Functional Dielectrics for Electronics

Functional Dielectrics for Electronics
Author: Yuriy M. Poplavko,Yuriy Yakimenko
Publsiher: Woodhead Publishing
Total Pages: 312
Release: 2020-01-29
ISBN 10: 0128188367
ISBN 13: 9780128188361
Language: EN, FR, DE, ES & NL

Functional Dielectrics for Electronics Book Review:

Functional Dielectrics for Electronics: Fundamentals of Conversion Properties presents an overview of the nature of electrical polarization, dielectric nonlinearity, electrical charge transfer mechanisms, thermal properties, the nature of high permittivity, low-loss thermostability and other functional dielectrics. The book describes the intrinsic mechanisms of electrical polarization and the energy transformations in non-centrosymmetric crystals that are responsible for converting thermal, mechanical, optical and other impacts into electrical signals. In addition, the book reviews the main physical processes that provide electrical, mechanoelectrical, thermoelectrical and other conversion phenomena in polar crystals. Detailed descriptions are given to electrical manifestations of polar-sensitivity in the crystals, the interaction of polarization with conductivity, the anomalies in thermal expansion coefficient and main peculiarities of heat transfer in polar-sensitive crystals. Provides readers with a fundamental understanding of polar dielectric materials and their physical processes Includes different models of polar sensitivity and experimental confirmation of these models Discusses thermal expansion, heat transfer, dielectric nonlinearity and other important aspects for electronics applications

Functional Dielectrics for Electronics

Functional Dielectrics for Electronics
Author: Yuriy M. Poplavko,Yuriy Yakymenko
Publsiher: Woodhead Publishing Limited
Total Pages: 312
Release: 2020-01-17
ISBN 10: 0128188359
ISBN 13: 9780128188354
Language: EN, FR, DE, ES & NL

Functional Dielectrics for Electronics Book Review:

Functional Dielectrics for Electronics: Fundamentals of Conversion Properties presents an overview of the nature of electrical polarization, dielectric nonlinearity, electrical charge transfer mechanisms, thermal properties, the nature of high permittivity, low-loss thermostability and other functional dielectrics. The book describes the intrinsic mechanisms of electrical polarization and the energy transformations in non-centrosymmetric crystals that are responsible for converting thermal, mechanical, optical and other impacts into electrical signals. In addition, the book reviews the main physical processes that provide electrical, mechanoelectrical, thermoelectrical and other conversion phenomena in polar crystals. Detailed descriptions are given to electrical manifestations of polar-sensitivity in the crystals, the interaction of polarization with conductivity, the anomalies in thermal expansion coefficient and main peculiarities of heat transfer in polar-sensitive crystals. Provides readers with a fundamental understanding of polar dielectric materials and their physical processes Includes different models of polar sensitivity and experimental confirmation of these models Discusses thermal expansion, heat transfer, dielectric nonlinearity and other important aspects for electronics applications

Dielectric Spectroscopy of Electronic Materials

Dielectric Spectroscopy of Electronic Materials
Author: Yuriy Poplavko
Publsiher: Woodhead Publishing
Total Pages: 376
Release: 2021-07-06
ISBN 10: 0128236442
ISBN 13: 9780128236444
Language: EN, FR, DE, ES & NL

Dielectric Spectroscopy of Electronic Materials Book Review:

Dielectric Spectroscopy of Electronic Materials: Applied Physics of Dielectrics incorporates the results of four decades of research and applications of dielectric spectroscopy for solids, mostly for the investigation of materials used in electronics. The book differs from others by more detailed analysis of the features of dielectric spectra conditioned by specific mechanisms of electrical polarization and conductivity. Some original methods are presented in the simulation of frequency distributions (relaxers and oscillators), with methods proposed for various ferroelectrics frequency-temperature dielectric spectra. Also described are original methods for ferroelectrics on microwaves investigation, including the features of thin films study. The book is not burdened by complex mathematical proofs and should help readers quickly understand how to apply dielectric spectroscopy methods to their own research problems. More advanced readers may also find this book valuable as a review of the key concepts and latest advances on the topics presented. Introduces critical material characterization techniques by an expert with more than 40 years of experience in dielectric spectroscopy Reviews advances in dielectric spectroscopy methods to enable advances such as the miniaturization of electronics at the nanoscale Provides an overview of polarization mechanisms utilizing different models (i.e., oscillator and relaxation)

