Download or read book Self assembly of Lyotropic Chromonic Liquid Crystals written by Heung-Shik Park and published by . This book was released on 2010 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lyotropic chromonic liquid crystals (LCLCs) are composed of plank-like molecules with rigid polyaromatic cores and two or more ionic groups at the periphery. These molecules typically stack on top of each other leaving the ionic solubilizing groups at the aggregate-water interface. As the concentration of LCLC increases, the aggregates multiply, elongate, and align parallel to each other and then form mesophases. The two most commonly met phases in LCLCs are the uniaxial nematic phase and the columnar phase with aggregates forming a hexagonal lattice in the plane perpendicular to the average orientation of aggregates. This thesis explores how the aggregate structure and the phase diagrams of LCLCs in water depend on their concentration, temperature, pH of the solution, and the presence of various additives, such as salts and neutral polymers. The two main mechanisms associated with the role of additives are (a) electrostatic interactions within and between the aggregates and (b) excluded volume effects induced by the neutral additives. Mono- or divalent salts enhance the stability of the N phase when the concentration of LCLCs and salts is small, while they suppress the mesophases when the concentration of LCLCs and salts is large. The addition of non-ionic additives such as PEG to the SSY solution leads to phase-separation into a condensed liquid crystalline (LC) region with a high concentration of SSY and a PEG-rich isotropic region. In the condensed LC region, the distance between the SSY aggregates decreases and the average length of the aggregates increases when the concentration of PEG increases. This dissertation also describes a potential application of LCLCs as a functional material for nanofabrication, namely, a controlled and reversible assembly of gold nanorods. The anisotropic electrostatic interaction between the metallic NRs and chromonic stacks allows one to achieve either side-by-side or end-to-end assembly, depending on the surface charge of the NRs. The assembly of NRs can be controlled by a number of factors influencing the self-assembly of chromonic materials, such as the concentration and pH of the solution. We hope that these studies provide a basic understanding of phase behavior and the physical properties of the reversible self-assembled chromonic materials and expand the opportunities for practical applications of LCLCs.
Download or read book Lyotropic Chromonic Liquid Crystals written by Shuang Zhou and published by Springer. This book was released on 2017-02-14 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis describes lyotropic chromonic liquid crystals (LCLCs) with exotic elastic and viscous properties. The first part of the thesis presents a thorough analysis of the elastic and viscous properties of LCLCs as functions of concentration, temperature and ionic contents, while the second part explores an active nematic system: living liquid crystals, which represent a combination of LCLC and living bacteria. LCLCs are an emerging class of liquid crystals that have shown profound connections to biological systems in two aspects. First, the assembly process of the chromonic aggregates is essentially the same as DNA oligomers and other super-molecular assemblies of biological origin. LCLCs thus provide an excellent model system for studying physical properties such as the elasticity and viscosity of these supramolecular assemblies. Second, LCLCs are biocompatible, thus serving as a unique anisotropic matrix to interface with living systems such as bacteria. This thesis deepens our understanding of both aspects. The noncovalent nature of chromonic aggregation produces the unique viscoelasticity to be found in LCLCs, which differs dramatically from that of traditional LCs. Anisotropic interactions between LCLCs and bacteria lead to fascinating phenomena such as the deformation of LCLCs with a characteristic wavelength determined by the elasticity of the LCLCs and the activity of the bacteria, orientationally controlled trajectories of bacteria and visualization of 24 nm flagella motion.
