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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.
11

The photochemistry of polyhalomethanes in water and the water-catalyzed dehalogenation reactions of selected isopolyhalomethanes, halogenated methanols and halogenated formaldehydes

Guan, Xiangguo. January 2006 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2007. / Title proper from title frame. Also available in printed format.
12

Halogenolyses of tri-alkylborane /

Lu, Qingyi. January 1990 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 1990. / Typescript. References: leaves 66-70.
13

Proteomic study of Burkholderia sp. MBA4 in the degradation of haloacids

Kwok, Sui-yi., 郭瑞儀. January 2007 (has links)
published_or_final_version / abstract / Biological Sciences / Doctoral / Doctor of Philosophy
14

Investigation and application of aryl carbon-halogen bond cleavage with rhodium and iridium porphyrin complexes.

January 2014 (has links)
本論文主要研究銥和銠卟啉絡合物與鹵代苯 (ArX, X = Cl, Br, I)的碳-鹵鍵(Ar-X)的斷裂反應及其應用。本論文分為四個部分:(1)銠卟啉絡合物與鹵代苯(ArX, X = Cl, Br, I)之間的碳-鹵鍵(Ar-X)斷裂反應;(2)氟氯化苯的碳-氟鍵(Ar-F)與碳-氯鍵(Ar-Cl)斷裂的競爭反應;(3)氟取代基對金屬(銥和銠)-芳香碳(M-Ar)鍵強弱的影響;以及(4)銥卟啉氟硼荧絡合物的合成。 / 第一部分闡述了銠卟啉絡合物(Rh(ttp)Cl)與鹵代苯(ArX, X = Cl, Br, I) 之間的碳-鹵鍵 (Ar-X) 斷裂反應以及反應機理。在鹼性條件下,無論富電子還是缺電子的鹵代苯都能與Rh(ttp)Cl反應,生成Ar-X鍵斷裂的產物──銠卟啉芳基絡合物(Rh(ttp)Ar) 。機理研究顯示, Rh(ttp)Cl 首先與氫氧根離子反應生成Rh(ttp)OH,進而通過二聚反應生成[Rh(ttp)]₂。[Rh(ttp)]₂在加熱條件下與Rh(ttp)自由基可以互相轉化,產生的Rh(ttp)自由基與鹵代苯進行原位取代反應,生成銠卟啉芳基絡合物(Rh(ttp)Ar)和鹵素自由基。鹵素自由基可以和另一個Rh(ttp)自由基反應生成Rh(ttp)X,在氫氧根離子存在的條件下,Rh(ttp)X將再次轉化為Rh(ttp)OH繼續反應。 / 第二部分描述了氟氯化苯中碳-氟鍵(Ar-F)與碳-氯鍵(Ar-Cl)斷裂的競爭反應。機理研究顯示碳-氟鍵(Ar-F)斷裂的中間體是M(por)⁻,而碳-氯鍵(Ar-Cl)斷裂的中間體是MII(por)。因此,我們可以通過改變反應條件而控制生成物。例如,在較低溫度下和強鹼性的極性溶劑中,以M(por)⁻前體作為反應物,可以獲得較多的碳-氟鍵(Ar-F)斷裂的產物;而在較高溫度下和弱鹼性的非極性溶劑中,可以獲得較多的碳-氯鍵(Ar-Cl)斷裂的產物。 / 第三部分敘述了間位氟取代基對金屬-芳香碳(M-Ar)鍵的增強作用。有間位氟取代基的金屬(銥,銠)卟啉芳基絡合物(M(ttp)ArF)是最穩定的同分異構體。在250°C條件下,當反應30天後,Ir(ttp)C₆H₄F的三個異構體達到平衡狀態,其鄰位:間位:對位的比例大約為0:5:1。理論計算的結果也顯示Ir(ttp)(3-fluorophenyl)相對Ir(ttp)(2-fluorophenyl)和Ir(ttp)(4-fluorophenyl)有更低的能量。氟取代基在鄰位時,氟與卟啉之間空間位阻較大,減弱了金屬-芳香碳(M-Ar)鍵的鍵能。與氟取代基在對位相比,在間位時具有更好的吸電子效應,從而增加了金屬-芳香碳(M-Ar)鍵的極性,增強了金屬-芳香碳(M-Ar)鍵鍵能。 / 第四部分描述了利用碳-鹵鍵 (Ar-X) 的斷裂,合成銥卟啉氟硼荧絡合物的反應。銥卟啉氟硼荧絡合物的產率可以達到70%。銥卟啉氟硼荧絡合物在生物成像和放射療法都有潛在的應用。銥卟啉氟硼荧絡合物是用金屬自由基與氟硼荧反應合成的。 / This thesis focuses on the reaction scopes, mechanistic investigations and applications of base-promoted aryl carbon-halogen (Ar-X) bond cleavage with iridium and rhodium porphyrin complexes. This thesis is divided into four parts: (1) Ar-X (X = Cl, Br, I) bond cleavage with Rh(ttp)Cl; (2) competitive Ar-F and Ar-Cl bond cleavage with iridium and rhodium porphyrins; (3) fluorine substituent effect on the M-Ar (M = Ir, Rh) bond strength; and (4) synthesis of iridium porphyrin BODIPY complexes. / Part I describes the reaction scopes and mechanism of Ar-X (X = I, Br, Cl) bond cleavage with Rh(ttp)Cl (ttp = 5,10,15,20-tetratolylporphyrinato dianion). Under basic conditions, both electron-rich and electron-deficient ArX undergo Ar-X bond cleavage to give Rh(ttp)Ar in good yields. [with diagram] / The mechanistic investigations suggest that RhIII(ttp)Cl first undergoes ligand substitution by OH- to give RhIII(ttp)OH, which forms [RhII(ttp)]₂ through reductive dimerization. RhII(ttp) radical, which is in equilibrium with [RhII(ttp)]₂, cleaves the Ar-X (X = I, Br, Cl) bond through metalloradical ipso-substitution and gives RhIII(ttp)Ar and X radical. X radical recombines with another RhII(ttp) radical to generate RhIII(ttp)X, which gives back RhIII(ttp)OH through ligand substitution by OH-. [with diagram] / Part II describes the competitive Ar-F and Ar-X (X = Cl, Br) bond cleavage reactions of fluorochlorobenzenes with iridium and rhodium porphyrin complexes. Mechanistic studies suggest that M(por)⁻ is the intermediate for the Ar-F bond cleavage while MII(por) is the intermediate for the Ar-X bond cleavage. By taking advantage of the difference in mechanisms of the Ar-F and Ar-X bond cleavages, the selectivity of bond cleavage can be controlled by varying the reaction conditions. The Ar-F bond cleavage is favored in a polar solvent with a stronger base at lower temperatures with M(por)⁻ precursor, and the Ar-X bond cleavage is favored under non-polar conditions with a weaker base and at higher temperatures. [with diagram] / Part III describes the meta-fluorine substituent effect on strengthening the M-Ar (M = Ir, Rh) bond of M(ttp)ArF. M(ttp)ArF with meta-fluorine substituent are the most stable isomers among the isomeric Ar-H bond cleavage products. At 250 °C for 30 days, the three isomers of Ir(ttp)C₆H₄F reached an equilibrium with o : m : p = 0 : 5 : 1. The theoretical calculations also suggest that Ir(ttp)(3-fluorophenyl) is of lower energy than Ir(ttp)(2-fluorophenyl) and Ir(ttp)(4-fluorophenyl). The ortho-fluorine substituent exhibits steric effect which weakens the M-Ar bond. The meta-fluorine, which is more electron-withdrawing than para-fluorine, enhances the polarity of the M-C(ipso) bond and thus strengthens the M-Ar bond. [with diagram] / Part IV describes the application of Ar-I bond cleavage with Ir(ttp)(CO)Cl in synthesizing iridium porphyrin boron-dipyrromethene (BODIPY) complexes, which are potential photosensitizers for biological imaging and photodynamic therapy. The clinically interested iridium porphyrin BODIPY complexes have been prepared by a radical process of metalloradical with BODIPY. [with diagram] / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Qian, Yingying. / Thesis (Ph.D.) Chinese University of Hong Kong, 2014. / Includes bibliographical references. / Abstracts also in Chinese.
15

