Download or read book Fabrication Modeling and Experimental Study of Bending Deformation of Micro ferrogel Fibers in a Non uniform Magnetic Field written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydrogel smart polymers have achieved a great attention in the research area of drug delivery, MEMS/NEMS, microfluidics and sensor design because of their responsiveness to various environmental stimuli- pH, temperature, light, electric field, enzyme etc. This thesis presents the modeling, fabrication and study of the bending deformation of magnetic field sensitive hydrogel micro fibers called ferrogels. The objective is to externally actuate the ferrogel fibers by applying magnetic field, for the application of targeted drug delivery inside the alveoli of a human lung. Prediction of the bending deformation of the ferrogel fibers is done by the Multiphysics Finite Element Modeling in an Arbitrary Lagrangian Eulerian (ALE) framework. Ferrogel micro fibers are fabricated and the bending deforma-tion is studied experimentally by varying the aspect ratio of the fibers, volume fraction of the magnetic particle content of the fibers and the magnetic field strength. The numerical and experimental results are compared. This is the first attempt to numerically predict the bending deformation of ferrogel micro-fibers.
Download or read book Fabrication Modeling and Experimental Study of Bending Deformation of Micro ferrogel Fibers in a Non uniform Magnetic Field written by Tasnuva Khaleque and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transverse Impact of Ballistic Fibers and Yarns written by Subramani Sockalingam and published by . This book was released on 2016 with total page 277 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ballistic impact onto flexible textile fabrics is a complicated multi-scale problem owing to the structural hierarchy of the materials, anisotropic material behavior, projectile geometry, impact velocity and boundary conditions. While this subject has been an active area of research for decades, the fundamental mechanisms such as material failure, dynamic response and multi-axial loading occurring at lower length scales during impact are not well understood. This work provides new insights into the fundamental deformation and failure mechanisms during ballistic impact onto textile fabrics at the micron length scale. In this research, a hybrid computational-experimental systematic approach is adopted to understand the mechanisms and deformation modes of high performance polymer fibers, specifically Kevlar KM2, that is widely used in ballistic impact applications. Fiber length-scale 3D finite element (FE) models are developed to better understand and complement the complicated transverse impact experiments. The fiber length-scale study suggests that fibers are subjected to multiaxial stress states including transverse compression, axial tension, axial compression and transverse shear significant enough to cause fibrillation in the fiber during impact. A dispersive flexural wave mode is predicted by the model due to the finite longitudinal shear modulus of the fiber. The flexural wave induces curvature in the fiber significant enough to cause compressive kinking and, in turn, local fibrillation in the fiber. A fiber length-scale yarn model is developed by explicitly modeling all the 400 fibers in a KM2 600 denier yarn. The yarn transverse compression results show that fiber-fiber contact plays a significant role in the spreading and deformation of individual fibers that is consistent with experimental results. When subjected to transverse impact, the model indicates significant transverse compressive strains in the fiber that increase with impact velocity and a flexural wave that induces curvatures in the fibers significant enough to induce compressive kinking and fibrillation. In addition to the transverse wave, a spreading wave develops due to fiber-fiber contact interaction that spreads the fibers to a large extent resulting in non-uniform loading and progressive failure of fibers within the yarn. Guided by the computational models, single-fiber micromechanical experiments for axial compressive kinking and transverse compression deformation modes are developed. The average tensile strength of the kinked fibers is found to be reduced by 7% compared to the virgin fibers. An experimental methodology is developed to determine the single fiber constitutive behavior in quasi-static transverse compression by removing the geometric nonlinearity due to the growing contact area. The fibers exhibit nonlinear inelastic behavior under large compressive strains. The fibers subjected to 60% nominal strains (80% true strains) showed a 20% reduction in average tensile strength compared to the virgin fibers. A nonlinear inelastic constitutive model is implemented as a user defined material (UMAT) suitable for the commercial FE code LS-DYNA explicit analysis. During impact, the inelastic behavior results in a significant reduction in the fiber bounce velocity and a reduction in the projectile-fiber contact forces by 40% compared to an elastic constitutive behavior. The inelastic dissipation and reduced bounce leads to an inelastic collision rather than an elastic collision. The longitudinal shear modulus and the inelastic behavior are found to govern the failure response of the fibers during impact. Modeling the single fiber quasi-static multiaxial loading experiments indicate fiber failure may be initiated based on a gage length dependent maximum axial tensile strain in the fiber. Regardless of the material behavior (elastic or inelastic), fiber length-scale impact models show a gradient in the axial tensile strain (stress) in the fiber cross section at the location of failure consistent with multiaxial loading experimental observations. Fiber-level yarn breaking speed predictions based on a maximum axial tensile strain (stress) criterion are much lower than the breaking speed based on classical theory and they are consistent with experimental measurements. Therefore, the reduction in experimental yarn breaking speed compared to theoretical Smith solution is attributed to the stress concentration and property degradation mechanisms due to multiaxial stress states at the location of failure.
