Download or read book ETUDE PAR DIFFUSION RAMAN DES MOUVEMENTS DE ROTATION DANS LES PHASES LIQUIDES ET PLASTIQUES DE COMPOSES FLUORES XF written by M.. GILBERT and published by . This book was released on 1977 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ETUDE DES 3 FACTEURS INFLUENCANT LA FORME DE RAIE RAMAN: LES MOUVEMENTS DE ROTATION DOMINANT SOUVENT JUSQUE DANS LA PHASE PLASTIQUE, L'INTERACTION DIPOLAIRE DE TRANSITION QUI PERTURBE LES RAIES FORTEMENT ACTIVES EN IR ET QUI PROVOQUE L'ESSENTIEL DE LA RELAXATION DE VIBRATION, LE COUPLAGE DE CORIOLIS QUI MODIFIE LE PROFIL DE CERTAINES RAIES CAPABLES DE FOURNIR DES RENSEIGNEMENTS SUR LES ROTATIONS.

Download or read book PHENOMENES DE RELAXATION DANS LA DYNAMIQUE DES FLUIDES SIMPLES DANS LA REGION DES THZ ETUDIES PAR LA DIFFUSION INELASTIQUE DES RAYON X written by ALESSANDRO.. CUNSOLO and published by . This book was released on 1999 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt: LA DYNAMIQUE A L'ECHELLE ATOMIQUE DE DIFFERENTS EXEMPLES DE FLUIDES SIMPLES A ETE ETUDIEE DANS LE DOMAINE DE TRES HAUTES FREQUENCES (THZ) EN UTILISANT LA TECHNIQUE DE LA DIFFUSION INELASTIQUE DES RAYONS X AVEC UNE RESOLUTION DE L'ORDRE DU MEV. L'ETUDE EXPERIMENTALE EST STRUCTUREE NATURELLEMENT EN TROIS PARTIES. DANS LA PREMIERE, LE CAS DE LA DYNAMIQUE DES FLUIDES SIMPLES EST TRAITE, AVEC POUR EXEMPLE, LE NEON TRES AU DELA DU POINT CRITIQUE. DANS CE CAS, LE DYNAMIQUE ATTENDUE DOIT ETRE PROCHE DE CELLE DU CAS SIMPLE DES FLUIDES A SPHERES DURES, OU LES INTERACTIONS CONSISTENT EN COLLISIONS MUTUELLES ENTRE PARTICULES. LA DEUXIEME PARTIE CONCERNE L'ETUDE DE LA DYNAMIQUE DE SYSTEMES PLUS COMPLEXES, ELLE EST ILLUSTREE PAR L'EXEMPLE DU NEON CETTE FOIS EN PHASE LIQUIDE. L'OBJECTIF DE CETTE ANALYSE EST DE DIFFERENCIER LES EFFETS LIES AUX INTERACTION A PLUSIEURS CORPS TYPIQUES DES LIQUIDES, PAR RAPPORT A L'ETAT SUPERCRITIQUE. DANS LA DERNIERE PARTIE, NOUS ABORDONS L'ETUDE DE LA DYNAMIQUE DES LIQUIDES POUR LESQUELS EXISTENT DES INTERACTIONS SPATIALES A LONGUE DISTANCE ENTRE MOLECULES. LE LIQUIDE CHOISIT EST L'EAU EN PHASE LIQUIDE. POUR CES TROIS ETUDES, UN INTERET PARTICULIER A ETE ACCORDE A LA CARACTERISATION DES PHENOMENES DE RELAXATION. PLUS SPECIFIQUEMENT, NOUS MONTRONS COMMENT LES PHENOMENES DE RELAXATION EVOLUENT AVEC LE DEGRE DE CONNECTIVITE CROISSANT DES SYSTEMES. NOUS NOUS INTERESSONS A DEUX LARGES CLASSES DE PHENOMENES DE RELAXATION : MICROSCOPIQUES ET STRUCTURALES. LES RELAXATIONS STRUCTURALES SONT LIEES A DES PROCESSUS COOPERATIFS PAR LESQUELS LA STRUCTURE LOCALE, APRES AVOIR ETE PERTURBEE PAR UNE FLUCTUATION SPONTANEE DE DENSITE, SE REARRANGE VERS UNE NOUVELLE POSITION D'EQUILIBRE. LES RELAXATIONS MICROSCOPIQUES, D'UN AUTRE COTE, NE SONT PAS COOPERATIVES, ELLES IMPLIQUENT UNE VIBRATION ATOMIQUE AYANT UNE ECHELLE DE TEMPS DE L'ORDRE DE 10 1 3S ET NE DEPENDENT PRATIQUEMENT PAS DE LA TEMPERATURE. LES PREMIERES DOMINENT LES PHENOMENES OBSERVES DANS L'EAU, TANDIS QUE DANS LE CAS DU NEON SUPERCRITIQUE OU LIQUIDE, CE SONT LES RELAXATIONS MICROSCOPIQUES QUI SONT OBSERVEES.

