Download or read book Electronic Structure of Germanium Nanocrystal Films Probed with Synchrotron Radiation written by Christoph Bostedt and published by . This book was released on 2002 with total page 135 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electronic Structure of Germanium Nanocrystal Films Probed with Synchrotron Radiation written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The fundamental structure--property relationship of semiconductor quantum dots has been investigated. For deposited germanium nanocrystals strong quantum confinement effects have been determined with synchrotron radiation based x-ray absorption and photoemission techniques. The nanocrystals are condensed out of the gas phase with a narrow size distribution and subsequently deposited in situ onto various substrates. The particles are crystalline in the cubic phase with a structurally disordered surface shell and the resulting film morphology depends strongly on the substrate material and condition. The disordered surface region has an impact on the overall electronic structure of the particles. In a size-dependent study, the conduction and valence band edge of germanium nanocrystals have been measured for the first time and compared to the bulk crystal. The band edges move to higher energies as the particle size is decreased, consistent with quantum confinement theory. To obtain a more accurate analysis of confinement effects in the empty states, a novel analysis method utilizing an effective particle size for the x-ray absorption experiment, which allows a deconvolution of absorption edge broadening effects, has been introduced. Comparison of the present study to earlier studies on silicon reveals that germanium exhibits stronger quantum confinement effects than silicon. Below a critical particle size of 2.3 " 0.7 nm, the band gap of germanium becomes larger than that of silicon--even if it is the opposite for bulk materials. This result agrees phenomenologically with effective mass and tight binding theories but contradicts the findings of recent pseudopotential calculations. The discrepancy between theory and experiments is attributed to the differences in the theoretical models and experimental systems. The experimentally observed structural disorder of the particle surface has to be included in the theoretical models.
Download or read book Electronic Structure and Orientation of Self assembled Films and Metal Complexes Investigated with Synchrotron Radiation written by Dorothee Brovelli and published by . This book was released on 1999 with total page 151 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nanosilicon written by Anatoly A. Ischenko and published by CRC Press. This book was released on 2014-07-23 with total page 757 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanosilicon: Properties, Synthesis, Applications, Methods of Analysis and Control examines the latest developments on the physics and chemistry of nanosilicon. The book focuses on methods for producing nanosilicon, its electronic and optical properties, research methods to characterize its spectral and structural properties, and its possible applications. The first part of the book covers the basic properties of semiconductors, including causes of the size dependence of the properties, structural and electronic properties, and physical characteristics of the various forms of silicon. It presents theoretical and experimental research results as well as examples of porous silicon and quantum dots. The second part discusses the synthesis of nanosilicon, modification of the surface of nanoparticles, and properties of the resulting particles. The authors give special attention to the photoluminescence of silicon nanoparticles. The third part describes methods used for studying and controlling the structure and properties of nanocrystalline silicon. These methods include standard ones, such as electron microscopy, spectroscopy, and diffraction, as well as novel techniques, such as femtosecond spectroscopy, ultrafast electron nanocrystallography, and dynamic transmission electron microscopy. The fourth part details some of the practical applications of nanocrystalline silicon, including the use of nanoparticles as additives–absorbers of UV radiation in sunscreens. Incorporating much of the authors’ own extensive research results, this book provides a systematic account of the scientific problems of nanosilicon and its potential practical applications. It will help readers understand current and emerging applications and research methods of this unique material.
