Дисертації з теми "Transport/transfert de charge"
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Liu, Chuan. "Charge transport and charge transfer at organic semiconductor heterojunctions." Thesis, University of Cambridge, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.611516.
Повний текст джерелаCompoint, Mylène. "Transport d'ions potassium à travers une membrane cellulaire : étude des propriétés physicochimiques des canaux kcsa par dynamique moléculaire." Besançon, 2004. http://www.theses.fr/2004BESA2038.
Повний текст джерелаThis thesis is devoted to the study of the physicochemical properties of KcsA channels using classical molecular dynamics simulations. The goal is to reach a better knowledge at the atomic scale of the mechanisms which are responsible forthe ion transport in these transmembrane potassium channels. In the first part,available experimental and theoretical data on the protein properties are presented, while new results obtained during this thesis are discussed in the second part. The main results obtained in part II from restrained MD simulations are as follows : 1) a stable closed conformation for the protein is found with the sequence KWKWKK, 2) strong correlated motions between K+ ions and neighbouring water molecules, and between different K/W couples are determined along the selectivity filter, 3) a realistic open structure is obtained which is consistent with the most recent experimental data. The internal M2 helices rae responsible for the gating mechanism, 4) the gating proceeds according to a zipper mechanism implying first the terminal residues at the innermost part of the M2 helices and then propagating towards the bottom of the cavity, 5) a substantial charge transfer between the K+ ions and the surrounding atoms of the channel is determined using a quantum description for the charges. The third part deals with the presentation of various prospects offered by this work, notably the study of water polarization inside the filter and the cavity in the two protein states, and of the K+/Na+ selectivity of the KcsA by the same quantum methods
Benjamin, Daniel. "Thermal transport and photo-induced charge transport in graphene." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/42746.
Повний текст джерелаHerman, Leslie. "Ru(II) under illumination: a study of charge and energy transfer elementary processes." Doctoral thesis, Universite Libre de Bruxelles, 2008. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210399.
Повний текст джерелаL’ensemble de notre travail s’est concentré sur ces deux domaines d’applications. Par l’étude de différents processus de transfert de charges/d’énergie au sein des complexes seuls (processus intramoléculaires) ou en interaction avec un environnement spécifique (processus intermoléculaires), nous avons souhaité mettre en évidence l’intérêt de l’utilisation d’un nouveau ligand plan étendu, le tpac, au sein de complexes du Ru(II). Un tel ligand permet en effet de conférer d’une part une affinité élevée des complexes résultants pour l’ADN, et d’autre part, de par sa nature pontante, de connecter des unités métalliques entre elles au sein d’entités supramoléculaires de taille importante.
Les propriétés photophysiques de quatre complexes basés sur le ligand plan étendu tpac, le [Ru(phen)2tpac]2+ (P) et son homologue dinucléaire le [(phen)2Ru tpac Ru(phen)2]4+ (PP) (à base de ligands ancillaires phen), ainsi que le [Ru(tap)2tpac]2+ (T) et son homologue dinucléaire le [(tap)2Ru tpac Ru(tap)2]4+ (TT) (à base de ligands ancillaires tap), ont été étudiées et comparées entre elles.
L’examen de ces propriétés, d’abord pour les complexes seuls en solution, en parallèle avec celles de complexes dinucléaires contenant un ligand pontant PHEHAT, a permis de mettre en évidence l’importance de la nature du ligand pontant utilisé. Ces résultats ont ainsi révélé qu’un choix judicieux du ligand pontant permet de construire des entités de grande taille capables de transférer l’énergie lumineuse vers un centre (cas du ligand PHEHAT), ou, au contraire, de relier entre elles des entités ne s’influençant pas l’une l’autre d’un point de vue photophysique (cas du ligand tpac).
Les propriétés des complexes du tpac, étudiés cette fois en présence de matériel génétique (mononucléotide GMP, ADN ou polynucléotides synthétiques), se sont révélées très différentes selon que le complexe portait des ligands ancillaires phen (P, PP) ou tap (T, TT). Seuls les complexes à base de tap sont en effet photoréactifs envers les résidus guanine. Nous avons dès lors focalisé cette partie de notre travail sur les deux complexes T et TT. Cette photoréaction, ainsi que le transfert d’électron photoinduit entre ces complexes excités et la guanine, ont pu être mis en évidence par différentes techniques de spectroscopie d’émission tant stationnaire que résolue dans le temps, ainsi que par des mesures d’absorption transitoire dans des échelles de temps de la nano à la femto/picoseconde. L’étude du comportement photophysique des complexes en fonction du pH a en outre révélé de manière très intéressante que, pour des études en présence d’ADN, la protonation des états excités des complexes devait être considérée. Les résultats de cette étude nous ont fourni des pistes quant à l’attribution des processus observés en absorption transitoire.
