Download or read book Synth se de nouveaux mat riaux organiques et organo m talliques pour l optique non lin aire du deuxi me ordre written by Cyrille Monnereau and published by . This book was released on 2005 with total page 271 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ce travail a porté sur la synthèse de nouveaux matériaux pour des applications en optique non-linéaire du deuxième ordre. Le premier volet a concerné la synthèse à l'échelle de 10 g et la caractérisation complète d'un polymère d'étude réticulable construit autour d'un chromophore azoïque (DR1). Le mécanisme de réticulation a été caractérisé. L'évolution de son spectre UV-visible après réticulation a pu être rationalisée par une étude théorique. Dans un deuxième volet, un nouveau polymère réticulable a été développé, intégrant comme chromophore une porphyrine " push-pull " (1.06= 3500.10-30 esu). Une voie de synthèse efficace du polymère a été mise au point. Ce dernier a pu être déposé sur substrat de verre sous forme de films minces. Le troisième volet a concerné la synthèse de complexes de platines comportant dans sa sphère de coordination un ligand riche et un ligand pauvre en électrons. Plusieurs cibles de ce type ont été synthétisées

Download or read book SYNTHESE ET CARACTERISATION DE NOUVEAUX MATERIAUX ORGANIQUES POUR L OPTIQUE NON LINEAIRE QUADRATIQUE written by CHRISTOPHE.. SERBUTOUIEZ and published by . This book was released on 1992 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: LES TRAVAUX PRESENTES DANS CETTE ETUDE ONT TRAIT A L'ELABORATION DE NOUVELLES MOLECULES HYPERPOLARISABLES ET A LA PREPARATION DE NOUVEAUX MATERIAUX CRISTALLINS PRESENTANT UNE SUSCEPTIBILITE MACROSCOPIQUE IMPORTANTE. DANS UN PREMIER TEMPS L'ETUDE SYSTEMATIQUE PAR LA METHODE EFISHG D'UNE SERIE DE TOLANES ET DE STILBENES A PERMIS DE MONTRER L'INTERET DE CES MOLECULES POUR AMELIORER LE COMPROMIS NON-LINEARITE TRANSPARENCE DES MATERIAUX NON LINEAIRE CRISTALLIN. L'ETUDE DES STILBAZOLIUM-ALCANE-SULFONATES, (ANALOGUE HETEROCYCLIQUE DES STILBENES) A PERMIS DE METTRE EN EVIDENCE DEUX NOUVEAUX MATERIAUX ACTIFS NOTE SPS ET MTSPS. L'ETUDE DE CES COMPOSES A AUSSI PERMIS D'OBTENIR UNE ESTIMATION QUANTITATIVE (AU TRAVERS DE LA MESURE DE L'HYPERPOLARISABILITE) DU POUVOIR ATTRACTEUR NOYAU PYRIDINIUM. LA MISE EN EVIDENCE PAR LA METHODE EFISHG DE L'INTERET QUE PRESENTE LE SYSTEME PSEUDO-CONJUGUE ENONE PAR RAPPORT AUX TRANSMETTEURS D'ELECTRON PI CLASSIQUES A PERMIS D'ENVISAGER LA PREPARATION D'UNE MULTITUDE DE CES DERIVAS. UNE DE CEUX-CI NOTE MBID PRESENTE UNE SUSCEPTIBILITE IMPORTANTE (DETECTEE PAR LE TEST SUR POUDRE DE SECOND HARMONIQUE) ET PRESENTE DES APTITUDES EVIDENTES POUR LA CRISTALLOGENESE. ENFIN NOUS AVONS PU MESURER ET METTRE ENE VIDENCE DES PROPRIETES NON LINEAIRE QUADRATIQUE D'UN RADICAL ORGANIQUE STABLE NPNN CONNU PAR AILLEURS POUR SES PROPRIETES FERROMAGNETIQUES

