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Optical properties are among the most fascinating and useful properties of nanomaterials and have been extensively studied using a variety of optical spectroscopic techniques. A basic understanding of the optical properties and related spectroscopic techniques is essential for anyone who is interested in learning about nanomaterials of semiconductors, insulators or metal. This is partly because optical properties are intimately related to other properties and functionalities (e.g. electronic, magnetic, and thermal) that are of fundamental importance to many technological applications, such as energy conversion, chemical analysis, biomedicine, optoelectronics, communication, and radiation detection.

Presents the state of the technology, from fundamentals to new materials and applications Today's electronic devices, computers, solar cells, printing, imaging, copying, and recording technology, to name a few, all owe a debt to our growing understanding of the photophysics and photochemistry of polymeric materials. This book draws together, analyzes, and presents our current understanding of polymer photochemistry and photophysics. In addition to exploring materials, mechanisms, processes, and properties, the handbook also highlights the latest applications in the field and points to new developments on the horizon. Photochemistry and Photophysics of Polymer Materials is divided into seventeen chapters, including: Optical and luminescent properties and applications of metal complex-based polymers Photoinitiators for free radical polymerization reactions Photovoltaic polymer materials Photoimaging and lithographic processes in polymers Photostabilization of polymer materials Photodegradation processes in polymeric materials Each chapter, written by one or more leading experts and pioneers in the field, incorporates all the latest findings and developments as well as the authors' own personal insights and perspectives. References guide readers to the literature for further investigation of individual topics. Together, the contributions represent a series of major developments in the polymer world in which light and its energy have been put to valuable use. Not only does this reference capture our current state of knowledge, but it also provides the foundation for new research and the development of new materials and new applications.

The creation of affordable high speed optical communications using standard semiconductor manufacturing technology is a principal aim of silicon photonics research. This would involve replacing copper connections with optical fibres or waveguides, and electrons with photons. With applications such as telecommunications and information processing, light detection, spectroscopy, holography and robotics, silicon photonics has the potential to revolutionise electronic-only systems. Providing an overview of the physics, technology and device operation of photonic devices using exclusively silicon and related alloys, the book includes: * Basic Properties of Silicon * Quantum Wells, Wires, Dots and Superlattices * Absorption Processes in Semiconductors * Light Emitters in Silicon * Photodetectors, Photodiodes and Phototransistors * Raman Lasers including Raman Scattering * Guided Lightwaves * Planar Waveguide Devices * Fabrication Techniques and Material Systems Silicon Photonics: Fundamentals and Devices outlines the basic principles of operation of devices, the structures of the devices, and offers an insight into state-of-the-art and future developments.

Current concern for soil quality has stimulated research on soil organic matter (OM). Humic substances (HS) of different origin were compared applying ultraviolet-visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), “steady-state” fluorescence spectroscopy, and 13C nuclear magnetic resonance (13C NMR). Sodium humates samples were isolated from soil (Gleyic Luvisol), compost, and South-Moravian lignite from the mine Mír in Mikulčice. Sodium humates (SH) were extracted by a conventional procedure recommended by the International Humic Substances Society (IHSS). Results showed that the presence of O-containing functional groups (carbonyl in aldehydes and ketones, carboxyl in carboxylic acids, ester and ether groups) are in the order of compost > soil > lignohumate > lignite. Further, results of FTIR, fluorescence spectroscopy, and 13C NMR suggested that samples of sodium humates isolated from soil, compost, and lignite were a more polycondensed, oxidized, unsaturated, humified, and aromatic structure. On the other hand, commercial lignohumate (LH) had very simple structural components and wide molecular heterogeneity. Furthermore, a small molecular size and weight, low degree of aromatic polycondensation, low level of conjugated chromophores and fluorophores, and low humification degree were characteristic for commercial LH. It should be noted that the sample of commercial LH was characterized by 13C NMR analysis with a slightly higher value of aromaticity α in comparison with the sample of compost. The application of non-destructive analytical methods such as UV-VIS, FTIR, 13C NMR, and fluorescence spectroscopy help us to provide main characteristics of selected humic substances.

\"...the book does an excellent job of putting together several different classes of materials.Many common points emerge, and the book may facilitate the development of hybrids in which the qualities of the \"parents\" are enhanced.\" -Angew.Chem.Int.Ed.

Light scattering-based methods are used to characterize small particles suspended in water in a wide range of disciplines ranging from oceanography, through medicine, to industry. The scope and accuracy of these methods steadily increases with the progress in light scattering research. This book focuses on the theoretical and experimental foundations of the study and modeling of light scattering by particles in water and critically evaluates the key constraints of light scattering models. It begins with a brief review of the relevant theoretical fundamentals of the interaction of light with condensed matter, followed by an extended discussion of the basic optical properties of pure water and seawater and the physical principles that explain them. The book continues with a discussion of key optical features of the pure water/seawater and the most common components of natural waters. In order to clarify and put in focus some of the basic physical principles and most important features of the experimental data on light scattering by particles in water, the authors employ simple models. The book concludes with extensive critical reviews of the experimental constraints of light scattering models: results of measurements of light scattering and of the key properties of the particles: size distribution, refractive index (composition), structure, and shape. These reviews guide the reader through literature scattered among more than 210 scientific journals and periodicals which represent a wide range of disciplines. A special emphasis is put on the methods of measuring both light scattering and the relevant properties of the particles, because principles of these methods may affect interpretation and applicability of the results. The book includes extensive guides to literature on light scattering data and instrumentation design, as well as on the data for size distributions, refractive indices, and shapes typical of particles in natural waters. It also features a comprehensive index, numerous cross-references, and a reference list with over 1370 entries. An errata sheet for this work can be found at: http://www.tpdsci.com/Ref/Jonasz_M_2007_LightScatE.php *Extensive reference section provides handy compilations of knowledge on the designs of light scattering meters, sources of experimental data, and more *Worked exercises and examples throughout

