C. Mathew Mate
- Published in print:
- 2007
- Published Online:
- January 2008
- ISBN:
- 9780198526780
- eISBN:
- 9780191712098
- Item type:
- book
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198526780.001.0001
- Subject:
- Physics, Condensed Matter Physics / Materials
Friction, lubrication, adhesion, and wear are prevalent physical phenomena in everyday life and in many key technologies. This book incorporates a bottom-up approach to friction, lubrication, and ...
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Friction, lubrication, adhesion, and wear are prevalent physical phenomena in everyday life and in many key technologies. This book incorporates a bottom-up approach to friction, lubrication, and wear. This is done by focusing on how these tribological phenomena occur on the small scale — the atomic to the micrometer scale — a field often called nanotribology. The book covers the microscopic origins of the common tribological concepts of roughness, elasticity, plasticity, friction coefficients, and wear coefficients. Some macroscale concepts (like elasticity) scale down well to the micro- and atomic-scale, while other macroscale concepts (like hydrodynamic lubrication) do not. In addition, this book also has chapters on topics not typically found in tribology texts: surface energy, surface forces, lubrication in confined spaces, and the atomistic origins of friction. These chapters cover tribological concepts that have become increasingly important at the small scale: capillary condensation, disjoining pressure, contact electrification, molecular slippage at interfaces, and atomic scale stick-slip. Numerous examples are provided throughout the book on how a nanoscale understanding of tribological phenomena is essential to the proper engineering of important new technologies such as MEMS, disk drives, and nanoimprinting.Less
Friction, lubrication, adhesion, and wear are prevalent physical phenomena in everyday life and in many key technologies. This book incorporates a bottom-up approach to friction, lubrication, and wear. This is done by focusing on how these tribological phenomena occur on the small scale — the atomic to the micrometer scale — a field often called nanotribology. The book covers the microscopic origins of the common tribological concepts of roughness, elasticity, plasticity, friction coefficients, and wear coefficients. Some macroscale concepts (like elasticity) scale down well to the micro- and atomic-scale, while other macroscale concepts (like hydrodynamic lubrication) do not. In addition, this book also has chapters on topics not typically found in tribology texts: surface energy, surface forces, lubrication in confined spaces, and the atomistic origins of friction. These chapters cover tribological concepts that have become increasingly important at the small scale: capillary condensation, disjoining pressure, contact electrification, molecular slippage at interfaces, and atomic scale stick-slip. Numerous examples are provided throughout the book on how a nanoscale understanding of tribological phenomena is essential to the proper engineering of important new technologies such as MEMS, disk drives, and nanoimprinting.
Victor F. Petrenko and Robert W. Whitworth
- Published in print:
- 2002
- Published Online:
- February 2010
- ISBN:
- 9780198518945
- eISBN:
- 9780191707247
- Item type:
- book
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198518945.001.0001
- Subject:
- Physics, Crystallography: Physics
Ice is one of the most abundant and environmentally important materials on Earth, and its unique and intriguing physical properties present fascinating areas of study. This book takes as its subject ...
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Ice is one of the most abundant and environmentally important materials on Earth, and its unique and intriguing physical properties present fascinating areas of study. This book takes as its subject the physics of ice: the properties of the material itself and the ways in which these properties are interpreted in terms of water molecules and crystalline structure. Although ice has a simple crystal structure its hydrogen bonding results in unique properties, which continue to be the subject of active research. An understanding of these properties is essential in fields such as glaciology, ice mechanics, ice adhesion, the dating of ice cores in Antarctica and Greenland, meteorology, thunderstorm electricity, and the study of comets or the icy moons of the outer planets in the solar system. In this book the physical principles underlying the properties of ice are carefully developed. Much work on important topics such as the current understanding of the electrical, mechanical, and surface properties of ice, or the occurrence of many different crystalline phases, are developed.Less
Ice is one of the most abundant and environmentally important materials on Earth, and its unique and intriguing physical properties present fascinating areas of study. This book takes as its subject the physics of ice: the properties of the material itself and the ways in which these properties are interpreted in terms of water molecules and crystalline structure. Although ice has a simple crystal structure its hydrogen bonding results in unique properties, which continue to be the subject of active research. An understanding of these properties is essential in fields such as glaciology, ice mechanics, ice adhesion, the dating of ice cores in Antarctica and Greenland, meteorology, thunderstorm electricity, and the study of comets or the icy moons of the outer planets in the solar system. In this book the physical principles underlying the properties of ice are carefully developed. Much work on important topics such as the current understanding of the electrical, mechanical, and surface properties of ice, or the occurrence of many different crystalline phases, are developed.
