Huang, Yingsi. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 105-106). / Abstracts in English and Chinese. / Abstract --- p.i / Abstract (in Chinese) --- p.iii / Acknowledgment --- p.v / Table of Contents --- p.vii / List of Figures --- p.x / List of Schemes --- p.xv / List of Tables --- p.xv / Abbreviations --- p.xvi / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Natural Photosynthesis --- p.1 / Chapter 1.1.1 --- Process of Natural Photosynthesis --- p.1 / Chapter 1.1.2 --- Chromophores of Natural Photosynthesis --- p.2 / Chapter 1.1.3 --- Mechanism of Natural Photosynthesis --- p.3 / Chapter 1.2 --- Development of Artificial Photosynthetic Models --- p.4 / Chapter 1.2.1 --- Models Based on Porphyrins and Fullerene Derivatives --- p.6 / Chapter 1.2.2 --- Models Based on Boron Dipyrromethenes (BDPs) --- p.12 / Chapter 1.2.3 --- Applications of Artificial Photosynthetic Models --- p.14 / Chapter 1.3 --- Boron Dipyrromethenes (BDPs) --- p.15 / Chapter 1.3.1 --- General --- p.15 / Chapter 1.3.2 --- Energy Transfer Systems Based on BDPs --- p.16 / Chapter 1.3.2.1 --- BDPs as Energy Donors --- p.16 / Chapter 1.3.2.2 --- BDPs as Energy Acceptors --- p.22 / Chapter 1.3.2.3 --- BDPs as both Energy Donors and Acceptors --- p.26 / Chapter 1.4 --- References --- p.30 / Chapter Chapter 2 --- "Synthesis, Characterization, and Photophysical Properties of the Triad BDP-SiPc-MSBDP as an Artificial Photosynthetic Model" --- p.35 / Chapter 2.1 --- Introduction --- p.35 / Chapter 2.2 --- Results and Discussion --- p.38 / Chapter 2.2.1 --- Preparation and Characterization --- p.38 / Chapter 2.2.2 --- Electronic Absorption and Photophysical Properties --- p.45 / Chapter 2.2.3. --- Electrochemical Properties --- p.50 / Chapter 2.3 --- Conclusion --- p.52 / Chapter 2.4 --- Experimental Section --- p.52 / Chapter 2.4.1 --- General --- p.52 / Chapter 2.4.2 --- Photophysical Studies --- p.53 / Chapter 2.4.3 --- Electrochemical Studies --- p.54 / Chapter 2.4.4 --- Synthesis --- p.54 / Chapter 2.5 --- References --- p.58 / Chapter Chapter 3 --- "Synthesis, Characterization, and Photophysical Properties of the Pentad SiPc(MSBDP-BDP)2" --- p.60 / Chapter 3.1 --- Introduction --- p.60 / Chapter 3.2 --- Results and Discussion --- p.61 / Chapter 3.2.1 --- Preparation and Characterization --- p.61 / Chapter 3.2.2 --- Ground-State Electronic Properties and Energy Transfer Processes of BDP-MSBDP 3.3 --- p.66 / Chapter 3.2.3 --- Photophysical Properties of the Pentad SiPc(MSBDP-BDP)2 (3.1) --- p.68 / Chapter 3.2.4 --- Electrochemical Properties of the Pentad SiPc(MSBDP-BDP)2 (3.1) --- p.73 / Chapter 3.3 --- Conclusion --- p.75 / Chapter 3.4 --- Experimental Section --- p.75 / Chapter 3.4.1 --- General --- p.75 / Chapter 3.4.2 --- Synthesis --- p.75 / Chapter 3.5 --- References --- p.80 / Chapter Chapter 4 --- Novel Artificial Photosynthetic Models Constructed by Supramolecular Methodology --- p.81 / Chapter 4.1 --- Introduction --- p.81 / Chapter 4.2 --- Results and Discussion --- p.83 / Chapter 4.2.1 --- Preparation and Characterization --- p.83 / Chapter 4.2.2 --- Ground-state Electronic Properties and Energy Transfer Process of Compound 4.6 --- p.86 / Chapter 4.2.3 --- Formation and Properties of Assembly 4.1 (ZnTPP.4.6) --- p.89 / Chapter 4.2.4 --- Formation and Properties of Assembly 4.2 [Ru(CO)TPP.4.6] --- p.95 / Chapter 4.2.5 --- Comparison of the Assemblies 4.1 and 4.2 --- p.100 / Chapter 4.3 --- Conclusion --- p.101 / Chapter 4.4 --- Experimental Section --- p.101 / Chapter 4.4.1 --- General --- p.101 / Chapter 4.4.2 --- Synthesis --- p.102 / Chapter 4.5 --- References --- p.105