Download or read book SYNTHESE ET CARACTERISATION DE MATERIAUX HYBRIDES ORGANO MINERAUX POUR L OPTIQUE NON LINEAIRE QUADRATIQUE written by BENEDICTE.. LEBEAU and published by . This book was released on 1995 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt: CE MEMOIRE CONCERNE LA SYNTHESE ET LA CARACTERISATION DE MATRICES HYBRIDES ORGANO-MINERALES, DE TYPE SILOXANE-SILICE, A PROPRIETES OPTIQUES NON LINEAIRES DU SECOND ORDRE. LES MATERIAUX ONT ETE CARACTERISES A DIFFERENTS STADES DE LEUR FORMATION: SOL, XEROGEL ET SOLIDE (APRES TRAITEMENT THERMIQUE). DANS CE BUT, LES TECHNIQUES DE RMN MULTINUCLEAIRE (#2#9SI, #1#7O ET #1#3C), DSC, IRTF ET DIFFUSION DES RAYONS X AUX PETITS ANGLES (DPAX) ONT ETE PRINCIPALEMENT UTILISEES. LES PROPRIETES OPTIQUES DE CES FILMS ONT ETE EVALUEES PAR LA METHODE DE REFLEXIONS TOTALES ATTENUEES (RTA) ET PAR DES MESURES DE GENERATION DE SECONDE HARMONIQUE (GSH). LA PREMIERE PARTIE DE CE TRAVAIL CONCERNE L'ELABORATION ET LA CARACTERISATION DE MATRICES HYBRIDES OBTENUES PAR CO-HYDROLYSE D'UN ALCOXYDE DE SILICIUM TRIFONCTIONNEL (R'-SI(OR)#3), LE N-3 TRIETHOXYSILYLPROPYL 2,4-DINITROPHENYLAMINE (TSDP) ET D'UN ALCOXYDE DE SILICIUM TETRAFONCTIONNEL (SI(OR)#4), LE TETRAMETHOXYSILANE (TMOS). LES FAIBLES COEFFICIENTS NON LINEAIRES DU SECOND ORDRE D#3#3 DES SYSTEMES TSDP/TMOS (10 A 2,5 PM/V) NOUS ONT CONDUIT DANS UNE SECONDE PARTIE A LA SYNTHESE DE MATRICES HYBRIDES CONTENANT UN CHROMOPHORE, LE (DIETHANOL-2)AMINO-4' METHYL-2' NITRO-4 AZOBENZENE (RED 17), A FORTE HYPERPOLARISABILITE QUADRATIQUE (55.10#-#3#0 ESU) ET POUVANT ETRE DOUBLEMENT GREFFE A LA MATRICE HYBRIDE. LE RED 17 A ETE GREFFE SUR UN ALCOXYDE DE SILICIUM SELON DEUX VOIES DE SYNTHESE: VIA UNE LIAISON IONOCOVALENTE (TRIETHOXYSILANE OU METHYLDIETHOXYSILANE) ET VIA UNE LIAISON COVALENTE (3-ISOCYANATOPROPYLTRIETHOXYSILANE). LES MATRICES HYBRIDES SYNTHETISEES PAR CO-HYDROLYSE DES ALCOXYSILANES FONCTIONNALISEES PAR LE RED 17 ET DU TMOS PRESENTENT UN COEFFICIENT OPTIQUE NON LINEAIRE DU SECOND ORDRE DE 78 PM/V

Download or read book A la recherche de mat riaux organiques pour l optique non lin aire written by Damien Prim and published by . This book was released on 1994 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: Les travaux présentés concernent la synthèse de thiophènes, sélénophènes et thiéno3,2-bthiophènes substitués par des groupements donneurs et attracteurs. L'introduction de ces substituants a pour but de créer une délocalisation électronique pouvant induire des effets en optique non linéaire. Une première partie décrit la synthèse de 2,5-diaryl-thiophènes et -sélénophènes. La méthode générale préconisée, utilise la condensation de bêta-aryl-bêta-chloro acroléines, de chalcogénures alcalins et de bromures de benzyles. Une étude comparative entre la synthèse précitée et une autre voie utilisant des méthodes de couplages de type Suzuki et Stille est également réalisée. Les études spectroscopiques UV montrent qu'il existe dans une même série, une relation entre la longueur d'onde d'absorption maximale et les constantes de Hammett des substituants présents ; et un déplacement bathochrome en passant de la série soufrée à la série séléniée. Dans une deuxième partie, une étude en série hétérocyclique condensée a permis de développer trois nouvelles voies de synthèse d'aryl thiéno3,2-bthiophènes, utilisant des réactions d'arylation à l'aide d'organométalliques mais également des cyclisations intramoléculaires évitant ces réactions de couplages. Une étude comparative des différentes approches est présentée