C. Mathew Mate
- Published in print:
- 2007
- Published Online:
- January 2008
- ISBN:
- 9780198526780
- eISBN:
- 9780191712098
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198526780.003.0005
- Subject:
- Physics, Condensed Matter Physics / Materials
The energies associated with surfaces — surface energy, interfacial energy, surface tension, and work of adhesion — drive many surface phenomena including tribological ones such as adhesion and ...
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The energies associated with surfaces — surface energy, interfacial energy, surface tension, and work of adhesion — drive many surface phenomena including tribological ones such as adhesion and friction. This chapter discusses the physical origins of surface energies for liquids and solids, and how the concepts of capillary pressure, capillary condensation, wetting, and work of adhesion are derived from surface energy. Further, this chapter covers the different methods for measuring surface energies, including a thorough discussion of the most common method to measure the surface energy of solids: contact angle measurements of liquid droplets on surfaces. The chapter also introduces how surface energies and surface tensions lead to adhesion and adhesion hysteresis between contacting surfaces, which is followed up in the subsequent chapters on surface forces.Less
The energies associated with surfaces — surface energy, interfacial energy, surface tension, and work of adhesion — drive many surface phenomena including tribological ones such as adhesion and friction. This chapter discusses the physical origins of surface energies for liquids and solids, and how the concepts of capillary pressure, capillary condensation, wetting, and work of adhesion are derived from surface energy. Further, this chapter covers the different methods for measuring surface energies, including a thorough discussion of the most common method to measure the surface energy of solids: contact angle measurements of liquid droplets on surfaces. The chapter also introduces how surface energies and surface tensions lead to adhesion and adhesion hysteresis between contacting surfaces, which is followed up in the subsequent chapters on surface forces.
A.D. Neate and A. Truman
- Published in print:
- 2008
- Published Online:
- September 2008
- ISBN:
- 9780199239252
- eISBN:
- 9780191716911
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199239252.003.0013
- Subject:
- Mathematics, Probability / Statistics, Analysis
This chapter summarises a selection of results on the inviscid limit of the stochastic Burgers equation emphasising geometric properties of the caustic, Maxwell set and Hamilton-Jacobi level surfaces ...
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This chapter summarises a selection of results on the inviscid limit of the stochastic Burgers equation emphasising geometric properties of the caustic, Maxwell set and Hamilton-Jacobi level surfaces and relating these results to a discussion of stochastic turbulence. It shows that for small viscosities there exists a vortex filament structure near to the Maxwell set. It is discussed how this vorticity is directly related to the adhesion model for the evolution of the early universe, and new explicit formulas for the distribution of mass within the shock are included.Less
This chapter summarises a selection of results on the inviscid limit of the stochastic Burgers equation emphasising geometric properties of the caustic, Maxwell set and Hamilton-Jacobi level surfaces and relating these results to a discussion of stochastic turbulence. It shows that for small viscosities there exists a vortex filament structure near to the Maxwell set. It is discussed how this vorticity is directly related to the adhesion model for the evolution of the early universe, and new explicit formulas for the distribution of mass within the shock are included.
Andrew Biewener and Sheila Patek
- Published in print:
- 2018
- Published Online:
- May 2018
- ISBN:
- 9780198743156
- eISBN:
- 9780191803031
- Item type:
- book
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/oso/9780198743156.001.0001
- Subject:
- Biology, Animal Biology, Ecology
This book provides a synthesis of the physical, physiological, evolutionary, and biomechanical principles that underlie animal locomotion. An understanding and full appreciation of animal locomotion ...
