Download or read book Theory and Measurements of Thermal Properties in Nanowires and Carbon Nanotubes written by Michael F. P. Bifano and published by . This book was released on 2012 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt: The extraordinary potential of nanoscale materials and nano-constituent composite materials coupled with rapid progress in the capability to synthesize these materials has created a demand for their property characterization. To develop a better understanding of thermal transport in nanoscale wires and nanotubes, this thesis utilizes both theoretical and experimental techniques to determine how nanostructure geometry, surface properties, and heat treatment affect their ability to conduct thermal energy. As an example, the effect of heat treatment on the thermal conductivity of commercially available, chemical vapor deposition-grown, multiwalled carbon nanotubes (MWCNTs) is presented. The measurement device is implemented inside a scanning electron microscope equipped with nanomanipulators and a gas injected electron beam deposition system for repeatable in-situ sample characterization. MWCNT samples treated to 3000 C show a 5-fold increase in average thermal conductivity as compared to the as-synthesized samples. By including an estimation of thermal contact resistance due to phonon impedance mismatch, the average thermal conductivity of the heat-treated MWCNT specimens is estimated to be 228 W/m-K. The results suggest that heat treatment is a viable method to improve thermal conductivity and highlight the importance of MWCNTs quality in thermal management applications. Classical MD simulations are used to investigate the sensitivity of thermal conductivity to side-wall defects in SWCNTs. Vacancy repair is evident with heat treatment. 3000 C heat treatment of SWCNTs having varying degrees of defect concentrations is found to generally increase thermal conductivity by at least 10 %. The results suggest that phonon mean free path in (6,6) SWCNTs is nearly equally impeded by side-wall functionalization as compared to atomic vacancies. Classical MD simulations estimate that 2 atom % of hydrogenation and 1.5 - 2 % vacancy concentrations reduce thermal conductivity to the same degree. As compared to non-functionalized SWCNTs, the results suggest that the use of chemically functionalized SWCNTs as a second phase material in multifunctional CNT-polymer composites may reduce thermal transport. Nanoscale effects on thermal properties are further evaluated by an investigation into the dependency of specific heat and ballistic thermal conductance on cross-sectional geometry in free-standing isotropic non-metallic crystalline nanostructures. Analysis of phonon confinement is performed using dispersion relations found by numerically solving the Pochhammer-Chree frequency equation for a tube. These dispersion relations are used to evaluate the specific heat and ballistic thermal conductance in the nanostructures as a function of the nanostructure geometry, size, and surface stiffness. 1D, 2D, and 3D geometric phonon confinement regimes are recognized and found to depend on both the nanostructure's wall thickness and outer radius. Compared to nanowires, the frequency reduction of acoustic phonon modes in thinner walled nanotubes is shown to elevate the ballistic thermal conductance of the thin-walled nanotube between 0.2 K and 150 K. At 20 K, the ballistic thermal conductance of the thin-walled nanotube is found to be 300% greater than that of a solid nanowire. Surface modification of nanotubes and nanowires is performed using a multilayer elastic model to increase the average Young's modulus of the first three atomic surface layers. The acoustic stiffening of the interior and exterior lateral walls of nanotubes is found to have a contrasting effect on specific heat and thermal conductivity as compared to the outer surface modification of the nanowire. A 10% reduction in specific heat and a 2% reduction in lattice thermal conductivity at 50 K occur in a crystalline nanotube having a 10 nm outer and 5 nm inner diameter. In contrast, at the same temperature, an approximate 30% increase in thermal conductivity and specific heat occurs when the acoustically stiffened surface is applied to the outer diameter of a nanowire with a solid cross-sectional area. The simplified model has the potential to investigate the acoustic engineering of nanowires and nanotubes by inducing surface stiffening or softening via appropriate surface chemical functionalization protocols or coatings.
Download or read book A Study of the Thermal Properties of Commercially Available Multi walled Carbon Nanotubes and Gold Nanowires written by Kyle Otte and published by . This book was released on 2013 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nanoscale Thermoelectrics written by Xiaodong Wang and published by Springer Science & Business Media. This book was released on 2013-11-18 with total page 520 pages. Available in PDF, EPUB and Kindle. Book excerpt: For the efficient utilization of energy resources and the minimization of environmental damage, thermoelectric materials can play an important role by converting waste heat into electricity directly. Nanostructured thermoelectric materials have received much attention recently due to the potential for enhanced properties associated with size effects and quantum confinement. Nanoscale Thermoelectrics describes the theory underlying these phenomena, as well as various thermoelectric materials and nanostructures such as carbon nanotubes, SiGe nanowires, and graphene nanoribbons. Chapters written by leading scientists throughout the world are intended to create a fundamental bridge between thermoelectrics and nanotechnology, and to stimulate readers' interest in developing new types of thermoelectric materials and devices for power generation and other applications. Nanoscale Thermoelectrics is both a comprehensive introduction to the field and a guide to further research, and can be recommended for Physics, Electrical Engineering, and Materials Science departments.