Download or read book Liquid Crystals written by Tommaso Bellini and published by Springer Science & Business Media. This book was released on 2012-01-21 with total page 419 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fluorinated Liquid Crystals: Design of Soft Nanostructures and Increased Complexity of Self-Assembly by Perfluorinated Segments, by Carsten Tschierske Liquid Crystalline Crown Ethers, by Martin Kaller and Sabine Laschat Star-Shaped Mesogens – Hekates: The Most Basic Star Structure with Three Branches, by Matthias Lehmann DNA-Based Soft Phases, by Tommaso Bellini, Roberto Cerbino and Giuliano Zanchetta Polar and Apolar Columnar Phases Made of Bent-Core Mesogens, by N. Vaupotič, D. Pociecha and E. Gorecka Spontaneous Achiral Symmetry Breaking in Liquid Crystalline Phases, by H. Takezoe Nanoparticles in Liquid Crystals and Liquid Crystalline Nanoparticles, by Oana Stamatoiu, Javad Mirzaei, Xiang Feng and Torsten Hegmann Stimuli-Responsive Photoluminescent Liquid Crystals, by Shogo Yamane, Kana Tanabe, Yoshimitsu Sagara and Takashi Kato
Download or read book Self Assembled Supramolecular Architectures written by Nissim Garti and published by John Wiley & Sons. This book was released on 2012-08-15 with total page 503 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book will describe fundamentals and recent developments in the area of Self-Assembled Supramolecular Architecture and their relevance to the understanding of the functionality of membranes as delivery systems for active ingredients. As the heirarchial architectures determine their performance capabilities, attention will be paid to theoretical and design aspects related to the construction of lyotropic liquid crystals: mesophases such as lamellar, hexagonal, cubic, sponge phase micellosomes. The book will bring to the reader mechanistic aspects, compositional considerations, transition within phases, solubilization capacities, drug entrapment and release mechanisms and transmembrane, transdermal, and other transport phenomena. It will stress the importance of these mesostructures to crystallization and polymorphism of drugs, fats, and nutraceuticals and will discuss regioselectivity of organic and enzymatic reactions that take place at interfaces and within the channels of the mesophase. The book will bring studies on the use of these mesophase as crystallization or particulation media for the formation of nanoparticles and nanocrystals. Chapters will discuss applications in the areas of pharmaceuticals, food, cosmetics, plastics, paper, agro-chemistry and industrial applications.
Download or read book Lyotropic Liquid Crystals written by Ingo Dierking and published by Oxford University Press. This book was released on 2024-07-16 with total page 225 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book aims to review the field of lyotropic liquid crystals from amphiphilic to colloidal systems, bridging the gap between the two worlds of lyotropics and thermotropics by showing that many of the features observed in standard thermotropic liquid crystals may also be observed in lyotropic systems and vice versa. Indeed, for a long time, lyotropic liquid crystals have been overshadowed by their thermotropic counterparts, mainly due to the potential for application of the latter in the display industry. This picture has somewhat shifted over the last decade, with numerous novel lyotropic systems having been discovered and formulated, bringing to light their importance in wider scientific research. For example, the understanding of viruses forming self-assembled ordered phases has largely increased as mineral liquid crystals and clays have experienced a renaissance leading to fundamental research and work on structure formation in nanotechnology. Similarly, nano-rods, nano-wires, nanotubes and 2D materials like graphene oxide and others have been shown to exhibit liquid crystalline behaviour, which may be exploited in self-assembly, drug delivery or biosensors. Cellulose nanocrystals have become an important and popular field of research. The self-assembly of short chain DNA fragments has led to liquid crystal behaviour previously thought to be impossible. Chromonics were shown to exhibit fascinating physical properties, and the combination of active fluids with liquid crystals has opened a whole new field of research to be explored - 'living liquid crystals'.
Download or read book New Trends in Lyotropic Liquid Crystals written by Ingo Dierking and published by MDPI. This book was released on 2020-11-02 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: Liquid crystals (LCs) were discovered more than a century ago, and were, for a long time, treated as a physical curiosity, until the development of flat panel screens and display devices caused a revolution in the information display industry, and in fact in society. There would be no mobile phones without liquid crystals, no flat screen TVs or computer monitors, no virtual reality, just to name a few of the applications that have changed our whole world of vision and perception. All of these inventions are based on liquid crystals that are formed through a change in temperature, thermotropic LCs. However, there is another form of liquid crystals, described even earlier, yet much less talked about; the lyotropic liquid crystals that occur through the change of concentration of some molecules in a solvent. These are found in abundance in nature, making up the cell membranes, and are used extensively in the food, detergents and cosmetics industries. In this collection of articles by experts in their respective research areas, we bring together some of the most recent and innovative aspects of lyotropic liquid crystals, which we believe will drive future research and set novel trends in this field.