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This book provides a synthesis of the physical, physiological, evolutionary, and biomechanical principles that underlie animal locomotion. An understanding and full appreciation of animal locomotion requires the integration of these principles. Toward this end, we provide the necessary introductory foundation that will allow a more in-depth understanding of the physical biology and physiology of animal movement. In so doing, we hope that this book will illuminate the fundamentals and breadth of these systems, while inspiring our readers to look more deeply into the scientific literature and investigate new features of animal movement. Several themes run through this book. The first is that by comparing the modes and mechanisms by which animals have evolved the capacity for movement, we can understand the common principles that underlie each mode of locomotion. A second is that size matters. One of the most amazing aspects of biology is the enormous spatial and temporal scale over which organisms and biological processes operate. Within each mode of locomotion, animals have evolved designs and mechanisms that effectively contend with the physical properties and forces imposed on them by their environment. Understanding the constraints of scale that underlie locomotor mechanisms is essential to appreciating how these mechanisms have evolved and how they operate. A third theme is the importance of taking an integrative and comparative evolutionary approach in the study of biology. Organisms share much in common. Much of their molecular and cellular machinery is the same. They also must navigate similar physical properties of their environment. Consequently, an integrative approach to organismal function that spans multiple levels of biological organization provides a strong understanding of animal locomotion. By comparing across species, common principles of design emerge. Such comparisons also highlight how certain organisms may differ and point to strategies that have evolved for movement in diverse environments. Finally, because convergence upon common designs and the generation of new designs result from historical processes governed by natural selection, it is also important that we ask how and why these systems have evolved.Less
This book provides a synthesis of the physical, physiological, evolutionary, and biomechanical principles that underlie animal locomotion. An understanding and full appreciation of animal locomotion requires the integration of these principles. Toward this end, we provide the necessary introductory foundation that will allow a more in-depth understanding of the physical biology and physiology of animal movement. In so doing, we hope that this book will illuminate the fundamentals and breadth of these systems, while inspiring our readers to look more deeply into the scientific literature and investigate new features of animal movement. Several themes run through this book. The first is that by comparing the modes and mechanisms by which animals have evolved the capacity for movement, we can understand the common principles that underlie each mode of locomotion. A second is that size matters. One of the most amazing aspects of biology is the enormous spatial and temporal scale over which organisms and biological processes operate. Within each mode of locomotion, animals have evolved designs and mechanisms that effectively contend with the physical properties and forces imposed on them by their environment. Understanding the constraints of scale that underlie locomotor mechanisms is essential to appreciating how these mechanisms have evolved and how they operate. A third theme is the importance of taking an integrative and comparative evolutionary approach in the study of biology. Organisms share much in common. Much of their molecular and cellular machinery is the same. They also must navigate similar physical properties of their environment. Consequently, an integrative approach to organismal function that spans multiple levels of biological organization provides a strong understanding of animal locomotion. By comparing across species, common principles of design emerge. Such comparisons also highlight how certain organisms may differ and point to strategies that have evolved for movement in diverse environments. Finally, because convergence upon common designs and the generation of new designs result from historical processes governed by natural selection, it is also important that we ask how and why these systems have evolved.
JAMES L. SALZER
- Published in print:
- 1995
- Published Online:
- May 2009
- ISBN:
- 9780195082937
- eISBN:
- 9780199865802
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195082937.003.0008
- Subject:
- Neuroscience, Disorders of the Nervous System
This chapter discusses the structural features of cell adhesion molecules (CAMs) and their role in axonal-glial interactions of myelination and nerve fiber outgrowth. CAMs mediate many of the ...
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This chapter discusses the structural features of cell adhesion molecules (CAMs) and their role in axonal-glial interactions of myelination and nerve fiber outgrowth. CAMs mediate many of the morphogenetic events that occur during nerve fiber outgrowth, ensheathment, and myelination. Dramatic changes in the expression of these molecules accompany and are likely to underlie these complex developmental processes. The molecular mechanisms by which these molecules regulate these events probably involve reorganization of the cytoskeleton and intracellular signaling events, but they remain little understood.Less
This chapter discusses the structural features of cell adhesion molecules (CAMs) and their role in axonal-glial interactions of myelination and nerve fiber outgrowth. CAMs mediate many of the morphogenetic events that occur during nerve fiber outgrowth, ensheathment, and myelination. Dramatic changes in the expression of these molecules accompany and are likely to underlie these complex developmental processes. The molecular mechanisms by which these molecules regulate these events probably involve reorganization of the cytoskeleton and intracellular signaling events, but they remain little understood.
C. Mathew Mate
- Published in print:
- 2007
- Published Online:
- January 2008
- ISBN:
- 9780198526780
- eISBN:
- 9780191712098
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198526780.003.0006
- Subject:
- Physics, Condensed Matter Physics / Materials
As it is more practical to measure the forces acting between two contacting surfaces then the energies of surfaces, this chapter covers those surface forces that are derived from surface energies. ...
More
As it is more practical to measure the forces acting between two contacting surfaces then the energies of surfaces, this chapter covers those surface forces that are derived from surface energies. The starting point is Derjaguin's approximation, which relates the energy between two flat surfaces to other geometries: sphere/flat, sphere/sphere, and crossed cylinders. Next is a discussion of the surface forces in dry contacts with no liquid menisci around the contact points. This discussion covers the cases where adhesion causes deformation (JKR theory) and where deformation is insignificant (DMT theory). The second half of this chapter deals with how liquid menisci around contacts contribute to adhesion forces, both for sphere on flat geometries and for contacting rough surfaces.Less
As it is more practical to measure the forces acting between two contacting surfaces then the energies of surfaces, this chapter covers those surface forces that are derived from surface energies. The starting point is Derjaguin's approximation, which relates the energy between two flat surfaces to other geometries: sphere/flat, sphere/sphere, and crossed cylinders. Next is a discussion of the surface forces in dry contacts with no liquid menisci around the contact points. This discussion covers the cases where adhesion causes deformation (JKR theory) and where deformation is insignificant (DMT theory). The second half of this chapter deals with how liquid menisci around contacts contribute to adhesion forces, both for sphere on flat geometries and for contacting rough surfaces.
