Download or read book Applicability of the Continuum Shell Theories to the Mechanics of Carbon Nanotubes written by Vasyl Michael Harik and published by . This book was released on 2002 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: Validity of the assumptions relating the applicability of continuum shell theories to the global mechanical behavior of carbon nanotubes is examined. The present study focuses on providing a basis that can be used to qualitatively assess the appropriateness of continuum-shell models for nanotubes. To address the effect of nanotube structure on their deformation, all nanotube geometries are divided into four major classes that require distinct models. Criteria for the applicability of continuum models are presented. The key parameters that control the buckling strains and deformation modes of these classes of nanotubes are determined. In an analogy with continuum mechanics, mechanical laws of geometric similitude are presented. A parametric map is constructed for a variety of nanotube geometries as a guide for the applicability of different models. The continuum assumptions made in representing a nanotube as a homogeneous thin shell are analyzed to identify possible limitations of applying shell theories and using their bifurcation-buckling equations at the nano-scale.

Download or read book Mechanics of Carbon Nanotubes written by Vasyl Harik and published by Academic Press. This book was released on 2018-07-27 with total page 327 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mechanics of Carbon Nanotubes: Fundamentals, Modeling and Safety draws on the latest academic research and nanotechnology applications to provide a comprehensive guide on the most recent developments in the science of carbon nanotubes. The fundamentals of nanomechanics and mechanical behavior of carbon nanotubes are presented in initial chapters, followed by more advanced topics such as the classification of carbon nanotubes, carbon nanotubes in nanocomposites, multiwall carbon nanotubes, and recent trends.This book provides a system for the classification of carbon nanotubes into 20 classes, aiding correct selection for various applications, and includes the Atomic Registry Matrix Analysis for nanoscale interfaces, essential for design involving friction or sliding. Parametric maps are included to help readers pick the correct model for a particular CNT geometry, in addition to a thorough examination of the effective thickness paradox and safety issues related to CNTs, such as toxicity at high aspect ratio.Mechanics of Carbon Nanotubes is essential reading for anyone involved in research or engineering that includes carbon nanotubes, be they students or seasoned professionals in the field. It is particularly useful to those working with applications in the areas of microelectronics, robotics, aerospace, composites, or prosthetics. - Provides a system for the classification of carbon nanotubes, aiding correct selection for various applications - Includes the Matrix Registry Analysis for nanoscale interfaces that is essential for design involving friction or sliding - Features parametric maps to help readers pick the right model for a particular CNT geometry (beam vs. shell vs. thin or thick shells, etc.) - Presents a thorough examination of the safety issues related to CNTs, including toxicity at high aspect ratio

