NATO Science Series II: Mathematics, Physics and Chemistry – serie

One of the most important issues in the construction of future magnetic confinement fusion machines is that of the materials of which they are constructed, and one of the key points of proper material choice is the recycle of hydrogen isotopes with materials at the plasma face. Tritium machines demand high safety and economy, which in turn requires the lowest possible T inventory and smallest possible permeation through the plasma facing materials. The recycle behaviour of the in-vessel components must also be known if the plasma reaction is to be predictable and controllable, and finally, the fuel cycle and plasma operating regimes may be actively controlled by special materials and methods. This book discusses both laboratory experiments exploring the basic properties of non-equilibrium hydrogen-solid systems (diffusion, absorption, boundary processes) and experimental results obtained from existing fusion machines under conditions simulating future situations to some extent. Contributions are from experts in the fields of nuclear fusion, materials science, surface science, vacuum science and technology, and solid state physics.

One of the most important issues in the construction of future magnetic confinement fusion machines is that of the materials of which they are constructed, and one of the key points of proper material choice is the recycle of hydrogen isotopes with materials at the plasma face. Tritium machines demand high safety and economy, which in turn requires the lowest possible T inventory and smallest possible permeation through the plasma facing materials. The recycle behaviour of the in-vessel components must also be known if the plasma reaction is to predictable and controllable, and finally, the fuel cycle and plasma operating regimes may be actively controlled by special materials and methods. The book discusses both laboratory experiments exploring the basic properties of non-equilibrium hydrogen-solid systems (diffusion, absorption, boundary processes) and experimental results obtained from existing fusion machines under conditions simulating future situations to some extent. Contributions are from experts in the fields of nuclear fusion, materials science, surface science, vacuum science and technology, and solid state physics.

Silicon dioxide plays a central role in most contemporary electronic and photonic technologies, from fiber optics for communications and medical applications to metal-oxide-semiconductor devices. Many of these applications directly involve point defects, which can either be introduced during the manufacturing process or by exposure to ionizing radiation. They can also be deliberately created to exploit new technologies. This book provides a general description of the influence that point defects have on the global properties of the bulk material and their spectroscopic characterization through ESR and optical spectroscopy.

Silicon dioxide plays a central role in most contemporary electronic and photonic technologies, from fiber optics for communications and medical applications to metal-oxide-semiconductor devices. Many of these applications directly involve point defects, which can either be introduced during the manufacturing process or by exposure to ionizing radiation. They can also be deliberately created to exploit new technologies. This book provides a general description of the influence that point defects have on the global properties of the bulk material and their spectroscopic characterization through ESR and optical spectroscopy.

This book contains papers presented at the NATO Advanced Research Workshop titled "Application of Gun and Rocket Propellants in Commercial Explosives". (SST.ARW975981) The workshop was organized in collaboration with codirector Dr. Bronislav V. Matseevich (KNIIM) and held in Krasnoarmeisk, Moscow Region, Russia, October 18-21, 1999. About 70 participants from 11 different countries took part in the meeting (Russia, Belarus, Czech Republic, Germany, Belgium, China, USA, Spain, Israel, Ukraine and the Netherlands). The workshop was principally the continuation of a previous NATO workshop on Conversion Concepts for Commercial Application and Disposal Technologies of Energetic Systems" held at Moscow, Russia, May 17-19, 1994 in the specific area of the reuse of gun and rocket propellants as ingredients in commercial explosives. Oldrich Machacek Vll ACKNOWLEDGMENTS I would like to thank Dr. B.V. Matseevich, Director of the Krasnoarmeisk Scientific Research Institute of Mechanization ("KNIIM") for his extensive involvement as co-director in organizing the Advanced Research Workshop in Krasnoarmeisk, Russia. Special thanks goes to Dr. V.P. Glinskij, Dr. LV. Vasiljeva and A.I. Fedonina from KNIIM and Dr. B. Vetlicky for invaluable assistance in preparation and the smooth operation ofthe workshop.

