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Energy force and

Force and energy G GAmB(0 Free energy of interaction. Planar systems between half-spaces A and B across medium m of variable thickness Z. [Pg.102]

GAm/Bm(7) Planar systems in outside/in sequence of materials to emphasize the interaction between the Am and Bm interfaces. [Pg.102]

GAmBiB, bi) Used when there is a single layer of material Bi constant thickness bi on half-space B or, more generally, with many layers on both A and B, use G(l ai, a-2, bi, b2.) to show variable spacing Z (italic) with other distances constant (nonitalic). [Pg.102]


As noted above, one of the goals of NAMD 2 is to take advantage of clusters of symmetric multiprocessor workstations and other non-uniform memory access platforms. This can be achieved in the current design by allowing multiple compute objects to run concurrently on different processors via kernel-level threads. Because compute objects interact in a controlled manner with patches, access controls need only be applied to a small number of structures such as force and energy accumulators. A shared memory environment will therefore contribute almost no parallel overhead and generate communication equal to that of a single-processor node. [Pg.480]

Differentiating Eq. 4.21 with respect to crack length c, we obtain the critical forces and energy as... [Pg.375]

Liquids in motion have characteristics different from liquids at rest. Frictional resistances within the fluid, viscosity, and inertia contribute to these differences. Inertia, which means the resistance a mass offers to being set in motion, will be discussed later in this section. Other relationships of liquids in motion you must be familiar with. Among these are volume and velocity of flow flow rate, and speed laminar and turbulent flow and more importantly, the force and energy changes which occur in flow. [Pg.589]

What Do We Need to Know Already We need to be familiar with SI units (Appendix IB) and the concepts of force and energy (Section A). This chapter also develops the techniques of reaction stoichiometry (Sections L and M) by extending them to gases. [Pg.261]

In the first chapter several traditional types of physical models were discussed. These models rely on the physical concepts of energies and forces to guide the actions of molecules or other species, and are customarily expressed mathematically in terms of coupled sets of ordinary or partial differential equations. Most traditional models are deterministic in nature— that is, the results of simulations based on these models are completely determined by the force fields employed and the initial conditions of the simulations. In this chapter a very different approach is introduced, one in which the behaviors of the species under investigation are governed not by forces and energies, but by rules. The rules, as we shall see, can be either deterministic or probabilistic, the latter leading to important new insights and possibilities. This new approach relies on the use of cellular automata. [Pg.9]

The fiuid-phase simulation approach with the longest tradition is the simulation of large numbers of the molecules in boxes with artificial periodic boundary conditions. Since quantum chemical calculations typically are unable to treat systems of the required size, the interactions of the molecules have to be represented by classical force fields as a prerequisite for such simulations. Such force fields have analytical expressions for all forces and energies, which depend on the distances, partial charges and types of atoms. Due to the overwhelming importance of the solvent water, an enormous amount of research effort has been spent in the development of good force field representations for water. Many of these water representations have additional interaction sites on the bonds, because the representation by atom-centered charges turned out to be insufficient. Unfortunately it is impossible to spend comparable parameterization work for every other solvent and... [Pg.296]

M. Ishikawa, S. Okita, N. Minami, and K. Miura, Load Dependence of Lateral Force and Energy Dissipation at NaF(001) Surface , Surf. Sci., 445,488 (2000). [Pg.201]

The equivalence of the force and energy description of surface tension and surface energy... [Pg.13]

The bioadhesive characteristics of tablets for oral use made from modified starch, poly(acrylic acid), polyethylene glycol) and sodium carboxymethyl cellulose were recently investigated [406]. In this work, the force and energy adhesion were determined in vitro, and maximum adhesion times were evaluated in vivo in humans [406], In the in vitro, studies, the poly(acrylic add) gave the best performance, however in vivo bioadhesion was not strongly correletated with... [Pg.34]

We will see later on that we can use this expression to convert between force and energy for specific types of atoms and molecules (specific values of n and m). For now, this expression helps us find the equilibrium bond distance, ro, which occurs when forces are equal (the sum of attractive and repulsive forces is zero) or at minimum potential energy (take the derivative and set it equal to zero) ... [Pg.14]

Both the fluid mechanics and the statistical mechanics on which some of the key theoretical results of the chapter are based are sufficiently complicated that we only sketch the highlights of these topics. We attempt to impart some physical plausibility to these theories, however, by using both force and energy perspectives in discussing the viscous resistance to flow. [Pg.147]

The process of igniting the flame is called combustion. Combustion is a type of chemical reaction that rearranges the elements in fuel to form new molecules. It is fundamentally different than a phase change, which usually just changes the forces and energy between molecules in a substance rather than making new substances. [Pg.82]

