Download or read book Designed Functional Defects in Colloidal Photonic Crystals Switching Biomonitoring and Modified Photoluminescence written by and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Two complementary bottom-up approaches are presented for the controlled incorporation of "smart" planar defects into self-assembled colloidal photonic crystals (CPCs). The defect layer is based on a functional nanometer scaled thin film that is either prepared by layer-by-layer self-assembly and microcontact transfer printing or by spin-coating and sacrificial CPC infiltration. The developed methods allow for the integration of designed defect thin films from a huge variety of chemically diverse materials and can be employed at low-cost and large-scale. Optical spectra show a sharp transmission state within the photonic stop band, induced by the defect. The position of the defect wavelength is dependent on the optical thickness of the defect layer. Active tuning of the intragap defect state is performed by preparing defect layers from macromolecules responsive to external stimuli such as light, temperature, redox-cycling and mechanical pressure. The studies are supported by independently performed ellipsometry measurements and theoretical scalar wave approximation calculations. In addition, CPCs with functional biomolecular planar defects are presented. Through shifts of the defect mode, DNA conformational changes, the enantioselective intercalation of a chiral anti-cancer drug and enzyme activities are optically monitored. Incorporation of fluorescent dyes and quantum dots into defect CPCs leads to a clear modification of the photoluminescence (PL) spectra by photonic stopband and defect state. Switchable PL modification is detected when employing addressable defect CPCs.
Download or read book Chemically Tunable Colloidal Photonic Crystals written by André C. Arsenault and published by . This book was released on 2007 with total page 370 pages. Available in PDF, EPUB and Kindle. Book excerpt: Photonic crystals are a novel class of materials which experience a spatially periodic modulation in their refractive index. A periodicity at the length scale of the wavelength of photons can exert an exquisite control over the flow of light passing through these materials. In this thesis I explore colloidal photonic crystals fabricated through bottom-up self-assembly techniques, and probe how their properties can be tuned through chemical means.The next section of my thesis describes the synthesis and properties of porous and elastic photonic crystals. These materials can be compressed with small forces, generating concomitant changes in optical properties. This mechanical response was used to image microstructured stamps as well as human fingerprints. The porous framework of the material, on the other hand, was used to house luminescent nanoclusters. The interplay of photoluminescence and the modified photonic density of states due to the photonic crystal resulted in highly tunable light emission.The thesis follows with a section on "smart" planar defects within colloidal photonic crystals. The defects are synthesized by layer-by-layer electrostatic self-assembly, a method with incredible compositional diversity. Sensors could thus be created, responsive to organic vapors, light, temperature, redox agents, and biochemically relevant molecules such as DNA.The final section of my thesis explores the use of colloidal photonic crystal templates for confined self-assembly processes. I first looked at polyelectrolyte self-assembly in these confines, and found a dramatic influence on the deposition process. I then looked at block copolymer self-assembly in these spaces, and found that the proximity of interfaces in the structure could generate unprecedented nanostructures.The first section of my thesis deals with metallopolymer-based swellable photonic crystals. Exposure to stimuli such as solvents, vapors, and redox agents can affect the volume of the metallopolymer component and modulate reflected colors from the photonic crystal. In addition, the redox-activity of these materials has allowed their incorporation into electrochemical cells which could form the basis of next generation color displays.