Download or read book Recent Developments in Modeling and Applications of Carbon Nanotubes written by Q. Wang and published by . This book was released on 2009-01-01 with total page 201 pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon nanotubes are macromolecules of carbon in a periodic hexagonal arrangement with a cylindrical shell shape. Carbon nanotubes have been subjected to extensive research, with subsequent predictions of extremely high strength and exceptional electronic and thermal properties. They also hold substantial promise as fibers in composites and other devices for the development of superconductive devices for micro-electro-mechanical and nano-electro-mechanical system applications. It is expected that the material has great potential in biological, medical, energy storage, sensor, and other applications. It has been broadly recognized that atomic modeling of carbon nanotube is a powerful tool for analysis of carbon nanotube. Due to massive computations involved, the atomic modeling is limited to systems with a small number of molecules and atoms. On the other hand, attempts at applying continuum mechanics models to better investigate the analysis of carbon nanotube with large sizes have been initiated. However, continuum models are unable to adequately capture the atomic structures of carbon nanotube, and the applicability of the models needs to be justified. Recently, developments of multiscale methods have been proposed to the analysis of carbon nanotube. This book is dedicated to the publication of recent developments in modeling of carbon nanotube via atomic modeling, continuum modeling and multiscale methods for predictions of mechanical, electronic, and thermal properties of carbon nanotube. A wide range of fundamentally theoretical, computational topics on modeling and applications of carbon nanotube will be covered in the book. In addition, applications of carbon nanotubes as nano-devices in atomic and molecular transportations and bistable devices in switching or memory elements in signal processing and communications are also reported. It is with great pleasure that we present this book that covers a very wide and varied range of subject areas in modeling and applications of carbon nanotubes. The first chapter employs molecular dynamics simulations to show macroscopic flows of atomic and molecular hydrogen, helium, and a mixture of both gases both inside and outside a carbon nanotube. In particular, the simulations show a nanoseparation effect of the two gases. The new results in the chapter show the mass selectivity of the nanopumping effect can be used to develop a highly selective filter for various gases. The second chapter introduces a fine continuum model that is developed by virtue of the higher-order continuum theory. Moreover, a mesh-free computational framework is developed to implement the numerical simulation of single- walled carbon nanotubes. The rationality of the higher-order continuum model and the efficiency of mesh-free method are illustrated and discussed in the chapter. The study on the mechanics of buckled single-walled and multiwalled carbon nanotubes, carbon nanotube bundles and coupling effect between adjacent carbon nanotubes is reported in chapter three. Simple expressions of the buckle wavelength, amplitude and critical strain for buckling are given analytically, which show good agreement with experiments. Chapter 4 investigate the applicability of elastic shell model in analysis of graphene and carbon nanotubes. The author reports that the elasticity of graphene should be modeled as a shell composed of 2-dimensional (2D) isotropic materials with proper parameters rather than conventional 3D materials based on calculations by density functional theory. In addition, the elasticity of single-walled carbon nanotube with relative large radius can also be modeled as a shell composed of 2D isotropic materials, whereas the elasticity of single-walled carbon nanotubes with relative small radius should be modeled as a more complicated shell with seven elastic constants rather than the orthotropic thin shell. Mechanical integrity of carbon nanotubes is summarized in chapter 5. Young s modulus for the resistance to the infinitesimal deformation and ultimate strength to the finite deformation are tabled, which have been obtained by experiments, molecular dynamics simulations, and ab-initio calculations. Also the recent continuous modeling of carbon nanotubes is sorted out in tracing its advancement in the chapter. Chapter 6 presents an overview of studies on the wave propagation and the vibrational properties in carbon nanotubes by computational modeling and simulation. The models include the atomic-based continuum model, the Euler-beam model, the Timoshenko beam model, and the three-dimensional elastic shell model. Chapter seven reports the investigations of torsional buckling of both single-walled and double-walled carbon nanotubes. In the study of doubled-walled carbon nanotubes via molecular dynamics, a newly revealed buckling mode with one or three thin local rims on the outer tube is discovered while the inner tube shows a helically aligned buckling mode in three dimensions. The distinct buckling modes of the two tubes imply the inapplicability of continuum mechanics modeling in which it is postulated that the buckling modes of the constituent tubes have the same shape. The mechanical properties of single walled carbon nanotubes under both tensile and torsion are investigated using classical molecular dynamics simulations in chapter 8, based on reactive empirical bond-order potential. Based on the predicted mechanical properties, it is predicted that nanotubes may represent new candidates for novel porous, flexible and high strength and tough materials, e.g. ideal as scaffolds in the regenerative medicine. Bistable devices have been widely used as switching or memory elements in signal processing and communications. The bistablity is generally realized electrically or optically. Due to their small size and unique mechanical properties, carbon nanotubes have been proposed to form bistable devices mechanically. The chapter 9 reviews the recent advances of mechanical bistable devices of carbon nanotubes. In the final chapter, the authors have discussed a theoretical model based on kinetic concept of fracture of solids and molecular mechanics simulations for studying the time-dependent behavior of single-walled carbon nanotubes. The major advantage of this model is that the problem of real-time molecular level simulation is circumvented. Compared with recently published data on creep rupture of SWCNT ropes, it is seen that the predictions by the present model is quite reasonable, thus setting up a framework for modeling the time-dependent behavior of carbon nanotubes and their composites. We would like to extend our sincere thanks to the authors for their contributions, especially their precious time and efforts invested in the book. We also would like to thank Transworld Research Network Publishers for the opportunity to publish the book to address very important and challenging issues. The support and love from our families are deeply appreciated.