Functional Materials

Functional Materials
Author: Deborah D L Chung
Publsiher: World Scientific Publishing Company
Total Pages: 364
Release: 2010-03-30
ISBN 10: 9813101016
ISBN 13: 9789813101012
Language: EN, FR, DE, ES & NL

Functional Materials Book Review:

The development of functional materials is at the heart of technological needs and the forefront of materials research. This book provides a comprehensive and up-to-date treatment of functional materials, which are needed for electrical, dielectric, electromagnetic, optical, and magnetic applications. Materials concepts covered are strongly linked to applications. Textbooks related to functional materials have not kept pace with technological needs and associated scientific advances. Introductory materials science textbooks merely gloss over functional materials while electronic materials textbooks focus on semiconductors and smart materials textbooks emphasize more on limited properties that pertain to structures. Functional Materials assumes that the readers have had a one-semester introductory undergraduate course on materials science. The coverage on functional materials is much broader and deeper than that of an introductory materials science course. The book features hundreds of illustrations to help explain concepts and provide quantitative information. The style is general towards tutorial. Most chapters include sections on example problems, review questions and supplementary reading. This book is suitable for use as a textbook in undergraduate and graduate engineering courses. It is also suitable for use as a reference book for professionals in the electronic, computer, communication, aerospace, automotive, transportation, construction, energy and control industries. Request Inspection Copy

Functional Materials Electrical Dielectric Electromagnetic Optical And Magnetic Applications Second Edition

Functional Materials  Electrical  Dielectric  Electromagnetic  Optical And Magnetic Applications  Second Edition
Author: Deborah D L Chung
Publsiher: World Scientific
Total Pages: 552
Release: 2021-10-28
ISBN 10: 9811238855
ISBN 13: 9789811238857
Language: EN, FR, DE, ES & NL

Functional Materials Electrical Dielectric Electromagnetic Optical And Magnetic Applications Second Edition Book Review:

The field of functional materials has grown tremendously over the last 5-10 years, due to its richness in both science and applications. This timely compendium covers the science and applications of functional materials in a comprehensive manner that is suitable for readers that do not have background on the electrical, dielectric, electromagnetic, optical and magnetic properties of materials. Prior knowledge of quantum mechanics or solid state physics is also not required. Only a semester of introductory materials science suffices.This unique reference text is tutorial in style and includes numerous example problems, which are lacking in several competing books in the market.The must-have volume benefits undergraduate and graduate students in materials science, mechanical engineering, electrical engineering and aerospace engineering.

Electronic Materials

Electronic Materials
Author: Yuriy M. Poplavko
Publsiher: Elsevier
Total Pages: 707
Release: 2018-11-23
ISBN 10: 0128152567
ISBN 13: 9780128152560
Language: EN, FR, DE, ES & NL

Electronic Materials Book Review:

Mechanical and thermal properties are reviewed and electrical and magnetic properties are emphasized. Basics of symmetry and internal structure of crystals and the main properties of metals, dielectrics, semiconductors, and magnetic materials are discussed. The theory and modern experimental data are presented, as well as the specifications of materials that are necessary for practical application in electronics. The modern state of research in nanophysics of metals, magnetic materials, dielectrics and semiconductors is taken into account, with particular attention to the influence of structure on the physical properties of nano-materials. The book uses simplified mathematical treatment of theories, while emphasis is placed on the basic concepts of physical phenomena in electronic materials. Most chapters are devoted to the advanced scientific and technological problems of electronic materials; in addition, some new insights into theoretical facts relevant to technical devices are presented. Electronic Materials is an essential reference for newcomers to the field of electronics, providing a fundamental understanding of important basic and advanced concepts in electronic materials science. Provides important overview of the fundamentals of electronic materials properties significant for device applications along with advanced and applied concepts essential to those working in the field of electronics Takes a simplified and mathematical approach to theories essential to the understanding of electronic materials and summarizes important takeaways at the end of each chapter Interweaves modern experimental data and research in topics such as nanophysics, nanomaterials and dielectrics

Nanostructured Semiconductor Oxides for the Next Generation of Electronics and Functional Devices