本论文主要研究了各种可见光光催化剂的合成。包括了Cu₂S，CuO/ZnO复合物以及钒酸根掺杂的磷酸银材料。论文讨论了这些光催化剂的性质与光催化活性，机理同应用也在本文中进行了探讨。 / 首先，发现并合成了硫化亚铜十四面体纳米粒子。研究中发现三正辛基膦对硫化亚铜多面体的形成是必需的。得到的硫化亚铜多面体具有暴露的罕见的面。通过对其光电活性的研究发现，相对于常见的硫化亚铜六边形片状纳米粒子，这种多面体具有5倍以上的活性。 / 其次，异质结构的CuO/ZnO复合材料通过光化学沉积合成。在这两种半导体的接触面形成了p-n结，促进了电子在两者间的传递。在荧光谱图中发现，因电子空穴淬灭引发的荧光峰消失了。这代表由于异质节的形成电荷分离的效率大大提高，从而光催化的效率也得到了很好的提高。 / 最后，含氧根离子作为一种新型的掺杂材料被用于提高磷酸银的性质。磷酸银光解水的能力经过掺杂后得到了显著提高。同时，其在可见光下的稳定性也获得了很大的提高。含氧根离子掺杂物对于磷酸银材料的性质改变及机理在文中都进行了探讨。 / This thesis focuses primarily on the development of visible-light-driven photocatalysts. These include Cu₂S, CuO/ZnO composites and vanadate doped Ag₃PO₄. The property and activity of the materials were studied. The application and mechanism of the enhancement were also explored. / Firstly, 14-facet polyhedra Chalcocite Cu₂S Nanocrystals were synthesized utilizing solvothermal method. It was found that the presence of trio-n-octylphosphine was essential for the exposure of unconventional faces. Studies of the photoelectrochemical performance have indicated that the polyhedra bounded by facets exhibit much higher activities than Cu₂S hexagonal plates with only facets. / Secondly, a heterostructure of CuO/ZnO was fabricated via photochemical deposition. The formation of p-n junction improved the visible light absorption property of ZnO. Photoluminescence spectra showed diminished peaks caused by recombination of excited electrons and holes in the semiconductor which demonstrated that the heterostructure facilitated the charge separation and thus enhanced the photocatalytic activity. / Thirdly, an oxoanion doping method was employed to improve the properties of Ag₃PO₄. The water oxidation ability was found to be higher than the pure Ag₃PO₄. The doping method was proven to be effective in both improving activity and durability. The mechanism of the doping method was also discussed. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Li, Yecheng. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 71-77). / Abstracts also in Chinese. / Abstract (Chinese) --- p.i / Abstract --- p.ii / Acknowledgement --- p.iii / List of Figures --- p.v / Table of Contents --- p.viii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1. --- Basic Principles of Photocatalysis --- p.1 / Chapter 1.2. --- Strategies to Develop Visible-light-driven Photocatalysts --- p.4 / Chapter 1.2.1. --- Native visible-light-driven photocatalysts --- p.4 / Chapter 1.2.2. --- Ion substitution (doping) --- p.6 / Chapter 1.2.3. --- Solid solution photocatalysts --- p.10 / Chapter 1.2.4. --- Dye sensitization to harvest visible light --- p.13 / Chapter 1.3. --- Strategies to Enhance Photocatalytic Activity --- p.15 / Chapter 1.3.1. --- Interface engineering --- p.15 / Chapter 1.3.2. --- Band gap engineering (Tuning distribution of dopants) --- p.17 / Chapter 1.3.3. --- Crystal structure and morphology engineering --- p.19 / Chapter 1.3.4. --- Cocatalyst loading --- p.23 / Chapter 1.4. --- Summary --- p.25 / Chapter 1.5. --- Objective of the Thesis --- p.25 / Chapter Chapter 2 --- Facet Effect of Copper(I) Sulfide Nanocrystals on Photoelectrochemical Properties --- p.28 / Chapter 2.1. --- Introduction --- p.28 / Chapter 2.2. --- Experimental --- p.30 / Chapter 2.2.1. --- Synthesis --- p.30 / Chapter 2.2.2. --- Characterization --- p.30 / Chapter 2.2.3. --- Photoelectrochemical performance analysis --- p.31 / Chapter 2.3. --- Results and Discussion --- p.32 / Chapter 2.4. --- Conclusions --- p.40 / Chapter Chapter 3 --- CuO-ZnO Composites for Enhanced Photoelectrochemical Performance --- p.41 / Chapter 3.1. --- Introduction --- p.41 / Chapter 3.2. --- Experimental --- p.42 / Chapter 3.2.1. --- Synthesis --- p.42 / Chapter 3.2.2. --- Characterization --- p.43 / Chapter 3.2.3. --- Photoelectrochemical performance analysis --- p.44 / Chapter 3.3. --- Results and Discussion --- p.45 / Chapter 3.4. --- Conclusions --- p.56 / Chapter Chapter 4 --- Vanadate Doped Ag₃PO₄ and Its Enhanced Photoactivity and Durability --- p.57 / Chapter 4.1. --- Introduction --- p.57 / Chapter 4.2. --- Experimental --- p.59 / Chapter 4.2.1. --- Synthesis --- p.59 / Chapter 4.2.2. --- Characterization --- p.59 / Chapter 4.2.3. --- Oxygen evolution tests --- p.60 / Chapter 4.3. --- Results and Discussion --- p.61 / Chapter 4.4. --- Conclusions --- p.68 / Chapter Chapter 5 --- Summary --- p.69 / Reference --- p.71