Download or read book Light and Matter Id Licht und Materie Id written by H. Bilz and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 614 pages. Available in PDF, EPUB and Kindle. Book excerpt: The dynamical properties of solids have recently attracted renewed interest in connection with the increasing understanding of phase transitions and re lated phenomena. In particular, soft modes or, more generally, phonon 'anom alies' seem to play an important role in structural and electronic phase tran sitions, such as ferroelectric or superconducting transitions. The understanding of the mechanisms responsible for the occurrence of unusually low frequencies in phonon spectra requires a detailed analysis of the microscopic forces governing the lattice vibrations. Of particular importance is the influence of the electron lattice interaction in the adiabatic approximation which in many cases is the origin of peculiarities in the phonon self-energy. In this work the vibrational spectra of pure non-metals and of those con taining point defects are investigated. ' In these materials the interrelation be tween the pseudo-harmonic forces (determining the phonon dispersion re lations) and the non-linear anharmonic and electron-phonon forces (as they act in infrared and Raman spectra) is most obvious and can be quantitatively analysed in terms of appropriate models. The main task is to arrive at a physically correct treatment of electronic degrees of freedom, as for example in an electronic 'shell' model, which leads to the description of phonon spectra in terms of long-range polarizabilities and short-range deformabilities. The pur pose of our review is to stimulate further investigations which, we hope, will result in explicit relations between the parameters of the semi-microscopic models and the matrix elements from the electronic band structure.

Download or read book Mouvements r orientationnels en phases mol culaires condens es written by Françoise Fried and published by . This book was released on 1974 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rappel de la théorie de la réponse linéaire de Kubo, des modèles physiques utilises pour décrire les phases solides réorientationnelles et les liquides moléculaires; critique des méthodes expérimentales d'étude: résonance et relaxation RMN, absorption-dispersion diélectrique, diffusion Raman. Etude de cristaux plastiques par RMN à bande large: dioxanne-1,4, thiophène et 4 cyclanone. Etude plus poussée du furanne en phases plastique et liquide

Download or read book Etude de transitions de phase structurales dans KLiS0 4 written by Kihal Bouziane and published by . This book was released on 1986 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt: Etude par diffusion raman entre la température ambiante et 130k avec utilisation de résultats disponibles sur la diffusion brillouin; confirmation du groupe d'espace p6::(3) à la température ambiante et mise en évidence de la présence vraisemblable de deux phases dans l'intervalle 190-265k. Interprétation satisfaisante des résultats obtenus au dessous de 190k par l'existence de domaines ferroelastiques équivalents par rotation de 2pi /3 autour de l'axe c de la phase hexagonale prototype