AEROSOL SENSITIZATION OF GUINEA PIGS WITH HALOGENATED DINITROPHENYL COMPOUNDS

Luscri, Bruno Joseph, 1928- January 1966 (has links)
No description available.
16

A study of the alternative oxidase (AOX) pathway in wild-type Arabidopsis thaliana and the production of an inducidble (aox 1) antisense plant / by Felicity Johnson Potter.

Potter, Felicity Johnson January 1998 (has links)
Bibliography: leaves 175-186. / 186 leaves : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Aims to examine the AP in A. thaliana and to produce an inducible antisense plant to assist future studies of the role of AOX. / Thesis (Ph.D.)--University of Adelaide, Dept. of Botany, 1999?
17

Proteomic study of Burkholderia sp. MBA4 in the degradation of haloacids

Kwok, Sui-yi. January 2007 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2008. / Also available in print.
18

Spéciation de composés organohalogénés constitutifs des AOX issus de la monochloramination des eaux brutes de rivières / Speciation of organohalogen compounds constituting the AOX from monochloraminated river water

Kinani, Aziz 13 October 2017 (has links)
Au cours des dernières années, divers travaux visant à identifier et à quantifier les sous-produits organohalogénés (SPOX) issus du traitement des eaux brutes de rivières à la monochloramine ont été menés. Un effort particulier a été porté sur le suivi des sous-produits organohalogénés réglementés et/ou connus et au paramètre analytique AOX (composés organohalogénés adsorbables sur charbon actif). Ce paramètre permet d’estimer la quantité totale de sous-produits organohalogénés générés.Un état des lieux récent montre qu’en dépit du nombre important de ces composés sur des échantillons d’eau « réels », le pourcentage de ces sous-produits identifiés imputables au traitement à la monochloramine reste très faible.Le travail réalisé dans la thèse s’inscrit dans la continuité des travaux menés par EDF R&D sur la spéciation des SPOX constitutifs d’AOX, selon une démarche analytique interconnectée. Cette dernière a permis la réduction d’incertitudes liées à la manière d’établissement du bilan de matière par (1) la mise en place de protocoles efficaces d’extraction et d’enrichissement des SPOX sur phase solide, (2) le développement de méthodes d’analyse sensibles permettant de doser simultanément plusieurs SPOX ou familles de SPOX connus, (3) la fiabilisation de la méthode de mesure des AOX en améliorant son étape de préparation d’échantillon et le développement d’une méthode d’analyse permettant d’établir le taux d’incorporation des différents halogénures (Cl, Br, I) dans les AOX, et (4) la réalisation d’essais de « screening » non ciblé par GC-MS et LC-MS ainsi que l’analyse en haute résolution par le FT-ICR/MS, pour l’identification des SPOX de haut poids moléculaire.Cette démarche a été appliquée sur des échantillons d’eau réels et a permis un gain de sensibilité par rapport aux méthodes actuelles, ainsi que l’identification de nouveaux SPOX, non répertoriés dans les études antérieures d’EDF R&D. / Over the last years, various studies have been carried out to identify and quantify the organohalogen by-products (OXBPs) resulting from the treatment of river waters with monochloramine. A particular effort was made to monitor the regulated and/or known organohalogen by-products with the analytical parameter AOX (Adsorbable Organic Halides). This parameter estimate the quantity of organohalogen by-products generated.A recent inventory shows that despite the large number of these compounds on "real" water samples, the percentage of these identified by-products attributable to monochloramine treatment remains very low.The thesis project is a continuation of previous studies carried out by EDF R&D on the speciation of OXBPs constituents of AOX, according to an interconnected analytical approach. This latter allowed the reduction of uncertainties related to how the material balance was established : (1) setting up efficient extraction and enrichment protocols for OXBPs on solid phase, (2) the development of sensitive analytical methods for monitoring simultaneously several known OXBPs, (3) improving the reliability of the AOX measurement method by improving its sample preparation step and developing a method of analyzing Analysis in order to establish the rate of incorporation of the various halides (Cl, Br, I) in AOX, and (4) non-targeted screening tests by GC-MS and LC-MS, as well as analysis in high resolution by FT-ICR/MS for the identification of OXBPs with high molecular weight.This approach was applied to real water samples and increased sensitivity to current methods, as well as the identification of new OXBPs not listed in previous EDF R&D studies.
19