Download or read book Synth se organique caract risation physico chimique cristaux liquides written by Lisa Lamouline and published by Editions Universitaires Europeennes. This book was released on 2014-08-11 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cette etude porte sur la synthese organique et la caracterisation physico-chimique de nouveaux cristaux liquides ferroelectriques concus pour l'optique non lineaire. Ces nouveaux modeles de cristaux liquides ont deja fait l'objet d'une etude de simulation. Le but du projet a long terme est donc de correler les mesures experimentales obtenues avec celles acquises auparavant par la modelisation moleculaire. Les cristaux liquides obtenus dans le cadre de cet ouvrage possedent tous une mesophase smectique C. Les facteurs structuraux permettant cette mesophase sont encore mal compris jusqu'a ce jour. L'influence de petits changements au sein des mesogenes (tel que les longueurs de chaine, les groupements installes sur ceux-ci, etc.) influence grandement la stabilite thermique de cette mesophase comme en temoigne cet ouvrage. Cette mesophase est particulierement interessante, car elle suscite un interet dans le domaine de l'optique non lineaire pour la generation de seconde harmonique. De plus, les mesogenes possedant un centre chiral transforment la mesophase smectique C en smectique C chiral par des contraintes de symetrie."

Download or read book COMPLEXES ORGANOMETALLIQUES ET MATERIAUX ORGANIQUES POUR L OPTIQUE NON LINEAIRE written by RAFIKA.. SAIBI LOUCIF and published by . This book was released on 1992 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: DEPUIS UNE DIZAINE D'ANNEES, L'ETUDE DES MATERIAUX POUR L'OPTIQUE NON LINEAIRE QUADRATIQUE A CONNU UN ESSOR CONSIDERABLE. L'ETUDE ET L'OPTIMISATION DES PROPRIETES MOLECULAIRES CONSTITUENT UNE ETAPE ESSENTIELLE VERS L'ELABORATION DE MATERIAUX EFFICACES. NOUS AVONS ETUDIE UNE NOUVELLE FAMILLE DE DERIVES DU FERROCENE. NOUS AVONS MONTRE POUR LA PREMIERE FOIS QUE LA COMPLEXATION DE CES COMPOSES PAR UN SECOND METAL AUGMENTAIT FORTEMENT L'HYPERPOLARISABILITE QUADRATIQUE RESPONSABLE DE LA GENERATION DU SECOND HARMONIQUE. SUR CERTAINS DE NOS COMPOSES, NOUS AVONS DETERMINE L'HYPERPOLARISABILITE DE SECOND ORDRE EN APPLIQUANT LE MODELE QUANTIQUE A DEUX NIVEAUX ET TROUVE UN ACCORD SATISFAISANT AVEC LES VALEURS EXPERIMENTALES. LES MATERIAUX POLYMERES ONT EGALEMENT SUSCITE NOTRE INTERET. UN SYSTEME PARTICULIER A ATTIRE NOTRE ATTENTION OU LA MATRICE DE POLYMERE EST LE PMMA ET LA MOLECULE ACTIVE EST UN DERIVE DE L'AZOBENZENE, LE DISPERSE RED ONE (DR1) DISSOUS DANS LA MATRICE (POLYMERE DOPE) OU GREFFE A LA CHAINE DU POLYMERE (POLYMERE FONCTIONNALISE). AFIN DE FAIRE DE CES MATERIAUX DES DOUBLEURS DE FREQUENCE, NOUS LES AVONS ORIENTE SOUS CHAMP ELECTRIQUE INTENSE PAR EFFET CORONA. NOUS AVONS ETUDIE L'INFLUENCE DE LA PHOTOISOMERISATION DU DR1 SUR LA GENERATION DE SECOND HARMONIQUE. CETTE ISOMERISATION INDUIT UN DICHROISME ET UNE BIREFRINGENCE DANS LE FILM SI LA LUMIERE EXCITATRICE EST POLARISEE. DE PLUS, L'IRRADIATION PAR DE LUMIERE POLARISEE D'UN FILM PREALABLEMENT ORIENTE INDUIT SA DESORIENTATION. A L'INVERSE, L'IRRADIATION A TEMPERATURE AMBIANTE D'UN FILM NON ORIENTE EN PRESENCE D'UN CHAMP ELECTRIQUE INDUIT SON ORIENTATION. L'ORIGINE DE CES PHENOMENES EST LA REACTION DE PHOTOISOMERISATION EZ QUI INDUIT LA ROTATION DES MOLECULES. LES RENDEMENTS QUANTIQUES DE PHOTOISOMERISATION EZ ET ZE ONT ETE DETERMINES DANS LE PMMA A TEMPERATURE AMBIANTE, ET LES VALEURS SONT AUSSI ELEVEES QU'EN SOLUTION