This book contains papers presented at the NATO Advanced Research Workshop titled "Application of Gun and Rocket Propellants in Commercial Explosives". (SST.ARW975981) The workshop was organized in collaboration with codirector Dr. Bronislav V. Matseevich (KNIIM) and held in Krasnoarmeisk, Moscow Region, Russia, October 18-21, 1999. About 70 participants from 11 different countries took part in the meeting (Russia, Belarus, Czech Republic, Germany, Belgium, China, USA, Spain, Israel, Ukraine and the Netherlands). The workshop was principally the continuation of a previous NATO workshop on Conversion Concepts for Commercial Application and Disposal Technologies of Energetic Systems" held at Moscow, Russia, May 17-19, 1994 in the specific area of the reuse of gun and rocket propellants as ingredients in commercial explosives. Oldrich Machacek Vll ACKNOWLEDGMENTS I would like to thank Dr. B.V. Matseevich, Director of the Krasnoarmeisk Scientific Research Institute of Mechanization ("KNIIM") for his extensive involvement as co-director in organizing the Advanced Research Workshop in Krasnoarmeisk, Russia. Special thanks goes to Dr. V.P. Glinskij, Dr. LV. Vasiljeva and A.I. Fedonina from KNIIM and Dr. B. Vetlicky for invaluable assistance in preparation and the smooth operation ofthe workshop.

A detailed presentation of the major role played by correctly designed and fabricated joints in the safe and reliable response of steel, composite and timber structures. The typology/morphology of connections is discussed for both conventional pinned and rigid joints and semi-rigid types. All relevant topics are comprehensively surveyed: definitions, classification, and influence of joint behaviour on overall structural response. Also presented are the application of the component method, the notion of rotational capacity, the local ductility of different types of earthquake-resistant structural joints as determined in cyclic experiments, numerical techniques for the realistic simulation of joint response, simple and moment-resistant structural connections. Readership: An incomparable resource for engineers who analyze and design steel, composite and timber structures; researchers and graduate students in the same areas.

An understanding of magnetostriction is important for a range of technologically and scientifically important materials. This book covers bulk and thin film magnetostrictive materials, superconductors and oxides. The role of magnetostriction in determining or influencing the physical properties is discussed in depth and wide-ranging reference lists are provided for further study. Contributors have provided both tutorial material and discussions.

An understanding of magnetostriction is important for a range of technologically and scientifically important materials. The book covers bulk and thin film magnetostrictive materials, superconductors and oxides. The role of magnetostriction in determining or influencing the physical properties is discussed in depth and wide-ranging reference lists are provided for further study. Contributors have provided both tutorial material and discussions of leading-edge science. Readership: An invaluable reference for all condensed matter physicists, material scientists and technologists for whom bulk or thin film magnetic materials or superconductors are central to their interests.

This text points out directions for future research in such different subjects as photonic band gap crystals, semiconductor quantum dot and wire lasers, silicon optoelectronics, carbon-based nanostructure physics, polymer based nano-composite and quantum wires, DNA nano-technology and silicon bio-compatibility, nano-scale optical characterisation, spray and cluster deposition, self assembly, imprint technology, quantum computing and quantum dot-based computation.

Since their discovery, low dimensional materials have never stopped to intrigue scientists, whether they are physicists, chemists, or biochemists. Investigations of their nature and functions have always been and still are numerous and as soon as a solution is found for a given question, another one is raised. The coupling of nano-materials with photonics, i. e. nano-photonics, has produced a boiling pot of idea, problems, discovery and applications. This statement is abundantly illustrated in the present book. The interest in nano-optoelectronic materials and systems is very widespread, what gives a really international and multicultural flavour to nano-optoelectronic meetings. One of them was organized by our-self in May 2000 in Kiev as a NATO Advanced Research Workshop and EC-Spring School. The arrival of the new millennium provides an obvious transition point at which many aspects of nano-science and nano-engineering of nano­ photonic systems can be assessed with respect to the research progresses made in the pre­ ceding decades and to the challenges that lie ahead in the coming decades. This book was planed to mark this with the objective of presenting a collection of papers from experts, which provide broad perspectives on the state-of-the-art in the various disciplines of nano­ science and nano-engineering and on the directions for future research.

