Download or read book Am lioration de l absorption photonique dans les cellules photovolta ques organiques written by Florent Monestier and published by . This book was released on 2008 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: Le rendement de conversion photoélectrique des cellules photovoltaïques organiques est encore trop faible pour envisager leur production à l’échelle industrielle. La solution proposée est l’amélioration du rendement d’absorption des photons dans les couches photoactives. La première partie de ce travail à concerné le développement d’un logiciel de modélisation et d’optimisation des cellules photovoltaïques organiques. Cet outil permet d’optimiser l’ensemble des épaisseurs des couches d’une cellule classique (bicouche ou mélange) ou des cellules plus complexes (cellules tandem). Puis nous avons relié les propriétés optiques des cellules organiques à leurs propriétés électriques en calculant les densités de courant de court circuit. La validation de nos modélisations a ensuite été réalisée par comparaison avec les résultats expérimentaux. Dans la dernière partie de ce travail nous avons abordé l’étude de l’exaltation locale du champ électromagnétique via des effets de plasmons de surface.
Download or read book Absorption Photonique Dans Les Cellules Photovolta ques Organiques written by Florent Monestier and published by Omniscriptum. This book was released on 2011-08 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: Le rendement de conversion photo lectrique des cellules photovolta ques organiques est encore trop faible pour envisager leur production l' chelle industrielle. La solution propos e dans le cadre de ce travail est l'am lioration du rendement d'absorption des photons dans les couches photoactives. La premi re partie de ce travail a concern le d veloppement d'un logiciel d'optimisation des paisseurs des couches des cellules photovolta ques organiques. Puis les propri t s optiques et les propri t s lectriques ont t reli es en calculant les densit s de courant de court circuit. La validation des mod lisations a ensuite t r alis e par comparaison avec les r sultats exp rimentaux sur des cellules compos es d'h t rojonctions bicouches ou de volume et pour diff rents couples donneur-accepteur. Dans la derni re partie de ce travail l' tude de l'exaltation locale du champ lectromagn tique via des effets de plasmons de surface a t abord e. Pour cela, des empilements de couches organiques, contenant des nanoparticules m talliques (or et argent), a t mod lis , r alis et caract ris dans le but d'exalter localement le champ lectromagn tique.
Download or read book Structures photoniques pour le solaire organique written by David Duché and published by . This book was released on 2010 with total page 187 pages. Available in PDF, EPUB and Kindle. Book excerpt: Les matériaux organiques présentent l'avantage de réduire les coûts de production des dispositifs photovoltaïques. Les efficacités de photo-conversion des cellules solaires organiques (CSOs) sont cependant encore faibles et doivent atteindre 10% pour rendre cette technologie commercialement viable. Dans ce contexte, les concepts photoniques semblent bien adaptés afin d'améliorer l'absorption photonique de ces dispositifs en couches minces et, dans le cadre de cette thématique, nous avons étudié l'utilisation de cristaux photoniques membranaires (CPs) afin de confiner la lumière dans les CSOs. L'objectif est de coupler des modes de Bloch, aussi appelés modes de Bloch lents (MBLs), qui possèdent des vitesses de groupe proches de zéro dans la couche active. A l'aide d'une méthode FDTD (Finite Différence Time Demain), une étude théorique qui concerne l'utilisation de CPs en semi-conducteurs organiques ainsi que leur incorporation dans l'empilement d'une CSO a été réalisée. Nous avons montré qu'une augmentation entre 4 et 11% de l'absorption peut être obtenue en fonction du "gap" du matériau utilisé. Un procédé de nanoimpression a ensuite été utilisé afin de structurer directement des couches minces en P3HT :PCBM sous la forme de CPs capables de coupler des MBLs. En accord avec le modèle, les caractérisations optiques ont montré des gains d'absorption significatifs. De plus, les résultats ont prouvé que les propriétés cristallines des matériaux ne sont pas altérées par le procédé.