Los aerosoles de hollín producidos durante procesos de combustión incompleta son aglomerados compuestos por partículas primarias carbonáceas cuasi-esféricas con disposiciones (forma, tamaño, estructura interna) marcadamente diferentes y composición variable. Aunque son uno de los principales contribuyentes al cambio climático, sigue siendo difícil cuantificar con precisión su potencial de calentamiento global (GWP). Sería necesario un conocimiento preciso de las propiedades ópticas de los aglomerados de hollín (carbón negro--BC) para establecer de manera justa un GWP equivalente a C[O.sub.2]. Los efectos de calentamiento del BC dependen de su tamaño y forma, y a pesar de su tiempo de residencia limitado en la atmósfera, su alta fuerza radiativa conduce a GWP ~ 2000. Cuantificar las concentraciones de BC en la atmósfera a menudo se basa en mediciones ópticas, que generalmente carecen de precisión. Nuestros cálculos sobre el forzamiento radiativo directo del BC mostraron que la irregularidad del aglomerado, así como su tamaño, afectan marcadamente su capacidad de enfriamiento/calentamiento debido a las variaciones extremas de sus características de absorción y dispersión. La estimación del forzamiento radiativo incremental de los aerosoles es un desafío, ya que depende de parámetros locales como la nubosidad, el albedo de la superficie, la concentración de aerosoles, etc., los cuales son variables en todo el mundo. En base a eso, no recomendamos utilizar un GWP equivalente a C[O.sub.2] único para el BC. Carbono negro, aglomerados de hollín, GWP, forzamiento radiativo, propiedades ópticas Soot aerosols produced during incomplete combustion processes are agglomerates composed of quasi-spherical carbonaceous primary particles with markedly different arrangements (shape, size, and internal structure) and varying compositions. Although they have been considered to be one of the main contributors to climate change, it remains difficult to quantify their global warming potential (GWP) precisely. Exact knowledge of the optical properties of soot agglomerates (black carbon -BC) would be necessary to fairly establish a C[O.sub.2] equivalent GWP. BC warming effects depend on their size and shape, and despite their limited residence time in the atmosphere, their high radiative forcing would lead to GWP ~ 2000. The quantification of BC concentrations in the atmosphere is often based on optical measurements, which usually lack accuracy. Our calculations on the direct radiative forcing of BC showed that the irregularity of the agglomerate, and their size markedly affect the cooling/heating capacity due to extreme variations of its absorbing and scattering characteristics. In addition, the estimation of the incremental radiative forcing of aerosols is challenging since it is highly dependent on local parameters such as cloudiness, surface albedo, aerosol concentration, etc., which are highly variable worldwide. Based on that, we do not recommend using a unique C[O.sub.2] equivalent GWP for BC. KEYWORDS: Black carbon, soot agglomerates, GWP, radiative forcing, optical properties

This special volume contains the proceedings of the 9th Epioptics Workshop, held at the Ettore Majorana Foundation and Centre for Scientific Culture, Erice, Sicily, from July 20 to 26, 2006. The workshop was the 9th in the Epioptics series and the 39th of the International School of Solid State Physics.

Photosystem II (PS II) efficiency, nonphotochemical fluorescence quenching, and xanthophyll cycle composition were determined in situ in the natural environment at midday in (i) a range of differently angled sun leaves of Euonymus kiautschovicus Loesener and (ii) in sun leaves of a wide range of different plant species, including trees, shrubs, and herbs. Very different degrees of light stress were experienced by these leaves (i) in response to different levels of incident photon flux densities at similar photosynthetic capacities among Euonymus leaves and (ii) as a result of very different photosynthetic capacities among species at similar incident photon flux densities (that were equivalent to full sunlight). For Euonymus as well as the interspecific comparison all data fell on one single, close relationship for changes in intrinsic PSII efficiency, nonphotochemical fluorescence quenching, or the levels of zeaxanthin + antheraxanthin in leaves, respectively, as a function of the actual level of light stress. Thus, the same conversion state of the xanthophyll cycle and the same level of energy dissipation were observed for a given degree of light stress independent of species or conditions causing the light stress. Since all increases in thermal energy dissipation were associated with increases in the levels of zeaxanthin + antheraxanthin in these leaves, there was thus no indication of any form of xanthophyll cycle-independent energy dissipation in any of the twenty-four species or varieties of plants examined in their natural environment. It is also concluded that transient diurnal changes in intrinsic PSII efficiency in nature are caused by changes in the efficiency with which excitation energy is delivered from the antennae to PSII centers, and are thus likely to be purely photoprotective. Consequently, the possibility of quantifying the allocation of absorbed light into PSII photochemistry versus energy dissipation in the antennae from changes in intrinsic PSII efficiency is explored.

The main idea behind this book is to present a rigorous derivation of the equations that govern light propagation in highly scattering media, with an emphasis on their applications in imaging in biology and medicine. The equations and formulas for diffuse light propagation are derived from the very beginning, and all the necessary analytical expressions needed to complete a complex imaging or characterization problem are presented step by step.