Topology optimization of structures and composite materials is a new and rapidly expanding field of mechanics which is now coming to play a major role in most branches of engineering, such as aerospace, mechanical, structural, civil and materials. There are also significant implications for energy production and the building and material sciences. It a truly "high-tech" field, requiring advanced computer facilities and computational methods, while involving unusual theoretical considerations in pure mathematics. Topology optimization deals with some of the most intractable problems in the mechanical sciences, but is also of considerable practical interest in that it can achieve far greater savings than conventional (sizing or shape) optimization. Extensive research into topology optimization is being conducted in most developed countries. The present book describes the state of the art, bringing together researchers from a diversity of backgrounds: mathematicians, information scientists, aerospace, automotive, mechanical, structural and civil engineers.

Topology optimization of structures and composite materials is a new and rapidly expanding field of mechanics which now plays an ever-increasing role in most branches of technology, such as aerospace, mechanical, structural, civil and ma­ terials engineering, with important implications for energy production as well as building and environmental sciences. It is a truly "high-tech" field which requires advanced computer facilities and computational methods, whilst involving unusual theoretical considerations in pure mathematics. Topology optimization deals with some of the most difficult problems of mechanical sciences, but it is also of consid­ erable practical interest because it can achieve much greater savings than conven­ tional (sizing or shape) optimization. Extensive research into topology optimization is being carried out in most of the developed countries of the world. The workshop addressed the state of the art of the field, bringing together re­ searchers from a diversity of backgrounds (mathematicians, information scientists, aerospace, automotive, mechanical, structural and civil engineers) to span the full breadth and depth of the field and to outline future developments in research and avenues of cooperation between NATO and Partner countries. The program cov­ ered • theoretical (mathematical) developments, • computer algorithms, software development and computational difficulties, and • practical applications in various fields of technology. A novel feature of the workshop was that, in addition to shorter discussions after each lecture, a 30 minutes panel discussion took place in each sesssion, which made this ARW highly interactive and more informal.

What is a supermaterial? A concise definition is by no means obvious, but a clue can be obtained from the topics discussed here.. In addition to superconductors, the reader will encounter magnetic effects of many kinds, including giant and even colossal ones, organic conductors, photoconductors, and even 400-year-old Japanese ceramics. Processing is a prominent pursuit in supermaterials research, especially but not exclusively of the superconductors. The papers on characterisation and theory break new ground, particularly in pursuit of new optoelectronic phenomena. The parade of new materials recently synthesised, often containing four or more elements, is surprising. But it is in it reporting of new applications that the book stands out: from circuits to sensors, supermaterials are making their impact on society.

What is a supermaterial? A concise definition is by no means obvious, but a clue can be obtained from the topics discussed here.. In addition to superconductors, the reader will encounter magnetic effects of many kinds, including giant and even colossal ones, organic conductors, photoconductors, and even 400-year-old Japanese ceramics. Processing is a prominent pursuit in supermaterials research, especially but not exclusively of the superconductors. The papers on characterisation and theory break new ground, particularly in pursuit of new optoelectronic phenomena. The parade of new materials recently synthesised, often containing four or more elements, is surprising. But it is in it reporting of new applications that the book stands out: from circuits to sensors, supermaterials are making their impact on society.

The aim of this NATO ASI has been to present an up-to-date overview of current areas of interest in amorphous materials, with particular emphasis on electronic properties and device applications. In order to limit the material to a manageable amount, the meeting was concerned almost exclusively with semiconducting materials. This volume should be regarded as a follow-on to the NATO ASI held in Sozopol, Bulgaria in 1996 and published as "Amorphous Insulators and Semiconductors" edited by M.F. Thorpe and M.1. Mitkova (Kluwer Academic Publishers, NATO ASI series, 3 High Technology - Vol. 23). The lectures and seminars fill the gap between graduate courses and research seminars. The lecturers and seminar speakers were chosen as experts in their respective areas, and the lectures and seminars that were given are presented in this volume. During the first week of the meeting, an emphasis was placed on introductory lectures while the second week focused more on research seminars. There were two very good poster sessions that generated a lot of discussion, but these are not reproduced in this volume as the editors wanted to have only larger contributions to make the proceedings more coherent.