Perhaps the most remarkable feature of modem chemical theory is the seamless transition it makes from a microscopic level (dealing directly with the properties of atoms) to describe the structure, reactivity and energetics of molecules as complicated as proteins and enzymes. The foundations of this theoretical structure are based on physics and mathematics at a somewhat higher level than is normally found in high school. In particular, calculus provides an indispensable tool for understanding how particles move and interact, except in somewhat artificial limits (such as perfectly constant velocity or acceleration). It also provides a direct connection between some observable quantities, such as force and energy. [Pg.19]

Chapter 3 is the physics chapter. The first edition jumped into Newton s laws written with calculus (F = dp/dt), which many students found overwhelming. This version moderates that introduction by presenting the concepts of force and energy more gradually. New to this edition is an extensive discussion of atoms and molecules as charged objects with forces and potential energy (this discussion was previously much later in the book). [Pg.225]

The possible presence of polarization of ut type (P a) induced in the non-uniform field rather close to an ion, but still within the validity of the assumptions ofEq.s (48)-(51), (57), and (58) is a possible source of error. Physically, ut polarization consists of dipole translation along field towards the ion, increasing the local value of AA) cos 1L(x)A, and Pui,a- To examine this requires knowledge of the binding forces and energies between water molecules. The potential energy Mie function... [Pg.221]

The theoretical treatment of liquid-phase reaction kinetics is limited by the fact that no single universal theory on the liquid state exists at present. Problems which have yet to be sufiiciently explained are the precise character of interaction forces and energy transfer between reacting molecules, the changes in reactivity as a result of these interactions, and finally the role of the actual solvent structure. Despite some hmitations, the absolute reaction rates theory is at present the only sufficiently developed theory for processing the kinetic patterns of chemical reactions in solution [2-5, 7, 8, 11, 24, 463-466]. According to this theory, the relative stabilization by solvation of the initial reactants and the activated complex must be considered cf. Section 5.1). [Pg.218]

In this chapter, we give approximate analytic expressions for the force and potential energy of the electrical double-layer interaction two soft particles. As shown in Fig. 15.1, a spherical soft particle becomes a hard sphere without surface structures, while a soft particle tends to a spherical polyelectrolyte when the particle core is absent. Expressions for the interaction force and energy between two soft particles thus cover various limiting cases that include hard particle/hard particle interaction, soft particle/hard particle interaction, soft particle/porous particle interaction, and porous particle/porous particle interaction. [Pg.357]

One common feature of aii moduii is that any strain generated in a soiid is iineariy proportional to the stress. This obviousiy requires that whatever stress is appiied shouid not break or permanentiy bend the sampie and that no significant energy be dissipated when the sample is strained. To revert to a carefui dynamic description of the dispiacements, forces and energy is mandatory for high dissipation materiais. [Pg.354]

The simulation details such as force and energy calculation including the potential models of H2O and HsO are similar to the teehniques and methods described in the earher discussion. Unlike other simulations" " of an exeess proton in bulk water we... [Pg.183]


See other pages where Energy force and is mentioned: [Pg.1695]    [Pg.63]    [Pg.147]    [Pg.340]    [Pg.469]    [Pg.1901]    [Pg.871]    [Pg.774]    [Pg.194]    [Pg.175]    [Pg.55]    [Pg.13]    [Pg.124]    [Pg.8]    [Pg.158]    [Pg.186]    [Pg.4]    [Pg.2384]    [Pg.99]    [Pg.289]    [Pg.264]    [Pg.1660]    [Pg.186]    [Pg.265]    [Pg.6]    [Pg.16]   
See also in sourсe #XX -- [ Pg.15 , Pg.29 , Pg.30 , Pg.31 , Pg.32 ]




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Energies and Forces of Interaction

Energy Minima, Force Constants and Structure Correlation

Estimation of Crack-Driving Force G from Energy Loss Rate (Irwin and Kies

Force and potential energy

Force-field Energies and Thermodynamics

Force-field methods, calculation of molecular structure and energy

Forces and Potential Energy in Atoms

Forces and Potential Energy in Molecules Formation of Chemical Bonds

Forces, Energy, and Work

Interaction Energies (Forces) Between Emulsion Droplets and their Combinations

Interaction Energies and Forces

Interaction Forces (Energies) Between Particles or Droplets Containing Adsorbed Non-ionic Surfactants and Polymers

Intermolecular forces and potential energy

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Potential Energy Surfaces and Intermolecular Forces

Potential of Average Force and Helmholtz Energy Changes

The Classical Approach Vibrational and Nonbonded (Force Field) Energies

Total energy, forces, and stresses

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