Base-promoted aryl carbon-halogen bond cleavages by Iridium (III) porphyrins. / CUHK electronic theses & dissertations collection

January 2011 (has links)
Cheung, Chi Wai. / "December 2010." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
20

Selective carbon(CO)-carbon(α) bond activation of ketones by rhodium porphyrin complex and aldehydic carbon-hydrogen bond activation by iridium porphyrin complex. / Selective carbon(carbonyl)-carbon(alpha) bond activation of ketones by rhodium porphyrin complex and aldehydic carbon-hydrogen bond activation by iridium porphyrin complex

January 2013 (has links)
本論文主要探討銠卟啉和銥卟啉絡合物,分別與酮類與醛類進行的鍵活化化學。 / 第一部分主要介紹由β-乙基羥基銠卟啉絡合物(Rh{U+1D35}{U+1D35}{U+1D35}(ttp)CH₂CH₂OH)與酮類進行的羰基碳及α-碳(C(CO)-C(α)) 鍵活化(下稱碳碳鍵活化)。於室溫至50ºC時,在非溶劑的條件下,Rh{U+1D35}{U+1D35}{U+1D35}(ttp)CH₂CH₂OH選擇性地斷裂芳香酮和脂肪酮類的C(CO)-C(α)鍵,生成相對應的銠卟啉酰基絡合物(Rh{U+1D35}{U+1D35}{U+1D35}(ttp)COR, R = 烷基或芳基),產率最高可達80%。作為銠卟啉羥基絡合物(Rh{U+1D35}{U+1D35}{U+1D35}(ttp)OH)的前體,Rh{U+1D35}{U+1D35}{U+1D35}(ttp)CH₂CH₂OH的活性展示出Rh{U+1D35}{U+1D35}{U+1D35}(ttp)OH是碳碳鍵活化的重要中間體。 / 第二部分主要介紹由β-乙基羥基銥卟啉絡合物(Ir{U+1D35}{U+1D35}{U+1D35}(ttp)CH₂CH₂OH)與芳香醛類進行,具選擇性的醛碳氫鍵活化。在160ºC和非溶劑的條件下,Ir{U+1D35}{U+1D35}{U+1D35}(ttp)CH₂CH₂OH與芳香醛類反應,生成相對應的銥卟啉酰基絡合物(Ir{U+1D35}{U+1D35}{U+1D35}(ttp)COAr)作為碳氫鍵活化產物,產率最高可達72%。銥卟啉羥基絡合物(Ir{U+1D35}{U+1D35}{U+1D35}(ttp)OH)和乙烯配位銥卟啉絡合正離子((CH₂=CH₂)Ir{U+1D35}{U+1D35}{U+1D35}(ttp)⁺)被推斷為醛碳氫鍵活化的可能中間體。 / This research focuses on the bond activation chemistry by rhodium and iridium porphyrin complexes with ketones and aldehyde respectively. / Part 1 describes the C(CO)-C(α) bond activation (CCA) of ketones by Rh{U+1D35}{U+1D35}{U+1D35}(ttp)CH₂CH₂OH (ttp = 5,10,15,20-tetratolylporphyrinato dianion). Rh{U+1D35}{U+1D35}{U+1D35}(ttp)- CH₂CH₂OH selectively cleaved the C(CO)-C(α) bond of aromatic and aliphatic ketones in solvent-free conditions at room temperature to 50ºC, giving the corresponding rhodium(III) porphyrin acyls (Rh{U+1D35}{U+1D35}{U+1D35}(ttp)COR, R = alkyl or aryl) up to 80% yield. The activity of the Rh{U+1D35}{U+1D35}{U+1D35}(ttp)OH precursor, Rh{U+1D35}{U+1D35}{U+1D35}(ttp)CH₂CH₂OH, demonstrates Rh{U+1D35}{U+1D35}{U+1D35}(ttp)OH as the key intermediate in the CCA of ketones. / [With images]. / Part 2 describes the selective aldehydic carbon-hydrogen bond activation (CHA) of aryl aldehydes by Ir{U+1D35}{U+1D35}{U+1D35}(ttp)CH₂CH₂OH. Ir{U+1D35}{U+1D35}{U+1D35}(ttp)CH₂CH₂OH reacted with aryl aldehydes in solvent-free conditions at 160ºC to give the corresponding iridium(III) porphyrin acyls (Ir{U+1D35}{U+1D35}{U+1D35}(ttp)COAr) as the CHA products up to 72% yield. Ir{U+1D35}{U+1D35}{U+1D35}(ttp)OH and (CH₂=CH₂)Ir{U+1D35}{U+1D35}{U+1D35}(ttp)⁺ were proposed as the possible intermediate for the CHA reaction. / [With images]. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Chan, Chung Sum. / "November 2012." / Thesis (M.Phil.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references. / Abstracts also in Chinese. / Abstract --- p.i / Acknowledgement --- p.iii / Table of Contents --- p.iv / Abbreviations --- p.vii / Structural Abbreviations of Porphyrin --- p.viii / Chapter Part 1 --- Carbon-Carbon Bond Activation of Ketones with Rhodium(III) Porphyrin β-Hydroxyethyl --- p.1 / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Properties of Ketones --- p.1 / Chapter 1.2 --- Carbon(CO)-Carbon(α) Bond Activation (CCA) of Ketones --- p.2 / Chapter 1.2.1 --- CCA of Ketones by Transition Metal Complexes --- p.2 / Chapter 1.2.2 --- CCA of Ketones by Metalloporphyrins --- p.5 / Chapter 1.3 --- Porphyrin Ligands and Rhodium(III) Porphyrins --- p.7 / Chapter 1.3.1 --- Porphyrin Ligands --- p.7 / Chapter 1.3.2 --- Rhodium(III) Porphyrins --- p.8 / Chapter 1.4 --- Rhodium(III) Porphyrin Hydroxide --- p.10 / Chapter 1.4.1 --- Nature of Bonding in Late Transition Metal Hydroxides --- p.10 / Chapter 1.4.1.1 --- Hard-Soft Acid-Base principle --- p.11 / Chapter 1.4.1.2 --- dπ-pπ Interaction Model --- p.11 / Chapter 1.4.1.3 --- E-C Model --- p.12 / Chapter 1.4.2 --- Attempted Preparation of Rhodium(III) Porphyrin Hydroxides --- p.13 / Chapter 1.4.3 --- Chemistry of Rhodium(III) Porphyrin Hydroxides --- p.15 / Chapter 1.5 --- Rhodium(III) Porphyrin β-hydroxyethyl as Rhodium(III) Hydroxide Precursor --- p.18 / Chapter 1.6 --- Objective --- p.20 / Chapter Chapter 2 --- Carbon-Carbon Bond Activation of Ketones with Rhodium(III) Porphyrin β-Hydroxyethyl --- p.21 / Chapter 2.1 --- Preparation of Starting Materials --- p.21 / Chapter 2.1.1 --- Synthesis of Porphyrin --- p.21 / Chapter 2.1.2 --- Synthesis of Rhodium(III) Porphyrins --- p.21 / Chapter 2.2 --- CCA of Diisopropyl Ketone by Rh{U+1D35}{U+1D35}{U+1D35}(ttp)CH₂CH₂OH --- p.22 / Chapter 2.3 --- Optimization of Reaction Conditions --- p.22 / Chapter 2.3.1 --- Atmosphere Effect --- p.22 / Chapter 2.3.2 --- PPh3 Effect --- p.23 / Chapter 2.3.3 --- Solvent Effect --- p.24 / Chapter 