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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.
21

Synthesis of π-System-Layered Structures Based on Rigid Scaffolds / 剛直な足場を用いたπ電子系積層構造の構築

Tsuji, Yuichi 24 March 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第18293号 / 工博第3885号 / 新制||工||1596(附属図書館) / 31151 / 京都大学大学院工学研究科高分子化学専攻 / (主査)教授 中條 善樹, 教授 秋吉 一成, 教授 赤木 和夫 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM
22

Self-Assembled Aromatic Conjugated Polymers with Advanced Optical Properties / 自己集積化芳香族共役ポリマーとその高度光学特性

Watanabe, Kazuyoshi 23 March 2015 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第19008号 / 工博第4050号 / 新制||工||1623(附属図書館) / 31959 / 京都大学大学院工学研究科高分子化学専攻 / (主査)教授 赤木 和夫, 教授 中條 善樹, 教授 吉﨑 武尚 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM
23

Precise Control of Highly-Efficient Solid-Emissive Property of Boron Ketoiminate / ケトイミンホウ素錯体の高輝度固体発光特性の精密制御

Suenaga, Kazumasa 25 March 2019 (has links)
付記する学位プログラム名: 充実した健康長寿社会を築く総合医療開発リーダー育成プログラム / 京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21793号 / 工博第4610号 / 新制||工||1718(附属図書館) / 京都大学大学院工学研究科高分子化学専攻 / (主査)教授 田中 一生, 教授 秋吉 一成, 教授 大内 誠 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM
24

DIKETOPYRROLOPYRROLE‐ AND ISOINDIGO‐ BASED CONJUGATED POLYMER FOR ORGANIC ELECTRONIC DEVICE

ZHOU, JIANING 02 May 2021 (has links)
No description available.
25

Synthesis of Conjugated Polymers

Wang, Chao 14 May 2013 (has links)
No description available.
26

Interactions of a zwitterionic thiophene-based conjugated polymer with surfactants

Costa, T., de Azevedo, D., Stewart, Beverly, Knaapila, M., Valente, A.J.M., Kraft, M., Scherf, U., Burrows, H.D. 25 September 2015 (has links)
Yes / In this paper we investigate the optical and structural properties of a zwitterionic poly[3-(N-(4-sulfonato-1-butyl)-N,N-diethylammonium)hexyl-2,5-thiophene] (P3SBDEAHT) conjugated polyelectrolyte (CPE) and its interaction in water with surfactants, using absorption, photoluminescence (PL), electrical conductivity, molecular dynamics simulations (MDS) and small-angle X-ray scattering (SAXS). Different surfactants were studied to evaluate the effect of the head group and chain length on the self-assembly. PL data emphasize the importance of polymer–surfactant electrostatic interactions in the formation of complexes. Nevertheless, conductivity and MDS data have shown that nonspecific interactions also play an important role. These seem to be responsible for the spatial position of the surfactant tail in the complex and, eventually, for breaking-up P3SBDEAHT aggregates. SAXS measurements on P3SBDEAHT-zwitterionic cocamidopropyl betaine (CAPB) surfactant complexes showed a specific structural organization of the system. The CAPB surfactant promotes a structural transition from pure P3SBDEAHT 3-dimensional aggregates (radius of gyration ∼85 Å) to thick cylindrical aggregates (∼20 Å) where all CAPB molecules are associated with the polymer. For molar ratios (in terms of the polymer repeat unit) >1 the SAXS interference maximum of the complexes resembles that of pure CAPB thus suggesting ongoing phase segregation in the formation of a “pure” CAPB phase. / The Coimbra Chemistry Centre is supported by the Fundação para a Ciência e a Tecnologia (FCT), Portuguese Agency for Scientific Research, through the project PEst-OE/QUI/UI0313/2014. TC and BS thank FCT, which has supported this work through Postdoctoral Grants (SFRH/BPD/47181/2008 and SFRH/BPD/82396/2011, respectively). DA acknowledges CNPq, Conselho Nacional de Desenvolvimento Científico e Tecnológico – Brasil, for financial support through the Grant “Bolsista do CNPq – Brasil”. The research leading to the SAXS data has received funding from the European Community's Seventh Framework Programme (FP7/2007–2013) CALIPSO under grant agreement no. 312284.
27