Nanostructured Semiconductor Oxides for the Next Generation of Electronics and Functional Devices
Author: Serge Zhuiykov
Publsiher: Woodhead Publishing
Total Pages: 466
Release: 2014-02-14
ISBN 10: 1782422242
ISBN 13: 9781782422242
Language: EN, FR, DE, ES & NL

Nanostructured Semiconductor Oxides for the Next Generation of Electronics and Functional Devices Book Review:

Nanostructured Semiconductor Oxides for the Next Generation of Electronics and Functional Devices focuses on the development of semiconductor nanocrystals, their technologies and applications, including energy harvesting, solar cells, solid oxide fuel cells, and chemical sensors. Semiconductor oxides are used in electronics, optics, catalysts, sensors, and other functional devices. In their 2D form, the reduction in size confers exceptional properties, useful for creating faster electronics and more efficient catalysts. After explaining the physics affecting the conductivity and electron arrangement of nanostructured semiconductors, the book addresses the structural and chemical modification of semiconductor nanocrystals during material growth. It then covers their use in nanoscale functional devices, particularly in electronic devices and carbon nanotubes. It explores the impact of 2D nanocrystals, such as graphene, chalcogenides, and oxide nanostructures, on research and technology, leading to a discussion of incorporating graphene and semiconductor nanostructures into composites for use in energy storage. The final three chapters focus on the applications of these functional materials in photovoltaic cells, solid oxide fuel cells, and in environmental sensors including pH, dissolved oxygen, dissolved organic carbon, and dissolved metal ion sensors. Nanostructured Semiconductor Oxides for the Next Generation of Electronics and Functional Devices is a crucial resource for scientists, applied researchers, and production engineers working in the fabrication, design, testing, characterization, and analysis of new semiconductor materials. This book is a valuable reference for those working in the analysis and characterization of new nanomaterials, and for those who develop technologies for practical devices fabrication. Focuses on the development of semiconductor nanocrystals, their technologies and applications, including energy harvesting, solar cells, solid oxide fuel cells, and chemical sensors Reviews fundamental physics of conductivity and electron arrangement before proceeding to practical applications A vital resource for applied researchers and production engineers working with new semiconductor materials

Integrated Circuits Microchips

Integrated Circuits Microchips
Author: Kim Ho Yeap,Jonathan Sayago
Publsiher: BoD – Books on Demand
Total Pages: 204
Release: 2020-09
ISBN 10: 1789859301
ISBN 13: 9781789859300
Language: EN, FR, DE, ES & NL

Integrated Circuits Microchips Book Review:

Functional Nanomaterials and Devices for Electronics Sensors and Energy Harvesting

Functional Nanomaterials and Devices for Electronics  Sensors and Energy Harvesting
Author: Alexei Nazarov,Francis Balestra,Valeriya Kilchytska,Denis Flandre
Publsiher: Springer
Total Pages: 469
Release: 2014-08-28
ISBN 10: 3319088041
ISBN 13: 9783319088044
Language: EN, FR, DE, ES & NL

Functional Nanomaterials and Devices for Electronics Sensors and Energy Harvesting Book Review:

This book contains reviews of recent experimental and theoretical results related to nanomaterials. It focuses on novel functional materials and nanostructures in combination with silicon on insulator (SOI) devices, as well as on the physics of new devices and sensors, nanostructured materials and nano scaled device characterization. Special attention is paid to fabrication and properties of modern low-power, high-performance, miniaturized, portable sensors in a wide range of applications such as telecommunications, radiation control, biomedical instrumentation and chemical analysis. In this book, new approaches exploiting nanotechnologies (such as UTBB FD SOI, Fin FETs, nanowires, graphene or carbon nanotubes on dielectric) to pave a way between “More Moore” and “More than Moore” are considered, in order to create different kinds of sensors and devices which will consume less electrical power, be more portable and totally compatible with modern microelectronics products.