Download or read book Computational Continuum Mechanics of Nanoscopic Structures written by Esmaeal Ghavanloo and published by Springer. This book was released on 2019-02-19 with total page 281 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book offers a comprehensive treatment of nonlocal elasticity theory as applied to the prediction of the mechanical characteristics of various types of biological and non-biological nanoscopic structures with different morphologies and functional behaviour. It combines fundamental notions and advanced concepts, covering both the theory of nonlocal elasticity and the mechanics of nanoscopic structures and systems. By reporting on recent findings and discussing future challenges, the book seeks to foster the application of nonlocal elasticity based approaches to the emerging fields of nanoscience and nanotechnology. It is a self-contained guide, and covers all relevant background information, the requisite mathematical and computational techniques, theoretical assumptions, physical methods and possible limitations of the nonlocal approach, including some practical applications. Mainly written for researchers in the fields of physics, biophysics, mechanics, and nanoscience, as well as computational engineers, the book can also be used as a reference guide for senior undergraduate and graduate students, as well as practicing engineers working in a range of areas, such as computational condensed matter physics, computational materials science, computational nanoscience and nanotechnology, and nanomechanics.

Download or read book Equivalent Continuum Modeling With Application to Carbon Nanotubes written by and published by . This book was released on 2002 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: A method has been proposed for developing structure-property relationships of nano-structured materials. This method serves as a link between computational chemistry and solid mechanics by substituting discrete molecular structures with equivalent-continuum models. It has been shown that this substitution may be accomplished by equating the vibrational potential energy of a nano-structured material with the strain energy of representative truss and continuum models. As important examples with direct application to the development and characterization of single-walled carbon nanotubes and the design of nanotube-based devices, the modeling technique has been applied to determine the effective-continuum geometry and bending rigidity of a graphene sheet, A representative volume element of the chemical structure of graphene has been substituted with equivalent-truss and equivalent-continuum models. As a result, an effective thickness of the continuum model has been determined.

Download or read book Computational Physics of Carbon Nanotubes written by Hashem Rafii-Tabar and published by Cambridge University Press. This book was released on 2008 with total page 477 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the key theories, computational modelling and numerical simulation tools required to understand carbon nanotube physics. Specifically, methods applied to geometry and bonding, mechanical, thermal, transport and storage properties are addressed. This self-contained book will interest researchers across a broad range of disciplines.

Download or read book Carbon Nanotubes and Nanosensors written by Isaac Elishakoff and published by John Wiley & Sons. This book was released on 2013-03-04 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main properties that make carbon nanotubes (CNTs) a promising technology for many future applications are: extremely high strength, low mass density, linear elastic behavior, almost perfect geometrical structure, and nanometer scale structure. Also, CNTs can conduct electricity better than copper and transmit heat better than diamonds. Therefore, they are bound to find a wide, and possibly revolutionary use in all fields of engineering. The interest in CNTs and their potential use in a wide range of commercial applications; such as nanoelectronics, quantum wire interconnects, field emission devices, composites, chemical sensors, biosensors, detectors, etc.; have rapidly increased in the last two decades. However, the performance of any CNT-based nanostructure is dependent on the mechanical properties of constituent CNTs. Therefore, it is crucial to know the mechanical behavior of individual CNTs such as their vibration frequencies, buckling loads, and deformations under different loadings. This title is dedicated to the vibration, buckling and impact behavior of CNTs, along with theory for carbon nanosensors, like the Bubnov-Galerkin and the Petrov-Galerkin methods, the Bresse-Timoshenko and the Donnell shell theory.

Download or read book Trends in Nanoscale Mechanics written by Vasyl Harik and published by Springer. This book was released on 2014-08-19 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains a collection of the state-of-the-art reviews written by the leading researchers in the areas of nanoscale mechanics, molecular dynamics, nanoscale modeling of nanocomposites and mechanics of carbon nanotubes. No other book provides reviews of recent discoveries such as a nanoscale analog of the Pauli’s principle, i.e., effect of the spatial exclusion of electrons or the SEE effect, a new Registry Matrix Analysis for the nanoscale interfacial sliding and new data on the effective viscosity of interfacial electrons in nanoscale stiction at the interfaces. This volume is also an exceptional resource on the well tested nanoscale modeling of carbon nanotubes and nanocomposites, new nanoscale effects, unique evaluations of the effective thickness of carbon nanotubes under different loads, new data on which size of carbon nanotubes is safer and many other topics. Extensive bibliography concerning all these topics is included along with the lucid short reviews. Numerous illustrations are provided for molecular dynamic simulations, fascinating nanoscale phenomena and remarkable new effects. It is of interest to a wide range of researchers and students.