Le transfert d’électron a également fait l’objet d’une étude par des méthodes théoriques. Ces calculs ab initio ont permis de mettre en évidence une faible influence de l’énergie de réorganisation sur la vitesse de transfert d’électron, qui semble dépendre plus sensiblement de la non-adiabaticité du processus, mais surtout de l’énergie libre de la réaction et d’un éventuel couplage à un transfert de proton.
L’ensemble des résultats obtenus avec les complexes T et TT en présence de matériel génétique, qui, de manière assez inattendue, sont très semblables, indiquent que ces complexes présentent tous deux un grand intérêt pour le développement de nouvelles drogues antitumorales photoactivables.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished
Jaoui, Alexandre. "Charge and Entropy Transport in Dilute metals." Thesis, Sorbonne université, 2019. http://www.theses.fr/2019SORUS151.
Повний текст джерелаThis manuscript focuses on the electronic heat/charge transport dichotomy and the beyond-quantum-limit transport properties of dilute metals.In the first part, we report on a study of two semi-metals, WP2 and Sb. In both cases, we found that the Wiedemann-Franz (WF) law is recovered at low temperature (T ≈ 2 K), but not at T ≈ 15 K. We show that the finite-temperature deviation from the WF law is due to a mismatch between the prefactors of the T 2-resistivities. In the Boltzmann picture of transport, this difference is associated with abundant small-angle scattering among electrons. However, we argue that momentum-conserving fermionic collisions in normal-state liquid 3He also produce a thermal T2-resistivity. This opens the door for an alternative interpretation : the existence of a hydrodynamic regime of electrons in these semi-metals. In this scenario, the larger T2 thermal resistivity is due to momentum-conserving electronic collisions. In the case of Sb, the ratio of the two T2-prefactors evolves with sample size. This observation supports the hydrodynamic scenario. Finally, we find a large hydrodynamic correction in the phononic thermal conductivity. The second part deals with the fate of the Fermi sea in the quantum limit (QL). In the doped semi-conductor InAs, we observe a field-induced insulating state for all geometries of transport. The comparison with the succession of field-induced states in graphite up to B = 90 T reveals that the ground state of a 3D electron gas beyond the QL is system-dependent. The observation of a saturating resistivity accompanied by vanishing thermoelectric coefficients in InAs points to the existence of a conductive surface state
Caruge, Jean-Michel. "Etude du transport local de charges dans les couches semi-conductrices désordonnées par spectroscopie à une molécule." Bordeaux 1, 2001. http://www.theses.fr/2001BOR12347.
Повний текст джерелаBeggs, Bruce Cameron. "Optical charge injection into a gallium arsenide acoustic charge transport device." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26681.
Повний текст джерелаApplied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate
Rice, Elisabeth. "Computational modelling of electronic states, charge transfer and charge transport in organic semiconductors." Thesis, Imperial College London, 2017. http://hdl.handle.net/10044/1/59946.
Повний текст джерелаKim, Yee Seul. "Investigation of charge transport/transfer and charge storage at mesoporous TiO2 electrodes in aqueous electrolytes." Thesis, Sorbonne Paris Cité, 2018. http://www.theses.fr/2018USPCC161/document.
Повний текст джерелаBetter understanding of the mechanisms of charge transport/transfer and charge storage in transparent mesoporous semiconductive metal oxide films (either functionalized or not by redox-active chromophores) in aqueous electrolytes is of fundamental importance for the development and optimization of a wide range of safe, eco-compatible and sustainable energy producing or energy storage devices (e.g., dye-sensitized solar cells, batteries, photoelectrocatalytic cells, …). To address this question, mesoporous semiconductive TiO2 films prepared by glancing angle deposition (GLAD-TiO2) were selected for their unique high surface area, well-controlled morphology, high transparency in the visible, and well-defined semiconductivity that can be easily adjusted through an external bias, allowing thus their characterization by real-time spectroelectrochemistry. We first investigated charge transfer/transport at GLAD-ITO and GLAD-TiO2 electrodes functionalized by a redox-active manganese porphyrin that can play both the role of chromophore and catalyst. We demonstrate that the electrochemical response of the modified electrodes, recorded either in the absence or presence of O2 as substrate, is strongly dependent on the mesoporous film conductivity. By using cyclic voltammetry coupled to UV-visible absorption spectroscopy, we were able to recover some key information such as the heterogeneous electron transfer rate between the immobilized redox-active dye and the semiconductive material, and also to rationalize the specific electrochemical behavior obtained at a porphyrin-modified GLAD TiO2 film under catalytic turnover. In parallel, we developed a new functionalization procedure of mesoporous metal oxide films (GLAD-ITO in the present case) by electrografting of in-situ generated aryldiazonium salts, allowing for modified electrodes characterized by both a high surface coverage and a particularly good stability over time under hydrolytic conditions. Also, we investigated charge storage at GLAD-TiO2 electrodes under various aqueous electrolytic conditions. We notably evidenced for the first time that fast, massive, and reversible insertion of protons can occur in amorphous nanostructured TiO2 films immersed in near neutral aqueous buffer, with the proton donor being the weak acid form of the buffer but not water. We also demonstrated that this proton-coupled electron charge storage process can occur over the entire range of pH and for a wide range of organic or inorganic weak acids, but also of multivalent metal ion aquo complexes, as long as the applied potential and pKa of weak acid are properly adjusted
Polvani, Carlomaria. "Ion transport and charge transfer by P-type ATPases." Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=74298.