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氟硼熒二吡咯染料是一類多功能的熒光材料，並得到了廣泛的應用。本論文的目標是探索此類染料以及它的氮雜類似物作為探測重金屬離子的熒光探針，非線性光學材料和構建人工光合作用模型的潛力。 本論文報導了一系列氟硼熒二吡咯染料和它的氮雜類似物的分子設計，合成，光學性質以及在相關領域的應用。 / 第一章簡單的概述了氟硼熒二吡咯染料的合成，光學性質和作為重金屬熒光探針和非線性光學材料的應用。然後詳細概述了氮雜氟硼熒二吡咯染料的發展，合成，光學性質，以及其在生物醫藥和材料科學領域的潛在應用。 / 第二章報導了一個對銅和汞二價離子具有高選擇性比色性識別的近紅外熒光探針。 這個探針以雙邊苯乙烯修飾的氟硼熒二吡咯染料為螢光團，並進一步修飾兩個二（三唑）胺的識別位點。在體積比為1 比1 的乙腈水溶液中，當加入銅和汞二價離子時，這個探針的吸收和熒光波長表現出不同程度的藍移，而且這個變化可以被肉眼觀察到。這是因為分子內的電荷傳遞過程被抑制的結果。另外，通過其熒光變化的工作曲線法，銅二價離子與此探針具有2 比1 的結合比例。進一步研究表明它們表現出較大的結合常數（(6.2 ± 0.6) × 10⁹ M⁻²），是汞二價離子的結合常數的六倍。 / 另外，除了分子內電荷傳遞的機理，光致電子轉移和熒光共振能量傳遞也是兩種常用的設計熒光探針的機理。第三章報導了兩個基於光致電子轉移和熒光共振能量傳遞的有高效選擇性的汞二價離子熒光探針。 我們使用電子吸收和熒光光譜的方法研究了他們之間的結合性能。其中一個探針在中間的位置連接了一個二（三唑）胺的結合位點，並對汞二價離子表現出很高的响應性。另一個探針進一步引入了兩個羅丹明熒光團到氟硼熒二吡咯染料上，於是當接觸到汞二價離子時，激發的氟硼熒二吡咯染料的能量將高效的傳遞到羅丹明上，從而表現出顯著的光譜的變化。 / 第四章描述了一系列含有兩個電子供體和推拉結構的氟硼熒以及氮雜氟硼熒二吡咯染料的設計，合成，以及作為非線性光學材料的潛力。通過薗頭偶合反應，兩個對位二苯胺基苯乙炔基或對位二甲氨基苯乙炔基被連接到了該染料的2 和6 位上。線性的吸收和熒光研究表明那些化合物表現出溶劑效應。 它們在甲苯中雙光子吸收的性能通過用雙光子激發熒光光譜的方法進行了研究。另外，對於推拉電子的一系類化合物，推電子的對位二甲氨基苯乙炔基和拉電子的對位硝基苯乙炔基分別連接到了該染料的2 和6 位上。這些化合物的光學和電化學性能得到了詳細的研究。在氯仿溶液中，它們的二價非線性光學性質通過電場誘導的二次諧波的方法進行了研究，其在1907 納米的標量積μ.β在94 ×10⁻⁴⁸ 到330 × 10⁻⁴⁸ esu 之間，並隨著3 和5 位取代基的不同而變化。 / 第五章報導了一個基於單邊苯乙烯氟硼熒二吡咯染料和富勒烯雙修飾的氮雜氟硼熒二吡咯染料的人工光合作用模型。這個三元體系的分子內光誘導的過程使用穩態的光學方法進行了研究。當激發單邊苯乙烯氟硼熒二吡咯染料部分時，這個被激發的部分會將能量傳遞給氮雜氟硼熒二吡咯染料，然後進一步的將電子傳遞給富勒烯。運用飛秒瞬態鐳射的方法，它們之間在苯睛中電子重排的速率是7.00 × 10⁸ s⁻¹，從而得到電荷分離態的壽命是1.47 納秒。 / 作為上一個工作的拓展，第六章報導了兩個或四個甲基化環糊精修飾的氮雜氟硼熒二吡咯染料與四磺酸基卟啉和其鋅卟啉，以及兩個帶正電的單邊苯乙烯修飾的氟硼熒二吡咯染料在水中的相互作用。使用各種光學方法，我們研究了它們的結合過程以及能量或者電子的傳遞過程。最後，四磺酸基卟啉， 環糊精修飾的氮雜氟硼熒二吡咯染料，以及單邊修飾的氟硼熒二吡咯染料在水溶液中進行了自組裝。當激發卟啉時，能量高效的傳遞到氮雜氟硼熒二吡咯染料上，接著電子從單邊修飾的氟硼熒染料傳遞到氮雜氟硼熒二吡咯染料上。因此，這個多重的超分子體系是一個很好的光合作用模型。 / 第七章和第八章分別闡述了前面幾章的實驗部分和引用文獻。 / 論文的最後一部分附上了所有新化合物的核磁共振氫譜和碳譜圖。 / Boron dipyrromethenes (BODIPYs) are versatile functional materials for a wide range of applications. This research work aims to explore the potential of these compounds and their aza analogues as fluorescent probes for heavy metal ions, nonlinear optical materials, and building blocks of artificial photosynthetic models. This thesis describes the molecular design, synthesis, spectroscopic characterization, and photophysical properties of several series of BODIPYs and aza-BODIPYs, as well as their potential applications in these areas. / Chapter 1 gives a brief overview of BODIPYs, focusing on their synthesis, spectroscopic properties, and applications as fluorescent probes for heavy metal ions and nonlinear optical materials. It then reviews the historical development, syntheses, and spectroscopic properties of their aza analogues. The potential applications of aza-BODIPYs in biomedicine and materials science are also discussed at the end of this chapter. / In Chapter 2, a highly selective colorimetric and near-infrared fluorescent probe for Cu²⁺ and Hg²⁺ ions is reported, which is based on a distyryl BODIPY with two bis(1,2,3-triazole)amino receptors. The compound selectively binds to Cu²⁺ and Hg²⁺ ions in CH₃CN/H₂O (1:1 v/v) giving remarkably blue-shifted electronic absorption and fluorescence bands as a result of inhibition of the intramolecular charge transfer (ICT) process upon binding. The color changes can be easily seen by the naked eye. The binding stoichiometry