Download or read book Le Golfe Du Saint Laurent petit Oc an Ou Grand Estuaire written by Canada. Department of Fisheries and Oceans and published by Peches Et Oceans Direction Generale Des Communications = Fisheries and Oceans Communications Dir. This book was released on 1991 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of a workshop, the scientific reviews and the contributed papers presented at the symposium. The document presents a brief historical summary of marine research in the Gulf; reports the discussions, conclusions and recommendations of the different working groups on oceanography (physics, biology, chemistry and sedimentology) and on the fishery (fish and invertebrates); then presents the discussions of each multidisciplinary working group, centered around how the St. Lawrence system may be used as a natural laboratory which will contribute to the solution of major long-term problems of conservation of natural resources and of the quality of the environment.

Download or read book Terra 2008 written by Leslie Rainer and published by Getty Publications. This book was released on 2011-06-14 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt: Earthen architecture constitutes one of the most diverse forms of cultural heritage and one of the most challenging to preserve. It dates from all periods and is found on all continents but is particularly prevalent in Africa, where it has been a building tradition for centuries. Sites range from ancestral cities in Mali to the palaces of Abomey in Benin, from monuments and mosques in Iran and Buddhist temples on the Silk Road to Spanish missions in California. This volume's sixty-four papers address such themes as earthen architecture in Mali, the conservation of living sites, local knowledge systems and intangible aspects, seismic and other natural forces, the conservation and management of archaeological sites, research advances, and training.

Download or read book N Heterocyclic Carbenes written by Silvia Diez-Gonzalez and published by Royal Society of Chemistry. This book was released on 2016-11-04 with total page 637 pages. Available in PDF, EPUB and Kindle. Book excerpt: In less than 20 years N-heterocyclic carbenes (NHCs) have become well-established ancillary ligands for the preparation of transition metal-based catalysts. This is mainly due to the fact that NHCs tend to bind strongly to metal centres, avoiding the need of excess ligand in catalytic reactions. Also, NHC‒metal complexes are often insensitive to air and moisture, and have proven remarkably resistant to oxidation. This book showcases the wide variety of applications of NHCs in different chemistry fields beyond being simple phosphine mimics. This second edition has been updated throughout, and now includes a new chapter on NHC‒main group element complexes. It covers the synthesis of NHC ligands and their corresponding metal complexes, as well as their bonding and stereoelectronic properties and applications in catalysis. This is complemented by related topics such as organocatalysis and biologically active complexes. Written for organic and inorganic chemists, this book is ideal for postgraduates, researchers and industrialists.

Download or read book Phosphorus Compounds written by Maurizio Peruzzini and published by Springer Science & Business Media. This book was released on 2011-06-10 with total page 477 pages. Available in PDF, EPUB and Kindle. Book excerpt: Each chapter of Phosphorus Compounds: Advanced Tools in Catalysis and Material Sciences have been carefully selected by the editors in order to represent a state-of-the-art overview of how phosphorus chemistry can provide solutions in various fields of applications. The editors have assembled an international array of world-renowned scientists and each chapter is written by experts in the fields of synthetic chemistry, homogeneous catalysis, dendrimers, theoretical calculations, materials science, and medicinal chemistry with a special focus on the chemistry of phosphorus compounds. Phosphorus Compounds: Advanced Tools in Catalysis and Material Sciences is of interest to a general readership ranging from advanced university course students to experts in academia and industry.