2.4 --- Substrate Scope --- p.26 / Chapter 2.4.1 --- CCA of Isopropyl Ketones --- p.26 / Chapter 2.4.2 --- CCA of Non-Isopropyl Ketones --- p.28 / Chapter 2.5 --- Proposed Mechanism --- p.29 / Chapter 2.6 --- Comparison on CCA of Ketones by Different Rh{U+1D35}{U+1D35}{U+1D35}(por)OH Sources --- p.31 / Chapter 2.6.1 --- Reaction Conditions --- p.31 / Chapter 2.6.2 --- Substrate Scope --- p.32 / Chapter 2.6.3 --- Regioselectivity --- p.33 / Chapter 2.7 --- Comparison on Bond Activation of Carbonyl Compounds by Rhodium Porphyrin β-Hydroxyethyl --- p.34 / Chapter 2.8 --- CCA of Ketones with Ir{U+1D35}{U+1D35}{U+1D35}(ttp)CH₂CH₂OH --- p.36 / Chapter 2.9 --- Conclusion --- p.37 / Chapter Chapter 3 --- Experimental Sections --- p.39 / References --- p.54 / List of Spectra I --- p.59 / Spectra --- p.60 / Chapter Part 2 --- Aldehydic Carbon-Hydrogen Bond Activation with Iridium(III) Porphyrin β-Hydroxyethyl --- p.63 / Chapter Chapter 1 --- Introduction --- p.63 / Chapter 1.1 --- Properties of Aldehydes --- p.63 / Chapter 1.2 --- Carbon-Hydrogen Bond Activation (CHA) of Aldehydes --- p.64 / Chapter 1.2.1 --- CHA of Aldehydes by Transition Metal Complexes --- p.64 / Chapter 1.2.2 --- Aldehydic CHA by Metalloporphyrins --- p.74 / Chapter 1.3 --- Iridium(III) Porphyrins --- p.77 / Chapter 1.4 --- Iridium(III) Porphyrin Hydroxide --- p.78 / Chapter 1.4.1 --- Attempted Preparation of Iridium(III) Porphyrin Hydroxides --- p.78 / Chapter 1.4.2 --- Chemistry of Iridium(III) Porphyrin Hydroxides --- p.81 / Chapter 1.5 --- Iridium(III) Porphyrin β-hydroxyethyl as Iridium(III) Hydroxide Precursor --- p.83 / Chapter 1.6 --- Objective --- p.85 / Chapter Chapter 2 --- Aldehydic Carbon-Hydrogen Bond Activation with Iridium(III) Porphyrin β-Hydroxyethyl --- p.86 / Chapter 2.1 --- Preparation of Iridium(III) Porphyrins --- p.86 / Chapter 2.2 --- Aldehydic CHA of Benzaldehyde by Ir{U+1D35}{U+1D35}{U+1D35}(ttp)CH₂CH₂OH --- p.87 / Chapter 2.3 --- Optimization of Reaction Conditions --- p.87 / Chapter 2.3.1 --- Temperature Effect --- p.87 / Chapter 2.3.2 --- Solvent Effect --- p.88 / Chapter 2.3.3 --- PPh₃ Effect --- p.90 / Chapter 2.4 --- Substrate Scope --- p.93 / Chapter 2.5 --- Proposed Mechanism --- p.94 / Chapter 2.6 --- Conclusion --- p.96 / Chapter Chapter 3 --- Experimental Sections --- p.97 / References --- p.108 / List of Spectra II --- p.112 / Spectra --- p.112

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