between this probe and Cu²⁺ ion has been determined to be 1:2 by a Job’s plot of the fluorescence data with a binding constant of (6.2 ± 0.6) × 10⁹ M⁻². The corresponding value for Hg²⁺ ion is about six-fold smaller. / In addition to the ICT mechanism, photoinduced electron transfer (PET) and fluorescence resonance energy transfer (FRET) are another two useful mechanisms for design of fluorescent probes. Chapter 3 reports two highly selective and sensitive BODIPY-based fluorescent probes for Hg²⁺ ion based on PET and FRET mechanisms. Their binding properties have been investigated by using electronic absorption and steady-state fluorescence spectroscopic methods. The probe with a bis(1,2,3-triazole)amino receptor at the meso position is highly responsive toward Hg²⁺ ion. By introducing two rhodamine B moieties to the BODIPY core, FRET occurs from the excited BODIPY to rhodamine B in a highly effective manner upon binding to Hg²⁺ ion, regarding to remarkable spectral changes. / Chapter 4 presents a series of BODIPY and aza-BODIPY derivatives bearing a donor-π-donor or push-pull structure as nonlinear optical materials. The donor-π-donor derivatives have been prepared by connecting 4-(diphenylamino)phenylethynyl or 4-(dimethylamino)phenylethynyl moieties to the 2- and 6-positions of the π systems through Sonogashira coupling reactions. The linear optical absorption and fluorescence properties of these compounds have been found to be solvent-dependent. Their two-photon absorption properties have also been measured in toluene by two-photon fluorescence excitation method. For the push-pull series, an electron-donating 4-(dimethylamino)phenylethynyl group and an electron-withdrawing 4-nitrophenylethynyl group have been added to the 2- and 6-positions of the BODIPY core. The spectroscopic and electrochemical properties of these compounds have been studied. Their second-order nonlinear optical properties have also been examined by electric-field-induced second-harmonic generation method in CHCl₃. The values of the dot product μ.β are in the range from 94 × 10⁻⁴⁸ to 330 × 10⁻⁴⁸ esu at 1907 nm, depending on the substituents at the 3- and 5-positions. / Chapter 5 describes the synthesis and characterization of an artificial photosynthetic model in which an aza-BODIPY core is covalently linked to a monostyryl BODIPY component and a fullerene (C₆₀) unit. The photoinduced intramolecular processes of this triad and the model compounds have been studied in detail by steady-state and time-resolved spectroscopic methods. Upon excitation at the monostyryl BODIPY moiety, excitation energy transfer occurs to the aza-BODIPY core, which is followed by an electron transfer to the C₆₀ unit. From the femtosecond transient absorption studies, the rate constant of charge recombination has been determined to be 7.00 × 10⁸ s⁻¹ in benzonitrile, giving a lifetime of 1.47 ns for the charge-separated state. / As an extension, Chapter 6 presents related supramolecular systems in which an aza-BODIPY derivative bearing two or four permethylated β-cyclodextrin moieties binds to metal-free and zinc(II) tetrasulfonated porphyrins, as well as two cationic monostyryl BODIPYs in water. The complexation of these components has been studied by various spectroscopic methods. The resulting host-guest complexes exhibit efficient energy and/or electron transfer depending on the nature of the guests. A novel mixed array of metal-free porphyrin, aza-BODIPY, and monostyryl BODIPY has also been assembled. Upon excitation at the porphyrin unit, singlet-singlet energy transfer occurs to the aza-BODIPY core, which then obtains an electron from the monostyryl BODIPY moieties. This supramolecular hetero-array thus also serves as an artificial photosynthetic model. / Chaper 7 gives the experimental details for the work described in the preceedingchapters. All the references cited herein are given in Chapter 8. / ¹H and ¹³C{¹H} NMR spectra of all the new compounds are given in the Appendix. / 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. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Shi, Wenjing. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 204-220). / Abstracts also in Chinese. / Table of Contents --- p.I / Acknowledgment --- p.VII / Abstract --- p.IX / Abstract (in Chinese) --- p.XIII / Abbreviations --- p.XV / List of Figures --- p.XXI / List of Tables --- p.XXXII / List of Schemes --- p.XXXIV / Publication Related to This Thesis --- p.XXXVI / Chapter Chapter 1 --- Introduction / Chapter 1.1 --- General --- p.1 / Chapter 1.2 --- Synthesis, Reactivity, and Spectroscopic Properties of BODIPYs --- p.2 / Chapter 1.2.1 --- Synthesis of BODIPYs --- p.2 / Chapter 1.2.2 --- Reactivity of BODIPYs --- p.5 / Chapter 1.2.3 --- Spectroscopic Properties of Selected BODIPYs --- p.6 / Chapter 1.3 --- Applications of BODIPYs --- p.9 / Chapter 1.3.1 --- BODIPYs as Fluorescent Probes for Heavy Metal Ions --- p.9 / Chapter 1.3.2 --- BODIPYs as Two-Photon Absorbing Materials --- p.14 / Chapter 1.3.2.1 --- General for Two-Photon Absorption --- p.14 / Chapter 1.3.2.2 --- Selected Examples of TPA Materials --- p.15 / Chapter 1.4 --- Aza-BODIPYs: Aza Analogues of BODIPYs --- p.18 / Chapter 1.4.1 --- General --- p.18 / Chapter 1.4.2 --- Synthesis and Reactivity of Aza-BODIPYs --- p.18 / Chapter 1.4.3 --- Spectroscopic Properties of Aza-BODIPYs --- p.21 / Chapter 1.4.4 --- Applications of Aza-BODIPYs --- p.29 / Chapter 1.4.4.1 --- Aza-BODIPYs as Artificial Photosynthetic Models --- p.29 / Chapter 1.4.4.2 --- Aza-BODIPYs as Fluorescent Probes --- p.33 / Chapter 1.4.4.3 --- Aza-BODIPYs as Photosensitizers and Imaging Probes --- p.37 / Chapter 1.4.4.4 --- Other Applications --- p.39 / Chapter 1.5 --- Objectives of this Study --- p.41 / Chapter Chapter 2 --- A Highly Selective Colorimetric and Fluorescent Probe for Cu²⁺ and Hg²⁺ Ions Based on a Distyryl BODIPY with Two Bis(1,2,3-triazole)amino Receptors / Chapter 2.1 --- Introduction --- p.42 / Chapter 2.2 --- Results and Discussion --- p.43 / Chapter 2.2.1 --- Synthesis and Characterization --- p.43 / Chapter 2.2.2 --- Metal Sensing Properties --- p.46 / Chapter 2.2.3 --- Binding Properties --- p.48 / Chapter 2.2.3.1 --- Binding Properties of 2.10 with Cu²⁺ Ion --- p.48 / Chapter 2.2.3.2 --- Binding Properties of 2.10 with Hg²⁺ Ion --- p.52 / Chapter 2.3 --- Conclusion --- p.55 / Chapter Chapter 3 --- Detection of Hg²⁺ Ion with BODIPY-Based Fluorescent Probes Substituted with a Bis(1,2,3-triazole)amino Receptor / Chapter 3.1 --- Introduction --- p.56 / Chapter 3.2 --- Results and Discussion --- p.57 / Chapter 3.2.1 --- Molecular Design, Synthesis, and Characterization --- p.58 / Chapter 3.2.2 --- Metal Binding Properties of 3.6 --- p.61 / Chapter 3.2.3 --- Metal Binding Properties of 3.7 --- p.66 / Chapter 3.2.4 --- Fluorescence Resonance Energy Transfer in 3.7 --- p.72 / Chapter 3.3 --- Conclusion --- p.73 / Chapter Chapter 4 --- Synthesis and Nonlinear Optical Properties of BODIPY and Aza-BODIPY Derivatives / Chapter 4.1 --- Introduction --- p.74 / Chapter 4.2 --- Results and Discussion --- p.75 / Chapter 4.2.1 --- Synthesis of D-π-D BODIPY and Aza-BODIPY Derivatives --- p.75 / Chapter 4.2.2 --- Synthesis of Push-Pull BODIPY Derivatives --- p.81 / Chapter 4.2.3 --- Linear Electronic Absorption and Fluorescence Properties of D-π-D BODIPY and Aza-BODIPY Derivatives --- p.84 / Chapter 4.2.4 --- Electrochemical Properties of D-π-D BODIPY