Download or read book Thermal Transport in Carbon Based Nanomaterials written by Gang Zhang and published by Elsevier. This book was released on 2017-06-13 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thermal Transport in Carbon-Based Nanomaterials describes the thermal properties of various carbon nanomaterials and then examines their applications in thermal management and renewable energy. Carbon nanomaterials include: one-dimensional (1D) structures, like nanotubes; two-dimensional (2D) crystal lattice with only one-atom-thick planar sheets, like graphenes; composites based on carbon nanotube or graphene, and diamond nanowires and thin films. In the past two decades, rapid developments in the synthesis and processing of carbon-based nanomaterials have created a great desire among scientists to gain a greater understanding of thermal transport in these materials. Thermal properties in nanomaterials differ significantly from those in bulk materials because the characteristic length scales associated with the heat carriers, phonons, are comparable to the characteristic length. Carbon nanomaterials with high thermal conductivity can be applied in heat dissipation. This looks set to make a significant impact on human life and, with numerous commercial developments emerging, will become a major academic topic over the coming years. This authoritative and comprehensive book will be of great use to both the existing scientific community in this field, as well as for those who wish to enter it. - Includes coverage of the most important and commonly adopted computational and experimental methods to analyze thermal properties in carbon nanomaterials - Contains information about the growth of carbon nanomaterials, their thermal properties, and strategies to control thermal properties and applications, allowing readers to assess how to use each material most efficiently - Offers a comprehensive overview of the theoretical background behind thermal transport in carbon nanomaterials
Download or read book Thermal Nanosystems and Nanomaterials written by Sebastian Volz and published by Springer Science & Business Media. This book was released on 2009-12-24 with total page 597 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heat transfer laws for conduction, radiation and convection change when the dimensions of the systems in question shrink. The altered behaviours can be used efficiently in energy conversion, respectively bio- and high-performance materials to control microelectronic devices. To understand and model those thermal mechanisms, specific metrologies have to be established. This book provides an overview of actual devices and materials involving micro-nanoscale heat transfer mechanisms. These are clearly explained and exemplified by a large spectrum of relevant physical models, while the most advanced nanoscale thermal metrologies are presented.
Download or read book Thermal Transport in Individual Nanowires and Nanotubes written by Deyu Li and published by . This book was released on 2002 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Thermal Properties of Nanowires and Nanotubes written by Christopher Eric Dames and published by . This book was released on 2006 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: (Cont.) To facilitate further experimental studies of individual nanowires, the "3-omega" methods for thermal properties measurements were made more rigorous, simpler to implement, and generalized to 1-omega and 2-omega methods which may be advantageous for nanoscale systems. These methods are used to deduce the thermal properties of a system from its electrical response at the first, second, or third harmonic of a driving current. Finally, a detailed design and preliminary measurements are presented for a new type of hot-wire probe based on Wollaston wire and used to measure the thermoelectric properties of individual nanowires and nanotubes inside a transmission electron microscope.
Download or read book Thermal Conductivity written by Terry M. Tritt and published by Springer Science & Business Media. This book was released on 2006-10-03 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt: It has been almost thirty years since the publication of a book that is entirely dedicated to the theory, description, characterization and measurement of the thermal conductivity of solids. The recent discovery of new materials which possess more complex crystal structures and thus more complicated phonon scattering mechanisms have brought innovative challenges to the theory and experimental understanding of these new materials. With the development of new and novel solid materials and new measurement techniques, this book will serve as a current and extensive resource to the next generation researchers in the field of thermal conductivity. This book is a valuable resource for research groups and special topics courses (8-10 students), for 1st or 2nd year graduate level courses in Thermal Properties of Solids, special topics courses in Thermal Conductivity, Superconductors and Magnetic Materials, and to researchers in Thermoelectrics, Thermal Barrier Materials and Solid State Physics.