Download or read book Proceedings of the 11th International Conference on Vacuum Ultraviolet Radiation Physics written by T. Miyahara and published by Elsevier. This book was released on 2012-12-02 with total page 590 pages. Available in PDF, EPUB and Kindle. Book excerpt: These volumes contain 365 of the 505 papers presented at the VUV-11 Conference, held at Rikkyo University, Tokyo, from August 27th to September 1st 1995. The papers are divided into three sections: atomic and molecular spectroscopy, solid state spectroscopy and instrumentation and technological applications. New aspects presented were both quantitative and qualitative improvements in fluorescence spectroscopy and magnetic circular dichroism measurements. The fluorescence data are complementary to those of photoemission in a sense but they appear to open up a new method to analyze the optical excitation and relaxation processes. The application of magnetic circular dichroism has proved to be useful not only in analyzing the electronic structures of magnetic materials but also in practical applications to material engineering as found in experiments combined with photoelectron microscopy. Excellent developments in applications are only found in the field of surface photochemistry, where the technique of etching using VUV light has been appreciably refined. Although the majority of distinctive scientific features in the VUV-11 Conference have been brought about by the application of synchrotron radiation, experiments using a different type of light source appear to have progressed steadily. This is evident in the studies of plasma radiation.
Download or read book Canadian Journal of Chemistry written by and published by . This book was released on 2007 with total page 736 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Chemical Abstracts written by and published by . This book was released on 2002 with total page 2540 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synchrotron Radiation written by Settimio Mobilio and published by Springer. This book was released on 2014-08-06 with total page 807 pages. Available in PDF, EPUB and Kindle. Book excerpt: Synchrotron radiation is today extensively used for fundamental and applied research in many different fields of science. Its exceptional characteristics in terms of intensity, brilliance, spectral range, time structure and now also coherence pushed many experimental techniques to previously un-reachable limits, enabling the performance of experiments unbelievable only few years ago. The book gives an up-to-date overview of synchrotron radiation research today with a view to the future, starting from its generation and sources, its interaction with matter, illustrating the main experimental technique employed and provides an overview of the main fields of research in which new and innovative results are obtained. The book is addressed to PhD students and young researchers to provide both an introductory and a rather deep knowledge of the field. It will also be helpful to experienced researcher who want to approach the field in a professional way.
Download or read book X Ray Absorption and X Ray Emission Spectroscopy written by Jeroen A. van Bokhoven and published by John Wiley & Sons. This book was released on 2016-03-21 with total page 940 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the last two decades, remarkable and often spectacular progress has been made in the methodological and instrumental aspects of x–ray absorption and emission spectroscopy. This progress includes considerable technological improvements in the design and production of detectors especially with the development and expansion of large-scale synchrotron reactors All this has resulted in improved analytical performance and new applications, as well as in the perspective of a dramatic enhancement in the potential of x–ray based analysis techniques for the near future. This comprehensive two-volume treatise features articles that explain the phenomena and describe examples of X–ray absorption and emission applications in several fields, including chemistry, biochemistry, catalysis, amorphous and liquid systems, synchrotron radiation, and surface phenomena. Contributors explain the underlying theory, how to set up X–ray absorption experiments, and how to analyze the details of the resulting spectra. X-Ray Absorption and X-ray Emission Spectroscopy: Theory and Applications: Combines the theory, instrumentation and applications of x-ray absorption and emission spectroscopies which offer unique diagnostics to study almost any object in the Universe. Is the go-to reference book in the subject for all researchers across multi-disciplines since intense beams from modern sources have revolutionized x-ray science in recent years Is relevant to students, postdocurates and researchers working on x-rays and related synchrotron sources and applications in materials, physics, medicine, environment/geology, and biomedical materials
Download or read book Nanoscale Photonic Imaging written by Tim Salditt and published by Springer Nature. This book was released on 2020-06-09 with total page 634 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book, edited and authored by a team of world-leading researchers, provides a broad overview of advanced photonic methods for nanoscale visualization, as well as describing a range of fascinating in-depth studies. Introductory chapters cover the most relevant physics and basic methods that young researchers need to master in order to work effectively in the field of nanoscale photonic imaging, from physical first principles, to instrumentation, to mathematical foundations of imaging and data analysis. Subsequent chapters demonstrate how these cutting edge methods are applied to a variety of systems, including complex fluids and biomolecular systems, for visualizing their structure and dynamics, in space and on timescales extending over many orders of magnitude down to the femtosecond range. Progress in nanoscale photonic imaging in Göttingen has been the sum total of more than a decade of work by a wide range of scientists and mathematicians across disciplines, working together in a vibrant collaboration of a kind rarely matched. This volume presents the highlights of their research achievements and serves as a record of the unique and remarkable constellation of contributors, as well as looking ahead at the future prospects in this field. It will serve not only as a useful reference for experienced researchers but also as a valuable point of entry for newcomers.