The aim of this NATO ASI has been to present an up-to-date overview of current areas of interest in amorphous materials, with particular emphasis on electronic properties and device applications. In order to limit the material to a manageable amount, the meeting was concerned almost exclusively with semiconducting materials. This volume should be regarded as a follow-on to the NATO ASI held in Sozopol, Bulgaria in 1996 and published as "Amorphous Insulators and Semiconductors" edited by M.F. Thorpe and M.1. Mitkova (Kluwer Academic Publishers, NATO ASI series, 3 High Technology - Vol. 23). The lectures and seminars fill the gap between graduate courses and research seminars. The lecturers and seminar speakers were chosen as experts in their respective areas, and the lectures and seminars that were given are presented in this volume. During the first week of the meeting, an emphasis was placed on introductory lectures while the second week focused more on research seminars. There were two very good poster sessions that generated a lot of discussion, but these are not reproduced in this volume as the editors wanted to have only larger contributions to make the proceedings more coherent.

The state-of-the art of tribology is described, on both macro and micro/nano scales, by internationally recognized scientists working on both fundamental and applied aspects. The history of the subject is covered, followed by instrumentation, basic theories and the latest results on friction, wear, lubrication and industrial applications. Both experimental and computer modelling research are covered, with the emphasis throughout being on applied aspects. The book covers science and engineering topics that are not typically available to students in any structured university curriculum or special course.

The word tribology was fIrst reported in a landmark report by P. Jost in 1966 (Lubrication (Tribology)--A Report on the Present Position and Industry's Needs, Department of Education and Science, HMSO, London). Tribology is the science and technology of two interacting surfaces in relative motion and of related subjects and practices. The popular equivalent is friction, wear and lubrication. The economic impact of the better understanding of tribology of two interacting surfaces in relative motion is known to be immense. Losses resulting from ignorance of tribology amount in the United States alone to about 6 percent of its GNP or about $200 billion dollars per year (1966), and approximately one-third of the world's energy resources in present' use, appear as friction in one form or another. A fundamental understanding of the tribology of the head-medium interface in magnetic recording is crucial to the future growth of the $100 billion per year information storage industry. In the emerging microelectromechanical systems (MEMS) industry, tribology is also recognized as a limiting technology. The advent of new scanning probe microscopy (SPM) techniques (starting with the invention of the scanning tunneling microscope in 1981) to measure surface topography, adhesion, friction, wear, lubricant-fIlm thickness, mechanical properties all on a micro to nanometer scale, and to image lubricant molecules and the availability of supercomputers to conduct atomic-scale simulations has led to the development of a new fIeld referred to as Microtribology, Nanotribology, or Molecular Tribology (see B. Bhushan, J. N. Israelachvili and U.

The particular emphasis of this book is on new approaches to the notch effect problem in fatigue and fracture, and in particular the volumetric approach. These new methods are introduced in an attempt to replace the hot spot method, which suffers from some degree of empiricism. The work has given rise to a new field: notch fracture mechanics, in which a crack is considered as a particular case of a notch. Theoretical and practical aspects are presented in both fracture and fatigue. Special attention is paid to welded joints. This work is particularly recommended to engineers involved in safety design. Readers should possess adequate skill in strength of materials and fracture mechanics.

As Directors of this NATO Workshop, we welcome this opportunity to record formally our thanks to the NATO Scientific Affairs Division for making our meeting possible through generous financial support and encouragement. This meeting has two purposes: the first obvious one because we have collected scientists from East, far East and west to discuss new development in the field of fracture mechanics: the notch fracture mechanics. The second is less obvious but perhaps in longer term more important that is the building of bridges between scientists in the frame of a network called Without Walls Institute on Notch Effects in Fatigue and Fracture". Physical perception of notch effects is not so easy to understand as the presence of a geometrical discontinuity as a worst effect than the simple reduction of cross section. Notch effects in fatigue and fracture is characterised by the following fundamental fact: it is not the maximum local stress or stress which governs the phenomena of fatigue and fracture. The physic shows that a process volume is needed probably to store the necessary energy for starting and propagating the phenomenon. This is a rupture of the traditional "strength of material" school which always give the prior importance of the local maximum stress. This concept of process volume was strongly affirmed during this workshop.