Download or read book Carbon Nanotubes written by Stephanie Reich and published by John Wiley & Sons. This book was released on 2008-09-26 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon nanotubes are exceptionally interesting from a fundamental research point of view. Many concepts of one-dimensional physics have been verified experimentally such as electron and phonon confinement or the one-dimensional singularities in the density of states; other 1D signatures are still under debate, such as Luttinger-liquid behavior. Carbon nanotubes are chemically stable, mechanically very strong, and conduct electricity. For this reason, they open up new perspectives for various applications, such as nano-transistors in circuits, field-emission displays, artificial muscles, or added reinforcements in alloys. This text is an introduction to the physical concepts needed for investigating carbon nanotubes and other one-dimensional solid-state systems. Written for a wide scientific readership, each chapter consists of an instructive approach to the topic and sustainable ideas for solutions. The former is generally comprehensible for physicists and chemists, while the latter enable the reader to work towards the state of the art in that area. The book gives for the first time a combined theoretical and experimental description of topics like luminescence of carbon nanotubes, Raman scattering, or transport measurements. The theoretical concepts discussed range from the tight-binding approximation, which can be followed by pencil and paper, to first-principles simulations. We emphasize a comprehensive theoretical and experimental understanding of carbon nanotubes including - general concepts for one-dimensional systems - an introduction to the symmetry of nanotubes - textbook models of nanotubes as narrow cylinders - a combination of ab-initio calculations and experiments - luminescence excitation spectroscopy linked to Raman spectroscopy - an introduction to the 1D-transport properties of nanotubes - effects of bundling on the electronic and vibrational properties and - resonance Raman scattering in nanotubes.
Download or read book Thermal Behaviour and Applications of Carbon Based Nanomaterials written by Dimitrios V. Papavassiliou and published by Elsevier. This book was released on 2020-04-15 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanocomposites with Carbon-based nanofillers (e.g., carbon nanotubes, graphene sheets and nanoribbons etc.) form a class of extremely promising materials for thermal applications. In addition to exceptional material properties, the thermal conductivity of the carbon-based nanofillers can be higher than any other known material, suggesting the possibility to engineer nanocomposites that are both lightweight and durable, and have unique thermal properties. This potential is hindered by thermal boundary resistance (TBR) to heat transfer at the interface between nanoinclusions and the matrix, and by the difficulty to control the dispersion pattern and the orientation of the nanoinclusions. Thermal Behaviour and Applications of Carbon-Based Nanomaterials: Theory, Methods and Applications explores heat transfer in nanocomposites, discusses techniques predicting and modeling the thermal behavior of carbon nanocomposites at different scales, and methods for engineering applications of nanofluidics and heat transfer. The chapters combine theoretical explanation, experimental methods and computational analysis to show how carbon-based nanomaterials are being used to optimise heat transfer. The applications-focused emphasis of this book makes it a valuable resource for materials scientists and engineers who want to learn more about nanoscale heat transfer. Offers an informed overview of how carbon nanomaterials are currently used for nanoscale heat transfer Discusses the major applications of carbon nanomaterials for heat transfer in a variety of industry sectors Details the major computational methods for the analysis of the thermal properties of carbon nanomaterials
Download or read book Mesoscopic Thermophysical Measurements of Microstructures and Carbon Nanotubes written by Li Shih and published by . This book was released on 2001 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nano Microscale Heat Transfer written by Zhuomin M. Zhang and published by Springer Nature. This book was released on 2020-06-23 with total page 780 pages. Available in PDF, EPUB and Kindle. Book excerpt: This substantially updated and augmented second edition adds over 200 pages of text covering and an array of newer developments in nanoscale thermal transport. In Nano/Microscale Heat Transfer, 2nd edition, Dr. Zhang expands his classroom-proven text to incorporate thermal conductivity spectroscopy, time-domain and frequency-domain thermoreflectance techniques, quantum size effect on specific heat, coherent phonon, minimum thermal conductivity, interface thermal conductance, thermal interface materials, 2D sheet materials and their unique thermal properties, soft materials, first-principles simulation, hyperbolic metamaterials, magnetic polaritons, and new near-field radiation experiments and numerical simulations. Informed by over 12 years use, the author’s research experience, and feedback from teaching faculty, the book has been reorganized in many sections and enriched with more examples and homework problems. Solutions for selected problems are also available to qualified faculty via a password-protected website.• Substantially updates and augments the widely adopted original edition, adding over 200 pages and many new illustrations;• Incorporates student and faculty feedback from a decade of classroom use;• Elucidates concepts explained with many examples and illustrations;• Supports student application of theory with 300 homework problems;• Maximizes reader understanding of micro/nanoscale thermophysical properties and processes and how to apply them to thermal science and engineering;• Features MATLAB codes for working with size and temperature effects on thermal conductivity, specific heat of nanostructures, thin-film optics, RCWA, and near-field radiation.