Download or read book Experimental and Numerical Study of the Bending Behaviour of Textile Reinforcements and Thermoplastic Prepregs written by Biao Liang and published by . This book was released on 2019 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis is devoted to study the bending behaviour of textile reinforcements and thermoplastic prepregs by the experimental and numerical methods. At the high temperature, since the resin is melted, fibers would have the slippage between them, resulting the bending stiffness of thermoplastic prepreg is not directly related to its in-plane tensile modulus as the conventional continuous materials. Consequently, it's necessary to measure its value by the experimental method. A bending stiffness test approach was proposed for thermoplastic prepreg at elevated temperature. It was operated in an environmental chamber and a CCD camera was used to acquire the bending deflection shape. Bending moment and curvature were calculated along the midline of bending deflection shape. The slope of moment-curvature curve is the bending stiffness. With this method, bending tests were conducted for several types of thermoplastic prepregs at a range of high temperatures. In order to simulate the bending deformation of thick fibrous materials, a specific shell element was developed. This element was made of continuous fiber segments. Both the tensile and bending stiffnesses of fibers were taken into account. Local curve was constructed for any fiber segment and its two neighbors, which was used to characterize the tensile and bending deformations of fiber segment. Several bending simulation tests were performed with this specific shell element and were compared with the experimental results to show its efficiency. The results show this specific shell element has good capability to simulate the bending deformation of thick fibrous materials.
Download or read book Fundamentals of Smart Materials written by Mohsen Shahinpoor and published by Royal Society of Chemistry. This book was released on 2020-04-22 with total page 358 pages. Available in PDF, EPUB and Kindle. Book excerpt: This textbook covers the fundamentals of different functional material systems aimed at advanced undergraduate and postgraduate students. Each chapter includes an introduction to the material, its applications and uses with example problems, fabrication and manufacturing techniques, conclusions, homework problems and a bibliography. Edited by a leading researcher in smart materials, topics include piezoelectric materials, magnetostrictive materials, shape memory alloys, mechanochromic materials, chemomechanical polymers and self-healing materials.
Download or read book Electroactive Polymers for Robotic Applications written by Kwang J. Kim and published by Springer Science & Business Media. This book was released on 2007-01-17 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers the fundamental properties, modeling, and demonstration of Electroactive polymers in robotic applications. It particularly details artificial muscles and sensors. In addition, the book discusses the properties and uses in robotics applications of ionic polymer–metal composite actuators and dielectric elastomers.
Download or read book Soft Actuators written by Kinji Asaka and published by Springer Nature. This book was released on 2019-08-28 with total page 740 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is the second edition of Soft Actuators, originally published in 2014, with 12 chapters added to the first edition. The subject of this new edition is current comprehensive research and development of soft actuators, covering interdisciplinary study of materials science, mechanics, electronics, robotics, and bioscience. The book includes contemporary research of actuators based on biomaterials for their potential in future artificial muscle technology. Readers will find detailed and useful information about materials, methods of synthesis, fabrication, and measurements to study soft actuators. Additionally, the topics of materials, modeling, and applications not only promote the further research and development of soft actuators, but bring benefits for utilization and industrialization. This volume makes generous use of color figures, diagrams, and photographs that provide easy-to-understand descriptions of the mechanisms, apparatus, and motions of soft actuators. Also, in this second edition the chapters on modeling, materials design, and device design have been given a wider scope and made easier to comprehend, which will be helpful in practical applications of soft actuators. Readers of this work can acquire the newest technology and information about basic science and practical applications of flexible, lightweight, and noiseless soft actuators, which differ from conventional mechanical engines and electric motors. This new edition of Soft Actuators will inspire readers with fresh ideas and encourage their research and development, thus opening up a new field of applications for the utilization and industrialization of soft actuators.
Download or read book Nanotechnology Characterization Tools for Tissue Engineering and Medical Therapy written by Challa S.S.R. Kumar and published by Springer Nature. This book was released on 2019-11-22 with total page 467 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ninth volume of a 40 volume series on nanoscience and nanotechnology, edited by the renowned scientist Challa S.S.R. Kumar. This handbook gives a comprehensive overview about Nanotechnology Characterization Tools for Tissue Engineering and Medical Therapy. Modern applications and state-of-the-art techniques are covered and make this volume an essential reading for research scientists in academia and industry.
Download or read book Magnetorheology written by Norman Wereley and published by Royal Society of Chemistry. This book was released on 2014 with total page 410 pages. Available in PDF, EPUB and Kindle. Book excerpt: Leading experts provide a timely overview of the key developments in the physics, chemistry and uses of magnetorheological fluids.
Download or read book Cellular Solids written by Lorna J. Gibson and published by Cambridge University Press. This book was released on 1997 with total page 536 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this new edition of their classic work on Cellular Solids, the authors have brought the book completely up to date, including new work on processing of metallic and ceramic foams and on the mechanical, electrical and acoustic properties of cellular solids. Data for commercially available foams are presented on material property charts; two new case studies show how the charts are used for selection of foams in engineering design. Over 150 references appearing in the literature since the publication of the first edition are cited. The text summarises current understanding of the structure and mechanical behaviour of cellular materials, and the ways in which they can be exploited in engineering design. Cellular solids include engineering honeycombs and foams (which can now be made from polymers, metals, ceramics and composites) as well as natural materials, such as wood, cork and cancellous bone.