Biopolymer Composites in Electronics

Biopolymer Composites in Electronics
Author: Kishor Kumar Sadasivuni,John-John Cabibihan,Deepalekshmi Ponnamma,Mariam Ali S A Al-Maadeed,Jaehwan Kim
Publsiher: Elsevier
Total Pages: 544
Release: 2016-09-10
ISBN 10: 0081009747
ISBN 13: 9780081009741
Language: EN, FR, DE, ES & NL

Biopolymer Composites in Electronics Book Review:

Biopolymer Composites in Electronics examines the current state-of-the-art in the electronic application based on biopolymer composites. Covering the synthesis, dispersion of fillers, characterization and fabrication of the composite materials, the book will help materials scientists and engineers address the challenges posed by the increased use of biopolymeric materials in electronic applications. The influence of preparation techniques on the generation of micro, meso, and nanoscale fillers, and the effect of filler size and dispersion on various biopolymers are discussed in detail. Applications covered include sensors, actuators, optics, fuel cells, photovoltaics, dielectrics, electromagnetic shielding, piezoelectrics, flexible displays, and microwave absorbers. In addition, characterization techniques are discussed and compared, enabling scientists and engineers to make the correct choice of technique. This book is a ‘one-stop’ reference for researchers, covering the entire state-of-the-art in biopolymer electronics. Written by a collection of expert worldwide contributors from industry, academia, government, and private research institutions, it is an outstanding reference for researchers in the field of biopolymer composites for advanced technologies. Enables researchers to keep up with the rapid development of biopolymer electronics, which offer light, flexible, and more cost-effective alternatives to conventional materials of solar cells, light-emitting diodes, and transistors Includes thorough coverage of the physics and chemistry behind biopolymer composites, helping readers to become rapidly acquainted with the fiel Provides in-depth information on the range of biopolymer applications in electronics, from printed flexible conductors and novel semiconductor components, to intelligent labels, large area displays, and solar panels

Nanooptics and Photonics Nanochemistry and Nanobiotechnology and Their Applications

Nanooptics and Photonics  Nanochemistry and Nanobiotechnology  and Their Applications
Author: Olena Fesenko,Leonid Yatsenko
Publsiher: Springer Nature
Total Pages: 322
Release: 2021-10-03
ISBN 10: 3030748006
ISBN 13: 9783030748005
Language: EN, FR, DE, ES & NL

Nanooptics and Photonics Nanochemistry and Nanobiotechnology and Their Applications Book Review:

This book highlights some of the latest advances in nanotechnology and nanomaterials from leading researchers in Ukraine, Europe and beyond. It features contributions presented at the 8th International Science and Practice Conference Nanotechnology and Nanomaterials (NANO2020), which was held on August 26–29, 2020 at Lviv Polytechnic National University, and was jointly organized by the Institute of Physics of the National Academy of Sciences of Ukraine, University of Tartu (Estonia), University of Turin (Italy), and Pierre and Marie Curie University (France). Internationally recognized experts from a wide range of universities and research institutions share their knowledge and key findings on material properties, behavior, and synthesis. This book’s companion volume also addresses topics such as nano-optics, energy storage, and biomedical applications.

Graphene Materials

Graphene Materials
Author: George Kyzas,Athanasios Mitropoulos
Publsiher: BoD – Books on Demand
Total Pages: 240
Release: 2017-05-17
ISBN 10: 9535131419
ISBN 13: 9789535131410
Language: EN, FR, DE, ES & NL

Graphene Materials Book Review:

Graphene is, basically, a single atomic layer of graphite, an abundant mineral that is an allotrope of carbon that is made up of very tightly bonded carbon atoms organized into a hexagonal lattice. What makes graphene so special is its sp2 hybridization and very thin atomic thickness (of 0.345 Nm). These properties are what enable graphene to break so many records in terms of strength, electricity, and heat conduction (as well as many others). This book gathers valuable information about many advanced applications of graphene (electrical, optical, environmental, cells, capacitors, etc).

Dielectric Materials and Applications

Dielectric Materials and Applications
Author: Mohammed Essaid Achour
Publsiher: Materials Research Forum LLC
Total Pages: 330
Release: 2016-12-15
ISBN 10: 1945291192
ISBN 13: 9781945291197
Language: EN, FR, DE, ES & NL

Dielectric Materials and Applications Book Review:

The First International Symposium on Dielectric Materials and Applications (ISyDMA’2016) was held in Kenitra (4 May, 2016) and in Rabat (May 5-6, 2016), Morocco. ISyDMA’2016 provided an international forum for reporting the most recent developments in Advanced Dielectric Materials and applications. The goal of this collection of peer reviewed papers is to provide researchers and scientists from all over the world with recent developments in dielectric materials and their innovative applications. The book will be useful for materials scientists, physicists, chemists, biologists, and electrical engineers engaged in fundamental and applied research or technical investigations of such materials.