Повний текст джерелаBenazzi, Naïma. "Contribution à l'étude des propriétés de transport électronique de métaux et d'alliages métalliques à l'état liquide et solide au voisinage du point de fusion." Metz, 1991. http://docnum.univ-lorraine.fr/public/UPV-M/Theses/1991/Benazzi.Naima.SMZ919.pdf.
Повний текст джерелаThis work presents a contribution to the study of the electronic transport properties of metals and metallic alloys in the liquid state. We have measured the electrical resistivities of the systems nickel-antimony and nickel-germanium as a function of temperature and concentration. The interpretation of the experimental results was performed within the framework of the t-matrix formalism and by using the partial hard sphere structure factors. We have determined the absolute thermoelectric power (A. T. P. ) of liquid germanium by applying four different kinds of cells, three of them having been deviced in the course of the this work. Furthermore, we have measured the A. T. P. Of liquid germanium based alloys diluted by gallium. The esperimental results are confirmed by the calculations based on the Ashcroft E. C. P. Potential combined with suitably adjusted parameters. The values deduced from the "first principale" potential of Animalu (S. M. P. ) are systematically smaller in magnitude. The A. T. P. Of solid germanium in the range of the melting point could be determined with an accuracy of 5-10 times better than that quoted in the literature, owing to a special experimental set-up and a technique which permitted to control the progression of the solidification. We have discussed the validity of the Wiedemann-Franz law (W-F) linking the electrical and the thermal conductivities. We have derived the thermal conductivity of several liquid metals and mettalic alloys from both the experimental and the calculated electrical resistivities. We have shown that, excepting may be the noble metals, the corrections of the W-F law give a negligible contribution. We have noted that the concentration dependance as well as the temperature coefficient of the thermal conductivity of aluminium-copper alloys show an anormalous behaviour. This phenomena must be confirmed by measuring the thermal conductivity
Ltaief, Adnen. "Processus de transfert de charges et de transport dans les cellules photovoltaïques organiques à base de composites MEH-PPV : C60." Lyon 1, 2005. http://www.theses.fr/2005LYO10240.
Повний текст джерелаFonari, Alexandr. "Theoretical description of charge-transport and charge-generation parameters in single-component and bimolecular charge-transfer organic semiconductors." Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/54323.
Повний текст джерелаTse, Shing Chi. "Charge transport and injection in amorphous organic electronic materials." HKBU Institutional Repository, 2007. http://repository.hkbu.edu.hk/etd_ra/821.
Повний текст джерелаBrown, William Charles. "Mechanisms of pentachlorophenol induced charge transport in lipid membranes." PDXScholar, 1996. https://pdxscholar.library.pdx.edu/open_access_etds/1257.
Повний текст джерелаSánchez-Carrera, Roel S. "Theoretical characterization of charge transport in organic molecular crystals." Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26579.
Повний текст джерелаCommittee Chair: Brédas, Jean-Luc; Committee Member: Kippelen, Bernard; Committee Member: Marder, Seth; Committee Member: Sherrill, David; Committee Member: Whetten, Robert. Part of the SMARTech Electronic Thesis and Dissertation Collection.
Kenney, James Stevenson. "Modeling heterostructure acoustic charge transport devics for perfomance and manufacturability." Diss., Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/13900.
Повний текст джерелаLin, Fuding. "Charge transport in mix-conducting hetero-ionic junctions of polyacetylene ionomers /." Connect to title online (Scholars' Bank) Connect to title online (ProQuest), 2009. http://hdl.handle.net/1794/10229.
Повний текст джерелаBjorklund, Chad Christopher. "The effects of nucleosome core particle packaging on DNA charge transport." Online access for everyone, 2006. http://www.dissertations.wsu.edu/Dissertations/Fall2006/c_bjorklund_120606.pdf.
Повний текст джерелаTsung, Ka Kin. "Transport and device application of triarylamine-based organic semiconductor." HKBU Institutional Repository, 2009. http://repository.hkbu.edu.hk/etd_ra/1013.