Download or read book Size Dependent Continuum Mechanics Approaches written by Esmaeal Ghavanloo and published by Springer Nature. This book was released on 2021-04-02 with total page 463 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book offers a comprehensive and timely report of size-dependent continuum mechanics approaches. Written by scientists with worldwide reputation and established expertise, it covers the most recent findings, advanced theoretical developments and computational techniques, as well as a range of applications, in the field of nonlocal continuum mechanics. Chapters are concerned with lattice-based nonlocal models, Eringen’s nonlocal models, gradient theories of elasticity, strain- and stress-driven nonlocal models, and peridynamic theory, among other topics. This book provides researchers and practitioners with extensive and specialized information on cutting-edge theories and methods, innovative solutions to current problems and a timely insight into the behavior of some advanced materials and structures. It also offers a useful reference guide to senior undergraduate and graduate students in mechanical engineering, materials science, and applied physics.

Download or read book Wave Propagation in Nanostructures written by Srinivasan Gopalakrishnan and published by Springer Science & Business Media. This book was released on 2013-09-10 with total page 365 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wave Propagation in Nanostructures describes the fundamental and advanced concepts of waves propagating in structures that have dimensions of the order of nanometers. The book is fundamentally based on non-local elasticity theory, which includes scale effects in the continuum model. The book predominantly addresses wave behavior in carbon nanotubes and Graphene structures, although the methods of analysis provided in this text are equally applicable to other nanostructures. The book takes the reader from the fundamentals of wave propagation in nanotubes to more advanced topics such as rotating nanotubes, coupled nanotubes, and nanotubes with magnetic field and surface effects. The first few chapters cover the basics of wave propagation, different modeling schemes for nanostructures and introduce non-local elasticity theories, which form the building blocks for understanding the material provided in later chapters. A number of interesting examples are provided to illustrate the important features of wave behavior in these low dimensional structures.

Download or read book Nonlocal Continuum Shell Models for Torsion of Single walled Carbon Nanotubes written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon nanotubes (CNTs) have attracted much attention from scientists and engineers because of their relevance to a wide range of applications. Various approaches have been used for the characterization of CNT properties, among which continuum modeling has generated much interest due to computational efficiency. However, at the nanoscale the dimensions of a system are comparable to the inter-atomic or inter-molecular spacing of that system, and the material cannot be modeled as a continuum. This is known as the "size-effect". To overcome the limitations of classical continuum mechanics, modified continuum models have been proposed, among which models based on the concept of nonlocal elasticity have proven effective in quantifying the size-dependent mechanical response of CNTs. This thesis investigates the "small-size" effects in the torsional response of single walled carbon nanotubes (SWCNTs) by developing a modified nonlocal continuum shell model for their torsion. The purpose is to facilitate the design of devices based on CNT torsion by providing a simple, accurate and efficient continuum model that can predict the torsional buckling loads, the frequency of torsional vibrations and the propagation speed of torsional waves. To this end, Eringen's equations of nonlocal elasticity are incorporated into the classical models for torsion of cylindrical shells given by Timoshenko and Donnell. In contrast to the classical models, the nonlocal model developed here predicts non-dimensional buckling loads that depend on the values of certain geometric parameters of the CNT, allowing for the inclusion of size-effects. In the case of torsional vibrations and propagation of torsional waves, the classical and nonlocal models predict non-dispersive and dispersive behavior, respectively. Molecular dynamics simulations of torsional buckling, axial buckling and torsional vibration of various SWCNTs are also performed, the results of which are compared with the classical and nonloc.

