Download or read book Etude du comportement acoustique et vibratoire de mat riaux perfor s et poreux written by Pascal Allemon and published by . This book was released on 1997 with total page 390 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ce travail porte sur le comportement acoustique et vibratoire de matériaux poreux et perforés. Dans la 1ère partie, les différents aspects de la modélisation de la propagation des ondes acoustiques dans les milieux poreux, à matrice rigide, saturés d'air, sont énumérées. Ces modèles sont repris pour traiter et caractériser le comportement acoustique de panneaux multicouches absorbants, à parement perforés. Plusieurs types d'associations "Poreux-Tôle perforée" sont considérés pour mettre en évidence le rôle de chaque constituant. Le cas particulier de résonateurs couplés, constitués uniquement d'un assemblage de tôles perforés, est abordé. Ces différents comportements étant rappelés, des matériaux poreux de remplacement originaux, issus du broyage de matériaux recyclés sont utilisés dans la conception de ces panneaux absorbants à parement perforés. Il est montré que ces matériaux granulaires pulvérulents ont des propriétés acoustiques étroitement liées à la classe granulométrique employée et donc à la répartition de la taille des pores. Ils peuvent, parfois, avantageusement substituer les laines minérales habituellement utilisées. La 2nde partie porte sur l'étude des caractéristiques mécaniques et sur le comportement vibratoire de plaques métalliques perforées. Les constantes élastiques de celles-ci sont calculées à partir de celles de la tôle pleine par le biais de la théorie de Meijers. Le comportement vibratoire de ces tôles peut être prévu. Ceci est confirmé par la confrontation avec les résultats d'une expérience simple : la mesure de l'impédance mécanique ponctuelle d'un disque à bord libre excité en son centre, et par l'observation des déformés, pour différents modes de vibration, sur clichés obtenus par interférométrie holographique par double exposition.
Download or read book Etude experimentale de comportement acoustique des materiaux poreux a structure rigide written by Yvan Champoux and published by . This book was released on 1991 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Etude des propri t s acoustiques et comportement l impact de mat riaux poreux de type mousses m talliques homog nes et inhomog nes written by Carlos Javier Sacristán López-Mingo and published by . This book was released on 2015 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ce travail concerne l'étude acoustique théorique et expérimentale des matériaux poreux à squelette métallique, macroscopiquement homogènes et inhomogènes ainsi que l'étude de leurs propriétés mécaniques de comportement au choc pour comparaison. Le modèle acoustique de Johnson -Champoux - Allard s'est montré adapté pour la modélisation acoustique. Ce modèle associé à une approche proposée récemment et utilisant le concept de matrices de transfert en parallèle a permis, dans une nouvelle approche basée sur les "mélanges de matériaux", d'étudier les matériaux poreux macroscopiquement inhomogènes. Par ailleurs, une étude paramétrique du coefficient d'absorption en fonction de la porosité et de la fréquence a été proposée. Les maxima d'absorption ainsi que l'enveloppe des courbes d'absorption en fonction de la porosité ont été étudiés. En premier lieu, un matériau théorique à propriétés indépendantes a été étudié. Les matériaux réels à propriétés interdépendantes ont ensuite été abordés à l'aide d'un modèle reliant leurs propriétés à la porosité. Enfin, une comparaison entre les propriétés acoustiques et les propriétés mécaniques de comportement à l'impact a été initiée en vue de déterminer un critère objectif permettant de proposer un compromis entre les deux domaines.
Download or read book Propagation of Sound in Porous Media written by J.F. Allard and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book has grown out of the research activities of the author in the fields of sound propagation in porous media and modelling of acoustic materials. It is assumed that the reader has a background of advanced calculus, including an introduction to differential equations, complex variables and matrix algebra. A prior exposure to theory of elasticity would be advantageous. Chapters 1-3 deal with sound propagation of plane waves in solids and fluids, and the topics of acoustic impedance and reflection coefficient are given a large emphasis. The topic of flow resistivity is presented in Chapter 2. Chapter 4 deals with sound propagation in porous materials having cylindrical pores. The topics of effective density, and of tortuosity, are presented. The thermal exchanges between the frame and the fluid, and the behaviour of the bulk modulus of the fluid, are described in this simple context. Chapter 5 is concerned with sound propagation in other porous materials, and the recent notions of characteristic dimensions, which describe thermal exchanges and the viscous forces at high frequencies, are introduced. In Chapter 6, the case of porous media having an elastic frame is considered in the context of Biot theory, where new topics described in Chapter 5 have been included.
Download or read book Dictionary of Building and Civil Engineering written by Don Montague and published by Taylor & Francis. This book was released on 1996 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dual-language dictionary lists over 20,000 specialist terms in both French and English, covering architecture, building, engineering and property terms. It meets the needs of all building professionals working on projects overseas. It has been comprehensively researched and compiled to provide an invaluable reference source in an increasingly European marketplace.