Derivatives --- p.88 / Chapter 4.2.5 --- Two-Photon Absorption Properties of D-π-D BODIPY and Aza-BODIPY Derivatives --- p.90 / Chapter 4.2.6 --- Linear Electronic Absorption and Fluorescence Properties of Push-Pull BODIPY Derivatives --- p.93 / Chapter 4.2.7 --- Electrochemical Properties of Push-Pull BODIPY Derivatives --- p.96 / Chapter 4.2.8 --- Second-Order Nonlinear Optical Properties of Push-Pull BODIPY Derivatives --- p.97 / Chapter 4.3 --- Conclusion --- p.99 / Chapter Chapter 5 --- Photosynthetic Antenna-Reaction Center Mimicry with a Covalently Linked Monostyryl Boron Dipyrromethene-Aza Boron Dipyrromethene-C₆₀ Triad / Chapter 5.1 --- Introduction --- p.101 / Chapter 5.2 --- Results and Discussion --- p.103 / Chapter 5.2.1 --- Synthesis --- p.103 / Chapter 5.2.2 --- Steady-State Electronic Absorption and Fluorescence Properties --- p.105 / Chapter 5.2.3 --- Electrochemical Properties and Energy Levels --- p.109 / Chapter 5.2.4 --- Transient Absorption Studies --- p.112 / Chapter 5.2.4.1 --- Femtosecond Transient Absorption Studies --- p.112 / Chapter 5.2.4.2 --- Nanosecond Transient Absorption Studies --- p.117 / Chapter 5.2.5 --- Energy-Level Diagrams --- p.119 / Chapter 5.3 --- Conclusion --- p.121 / Chapter Chapter 6 --- Formation and Photoinduced Processes of the Host-Guest Complexes of β-Cyclodextrin-Conjugated Aza-BODIPYs with Tetrasulfonated Porphyrins and Monostyryl BODIPYs / Chapter 6.1 --- Introduction --- p.122 / Chapter 6.2 --- Results and Discussion --- p.123 / Chapter 6.2.1 --- Synthesis and Characterization --- p.123 / Chapter 6.2.2 --- Host-Guest Complexes of 6.3 with Tetrasulfonated Porphyrins --- p.131 / Chapter 6.2.3 --- Host-Guest Complexes of 6.7 with Tetrasulfonated Porphyrins --- p.141 / Chapter 6.2.4 --- Host-Guest Complexes of 6.7 with Monostyryl BODIPYs --- p.146 / Chapter 6.2.5 --- Host-Guest Complexes of 6.7 with Tetrasulfonated Porphyrins and Monostyryl BODIPYs --- p.154 / Chapter 6.3 --- Conclusion --- p.159 / Chapter Chapter 7 --- Experimental Section / Chapter 7.1 --- General --- p.160 / Chapter 7.2 --- Experiments in Chapter 2 --- p.162 / Chapter 7.2.1 --- Synthesis --- p.162 / Chapter 7.2.2 --- Absorption and Fluorescence Studies --- p.164 / Chapter 7.2.3 --- Determination of Binding Constants (K) --- p.165 / Chapter 7.3 --- Experiments in Chapter 3 --- p.165 / Chapter 7.3.1 --- Synthesis --- p.165 / Chapter 7.3.2 --- Absorption and Fluorescence Studies --- p.169 / Chapter 7.3.3 --- Determination of Binding Constants (K) --- p.169 / Chapter 7.4 --- Experiments in Chapter 4 --- p.170 / Chapter 7.4.1 --- Synthesis --- p.170 / Chapter 7.4.2 --- Electrochemical Measurements --- p.188 / Chapter 7.4.3 --- NLO Measurements --- p.188 / Chapter 7.5 --- Experiments in Chapter 5 --- p.190 / Chapter 7.5.1 --- Synthesis --- p.190 / Chapter 7.5.2 --- Electrochemical Measurements --- p.196 / Chapter 7.5.3 --- Time-Resolved Transient Absorption Measurements --- p.196 / Chapter 7.6 --- Experiments in Chapter 6 --- p.198 / Chapter 7.6.1 --- Synthesis --- p.198 / Chapter 7.6.2 --- Determination of Binding Constants (K) --- p.201 / Chapter 7.6.3 --- Molecular Dynamic Simulation --- p.202 / Chapter 7.6.4 --- Electrochemical Measurements --- p.203 / Chapter Chapter 8 --- References --- p.204 / Appendix --- p.221