Download or read book Les nanomat riaux et leurs applications pour l nergie lectrique written by NOËL Didier and published by Lavoisier. This book was released on 2014-01-10 with total page 474 pages. Available in PDF, EPUB and Kindle. Book excerpt: Les nanotechnologies apportent un fort potentiel d’innovation et de rupture dans de nombreux domaines. Leurs applications pour l’énergie en est un champ important, car la synthèse et la structuration des nanomatériaux y ouvrent des voies de progrès notables. Si divers ouvrages décrivent les innovations promises par les nanotechnologies sur des thématiques scientifiques générales ou spécialisées, très peu abordent le chemin qui va des nouvelles propriétés aux applications pour l’énergie électrique et ses usages. Cet ouvrage présente, sur des bases scientifiques solides, les apports des nanotechnologies et plus particulièrement des nanomatériaux aux enjeux de la production d’électricité et de ses usages. Après un panorama des effets physiques qui peuvent être exploités à ces échelles pour améliorer les propriétés des matériaux ou leur fonctionnalité, leur application à la production d’électricité, à son stockage, à ses usages ainsi qu’au traitement de questions environnementales est abordée. Elle conduit à explorer les domaines de l’électrochimie, du photovoltaïque, de la thermoélectricité, des propriétés mécaniques et thermiques des matériaux ou encore des membranes et des surfaces ultrahydrophobes. Chaque chapitre constitue une monographie exhaustive enrichie d’une abondante iconographie et d’une bibliographie très complète. Les meilleurs experts de chaque domaine ont été réunis, faisant de cet ouvrage une référence incontournable. Au confluent de plusieurs disciplines et en prise directe sur un vaste champ d’applications, ce livre s’adresse à un large public : ingénieurs et chercheurs, étudiants des écoles d’ingénieurs ou des universités aux niveaux licence et master.
Download or read book ICREEC 2019 written by Ahmed Belasri and published by Springer Nature. This book was released on 2020-06-10 with total page 659 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book highlights peer reviewed articles from the 1st International Conference on Renewable Energy and Energy Conversion, ICREEC 2019, held at Oran in Algeria. It presents recent advances, brings together researchers and professionals in the area and presents a platform to exchange ideas and establish opportunities for a sustainable future. Topics covered in this proceedings, but not limited to, are photovoltaic systems, bioenergy, laser and plasma technology, fluid and flow for energy, software for energy and impact of energy on the environment.
Download or read book Artificial Intelligence in Society written by OECD and published by OECD Publishing. This book was released on 2019-06-11 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt: The artificial intelligence (AI) landscape has evolved significantly from 1950 when Alan Turing first posed the question of whether machines can think. Today, AI is transforming societies and economies. It promises to generate productivity gains, improve well-being and help address global challenges, such as climate change, resource scarcity and health crises.
Download or read book Livestock Policy Analysis written by International Livestock Research Institute and published by ILRI (aka ILCA and ILRAD). This book was released on 1995-01-01 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: Policy concepts; Identification of policy issues; Production systems, supply and demand; Market, price and trade policies; Marketing and distribution systems; Budget and manpower planning; Land tenure police for the livestock sector; Policy analysis report writing and communication; Livestock production and marketing in alphabeta - a case study.
Download or read book Government at a Glance Southeast Asia 2019 written by OECD and published by OECD Publishing. This book was released on 2019-09-10 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: Government at a Glance Southeast Asia 2019 is the first edition in the Government at a Glance series for the region. It provides the latest available data on public administrations in the 10 ASEAN member countries: Brunei Darussalam, Cambodia, Indonesia, Lao People’s Democratic Republic, Malaysia, Myanmar, the Philippines, Singapore, Thailand and Viet Nam.