Nasr M. Ghoniem and Daniel D. Walgraef
- Published in print:
- 2008
- Published Online:
- May 2008
- ISBN:
- 9780199298686
- eISBN:
- 9780191720222
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199298686.003.0016
- Subject:
- Physics, Condensed Matter Physics / Materials
This chapter presents the theory of laser-induced deformation and patterning of irradiated surfaces. Topics discussed include laser irradiation and thin film deformation, laser-induced temperature ...
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This chapter presents the theory of laser-induced deformation and patterning of irradiated surfaces. Topics discussed include laser irradiation and thin film deformation, laser-induced temperature distribution, vacancy dynamics in strained crystals, deformation equations for thin films, variational principle for the free energy, deformation instability and surface patterning, and the influence of crystal anisotropy and adhesion.Less
This chapter presents the theory of laser-induced deformation and patterning of irradiated surfaces. Topics discussed include laser irradiation and thin film deformation, laser-induced temperature distribution, vacancy dynamics in strained crystals, deformation equations for thin films, variational principle for the free energy, deformation instability and surface patterning, and the influence of crystal anisotropy and adhesion.
Jin Huang, Ning Lin, Yun Chen, Peter R. Chang, and Jiahui Yu
- Published in print:
- 2011
- Published Online:
- September 2011
- ISBN:
- 9780199581924
- eISBN:
- 9780191728853
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199581924.003.0011
- Subject:
- Physics, Condensed Matter Physics / Materials
The incorporation of nanofillers into soy protein materials significantly enhances tensile strength and modulus, and in some cases, contributes to a simultaneous increase in strength and elongation. ...
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The incorporation of nanofillers into soy protein materials significantly enhances tensile strength and modulus, and in some cases, contributes to a simultaneous increase in strength and elongation. The decrease in tensile strength that results from plasticization, is therefore, to some extent recovered. Water absorption usually decreased with the incorporation of nanofillers. In addition, the unique properties of some nanofillers such as the electron conductivity of carbon nanotubes and the antiflammability of layered silicates, can be transplanted into soy protein based nanocomposites. The nanocomposite shows great potential for partly solving the two prevailing problems of low strength and water sensitivity, which greatly hamper the development and application of soy protein based plastics. It also contributes to the development of high performance/novel functionality soy protein based materials. Contrary to most cases with soy protein as matrix, one recent study focused on applying soy protein nanoparticle aggregates to modify styrene-butadiene elastomer. The results showed that compact soy protein nanoparticle aggregates interacted more strongly with the polymer matrix and dispersed more uniformly than crude soy protein, and hence produced better modulus retention for the nanocomposites. Without doubt, soy protein based fibres (such as textiles) and adhesives can be further improved in terms of mechanical or adhesion performance by incorporating the proper nanofiller. The single most important factor affecting the high performance of soy protein based nanocomposites is strengthening the interfacial adhesion between the soy protein matrix and nanofillers. Chemical modification on the nanofiller surface is expected to improve the miscibility between filler and soy protein matrix. Furthermore, grafted long polymer chains may penetrate the soy protein matrix to produce a “co-continuous phase” structure, where the interactions and entanglements between grafted polymer chains and soy protein chains contribute to stronger interfacial adhesion.Less
The incorporation of nanofillers into soy protein materials significantly enhances tensile strength and modulus, and in some cases, contributes to a simultaneous increase in strength and elongation. The decrease in tensile strength that results from plasticization, is therefore, to some extent recovered. Water absorption usually decreased with the incorporation of nanofillers. In addition, the unique properties of some nanofillers such as the electron conductivity of carbon nanotubes and the antiflammability of layered silicates, can be transplanted into soy protein based nanocomposites. The nanocomposite shows great potential for partly solving the two prevailing problems of low strength and water sensitivity, which greatly hamper the development and application of soy protein based plastics. It also contributes to the development of high performance/novel functionality soy protein based materials. Contrary to most cases with soy protein as matrix, one recent study focused on applying soy protein nanoparticle aggregates to modify styrene-butadiene elastomer. The results showed that compact soy protein nanoparticle aggregates interacted more strongly with the polymer matrix and dispersed more uniformly than crude soy protein, and hence produced better modulus retention for the nanocomposites. Without doubt, soy protein based fibres (such as textiles) and adhesives can be further improved in terms of mechanical or adhesion performance by incorporating the proper nanofiller. The single most important factor affecting the high performance of soy protein based nanocomposites is strengthening the interfacial adhesion between the soy protein matrix and nanofillers. Chemical modification on the nanofiller surface is expected to improve the miscibility between filler and soy protein matrix. Furthermore, grafted long polymer chains may penetrate the soy protein matrix to produce a “co-continuous phase” structure, where the interactions and entanglements between grafted polymer chains and soy protein chains contribute to stronger interfacial adhesion.
