Author : George A. Haas
Publisher :
Page : 38 pages
File Size : 28,35 MB
Release : 1961
Category : Thermionic emission
ISBN :
A survey of the emission characteristics of modern thermionic electron sources is presented. In addition to a discussion of recent advances among the more commonly used emitters such as oxide cathodes, thoriated cathodes, and metal c thodes, a tabulation of the thermionic properties of over one hundred various new matrix and refractory-coated cathodes is given. (Author).
Author : David B. Williams
Publisher : Springer Science & Business Media
Page : 708 pages
File Size : 43,45 MB
Release : 2013-03-09
Category : Science
ISBN : 1475725191
Electron microscopy has revolutionized our understanding the extraordinary intellectual demands required of the mi of materials by completing the processing-structure-prop croscopist in order to do the job properly: crystallography, erties links down to atomistic levels. It now is even possible diffraction, image contrast, inelastic scattering events, and to tailor the microstructure (and meso structure ) of materials spectroscopy. Remember, these used to be fields in them to achieve specific sets of properties; the extraordinary abili selves. Today, one has to understand the fundamentals ties of modem transmission electron microscopy-TEM of all of these areas before one can hope to tackle signifi instruments to provide almost all of the structural, phase, cant problems in materials science. TEM is a technique of and crystallographic data allow us to accomplish this feat. characterizing materials down to the atomic limits. It must Therefore, it is obvious that any curriculum in modem mate be used with care and attention, in many cases involving rials education must include suitable courses in electron mi teams of experts from different venues. The fundamentals croscopy. It is also essential that suitable texts be available are, of course, based in physics, so aspiring materials sci for the preparation of the students and researchers who must entists would be well advised to have prior exposure to, for carry out electron microscopy properly and quantitatively.
Author : Georg Gaertner
Publisher : Springer Nature
Page : 609 pages
File Size : 29,98 MB
Release : 2020-10-09
Category : Technology & Engineering
ISBN : 3030472914
This book gives an overview of modern cathodes and electron emitters for vacuum tubes and vacuum electron devices in general. It covers the latest developments in field emission theory as well as new methods towards improving thermionic and cold cathodes. It addresses thermionic cathodes, such as oxide cathodes, impregnated and scandate cathodes, as well as photocathodes and field emitters – the latter comprising carbon nanotubes, graphene and Spindt-type emitter arrays. Despite the rise and fall of the once dominant types of vacuum tubes, such as radio valves and cathode ray tubes, cathodes are continually being improved upon as new applications with increased demands arise, for example in electron beam lithography, high-power and high-frequency microwave tubes, terahertz imaging and electron sources for accelerators. Written by 17 experts in the field, the book presents the latest developments in cathodes needed for these applications, discussing the state of the art and addressing future trends.
Author : Yahachi Saito
Publisher : CRC Press
Page : 374 pages
File Size : 13,51 MB
Release : 2022-01-27
Category : Science
ISBN : 1000333795
Carbon forms a variety of allotropes due to the diverse hybridization of s- and p-electron orbitals, including the time-honored graphite and diamond as well as new forms such as C60 fullerene, nanotubes, graphene, and carbyne. The new family of carbon isotopes—fullerene, nanotubes, graphene, and carbyne—is called “nanostructured carbon” or “nanocarbon.” These isotopes exhibit extreme properties such as ultrahigh mechanical strength, ultrahigh charge–carrier mobility, and high thermal conductivity, attracting considerable attention for their electronic and mechanical applications as well as for exploring new physics and chemistry in the field of basic materials science. Electron sources are important in a wide range of areas, from basic physics and scientific instruments to medical and industrial applications. Carbon nanotubes (CNTs) and graphene behave as excellent electron-field emitters owing to their exceptional properties and offer several benefits compared to traditional cathodes. Field emission (FE) produces very intense electron currents from a small surface area with a narrow energy spread, providing a highly coherent electron beam—a combination that not only provides us with the brightest electron sources but also explores a new field of electron beam–related research. This book presents the enthusiastic research and development of CNT-based FE devices and focuses on the fundamental aspects of FE from nanocarbon materials, including CNTs and graphene, and the latest research findings related to it. It discusses applications of FE to X-ray and UV generation and reviews electron sources in vacuum electronic devices and space thrusters. Finally, it reports on the new forms of carbon produced via FE from CNT.