Several photosynthetic inhibitors were screened for relative photosynthetic reduction on leaves of greenhouse-grown peach trees. The most effective were 8% Vapor Gard, 10M diurcn, 10⁻³M ABA, and 10⁻³M terbacil, all of which reduced net photosynthesis (Pn) rates by 50% or more by 1 day after treatment without causing excessive phytotoxicity. Of these 4 treatments, terbacil at 10⁻³M gave the most consistent effects; treated leaves re-established near normal Pn rates within a week of treatment. At 1, 3, and 7 days after treatment with terbacil at 10⁻³M, Pn rates were 1.1, 9.0, and 16.6 mgCO₂ dm⁻² hr⁻¹ , respectively, compared with a pretreatment rate of 19.7. Terbacil was applied as limb treatments to bearing peach trees in the field to determine fruit thinning activity. Treatments were: single applications of 1000 or 2000 ppm, double applications a week apart of 1000 ppm, or 2000 followed by 1000 ppm. All treatments significantly reduced fruit number. Fruit drop was 73 to 90% on treated limbs compared to 20% on non-thinned check limbs. Only the single 1000 ppm treatment resulted in fruit size similar to the hand-thinned check, however, all treatments increased fruit size over the non-thinned checks. / M.S.

Thesis (Ph. D.)--University of Hawaii at Manoa, 2003. / Includes bibliographical references (leaves 199-222).

The enormous burning of fossil fuel and deforestation have caused an increase in the atmospheric CO₂ concentration ([CO₂]) during the last century. This will invariably have profound direct and indirect effects on plant carbon metabolism. The majority of research on the effects of CO₂ enrichment on plants are short-term and are done on other crops, but very little have been done on barley. This project aimed to determine the effects of long-term CO₂ enrichment on photosynthesis, growth and grain yield on barley. Hordeum vulgare L. cvs Stirling and Schooner plants were grown from seeds in controlled environment chambers at ambient (350) and elevated (600) μmol molˉ¹ [CO₂]. Measurements of net assimilation rate (NAR), photosynthetic pigments content and growth parameters were started 7 days after germination (DAG) and continued until senescence. The anatomy of matured fully developed leaves was also monitored. Elevated [CO₂l resulted in an increase in NAR in the two cultivars from days 7 until 14, after which the stimulation of NAR of CO₂-enriched plants started to decrease. At the onset of senescence, NAR was almost equal in plants grown under both ambient and elevated [CO₂]. The response of assimilation as a function of internal [CO₂l (C₁) at the end of the experimental period showed a significant decrease in both the initial slope of the A/C₁ curves and the CO₂-saturated photosynthetic rates in the two cultivars. Stirling showed no significant changes in the content of chlorophyll α,chlorophyll б or in total carotenoids. However, Schooner showed a stimulation in chlorophyll α content at day 7, but decreased at day 28. Chlorophyll б and total carotenoids content were not affected by CO₂ enrichment. While total above-ground biomass was not affected by elevated [CO₂] in the two cultivars, total plant height decreased significantly after 14 days in Stirling whereas no significant change occurred in Schooner throughout the experimental period. Leaf area was not significantly affected by CO₂ enrichment in the two cultivars although the leaves in CO₂ enriched plants were slightly shorter. Anatomical studies reveal that leaf thickness was significantly increased by CO₂ enrichment in Stirling, but the increase was not significant in Schooner. Both cultivars did not show any significant effect on chloroplast morphology and ultrastructure as a consequence of elevated CO₂ exposure. No signs of starch accumulation were evident in variety Schooner, but Stirling showed some form of starch accumulation, under increased atmospheric [CO₂]. Elevated CO₂ resulted in a significant reduction by more than 50 % in the number of grain yield per plant in both Stirling and Schooner. Results from this study therefore indicate that CO₂ enrichment will not be beneficial in terms of growth and yield in this important crop.