Download or read book Acoustic Absorbers and Diffusers written by Trevor J. Cox and published by CRC Press. This book was released on 2009-01-26 with total page 495 pages. Available in PDF, EPUB and Kindle. Book excerpt: Absorbers and diffusers are two of the main design tools for altering the acoustic conditions of rooms, semi-enclosed spaces and the outdoor environment. Their correct use is important for delivering high quality acoustics. Unique and authoritative, this book decribes how to effectively measure, model, design and apply diffusers and absorbers. It is a resource for new and experienced acousticians, seeking an understanding of the evolution, characteristics and application of modern diffusers. Absorption is a more established technology and so the book blends traditional designs with modern developments. The book covers practical and theoretical aspects of absorbers and diffusers and is well illustrated with examples of installations and case studies. This new edition brings Acoustic Absorbers and Diffusers up-to-date with current research, practice and standards. New developments in measurement, materials, theory and practice since the first edition (published in 2004) are included. The sections on absorbers are extended to include more about noise control.
Download or read book Adhesion Between Polymers and Concrete Adh sion Entre Polym res Et B ton written by H. R. Sasse and published by Springer. This book was released on 1986 with total page 792 pages. Available in PDF, EPUB and Kindle. Book excerpt: Preface Adhesion is a phenomenon architects and civil engineers are not very familiar with. In other disciplines knowledge about surface properties and the background of bonding energies is also far from satisfactory; nevertheless there are many important· applications in concrete engineering, where adhesion is necessary for success and durability. These include: - coating and painting - repair of concrete surfaces - bonding of fresh to old concrete - crack injection - glueing of precast elements - glueing of steel to concrete, etc. In 1981 RILEM established the technical committee 52-RAC 'Resin Adherence to Concrete'. The main aims of the committee's work were - to collect research results and practical experiences - to initiate and coordinate research programs - to develop, on a scientific base, test methods for field and for laboratory purposes. One of the results of the committee's work is a state-of-the-art report, which will be presented orally as a General Report at the International Symposium ISAP '86, and will be printed either in the RILEM journal Materials and Structures or separately. Several test recommendations have been elaborated and will be prepared as drafts for the participants ofISAP '86. These are: - direct tensile test - pull-off test - direct shear test - slant shear test - four-point bending test - dynamic loading test - thermal compatibility test (two versions) - injectibility test.
Download or read book Bio aggregate based Building Materials written by Sofiane Amziane and published by John Wiley & Sons. This book was released on 2013-02-05 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt: Using plant material as raw materials for construction is a relatively recent and original topic of research. This book presents an overview of the current knowledge on the material properties and environmental impact of construction materials made from plant particles, which are renewable, recyclable and easily available. It focuses on particles and as well on fibers issued from hemp plant, as well as discussing hemp concretes. The book begins by setting the environmental, economic and social context of agro-concretes, before discussing the nature of plant-based aggregates and binders. The formulation, implementation and mechanical behavior of such building materials are the subject of the following chapters. The focus is then put upon the hygrothermal behavior and acoustical properties of hempcrete, followed by the use of plant-based concretes in structures. The book concludes with the study of life-cycle analysis (LCA) of the environmental characteristics of a banked hempcrete wall on a wooden skeleton. Contents 1. Environmental, Economic and Social Context of Agro-Concretes, Vincent Nozahic and Sofiane Amziane. 2. Characterization of Plant-Based Aggregates. Vincent Picandet. 3. Binders, Gilles Escadeillas, Camille Magniont, Sofiane Amziane and Vincent Nozahic. 4. Formulation and Implementation, Christophe Lanos, Florence Collet, Gérard Lenain and Yves Hustache. 5. Mechanical Behavior, Laurent Arnaud, Sofiane Amziane, Vincent Nozahic and Etienne Gourlay. 6. Hygrothermal Behavior of Hempcrete, Laurent Arnaud, Driss Samri and Étienne Gourlay. 7. Acoustical Properties of Hemp Concretes, Philippe Glé, Emmanuel Gourdon and Laurent Arnaud. 8. Plant-Based Concretes in Structures: Structural Aspect – Addition of a Wooden Support to Absorb the Strain, Philippe Munoz and Didier Pipet. 9. Examination of the Environmental Characteristics of a Banked Hempcrete Wall on a Wooden Skeleton, by Lifecycle Analysis: Feedback on the LCA Experiment from 2005, Marie-Pierre Boutin and Cyril Flamin. About the Authors Sofiane Amziane is Professor and head of the Civil Engineering department at POLYTECH Clermont-Ferrand in France. He is also in charge of the research program dealing with bio-based building materials at Blaise Pascal University (Institut Pascal, Clermont Ferrand, France). He is the secretary of the RILEM Technical Committee 236-BBM dealing with bio-based building materials and the author or co-author of over one hundred papers in scientific journals such as Cement and Concrete Research, Composite Structures or Construction Building Materials as well as international conferences. Laurent Arnaud is a Bridges, Waters and Forestry Engineer (Ingénieur des Ponts, Eaux et Forêts) and researcher at Joseph Fourier University in Grenoble, France. He is also Professor at ENTPE (Ecole Nationale des Travaux Publics de l’Etat). Trained in the field of mechanical engineering, his research has been directed toward the characterization and development of new materials for civil engineering and construction. He is head of the international committee at RILEM – BBM, as well as the author of more than one hundred publications, and holder of an international invention patent.