Author : Richard G. Carter
Publisher : Cambridge University Press
Page : 843 pages
File Size : 14,89 MB
Release : 2018-04-12
Category : Technology & Engineering
ISBN : 0521198623
Get up-to-speed on the theory, principles and design of vacuum electron devices.
Author : Jon Orloff
Publisher : CRC Press
Page : 938 pages
File Size : 49,20 MB
Release : 2017-12-19
Category : Science
ISBN : 1351835777
With the growing proliferation of nanotechnologies, powerful imaging technologies are being developed to operate at the sub-nanometer scale. The newest edition of a bestseller, the Handbook of Charged Particle Optics, Second Edition provides essential background information for the design and operation of high resolution focused probe instruments. The book’s unique approach covers both the theoretical and practical knowledge of high resolution probe forming instruments. The second edition features new chapters on aberration correction and applications of gas phase field ionization sources. With the inclusion of additional references to past and present work in the field, this second edition offers perfectly calibrated coverage of the field’s cutting-edge technologies with added insight into how they work. Written by the leading research scientists, the second edition of the Handbook of Charged Particle Optics is a complete guide to understanding, designing, and using high resolution probe instrumentation.
Author : National Research Council
Publisher : National Academies Press
Page : 85 pages
File Size : 34,91 MB
Release : 2001-12-18
Category : Science
ISBN : 0309086868
This report evaluates the Defense Threat Reduction Agency prior and present sponsored efforts; assess the present state of the art in thermionic energy conversion systems; assess the technical challenges to the development of viable thermionic energy conversion systems for both space and terrestrial applications; and recommend a prioritized set of objectives for a future research and development program for advanced thermionic systems for space and terrestrial applications.
Author : Ludwig Reimer
Publisher : Springer
Page : 538 pages
File Size : 27,54 MB
Release : 2013-11-11
Category : Science
ISBN : 3540389679
Scanning Electron Microscopy provides a description of the physics of electron-probe formation and of electron-specimen interactions. The different imaging and analytical modes using secondary and backscattered electrons, electron-beam-induced currents, X-ray and Auger electrons, electron channelling effects, and cathodoluminescence are discussed to evaluate specific contrasts and to obtain quantitative information.
Author : David B. Williams
Publisher : Springer Science & Business Media
Page : 804 pages
File Size : 11,6 MB
Release : 2009-08-05
Category : Science
ISBN : 038776500X
This groundbreaking text has been established as the market leader throughout the world. Profusely illustrated, the book provides the necessary instructions for successful hands-on application of this versatile materials characterization technique.
Author : C. Barry Carter
Publisher : Springer
Page : 543 pages
File Size : 23,19 MB
Release : 2016-08-24
Category : Technology & Engineering
ISBN : 3319266519
This text is a companion volume to Transmission Electron Microscopy: A Textbook for Materials Science by Williams and Carter. The aim is to extend the discussion of certain topics that are either rapidly changing at this time or that would benefit from more detailed discussion than space allowed in the primary text. World-renowned researchers have contributed chapters in their area of expertise, and the editors have carefully prepared these chapters to provide a uniform tone and treatment for this exciting material. The book features an unparalleled collection of color figures showcasing the quality and variety of chemical data that can be obtained from today’s instruments, as well as key pitfalls to avoid. As with the previous TEM text, each chapter contains two sets of questions, one for self assessment and a second more suitable for homework assignments. Throughout the book, the style follows that of Williams & Carter even when the subject matter becomes challenging—the aim is always to make the topic understandable by first-year graduate students and others who are working in the field of Materials Science Topics covered include sources, in-situ experiments, electron diffraction, Digital Micrograph, waves and holography, focal-series reconstruction and direct methods, STEM and tomography, energy-filtered TEM (EFTEM) imaging, and spectrum imaging. The range and depth of material makes this companion volume essential reading for the budding microscopist and a key reference for practicing researchers using these and related techniques.
