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 SYNTHESE ET ETUDES PHYSICO CHIMIQUES DE CRISTAUX LIQUIDES METALLOORGANIQUES written by Philippe Berdagué and published by . This book was released on 1992 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: LE TRAVAIL PRESENTE TRAITE DE LA SYNTHESE ET DE L'ETUDE PHYSICO-CHIMIQUE DE DOUZE SERIES DE COMPLEXES METALLOORGANIQUES A PROPRIETE CRISTAL-LIQUIDE. UNE ATTENTION TOUTE PARTICULIERE EST DEVOLUE AUX EFFETS, SUR LES PROPRIETES MESOMORPHES, DE DIFFERENTES SUBSTITUTIONS SUR LES LIGANDS. L'EVOLUTION DES TEMPERATURES DE TRANSITION ET DU TYPE DE PHASE OBTENU EN FONCTION DE LA NATURE, DE LA LONGUEUR ET DE LA POSITION DES SUBSTITUANTS EST ANALYSEE EN DETAIL, AUSSI BIEN POUR LES LIGANDS QUE POUR LES COMPLEXES. LES RESULTATS OBTENUS SUR DEUX CENT CINQUANTE PRODUITS MESOGENES DONT UNE CENTAINE DE METALLO-MESOGENES (AVEC ESSENTIELLEMENT LE CUIVRE POUR METAL) CONDUIT A L'EXPRESSION DE LOIS EMPIRIQUES PERMETTANT DE CHOISIR LE TYPE DE SUBSTITUTION LATERALE NECESSAIRE POUR OBTENIR UN NEMATIQUE OU UN SMECTIQUE
Download or read book SYNTHESE DE CRISTAUX LIQUIDES A CHIRALITE AXIALE written by Philippe Hugelé and published by . This book was released on 1997 with total page 235 pages. Available in PDF, EPUB and Kindle. Book excerpt: NOUS AVONS DEMONTRE POUR LA PREMIERE FOIS QUE DES MOLECULES ENANTIOMERIQUEMENT PURES A CHIRALITE AXIALE DONT LE COEUR EST CONSTITUE D'UN BIPHENYL TETRA-ORTHO-SUBSTITUE BLOQUE PAR UN PONT DANS UNE CONFORMATION CHIRALE CONDUISENT A DES PROPRIETES MESOMORPHES : LES DIHYDROOXEPINES INDUISENT UNE MESOPHASE CHOLESTERIQUE TANDIS QUE LA DIHYDROTHIEPINE ET SA SULFONE UNE PHASE CHOLESTERIQUE ET UNE PHASE SMECTIQUE C#*. PAR CONTRE, LES COMPOSES SYNTHETISES CONSTITUES D'UN BIPHENYL TETRA-ORTHO-SUBSTITUE NON PONTE NE PRESENTENT AUCUNE PROPRIETE MESOMORPHE, MEME LORSQUE DES LIASONS HYDROGENES SUPRAMOLECULAIRES SONT POSSIBLES, EN RAISON DE L'ANGLE DIEDRE PROCHE DE 90. L'OBTENTION DES BIPHENYLS TETRA-ORTHO-SUBSTITUES ET ENANTIOMERIQUEMENT PURS REPOSE SUR DEUX NOUVELLES METHODES DE SEPARATION DE BIPHENYLS DIASTEREOMETRES : L'UNE SUR COLONNE DE SILICE ET L'AUTRE PAR DIFFERENCE DE SOLUBILITE DE DIASTEREOMERES DANS LES SOLVANTS ORGANIQUES.
Download or read book Compos s m sog nes cha nes fluor es written by Philippe Kromm and published by . This book was released on 1995 with total page 209 pages. Available in PDF, EPUB and Kindle. Book excerpt: A LA SUITE DE QUELQUES RAPPELS SUR LES CRISTAUX LIQUIDES, LE CHOIX DES MATERIAUX (MESOGENES A CHAINES PERFLUOREE OU SEMI-PERFLUOREE) ET LEUR SYNTHESE SONT DECRITS DE FACON DETAILLEE. LA CARACTERISATION PHYSICO-CHIMIQUE (MICROSCOPIE OPTIQUE, AED ET DIFFRACTION DES RAYONS X) DE CES COMPOSES REVELE LA PRESENCE EXCLUSIVE DE MESOPHASES LAMELLAIRES. L'EVOLUTION DES TEMPERATURES ET ENTHALPIES DE TRANSITION ENTRE LES DIFFERENTES PHASES EST DISCUTEE EN FONCTION DE LA LONGUEUR DES CHAINES ET NOMBRE D'ATOMES DE FLUOR QU'ELLES PORTENT. UNE PHASE S#A DONT L'EPAISSEUR DES COUCHES EST TRES INFERIEURE A LA LONGUEUR MOLECULAIRE A ETE MIS EN EVIDENCE DANS LE CAS DES COMPOSES POLYPHILIQUES. LES STRUCTURES CRISTALLINES DE HUIT DE CES COMPOSES A CHAINE SEMI OU TOTALEMENT PERFLUOREE ONT ETE DETERMINEES AFIN D'EXPLICITER L'ORGANISATION MOLECULAIRE DANS LA MESOPHASE. CETTE ETUDE MONTRE UNE BONNE CORRELATION ENTRE CES PHASES CRISTALLINES ET LES MESOPHASES ATTENDUES (ARRANGEMENT LAMELLAIRE DE MOLECULES ANTIPARALLELES) ET REVELE DES MOLECULES PRESENTANT UNE TRES FORTE INCLINAISON PAR RAPPORT A LA NORMALE AUX COUCHES (L'EPAISSEUR EST DE CE FAIT TRES INFERIEURE A LA LONGUEUR MOLECULAIRE), CE QUI PERMET DE PROPOSER UN MODELE STRUCTURAL POUR LES MESOPHASES SMECTIQUES A ET C DANS LE CAS DES POLYPHILES
Download or read book Synth se de nouveaux oligom res poss dant un ou plusieurs motifs diaziniques applications en tant que cristaux liquides et mat riaux fluorescents written by Sylvain Achelle and published by . This book was released on 2007 with total page 351 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ce travail décrit la synthèse de nouveaux matériaux organiques incorporant des motifs diaziniques. Dans une première partie, nous décrirons la synthèse d'une nouvelle famille d'oligomères linéaires possédant un motif central trifluorométhylpyridazinique. Quand ceux-ci sont substitués par de longues chaînes alkoxy, ces oligomères sont des cristaux liquides. Dans une seconde partie nous décrirons les synthèses d'oligomères linéaires possédant un ou plusieurs motifs éthynylpyridaziniques avec des propriétés fluorescentes et mésogènes intéressantes. Dans une troisième partie, nous présenterons les synthèses d'enchaînements π-conjugués en V ou en étoile avec un coeur pyrimidinique. Cette famille de molécules présente une fluorescence dans le bleu très intense et certaines molécules présentent une importante fluorosolvatochromie positive.