Conjugated Polymer Networks: Synthesis and Properties

Kokil, Akshay 18 July 2005 (has links)
No description available.
28

Novel Conjugated Polymer Prepared by Electrochemical Polymerization as Active Material in Supercapacitor

Chen, Xiaoyi 27 May 2015 (has links)
No description available.
29

Monopolar and Bipolar Membranes in Organic Bioelectronic Devices

Gabrielsson, Erik O. January 2014 (has links)
In the 1970s it was discovered that organic polymers, a class of materials otherwise best know as insulating plastics, could be made electronically conductive. As an alternative to silicon semiconductors, organic polymers offer many novel features, characteristics, and opportunities, such as producing electronics at low costs using printing techniques, using organic chemistry to tune optical and electronic properties, and mechanical flexibility. The conducting organic polymers have been used in a vast array of devices, exemplified by organic transistors, light-emitting diodes, and solar cells. Due to their softness, biocompatibility, and combined electronic and ionic transport, organic electronic materials are also well suited as the active material in bioelectronic applications, a scientific and engineering area in which electronics interface with biology. The coupling of ions and electrons is especially interesting, as ions serve as signal carriers in all living organisms, thus offering a direct translation of electronic and ionic signals. To further enable complex control of ionic fluxes, organic electronic materials can be integrated with various ionic components, such as ion-conducting diodes and transistors. This thesis reports a background to the field of organic bioelectronic and ionic devices, and also presents the integration of ionic functions into organic bioelectronic devices. First, an electrophoretic drug delivery device is presented, capable of delivering ions at high spatiotemporal resolution. The device, called the organic electronic ion pump, is used to electronically control amyloid-like aggregation kinetics and morphology of peptides, and offers an interesting method for studying amyloids in vitro. Second, various ion-conducting diodes based on bipolar membranes are described. These diodes show high rectification ratio, i.e. conduct ions better for positive than for negative applied voltage. Simple ion diode based circuits, such as an AND gate and a full-wave rectifier, are also reported. The AND gate is intended as an addressable pH pixel to regulate for example amyloid aggregation, while the full-wave rectifier decouples the electrochemical capacity of an electrode from the amount of ionic charge it can generate. Third, an ion transistor, also based on bipolar membranes, is presented. This transistor can amplify and control ionic currents, and is suitable for building complex ionic logic circuits. Together, these results provide a basic toolbox of ionic components that is suitable for building more complex and/or implantable organic bioelectronic devices.
30

Processos radiativos e não radiativos em polímeros conjugados emissores de luz. / Radiactive and non-radiactive processes in light-emitting conjugated polymers.