Download or read book Mechanics of Carbon Nanotubes A Continuum Theory Incorporating Interatomic Potentials written by Peng Zhang and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modeling of Carbon Nanotubes Graphene and their Composites written by Konstantinos I. Tserpes and published by Springer Science & Business Media. This book was released on 2013-10-15 with total page 341 pages. Available in PDF, EPUB and Kindle. Book excerpt: A large part of the research currently being conducted in the fields of materials science and engineering mechanics is devoted to carbon nanotubes and their applications. In this process, modeling is a very attractive investigation tool due to the difficulties in manufacturing and testing of nanomaterials. Continuum modeling offers significant advantages over atomistic modeling. Furthermore, the lack of accuracy in continuum methods can be overtaken by incorporating input data either from experiments or atomistic methods. This book reviews the recent progress in continuum modeling of carbon nanotubes and their composites. The advantages and disadvantages of continuum methods over atomistic methods are comprehensively discussed. Numerical models, mainly based on the finite element method, as well as analytical models are presented in a comparative way starting from the simulation of isolated pristine and defected nanotubes and proceeding to nanotube-based composites. The ability of continuum methods to bridge different scales is emphasized. Recommendations for future research are given by focusing on what still continuum methods have to learn from the nano-scale. The scope of the book is to provide current knowledge aiming to support researchers entering the scientific area of carbon nanotubes to choose the appropriate modeling tool for accomplishing their study and place their efforts to further improve continuum methods.

Download or read book Modeling Characterization and Production of Nanomaterials written by and published by Elsevier. This book was released on 2015-03-17 with total page 555 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nano-scale materials have unique electronic, optical, and chemical properties which make them attractive for a new generation of devices. Part one of Modeling, Characterization, and Production of Nanomaterials: Electronics, Photonics and Energy Applications covers modeling techniques incorporating quantum mechanical effects to simulate nanomaterials and devices, such as multiscale modeling and density functional theory. Part two describes the characterization of nanomaterials using diffraction techniques and Raman spectroscopy. Part three looks at the structure and properties of nanomaterials, including their optical properties and atomic behaviour. Part four explores nanofabrication and nanodevices, including the growth of graphene, GaN-based nanorod heterostructures and colloidal quantum dots for applications in nanophotonics and metallic nanoparticles for catalysis applications. Comprehensive coverage of the close connection between modeling and experimental methods for studying a wide range of nanomaterials and nanostructures Focus on practical applications and industry needs, supported by a solid outlining of theoretical background Draws on the expertise of leading researchers in the field of nanomaterials from around the world

Download or read book Journal of Computational and Theoretical Nanoscience written by and published by . This book was released on 2005 with total page 662 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modeling Characterization and Production of Nanomaterials written by Vinod Tewary and published by Woodhead Publishing. This book was released on 2022-11-09 with total page 628 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nano-scale materials have unique electronic, optical, and chemical properties that make them attractive for a new generation of devices. In the second edition of Modeling, Characterization, and Production of Nanomaterials: Electronics, Photonics, and Energy Applications, leading experts review the latest advances in research in the understanding, prediction, and methods of production of current and emerging nanomaterials for key applications. The chapters in the first half of the book cover applications of different modeling techniques, such as Green's function-based multiscale modeling and density functional theory, to simulate nanomaterials and their structures, properties, and devices. The chapters in the second half describe the characterization of nanomaterials using advanced material characterization techniques, such as high-resolution electron microscopy, near-field scanning microwave microscopy, confocal micro-Raman spectroscopy, thermal analysis of nanoparticles, and applications of nanomaterials in areas such as electronics, solar energy, catalysis, and sensing. The second edition includes emerging relevant nanomaterials, applications, and updated modeling and characterization techniques and new understanding of nanomaterials. - Covers the close connection between modeling and experimental methods for studying a wide range of nanomaterials and nanostructures - Focuses on practical applications and industry needs through a solid outlining of the theoretical background - Includes emerging nanomaterials and their applications in spintronics and sensing

Download or read book Analysis of Shells Plates and Beams written by Holm Altenbach and published by Springer Nature. This book was released on 2020-06-03 with total page 470 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book commemorates the 75th birthday of Prof. George Jaiani – Georgia’s leading expert on shell theory. He is also well known outside Georgia for his individual approach to shell theory research and as an organizer of meetings, conferences and schools in the field. The collection of papers presented includes articles by scientists from various countries discussing the state of the art and new trends in the theory of shells, plates, and beams. Chapter 20 is available open access under a Creative Commons Attribution 4.0 International License via link.springer.com.