Download or read book Intrinsic and Extrinsic Defects in Colloidal Photonic Crystal Films written by Evangellos William Vekris and published by . This book was released on 2007 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt: Photonic crystals (PC's) are a new class of engineered material that is structurally periodic on the scale of optical wavelengths. One promising form of photonic crystal is the self-assembled colloidal crystal film, which consist of a close-packed lattice of colloidal spheres and can be grown inexpensively from a colloidal dispersion. This crystal can serve as a template for the infiltration of a material of higher refractive index, such as silicon, to create a material possessing a complete photonic bandgap (PBG). However, the self-assembled nature of colloidal crystal films allows the formation of intrinsic defects. Such defects, disruptions in the lattice periodicity, can be expected to influence the optical properties of this photonic material. Here, various intrinsically-formed defects are structurally analyzed by microscopy, and their optical properties are then individually measured through careful spatially-resolved optical spectroscopy. Point, line, and volume defects are shown to contribute to incoherent scattering, in good agreement with numerical simulation. In all cases, the influence of such defects on the fundamental stop-band is negligible, while influences on the "higher-band" region of the bandstructure and the PBG are shown to be significant. Stacking faults, variations in the stacking of close-packed crystalline planes, are also analysed. It is shown that different stacking sequences give rise to unique optical spectra, which are shown to differ in the higher-band region of the bandstructure, while leaving the fundamental stopgap unaffected. Additionally, stacking faults are shown to be caused by the incorporation of differently-sized impurity spheres in the lattice, a hard- sphere type mechanism analogous to atomic systems. A fabrication method for extrinsic defects, those which are deliberately introduced to create a designed photonic functionality, and which combines top-down photolithographic patterning with bottom-up self-assembly, is presented. Defects created using this technique can potentially serve as optical waveguides in silicon inverse colloidal photonic crystals, with applications in optical telecommunications or optical computing. Through better understanding of the structure, optical properties, and formation mechanisms of colloidal crystal defects, the quality of self-assembled photonic crystal films can be improved, resulting in more homogeneous optical properties and allowing the full-potential of colloidal photonic crystals to be realized.
Download or read book Fabrication and Defect Design in Two dimensional Colloidal Photonic Crystals written by Erik Peter Geiss and published by . This book was released on 2003 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Liquid Crystal Colloids written by Igor Muševič and published by Springer. This book was released on 2017-05-14 with total page 313 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book brings together the many concepts and discoveries in liquid crystal colloids contributed over the last twenty years and scattered across numerous articles and book chapters. It provides both a historical overview of the development of the field and a clear perspective on the future applications in photonics. The book covers all phenomena observed in liquid crystal colloids with an emphasis on experimental tools and applications of topology in condensed matter, as well as practical micro-photonics applications. It includes a number of spectacular manifestations of new topological phenomena not found or difficult to observe in other systems. Starting from the early works on nematic colloids, it explains the basics of topological defects in ordered media, charge and winding, and the elastic forces between colloidal particles in nematics. Following a detailed description of experimental methods, such as optical tweezing and particle tracking, the book eases the reader into the theoretical part, which deals with elastic deformation of nematic liquid crystals due to inclusions and surface alignment. This is discussed in the context of basic mean field Landau-de Gennes Q-tensor theory, with a brief explanation of the free-energy minimization numerical methods. There then follows an excursion into the topology of complex nematic colloidal structures, colloidal entanglement, knotting and linking. Nematic droplets, shells, handlebodies and chiral topological structures are addressed in separate chapters. The book concludes with an extensive chapter on the photonic properties of nematic dispersions, presenting the concept of integrated soft matter photonics and discussing the concepts of nematic and chiral nematic microlasers, surface-sensitive photonic devices and smectic microfibers. The text is complemented by a large bibliography, explanatory sketches and beautiful micrographs.
Download or read book Applications of Liquid Crystals written by G. Meier and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 171 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past ten years liquid crystals have attracted much interest and considerable progress has been made with respect to our knowledge in this field. The recent development was initiated mainly by the work of J. L. Fergason and G. H. Heilmeier, who pointed out the importance of liquid crystals for thermographic and electro optic applications. The first part of this book is a brief introduction to the physics of liquid crystals. The structures and properties of the three basic types of liquid crystals are discussed. A special paragraph is devoted to electric-field effects, which are important in display applications. The chapter on Scientific Applications gives an insight into the potential applications of liquid crystals in fundamental research, with special emphasis on explaining the principles involved. Two groups of potential applications are discussed in detail: 1. the use of liquid crystals as anisotropic solvent for the determination of molecular properties by means of spectroscopy, and 2. their use in analytical chemistry, particularly in gas chromatography. The reverse process involves the use of the dissolved molecules as microscopic probes in the investigation of the dynamical molecular structure of anisotropic fluid systems (e.g. biological membranes). This extremely important technique is also described.