Download or read book Formation of Lyotropic Liquid Crystals Through the Self assembly of Bile Acid Building Blocks written by Karan Tamhane and published by . This book was released on 2009 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt: Liquid crystalline materials (LCMs) have gained much popularity over the past century. The thermotropic forms of these materials have been extensively studied and employed in a range of innovative applications. The lyotropic liquid crystal systems that have been studied in the past have often been formed by the organization of natural and synthetic small molecules in solutions. In this study, we use self-assembled supramolecular structures as building blocks to fabricate lyotropic liquid crystals. We investigate the self-assembly of a naturally occurring bile acid called lithocholic acid (LCA), to form supramolecular fibrous and tubular structures in basic aqueous solutions. We control the morphology of the self-assembled structures by manipulating experimental parameters in order to gain comprehensive knowledge regarding the self-assembly process. We characterize these structures with respect to their morphology i.e. their length, diameter, flexibility and shape using atomic force microscopy, optical microscopy and infrared spectroscopy. We produce lyotropic liquid crystal phases using self-assembled LCA structures through modification of physical parameters such as concentration, temperature, shear and pH. The nature of the lyotropic liquid crystal phases depends upon the morphology of the fibers and tubes. We observe that the short, rigid fibers and tubes form nematic phases while long, flexible fibers and tubes form cholesteric phases. We also study the phase transitions of the liquid crystal (LC) phases by observing their patterns using a polarizing microscope. Observations show that LC phases form in samples with LCA concentration above 0.75%w/w. Since the process of self-assembly is time-dependent, so is the formation of liquid crystal phases. We note that the optimum LCA concentration for LC phase formation is 2%-4%w/w and that the liquid crystal transition temperature is about 70°C.
Download or read book Liquid Crystals Beyond Displays written by Quan Li and published by John Wiley & Sons. This book was released on 2012-04-25 with total page 598 pages. Available in PDF, EPUB and Kindle. Book excerpt: The chemistry, physics, and applications of liquid crystals beyond LCDs Liquid Crystals (LCs) combine order and mobility on a molecular and supramolecular level. But while these remarkable states of matter are most commonly associated with visual display technologies, they have important applications for a variety of other fields as well. Liquid Crystals Beyond Displays: Chemistry, Physics, and Applications considers these, bringing together cutting-edge research from some of the most promising areas of LC science. Featuring contributions from respected researchers from around the globe, this edited volume emphasizes the chemistry, physics, and applications of LCs in areas such as photovoltaics, light-emitting diodes, filed-effect transistors, lasers, molecular motors, nanophotonics and biosensors. Specific chapters look at magnetic LCs, lyotropic chromonic LCs, LC-based chemical sensors, LCs in metamaterials, and much more. Introducing readers to the fundamentals of LC science through the use of illustrative examples, Liquid Crystals Beyond Displays covers not only the most recent research in the myriad areas in which LCs are being utilized, but also looks ahead, addressing potential future developments. Designed for physicists, chemists, engineers, and biologists working in academia or industry, as well as graduate students specializing in LC technology, this is the first book to consider LC applications across a wide range of fields.