G. A. D. Briggs and O. V. Kolosov
- Published in print:
- 2009
- Published Online:
- February 2010
- ISBN:
- 9780199232734
- eISBN:
- 9780191716355
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199232734.003.0009
- Subject:
- Physics, Condensed Matter Physics / Materials
Biological tissue: The elastic properties of biological tissue show much greater contrast than their optical properties. Cells can be imaged in an aqueous medium, so that the ...
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Biological tissue: The elastic properties of biological tissue show much greater contrast than their optical properties. Cells can be imaged in an aqueous medium, so that the variation with environment and time of their mechanical properties and adhesion to a substrate can be measured. For soft tissue, time‐resolved techniques are more relevant than Rayleigh wave interference. Mineralized tissues such as teeth can support Rayleigh waves, giving contrast from carious lesions and allowing line‐focus‐beam V(z) analysis to measure elastic anisotropy. Bone is an intermediate case, with contrast from its mechanical structure.Less
Biological tissue: The elastic properties of biological tissue show much greater contrast than their optical properties. Cells can be imaged in an aqueous medium, so that the variation with environment and time of their mechanical properties and adhesion to a substrate can be measured. For soft tissue, time‐resolved techniques are more relevant than Rayleigh wave interference. Mineralized tissues such as teeth can support Rayleigh waves, giving contrast from carious lesions and allowing line‐focus‐beam V(z) analysis to measure elastic anisotropy. Bone is an intermediate case, with contrast from its mechanical structure.
G. A. D. Briggs and O. V. Kolosov
- Published in print:
- 2009
- Published Online:
- February 2010
- ISBN:
- 9780199232734
- eISBN:
- 9780191716355
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199232734.003.0010
- Subject:
- Physics, Condensed Matter Physics / Materials
Some layered structures offer separate reflections from adjacent surfaces. In this way interior imaging of semiconductor devices allows failure analysis before opening up the packaging. This can be ...
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Some layered structures offer separate reflections from adjacent surfaces. In this way interior imaging of semiconductor devices allows failure analysis before opening up the packaging. This can be considered as a kind of high resolution non‐destructive testing, and may prove to be the widest industrial use of acoustic microscopy. Laminated polymer coatings can be imaged by separating the reflections. Layered structures can also be studied through the effect on V(z) of the layers on waves propagating parallel to the surface, either in a plate mode or perturbing the propagation of Rayleigh waves. Adhesion can be observed only through its effect on elastic properties. Some layers can be studied in section, revealing effects of anisotropy and scattering of Rayleigh waves.Less
Some layered structures offer separate reflections from adjacent surfaces. In this way interior imaging of semiconductor devices allows failure analysis before opening up the packaging. This can be considered as a kind of high resolution non‐destructive testing, and may prove to be the widest industrial use of acoustic microscopy. Laminated polymer coatings can be imaged by separating the reflections. Layered structures can also be studied through the effect on V(z) of the layers on waves propagating parallel to the surface, either in a plate mode or perturbing the propagation of Rayleigh waves. Adhesion can be observed only through its effect on elastic properties. Some layers can be studied in section, revealing effects of anisotropy and scattering of Rayleigh waves.
Victor F. Petrenko and Robert W. Whitworth
- Published in print:
- 2002
- Published Online:
- February 2010
- ISBN:
- 9780198518945
- eISBN:
- 9780191707247
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198518945.003.0013
- Subject:
- Physics, Crystallography: Physics
This chapter first discusses experiments on the adhesion of ice to other materials, which presents very real practical problems in cold climates. It then considers the low coefficient of friction for ...
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This chapter first discusses experiments on the adhesion of ice to other materials, which presents very real practical problems in cold climates. It then considers the low coefficient of friction for objects like skates sliding on ice. This is due to a thin film of liquid, produced not by pressure melting but by local heating.Less
This chapter first discusses experiments on the adhesion of ice to other materials, which presents very real practical problems in cold climates. It then considers the low coefficient of friction for objects like skates sliding on ice. This is due to a thin film of liquid, produced not by pressure melting but by local heating.
