Book Description
Après un rappel de la théorie sousjacente à la spectroscopie RMN haute résolution sur poudres cristallines, nous présentons une analyse qualitative et quantitative du désordre cristallin sur 9 composés différents analysés par spec-troscopie RMN d'échange. Les composés étudiés sont: C(SiMe3)4, Si(SiMe3)4, C(SnMe3)4, Si(SnMe3)4, Ge(SiMe3)4, (Me3Si)3C-C@C-C(SiMe3)3, Si(SiMe3)-SiPh3, I'ester éthylique de tyrosine (TEE) et différentes phases YH2+x. Une grande variété de modes de réorientation moléculaire est observé. Dans une seconde partie, nous étudions la dynamique des systèmes multispins couplés homonucléaires 1/2 et l'information structurale qu'il est possible d'extraire de ces systèmes à l'aide de méthodes RMN bidimensionnelles de corrélation zéro et double quanta. Les systèmes multispins étudiés sont: SiP207 et TiP207 dans leur phase cubique avec une superstructure 3 x 3 x 3 (RMN 31p) et TEE 100% enrichie en 13C. Dans une dernière partie nous étudions l'information struc-turale contenue dans l'analyse de la forme des spectres RMN obtenus après filtration double quanta (DQF) à la condition R2 (rotational resonance) sur des systèmes de spins 1/2 homonucléaires de petite taille en présence d'aniso-tropie de déplacement chimique importante, de couplage dipolaires directs et indirects. Nous illustrons ainsi la faisabilité de l'approche R2DQF pour extraire tous les paramètres d'un système de spins 1/2.
Author: Agnes Buka Publisher: World Scientific ISBN: 1848167997 Category : Science Languages : en Pages : 299
Book Description
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.
Author: Jean-Marie Basset Publisher: Wiley-VCH ISBN: 9783527319725 Category : Science Languages : en Pages : 725
Book Description
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.
Author: Paolo Mele Publisher: ISBN: 9781536160864 Category : Zinc oxide thin films Languages : en Pages : 0
Book Description
Zinc oxide (ZnO) is an n-type semiconductor with versatile applications such as optical devices in ultraviolet region, piezoelectric transducers, transparent electrode for solar cells and gas sensors. This book "ZnO Thin Films: Properties, Performance and Applications" gives a deep insight in the intriguing science of zinc oxide thin films. It is devoted to cover the most recent advances and reviews the state of the art of ZnO thin films applications involving energy harvesting, microelectronics, magnetic devices, photocatalysis, photovoltaics, optics, thermoelectricity, piezoelectricity, electrochemistry, temperature sensing. It serves as a fundamental information source on the techniques and methodologies involved in zinc oxide thin films growth, characterization, post-deposition plasma treatments and device processing. This book will be invaluable to the experts to consolidate their knowledge and provide insight and inspiration to beginners wishing to learn about zinc oxide thin films.
Author: Alain Reinberg Publisher: CRC Press ISBN: Category : Design Languages : en Pages : 268
Book Description
Periodical and predictable changes in biological susceptibility and response to a large variety of chemical agents, including drugs and food, have been documented since the early 1970s. This book provides a survey of clinically-documented research in chronopharmacology.