Download or read book Atomistic Modelling of Structure and Dynamics of Pure Blends and Doped Chromonic Solutions written by Oscar Matus Rivas and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Lyotropic chromonic liquid crystals are an emerging class of mesogenic materials under current intense research and development due to their exceptional phase properties and promising advanced materials and devices’ applications. Although remarkable progress has been achieved in characterizing chromonic phases, a comprehensive understanding of the underlying mechanisms governing their spontaneous self-assembly and aggregation, miscibility capabilities and phase properties is still not entirely understood at the atomistic scale. These challenges arise from the inherent difficulty of characterizing chromonic behaviour at the molecular level with traditional experimental methods. This thesis aims to evaluate and characterize the structural and dynamical properties of relevant pure, blends, and doped chromonic liquid crystal solutions prepared with Disodium Cromoglycate, Sunset Yellow, and Bordeaux dye mesogens using atomistic molecular dynamics simulations. The relationship between equilibrium stacking structure and chromonic molecular architecture is examined, resolved and explained in detail. The formation of structured water around chromonic columnar aggregates via hydrogen bonding interactions and its crucial dynamic role on the aggregation and stability of chromonic mesogens are rigorously investigated. Additionally, molecular mixing affinity rules are determined for binary chromonic blends. Finally, the influence of doping agents, such as NaCl and MgCl2 ionic salts and L-alanine amino acid chiral additive, on the structure and dynamics of chromonic solutions is evaluated. Taken together, the results presented throughout this work provide an in-depth description of the atomistic-level mechanisms controlling the self-assembly and phase properties of lyotropic chromonic liquid crystal solutions, in addition to insights for the development of future experimental and simulation methodologies for expanding chromonics research and applications. These findings represent substantial contributions to the fundamental understanding of chromonic aggregation rules, which are crucial for the fabrication of innovative chromonic functionalities based on the fine-tuning of noncovalent interactions by designing novel custom-made chromonic mesogens"--
Download or read book Liquid Crystals written by Pawel Pieranski and published by John Wiley & Sons. This book was released on 2021-08-31 with total page 370 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book on liquid crystals reports on the new perspectives that have been brought about by the recent expansion of frontiers and overhaul of common beliefs. First, it explores the interaction of light with mesophases, when the light or matter is endowed with topological defects. It goes on to show how electrophoresis, electro-osmosis and the swimming of flagellated bacteria are affected by the anisotropic properties of liquid crystals. It also reports on the recent progress in the understanding of thermomechanical and thermohydrodynamical effects in cholesterics and deformed nematics and refutes the common belief that these effects could explain Lehmann’s observations of the rotation of cholesteric droplets subjected to a temperature gradient. It then studies the physics of the dowser texture, which has remarkable properties. This is of particular interest in regards to nematic monopoles, which can easily be generated, set into motion and collided within it. Finally, this book deals with the spontaneous emergence of chirality in nematics made of achiral molecules, and provides a brief historical context of chirality
Download or read book Self Assembling Systems written by Li-Tang Yan and published by John Wiley & Sons. This book was released on 2016-10-06 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides comprehensive knowledge on concepts, theoretical methods and state-of-the-art computational techniques for the simulation of self-assembling systems Looks at the field of self-assembly from a theoretical perspective Highlights the importance of theoretical studies and tailored computer simulations to support the design of new self-assembling materials with useful properties Divided into three parts covering the basic principles of self-assembly, methodology, and emerging topics
Download or read book Materials Nanoarchitectonics written by Katsuhiko Ariga and published by Elsevier. This book was released on 2023-12-15 with total page 648 pages. Available in PDF, EPUB and Kindle. Book excerpt: Materials Nanoarchitectonics: From Integrated Molecular Systems to Advanced Devices provides the latest information on the design and molecular manipulation of self-organized hierarchically structured systems using tailor-made nanoscale materials as structural and functional units. The book is organized into three main sections that focus on molecular design of building blocks and hybrid materials, formation of nanostructures, and applications and devices. Bringing together emerging materials, synthetic aspects, nanostructure strategies, and applications, the book aims to support further progress, by offering different perspectives and a strong interdisciplinary approach to this rapidly growing area of innovation. This is an extremely valuable resource for researchers, advanced students, and scientists in industry, with an interest in nanoarchitectonics, nanostructures, and nanomaterials, or across the areas of nanotechnology, chemistry, surface science, polymer science, electrical engineering, physics, chemical engineering, and materials science. Offers a nanoarchitectonic perspective on emerging fields, such as metal-organic frameworks, porous polymer materials, or biomimetic nanostructures Discusses different approaches to utilizing "soft chemistry" as a source for hierarchically organized materials Offers an interdisciplinary approach to the design and construction of integrated chemical nano systems Discusses novel approaches towards the creation of complex multiscale architectures
Download or read book Liquid Crystalline Polymers written by Vijay Kumar Thakur and published by Springer. This book was released on 2015-11-16 with total page 627 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces anisotropic innovations in liquid crystalline polymers as well as new nanocomposite materials and testing techniques. The authors detail the newest discoveries of material properties, material types and phases, and material characterization. This interdisciplinary work creates valuable links that strengthen the approach to the evolving field of liquid crystalline polymers/ materials.