Electrochemical Surface Modification

Electrochemical Surface Modification
Author: Richard C. Alkire,Dieter M. Kolb,Jacek Lipkowski,Phil N. Ross
Publsiher: John Wiley & Sons
Total Pages: 360
Release: 2008-11-21
ISBN 10: 3527625313
ISBN 13: 9783527625314
Language: EN, FR, DE, ES & NL

Electrochemical Surface Modification Book Review:

In this topical volume, the authors provide in-depth coverage of the vital relationship between electrochemistry and the morphology of thin films and surfaces. Clearly divided into four major sections, the book covers nanoscale dielectric films for electronic devices, superconformal film growth, electrocatalytic properties of transition metal macrocycles, and the use of synchrotron techniques in electrochemistry. All the chapters offer a concise introduction to the relevant topic, as well as supplying numerous references for easy access to further reading and the original literature. The result is must-have reading for electrochemists, physical and surface chemists and physicists, as well as materials scientists and engineers active in the field of spectroscopic methods in electrochemistry.

Advances in Nanotechnology Research and Application 2012 Edition

Advances in Nanotechnology Research and Application  2012 Edition
Author: Anonim
Publsiher: ScholarlyEditions
Total Pages: 14170
Release: 2012-12-26
ISBN 10: 1464990468
ISBN 13: 9781464990465
Language: EN, FR, DE, ES & NL

Advances in Nanotechnology Research and Application 2012 Edition Book Review:

Advances in Nanotechnology Research and Application / 2012 Edition is a ScholarlyEditions™ eBook that delivers timely, authoritative, and comprehensive information about Nanotechnology. The editors have built Advances in Nanotechnology Research and Application / 2012 Edition on the vast information databases of ScholarlyNews.™ You can expect the information about Nanotechnology in this eBook to be deeper than what you can access anywhere else, as well as consistently reliable, authoritative, informed, and relevant. The content of Advances in Nanotechnology Research and Application / 2012 Edition has been produced by the world’s leading scientists, engineers, analysts, research institutions, and companies. All of the content is from peer-reviewed sources, and all of it is written, assembled, and edited by the editors at ScholarlyEditions™ and available exclusively from us. You now have a source you can cite with authority, confidence, and credibility. More information is available at http://www.ScholarlyEditions.com/.

Ferroelectrics Research in the People s Republic of China

Ferroelectrics Research in the People s Republic of China
Author: Yin Zhiwen,Y. Zhiwen,Y. Xi,S. B. Lang
Publsiher: Taylor & Francis
Total Pages: 311
Release: 1990
ISBN 10: 9782881244292
ISBN 13: 2881244297
Language: EN, FR, DE, ES & NL

Ferroelectrics Research in the People s Republic of China Book Review:

Polymers in Organic Electronics

Polymers in Organic Electronics
Author: Sulaiman Khalifeh
Publsiher: Elsevier
Total Pages: 616
Release: 2020-04-01
ISBN 10: 192788568X
ISBN 13: 9781927885680
Language: EN, FR, DE, ES & NL

Polymers in Organic Electronics Book Review:

Polymers in Organic Electronics: Polymer Selection for Electronic, Mechatronic, and Optoelectronic Systems provides readers with vital data, guidelines, and techniques for optimally designing organic electronic systems using novel polymers. The book classifies polymer families, types, complexes, composites, nanocomposites, compounds, and small molecules while also providing an introduction to the fundamental principles of polymers and electronics. Features information on concepts and optimized types of electronics and a classification system of electronic polymers, including piezoelectric and pyroelectric, optoelectronic, mechatronic, organic electronic complexes, and more. The book is designed to help readers select the optimized material for structuring their organic electronic system. Chapters discuss the most common properties of electronic polymers, methods of optimization, and polymeric-structured printed circuit boards. The polymeric structures of optoelectronics and photonics are covered and the book concludes with a chapter emphasizing the importance of polymeric structures for packaging of electronic devices. Provides key identifying details on a range of polymers, micro-polymers, nano-polymers, resins, hydrocarbons, and oligomers Covers the most common electrical, electronic, and optical properties of electronic polymers Describes the underlying theories on the mechanics of polymer conductivity Discusses polymeric structured printed circuit boards, including their rapid prototyping and optimizing their polymeric structures Shows optimization methods for both polymeric structures of organic active electronic components and organic passive electronic components