Super-intense laser pulses produce electric field strength peak values of the order of 1016-1018 W/cm2 in the infrared. The interaction of such fields with an atomic system (for example, atom, molecule, cluster), gives rise to highly non-linear processes such as the emission of very fast ions or the production of coherent X-radiation. Such processes have important applications in many different fields, such as biology or nuclear fusion. The latest research in the area is described here, concentrating on: the double ionization of complex atoms; the ionisation and dissociation dynamics of molecules; the interaction of clusters with very intense, femtosecond laser pulses; the production of very intense, coherent short wavelength radiation; stabilization and relativistic effects in super-strong fields; Rydberg atoms and strong field coherent control.

Super-intense laser pulses produce electric field strength peak values of the order of 1016-1018 W/cm2 in the infrared. The interaction of such fields with an atomic system (for example, atom, molecule, cluster), gives rise to highly non-linear processes such as the emission of very fast ions or the production of coherent X-radiation. Such processes have important applications in many different fields, such as biology or nuclear fusion. The latest research in the area is described here, concentrating on: the double ionization of complex atoms; the ionization and dissociation dynamics of molecules; the interaction of clusters with very intense, femtosecond laser pulses; the production of very intense, coherent short wavelength radiation; stabilization and relativistic effects in super-strong fields; Rydberg atoms and strong field coherent control.

Atomically dispersed metal cations and small polyatomic cationic structures co-ordinated to the surface of porous matrices exhibit different properties from the same cationic species contained in a bulk oxide or supported on amorphous carriers. This subject is treated to an extensive review, showing how an understanding of it is essential to the development of a new generation of solid catalysts. There are also opportunities to shape the catalytic properties of the transition metal cations in microporous and mesoporous matrices. The book covers both theoretical and experimental aspects, including the distribution of framework Al atoms in Si-rich zeolites, distribution and siting of charge-exchanged metal cations, electronic, adsorptive and catalytic properties of metal cations, and correlation of metal cation structure and siting with catalytic activity.

Atomically dispersed metal cations and small polyatomic cationic structures co-ordinated to the surface of porous matrices exhibit different properties from the same cationic species contained in a bulk oxide or supported on amorphous carriers. This subject is treated to an extensive review, showing how an understanding of it is essential to the development of a new generation of solid catalysts. There are also exciting opportunities to shape the catalytic properties of the transition metal cations in microporous and mesoporous matrices. The book covers both theoretical and experimental aspects, including the distribution of framework Al atoms in Si-rich zeolites, distribution and siting of charge-exchanged metal cations, electronic, adsorptive and catalytic properties of metal cations, and correlation of metal cation structure and siting with catalytic activity.

This volume contains most of the contributions presented at the NATO Advanced Research Workshop on Rare Earth Transition Metal Borocarbides (Nitrides): Superconducting, Magnetic and Normal State Properties, held in Dresden, Germany at 13 - 18 June 2000. The Workshop was chaired by K. -H. MUller and V. N. Narozhnyi. This was the first meeting specially focused on the quaternary rare-earth transition-metal borocarbides and nitrides - a new class of magnetic superconductors discovered in 1994. The motivation for organizing this workshop was to bring together scientists (both experimentalists and theoreticians), actively working in this field in different countries, using different methods, to exchange their points of view on the properties ofthese materials and to recognize the directions for future research. Totally 48 participants from 17 countries ofEurope, the United States, BraZil, India, Israel and Japan took part in this meeting. In addition about 15 observers (mainly from Germany) attended. The scientific Programme of the Workshop was composed of 7 sections. The section Introduction and Overview was followed by the Electronic Structure and Properties and Phonon Spectra; Magnetic Properties and CEF Effects; Interplay between Superconductivity and Magnetism; Vortex Lattice; Thin Films; Nature of the Superconducting State in Borocarbides sections. Totally 50 presentations were given (45 ofthem in oral form). Considerable attention was devoted to the characterization of the particular place of borocarbides amongst the other magnetic and superconducting systems and, especially, magnetic superconductors.