Download or read book Ferrofluids written by Stefan Odenbach and published by Springer. This book was released on 2008-01-11 with total page 255 pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnetic control of the properties and the flow of liquids is a challenging field for basic research and for applications. This book is meant to be both an introduction to, and a state-of-the-art review of, this topic. Written in the form of a set of lectures and tutorial reviews, the book addresses the synthesis and characterization of magnetic fluids, their hydrodynamical description and their rheological properties. The book closes with an account of magnetic drug targeting.
Download or read book Flow Induced Alignment in Composite Materials written by T. D. Papathanasiou and published by Woodhead Publishing. This book was released on 1997-10-21 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of aligning short fibers in a fiber-reinforced material is to improve the mechanical properties of the resulting composite. Aligning the fibers, generally in a preferred direction, allows them to contribute as much as possible to reinforcing the material. In some cases, the mechanical properties of these aligned, short-fiber composites can approach those of continuous-fiber composites, with the advantages of lower production costs and greater ease of production. Since its publication, this book has been consistently recognized as one of the most important contributions to this field.
Download or read book Nanocellulose Based Composites for Electronics written by Sabu Thomas and published by Elsevier. This book was released on 2020-10-06 with total page 358 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanocellulose Based Composites for Electronics presents recent developments in the synthesis and applications of nanocellulose composites in electronics, highlighting applications in various technologies. Chapters covers new trends and challenges in a wide range of electronic applications and devices. Significant properties, safety, sustainability, and environmental impacts of the electronic devices are included, along with the challenges of using nanocellulose-based composites in electronics. This book is an important reference for materials scientists and engineers configuring and designing processes for the synthesis and device fabrication of nanocellulose composites in electronics. Explores how to utilize nanocellulose fibers and nano-crystalline cellulose substances to synthesize materials with designed functionalities Outlines the major production processes for nanocellulous composites Discusses the major challenges that need to be surmounted in order to effectively use nanocellulous composites for electronics
Download or read book Nanotechnology in Regenerative Medicine and Drug Delivery Therapy written by Haiyan Xu and published by Springer Nature. This book was released on 2020-07-21 with total page 490 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book focuses on the application of nanotechnologies in scaffold-guided tissue regeneration and in drug delivery systems for use in immunotherapy and overcoming drug resistance in cancer treatment. It covers a variety of topics, including nanomaterials for immunomodulation and immnunotherapy; molecular studies on self-assembly for peptides and DNA and related applications in tumor diagnosis and therapeutics and against human pathogenic bacteria; magnetic and conductive scaffolds for guiding tissue regeneration; multiple functions of magnetic nanoparticles in drug delivery and regenerative medicine; and re-purposing of traditional medicine in nano-formulations. In addition, it discusses common effects of nanomaterials, including reactive oxygen species and protein corona. Providing valuable insights and the presenting the latest research advances, the book allows readers to gain a systematic understanding of the topic.
Download or read book Encyclopedia of Politics of the American West written by Steven L. Danver and published by CQ Press. This book was released on 2013-04-25 with total page 1566 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Encyclopedia of Politics in the American West is an A to Z reference work on the political development of one of America’s most politically distinct, not to mention its fastest growing, region. This work will cover not only the significant events and actors of Western politics, but also deal with key institutional, historical, environmental, and sociopolitical themes and concepts that are important to more fully understanding the politics of the West over the last century.
Download or read book Magnetic Properties of Metals and Alloys written by American Society for Metals and published by . This book was released on 1959 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Linear Theory written by A. Cemal Eringen and published by Academic Press. This book was released on 2013-10-22 with total page 676 pages. Available in PDF, EPUB and Kindle. Book excerpt: Elastodynamics, Volume II: Linear Theory is a continuation of Volume I and discusses the dynamical theory of linear isotropic elasticity. The volume deals with the fundamental theorems regarding elastodynamics and the different mathematical methods of solution and their employment in one, two, and three dimensions. The text outlines the fundamentals of linear elastodynamics and explains basic equations, displacement formulation, stress formulation, and the uniqueness theorem of elastodynamics. The book also investigates elastodynamic problems involving one-space dimension in governing boundaries, equations, and initial conditions. The book then compares two-dimensional problems as being subject to more precise mathematical analysis compared to three-dimensional situations by using scalar wave equations. The text then analyzes elastodynamic problems in three space dimensions when the solution depends on the condition of separability of the vector wave equation and the satisfaction of the boundary conditions. The diffraction of elastic waves is also described using two approaches: the integral equation method or the Eigen function technique. The book can prove valuable to researchers and practitioners whose work involves advanced statistics, general physics, and thermodynamics.