Download or read book Modern Techniques of Surface Science written by D. P. Woodruff and published by Cambridge University Press. This book was released on 1994-03-03 with total page 612 pages. Available in PDF, EPUB and Kindle. Book excerpt: Revised and expanded second edition of the standard work on new techniques for studying solid surfaces.
Download or read book Gas Phase Synthesis of Nanoparticles written by Yves Huttel and published by John Wiley & Sons. This book was released on 2017-06-19 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first overview of this topic begins with some historical aspects and a survey of the principles of the gas aggregation method. The second part covers modifications of this method resulting in different specialized techniques, while the third discusses the post-growth treatment that can be applied to the nanoparticles. The whole is rounded off by a review of future perspectives and the challenges facing the scientific and industrial communities. An excellent resource for anyone working with the synthesis of nanoparticles, both in academia and industry.
Download or read book Advanced Nanomaterials and Their Applications in Renewable Energy written by Jingbo Louise Liu and published by Elsevier. This book was released on 2015-08-06 with total page 461 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advanced Nanomaterials and Their Applications in Renewable Energy presents timely topics related to nanomaterials' feasible synthesis and characterization, and their application in the energy fields. In addition, the book provides insights and scientific discoveries in toxicity study, with information that is easily understood by a wide audience. Advanced energy materials are important in designing materials that have greater physical, electronic, and optical properties. This book emphasizes the fundamental physics and chemistry underlying the techniques used to develop solar and fuel cells with high charge densities and energy conversion efficiencies. New analytical techniques (synchronous X-ray) which probe the interactions of particles and radiation with matter are also explored, making this book an invaluable reference for practitioners and those interested in the science. Provides a comprehensive review of solar energy, fuel cells, and gas storage from 2010 to the present Reviews feasible synthesis and modern analytical techniques used in alternative energy Explores examples of research in alternative energy, including current assessments of nanomaterials and safety Contains a glossary of terms, units, and historical benchmarks Presents a useful guide that will bring readers up to speed on historical developments in alternative fuel cells
Download or read book Metals Abstracts written by and published by . This book was released on 1998 with total page 1076 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book International Aerospace Abstracts written by and published by . This book was released on 1998 with total page 980 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Visualizing Chemistry written by National Research Council and published by National Academies Press. This book was released on 2006-06-01 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt: Scientists and engineers have long relied on the power of imaging techniques to help see objects invisible to the naked eye, and thus, to advance scientific knowledge. These experts are constantly pushing the limits of technology in pursuit of chemical imagingâ€"the ability to visualize molecular structures and chemical composition in time and space as actual events unfoldâ€"from the smallest dimension of a biological system to the widest expanse of a distant galaxy. Chemical imaging has a variety of applications for almost every facet of our daily lives, ranging from medical diagnosis and treatment to the study and design of material properties in new products. In addition to highlighting advances in chemical imaging that could have the greatest impact on critical problems in science and technology, Visualizing Chemistry reviews the current state of chemical imaging technology, identifies promising future developments and their applications, and suggests a research and educational agenda to enable breakthrough improvements.
Download or read book X ray and Neutron Techniques for Nanomaterials Characterization written by Challa S.S.R. Kumar and published by Springer. This book was released on 2016-10-13 with total page 835 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fifth 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 X-ray and Neutron Techniques for Nanomaterials Characterization. Modern applications and state-of-the-art techniques are covered and make this volume an essential reading for research scientists in academia and industry.