C. Mathew Mate and Robert W. Carpick
- Published in print:
- 2019
- Published Online:
- October 2019
- ISBN:
- 9780199609802
- eISBN:
- 9780191747724
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/oso/9780199609802.003.0006
- Subject:
- Physics, Condensed Matter Physics / Materials, Atomic, Laser, and Optical Physics
As it more practical to measure the forces acting between two contacting surfaces then the energies of surfaces, this chapter covers those surface forces that are derived from surface energies. The ...
More
As it more practical to measure the forces acting between two contacting surfaces then the energies of surfaces, this chapter covers those surface forces that are derived from surface energies. The starting point is Derjaguin’s approximation, which relates the energy between two flat surfaces to the force in other geometries: sphere/flat, sphere/sphere, and crossed cylinders. Next is a discussion of the surface forces in dry contacts with no liquid menisci around the contact points. This discussion covers the cases where adhesion causes significant deformation (JKR theory), where deformation is insignificant (DMT theory), and the cases in between. How surface roughness impacts adhesion is also discussed. The second half of this chapter deals with how liquid menisci around contacts contribute to adhesion forces, both for the sphere-on-flat geometry and for contacting rough surfaces.Less
As it more practical to measure the forces acting between two contacting surfaces then the energies of surfaces, this chapter covers those surface forces that are derived from surface energies. The starting point is Derjaguin’s approximation, which relates the energy between two flat surfaces to the force in other geometries: sphere/flat, sphere/sphere, and crossed cylinders. Next is a discussion of the surface forces in dry contacts with no liquid menisci around the contact points. This discussion covers the cases where adhesion causes significant deformation (JKR theory), where deformation is insignificant (DMT theory), and the cases in between. How surface roughness impacts adhesion is also discussed. The second half of this chapter deals with how liquid menisci around contacts contribute to adhesion forces, both for the sphere-on-flat geometry and for contacting rough surfaces.
Michel Labouesse
- Published in print:
- 2011
- Published Online:
- September 2011
- ISBN:
- 9780199605835
- eISBN:
- 9780191729522
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199605835.003.0011
- Subject:
- Physics, Soft Matter / Biological Physics
Embryonic morphogenesis refers to the stages during which embryos and their organs acquire their functional structure. It requires groups of cells with similar properties to organize themselves in ...
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Embryonic morphogenesis refers to the stages during which embryos and their organs acquire their functional structure. It requires groups of cells with similar properties to organize themselves in space and adopt distinctive shapes. The physical mechanisms that control cell dynamics during that time are slowly beginning to emerge from the study of a few simple systems. This chapter presents some examples outlining the current understanding of cell mechanics from the physics point of view, emphasizing the balance between cortical tension and cell adhesion, the behaviour of motors, and the response to tension. It also outlines how modelling is gaining prominence.Less
Embryonic morphogenesis refers to the stages during which embryos and their organs acquire their functional structure. It requires groups of cells with similar properties to organize themselves in space and adopt distinctive shapes. The physical mechanisms that control cell dynamics during that time are slowly beginning to emerge from the study of a few simple systems. This chapter presents some examples outlining the current understanding of cell mechanics from the physics point of view, emphasizing the balance between cortical tension and cell adhesion, the behaviour of motors, and the response to tension. It also outlines how modelling is gaining prominence.
Luigi Preziosi and Guido Vitale
- Published in print:
- 2011
- Published Online:
- September 2011
- ISBN:
- 9780199605835
- eISBN:
- 9780191729522
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199605835.003.0007
- Subject:
- Physics, Soft Matter / Biological Physics
This chapter provides the basics to deduce multiphase models for the essential constituents present in tumours (cells, extracellular matrix, extracellular liquid, and possibly blood and limphatic ...
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This chapter provides the basics to deduce multiphase models for the essential constituents present in tumours (cells, extracellular matrix, extracellular liquid, and possibly blood and limphatic vasculature). All the steps of the modelling procedure are explained in detail, special attention being paid to the meaning of all the different terms involved in the model. The chapter focuses on several mechanical aspects related to tumour growth, e.g., the activation of mechanotransduction pathways inside the cell, contact inhibition phenomena, the formation of stiffer fibrotic tissues, the adhesion phenomena characterizing the mechanical interaction between cells and between cell and extracellular matrix, and cell re-organization within the tissue.Less
This chapter provides the basics to deduce multiphase models for the essential constituents present in tumours (cells, extracellular matrix, extracellular liquid, and possibly blood and limphatic vasculature). All the steps of the modelling procedure are explained in detail, special attention being paid to the meaning of all the different terms involved in the model. The chapter focuses on several mechanical aspects related to tumour growth, e.g., the activation of mechanotransduction pathways inside the cell, contact inhibition phenomena, the formation of stiffer fibrotic tissues, the adhesion phenomena characterizing the mechanical interaction between cells and between cell and extracellular matrix, and cell re-organization within the tissue.