Повний текст джерелаSánchez-Carrera, Roel S. "Theoretical characterization of charge transport in organic molecular crystals." Diss., Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26579.
Повний текст джерелаMiomandre, Fabien. "Étude de processus électrochimiques non réversibles par une méthode à base d'opérateurs." Université Joseph Fourier (Grenoble ; 1971-2015), 1995. http://www.theses.fr/1995GRE10163.
Повний текст джерелаYudiarsah, Efta. "Change transport through molecules structural and dynamical effects /." Ohio : Ohio University, 2008. http://www.ohiolink.edu/etd/view.cgi?ohiou1219343872.
Повний текст джерелаRaghibi, Mohamed. "Etude des processus limitant la puissance au sein des batteries Li-ion." Electronic Thesis or Diss., Université Grenoble Alpes, 2024. http://www.theses.fr/2024GRALI011.
Повний текст джерелаLi-ion batteries have become a necessity in human daily life as the most versatile, efficient and performing energy storage & conversion technology, they power our nomad electronic, cars and buffer the renewable intermittent energy sources. However, improvement of current battery systems is needed to meet the requirements of the transport sector in terms of energy density, safety, and cycle life. Besides the active materials, among the strategies to increase battery autonomy, one consists in optimizing the design parameters of the electrode such as the formulation, loading, microstructure, and porosity. The idea is simply to increase the ratio of active materials (negative and positive electrode thickness) to inactive components (separator, current collector…). However, by doing so, the output power density becomes strongly limited by the charge transport within the composite electrodes, notably at high current densities.In this PhD work, Li-battery capacity is investigated as a function of the current density with respect to electrode design parameters such as porosity, formulation, loading, and microstructure as well as temperature. For this purpose, LiFePO4 (LFP) and LiNi0.8Mn0.1Co0.1O2 (NMC 811) based positive electrodes were formulated at different loadings (from 0.4 to 3.4 mAh.cm-2), compositions (Active material%, Carbon%, PVDF binder %), and calendered to reach different porosities (from 20 to 50 %). The microstructure and specific area of the active materials and the electrodes are fully characterized by SEM, Granulometry and BET. Then, the battery power performance, capacity as a function of discharge current, is fully captured and analyzed using a time-saving methodology which enables the determination of a limiting current density (Jlim) and the extraction of an effective diffusion coefficient (Deff) corresponding to the limiting transport process. In addition, the charge transfer resistance (Rct) as a function of the state of charge (SOC) is also reported by coupling GITT and EIS allowing to capture of the physico-chemical processes at stake during the battery cycling. Afterwards, the correlation between design parameters, the temperature and the effective electrochemical parameters such as Deff, Jlim, and Rct is discussed
Descoins, Nicolas. "Outils de simulation des fours tournants dédiés à la pyrolyse de déchets : modélisation dynamique du couplage transport de la charge-transferts de chaleur-réactions chimiques." Toulouse, INPT, 2003. http://www.theses.fr/2003INPT048H.
Повний текст джерелаChoi, Wing Hong. "Carrier transport characterization and divice applications of amorphous organic semiconductors." HKBU Institutional Repository, 2010. http://repository.hkbu.edu.hk/etd_ra/1093.
Повний текст джерелаEbenhoch, Bernd. "Organic solar cells : novel materials, charge transport and plasmonic studies." Thesis, University of St Andrews, 2015. http://hdl.handle.net/10023/7814.
Повний текст джерелаVu, Thi Thu Nga. "Étude des phénomènes de charges d'espace dans des matériaux de câbles et câbles modèles destinés à des applications au transport d'énergie en Haute Tension Continue (HVDC)." Toulouse 3, 2014. http://thesesups.ups-tlse.fr/2389/.
Повний текст джерелаThis work contributes to the development of polymer-insulated high voltage direct current (HVDC) cables, focusing on the investigation of space charge build-up phenomena and their consequences on electric field distribution within cables and cable joints under thermal gradient. In this study, conduction current measurements were realized on two different materials often used for HVDC cable construction, being cross-linked polyethylene (XLPE) used as cable insulation and an elastomer (EPDM) used in accessories. These data were used to build semi-empirical models of conductivity versus temperature and electric field. These models were incorporated in a commercial simulation tool in order to predict charge density and field distributions in more complex geometries such as cylindrical geometry and insulations association, submitted to various thermal and electrical stresses, in non-stationary conditions. Space charge measurements were carried out on bi-layers of XLPE/EPDM, and on medium voltage (MV) model cables and mini-cables, using the pulsed electro acoustic method. Results obtained on bi-layers as models of joints under various conditions of temperature and field show that the sign of the interfacial charges in the bi-layers depends on temperature and electric field. This makes non-homogeneous field distribution in bi-layers. For cables under thermal gradient, results show a switching in time of the position of field maximum from the inner semi-conductor to the outer semi-conductor due to the electrical conductivity gradient resulting from the thermal gradient along cable radius. Simulation results obtained on bi-layers (sign and density of charges) and within MV cables are consistent with charge density profiles obtained experimentally under various electrical and thermal stresses. Deviations between simulation and measurements are attributed to charge accumulation processes not accounted for in the model, involving notably cross-linking by-products. The effect of cross-linking by-products on the response of insulations is investigated through measurements on mini-cables and through the evaluation of parameters relevant to the accumulation of charges applied to various formulations of samples in plaque form. Substantial distortions of the electric field profile were measured, testifying for the evident propensity of by-products to dissociate under the electric field and/or assist charge injection
Santana, José. "Mesure de charges d'espace dans les câbles de transport de l'énergie électrique." Montpellier 2, 1994. http://www.theses.fr/1994MON20030.