Borges, Célio Aécio Medeiros 08 November 2001 (has links)
O presente trabalho tem como objetivo estudar os processos radiativos e não radiativos em filmes automontados de poli(p-fenileno vinileno), ou PPV, sintetizados e processados no Grupo de Polímeros Prof. Bernhard Gross (GPBG) do IFSC. Além de adquirir conhecimento das propriedades ópticas fundamentais, tais como, os mecanismos básicos responsáveis pela emissão de luz, foram investigados os efeitos da temperatura, da redução da dimensionalidade através do tamanho efetivo de conjugação, das impurezas e dos defeitos estruturais. Foram realizados estudos das propriedades ópticas desse material através das seguintes técnicas espectroscópicas: fotoluminescência (PL), absorção óptica, fotoluminescência por excitação seletiva (PLE). As propriedades estruturais e de superfícies do PPV foram estudadas por infravermelho (IR) e microscopia de força atômica (AFM). A adsorção de camadas alternadas do polímero precursor poli(cloreto de tetrahidrotiofeno de xilideno) (PTHT) e do íon de cadeia longa dodecilbenzenosulfônico (DBS) propiciou a formação de filmes finos com controle de monocamada. A introdução do DBS permitiu a conversão rápida (~10min) destes filmes em PPV a temperaturas muito mais baixas (~100 'graus'C) e com baixa incorporação de defeitos do que aquelas usadas convencionalmente. A boa qualidade estrutural e o alto grau de conjugação destes filmes de PPV foram responsáveis pela boa resolução dos espectros de absorção e emissão, o que permitiu fazer um estudo teórico mais detalhado das propriedades ópticas básicas deste material. Demonstramos que as transições ópticas em polímeros conjugados podem ser descritas pela intensidade da linha de zero-fônon 'I IND.o', pela sua largura 'TAU' e posição 'E IND.o', bem como pelo acoplamento entre os níveis eletrônicos e vibracionais descrito pelo fator Huang-Rhys S. Mostramos que estes parâmetros são profundamente influenciados pela desordem conformacional da cadeia introduzida pela temperatura e pela variação do grau de conjugação. Em especial, consideramos explicitamente a estrutura vibracional do PPV levando-se em conta a aproximação teórica de Franck-Condon de modo a explicar o espectro de emissão experimental. Fomos capazes de reproduzir os espectros de PPV quando consideramos três modos vibracionais efetivos com energias correspondentes em 330, 1164 e 1550 cm-1, que correspondem a estruturas vibracionais intensas do PPV obtidas por espectroscopia de absorção infravermelho e Raman. Do estudo da forma de linha obtivemos pela primeira vez que acoplamento elétron-fônon parametrizado pelo fator S possui diferente dependência com a temperatura para cada um dos modos efetivos. Desta forma, pudemos obter aspectos fundamentais do acoplamento entre os estados eletrônicos e o movimento nuclear em polímeros conjugados que ainda não tinham sido estudados em detalhe na literatura. / The subject of this work is the investigation of the radiactive and non-radiactive processes in poly (p-phenylene vinylene) self-assembled films (PPV), which were synthesized and processed at the Grupo de Polímeros Bernhard Gross (GPBG) of the IFSC. Besides the investigation of the fundamental optical properties, such as the basic mechanisms responsible for light emission, temperatures effects, dimensional reduction, impurities and structural effects were investigated. We investigation the optical properties of this material using the following spectroscopic techniques: photoluminescence (PL), optical absorption and selective excitation photoluminescence (PLE). The structural and superficial properties of PPV were investigated by infrared absorption (IR) and atomic force microscopy (AFM). The adsorption of alternated layers of the precursor polymer poly(xylylidenetetrahydrothiophenium chloride) (PTHT) and the long chain ion dodecylbenzenesulfonate (DBS) permitted the formation of thin films with monolayer control. The introduction of the DBS allowed the rapid conversion (~10min) of this films into PPV at much lower temperatures (~100 oC) and with less defect incorporation than conventional PPV films. The good structural quality and the high conjugation degree of this films were responsible for the high resolution of the vibronic structures in the absorption and emission spectra, which allowed us to make a detailed theoretical study of this material’s basic optical properties. We have shown that the optical transitions in conjugated polymers may be described by the intensity of the zero-phonon line Io, its width 'TAU' and position Eo, as well as by the electronic and vibrational coupling described by the Huang-Rhys factor, S. These parameters are highly influenced by the chain conformational disorder introduced by the temperature and the variation of the conjugation degree. In order to explain the experimental emission spectra we have explicitly considered the vibrational structure of PPV taking into account the theoretical Franc-Condon approximation. We have been able to reproduce these spectra considering three effective vibrational modes with energies at 330, 1164 and 1550 cm-1, which correspond to intense PPV vibrational structures obtained by infrared and Raman absorption spectroscopy. Studying the line shape we found that the electron-phonon coupling of each effective mode, parameterized by the S factor, has different temperature dependence. This work has allowed us to investigate fundamental aspects of the coupling between electronic states and nuclear movement in conjugated polymers that had not yet been studied in detail in the literature.

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