Atoms in solids

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  • Innovation in engineering often means the clever use of a new material - new to a particular application, but not necessarily (although sometimes) new in the sense of ‘recently developed’. Plastic paper clips and ceramic turbine-blades both represent attempts to do better with polymers and ceramics what had previously been done well with metals. And engineering disasters are frequently caused by the misuse of materials.

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  • Diffusion is the transport of matter from one point to another by thermal motion of atoms or molecules. It is relatively fast in gases, slow in liquids, and very slow in solids. Diffusion plays a key rˆole in many processes as diverse as intermixing of gases and liquids, permeation of atoms or molecules through membranes, evaporation of liquids, drying of timber, doping silicon wafers to make semiconductor devices, and transport of thermal neutrons in nuclear power reactors.

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  • To have a quantum-mechanical treatment we model a crystalline solid as matter in which the atoms have long-range order, that is a recurring (periodical) pattern of atomic positions that extends over many atoms. We will describe the wavefunctions and energy levels of electrons in such periodical atomic structures.  We want to answer the question: Why do some solids conduct curr We want to answer the question: Why do some solids conduct current ent and others don and others don’ ’t? t?...

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  • The new millennium has seen the birth of a new perspective that conflates research in solid-state physics, biological science as well as materials engineering. The perspective is one that recognizes that future new advances in all these areas will be based on a fundamental understanding of the atomic and molecular infrastructure of materials that has resulted from two centuries of chemistry. Major advances will be achieved when the novel behavior, in particular the quantum mechanical behavior, that nanoscale structures possess, can be controlled and harnessed....

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  • The state-of-the-art of controlled radical polymerization (CRP) in 2011 is presented. Atom transfer radical polymerization, stable radical mediated polymerization, and degenerate transfer processes, including reversible addition fragmentation chain transfer are the most often used CRP procedures. CRP opens new avenues to novel materials from a large range of monomers. Detailed structure-reactivity relationships and mechanistic understanding not only helps attain a better controlled polymerization but enables preparation of polymers with complex architectures.

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  • Surface effects in film coating Michael E.Aulton SUMMARY This chapter will explain the significance of the stages of impingement, wetting, spreading and penetration of atomized droplets at the surface of tablet or multiparticulate cores. It will explain some of the fundamental aspects of solid-liquid interfaces which are important to the process of film coating. This chapter will emphasize the importance of controlling the ‘wetting power’ of the spray and the ‘wettability’ of the substrate, and will explain how this can be achieved by changes in formulation and process parameters.

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  • Lasers continue to be an amazingly robust field of activity, one of continually expanding scientific and technological frontiers.

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  • Quantum mechanics, shortly after invention, obtained applications in different area of human knowledge. Perhaps, the most attractive feature of quantum mechanics is its applications in such diverse area as, astrophysics, nuclear physics, atomic and molecular spectroscopy, solid state physics and nanotechnology, crystallography, chemistry, biotechnology, information theory, electronic engineering...

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  • Most colleges and universities now have courses and degree programs related to materials science. Materials Chemistry addresses inorganic, organic, and nanobased materials from a structure vs. property treatment, providing a suitable breadth and depth coverage of the rapidly evolving materials field in a concise format.

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  • Effects of Structure on Properties Physical properties of metals, ceramics, and polymers, such as ductility, thermal expansion, heat capacity, elastic modulus, electrical conductivity, and dielectric and magnetic properties, are a direct result of the structure and bonding of the atoms and ions in the

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  • Amorphous materials have attracted much attention in the last two decades. The first reason for this is their potential industrial applications as suitable materials for fabricating devices, and the second reason is the lack of understanding of many properties of these materials, which are very different from those of crystalline materials. Some of their properties are different even from one sample to another of the same material.