Advanced Technical Ceramics Directory and Databook

Advanced Technical Ceramics Directory and Databook
Author: Robert John Hussey,Josephine Wilson
Publsiher: Springer Science & Business Media
Total Pages: 506
Release: 2012-09-08
ISBN 10: 1441986626
ISBN 13: 9781441986627
Language: EN, FR, DE, ES & NL

Advanced Technical Ceramics Directory and Databook Book Review:

Advanced Technical Ceramics Directory and Databook is a world-wide directory of the properties and suppliers of advanced technical ceramic material used in, or proposed for, numerous engineering applications. The information is subdivided into sections based on the class of ceramic, e.g. Nitrides-silicon nitride, sialon, boron carbide, aluminium nitride etc. Each section consists of a short introduction, a table comparing basic data and a series of data sheets. The book adopts standardised data in order to help the reader in finding and comparing different data and identifying the required information. It is designed to complement the existing Chapman & Hall publications on high performance materials.

European Miniature Electronic Components and Assemblies Data 1965 66 Including Six Language Glossaries of Electronic Component and Microelectronics Terms

European Miniature Electronic Components and Assemblies Data 1965 66  Including Six Language Glossaries of Electronic Component and Microelectronics Terms
Author: G. W. A. Dummer,J. Mackenzie Robertson
Publsiher: Elsevier
Total Pages: 1136
Release: 2016-07-21
ISBN 10: 1483150631
ISBN 13: 9781483150635
Language: EN, FR, DE, ES & NL

European Miniature Electronic Components and Assemblies Data 1965 66 Including Six Language Glossaries of Electronic Component and Microelectronics Terms Book Review:

European Miniature Electronic Components and Assemblies Data 1965-66: Including Six-Language Glossaries of Electronic Component and Microelectronics Terms, Part II, contains relevant glossaries, tables, and charts on the products of France, the Netherlands, Scandinavia, and Switzerland. These include a pictorial glossary of European electronic components; a glossary of terms in current use in microelectronics; useful abstracts of world publications on electronic components; multiple and submultiple prefixes; conversion table for standard prefixes; defined values and physical constants; and a temperature conversion table. Also provided are a table on fixed resistor color codes; a chart on the power loading of fixed resistors; tables on resistance for wires of various resistance alloys, wire gauges, and resistivities of resistance materials; fixed-capacitor selection charts; data on time-delay relays; and a torque conversion chart.

Dielectrics in Electric Fields

Dielectrics in Electric Fields
Author: Gorur Govinda Raju
Publsiher: CRC Press
Total Pages: 776
Release: 2017-07-28
ISBN 10: 1315350424
ISBN 13: 9781315350424
Language: EN, FR, DE, ES & NL

Dielectrics in Electric Fields Book Review:

Dielectrics in Electric Fields explores the influence of electric fields on dielectric—i.e., non-conducting or insulating—materials, examining the distinctive behaviors of these materials through well-established principles of physics and engineering. Featuring five new chapters, nearly 200 new figures, and more than 800 new citations, this fully updated and significantly expanded Second Edition: Analyzes inorganic substances with real-life applications in harsh working conditions such as outdoor, nuclear, and space environments Introduces methods for measuring dielectric properties at microwave frequencies, presenting results obtained for specific materials Discusses the application of dielectric theory in allied fields such as corrosion studies, civil engineering, and health sciences Combines in one chapter coverage of electrical breakdown in gases with breakdown in micrometric gaps Offers extensive coverage of electron energy distribution—essential knowledge required for the application of plasma sciences in medical science Delivers a detailed review of breakdown in liquids, along with an overview of electron mobility, providing a clear understanding of breakdown phenomena Explains breakdown in solid dielectrics such as single crystals, polycrystalline and amorphous states, thin films, and powders compressed to form pellets Addresses the latest advances in dielectric theory and research, including cutting-edge nanodielectric materials and their practical applications Blends early classical papers that laid the foundation for much of the dielectric theory with more recent work The author has drawn from more than 55 years of research studies and experience in the areas of high-voltage engineering, power systems, and dielectric materials and systems to supply both aspiring and practicing engineers with a comprehensive, authoritative source for up-to-date information on dielectrics in electric fields.