Download or read book High Thermal Conductivity Materials written by Subhash L. Shinde and published by Springer Science & Business Media. This book was released on 2006-01-31 with total page 285 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main objective of this book is to cover the basic understanding of thermal conduction mechanisms in various high thermal conductivity materials including diamond, cubic boron nitride, and also the latest material like carbon nanotubes. The book is intended as a good reference book for scientists and engineers involved in addressing thermal management issues in a broad spectrum of industries. Leading researchers from industry and academic institutions who are well known in their areas of expertise have contributed a chapter in the field of their interest.
Download or read book Micro and Nano Thermal Transport written by Lin Qiu and published by Academic Press. This book was released on 2022-02-09 with total page 358 pages. Available in PDF, EPUB and Kindle. Book excerpt: Micro and Nano Thermal Transport Research: Characterization, Measurement and Mechanism is a complete and reliable reference on thermal measurement methods and mechanisms of micro and nanoscale materials. The book has a strong focus on applications and simulation, providing clear guidance on how to measure thermal properties in a systematic way. Sections cover the fundamentals of thermal properties before introducing tools to help readers identify and analyze thermal characteristics of these materials. The thermal transport properties are then further explored by means of simulation which reflect the internal mechanisms used to generate such thermal properties. Readers will gain a clear understanding of thermophysical measurement methods and the representative thermal transport characteristics of micro/nanoscale materials with different structures and are guided through a decision-making process to choose the most effective method to master thermal analysis. The book is particularly suitable for those engaged in the design and development of thermal property measurement instruments, as well as researchers of thermal transport at the micro and nanoscale. - Includes a variety of measurement methods and thermal transport characteristics of micro and nanoscale materials under different structures - Guides the reader through the decision-making process to ensure the best thermal analysis method is selected for their setting - Contains experiments and simulations throughout that help apply understanding to practice
Download or read book Handbook of Nanophysics written by Klaus D. Sattler and published by CRC Press. This book was released on 2010-09-17 with total page 770 pages. Available in PDF, EPUB and Kindle. Book excerpt: Intensive research on fullerenes, nanoparticles, and quantum dots in the 1990s led to interest in nanotubes and nanowires in subsequent years. Handbook of Nanophysics: Nanotubes and Nanowires focuses on the fundamental physics and latest applications of these important nanoscale materials and structures. Each peer-reviewed chapter contains a broad-
Download or read book Thermal Properties of Nanofluids written by Taher Armaghani and published by CRC Press. This book was released on 2024-11-13 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thermal Properties of Nanofluids presents emerging prospects for understanding and controlling thermophysical properties at the nanoscale. It covers a comprehensive study of recent progress concerning these properties from the solid state to colloids and, above all, a different look at the effect of temperature on nanofluids’ thermal conducting. Introducing various techniques for measuring solid-state properties, including thermal conductivity, thermal diffusivity, and specific heat capacity, this book presents modeling approaches developed for predicting these properties by molecular dynamic (MD) simulations. It discusses the main factors that affect solid-state properties, such as grain size, grain boundaries, surface interactions, doping, and temperature, and the effects of all these factors. This book will interest industry professionals and academic researchers studying the thermophysical behavior of nanomaterials and heat transfer applications of nanofluids. It will serve graduate engineering students studying advanced fluid mechanics, heat transfer, and nanomaterials.
Download or read book Nanotube Superfiber Materials written by Michael B. Jakubinek and published by Elsevier Inc. Chapters. This book was released on 2013-09-16 with total page 49 pages. Available in PDF, EPUB and Kindle. Book excerpt: Individual carbon nanotubes (CNTs) have been reported to have the highest thermal conductivities of any known material. However, significant variability exists both for the reported thermal conductivities of individual CNTs and the thermal conductivities measured for macroscopic CNT assemblies (e.g. CNT films, buckypapers, arrays, and fibers), which range from comparable to metals to aerogel-like. This chapter reviews the current status of the field, summarizing a wide selection of experimental results and drawing conclusions regarding present limitations of the thermal conductivity of CNT assemblies and opportunities for improvement of the performance of nanotube superfiber materials.