Download or read book Underground Disposal of Radioactive Wastes written by International Atomic Energy Agency and published by . This book was released on 1981 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Scientific Basis for Nuclear Waste Management XXII Volume 556 written by David J. Wronkiewicz and published by . This book was released on 1999-11-24 with total page 1370 pages. Available in PDF, EPUB and Kindle. Book excerpt: Safe and effective management of nuclear waste provides a broad range of challenges for materials science. Waste processing, waste form and engineered barrier properties, interactions between engineered and geological systems, radiation effects, chemistry and transport of waste species, and long-term predictions of repository performance are just some of the scientific problems facing modern society. This book, the 22nd in a very successful series from MRS, offers an international and inter-disciplinary perspective on the issues, and features developments in both fundamental and applied areas. Topics include: development and characterization of ceramic waste forms; ceramic waste form corrosion; glass waste form processing; glass formulation, properties and structure; glass waste form corrosion; spent nuclear fuel; performance assessment; repository backfill; flow and transport; natural analogues; container corrosion; metal waste form corrosion; radionuclide speciation and solubility; radionuclide sorption; microbial effects; radiation effects; cement waste forms and waste treatment.

Download or read book Dynamic Behavior of Materials Volume 1 written by Bo Song and published by Springer. This book was released on 2015-10-23 with total page 265 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dynamic Behavior of Materials, Volume 1 represents the first of nine volumes of technical papers presented at the Society for Experimental Mechanics SEM 15th International Congress & Exposition on Experimental and Applied Mechanics, held at Costa Mesa, California, June 8-11, 2015. The full set of proceedings also includes volumes on: Challenges in Mechanics of Time Dependent Materials, Advancement of Optical Methods in Experimental Mechanics, Experimental and Applied Mechanics 16th International Symposium on MEMS and Nanotechnology, 5th International Symposium on the Mechanics of Biological Systems and Materials, International Symposium on the Mechanics of Composite and Multi-functional Materials, Fracture, Fatigue, Failure and Damage Evolution; and Residual Stress, Thermomechanics & Infrared Imaging, Hybrid Techniques and Inverse Problems.

Download or read book Clay containing Polymeric Nanocomposites written by L. A. Utracki and published by iSmithers Rapra Publishing. This book was released on 2004 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is Part 1 of a two-part set. Part 2 ISBN is 1859574823

Download or read book Forest Decline and Atmospheric Deposition Effects in the French Mountains written by M. Kaennel and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 474 pages. Available in PDF, EPUB and Kindle. Book excerpt: Forest decline became a matter of public and scientific concern in France in 1983 when conifers in the Vosges mountains were found to exhibit unusual crown deterioration. An impassioned controversy on a supposedly large scale forest health problem was then in full swing in Central Europe. A co-ordinated research programme entitled DEFORPA ("Deperissement des For~ts et Pollution AtmospMrique") was launched in 1984. This programme ran from 1984 to 1991 and a number of projects are still in progress. The Programme was sponsored by three French ministries (Enviroument, Agriculture and Forestry, Research and Technologyl), several state agencies, various regional authorities and the Commission of the European Communities (DO xn and DG VI). Initially, emphasis was solely laid on the understanding of forest decline in the mountainous areas - because damage was most obvious there - in relation to natural and man-made factors. Air pollution was given high but not overwhelming priority. Thus, the DEFORPA Programme was not in its essence a nation-wide assessment of air pollution effects, unlike a number of national acidification research programmes in Europe and North America. During. the programme, however, the areas of concern expanded. In particular, research into water acidification in the Vosges mountains was developed in parallel with the DEFORPA Programme, and possible eutrophication of the ground flora in northeastern France became the subject of new research.

Download or read book Air conditioning and Refrigeration Equipment written by and published by . This book was released on 1988 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Scientific Basis for Nuclear Waste Management XXIII Volume 608 written by Robert W. Smith and published by . This book was released on 2000-10-09 with total page 800 pages. Available in PDF, EPUB and Kindle. Book excerpt: This long-standing symposia series has become the premier, international forum for scientific and engineering issues related to all levels and types of radioactive wastes and their management. Topics include: fuel cladding and spent nuclear fuel; container fabrication and corrosion; performance assessment; repository performance; radionuclide sorption and transport; cement-based materials and waste containment; corrosion of ceramic wasteforms; structure and characterization of ceramics; radiation effects; natural analogs; wasteform characterization and processing; and corrosion and characterization of glass wasteforms.