Повний текст джерелаDeng, Chenxing. "L'influence de l'irradiation sur les propriétés structurelles et de transport du graphène." Thesis, Paris 11, 2015. http://www.theses.fr/2015PA112078/document.
Повний текст джерелаGraphene is a single layer of honeycomb patterned carbon atoms. It has attracted much of interest in the past decade due to its excellent electronic, optical, and mechanical properties, etc., and shows broad application prospects in the future. Sometimes the properties of graphene need to be modulated to adapt for specific applications. For example, control of doping level provides a good way to modulate the electrical and magnetic properties of graphene, which is important to the design of graphene-based memory and logic devices. Also, the ability to tune the electrical conductance can be used to fabricate graphene transistor, and the chemical vapor deposition (CVD) method shows the possibility to make the preparation of graphene integrated into semiconductor manufacture processes. Moreover, the sensitivity of graphene to the H2O and O2 molecules when exposed to the air ambient will result in weak spin signal and noise background. Irradiation provides a clean method to modulate the electrical properties of graphene which does not involve chemical treatment. By ion or electron irradiation, the electronic band structure of graphene can be tuned and the lattice structure will be modulated as well. Moreover, the charged impurities and doping arising from irradiation can change the electronic properties of graphene such as electron-phonon scattering, mean free path and carrier density. As reported, graphene oxidization can be induced by exposure to oxygen plasma, and N-Doping of Graphene through thermal annealing in ammonia has been demonstrated. Furthermore, the strain in graphene can also be tailored by irradiation, which also contributes to the modification of transport properties of graphene. In conclusion, irradiation provides an efficient physical method to modulate the structural and transport properties of graphene, which can be applied in the graphene-based memory and logic devices, transistor, and integrated circuits (ICs). In this thesis, Helium ion irradiation was performed on graphene grown on SiO2 substrate by CVD method, and the structural and transport properties were investigated. The charge transfer doping in graphene induced by irradiation results in a modification of these properties, which suggests a convenient method to tailor them. Moreover, electron beam irradiation was performed on graphene grown on SiC substrate. The local progressive amorphization, strain and electron doping contribute to the modification of structural and transport properties in graphene which can be observed
Choi, Taeyoung. "STM studies of charge transfer and transport through metal-molecule complexes on ultrathin insulating films." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1299525515.
Повний текст джерелаGrenier, Daniel. "Les stratégies adoptées par le personnel soignant pour réduire la charge transportée lors d'activités de transfert." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape15/PQDD_0004/MQ31730.pdf.
Повний текст джерелаNasani, Ahmad Muntaser. "Etude des phénomènes électrofluidodynamiques sur les gaz empoussiérés en écoulement turbulent : application au transport pneumatique." Poitiers, 1987. http://www.theses.fr/1987POIT2307.
Повний текст джерелаSibari, Hassane. "Transport classique et quantique dans les hétérojonctions GaAlAs/GaAs : rôle des états d'interface." Montpellier 2, 1992. http://www.theses.fr/1992MON20251.
Повний текст джерелаTucker, Carole Elizabeth. "A spectroscopic study of factors affecting charge transfer at organo-metallic interfaces." Thesis, Queen Mary, University of London, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368911.
Повний текст джерелаSalman, Seyhan. "Theoretical characterization of the charge-transport and electroluminescence properties of pi-conjugated organic materials." Diss., Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/34789.
Повний текст джерелаGali, Sai Manoj. "Modélisation des relations structure / propriétés de transport de charge dans les matériaux pour l'électronique organique." Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0693/document.