Download or read book Textbook of Nanoscience and Nanotechnology written by B.S. Murty and published by Springer Science & Business Media. This book was released on 2013-12-06 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is meant to serve as a textbook for beginners in the field of nanoscience and nanotechnology. It can also be used as additional reading in this multifaceted area. It covers the entire spectrum of nanoscience and technology: introduction, terminology, historical perspectives of this domain of science, unique and widely differing properties, advances in the various synthesis, consolidation and characterization techniques, applications of nanoscience and technology and emerging materials and technologies.
Download or read book Glucose Sensing written by Chris D. Geddes and published by Springer Science & Business Media. This book was released on 2007-12-29 with total page 460 pages. Available in PDF, EPUB and Kindle. Book excerpt: An essential reference for any laboratory working in the analytical fluorescence glucose sensing field. The increasing importance of these techniques is typified in one emerging area by developing non-invasive and continuous approaches for physiological glucose monitoring. This volume incorporates analytical fluorescence-based glucose sensing reviews, specialized enough to be attractive to professional researchers, yet appealing to a wider audience of scientists in related disciplines of fluorescence.
Download or read book Modern Tools for Time Resolved Luminescence Biosensing and Imaging written by and published by Frontiers Media SA. This book was released on 2021-09-01 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Upconversion Nanophosphors written by Sabu Thomas and published by Elsevier. This book was released on 2021-11-04 with total page 426 pages. Available in PDF, EPUB and Kindle. Book excerpt: Upconversion Nanophosphors provides detailed information about various lanthanide-based upconversion nanoparticles and their application in different fields. It will also help solve fundamental and applied problems of inorganic phosphor materials showing upconversion behavior, as well as generate innovative ideas related to the application of inorganic phosphor materials. This book will prove to be an invaluable reference work for scientists, engineers, industrial experts, and masters and PhD students working in the field of upconversion and materials science. - Covers the synthesis and characterization of upconversion nanophosphors and their applications - Highlights which classes of upconversion materials are suitable for a specific application - Explores processes to engineer upconversion nanoparticles for state-of-the-art technologies, including upconversion labelling and counterfeiting, highly sensitive and selective biosensing, and upconversion-activated drug delivery
Download or read book Superlubricity written by Ali Erdemir and published by Elsevier. This book was released on 2007-03-30 with total page 525 pages. Available in PDF, EPUB and Kindle. Book excerpt: Superlubricity is defined as a sliding regime in which friction or resistance to sliding vanishes. It has been shown that energy can be conserved by further reducing/removing friction in moving mechanical systems and this book includes contributions from world-renowned scientists who address some of the most fundamental research issues in overcoming friction. Superlubricity reviews the latest methods and materials in this area of research that are aimed at removing friction in nano-to-micro scale machines and large scale engineering components. Insight is also given into the atomic-scale origins of friction in general and superlubricity while other chapters focus on experimental and practical aspects or impacts of superlubricity that will be very useful for broader industrial community.* Reviews the latest fundamental research in superlubricity today* Presents 'state-of-the-art' methods, materials, and experimental techniques* Latest developments in tribomaterials, coatings, and lubricants providing superlubricity
Download or read book Nanomaterials for Sustainable Energy written by Quan Li and published by Springer. This book was released on 2016-05-12 with total page 602 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the unique mechanical, electrical, and optical properties of nanomaterials, which play an important role in the recent advances of energy-related applications. Different nanomaterials have been employed in energy saving, generation, harvest, conversion, storage, and transport processes very effectively and efficiently. Recent progress in the preparation, characterization and usage of 1D, 2D nanomaterials and hybrid architectures for energy-related applications and relevant technologies and devices, such as solar cells, thermoelectronics, piezoelectronics, solar water splitting, hydrogen production/storage, fuel cells, batteries, and supercapacitors is covered. Moreover, the book also highlights novel approaches in nanomaterials design and synthesis and evaluating materials sustainability issues. Contributions from active and leading experts regarding important aspects like the synthesis, assembly, and properties of nanomaterials for energy-related applications are compiled into a reference book. As evident from the diverse topics, the book will be very valuable to researchers working in the intersection of physics, chemistry, biology, materials science and engineering. It may set the standard and stimulates future developments in this rapidly emerging fertile frontier of nanomaterials for energy.