Download or read book ETUDE DES EXCITATIONS COLLECTIVES DES 4HE ET 3HE SUPERCRITIQUES EN UTILISANT LA TECHNIQUE DE DIFFUSION INELASTIQUE DE RAYONS X DOTEE D UNE RESOLUTION EN ENERGIE DE L ORDRE DU MEV written by ROBERTO.. VERBENI and published by . This book was released on 1998 with total page 177 pages. Available in PDF, EPUB and Kindle. Book excerpt: LA DYNAMIQUE ATOMIQUE DES #4HE ET #3HE SUPERCRITIQUES A ETE ETUDIEE PAR LA TECHNIQUE DE DIFFUSION INELASTIQUE DE RAYONS X (IXS) AVEC UNE RESOLUTION EN ENERGIE DE L'ORDRE DU MEV. LA REGION THERMODYNAMIQUE ANALYSEE DANS CE TRAVAIL, NON ACCESSIBLE PAR LES AUTRES TECHNIQUES, PERMET D'ETUDIER LES MODES COLLECTIFS AVEC UN TRANSFERT D'IMPULSION Q DE L'ORDRE DE L'INVERSE DE LA DISTANCE INTERATOMIQUE ET DANS UNE LARGE GAMME DES TEMPERATURES ET DENSITES. CETTE ETUDE A MONTRE QUE LES EXCITATIONS COLLECTIVES DES #4HE ET #3HE SUPERCRITIQUES PRESERVENT UNE NATURE DE TYPE ACOUSTIQUE DANS LA REGION DES FAIBLES Q, ALORS QUE EN APPROCHANT LA REGION DE QQ#M (Q#M CORRESPOND AU PREMIER MAXIMUM DU FACTEUR DE STRUCTURE STATIQUE S(Q)), CET ASPECT EST PERDU. LES SPECTRES DES EXCITATIONS, EN EFFET, CHANGENT DE FACON CONTINUE EN PASSANT D'UN TRIPLET BRILLOUIN BIEN DEFINI A FAIBLE Q A UN SEUL PIC TRES PRONONCE A QQ#M. DANS CETTE REGION DES HAUTES FREQUENCES, LES MODES COLLECTIFS SONT TRES INFLUENCES PAR LA STRUCTURE LOCALE ET IL A ETE POSSIBLE D'ETABLIR UNE RELATION ENTRE S(Q) ET L'ENERGIE DE CES EXCITATIONS. DANS LE FLUIDE SUPERCRITIQUE, A L'INVERSE DU LIQUIDE, LA DISPERSION POSITIVE ET LE PROPAGATION GAP N'ONT PAS ETE OBSERVES DANS LA RELATION DE DISPERSION. L'ETUDE EN FONCTION DE LA TEMPERATURE A DENSITE CONSTANTE A MONTRE UNE TRANSITION GRADUELLE D'UN MODE DU TYPE SOLIDE A BASSE TEMPERATURE A UN MODE QUI APPROCHE CELUI D'UN GAZ IDEAL A HAUTE TEMPERATURE. LES SEULES DIFFERENCES OBSERVEES DANS CE TRAVAIL ENTRE LES MODES COLLECTIFS DES #4HE ET #3HE PEUVENT ETRE ATTRIBUEES A LA DIFFERENCE DE MASSE. UNE AUTRE PARTIE DE CETTE THESE A ETE CONSACREE A LA REALISATION ET LA CARACTERISATION DU MONOCHROMATEUR DE LA LIGNE DE LUMIERE BL21 A L'ESRF, ET L'INSTALLATION DE SON CONTROLE EN TEMPERATURE. LA STABILITE OBTENUE (MEILLEURE QUE 1 MK) EST UN DES FACTEURS QUI A PERMIS LA REALISATION, JUSQU'A PRESENT, DES EXPERIENCES AVEC UNE RESOLUTION EN ENERGIE DE 1,5 MEV EN UTILISANT DES PHOTONS DE 21,747 KEV.

Download or read book Complex Inorganic Solids written by Patrice E. A. Turchi and published by Springer Science & Business Media. This book was released on 2007-12-31 with total page 420 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the key aspects of this volume is to cut across the traditional taxonomy of disciplines in the study of alloys. Hence there has been a deliberate attempt to integrate the different approaches taken towards alloys as a class of materials in different fields, ranging from geology to metallurgical engineering. The emphasis of this book is to highlight commonalities between different fields with respect to how alloys are studied. The topics in this book fall into several themes, which suggest a number of different classification schemes. We have chosen a scheme that classifies the papers in the volume into the categories Microstructural Considerations, Ordering, Kinetics and Diffusion, Magnetic Considerations and Elastic Considerations. The book has juxtaposed apparently disparate approaches to similar physical processes, in the hope of revealing a more dynamic character of the processes under consideration. This monograph will invigorate new kinds of discussion and reveal challenges and new avenues to the description and prediction of properties of materials in the solid state and the conditions that produce them.

Download or read book The Radiation Chemistry of Polysaccharides written by International Atomic Energy Agency and published by . This book was released on 2017-05 with total page 467 pages. Available in PDF, EPUB and Kindle. Book excerpt: This publication provides the background and compiles the most recent research findings as well as detailing development activities relating to the development of radiation processed products made of natural polymers. Successes clearly indicate that the radiation processing of natural polymers has emerged as an exciting area where the unique characteristics of these polymeric materials can be exploited for a variety of practical applications in agriculture, healthcare, industry and the environment.

Download or read book Properties of Complex Inorganic Solids written by A. Gonis and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 499 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is common practice today to use the term "alloy" in connection with specific classes of materials, with prominence given to metals and semiconductors. However, there is good justification for considering alloys in a unified manner based on properties rather than types of materials because, after all, to alloy means to mix. The scientific aspects of mixing together different materials has a very long history going back to early attempts to understand and control materials behavior for the service of mankind. The case for using the scientific term "alloy" to mean any material consisting of more than one element can be based on the following two considerations. First, many alloys are mixtures of metallic, semiconducting, and/or insulating materials, and the properties of an alloy, i.e., metallic, semiconducting, or insulating, are often functions of composition and of external conditions, such as temperature and pressure. Second, and most importantly, in attempting to understand the various properties of materials, whether physical, chemical, or mechanical,one is apt to use the terminology and experimental, formal, and computational methods in their study that transcend the type of material being studied.

Download or read book Theory of X Ray Diffraction in Crystals written by William H. Zachariasen and published by Dover Publications. This book was released on 2004 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This classic by one of the great figures in x-ray structure analysis provides a vigorous mathematical treatment of its subject. Addresses such fundamentals as crystal faces and edges, the lattice postulate, lattice rows and panes, as well as point, translation, and space groups. 1945 edition.