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  • Whatever the context, be it solid, liquid, or some transitionary setting, materials science seeks an understanding of a material's macromolecular structure and properties by drawing on knowledge of its atomic and molecular constituents. Until recently, the term ''materials science'' was used primarily to denote empirical study, fundamental research, synthesis, a

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  • Simulation of the diffusion mechanism via microscopic bubbles in amorphous materials is carried out using the statistical relaxation models $Co_{81.5}B_{18.5}$ containing $2\times 10^5$ atoms. The present work is focused on the role of these bubbles for self-diffusion in amorphous solids. It was found that the numbers of the vacancy bubbles in amorphous $Co_{81.5}B_{18.5}$ vary from $1.4\times 10^{-3}$ to $4\times 10^{-3}$ per atom depending on the relaxation degree. The simulation shows the collective character of the atomic movement upon diffusion atoms moving.

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  • Metals are used as biomaterials due to their excellent electrical and thermal conductivity and mechanical properties. Since some electrons are independent in metals, they can quickly transfer an electric charge and thermal energy. The mobile free electrons act as the binding force to hold the positive metal ions together. This attraction is strong, as evidenced by the closely packed atomic arrangement resulting in high specific gravity and high melting points of most metals.

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  • Carbon T Takamura, Harbin Institute of Technology, Harbin, China & 2009 Elsevier B.V. All rights reserved. Physical and Chemical Properties of Carbon Families Morphology of Carbon Carbon is solid under ambient temperature and pressure and there are four allotropes: diamond, graphite, nanotubes and fullerenes, and carbynes, and in addition, there are many morphologies including amorphous carbons, glass-like carbons, porous carbons, and so on.

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  • Chemical reactions (abiotic reactions) are “classical” chemical reactions that are not mediated by bacteria. They may include reaction processes such as precipitation, hydrolysis, complexation, elimination, substitution etc. that transform chemicals to other chemicals and potentially alter their phase/state (solid, liquid, gas, dissolved). Precipitation is the removal of ions from solution by the formation of insoluble compounds, i.e. a solid-phase precipitate. Hydrolysis is a process of chemical reaction by the addition of water.

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  • Photons interact with matter because matter contains electric charges. The electric field of light exerts forces on the electric charges and dipoles in atoms, molecules, and solids, causing them to vibrate or accelerate. Conversely,

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  • CHAPTER 7 SOLID MATERIALS Joseph Datsko Professor Emeritus of Mechanical Engineering The University of Michigan Ann Arbor, Michigan 7.1 STRUCTURE OF SOLIDS / 7.1 7.2 ATOMIC BONDING FORCES / 7.2 7.3 ATOMIC STRUCTURES / 7.4 7.4 CRYSTAL IMPERFECTIONS / 7.11 7.5 SLIP IN CRYSTALLINE SOLIDS / 7.15 7.6 MECHANICAL STRENGTH / 7.17 7.7 MECHANICAL PROPERTIES AND TESTS / 7.20 7.8 HARDNESS / 7.21 7.9 THE TENSILE TEST / 7.25 7.10 TENSILE PROPERTIES / 7.32 7.11 STRENGTH, STRESS, AND STRAIN RELATIONS / 7.36 7.12 IMPACT STRENGTH / 7.42 7.13 CREEP STRENGTH / 7.43 7.14 MECHANICAL-PROPERTY DATA / 7.46 7.

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  • 495 Nanotribol Part C Nanotribology and Nanomechanics 17 Micro/Nanotribology and Materials Characterization Studies Using Scanning Probe Microscopy Bharat Bhushan, Columbus, USA 18 Surface Forces and Nanorheology of Molecularly Thin Films Marina Ruths, Åbo, Finland Alan D. Berman, Los Angeles, USA Jacob N. Israelachvili, Santa Barbara, USA 19 Scanning Probe Studies of Nanoscale Adhesion Between Solids in the Presence of Liquids and Monolayer Films Robert W. Carpick, Madison, USA James D.

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  • The invention of scanning tunneling microscope (STM) by Binnig and his colleagues in 1982 opened up the possibility of imaging material surfaces with spatial resolution much superior to the conventional microscopy techniques. The STM is the first instrument capable of directly obtaining three-dimensional images of solid surfaces with atomic resolution. Even though STM is capable of achieving atomic resolution, it can only be used on electrical conductors. This limitation has led to the invention of atomic force microscope (AFM) by Binnig and his co-workers in 1986.

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