This volume contains most of the contributions presented at the NATO Advanced Research Workshop on Rare Earth Transition Metal Borocarbides (Nitrides): Superconducting, Magnetic and Normal State Properties, held in Dresden, Germany at 13 - 18 June 2000. The Workshop was chaired by K. -H. MUller and V. N. Narozhnyi. This was the first meeting specially focused on the quaternary rare-earth transition-metal borocarbides and nitrides - a new class of magnetic superconductors discovered in 1994. The motivation for organizing this workshop was to bring together scientists (both experimentalists and theoreticians), actively working in this field in different countries, using different methods, to exchange their points of view on the properties ofthese materials and to recognize the directions for future research. Totally 48 participants from 17 countries ofEurope, the United States, BraZil, India, Israel and Japan took part in this meeting. In addition about 15 observers (mainly from Germany) attended. The scientific Programme of the Workshop was composed of 7 sections. The section Introduction and Overview was followed by the Electronic Structure and Properties and Phonon Spectra; Magnetic Properties and CEF Effects; Interplay between Superconductivity and Magnetism; Vortex Lattice; Thin Films; Nature of the Superconducting State in Borocarbides sections. Totally 50 presentations were given (45 ofthem in oral form). Considerable attention was devoted to the characterization of the particular place of borocarbides amongst the other magnetic and superconducting systems and, especially, magnetic superconductors.

In the last decade it has become increasingly evident that strong correla- tions between electrons are an essential and unifying factor in such diverse phenomena within solid state physics as high-temperature superconductivity, colossal magnetoresistance, the quantum Hall effect, heavy-fermion metals and Coulomb blockade in single-electron transistors. A new paradigmofnon- FermiLiquidbehaviourisalsoemergingand, inanumberofsystems, replacing the Fermi liquid, which has been the cornerstone ofthe physics of metals and superconductors for the pastdecades. In spite of major achievements, the theoretical studies and understanding of strongly-correlated electrons seems to be still in its infancy. Anomalous electron properties have been studied in some generic models of correlated electrons, such as the Hubbard and t-J models, the Anderson and Kondo impurity models, and their lattice equivalents. New insights into the behaviour of these, and related models is emerging from the introduction of powerful numerical methods to study such many-body models, including approximate techniquesofmany-body theory and exactresults inlow-andhigh-dimensional systems.Theseall showconvincingevidenceforbreakdownoftheFermiliquid concept. The Bled workshop focused on several major open questions in the theory of anomalous metals with correlated electrons. These theoretical advances were complemented by the latest experimental results in related materials, presented by leading experimentalists in the field. The main emphasis was on the following topics: - physics ofcuprates and high-temperature superconductors, - charge- and spin-ordering and fluctuations, - manganites and colossal magnetoresistance, - low-dimensional systems and transport, - Mott-Hubbard transition and infinite dimensional systems, - quantum Hall effect.

In the last decade it has become increasingly evident that strong correla- tions between electrons are an essential and unifying factor in such diverse phenomena within solid state physics as high-temperature superconductivity, colossal magnetoresistance, the quantum Hall effect, heavy-fermion metals and Coulomb blockade in single-electron transistors. A new paradigmofnon- FermiLiquidbehaviourisalsoemergingand, inanumberofsystems, replacing the Fermi liquid, which has been the cornerstone ofthe physics of metals and superconductors for the pastdecades. In spite of major achievements, the theoretical studies and understanding of strongly-correlated electrons seems to be still in its infancy. Anomalous electron properties have been studied in some generic models of correlated electrons, such as the Hubbard and t-J models, the Anderson and Kondo impurity models, and their lattice equivalents. New insights into the behaviour of these, and related models is emerging from the introduction of powerful numerical methods to study such many-body models, including approximate techniquesofmany-body theory and exactresults inlow-andhigh-dimensional systems.Theseall showconvincingevidenceforbreakdownoftheFermiliquid concept. The Bled workshop focused on several major open questions in the theory of anomalous metals with correlated electrons. These theoretical advances were complemented by the latest experimental results in related materials, presented by leading experimentalists in the field. The main emphasis was on the following topics: - physics ofcuprates and high-temperature superconductors, - charge- and spin-ordering and fluctuations, - manganites and colossal magnetoresistance, - low-dimensional systems and transport, - Mott-Hubbard transition and infinite dimensional systems, - quantum Hall effect.