Download or read book Organic Solid State Lasers written by Sébastien Forget and published by Springer. This book was released on 2013-07-03 with total page 179 pages. Available in PDF, EPUB and Kindle. Book excerpt: Organic lasers are broadly tunable coherent sources, potentially compact, convenient and manufactured at low-costs. Appeared in the mid 60’s as solid-state alternatives for liquid dye lasers, they recently gained a new dimension after the demonstration of organic semiconductor lasers in the 90's. More recently, new perspectives appeared at the nanoscale, with organic polariton and surface plasmon lasers. After a brief reminder to laser physics, a first chapter exposes what makes organic solid-state organic lasers specific. The laser architectures used in organic lasers are then reviewed, with a state-of-the-art review of the performances of devices with regard to output power, threshold, lifetime, beam quality etc. A survey of the recent trends in the field is given, highlighting the latest developments with a special focus on the challenges remaining for achieving direct electrical pumping of organic semiconductor lasers. A last chapter covers the applications of organic solid-state lasers.
Download or read book OECD Investment Policy Reviews Uruguay written by OECD and published by OECD Publishing. This book was released on 2021-07-12 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt: In July 2020, the Investment Committee recommended to Council to invite Uruguay to become the 50th adherent to the OECD Declaration on International Investment and Multinational Enterprises. This OECD Investment Policy Review of Uruguay documents the progress made in recent years to align investment policies with the national development strategy in pursuit of the Sustainable Development Goals (SDGs).
Download or read book Introduction to Soft Matter written by Ian W. Hamley and published by John Wiley & Sons. This book was released on 2013-03-18 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an introduction to this exciting and relativelynew subject with chapters covering natural and synthetic polymers,colloids, surfactants and liquid crystals highlighting the many andvaried applications of these materials. Written by an expert in thefield, this book will be an essential reference for people workingin both industry and academia and will aid in understanding of thisincreasingly popular topic. Contains a new chapter on biological soft matter Newly edited and updated chapters including updated coverageof recent aspects of polymer science. Contain problems at the end of each chapter to facilitateunderstanding
Download or read book Modern Surface Organometallic Chemistry written by Jean-Marie Basset and published by John Wiley & Sons. This book was released on 2009-07-10 with total page 725 pages. Available in PDF, EPUB and Kindle. Book excerpt: Covering everything from the basics to recent applications, this monograph represents an advanced overview of the field. Edited by internationally acclaimed experts respected throughout the community, the book is clearly divided into sections on fundamental and applied surface organometallic chemistry. Backed by numerous examples from the recent literature, this is a key reference for all chemists.
Download or read book Flexoelectricity in Liquid Crystals written by Agnes Buka and published by World Scientific. This book was released on 2013 with total page 299 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book intends to give a state-of-the-art overview of flexoelectricity, a linear physical coupling between mechanical (orientational) deformations and electric polarization, which is specific to systems with orientational order, such as liquid crystals. Chapters written by experts in the field shed light on theoretical as well as experimental aspects of research carried out since the discovery of flexoelectricity. Besides a common macroscopic (continuum) description the microscopic theory of flexoelectricity is also addressed. Electro-optic effects due to or modified by flexoelectricity as well as various (direct and indirect) measurement methods are discussed. Special emphasis is given to the role of flexoelectricity in pattern-forming instabilities. While the main focus of the book lies in flexoelectricity in nematic liquid crystals, peculiarities of other mesophases (bent-core systems, cholesterics, and smectics) are also reviewed. Flexoelectricity has relevance to biological (living) systems and can also offer possibilities for technical applications. The basics of these two interdisciplinary fields are also summarized.
Download or read book Laser 50 Years Of Discoveries written by Fabien Bretenaker and published by World Scientific. This book was released on 2014-10-27 with total page 185 pages. Available in PDF, EPUB and Kindle. Book excerpt: This unique book provides an overview of the principle and applications of lasers enriched with numerous illustrations.Being over fifty years old, lasers continue to amaze us. Their performance characteristics are constantly reaching new limits, and the scope of their applications continues to expand. Yet, it took years of effort by teams of physicists to transform the fundamental notions of Einstein into the first experimental beam of laser light. And history is still going on as fundamental research is now triggered by its remarkable properties.This book addresses every aspects of laser light, from its fundamental principles to its industrial applications, at a level particularly suited for high school teachers, students, and anybody curious about science and technology.