Download or read book Brilliant Light in Life and Material Sciences written by Vasili Tsakanov and published by Springer Science & Business Media. This book was released on 2007-03-31 with total page 484 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains an excellent overview of the status and highlights of brilliant light facilities and their applications in biology, chemistry, medicine, materials and environmental sciences. Overview papers on diverse fields of research by leading experts are accompanied by the highlights in the near and long-term perspectives of brilliant X-Ray photon beam usage for fundamental and applied research.
Download or read book Selenium in plants written by Elizabeth A.H. Pilon-Smits and published by Springer. This book was released on 2017-05-10 with total page 326 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers many facets of plant selenium (Se) accumulation: molecular genetics, biochemistry, physiology, and ecological and evolutionary aspects. Broader impacts and applications of plant Se accumulation also receive attention. Plant Se accumulation is very relevant for environmental and human health. Selenium is both essential at low levels and toxic at high levels, and both Se deficiency and toxicity are problems worldwide. Selenium can positively affect crop productivity and nutritional value. Plants may also be used to clean up excess environmental Se. Selenium in plants has profound ecological impact, and likely contributes to Se movement in ecosystems and global Se cycling.
Download or read book Handbook of Smart Textiles written by Xiaoming Tao and published by Springer. This book was released on 2015-10-14 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The “Handbook of Smart Textiles” aims to provide a comprehensive overview in the field of smart textile describing the state of the art in the research sector as well as the well-established techniques applied in industries. The handbook is planned to cover from fundamental theories, experimental techniques, characterization methods, as well as real applications with successful commercialized examples. The book is structured in a way in which it is appropriate for graduate students, PhD candidates, and professionals in diverse scientific and engineering communities devoted to relevant fields, including textile engineering, chemistry, bioengineering, material engineering, mechanical engineering, electrical engineering. The book will also provide a solid reference for industrial players who look for innovative technologies as well as environmental, safety concerns for the development of smart textile related products.
Download or read book Resource Chemistry written by Fang Zhang and published by Academic Press. This book was released on 2021-02-01 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt: Natural resources are under huge pressure due to human population growth and societal change. As a result, rational use of resources and efficient reduction of pollutants have become critical. Chemistry occupies a key position in improving efficiency and reducing pollution. Efficient and environmentally-friendly chemical processes to exploit resources are in demand. Resource Chemistry defines the concepts and principles of resource chemistry and highlights significant advances. The book introduces recent achievements in natural and non-natural resources utilization through chemical science and technology. First, the title describes resource distribution and defines resource chemistry and related chemical methods for resource utilization. It then describes the four main natural resources available for use: energy, minerals, water, and plants. The book considers re-utilization of non-natural resources, such as chemical by-products. Finally, the book considers some future developments and challenges awaiting resource chemistry. The title provides comprehensive coverage of current resource chemistry, as well as mapping the frontiers of this important field. Defines the principles of resource chemistry in environmental context Asks how chemistry can improve resource utilization Highlights the application of chemical processes for natural and non-natural resource utilization Describes recent developments in and maps the frontiers of resource chemistry Takes an interdisciplinary approach, of use to a broad-range of research fields
Download or read book Environmental Engineering Dictionary and Directory written by Thomas M. Pankratz and published by CRC Press. This book was released on 2000-09-22 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: Like most technical disciplines, environmental science and engineering is becoming increasingly specialized. As industry professionals focus on specific environmental subjects they become less familiar with environmental problems and solutions outside their area of expertise. This situation is compounded by the fact that many environmental science