Gregory J. del Zoppo and John M. Hallenbeck
- Published in print:
- 2002
- Published Online:
- March 2012
- ISBN:
- 9780198509806
- eISBN:
- 9780191724596
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198509806.003.0006
- Subject:
- Neuroscience, Disorders of the Nervous System
This chapter examines inflammatory events associated with focal cerebral ischaemia. It evaluates the hypothesis that polymorphonuclear (PMN) leukocytes participate in microvascular responses to ...
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This chapter examines inflammatory events associated with focal cerebral ischaemia. It evaluates the hypothesis that polymorphonuclear (PMN) leukocytes participate in microvascular responses to ischaemia and that they contribute directly to brain tissue injury and neuronal death. The chapter describes how PMN leucocytes can contribute to parenchymal injury and the steps involved in leucocyte invasion into the ischaemic central nervous system (CNS). It also discusses the genetic manipulation of leucocyte adhesion/activation and the role of leucocytes in cerebrovascular vasomotor reactivity.Less
This chapter examines inflammatory events associated with focal cerebral ischaemia. It evaluates the hypothesis that polymorphonuclear (PMN) leukocytes participate in microvascular responses to ischaemia and that they contribute directly to brain tissue injury and neuronal death. The chapter describes how PMN leucocytes can contribute to parenchymal injury and the steps involved in leucocyte invasion into the ischaemic central nervous system (CNS). It also discusses the genetic manipulation of leucocyte adhesion/activation and the role of leucocytes in cerebrovascular vasomotor reactivity.
C. Mathew Mate and Robert W. Carpick
- Published in print:
- 2019
- Published Online:
- October 2019
- ISBN:
- 9780199609802
- eISBN:
- 9780191747724
- Item type:
- book
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/oso/9780199609802.001.0001
- Subject:
- Physics, Condensed Matter Physics / Materials, Atomic, Laser, and Optical Physics
Friction, lubrication, adhesion, and wear are prevalent physical phenomena in everyday life and in many key technologies. The goal of this book is to incorporate a bottom up approach to friction, ...
More
Friction, lubrication, adhesion, and wear are prevalent physical phenomena in everyday life and in many key technologies. The goal of this book is to incorporate a bottom up approach to friction, lubrication, and wear into a versatile textbook on tribology. This is done by focusing on how these tribological phenomena occur on the small scale—the atomic to the micrometer scale—a field often called nanotribology. The book covers the microscopic origins of the common tribological concepts: roughness, elasticity, plasticity, friction coefficients, and wear coefficients. Some macroscale concepts (like elasticity) scale down well to the micro- and atomic scale, while other macroscale concepts (like hydrodynamic lubrication) do not. In addition, this book also has chapters on topics not typically found in tribology texts: surface energy, surface forces, lubrication in confined spaces, and the atomistic origins of friction and wear. These chapters covered tribological concepts that become increasingly important at the small scale: capillary condensation, disjoining pressure, contact electrification, molecular slippage at interfaces, atomic scale stick-slip, and bond breaking. Numerous examples are provided throughout the book on how a nanoscale understanding of tribological phenomena is essential to the proper engineering of important new technologies such as MEMS, disk drives, and nanoimprinting. For the second edition, all the chapters have been revised and updated, with many new sections added to incorporate the most recent advancements in nanoscale tribology. Another important enhancement to the second edition is the addition of problem sets at the end of each chapter.Less
Friction, lubrication, adhesion, and wear are prevalent physical phenomena in everyday life and in many key technologies. The goal of this book is to incorporate a bottom up approach to friction, lubrication, and wear into a versatile textbook on tribology. This is done by focusing on how these tribological phenomena occur on the small scale—the atomic to the micrometer scale—a field often called nanotribology. The book covers the microscopic origins of the common tribological concepts: roughness, elasticity, plasticity, friction coefficients, and wear coefficients. Some macroscale concepts (like elasticity) scale down well to the micro- and atomic scale, while other macroscale concepts (like hydrodynamic lubrication) do not. In addition, this book also has chapters on topics not typically found in tribology texts: surface energy, surface forces, lubrication in confined spaces, and the atomistic origins of friction and wear. These chapters covered tribological concepts that become increasingly important at the small scale: capillary condensation, disjoining pressure, contact electrification, molecular slippage at interfaces, atomic scale stick-slip, and bond breaking. Numerous examples are provided throughout the book on how a nanoscale understanding of tribological phenomena is essential to the proper engineering of important new technologies such as MEMS, disk drives, and nanoimprinting. For the second edition, all the chapters have been revised and updated, with many new sections added to incorporate the most recent advancements in nanoscale tribology. Another important enhancement to the second edition is the addition of problem sets at the end of each chapter.