Повний текст джерелаWith the advancement of technology, miniaturized electronic devices are progressively integrated into our everyday lives, generating concerns about cost, efficiency and environmental impact of electronic waste. Organic electronics offers a tangible solution paving the way for low-cost, flexible, transparent and environment friendly devices. However, improving the functionalities of organic (opto) electronic devices such as light emitting diodes and photovoltaics still poses technological challenges due to factors like low efficiencies, performance stability, flexibility etc. Although more and more organic materials are being developed to meet these challenges, one of the fundamental concerns still arises from the lack of established protocols that correlate the inherent properties of organic materials like the chemical structure, molecular conformation, supra-molecular arrangement to their resulting charge-transport characteristics.In this context, this thesis addresses the prediction of charge transport properties of organic semiconductors through theoretical and computational studies at the atomistic scale, developed along three main axes :(I) Structure-charge transport relationships of crystalline organic materials and the role of energetic fluctuations in amorphous polymeric organic semiconductors. Kinetic Monte-Carlo (KMC) studies employing the Marcus-Levich-Jortner rate formalism are performed on ten crystalline Group IV phthalocyanine derivatives and trends linking the crystalline arrangement to the anisotropic mobility of electrons and holes are obtained. Subsequently, KMC simulations based on the simpler Marcus formalism are performed on an amorphous semiconducting fluorene-triphenylamine (TFB) copolymer, to highlight the impact of energetic fluctuations on charge transport characteristics. A methodology is proposed to include these fluctuations towards providing a semi-quantitative estimate of charge-carrier mobilities at reduced computational cost.(II) Impact of a mechanical strain on the electronic and charge transport properties of crystalline organic materials. Crystalline rubrene and its polymorphs, as well as BTBT derivatives (well studied high mobility organic materials) are subjected to mechanical strain and their electronic response is analyzed. Employing tools like Molecular Dynamic (MD) simulations and plane wave DFT (PW-DFT) calculations, unusual electro-mechanical coupling between different crystallographic axes is demonstrated, highlighting the role of inherent anisotropy that is present in the organic single crystals which translates in an anisotropy of their electro-mechanical coupling.(III) Protonation-dependent conformation of polyelectrolyte and its role in governing the conductivity of polymeric conducting complexes. Polymeric bis(sulfonyl)imide substituted polystyrenes are currently employed as counter-ions and dopants for conducting poly(3,4-ethylenedioxythiophene) (PEDOT), resulting in PEDOT-polyelectrolyte conducting complexes. Employing MD simulations and DFT calculations, inherent characteristics of the polyelectrolyte like its acid-base behavior, protonation state and conformation, are analyzed in conjunction with available experimental data and the role of these characteristics in modulating the conductivity of resulting PEDOT-polyelectrolyte conducting complexes is highlighted.The above studies, performed on different organic electronic systems, emphasize the importance of inherent characteristics of organic materials in governing the charge transport behavior in these materials. By considering the inherent characteristics of organic electronic materials and systematically incorporating them into simulation models, accuracy of simulation predictions can be greatly improved, thereby serving not only as a tool to design new, stable and high performance organic materials but also for optimizing device performances
Le, Poul Nicolas. "Charge transfer at the high-temperature superconductor/liquid electrolyte interface." Thesis, University of Exeter, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.391279.
Повний текст джерелаNaz-Paris, Olivia. "Etude d'isolants soumis à des champs divergents par une mesure directe des distributions de charges injectées." Paris 6, 2000. http://www.theses.fr/2000PA066350.
Повний текст джерелаDéon, Sébastien. "Transfert d'espèces ioniques dans les membranes de nanofiltration : étude expérimentale et modélisation de la sélectivité." Lorient, 2007. http://www.theses.fr/2007LORIS098.
Повний текст джерелаThe aim of this work was to study the separation of charged molecules by nanofiltration. This study is based on the understanding of the various transport phenomena governing the ions rejection by a charged membrane. For this purpose, a knowledge model was developed including a bi-dimensional description of the transport within the polarization layer, the membrane / solution interface partitioning and the pore transport. An experimental study of various salts rejections was also performed with an AFC 40 membrane (PCI). Estimation of the various parameters and validation of the model were carried out from experiments on various single salt solutions. Behaviour of binary solutions was thus investigated to understand the interactions between the physical mechanisms governing the selectivity between mono- and divalent ions. Finally, a critical review of the physical approach was proposed to introduce potential improvements
Hoang, Mai Quyen. "Implémentation de la polarisation dans un modèle de transport de charges appliqué au PEN sous contrainte électrique." Toulouse 3, 2014. http://thesesups.ups-tlse.fr/2631/.