Download or read book Fluorine Magnetic Resonance Imaging written by Ulrich Flogel and published by CRC Press. This book was released on 2016-10-26 with total page 426 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past decade, fluorine (19F) magnetic resonance imaging (MRI) has garnered significant scientific interest in the biomedical research community owing to the unique properties of fluorinated materials and the 19F nucleus. Fluorine has an intrinsically sensitive nucleus for MRI. There is negligible endogenous 19F in the body and thus there is no background signal. Fluorine-containing compounds are ideal tracer labels for a wide variety of MRI applications. Moreover, the chemical shift and nuclear relaxation rate can be made responsive to physiology via creative molecular design. This book is an interdisciplinary compendium that details cutting-edge science and medical research in the emerging field of 19F MRI. Edited by Ulrich Flögel and Eric Ahrens, two prominent MRI researchers, this book will appeal to investigators involved in MRI, biomedicine, immunology, pharmacology, probe chemistry, and imaging physics.
Download or read book Surface Photovoltage Analysis Of Photoactive Materials written by Thomas Dittrich and published by World Scientific. This book was released on 2020-02-04 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt: Surface photovoltage (SPV) techniques provide information about photoactive materials with respect to charge separation in space. This book aims to share experience in measuring and analyzing SPV signals and addresses researchers and developers interested in learning more about and in applying SPV methods. For this purpose, basics about processes in photoactive materials and principles of SPV measurements are combined with examples from research and development over the last two decades.SPV measurements with Kelvin probes, fixed capacitors, electron beams and photoelectrons are explained. Details are given for continuous, modulated and transient SPV spectroscopy. Simulation principles of SPV signals by random walks are introduced and applied for small systems. Application examples are selected for the characterization of silicon surfaces, gallium arsenide layers, electronic states in colloidal quantum dots, transport phenomena in metal oxides and local charge separation across photocatalytic active crystallites.
Download or read book Jean Baptiste Say and Political Economy written by Jean-Baptiste Say and published by Taylor & Francis. This book was released on 2016-11-10 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt: Jean-Baptiste Say (1767–1832) was one of the first great economists to have laid down the foundations of economic science. Author of the famous Treatise on Political Economy in 1803, which was revised and re-edited on several occasions, he published numerous other works including a voluminous Complete Course in Practical Political Economy in 1828–9. He also taught political economy successively from 1815 until his death in three Parisian establishments: the Athénée, the Conservatory of Arts and Trades, and the Collège de France. The texts in which Say exposes his approach to political economy have not been available in the English language until now except for the fourth edition of the ‘Preliminary Discourse’ which serves as an introduction to the Treatise. This book presents a translation which renders his works accessible to the English speaking world. For the first time, English readers will be able to become directly immersed in Say’s principal texts, where he develops his conception of political economy. Jean-Baptiste Say and Political Economy proposes a translation of a selection of eleven of Say’s texts. The first three are versions of the ‘Preliminary Discourse’ from the Treatise’s editions of 1803, 1814 and 1826 with the variations of the editions of 1817, 1819 and 1841. The following four texts are the opening discourses pronounced at the Conservatory in 1820 and 1828 and the Collège de France in 1831 and 1832. The eighth text is the ‘General Considerations’ which open the Complete Course in Practical Political Economy of 1828, with the variations of the 1840 re-edition. The final three texts are those Say devotes to ‘the progress of political economy’ in what is akin to a history of economic thought. This volume is of great importance to economic historians and people studying Jean-Baptiste Say, as well as those who are interested in economic theory and philosophy and political economy.