Author: Dominique Petit Publisher: ISBN: Category : Languages : fr Pages : 251
Book Description
ETUDE EXPERIMENTALE DE DEUX MATERIAUX DONT L'ION MOBILE EST LI**(+); POSSIBILITE DE DESCRIPTION DE LA DYNAMIQUE LOCALE DE LI**(+) EN TERMES DE SAUTS DANS LA MAILLE ELEMENTAIRE RHOMBOEDRIQUE AU-DESSOUS DE 560 K, UNE TRANSITION DE PHASE, QUI N'AFFECTE QUE LE SOUS RESEAU ALCALIN, MENANT A UN REGIME DE CONDUCTIVITE SUPERIONIQUE AU-DESSUS DE 560 K. CALCUL ANALYTIQUE DE L'EVOLUTION DE LA MATRICE DENSITE POUR UN SPIN 3/2 SUBISSANT UNE INTERACTION QUADRIPOLAIRE ET SOUMIS A UN CHAMP RF; DESCRIPTION DE LA RELAXATION NUCLEAIRE DE SPINS>1/2 DANS LE FORMALISME DE SPINS FICTIFS 1/2 CONDUISANT A UNE DESCRIPTION DE L'EVOLUTION TEMPORELLE DE L'AIMANTATION NUCLEAIRE A L'AIDE D'UNE EQUATION CINETIQUE MACROSCOPIQUE; APPLICATION A L'ETUDE DE LA RELAXATION SPIN-SPIN ET SPIN-RESEAU
Author: Jerome V. Moloney Publisher: Springer Science & Business Media ISBN: 9780387985817 Category : Business & Economics Languages : en Pages : 270
Book Description
Mathematical methods play a significant role in the rapidly growing field of nonlinear optical materials. This volume discusses a number of successful or promising contributions. The overall theme of this volume is twofold: (1) the challenges faced in computing and optimizing nonlinear optical material properties; and (2) the exploitation of these properties in important areas of application. These include the design of optical amplifiers and lasers, as well as novel optical switches. Research topics in this volume include how to exploit the magnetooptic effect, how to work with the nonlinear optical response of materials, how to predict laser-induced breakdown in efficient optical devices, and how to handle electron cloud distortion in femtosecond processes.
Author: Stéphane Viel Publisher: ISBN: Category : Languages : en Pages : 159
Book Description
Nuclear Magnetic Resonance (NMR) is one of the most powerful analytical technique in Chemistry, and many NMR methodologies are now available to elucidate molecular structures and dynamics. In this context, Pulsed Gradient Spin Echo (PGSE) and Diffusion Ordered NMR Spectroscopy (DOSY) are two closely related NMR methodologies, based on molecular mobility, which allow molecular diffusion to be encoded into NMR datasets by means of Pulsed Field Gradients (PFG) of magnetic field. In this thesis, PGSE and DOSY are applied to study micelles and micellar phases, chiral molecules, and uncharged mono and polysaccharides. Finally, a new analytical method is proposed in which High Resolution Magic Angle Spinning and chromatographic phases are combined to enhance the resolution of NMR diffusion edited studies of model mixtures.
Author: Jacques Lafontaine Publisher: Springer ISBN: 3319207350 Category : Mathematics Languages : en Pages : 408
Book Description
This book is an introduction to differential manifolds. It gives solid preliminaries for more advanced topics: Riemannian manifolds, differential topology, Lie theory. It presupposes little background: the reader is only expected to master basic differential calculus, and a little point-set topology. The book covers the main topics of differential geometry: manifolds, tangent space, vector fields, differential forms, Lie groups, and a few more sophisticated topics such as de Rham cohomology, degree theory and the Gauss-Bonnet theorem for surfaces. Its ambition is to give solid foundations. In particular, the introduction of “abstract” notions such as manifolds or differential forms is motivated via questions and examples from mathematics or theoretical physics. More than 150 exercises, some of them easy and classical, some others more sophisticated, will help the beginner as well as the more expert reader. Solutions are provided for most of them. The book should be of interest to various readers: undergraduate and graduate students for a first contact to differential manifolds, mathematicians from other fields and physicists who wish to acquire some feeling about this beautiful theory. The original French text Introduction aux variétés différentielles has been a best-seller in its category in France for many years. Jacques Lafontaine was successively assistant Professor at Paris Diderot University and Professor at the University of Montpellier, where he is presently emeritus. His main research interests are Riemannian and pseudo-Riemannian geometry, including some aspects of mathematical relativity. Besides his personal research articles, he was involved in several textbooks and research monographs.
Author: Xavier Helluy
Author: 
Author: Agnes Buka
Author: Jean-Marie Basset
Author: Paolo Mele
Author: Alain Reinberg
Author: Dominique Petit
Author: Jerome V. Moloney
Author: Stéphane Viel
Author: Jacques Lafontaine