Повний текст джерелаA 1D bipolar model, able to describe transport, trapping and recombination of electronic carriers (electrons and holes) on the basis of experimental results, has been developed. This model already gives good results on low density polyethylene. However improvements are still possible, especially in order to predict any dielectric behavior under electrical stress, particularly polar ones. This work aims at implementing the polarization processes in the charge transport model for polyethylene naphtalene (PEN), a polar polymer, and to define an optimized set of parameters for the model in order to predict the material behavior under any thermo-electrical stress. Thermo-stimulated depolarization current (TSDC), space charge (PEA) measurements, and dielectric spectroscopy (DS) were used to characterize the electrical, dielectric and physic-chemical properties of the material under electric field and temperature, in order to have access to processes related to dipoles and conduction. Four relaxation peaks were observed in the increasing order of temperature. The first three peaks, beta, beta* and alpha, observed using DS and TSDC, are related to the orientation polarization process. The last peak rho, only observed by TSDC, has been attributed to negative charges trapped in the dielectric, and measured with space charge measurement. Polarization phenomena have then been implemented in the charge transport model based on dielectric spectroscopy measurements. The dielectric response has been treated using a Cole-Cole function for each relaxation process, function of the temperature. Then, with the help of an inverse transform Fourier, the time dependent permittivity has been obtained and is added to a charge transport model. Simulated currents are then compared to measured currents under low fields. Experimental and simulated currents are in good agreement when the material response is essentially from dipolar origin. Finally, the developed model was used for experimental protocols where polarization and conduction are present (high fields and/or high temperatures). The first simulations yield to encouraging results regarding the simulated and measured currents, which are comparable
Pratuangdejkul, Jaturong. "Modélisation moléculaire de la sérotonine et de son transporteur." Paris 5, 2005. http://www.theses.fr/2005PA05P634.
Повний текст джерелаThe object of this thesis was initially to establish the three dimensions quantitative structure-activity relationships (3D-QSAR) of 121 chemical compounds in order to determine the necessary physicochemical properties of these molecules transported through SERT. From this study we extracted a pharmacophore for the 3D definition of compound transported by SERT. We have based this study on an exhaustive conformational analysis of serotonin by quantum chemistry. We could show that the electrostatic forces which influence the conformation of serotonin are mainly due to cation-p interactions with a predominant participation of a charge transfer. We also showed that these non-bonded forces influence the two pKa of serotonin that correspond to the ionization of the ammonium and 5-hydroxyl groups. We could predict both pKa's in agreement with the experimental values by using ab initio calculations
Edel, Sandrine. "Modélisation du transport des photons et des électrons dans l'ADN plasmide." Toulouse 3, 2006. http://www.theses.fr/2006TOU30085.
Повний текст джерелаWe present here the last developments of the CPA100 code. The code is aimed at simulating by Monte Carlo the cascade of events intervening in the modeling of photons and electrons transport in cellular medium. Compared to the preceding works, the target is new: it acts of plasmid DNA. Our first problem relates to the optimization of all the physical stage of the primary interaction of particles with the plasmid, which number of atoms amounts per thousands. We thus present in this work new calculation methods, in particular for particles path sampling in nonhomogeneous mediums. The question of algorithmic optimization returns besides like a leitmotiv in all the stages of simulation, until the chemical phase. Parallel to this technical problem, we sought to introduce new molecular cross sections for the electrons. All electrons interactions are managed from a molecular point of view. For ionization cross sections by electron impact, the Binary–Encounter–Bethe model of Kim and Rudd is used. We also present new elastic and excitation cross sections for DNA molecules. To validate a computer code, it is important to compare simulations results with experimental ones. Two major experiments have been modelled. The first relies on the influence of photons energy on DNA damages. The second relates to DNA breakage following iodine 125 decay
Miranti, Rany [Verfasser], Jürgen [Akademischer Betreuer] Parisi, Michael [Akademischer Betreuer] Wark, and Holger [Akademischer Betreuer] Borchert. "Charge transport and transfer processes in CuInS2 nanocrystal-based hybrid solar cells / Rany Miranti. Betreuer: Jürgen Parisi ; Michael Wark ; Holger Borchert." Oldenburg : BIS der Universität Oldenburg, 2015. http://d-nb.info/1081215402/34.
Повний текст джерелаMiranti, Rany Verfasser], Jürgen [Akademischer Betreuer] Parisi, Michael [Akademischer Betreuer] [Wark, and Holger [Akademischer Betreuer] Borchert. "Charge transport and transfer processes in CuInS2 nanocrystal-based hybrid solar cells / Rany Miranti. Betreuer: Jürgen Parisi ; Michael Wark ; Holger Borchert." Oldenburg : BIS der Universität Oldenburg, 2015. http://nbn-resolving.de/urn:nbn:de:gbv:715-oops-26622.
Повний текст джерелаFerlauto, Laura. "Correlation between structural and electrical properties of organic semiconducting materials." Thesis, Strasbourg, 2015. http://www.theses.fr/2015STRAF009/document.
Повний текст джерелаThis thesis presents multiple characterization techniques applied to various organic materials with the ultimate goal of unraveling their structure-properties relationship once encapsulated as active materials in OFETs devices. Particular care is then dedicated to the structural characterization methods (2D-GIXRD, XRR and XRD) both from classical laboratory source and from synchrotron radiation. Various organic materials, comprising p- and n-type small molecules and polymers deposited from solution or by vacuum sublimation are investigated. In particular, the study on OFETs based two functionalized perylene isomers differing only in the shape of the alkyl side-chians demonstrates how the branched and asymmetric nature of the chains can lead to an improvement of the electrical performance with a simple post-deposition thermal treatment, while the fabrication of ambipolar polymeric devices by means of Langmir-Schaefer technique highligts the importance of the deposition method on the arrangement of the material on the substrate surface. A more unusual approach, named in-situ and real-time structural investigation, is also presented to evaluate structural modifications in organic thin films undergoing a particular process. Specifically, the structural responce of pentacene thin films to the application of VSG and VSD to the OFET and of TTF derivatives thin films to the variation of humidty were investigated
Ahme, Helene [Verfasser], and Eicke [Akademischer Betreuer] Weber. "Spectroscopic investigations of transfer and transport of charge carriers in the donor/acceptor network of organic solar cells = Spektroskopische Untersuchungen zum Ladungstransfer und -transport in Donator/Akzeptor Netzwerken von organischen Solarzellen." Freiburg : Universität, 2014. http://d-nb.info/1123480591/34.
Повний текст джерелаIslam, Rakibul. "Electrical and thermal transport properties of polymer/carbonaceous nanostructured composites." Thesis, Lille 1, 2016. http://www.theses.fr/2016LIL10131/document.
Повний текст джерелаConducting polymer nanocomposites exhibit for instance interesting thermoelectric properties which make them a promising, inexpensive, clean and efficient solution for heat waste harvesting. This thesis reports on properties of polyaniline (PANI) nanostructured composites as a function of various carbonaceous nano-fillers content such as carbon nanotubes (1-D), and 2-D reduced graphene oxide (RGO). SEM, TEM, X-ray diffraction, and Raman spectroscopy have been employed to investigate their structure and morphology. Electrical and thermal conductivity, Seebeck coefficient, and thermoelectric figure of merit (ZT) have been systematically performed. An important increase of electrical conductivity has been observed with increasing filler fraction whereas thermal conductivity only slightly increases, which enhances ZT of several orders of magnitude. Fillers dimension effect is evidenced, but, whatever this dimension, it is shown that, in contrast with thermal conductivity, electrical conductivity follows a percolation behavior through 2D conduction process. This behavior is also observed in the case of the volumetric heat capacity of PANI/RGO nanohybrids which make them potential candidates as high heat capacitive materials. For the first time their heat storage factor is assessed with a new analytical model proposed in this study. The PANI/RGO samples have also been investigated by Dielectric Spectroscopy at different temperatures. Results evidence an interesting charge trapping phenomenon occurring at the PANI/RGO interface which might find promising applications in supercapacitors or gate memory devices
Ibraikulov, Olzhas. "Bulk heterojunction solar cells based on low band-gap copolymers and soluble fullerene derivatives." Thesis, Strasbourg, 2016. http://www.theses.fr/2016STRAD046/document.
Повний текст джерелаThe chemical structure of organic semiconductors that are utilized in bulk heterojunction photovoltaic cells may strongly influence the final device performances. Thus, better understanding the structure-property relationships still remains a major task towards high efficiency. Within this framework, this thesis reports in-depth material investigations including charge transport, morphology and photovoltaic studies on various novel low band-gap copolymers. First, the impact of alkyl side chains on the opto-electronic and morphological properties has been studied on a series of polymers. Detailed charge transport investigations showed that a planar conjugated polymer backbone leads to a weak dependence of the charge carrier mobility on the carrier concentration. This observation points out that the intra-molecular torsion angle contributes significantly to the electronic energy disorder. Solar cells using another novel copolymer based on pyridal[2,1,3]thiadiazole acceptor unit have been studied in detail next. Despite the almost ideal frontier molecular orbital energy levels, this copolymer did not perform in solar cells as good as expected. A combined investigation of the thin film microstructure and transport properties showed that the polymers self-assemble into a lamellar structure with polymer chains being oriented preferentially “edge-on”, thus hindering the out-of-plane hole transport and leading to poor charge extraction. Finally, the impact of fluorine atoms in fluorinated polymers on the opto-electronic and photovoltaic properties has been investigated. In this case, the presence of both flat-lying and standing lamellae enabled efficient charge transport in all three directions. As a consequence, good charge extraction was possible and allowed us to achieve a maximum power conversion efficiency of 9.8%
Schwartz, Pierre-Olivier. "Oligomères donneur/accepteur nanostructurés et à séparation de charges optimisée pour la conversion photovoltaïque." Phd thesis, Université de Strasbourg, 2013. http://tel.archives-ouvertes.fr/tel-01064229.
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