Download or read book Properties of UO2 written by J. Belle and published by . This book was released on 1957 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Handbook of Thermoset Plastics written by Olga Shepelev and published by Elsevier Inc. Chapters. This book was released on 2013-11-28 with total page 143 pages. Available in PDF, EPUB and Kindle. Book excerpt: With recent developments in nanotechnology, thermoset nanocomposites offer numerous advantages compared to conventional composite materials. Moreover, with the emergence of commercial nanomaterials like nanoclays (NCs), carbon nanotubes (CNTs), nanosilica (NS), Polyhedral-Oligomeric-Sil-Sesquioxanes (POSS), tungsten-disulfide (WS2) fullerenes and tubes, and Graphene (Gr), new potential routes have been opened to tailor thermosetting polymers in the nanoscale range. Due to the large surface area of the nanosize particles, only small amounts are needed to cause significant changes in the mechanical, physical, and thermal properties of polymer nanocomposites. When the surface areas of the nanoparticles are modified, additional dimensions for the formulation of structural adhesives and composite matrices arise, and can be used for a variety of applications. The formulation sequence and conditions are found to determine the structure and properties of the resulting nanocomposites. This chapter reviews and analyzes the various thermoset nanocomposites containing: NCs, CNTs, NS, POSS, WS2, and Gr.
Download or read book Fiber Plants written by K.G. Ramawat and published by Springer. This book was released on 2016-10-27 with total page 263 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book assesses the potential effects of biotechnological approaches, particularly genetic modification, on the present state of fiber crop cultivation and sustainable production. Leading international researchers discuss and explain how biotechnology can affect and solve problems in connection with fiber crops. The topics covered include biology, biotechnology, genomics and applications of fiber crops like cotton, flax, jute and bamboo. Providing complete, comprehensive and broad subject-based reviews, the book offers a valuable resource for students, teachers, and researchers including agriculturists, biotechnologists and botanists, as well as industrialists and government agencies involved in the planning of fiber crop cultivation.
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 Routledge International Handbook of Ignorance Studies written by Matthias Gross and published by Routledge. This book was released on 2015-05-15 with total page 427 pages. Available in PDF, EPUB and Kindle. Book excerpt: Once treated as the absence of knowledge, ignorance today has become a highly influential topic in its own right, commanding growing attention across the natural and social sciences where a wide range of scholars have begun to explore the social life and political issues involved in the distribution and strategic use of not knowing. The field is growing fast and this handbook reflects this interdisciplinary field of study by drawing contributions from economics, sociology, history, philosophy, cultural studies, anthropology, feminist studies, and related fields in order to serve as a seminal guide to the political, legal and social uses of ignorance in social and political life. Chapter 33 of this book is freely available as a downloadable Open Access PDF under a Creative Commons Attribution-Non Commercial-No Derivatives 4.0 license available here: https://tandfbis.s3-us-west-2.amazonaws.com/rt-files/docs/Open+Access+Chapters/9780415718967_oachapter33.pdf
Download or read book In Vessel Melt Retention and Ex Vessel Corium Cooling IAEA Tecdoc No 1906 written by International Atomic Energy Agency and published by International Atomic Energy Agency. This book was released on 2020-08-06 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt: This publication results from a technical meeting on phenomenology and technologies relevant to in-vessel melt retention (IVMR) and ex-vessel corium cooling (EVCC). The purpose of the publication is to capture the state of knowledge, at the time of that meeting, related to phenomenology and technologies as well as the challenges and pending issues relevant to IVMR and EVCC for water cooled reactors by summarizing the information provided by the meeting participants in a form useful to practitioners in Member States.
Download or read book Quantum Theory and Symmetries written by M. B. Paranjape and published by Springer Nature. This book was released on 2021 with total page 670 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume of the CRM Conference Series is based on a carefully refereed selection of contributions presented at the "11th International Symposium on Quantum Theory and Symmetries", held in Montreal, Canada from July 1-5, 2019. The main objective of the meeting was to share and make accessible new research and recent results in several branches of Theoretical and Mathematical Physics, including Algebraic Methods, Condensed Matter Physics, Cosmology and Gravitation, Integrability, Non-perturbative Quantum Field Theory, Particle Physics, Quantum Computing and Quantum Information Theory, and String/ADS-CFT. There was also a special session in honour of Decio Levi. The volume is divided into sections corresponding to the sessions held during the symposium, allowing the reader to appreciate both the homogeneity and the diversity of mathematical tools that have been applied in these subject areas. Several of the plenary speakers, who are internationally recognized experts in their fields, have contributed reviews of the main topics to complement the original contributions. .
Download or read book Sound Absorbing Materials written by E. J. Evans and published by . This book was released on 1960 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Materials and Structures written by Moussa Karama and published by Trans Tech Publications Ltd. This book was released on 2013-04-10 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt: Special topic volume with invited peer reviewed papers only