C. Mathew Mate and Robert W. Carpick
- Published in print:
- 2019
- Published Online:
- October 2019
- ISBN:
- 9780199609802
- eISBN:
- 9780191747724
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/oso/9780199609802.003.0005
- Subject:
- Physics, Condensed Matter Physics / Materials, Atomic, Laser, and Optical Physics
The energies associated with surfaces—surface energy, interfacial energy, surface tension, and work of adhesion—drive many surface and interfacial phenomena including tribological ones such as ...
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The energies associated with surfaces—surface energy, interfacial energy, surface tension, and work of adhesion—drive many surface and interfacial phenomena including tribological ones such as adhesion and friction. This chapter discusses the physical origins of surface energies for liquids and solids, and how the concepts of capillary pressure, capillary condensation, wetting, and work of adhesion are derived from surface energy. Further, this chapter covers the different methods for measuring surface energies, including the most common method for solid surfaces: contact angle measurements of liquid droplets on surfaces. This chapter also introduces how surface energies and surface tensions lead to adhesion and adhesion hysteresis between contacting surfaces, which is followed up in the subsequent chapters on surface forces.Less
The energies associated with surfaces—surface energy, interfacial energy, surface tension, and work of adhesion—drive many surface and interfacial phenomena including tribological ones such as adhesion and friction. This chapter discusses the physical origins of surface energies for liquids and solids, and how the concepts of capillary pressure, capillary condensation, wetting, and work of adhesion are derived from surface energy. Further, this chapter covers the different methods for measuring surface energies, including the most common method for solid surfaces: contact angle measurements of liquid droplets on surfaces. This chapter also introduces how surface energies and surface tensions lead to adhesion and adhesion hysteresis between contacting surfaces, which is followed up in the subsequent chapters on surface forces.
Andrew Skotnicki
- Published in print:
- 2019
- Published Online:
- March 2019
- ISBN:
- 9780190880835
- eISBN:
- 9780190880866
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/oso/9780190880835.003.0004
- Subject:
- Religion, Theology, Religion and Society
The dynamics of conversion are presented in this chapter. It first clarifies what conversion is not. It is not adhesion—attaching oneself to a particular community and maintaining an oppositional or ...
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The dynamics of conversion are presented in this chapter. It first clarifies what conversion is not. It is not adhesion—attaching oneself to a particular community and maintaining an oppositional or at least suspicious attitude regarding other forms of association or structures of belief. Conversion is seen as the progressive expansion of one’s horizon of acceptance and care at the intellectual, moral, and spiritual levels. Its proof is precisely in its nonjudgmental and compassionate presence to new ideas and to the other. It always begins with a crisis in the lifeworld of the convert. This is followed by a gratuitous moment of acceptance despite one’s feeling of alienation. The “peak experience” then fosters an alteration of one’s personal narrative and community and an ongoing sense of accountability and embodiment of the communal narrative. The final stage of conversion reveals a profound sense of unity with all aspects of reality.Less
The dynamics of conversion are presented in this chapter. It first clarifies what conversion is not. It is not adhesion—attaching oneself to a particular community and maintaining an oppositional or at least suspicious attitude regarding other forms of association or structures of belief. Conversion is seen as the progressive expansion of one’s horizon of acceptance and care at the intellectual, moral, and spiritual levels. Its proof is precisely in its nonjudgmental and compassionate presence to new ideas and to the other. It always begins with a crisis in the lifeworld of the convert. This is followed by a gratuitous moment of acceptance despite one’s feeling of alienation. The “peak experience” then fosters an alteration of one’s personal narrative and community and an ongoing sense of accountability and embodiment of the communal narrative. The final stage of conversion reveals a profound sense of unity with all aspects of reality.
Nancy S. Kim
- Published in print:
- 2013
- Published Online:
- January 2014
- ISBN:
- 9780199336975
- eISBN:
- 9780199356003
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199336975.003.0003
- Subject:
- Law, Company and Commercial Law
This chapter examines the societal interests addressed by contracts and contract law. It discusses contract law and evolving business needs; contracts of adhesion; and function, fluidity, and ...
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This chapter examines the societal interests addressed by contracts and contract law. It discusses contract law and evolving business needs; contracts of adhesion; and function, fluidity, and instructive contracts.Less
This chapter examines the societal interests addressed by contracts and contract law. It discusses contract law and evolving business needs; contracts of adhesion; and function, fluidity, and instructive contracts.