Download or read book Handbook of Materials for String Musical Instruments written by Voichita Bucur and published by Springer. This book was released on 2016-08-29 with total page 977 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book addresses core questions about the role of materials in general and of wood in particular in the construction of string instruments used in the modern symphony orchestra – violins, violas, cellos and basses. Further attention is given to materials for classical guitars, harps, harpsichords and pianos. While some of the approaches discussed are traditional, most of them depend upon new scientific approaches to the study of the structure of materials, such as for example wood cell structure, which is visible only using modern high resolution microscopic techniques. Many examples of modern and classical instruments are examined, together with the relevance of classical techniques for the treatment of wood. Composite materials, especially designed for soundboards could be a good substitute for some traditional wood species. The body and soundboard of the instrument are of major importance for their acoustical properties, but the study also examines traditional and new wood species used for items such as bows, the instrument neck, string pegs, etc. Wood species’ properties for musical instruments and growth origins of woods used by great makers such as Antonio Stradivari are examined and compared with more recently grown woods available to current makers. The role of varnish in the appearance and acoustics of the final instrument is also discussed, since it has often been proposed as a ‘secret ingredient’ used by great makers. Aspects related to strings are commented.As well as discussing these subjects, with many illustrations from classical and contemporary instruments, the book gives attention to conservation and restoration of old instruments and the physical results of these techniques. There is also discussion of the current value of old instruments both for modern performances and as works of art having great monetary value.The book will be of interest and value to researchers, advanced students, music historians, and contemporary string instrument makers. Musicians in general, particularly those playing string instruments, will also find its revelations fascinating. It will also attract the attention of those using wood for a variety of other purposes, for its use in musical instruments uncovers many of its fundamental features. Professor Neville H. FletcherAustralian National University, Canberra

Download or read book Magnetoelectric Interaction Phenomena in Crystals written by Manfred Fiebig and published by Springer Science & Business Media. This book was released on 2013-11-09 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the quest for higher data density in information technology manipulation of magnetization by other means than magnetic fields has become an important challenge. This lead to a startling revival of the magnetoelectric effect, which characterizes induction of a polarization by a magnetic field or of a magnetization by an electric field. The magnetoelectric crosslink of material properties opens just those degrees of freedom which are needed for the mutual control of magnetic and electric states. The book gives a state-of-the-art review on magnetoelectrics research, classifies current research tendencies, and points out possible future trends. Novel compounds and growth techniques and new theoretical concepts for the understanding of magnetoelectric coupling phenomena are introduced. Highlights are the discovery of "gigantic" magnetoelectric effects which are strong enough to trigger electric or magnetic phase transitions; the concept of magnetochirality; and development "structural" magnetoelectric effects in artificial multiphase compounds. The book is addressed to condensed-matter physicists with a particular focus on experts in highly correlated systems.

Download or read book From Mantle to Meteorites written by K. Gopalan and published by Oxford University Press, USA. This book was released on 1990 with total page 358 pages. Available in PDF, EPUB and Kindle. Book excerpt: Professor Lai combines a deep understanding of the physics of high energy particle interactions with a rare insight into the evolution of the tenuous trails which they leave behind in naturally occurring chemical systems. Thus, by tracking down the exotic products of these high energy interactions into the specific niches of various low energy chemical reservoirs, he has made pioneering contributions to such diverse fields a astrophysics, planetary evolution, oceanography and archaeology.

Download or read book Collected Reprints written by and published by . This book was released on 1972 with total page 582 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modern Aspects of Small Angle Scattering written by H. Brumberger and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 470 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of the NATO Advanced Study Institute, Como, Italy, May 12--22, 1993

Download or read book The Optical Principles of the Diffraction of X rays written by R. W. James and published by . This book was released on 1967 with total page 664 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Sensors written by Yueh-Min Ray Huang and published by Springer Science & Business Media. This book was released on 2008-07-24 with total page 425 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sensors are the most important component in any system and engineers in any field need to understand the fundamentals of how these components work, how to select them properly and how to integrate them into an overall system. This book has outlined the fundamentals, analytical concepts, modelling and design issues, technical details and practical applications of different types of sensors, electromagnetic, capacitive, ultrasonic, vision, Terahertz, displacement, fibre-optic and so on. The book: addresses the identification, modeling, selection, operation and integration of a wide variety of sensors, demonstrates the concepts of different sensors technology through simulation, design and real implementations, discusses the design and fabrication of high performance modern sensors technology, presents a selection of cutting-edge applications. Written by experts in their area of research, this book will be useful reference book for engineers and scientist especially the post-graduate students find this book as reference book for their research.