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 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 Mappae Clavicula written by Thomas Phillipps and published by . This book was released on 1847 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 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 Encapsulations written by Alexandru Grumezescu and published by Academic Press. This book was released on 2016-05-27 with total page 926 pages. Available in PDF, EPUB and Kindle. Book excerpt: Encapsulations, a volume in the Nanotechnology in the Agri-Food Industry series,presents key elements in establishing food quality through the improvement of food flavor and aroma. The major benefits of nanoencapsulation for food ingredients include improvement in bioavailability of flavor and aroma ingredients, improvement in solubility of poor water-soluble ingredients, higher ingredient retention during production process, higher activity levels of encapsulated ingredients, improved shelf life, and controlled release of flavor and aroma. This volume discusses main nanoencapsulation processes such as spray drying, melt injection, extrusion, coacervation, and emulsification. The materials used in nanoencapsulation include lipids, proteins, carbohydrates, cellulose, gums, and food grade polymers. Applications and benefits of nanoencapsulation such as controlled release, protections, and taste masking will be explained in detail. Includes the most up-to-date information on nanoencapsulation and nanocontainer-based delivery of antimicrobials Presents nanomaterials for innovation based on scientific advancements in the field Provides control release strategies to enhance bioactivity, including methods and techniques for research and innovation Provides useful tools to improve the delivery of bioactive molecules and living cells into foods
Download or read book Cyclodextrins and Their Complexes written by Helena Dodziuk and published by John Wiley & Sons. This book was released on 2006-08-21 with total page 507 pages. Available in PDF, EPUB and Kindle. Book excerpt: Offering comprehensive and up-to-date know-how in one compact book, an experienced editor and top authors cover every aspect of these important molecules from molecular recognition to cyclodextrins as enzyme models. Chapters include reactivity and chemistry, chromatography, X-ray, NMR plus other physicochemical methods, as well as model calculations, rotaxane and catenane structures, and applications in the pharmaceutical industry. The book also discusses other applications such as in the cosmetics, toiletries, textile and wrapping industries, agrochemistry, electrochemical sensors, and devices. A must for everyone working with these substances.
Download or read book In Situ Gelling Polymers written by Xian Jun Loh and published by Springer. This book was released on 2014-10-01 with total page 229 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the research involving in situ gelling polymers and can be used as a guidebook for academics, industrialists and postgraduates interested in this area. This work summaries the academic contributions from the top authorities in the field and explore the fundamental principles of in situ gelling polymeric networks, along with examples of their major applications. This book aims to provide an up-to-date resource of in situ gelling polymer research.
Download or read book The Journal of the Iron and Steel Institute written by Iron and Steel Institute and published by . This book was released on 1920 with total page 880 pages. Available in PDF, EPUB and Kindle. Book excerpt: Includes sect. "A survey of literature on the manufacture and properties of iron and steel, and kindred subjects" (title varies)
Download or read book Wood Adhesives written by Antonio Pizzi and published by CRC Press. This book was released on 2011-01-07 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wood adhesives are of tremendous industrial importance, as more than two-thirds of wood products in the world today are completely or partially bonded together using a variety of adhesives. Adhesive bonding offers many advantages over other joining methods for wood components, and there has been a great deal of R& D activity in devising new wood adhesives or improving the existing ones. The modern mantra in all industrial sectors is: "think green, go green," which has attracted much attention in the wood adhesive industry. Therefore, there is also a lot of research activity in synthesizing environmentally benign and human-friendly wood adhesives. This book is divided into four parts: Part 1: Fundamental Adhesion Aspects in Wood Bonding; Part 2: Synthetic Adhesives; Part 3: Environment-friendly adhesives; and Part 4: Wood Welding and General Paper. It addresses many different types of wood adhesives, as well as bonding (welding) of wood components without adhesives, a more recent development. The information contained in this book is valuable for individuals engaged in all aspects of wood adhesion and adhesives and, hopefully, will inspire new ideas in wood adhesives, a topic of vital industrial importance.
Download or read book The Atlas of Spectral Data of Sesquiterpene Hydrocarbons written by Daniel Joulain and published by . This book was released on 1998 with total page 658 pages. Available in PDF, EPUB and Kindle. Book excerpt:
