Download or read book Photoresponsive Polymers I written by Seth Marder and published by Springer Science & Business Media. This book was released on 2008-08-27 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: With contributions by numerous experts

Download or read book Proceedings of the First International Workshop on Optical Power Limiting written by Francois Kajzar and published by CRC Press. This book was released on 1999 with total page 572 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Design Synthesis and Characterization of New Two photon Absorbing 2PA Fluorescent Dyes and Bioconjugates and Their Applications in Bioimaging written by Carolina D. Andrade and published by . This book was released on 2010 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt: The development of new multiphoton absorbing materials has attracted the attention of researchers for the last two decades. The advantages that multiphoton absorbing materials offer, versus their one-photon absorbing counterparts, rely on the nature of the nonlinearity of the absorption process, where two photons are absorbed simultaneously offering increased 3D resolution, deeper penetration, and less photobleaching and photodamage as a result of a more confined excitation. The applications of efficient two-photon absorbing materials have been extensively expanding into the fields of photodynamic therapy, microscopy, and optical data storage. One of the fields where an increased interest in multiphoton absorbing materials has been most evident is in bioimaging, in particular, when different cellular processes and organelles need to be studied by fluorescence microscopy. The goal of this research was to develop efficient two-photon absorption (2PA) compounds to be used in fluorescence bioimaging, meaning that such compounds need to posses good optical properties, such as high fluorescence quantum yield, 2PA cross section, and photostability. In the first chapter of this dissertation, we describe the synthesis and structural characterization of a new series of fluorescent donor-acceptor and acceptor-acceptor molecules based on the fluorenyl ring system that incorporated functionalities such as alkynes and thiophene rings, through efficient Pd-catalyzed Sonogashira and Stille coupling reactions, in order to increase the length of the conjugation in our systems. These new molecules proved to have high two-photon absorption (2PA), and the effect of these functionalities on their 2PA cross section values was evaluated. Finally, their use in two-photon fluorescence microscopy (2PFM) imaging was demonstrated. One of the limitations of the compounds described in Chapter 1 was their poor water solubility; this issue was addressed in Chapter 2. The use of micelles in drug delivery has been shown to be an area of increasing interest over the last decade. In the bioimaging field, it is key to have dye molecules with a high degree of water solubility to enable cells to uptake the dye. By enclosing a hydrophobic dye in Pluronic® F-127 micelles, we developed a system that facilitates the use of 2PA molecules (typically hydrophobic) in biological systems for nonlinear biophotonic applications, specifically to image the lysosomes. Furthermore, we report in this chapter the efficient microwave-assisted synthesis of the dye used in this study. In addition, linear photophysical and photochemical parameters, two-photon absorption (2PA), and superfluorescence properties of the dye studied in Chapter 2, were investigated in Chapter 3. The steady-state absorption, fluorescence, and excitation anisotropy spectra of this dye were measured in several organic solvents and aqueous media. In Chapter 4, we describe the preparation and the use of an efficient and novel two-photon absorbing fluorescent probe conjugated to an antibody that confers selectivity towards the vascular endothelial growth factor receptor 2 (VEGFR-2) in porcine aortic endothelial cells that express this receptor (PAE-KDR). It is known that this receptor is overexpressed in certain cancer processes. Thus, targeting of this receptor will be useful to image the tumor vasculature. It was observed that when the dye was incubated with cells that do not express the receptor, no effective binding between the bioconjugate and the cells took place, resulting in very poor, nonspecific fluorescence images by both one and two-photon excitation. On the other hand, when the dye was incubated with cells that expressed VEGFR-2, efficient imaging of the cells was obtained, even at very low concentrations (0.4[micrometer]). Moreover, incubation of the bioconjugate with tissue facilitated successful imaging of vasculature in mouse embryonic tissue.

Download or read book Development of Novel Two Photon Absorbing Chromophores written by and published by . This book was released on 2006 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: There has been much interest in the development of two-photon absorbing materials and many efforts to understand the nonlinear absorption properties of these dyes, but this area is still not well understood. A computational model has been developed in our lab to understand the nanosecond nonlinear absorption properties that incorporate all of the measured one-photon photophysical parameters of a class of materials called AFX. We have investigated the nonlinear and the photophysical properties of the AFX chromophores including the two-photon absorption cross-section, the excited state cross-section, the intersystem crossing quantum yield, and the singlet and triplet excited state lifetimes using a variety of experimental techniques that include UV-visible, fluorescence and phosphorescence spectroscopy, time correlated single photon counting, ultrafast transient absorption, and nanosecond laser flash photolysis. The model accurately predicts the nanosecond nonlinear transmittance data using experimentally measured parameters.

Download or read book Applications and Synthesis of Two photon Absorption Materials for Biological Imaging written by Xiaopeng Wang and published by . This book was released on 2000 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Two Photon Absorption Materials written by Jun Kawamata and published by Pan Stanford Publishing. This book was released on 2015-12-31 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes effective strategies for designing efficient two-photon absorption compounds. Not only experimental examples but also recent progresses in theoretical aspect are described. Furthermore, specific design strategies of compounds for important applications, data storage and biological imaging, are described.

Download or read book Enhanced Two photon Absorption in a Squaraine fluorene squaraine Dye written by William V. Moreshead and published by . This book was released on 2013 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: The discovery of any new technology is usually accompanied by a need for new or improved materials which make that technology useful in practical applications. In the case of two-photon absorption (2PA) this has truly been the case. Since its first demonstration in 1961, there has been an ever increasing quest to understand the relationships between two-photon absorption and the structure of two-photon absorbing materials. This quest has been motivated by the many applications for 2PA which have been reported, including fluorescence bioimaging, 3D microfabrication, 3D optical data storage, upconverted lasing, and photodynamic therapy. The work presented in this dissertation represents another step in the effort to better understand the structure/property relationships of 2PA. In this work a new, squaraine-fluorene-squaraine molecule, proposed through a joint effort of quantum and synthetic chemists, was synthesized and its photophysical properties were measured. The measurements included linear and two-photon photophysical properties, as well as solvatochromic behavior. Quantum calculations were done to aid in understanding those photophysical and solvatochromic properties. A single squaraine dye was also synthesized and used as a model compound to assist in understanding this new structure. In Chapter 1 an introduction to 2PA and several of its applications is given. Chapter 2 gives a background of 2PA structure/property relationships that have been reported to date, based on work done with polymethine dyes. Chapter 3 gives a full account of the synthesis, characterization, and detailed quantum chemical analyses of this new squaraine-fluorene-squaraine molecule and the corresponding model compound squaraine dye. Chapter 4 gives some additional work and suggested future directions.

Download or read book Design Synthesis and Characterization of Organic and Polymeric Two photon Absorbing Materials written by Lixin Zheng and published by . This book was released on 2003 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Optically Induced Nanostructures written by Karsten König and published by Walter de Gruyter GmbH & Co KG. This book was released on 2015-05-19 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanostructuring of materials is a task at the heart of many modern disciplines in mechanical engineering, as well as optics, electronics, and the life sciences. This book includes an introduction to the relevant nonlinear optical processes associated with very short laser pulses for the generation of structures far below the classical optical diffraction limit of about 200 nanometers as well as coverage of state-of-the-art technical and biomedical applications. These applications include silicon and glass wafer processing, production of nanowires, laser transfection and cell reprogramming, optical cleaning, surface treatments of implants, nanowires, 3D nanoprinting, STED lithography, friction modification, and integrated optics. The book highlights also the use of modern femtosecond laser microscopes and nanoscopes as novel nanoprocessing tools.

Download or read book Three Dimensional Microfabrication Using Two Photon Polymerization written by Tommaso Baldacchini and published by William Andrew. This book was released on 2019-10-31 with total page 766 pages. Available in PDF, EPUB and Kindle. Book excerpt: Three-Dimensional Microfabrication Using Two-Photon Polymerization, Second Edition offers a comprehensive guide to TPP microfabrication and a unified description of TPP microfabrication across disciplines. It offers in-depth discussion and analysis of all aspects of TPP, including the necessary background, pros and cons of TPP microfabrication, material selection, equipment, processes and characterization. Current and future applications are covered, along with case studies that illustrate the book's concepts. This new edition includes updated chapters on metrology, synthesis and the characterization of photoinitiators used in TPP, negative- and positive-tone photoresists, and nonlinear optical characterization of polymers. This is an important resource that will be useful for scientists involved in microfabrication, generation of micro- and nano-patterns and micromachining. Discusses the major types of nanomaterials used in the agriculture and forestry sectors, exploring how their properties make them effective for specific applications Explores the design, fabrication, characterization and applications of nanomaterials for new Agri-products Offers an overview of regulatory aspects regarding the use of nanomaterials for agriculture and forestry

Download or read book Factories of the Future written by Tullio Tolio and published by Springer. This book was released on 2019-02-14 with total page 494 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is open access under a CC BY 4.0 license.This book presents results relevant in the manufacturing research field, that are mainly aimed at closing the gap between the academic investigation and the industrial application, in collaboration with manufacturing companies. Several hardware and software prototypes represent the key outcome of the scientific contributions that can be grouped into five main areas, representing different perspectives of the factory domain:1) Evolutionary and reconfigurable factories to cope with dynamic production contexts characterized by evolving demand and technologies, products and processes.2) Factories for sustainable production, asking for energy efficiency, low environmental impact products and processes, new de-production logics, sustainable logistics.3) Factories for the People who need new kinds of interactions between production processes, machines, and human beings to offer a more comfortable and stimulating working environment.4) Factories for customized products that will be more and more tailored to the final user’s needs and sold at cost-effective prices.5) High performance factories to yield the due production while minimizing the inefficiencies caused by failures, management problems, maintenance.This books is primarily targeted to academic researchers and industrial practitioners in the manufacturing domain.

Download or read book Multiphoton Absorption and Nonlinear Transmission Processes written by Kevin D. Belfield and published by SPIE-International Society for Optical Engineering. This book was released on 2003 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Physics Of Nonlinear Optics written by Guang S He and published by World Scientific Publishing Company. This book was released on 1999-12-29 with total page 576 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nonlinear optics has been a rapidly growing field in recent decades. It is based on the study of effects and phenomena related to the interaction of intense coherent light radiation with matter.Physics of Nonlinear Optics describes various major nonlinear optical effects, including physical principles, experimental techniques, up-to-date research achievements, and current or potential applications. This book features clear conceptual descriptions, concise formulations, and emphasizes both theoretical and experimental aspects of nonlinear optics. The readability of this book is particularly enhanced by a series of color photographs showing the spectacular appearances of various nonlinear optical effects.Both authors of this book are outstanding research scientists renowned in their professional areas. Their major research achievements in nonlinear optics include the pioneering studies of two-wave-coupled refractive-index change, Raman-enhanced self-focusing, optical-frequency Pockels effect, stimulated Kerr scattering, optical phase-conjugation via backward stimulated emission, and two-photon-absorption based optical limiting, stabilization and reshaping.

Download or read book Two photon Induced Photochemistry written by Jing Wang and published by . This book was released on 2007 with total page 596 pages. Available in PDF, EPUB and Kindle. Book excerpt: Two-photon absorption is the process in which a molecule absorbs two photons simultaneously. The two key advantages of two-photon processes over one-photon processes are the possibility of excitation of materials with high three-dimensional spatial resolution and deep light-penetration into absorbing materials. Based on bond-cleavage reactions activated by photon-induced intramolecular electron transfer, two-photon activatable acid and radical initiators and two-photon removable protecting groups have been successfully designed and synthesized for photopolymerization and three-dimensional microfabrication and for biomedical photo-triggers. The optical and chemical properties of synthesized molecules, such as quantum yield of acid generation, initiation efficiency of photopolymerization, and photolysis efficiency, have been studied by using a variety of physical and analytical techniques under one-photon conditions. The two-photon characteristics and applications of these molecules are being investigated in collaboration with other groups.

Download or read book Ultrafast Two photon Absorption in Organic Molecules written by Nikolay Sergeevich Makarov and published by . This book was released on 2010 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation explores quantitative two-photon absorption spectroscopy to relate molecular structure with optical properties of organic chromophores. The dissertation describes an advanced fluorescence-based technique for reliable measurements of the two-photon spectra and cross sections. To facilitate the measurements it establishes a set of reference compounds measured with a 15% absolute accuracy covering a broad range of excitation and fluorescence wavelengths. The dissertation shows that in many cases the few-essential-levels model can be successfully applied for the description and interpretation of two-photon absorption spectra and cross sections, at least for the low-energy transitions. The dissertation presents examples of applications of two-photon absorption for volumetric optical storage and cancer tumor detection. It describes the basic principles of the two-photon absorption-based optical memory and limitations imposed on two-photon sensitivity of photochromic materials by a necessity of fast access to the data. It also proposes a novel technique for sensitive detection of cancer cells by using two-photon excitation of near-IR fluorescence of a commercial dye and discusses the mechanisms responsible for differentiation between the normal and the cancer cells. The methods described in this dissertation can be applied to understanding the relations between structure and two-photon absorption strength of individual transitions of organic and biological chromophores, which can be used for design of new materials, maximally adapted for particular applications.

Download or read book DURIP97 Instrumentation for Characterization of Two Photon Absorbing Organic Materials written by Seith Marder and published by . This book was released on 1998 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: DURIP funds were used to purchase a Spex Model FL112 High Performance Research Grade Fluorimeter and a Nd:YAG-pumped nanosecond Optical Parametric Oscillator Laser System with tunability from 440 nm - 1800 nm. This equipment was used to measure the two-photon absorption spectra for a variety of molecules from different classes and identify promising candidate molecules to meet DoD requirements for a variety of applications. A strategy for the design of molecules with large two-photon absorption cross sections has been developed. The strategy is based on the concept that symmetric charge transfer, from the ends of a conjugated system to the middle, or vice versa, upon excitation is correlated to enhanced two-photon absorption cross sections. It was shown that newly synthesized bis-styrylbenzene derivatives with donor-acceptor-donor, and acceptor-donor-acceptor structural motifs exhibit exceptionally large two-photon absorption cross sections, up to roughly 400 times that of trans-stilbene.

Download or read book Absolute Two Photon Absorption Coefficients in UltraViolet Window Materials written by N. Bloembergen and published by . This book was released on 1977 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt: The absolute two-photon absorption coefficients of u.v. transmitting materials have been measured using well-calibrated single picosecond pulses, at the third and fourth harmonic of a mode locked Nd:YAG laser systems. Two-photon absorption coefficients of the order of .001 cm/MW were measured for alkali-halides, and .0001 cm/MW for harmonic generating crystals. In materials with band gap greater than 2 h-bar omega, no nonlinear absorption could be observed. Calculations based on the Keldysh theory with one adjustable parameter agree quite well with the experimentally observed dispersions in the two-photon absorption coefficients. The effect of multi-photon absorption on the conversion efficiency of harmonic generating crystals and on the breakdown of u.v. window materials is also discussed. (Author).