The transduction of stress signals in plants is known to involve complex hysiological responses. In D. salina a range of stresses results in hyperaccumulation of ft-carotene and an understanding of stress responses in this organism has important biotechnological implications. In this thesis an attempt was made to elucidate the physiological components involved and establish a role for pH in response to high light stress. In order to achieve this the effect of high light stress on photosynthesis and cell productivity was measured. Results showed that photosynthetic carbon assimilation, oxygen evolution and cellular productivity was initially inhibited by exposure to high light intensities, but this inhibition was transient and was overcome by a rapid increase in all three parameters. The response of the carbon pool intermediates was also investigated. It was shown that on exposure to high light ft-carotene declined but then showed a rapid increase after about 4 hours of exposure. It was also demonstrated that the initial loss of ft-carotene was due to loss of this pigment from the photosynthetic pigment bed and that the hyper-accumulation of ft-carotene was due to accumulation of ft-carotene in lipoidal globules located in the chloroplast stroma. It was further demonstrated that there was mass movement of carbon in the xanthophyll cycle shortly after exposure to high light. This was characterized by the de-epoxidation of violaxanthin to antheraxanthin with a further de-epoxidation to zeaxanthin, thereby decreasing the epoxidation state of the cycle. Furthermore, it was shown that there was relocation of carbon from violaxanthin to the plant growth regulator abscisic acid. It was also shown for the first time in D. salina that the production of ft-carotene and operation of the epoxidation state of the xanthophyll cycle has a periodicity which is established after exposure to successive cycles of a light regime. Chlorophyll fluorescence was used together with well established ammonia stress responses to acquire a general overview of energy dissipation from the photosynthetic pigment bed. In conjunction with an understanding of xanthophyll cycle operation during exposure to high light stress it has been possible to establish a relationship between chlorophyll florescence, xanthophyll cycle operation and intracellular pH. It was also shown using chlorophyll fluorescence that after 4 hour exposure to high light a maximum fluorescence peak could no longer be induced indicating a transition at about this point from a state of reversibility to commitment of the full stress response. Nuclear magnetic resonance was used to follow intracellular pH fluxes during exposure to high light. A novel technique was developed for studying photosynthetically active organisms in the dark using nuclear magnetic resonance. These results showed that on exposure to high light stress there is rapid acidification of the chloroplast stroma and to a lesser degree of the acidic vacuole. The pH of these compartments is re-established after about 4 hours which is co-incident with the onset of fl-carotene hyper-accumulation and the loss of the induction of the chlorophyll fluorescence peak indicating an intimate relationship for fl-carotene, chlorophyll fluorescence, xanthophyll cycle operation and pH. The results from this study allow for the proposal of a general physiological stress transduction response mechanism for D. salina which is common for a range of different stresses and where intracellular pH plays a central role.

The position of newly expanded shoot leaves in the canopy of apple trees had significant and similar effects on specific leaf weight (SLW), leaf thickness, length of palisade tissue, and number of cell layers in the palisade tissue. Inside canopy leaves had lower SLW, leaf thickness, palisade length, and number of palisade cell layers than middle and outside leaves at each of six sample dates ranging from late May to early October. Outside canopy leaves had the highest values at all sample dates. Differences in SLW, leaf thickness, and palisade length between inside and outside leaves increased as the season progressed, primarily due to a general increasing trend in outside leaves that developed later in the season. Effects of canopy position on spur leaves were not as great as with shoot leaves. Regression analysis showed SLW to be significantly correlated with leaf thickness and palisade length. / M.S.