effects of Helicoverpa zea and Spodoptera frugiperda on both damage and yield of Sorghum bicolor. Results from damage ratings suggest that the amount of damage per single larva decreases as population density increases. Also, yield results suggest that one H. zea and one S. frugiperda larva per panicle results in a 3.6 and 4 percent yield loss, respectively. Additionally, a dynamic EIL was determined using crop value along with various yield potentials and control costs. Other research studies were conducted to determine the efficacy of diamide and pyrethroid insecticides on headworms when applied at midge timing for different locations and planting dates. Results suggest that diamides provide longer and better control of headworms than do pyrethroids. However, applying diamides as a preventative application at midge timing may not be economically feasible when grain prices are low.
8

Elaboration et propriétés de matériaux hybrides polymères-systèmes auto-assemblés / Elaboration and properties of hybride nanomaterials polymers-self-assembled systems

Boulaoued, Athmane 29 September 2015 (has links)
Ce travail de thèse a porté sur l’élaboration de nanomatériaux hybrides de type nano-câbles fonctionnels, composés de polymères covalents et de molécules auto-assemblées. L’approche «bottom-up» adoptée repose sur des processus uniquement physiques, à savoir la nucléation hétérogène, la cristallisation et la gélification thermo réversible. Deux systèmes hybrides ont été élaborés et étudiés: le premier est composé de molécules de tetra-2-éthylhexanoate de bicuivre (CuS8) auto-assemblées en filaments, lesquels sont encapsulés au sein des fibrilles de polystyrène isotactique (iPS). Nous avons montré au travers de différentes études (DSC, DNPA,SQUID, EXAFS et IR-TF) que leur encapsulation permet non seulement de les stabiliser mais également de modifier leur comportement antiferromagnétique. Le deuxième système a consisté à des fibrilles de poly(alkylthiophène)s (P3AT), emmaillotées au moyen de molécules diamides (BHPB-10) capables de s'assembler en nanotubes. En plus des études de la morphologie et de la structuration par TEM et UV-Vis,nous avons étudié les propriétés de conductivité du système hybride P3BT/BHPB-10 en C-AFM. Nous avons montré qu’il est effectivement possible de réaliser des nano-câbles semi-conducteur gainés. / This thesis deals with new hybrid nanomaterials of functional nanocable-like structures, consisting of covalent polymers and self-assembled molecules. The «bottom-up» approach adopted for the elaboration is based only on physical processes such as heterogeneous nucleation, crystallization and thermoreversible gelation. This original approach allowed us to easily prepare two functional nanocables: the first consisted of bicopper tetra-2-ethylhexanoate (CuS8) molecules self-assembled on filaments which are encapsulated within isotactic polystyrene (iPS) fibrils. We proved throughout different studies (DSC, SANS, SQUID, EXAFS and FT-IR) that the encapsulation allows one to get stable filaments, and particularly to modify their antiferromagnetic behavior as well. The second system constituted of poly(alkylthiophene)s fibrilles (P3AT), sheathed by diamides molecules (BHPB-10) self-assembled on nanotubes. Besides the morphological and the structuration studies (TEM and UV-Vis), we investigated the conductivity of the hybrid system P3BT/BHPB-10 by C-AFM. Results showed the possibility to obtain sheathed semi-conducting nano-cables.

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