Download or read book Liquid Crystals With Nano And Microparticles In 2 Volumes written by Jan P F Lagerwall and published by World Scientific. This book was released on 2016-10-10 with total page 944 pages. Available in PDF, EPUB and Kindle. Book excerpt: 'The overall book content is excellently coordinated to form a synchronised story, interesting to a broad scientific audience … The book summarises the present knowledge in the field, introduces fundamental concepts to the beginners, describes key measuring methods and presents several different typical demonstrative systems, some of them exhibiting an extraordinary rich spectrum of structures and superstructures. I am sure that with time the book will become an attractor to a broad audience (physicists, chemists, material scientists, engineers, etc.), ranging from students, beginners in the field to experienced researchers. To summarise, this is the book that I have been missing on my bookshelf.'Liquid Crystals TodayWhile liquid crystals are today widely known for their successful application in flat panel displays (LCDs), academic liquid crystal research is more and more targeting situations where these anisotropic fluids are put to completely different use, in varying contexts. A particularly strong focus is on colloidal liquid crystals, where particles, bubbles or drops are dispersed in a liquid crystal phase. The liquid crystal can act as a host phase, with the inclusions constituting foreign guests that disturb the local order in interesting ways, often resulting in large-scale positional arrangement and/or uniform alignment of the guests. But it may also be formed by solid particles themselves, if these are of nanoscale dimensions and of disc- or rod-shape, and if they are suspended in an isotropic liquid host at sufficient concentration.This book aims to cover both the modern research tracks, gathering pioneering researchers of the different subfields to give a concise overview of the basis as well as the prospects of their respective specialties. The scope spans from curiosity-driven fundamental scientific research to applied sciences. Over the course of the next decade, the former is likely to generate new tracks of the latter type, considering the exploratory and productive phase of this young research field.
Download or read book Fluids Colloids and Soft Materials written by Alberto Fernandez-Nieves and published by John Wiley & Sons. This book was released on 2016-05-09 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a compilation of self-contained chapters covering a wide range of topics within the broad field of soft condensed matter. Each chapter starts with basic definitions to bring the reader up-to-date on the topic at hand, describing how to use fluid flows to generate soft materials of high value either for applications or for basic research. Coverage includes topics related to colloidal suspensions and soft materials and how they differ in behavior, along with a roadmap for researchers on how to use soft materials to study relevant physics questions related to geometrical frustration.
Download or read book Discotic Liquid Crystals Through Molecular Self assembly written by Changqing Yang and published by . This book was released on 1995 with total page 390 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Soft Matter Physics written by Maurice Kleman and published by Springer Science & Business Media. This book was released on 2007-05-28 with total page 659 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of "soft matter" materials with complex properties has raised a number of interesting problems in basic physics, biology, and materials science, all of which promise new and important technological applications. After a review of chemical bonds and phase transitions, the authors treat topics such as surface phenomena, stability of colloidal systems, structural properties of polymers, and topological defects. The monograph's emphasis on underlying physical principles offers a coherent treatment of the great variety of research in the field.
